FUNDAMENTALS OF POWER PLANT ENGINEERING THERMODYNAMICS
1.
An air bubbl bubblee rises from from the bottom bottom of a well well where where the temper temperature ature is is 25 ºC, to to the surface surface where where the temperature is 27 ºC. Find the percent increase in the volume of the bubble if the depth of the well is 5 m. Atmospheric pressure is 101,52 !ascals. Answer: A A. "#.$ %. 5&.7 C. "1.$ '. $.&
2.
An idea ideall (as is "5 psi( psi( and 0 ºF is heat heated ed in a clos closed ed conta contain iner er to 1$0 ºF. ºF. )hat )hat is the the final final pressure* Answer: B A. 5" psia %. &5 psia C. 75 psia '. "$ psia
$.
A lar( lar(ee minin( minin( comp compan+ an+ was was prov provide idedd with with a $000 $000 cm $ of compressed air tan. Air pressure in the tan drops from 700 !a to 10 !a while the temperature remains unchan(ed at 2 ºC. )hat percenta(e has the mass of air air in the tan been reduced* Answer: A A. 7" %. 72 C. 7& '. 7
".
-ow much much wor wor is is necessar necessar++ to compress compress air air in an insulat insulated ed c+lind c+linder er from from 0.20 m $ to 0.01 m $. se /1 20 ºC and ! 2 100 !a. Answer: D A. 11$." %. 121." C. 110.1 '. 115.7
5.
A heat heat en(ine en(ine is operat operated ed between between temper temperatu ature re limits limits of 1$70 ºC and 2&0 ºC. ºC. n(ine n(ine is supplie suppliedd with 1",1"23wh. Find the Carnot c+cle efficienc+ in percent. Answer: C A. 70.10 %. &5.05 C. &7.5& '. &#.$2
&.
A clos closed ed vesse vessell contai contains ns air air at a pres pressu sure re of 1&0 1&0 43m 43m2 (au(e and temperature of $0 ºC. /he air is heated at constant volume to &0 ºC with the atmospheric pressure of 75# mm -(. )hat is the final (au(e pressure* Answer: B A. 17" %. 1& C. 1&7 '. 172
7.
)hat )hat is the tempe temperat rature ure in ºC of of 2 liters liters of water water at $0 ºC after after 500 Calor Calories ies of of heat have have been been added* Answer: B A. $5.70 %. $0.2 C. $ '. $#.75
.
A volume of "5 "50 cm$ of air is measured at a pressure of 7"0 mm -( absolute and a temperature of 20 ºC. )hat is the volume in cm $ at 7&0 mm -( absolute and 0 ºC* Answer: B A. 51&.12 %. "0.25 C. &20.7& '. $75.5
#.
Assumin( Assumin( compres compression sion is is accordin( accordin( to to the law !cons !constant tant.. Calculate Calculate the initia initiall volume volume of (as at $ a pressure of 2 bar which will occup+ a volume of & m when it is compressed to a pressure of "2 bar. Answer: A A. 12&$ %. 120$ C. 1$0$ '. 1$&$
10. A steam steam condense condenserr receiv receives es 10 ( per second second of steam with an enthalp+ enthalp+ of 2,5703 2,5703(. (. 6team 6team condenses into liuid and leaves with an enthalp+ of 1&03(. Coolin( water passes throu(h the condenser with temperature increases from 1$ ºC to 2" ºC. Calculate the coolin( water flowrate in (3s. A. 5$$ %. 51 C. 52$ '. 52 11. 11. A steam steam e8pands e8pands adiabatica adiabaticall+ ll+ in a turbine turbine from 2,000 !a, !a, "00 ºC to "00 !a, 250 ºC. )hat is the effectiveness o( the process in percent assumin( an atmospheric temperature of 15 ºC. 4e(lect chan(es in inetic and potential ener(+. Answer: C A. 2 %. " C. 0 '. & 12. 6team enters enters the superh superheaters eaters of of a boiler at a pressure pressure of 25 bar and and dr+ness dr+ness of 0.# and leaves leaves at the same pressure at a temperature of $70 ºC. Calculate the heat ener(+ supplied in the suerheaters. !roperties of steam9 At 25 bar and $70 ºC :h $171.3(; and at 25 bar and 0.# dr+ness :h f #&2.113(, #&2.113(, h f( 1"1.013(;. Answer: Answer: C A. "07."& %. "0.57 C. "05.51 '. "0&.5"
1$. /he thermal efficienc+ efficienc+ of a particular en(ine operatin( on an ideal c+cle is $5<. Calculate Calculate the heat supplied per 1200 watt=hr of wor developed in . Answer: A A. 12,$"$ %. 10,21& C. 1",21 '. 11,10 1". 'eterm 'etermine ine the the avera(e avera(e Cp value in 3( 3(=> => of a (as if 522 of heat is necessar necessar++ to raise raise the temperature from $00 > to 00 > main( the pressure constant. Answer: B A. 1.""0 %. 1.0"" C. 1.0$ '. 1.02& 15. 'eterm 'etermine ine the force force in 4ewtons 4ewtons reuire reuiredd to produc producee an accelera acceleratio tionn of 0.$0 m3s 2 on a 0.05 ( mass. Answer: C A. 0.01 4 %. 0.025 4 C. 0.015 4 '. 0.200 4 1&. Ammon Ammonia ia wei(hin( wei(hin( 22 ( is confine confinedd inside inside a c+lin c+linder der euipp euipped ed with a piston piston has an initia initiall pressure of "1$ !a at $ ºC. ?f 2#00 of heat is added to the ammonia until its pressure and temperature are "1$ !a and 100 ºC, respectivel+. )hat is the amount of wor done b+ the fluid in * Answer: A A. &&7 %. $0" C. "20 '. 502 17. )hat is the total total reuired reuired heatin( heatin( ener(+ ener(+ in raisin( raisin( the temperatur temperaturee of a (iven (iven amount of water water when the ener(+ supplied is 1000 wh with heat losses of 25<* Answer: C A. 1000 %. 1500 C. 1$$$ '. 1250 1. A ves vesssel of of 0.05 0.05 m $ capacit+ is well insulated and is divided euall+ b+ ri(id conductin( diaphra(m. ?nitiall+ both halves contain air at pressure of 1$7. !a and "1$." !a and a temperature of 27 ºC and 177 ºC respectivel+. )hat is the increase of entrop+ of the s+stem in 3 ºC. Answer: C A. 1.002 %. 0.500 C. 0.0017$ '. 0.100
1#. A certai certainn (as at 101.$25 101.$25 !a !a and 1& ºC whose whose volume volume is 2.$ m $ are compressed into a stora(e vessel of 0.$1 m $ capacit+. %efore admission, the stora(e vessel contained the (as at a pressure and temperature of 1$7. !a and 2" ºC. after admission, the pressure has increased to 1171. !a. )hat should be final temperature of the (as in the vessel in >elvin* Answer: B A. 2#.0 %. $1#.0 C. 10 '. "20 20. 6team 6team enters enters a throt throttli tlin( n( calorime calorimeter ter at a pressu pressure re of 1.0$ 1.0$ @pa. @pa. /he calorim calorimete eterr downst downstrea ream m pressure and temperature are respectivel+ 0.100 @pa and 125 ºC. what is the percenta(e moisture of the suppl+ steam* !roperties of steam9 ! 1.0$ @pa h( 227#.253( h f( 2010.7 3( At 0.100 @pa and 125 ºC9 h 272&.&3(. Answer: A A. 2.2& %. 5.21 C. $.15 '. 1.# 21. )hat pressu pressure re is column column of of water 100 100 cm hi(h hi(h euivalent euivalent to* to* Answer: B 2 A. #07 #07 d+ne d+nes3 s3cm cm %. #07 43m2 C. 0.10 bar '. #100 100 43m2 22. A water temperature rise of 1 1 ºF in the water cooled cooled condenser condenser is euivalent euivalent in ºC to9 Answer: C A. =#."" ºC ºC %. 2&$.5& .5& ºC C. 10 ºC '. 7.7 ºC ºC 2$. 6team 6team flows flows into a turbi turbine ne at the rate of 10 (3s and 10 ) of heat are lost from from the turbine. turbine. ?(norin( elevation and inetic ener(+ effects, calculate the power output from the turbine. 4ote9 h1 27$#.0 3( and h 2 2$00.5 3(. Answer: C A. "&05 ) %. "#7$ ) C. "$75 ) '. "000 ) 2". /he enthalp+ enthalp+ of air is increase increasedd b+ 1$#.5& 1$#.5& 3( in a compresso compressorr. /he rate of air flow flow is 1&."2 (3min. the power input is ".2 ). ). )hich of the followin( values most nearl+ euals the heat loss from the compressor in )* Answer: A A. =10 %. 10.2 C. =###.#5 '. #.#5
25. A Carnot Carnot en(ine en(ine reuires reuires $5 3s from from the hot source. source. /he en(ine en(ine produces produces 15 ) of of power and temperature of the sin is 2&ºC.)hat is the temperature of the hot source in ºC* Answer: C A. 2"5.57 %. 210.10 C. 250.1 '. 2&0.& 2&. /he ma8imum thermal efficienc+ efficienc+ possible possible for a power c+cle operatin( between between 1200 ºF and 225 ºF is9 Answer: B A. 5< %. .7$< C. 57.5"< '. 57."0< 27. A Carnot Carnot en(ine en(ine receives receives 1$0 %tu of heat from a hot reservoir reservoir at 700 ºF and reects reects "# %tu of heat. heat. Calculate the temperature of the cold reservoir. Answer: D A. =21.# ºF ºF %. =2".2 ºF C. =20. ºF '. =22.7 ºF ºF 2. 2. A tan tan con conta tain inss 0 ft $ of air at a pressure of $50 psi. if the air is cooled until its pressure and temperature decrease to 200 psi and 70 ºF respectivel+, what is the decrease in internal ener(+* Answer: B
A. %. C. '.
"575 =5507 5552 0
2#. ?f 10 lbs of water water evaporated evaporated at atmosp atmospheric heric pressur pressuree until a volume volume of 2.5 2.5 ft $ is occupied, how much wor is done* Answer: A A. &10, &10,$5 $5 ft= ft=lb lb %. 0 C. =&10 =&10,5 ,5$ $ ft=l ft=lbb '. 550, 550,00 0000 ft= ft=lb lb $0. A reverse reverse Carnot Carnot c+cle reuires reuires $ -p and e8tracts e8tracts ener(+ ener(+ from a lae to heat a house. house. ?f the house is ept at 70 ºF and reuires 2000 %tu per minute, what is the temperature of the lae* Answer: B A. $5 ºF %. $& ºF C. $# ºF '. "0 ºF $1. A pressure pressure (a(e re(iste re(isters rs 50 psi( in a re(ion where the baromete barometerr is 1".25 psia. Find the absolut absolutee pressure in psia. Answer: A A. &".25 %. ""$ C. 151.$25 '. $5.75
$2. A pump pump dischar( dischar(es es 50 tons of water water per hour hour to a hei(ht hei(ht of m, the overall overall effic efficien ienc+ c+ of the pumpin( s+stem bein( &#<. Calculate the output output and input power. power. Answer: A A. 1.0# 1.0# ) B 1.5 1.5 ) ) %. 2.0# 2.0# ) B 2.5 2.5 ) ) C. 1.0# 1.0# ) B 2.5 2.5 ) ) '. 2.0# 2.0# ) B 1.5 1.5 ) ) $$. A condens condenser er vacuum vacuum (au(e reads reads 715 mm -( when the baromet barometer er stands stands at 757 mm -(. )hat is the absolute pressure in the condenser in !a. Answer: C A. 1#&.2 #&.255 !a %. 100.#2 .#2 ! !a C. 5.&0 !a '. #5.$$ ! !a $". il flows flows full bore at a velocit+ velocit+ of 2 m3s throu(h throu(h a nest of 1& tubes in a sin(le sin(le pass cooler cooler.. /he internal diameter of the tubes is $0 mm and the densit+ of the oil is 0.5 (3li. Find the volume flow in liters per second. Answer: D A. 20 %. 21 C. 22 '. 2$ $5. Calculate Calculate the uantit+ uantit+ of heat to be transferre transferredd to 2.25 ( of brass to raise its temperatu temperature re from 20 ºC to 2"0 ºC tain( the specific heat of the brass as 0.$#" 3(=>. Answer: C A. 51#.0$ .0$ %. 15#.0$ .0$ C. 1#5.0$ .0$ '. 5#1.0$ .0$ $&. /hree /hree cubic cubic meter meter of air at a pressu pressure re of 20 !a( is compres compressed sed at constan constantt temperat temperature ure to a pressure as "25 !a(. Calculate Calculate the final volume of the the air. A. 0.0 m$ %. 0.&# m$ C. 0.#2 m=$ '. 0.#& m$ $7. /he pressure pressure of the air air in a startin( startin( air vessel vessel is "0 bar and the the temperatur temperaturee is 2" ºC. ?f a fire in the vicinit+ causes the temperature to rise to &5 ºC, find the pressure of the air. 4e(lect an+ increase in volume of the vessel. Answer: A A. "5.52 ba bar %. 5".52 bar C. "2.55 bar '. "".55 ba bar $. ne cubic cubic meter meter of a perfect perfect (as at a consta constant nt pressur pressuree of 1 bar and temperat temperature ure of 17 ºC are $ compressed to a volume of 0.50 m and the final pressure is & bar. Calculate the final temperature. Answer: C
A. %. C. '.
70 ºC 5&0 ºC 5#7 ºC &0 ºC
$#. An air air compre compress ssor or deliv delivers ers 0.20 0.20 m$ of air at a pressure of 50 !a and $1 ºC into an air reservoir. /ain( the (as constant of air as 0.27 3(=>, calculate the mass of air delivered. Answer: B A. 1.5# ( %. 1.#5 ( C. 5.#1 ( '. 5.1# ( "0. An o8+(e o8+(enn c+lind c+linder er of volum volumee 2.$ ft$ has a pressure of 2200 psi( and is at 70 ºF. determine the mass of o8+(en in the c+linder. Answer: C A. 2&.&& lb lbs %. 2&.& lbs C. 2.&& lbs '. 2. lb lbs "1. )hat )hat is the power power of a steam steam et 15 mm in diamet diameter er movin( movin( at 750 m3s* 6team 6team condi conditio tion, n, 1." 2 $ (3cm , dr+ and saturated : v 1.25& m 3(;. Answer: A A. 2#.&7 ) ) %. $#.&7 ) C. 1#.&7 ) '. "#.&7 ) ) "2. -ow much power power is there in the inetic ener(+ of the atmosphere atmosphere :densit+ 1.217 (3m $; at 5& ph wind velocit+* Consider the section that passes throu(h a $ m diameter circular area normal to the velocit+. Answer: C A. 10.21 ) ) %. 15.21 ) C. 1&.21 ) '. 17.21 ) ) "$. An electric electric heater heater is to heat 11 ( of oil per min. min. from ".5 ºC to &5.5 ºC. 6pecific 6pecific heat heat of the oil is 2.1 3(m= ºC. -ow man+ watts should this heater consume* Answer: D A. 20,"" ) %. $$,"" ) C. 20,"00 ) '. 2$,""2 ) "". Find the the enthalp+ enthalp+ of 1 ( of wet saturated saturated steam steam at a pressure pressure of 0.20 bar and dr+nes dr+nesss fraction fraction of 0.5. At 0.20 bar, h f 251 3( B h f( 2$5 3(. Answer: C A. 2200 200 3( 3( %. 2525 2525.$ .$00 3 3(( C. 2255 2255.$ .$00 3 3(( '. 2000 000 3( 3( "5. ?f the specific specific enthalp+ of wet saturated steam at a pressure pressure of 11 11 bar is 2&1 2&1 3(, find its dr+ness dr+ness fraction. At 11 bar, h f 71 3( B hf( 2000 3(. Answer:C A. 0.75 %. 0.5 C. 0.#5 '. 0.&5
"&. Find the the heat transfer transfer reuired reuired to conver convertt 5 ( of water at a pressure pressure of 20 bar and and temperature temperature of 21 ºC into steam of dr+ness fraction 0.#0 at the same pressure. !roper !ropertie tiess of stea steam9 m9 ! 20 barD barD hf #0# #0# 3 3( (DD hf( 1#0 3( 4ote9 for water at 21 ºC, h 3(. 3(. Answer: C A. 10,&10 %. 11,&1 ,&10 C. 12,&10 '. 15,&10 "7. A closed closed vessel vessel contai containn air at a pressu pressure re of 1"0 >pa( >pa( and temper temperatu ature re of 20 ºC. Find the final final (au(e pressure if the air is heated at constant volume to "0 ºC. /ae the atmospheric pressure as 75# mm -(. A. 15&."& %. 1"&."& C. 1$&."& '. 12&."& ". )ater substanc substancee at 70 bar and &5 ºC enters enters a boiler tube of constant constant inside inside diameter diameter of 25 mm. /he water leaves the boiler tube at 50 bar and 700 > at velocit+ of 100 m3s. Calculate the inlet volume flow in li.3sec. At 70 bar B &5 ºC, v1 0.001017 m$3( , at 50 bar B 700 >, v2 0.0&01 m$3(. Answer: C
A. %. C. '.
0.75 0.&" 0.2 0.#&
"#. A (roup (roup of 50 persons persons attend attend a secret secret meetin( meetin( in room room which is 12 m wide wide b+ 10 m lon(, and a ceilin( hei(ht of $ m. /he room is completel+ sealed off and insulated. ach person (ives off 150 Cal per hour of heat and occupies a volume of 0.20 m $. /he room has an initial pressure of 101.$ !a and temperature of 1& ºC. Calculate the room temperature after 10 minutes. se E 0.27 3(=> and C v 0.171 Cal3(=>. Answer:A A. $$.1 ºC ºC %. $7.7 ºC C. $.7 ºC '. $1.7 ºC ºC 50. 50. 6tea 6team m at 1000 1000 lbf 3 ft2 pressure and $00 ºE has specific volume of &.5 ft $3lbm and a specific enthalp+ of #00 ft=lb f 3lb 3lbm. . Find the internal ener(+ per pound mass of steam. Answer: B A. 2500 500 ft=l ft=lbbf 3lb 3lbm %. $$00 ft ft=lbf 3lb 3lbm C. 5"00 ft ft=lbf 3lb 3lbm '. � #00 ft=l ft=lbbf 3lb 3lbm 51. 'etermine 'etermine the avera(e avera(e constant constant pressure pressure specific specific heat heat of steam at 10 !a and "5. ºC. 4ote9 From steam table, at "7..7 ºC, h 251.1 3(. Answer: A A. 1.7# 1.7# 3 3(º (ºC C %. 10.2 10.2 3 3(º (ºC C C. $0.5 $0.577 3 3(º (ºC C '. 100. 100.11 3 3( (ºC ºC
52. A 10 m$ vessel initiall+ contains 5 m $ of saturated vapor at 100 !a. Calculate the internal ener(+ of the s+stem. !roperties of liuid water and saturated vapor9 At 100 !a, v f 0.0010"$ m $3(D v( 1.&#"0 m$3(D uf "17.$ 3(D u ( 250&.1 3(. Answer: A A. 2.0 8 10& %. 1.0 810& C. $.0 8 10& '. 5.0 8 10& 5$. 5$. A ves vesse sell with with a volu volume me of 1 m $ contains liuid water and water vapor in euilibrium at &00 !a. /he liuid water has a mass of 1 (. Calculate the mass of the water vapor. !roperties of liuid water and water vapor at &00 !a9 v f 0.001101 m $3( v( 0.$157 m$3(. Answer: D
A. %. C. '.
1.57 ( 1.# ( 2.5" ( $.1& (
5". ?f & liters of of a (as at a pressure pressure of 100 !aa are compres compressed sed reversib reversibl+ l+ accordin( accordin( to to ! 2 C, until the volume becomes 2 liters. Find the final pressure. Answer: C A. &00 !aa %. 00 !aa C. #00 !aa '. 1000 ! !aa 55. /he flow ener(+ ener(+ of 12" 12" liters per per minute minute of a fluid passin( passin( a boundar+ boundar+ to s+stem s+stem is 10.5 3min. 3min. 'etermine the pressure at this point. Answer: A A. 75 !a %. &75 !a C. #75 !a '. 575 !a 5&. )or done b+ a substance in reversible non=flow manner manner in accordance accordance with 1003p ft $, where ! is in psia. valuate the wor done on or b+ the substance as the pressure increases from 10 psia to 100 psia. Answer: B A. $$,1 $$,157 57.2 .222 ft=l ft=lbb %. =$$, =$$,15 157. 7.22 22 ft=l ft=lbb C. "$,1 "$,157 57.2 .222 ft=l ft=lbb '. ="$, ="$,15 157. 7.22 22 ft=l ft=lbb 57. A closed closed (aseous (aseous s+stem s+stem under under(oe (oess a revers reversibl iblee proces processs durin( durin( which which 25 %tu are reected reected,, the $ $ volume chan(in( from 5ft to 2 ft , and the pressure remains constant at 50 psia. Find the chan(e of internal ener(+. Answer: C A. =52 =52.7& .7& %tu %tu %. =2.7& %tu C. 2.7& %tu '. 52.7& %t %tu
5. Assume Assume lb of a substance substance receive receive 2"0 %tu of heat at constant constant volume volume and under(o under(o a temperature temperature chan(e of 150 ºF. 'etermine the avera(e specific heat of the substance durin( the process. Answer: D
A. %. C. '.
0.5 0.5 %tu3 %tu3lb lb ºF 0.$ %tu %tu3lb ºF 0."0 0."0 %tu3 %tu3lb lb ºF 0.20 0.20 %tu3 %tu3lb lb ºF
5#. /he followin( followin( e8press e8pressions ions relate relate to a particular particular (aseous (aseous mass9 ! #5/, #5/, h 120 0.&0/ 0.&0/ where $ these units obtain in psf, in ft 3lb, / in ºE and h in %tu3lb. ?f the specific heats are temperature dependent onl+, find C p and Cv. Answer: Answer: A A. 0.& %tu3lb %tu3lb ºE, 0." 0." %tu3 %tu3lb lb ºE %. 0.5 %tu3lb %tu3lb ºE, 0.50 0.50 %tu3lb %tu3lb ºE C. 0.&0 0.&0 %tu3l %tu3lbb ºE, ºE, 0.7 0.7 %tu3l %tu3lbb ºE '. 0.50 0.50 %tu3l %tu3lbb ºE, 0." 0." %tu3l %tu3lbb ºE &0. Calculate Calculate the entrop+ entrop+ of steam steam at &0 psia with with a ualit+ of 0.&0. 0.&0. properties properties of steam steam at &0 psia9 6 f 0."27" %tu3lb ºE. Answer: B A. 0."2 0."2"7 "7 %tu3 %tu3lb lb ºE %. 1.15 1.1577 77 %tu3 %tu3lb lb ºE ºE C. 0.7$ 0.7$0$ 0$ %tu3 %tu3lb lb ºE ºE '. 0.# 0.#&& %tu %tu3l 3lbb ºE &1. Find the chan(e chan(e in in interna internall ener(+ ener(+ of of 5 lbm of o8+(en when the temperature chan(es from 100 ºC to 120 ºC, Cv 0.157 %tu3lb m= ºE. Answer: B A. 1".70 %t %tu %. 15.70 %tu C. 1&.0 %tu '. 1"7 %tu &2. &2. )ater ater :6pec :6pecif ific ic heat heat,, C v ".23(=>; is bein( heated b+ 1500= ) heater. )hat is the rate of chan(e in temperature of 1 ( of water* Answer: C A. 0.0" 0.0"$$ >elv >elvin in3s 3s %. 0.17 0.17## >el >elvi vinn3s C. 0.$5 0.$577 >el >elvi vinn3s '. 1.50 1.50 >elv >elvin in3s 3s &$. &$. ne ne ilo ilo(r (ram am of of water water :Cv ".2 3(=>; is heated b+ $00 %tu of ener(+. )hat is the chan(e in temperature in >* Answer: A A. 75.$& > %. 125.20 > C. 7$.0 > '. 17.#& > &". 'etermine 'etermine the chan(e chan(e in enthalp+ enthalp+ per lb mass of nitro(e nitro(enn (as as its temperature temperature chan(es chan(es from from 500 ºF to 200 ºF. :C p 0.2"$ %/3lb m ºE;. Answer: A A. =7". =7"."# "# %tu3 %tu3lb lbm %. =72. =72.& & %tu3 %tu3lb lbm C. =&. =&."7 "7 %tu3 %tu3lb lbm '. =&$. =&$.7 7 %tu3 %tu3lb lbm
&5. Calculate Calculate the chan(e chan(e in enthalp+ enthalp+ as 1 ( of nitro(en nitro(en is heated from from 1000 > to 1500 >, assumin( assumin( the nitro(en is an ideal (as at a constant pressure. /he temperature dependent specific heat of nitro(en is C p $#.0& G 512.7# / =1.5 1072.7 / =2 G 20." / =$ where C p is in 3(=mol, and / is in >. Answer: B A. &00 %. .27 .27 C. 00 '. #7.27 .27 &&. )hat is the the resultin( resultin( pressure pressure when when one pound pound of air at 15 psia and 200 200 ºF is heated at constan constantt volume to 00 ºF* A. 15 psia %. 2.& psia C. $&." psia '. 52.1 ps psia &7. /he temperatu temperature re of an ideal ideal (as remains constant constant while while the absolute absolute pressure pressure chan(es chan(es from 10$." !aa to 27.2 !aa. ?f the initial volume is 0 liters, what is the final volume* Answer: B A. 5 li %. 10 li C. 15 li '. 20 li &. For a certain certain ideal ideal (as, E 0.277 0.277 3(=> 3(=> and 1.$". 1.$". )hat )hat are the values values of C p and Cv* Answer: A
A. %. C. '.
0.##" 0.##" 3 3(=> (=>,, 0.721$ 0.721$ 3( 3(=> => 1 3 3(=> (=>,, 0.12 0.12"" 3 3(= (=> > 0.712" 0.712" 3 3(=> (=>,, 0.12" 0.12" 3( 3(=> => 0.##" 0.##" 3 3(=> (=>,, 0.&12" 0.&12" 3( 3(=> =>
&#. A mi8ture mi8ture is formed formed at &#." !aa, !aa, $7. ºC b+ brin(in( brin(in( to(ether to(ether these (ases (ases each volume volume before before mi8in( measured at &#." !aa, $7. ºCD $ mol C 2, 2 mol 42, ".5 mol 2. Find the partial pressure of C2 after mi8in(. Answer: A A. 217.7 17.7$$ !a !aaa %. 1"5.1 "5.155 !aa !aa C. $2&.& 2&.&00 !aa !aa '. ""5.1 "5.155 !a !aaa 70. An air with with mass mass of 0."5" 0."5" ( and an unnown unnown mass mass of C 2 occup+ an 5 liters tan at 20& >paa. ?f the partial pressure of the C 2 is $"".7" !aa, determine its mass. Answer: A A. 0.1$ ( ( %. 0.2$ ( C. 0.1$ ( '. 0.2$ ( ( 71. After series series of state state chan(es, chan(es, the pressure pressure and volume volume of 2.2& ( of 4itro(en 4itro(en are each doubled doubled.. )hat is H6* Answer: A A. 2.0 2.077 3 3( (=> => %. 2.2& 2.2& 3 3(= (=> > C. 2.# 2.#77 3 3(= (=> > '. $."0 $."077 3 3( (= =
72. /he tempe temperat rature ure of ".2 ".2 lb of 8+(en 8+(en occup occup+in +in(( ft $ is chan(ed from 110 ºF to 200 ºF while pressure remains constant constant at 115 115 psia. 'etermine the final volume. volume. Answer: C $ A. 7.2& ftft %. .2& ft$ C. #.2& ft$ '. 10.2& ftft$ 7$. /went+ went+ (rams (rams of of o8+(en o8+(en (as : : 2; are compressed at a constant temperature of $0 ºC to 5< of their ori(inal volume. )hat wor is done on the s+stem* se E of air, 0.0&1# Cal3(m=> . Answer: Answer: D A. 2" Cal %. #2" Cal C. #"" Cal '. 112" Cal 7". 7". -eli -elium um :E 0."# 0."#& & %tu3 %tu3lb lbm ºE; is compressed isothermall+ from 1".7 psia and & ºF. /he compression ratio is ". Calculate the wor done b+ the (as. Answer: A A. =$&" =$&" %tu %tu3lb 3lbm %. =1"5 =1"5 %tu %tu3lb 3lbm C. =17 =17 %tu %tu3lb 3lbm '. ="&. ="&.77 %tu %tu3lb 3lbm 75. Ias is enclosed enclosed in a c+linder c+linder with with a wei(hed piston piston as the the top boundar+ boundar+.. /he (as is heated heated and $ e8pands from a volume of 0.0" m at a constant pressure of 200 pa. Calculate the wor done b+ the s+stem. Answer: C A. %. 10 C. 12 '. 1" 7&. A piston= c+linder c+linder s+stem contains a (as which e8pands under under a constant constant pressure of of 1200 lb3ft lb3ft 2. ?f the piston is displaced 1 ft durin( the process, and the piston diameter is 2 ft. what is the wor done b+ the (as on the piston* piston* A. 17& 7& ft=l ft=lbb %. 2$7 ft ft=lb C. $7& ft ft=lb '. "000 000 ft=l ft=lbb 77. Ias enclos enclosed ed in a c+linder c+linder with with a wei(ht wei(hted ed piston piston as the the top bound boundar+ ar+.. /he (as is heated heated and $ $ e8pands from a volume of 0.0" m to 0.10 m . /he pressure varies such that ! constant and the initial pressure is 200 !a. Calculate the wor done b+ the s+stem. Answer: B A. &.0 %. 7.$$ C. #.5# '. 12
7. ?n an an isent isentrop ropic ic proc process ess,, !1 200 psi, ! 2 $00 psi and / 1 700 ºE. Find / 2 usin( 1.". Answer: C
A. %. C. '.
57& ºE &0 ºE 7& ºE 5#0 ºE
7#. 4itro(en : 1."; 1."; is e8panded isentropicall+ isentropicall+.. ?ts temperature chan(es chan(es from &20 ºF to &0 ºF. ºF. Find the pressure ratio :!13!2;. Answer: B A. 0.0 %. 12.#1 C. 2&.2 '. $5."7 0. 4itro(en 4itro(en is e8panded e8panded isentropical isentropicall+ l+.. ?ts temperatur temperaturee chan(es from &20 ºF to &0 ºF. /he volumetric volumetric ratio is : 132; &.22 and the value of E for nitro(en is 0.077 %tu3lb mºE. )hat is the wor done b+ the (as* Answer: A A. =110 =110.1 .1 %tu3 %tu3lb lbm %. 120. 120.27 27 %tu3 %tu3lb lbm C. 110.1 10.1 %tu %tu3l 3lbbm '. =120 =120.2 .277 %tu %tu3lb 3lbm 1. ?f the ºF scale scale is twice twice the ºC scale, scale, what is the readin( readin( in in the Fahrenhei Fahrenheitt scale* Answer: B A. 1&0 ºC %. $20 ºC C. 1"0 ºC '. 20 ºC 2. )ater enters enters the condenser condenser at $0 ºC and leaves leaves at &0 ºC.)hat ºC.)hat is the temperature temperature differen difference ce in ºF* Answer: C
A. %. C. '.
1&.&7 ".&7 5" 22
$. $. A c+li c+lind nder er and and pist piston on arra arran( n(em emen entt cont contai ains ns satu satura rate tedd wate waterr vapo vaporr at 110 ºC. ºC. /he /he vapo vaporr is compressed in a reversible adiabatic process until the pressure is 1.& @pa. 'etermine the wor done b+ the s+stem per ( of water. At 110 ºC, 6 1 7.2$7 3(=>, 1 251.1 3( and at 1.& @pa, 62 7.2$7" 3(=>, 2 2#50.1 3(=>, / 2 "00 ºC. Answer: B A. =500 =500 3 3(( %. ="$2 3( C. =&$2 3( '. =700 =700 3 3(( ". -elium is compressed compressed isothermall+ isothermall+ from 1".7 psia psia and & ºF. ºF. /he compression compression ratio is is ". Calculate the chan(e in entrop+ of the (as (iven that E -elium -elium 0."#&1 %tu3lb m ºE. Answer: A A. =0.& =0.& %tu3 %tu3lb lbm ºE %. =2.7 =2.7&& %tu %tu3l 3lbbm ºE C. 0.& .& %tu %tu3lb 3lbm ºE '. 2.7& .7& %t %tu3lb u3lbm ºE
5. 6team 6team at at a pres pressur suree of # bar bar :hf 20$1 3(; is (enerated in an e8haust (as boiler from feedwater at 0 ºC :h $$".# 3(;. if the dr+ness fraction of the steam is 0.#&, 'etermine the heat transfer per ilo(ram of steam. Answer: A A. 2$57.& %. $$57.& C. 1$57.& '. 5$57.& &. &. ?f wet wet satu saturate ratedd stea steam m at bar bar :hf( 20" 3(; reuires 2 of heat per ( of steam to completel+ dr+ it, what is the dr+ness fraction of the steam* Answer: C A. 0.7& %. 0.& C. 0.#& '. 0.&& 7. )et satur saturate atedd steam steam at 17 17 bar :h :h f 72 3(, h f( 12#$ 3( ; dr+ness 0.#7 is produced from feedwater at 5 ºC :h $$5.# 3(;. Find the heat ener(+ supplied per (. Answer: C A. "$1 "$1." ."11 3 3( ( %. 1$1 1$1." ."11 3 3(( C. 2$1 2$1." ."11 3 3(( '. $$1 $$1." ."11 3 3( ( . A turbo=(e turbo=(enerat nerator or is supplied supplied with superheat superheated ed steam at a pressure of $0 bar and temperature temperature $50 ºC :h $117 3(;. 3(;. /he pressure of the e8haust steam from the turbine is 0.0& bar :h f 15.2 3(, hf( 2"15 3(; with a dr+ness fraction of 0.. ?f the turbine uses 0.25 ( per second, calculate the power euivalent of the total enthalp+ drop. Answer: B A. 10#.#5 .#5 ) ) %. 20#.#5 .#5 ) C. $0#.#5 .#5 ) '. "0#.#5 .#5 ) ) #. 6team enters enters the the superheater superheaterss of a boiler boiler at a pressure pressure of 20 bar bar :h f #0# 3(, h f( 1#03(, v $ 0.0##57 m 3(; and dr+ness 0.# and leaves at the same pressure at a temperature of $50 ºC :h $1$ $1$ 3 3(, (, v 0.01$& m $3(;. Find the percenta(e increase in volume due to dr+in( and superheatin(. Answer: D A. 12.0" %. 22.0" C. $2.0" '. "2.0" #0. 6team at the rate rate of 500 (3hr is produc produced ed b+ a stead+ flow flow s+stem s+stem boiler boiler from feedwater feedwater enterin( enterin( at "0 ºC. Find the rate at which heat is transformed in Cal3( and of steam 50 Cal3( . Answer: Answer: A A. 275, 275,00 0000 Cal Cal3h 3hr r %. 175, 175,00 0000 Cal Cal3h 3hr r C. $75, $75,00 0000 Cal Cal3h 3hr r '. "75, "75,00 0000 Cal Cal3h 3hr r
#1. 6tean leaves leaves an an industri industrial al boiler boiler at 27." 27." !a !a and 171.& 171.& ºC :h f 727.25 3(, h f( 20"$.2 3(;. A portion of the steam is passed throu(h a throttlin( calorimeter and is e8hausted to the atmosphere when the calorimetr pressure is 101." pa and a temperature of 115.& ºC :h 2707.& 3(;. -ow much moisture does the steam leavin( the boiler contain* Answer: B A. 2.0< %. $.0< C. ".0< '. 5.0< #2. 'urin( 'urin( the pol+tropic pol+tropic process process of an ideal ideal (as, the state state chan(es from from 1$ pa and 5 ºC to 27 !a and 171 ºC. Find the value of n. Answer: A A. 1.$5" %. 1.25$ C. 1.$"5 '. 1.2$" #$. For an ideal (as, (as, what is the specific specific molar entrop+ entrop+ chan(e chan(e durin( durin( an isothermal isothermal process process in which the pressure chan(es from 200 !a to 150 !a* Answer: A A. 2.$# 2.$# 3mo 3mol= l=> > %. 1.$# .$# 3( 3(=> C. $.$# .$# 3( 3(=> '. ".$# .$# 3 3((= > #". )ater ater enters enters the heater heater at 25 ºC and leaves leaves at 0 ºC. )hat )hat is the the temperat temperature ure chan(e chan(e in ºF* Answer: B
A. %. C. '.
55 ## 11 &5
#5. /he suction suction pressure pressure of a pump reads &00 &00 mm h( vacuum. )hat )hat is the absolute absolute pressure pressure in !a* Answer: C
A. %. C. '.
11.$$ $1.$$ 21.$$ "1.$$
#&. ne ilo ilo(ra (ram m of wet stea steam m at a pressur pressuree of bar : v( = 0.2"0" m$3(, vf 0.00111" m $3(; and dr+ness 0.#" is e8panded until the pressure is " bar : v( 0."&25 m $3(, vf 0.0010$& m $3(;. ?f e8pansion follows the law ! n C, where n 1.12, find the dr+ness fraction of the steam at the lower pressure. Answer: A A. 0.#072 %. 0."1#7 C. 0.22&0 '. 0.2"0"
#7. 2.5 liters liters oof oof superhea superheated ted steam steam at 25 25 bar and and "00 ºC ºC : v 0.1252m $3(; is e8panded in an en(ine to a pressure of 0.1 bar : v( 1".&7" m $3(, vf 0.0010102 m $3(; when its dr+ness fraction is 0.#. Find the final volume of the steam. Answer: A A. 1&$. 1&$.7" 7" lite liters rs %. 2&$. 2&$.7" 7" lite liters rs C. $&$. $&$.7" 7" lite liters rs '. "&$. "&$.7" 7" lite liters rs #. A 1.5 ( of of wet steam steam at a pressure pressure of 5 bar :h :h f &"0 3(, h f( 210# 3(; dr+ness 0.#5 is blown into 70 liters of water 12 ºC :h 50." 3(;. Find the final enthalp+ of the mi8ture. Answer: D A. 7".0 ".0 3 3(( %. ".0 ".0 3 3(( C. #".0 ".0 3 3(( '. 10" 3( ##. )et satur saturate atedd steam steam at 1& 1& bar :h :h f 5# 3(, h f( 1#$5 3(; reducin( valve and is throttled to a pressure of bar :hf 721 3(, h f( 20" 3(;. Find the dr+ness fraction of the reduced pressure steam. Answer: C A. 0.$$ %. 0.77$$ C. 0.##$$ '. 0.&&$$ 100. 100. A vessel vessel of volum volume. e.77 m $ contains air and dr+ saturated at a total pressure of 0.0& bar and temperature 2# ºC :! sat 0.0" bar, v $".0 m$3(;. /ain( E for air as 27 3(=>, calculate the mass of steam and the mass of air in the vessel. Answer: A A. 0.25 0.25 (, (, 0.2 0.20" 0" ( %. 0.$5 0.$5 (, (, 0.2 0.20" 0" ( C. 0.25 0.25 (, (, $50 $50 ( '. 0.$5 0.$5 (, (, 0." 0."55 ( ( PROBLEMS IN FLUID MECHANICS
1.
A fluid that has a velocit velocit++ of 1m3s 1m3s have have an euivale euivalent nt head head of9 of9 Answer: A A. 1&.51 m %. 1$.5& m C. 1.$" m '. 11."1 m
2.
/he len(t len(thh of pipe is 1& 1& meters. meters. ?f the the pressur pressuree drop is 50 !a !a for ever+ ever+ $0 m, what what is the total total pressure drop* Answer: C A. 2"0 !a %. 2&0 !a C. 20 !a '. 220 !a
$.
Find the the volume volume flow flow rate rate of water water in J3s J3s if the the power power develop developed ed under under a head head of $20 $20 m is 10,500 10,500 ) and the h+draulic efficienc+ is 5<. Answer: A A. $,#$5 %. $,2#$ C. $,271 '. $,721
".
)ater flows flows in in a pipe pipe with a velocit+ velocit+ of of 10 m3s. m3s. determine determine the the velocit velocit++ head of the water water . Answer: Answer: A
A. %. C. '.
5.1 m &. m 1.5 m .& m
5.
A c+li c+lindr ndrica icall pipe pipe with with water water flow flowin( in( down downwar wardd at 0.02 0.02 m $3s havin( top diameter of 0.0, bottom diameter of 0.0" m and hei(ht of 1.5 m. find the pressure between the pipe. Answer: B A. #".05 ! !a %. 10".0& .0& ! !a C. 12".07 .07 ! !a '. 1$".1 $".100 !a
&.
?n a h+drau h+draulic lic pres presss the lar( lar(ee piston piston has has a cross cross== section sectional al area area A 1 200 cm2 and the small piston has a cross= sectional area A2 5 cm2. ?f the force applied is 250 4 to the small piston. Compute the force actin( on the lar(e piston. Answer: A A. 10 4 %. 12 4 C. 21 4 '. 20 4
7.
A soli solidd materi material al in a cube cube shape shape float floatss in oil oil of densit densit++ 00 (3m (3m $ with one= third of the bloc out of the oil. )hat is the buo+ant force on the cube whose ed(e is 0.75 cm. Answer: A A. 2.20 .207 8 10 10=$ 4 %. 2.5 .51 8 10=$ 4 C. 1.25 .255 8 10=$ 4 '. $.01 .012 8 10 10=$ 4
.
A balloo balloonn havin( havin( a mass mass of "00 ( remain remainss suspend suspended ed motionl motionless ess in the air. air. ?f the air densit densit++ is $ 1.2# (3m , what is the volume of the balloon in cubic meters* Answer: A A. $10 m$ %. $"0 m$ C. 20 m$ '. 270 m$
#.
A bloc bloc of wood wood that that wei(hs wei(hs 71.2 4 and of of specific specific (ravit+ (ravit+ 0.72 0.72 is tied tied b+ a strin( strin( to the the bottom bottom of a tan of water in order to have the bloc totall+ immersed. 'etermine the tension in the strin(. Answer: A
A. %. C. '.
2$.7$ 4 "7.72 4 #".#$ 4 50.25 4
10. A c+lindri c+lindrical cal wooden wooden buo+ of hei(ht hei(ht $ m and mass 0 (, floats floats verticall+ verticall+ in water water. ?f its specific specific (ravit+ is 0., how much will it be depressed when a bod+ of mass 10 ( is placed on its upper surface* Answer: A A. 0.$0 m %. 0."0 m C. 0.$5 m '. 0."5 m 11. 11. /he wei(ht wei(ht of the balloon and and the (as it contains contains is 11.12 11.12 4. ?f the balloon balloon displaced displaced 11$2 11$2 m $ of air and wei(ht of 12.$ 4, what is the acceleration with which the balloon be(ins to rise* Answer: A A. 2."7 m3 m3s2 %. $.7& m3s2 C. 2.0 m3s2 '. $.2" m3 m3s2 12. 'urin( 'urin( a heav+ rain, rain, a $ m 8 ".& m room is flooded flooded to to a depth of 15 cm. /o /o remove the the water :K =$ 1.0 8 10 !a.s;, a pump is used that does the ob in two hours. /he water flows throu(h a horiLontal pipe of radius 0.&" cm and len(th of &.7 m. Compute the (a(e pressure does the pump produce* Answer: A
A. %. C. '.
2.#2 .#2$ ! !a 2.7 .75 !a 1.17 .17& !a 1.25 .25" ! !a
1$. ?f the velocit+ velocit+ of the flow in a 75= mm diameter diameter fire hose hose is 25 cm3s, what is the power power available available in a $0=mm diameter et issuin( from a noLLle attached at the end of the pipe. Answer: A A. 1.$" ) %. $.2" ) C. 1.25 ) '. 2.$" ) 1". A mercur+ mercur+ barome barometer ter stands stands 7&2 mm. A (as (as bubble, bubble, whose whose volume volume is $$ cm $ when it is at the bottom of the lae "5.7 m deep rises to the surface. Compute the volume at the surface of the lae. Answer: A
A. %. C. '.
17 cm$ 25 cm$ 520 cm$ $20 cm$
15. A ".# ft$ of water are compressed to 5000 psi(. )hat is the volume decrease if the temperature is &0 ºF* Assume the avera(e bul modulus of elasticit+ of $11000. $11000. Answer: A $ A. 0.0# ftft %. 0.0## ft$ C. 0.07# ft$ '. 0.0&# ftft$ 1&. A c+lind c+lindrical rical tan tan havin( havin( a diameter diameter 1.5 m and a hei(ht " m is open at one one end and closed closed at the other end. ?t is placed below the water surface with its depth of the water inside the tan is 1. m* Answer: C
A. 5.#0cm %. 7.0 cm C. &.25 cm
'. &.0 cm 17. 17. A 70.7 70.7"" J3s J3s :150 :150 ft$3min.; of water is flowin( in a round pipe such that the flow remains laminar. Considerin( that the critical Ee+noldMs number to be 2000, what is the diameter of the pipe necessar+ to ensure laminar flow. :4ote9 inematic viscosit+ of water is ".75 8 10 =5 ft 23s;. Answer: A
A. %. C. '.
$$.50 ftft "1.7 ft 12.5 ft $7.5 ftft
1. )ater is flowin( flowin( in a pipe of var+in( var+in( cross= sectiona sectionall area, and at all points the water complete completel+ l+ 2 fills the pipe. /he cross= sectional area N point 1 is 0.00 m , and the velocit+ is $.5 m3s. Compute the fluidMs fluidMs velocit+ at point 2 where the cross= sectional area is 0.0&0 m 2. Answer: A A. ".&7 m3 m3s %. 5.22 m3s C. 2.57 m3s '. $.25 m3 m3s 1#. A sealed sealed tan containi containin( n( seawater seawater to a hei(ht of 12 m also contains contains air above above the water at (a(e (a(e pressure of 5 atm. )ater )ater flows out from the bottom bottom throu(h a small hole. Calculate the the efflu8 speed of the water. 4ote9 Os.w 1.0$ 8 10 $ (3m$. Answer: A A. $".#2 m3 m3s %. "5.2" m3s m3s C. 20."5 m3s m3s '. $5."5 m3 m3s 20. A c+lindr c+lindrical ical bucet, bucet, open at the top, 0.200 0.200 m hi(h and 0.100 m in diameter diameter.. A circula circularr hole with 2 cross= section area 1.0 cm is cut in the center of the bottom of the bucet. )ater flows into the bucet from a tube above it at the rate of 1.$0 8 10 =" m$3s. -ow hi(h will the water in the bucet rise* Answer: A A. .&2 cm cm %. ".&7 cm C. 2.52 cm '. 1.25 cm cm 21. @odern @odern airplane airplane desi(n desi(n calls calls for a lift due to the the net force of the the movin( air air on the win( win( of about 2000 43m2 of win( area. Assume the air densit+ :densit+ 1.2 (3m $; flows past the win( of an air= craft with streamline flow. ?f the speed of flow put the lower win( surface is 1"0 m3s, what is the reuired speed over the upper surface to (ive a lift of 2000 43m 2* Answer: A A. 151 m3s %. 170 m3s C. 172 m3s '. 1"0 m3s 22. )ater leaves leaves a faucet with a downward downward velocit+ velocit+ of $ m3s. As As the water falls falls below the faucet faucet it accelerates with acceleratin( (. the cross sectional area of the water stream leavin( the faucet is 1.0 cm2. )hat is the cross= sectional area of the stream 0.50 m below the faucet* Answer: A A. 0.&# cm cm2 %. 0."5 cm2
C. 0.57 cm2 '. 0.25 cm cm2 2$. /he dens densit+ it+ of ice ice is #17 #17 (3m (3m$, and the appro8imate densit+ of sea water in which an iceber( floats $ is 1025 (3m . )hat fraction of iceber( is beneath the water surface* Answer: A A. 0.# %. 0.71 C. 0."5 '. 0.2# 2". A hose hose shoots shoots water strai(h strai(htt up a distance of 2.5 m. /he /he end openin( openin( on the hose has an area area of 2 0.75 cm . -ow much water comes out in min.* Answer: A A. $1.5 1.5 liliters ers %. "1.5 1.5 lit liters ers C. 20.5 0.5 lit liters ers '. 1$0. 1$0.55 lite liters rs 25. A barrel barrel contains contains a 0.150 0.150 la+er of oil floatin( floatin( on water water that is 0.$0 0.$0 mm deep. ?f the densit+ densit+ of the the $ oil is &00 (3m , what is the pressure :(a(e; at the oil=water interface* Answer: A A. $ !a %. 7"2 !a C. #00 !a '. #2" !a 2&. A hollow hollow sphere sphere is held below below the surface surface of a fresh water lae lae b+ a cable anchored anchored to the bottom bottom $ of the lae. /he sphere has a volume of 0.$00 m , and the tension on the cable is #00 4. Calculate the buo+ant force e8erted b+ the water on the sphere, and the mass of the sphere. Answer: A A. 2,#" 2,#"$$ 4, 4, 20 20.2 .255 ( %. $."2 $."211 4, 4, "$5. "$5.25 25 ( C. 1,57 1,57&& 4, 4, $07. $07.$5 $5 ( '. 2,5& 2,5&77 4, 4, $02 $02." ."55 ( 27. )hat is the force force actin( actin( on one side of the tan tan movin( upward upward with with an acceleratio accelerationn of ".7 m3s 2 when it is filled with oil whose specific (rsvit+ is 0.752 and hei(ht of 1.$ m for the bottom of the tan. Answer: A A. 11.#& .#& 4 %. 15.72$ 4 C. 1".572 4 '. 17."57 4 4
2. A vertical vertical slidin slidin(( (ate is bein( submer submer(ed (ed in a 10 meter water. water. /he (ate is 5 m wide and # m hi(h and wei(hs 50 4. )hat vertical force is needed to ust lift this (ate considerin( that the coef. f friction between the (uides and ed(es is 0.25. :4ote9 4e(lect %uo+ant Force ;. Answer: C A. &75 4 %. 7&5 4 C. &57 4 '. 75& 4
2#. A bloc bloc of wood floats floats in water with with 7 inches proectin proectin(( above the water water surface. surface. ?t is then placed in alcohol of sp. Ir. 0.2, and proected " in. above the surface. )hat is the sp. Ir. f the bloc* Answer: A
A. %. C. '.
0.&& 0.# 0.& 0.7$
$0. -ow far below the water surface surface should a vertical vertical suare 1 m on a side with two two sides horiLontal horiLontal to be immersed so that the center center of pressure will be 70 mm below below the center of (ravit+* Answer: A A. 0.&# m %. 0.72 m C. 0.57 m '. 0.7 m $1. A conical conical reducin( reducin( sections sections connects connects an e8istent e8istent 10.1& cm diameter diameter pipeline pipeline with a new 5.0 cm diameter line. At &#.$0 !a static pressure under no=flow conditions, what is the tensile force is e8erted on the connectors at oint A assumin( no end restraint from the pipe. Answer: A A. ".1# 4 %. 5.12 4 C. $.2$ 4 '. ".15 4 $2. An oil oil flowin flowin(( at the the rate rate of 0.001 0.001 m $3s throu(h an cm diameter pipe has a inematic viscosit+ of 2 8 10=5 m23s and an specific (ravit+ of 0.5. )hat is the centerline velocit+* Answer: A A. 0.$# .$# m3 m3s %. 0.&7 .&7 m3s m3s C. 0.2$ .2$5 m3s m3s '. 0.5" .5"7 m3 m3s $$. An ore sample sample wei(hs wei(hs 15 4 in air. air. )hen the ample ample is suspen suspended ded b+ li(ht li(ht chord and totall totall++ immersed in water, the tension in the chord is 10.0 4. find the /otal volume of the sample. Answer: D
A. %. C. '.
2.5" 81 810=" m$ $."5 810=" m$ 5.&7 810=" m$ ".2 81 810=" m$
$". )ater ater at 20 ºC is flowin( flowin( in a pipe of radius radius 1.0 cm. cm. /he viscos viscosit+ it+ of water water at 20 ºC is 1.005 1.005 centipoise. ?f the flow speed at the center is 0.200 m3s and the flow is laminar, find the pressure drop de to viscosit+ alon( a 5 m section pipe. Answer: A A. "0.2 !a !a %. 12.5 !a C. 1$."5 !a '. "5.77 !a !a $5. )hat is the the specific specific (ravit+ (ravit+ of a solid sphere sphere that has a radius radius of 15 mm and a mass of 0.0$ (* (* Answer: A
A. %. C. '.
2.&7 $.12$ 2.157 $.1"5
$&. A piece piece of cor has a specific specific (ravit+ (ravit+ of 0.25 and wei(hs wei(hs " lb in air. air. ?f the wei(ht densit+ densit+ of water water is &2." lb3ft $. Compute the volume of the cor. Answer: C A. 0.2 ftft$ %. 0.2" ft$ C. 0.2& ft$ '. 0.$ ftft$ $7. At a hei(ht 10,000 10,000 m :$$,000 ft; above above the sea level, atmospheri atmosphericc pressure pressure is about 210 mm of -(. 2 )hat is the resultant normal force on a &00 cm window of an airplane fl+in( at this hei(ht when the h+drostatic conditions and a pressure inside the plane of 7&0 mm of mercur+ and densit+ of mercur+ is 1$,&00 (3m $* Answer: A A. "."0$ 4 4 %. $."07 4 C. 5.721 4 '. 2.7"1 4 4 $. An atmospheri atmosphericc pressure pressure of 101.$25 101.$25 !a will be supported supported b+ how how much hei(ht hei(ht of water* Answer: A
A. %. C. '.
10.$2 m 15."2 m 1$.2$ m 15."5 m
$#. A smal smalll bloc bloc of wood wood of dens densit+ it+ 0." 0." 8 10 $ (3m$ is submer(ed in water at a depth of 2.# m. Find the acceleration of the bloc toward the surface when the bloc is released in a water whose viscosit+ is to be ne(li(ible. Answer: A A. 12.7 m3 m3s2 %. 11." m3 m3s2 C. 1".77 m3s m3s2 '. 10.77 m3 m3s2
"0. /he surface surface tension tension of water is 0.07 43m. 43m. Find the wei(ht wei(ht of water support supported ed b+ surface surface tension tension in a capillar+ tube with radius of 0.10 mm. Answer: A A. "" K4 %. 5" K4 C. $5 K4 '. 57 K4 "1. A submarin submarinee is 100 m lon(. lon(. /he shape of its hull is rou(hl+ rou(hl+ c+lindr c+lindrical ical with with a diameter diameter of 15 m. )hen it is submer(ed, it cruises at a speed of about "0 nots or appro8imatel+ 20 m3s. Compute the re+noldMs number, if the viscosit+ is 1.0 8 10 =$ !a.s. Answer: A A. $ 8 10
%. " 8 10 C. 5 8 10 '. 2.5 8 10 "2. "2. /he /he et disch dischar ar(e (ess water water at the the rate of 0.10 0.10 m $3s and at a speed of 1 m3s to stationar+ plate. 'etermine the force on the plate. Answer: A A. 200 4 %. 2000 4 C. 100 4 '. 2500 4 "$. A h+drauli h+draulicc lift is to be used to lift a truc truc wei(hin( wei(hin( 5000 lb. lb. )hat is the pressure pressure :(a(e; :(a(e; must be applied to the oil if the diameter of the lar(e piston is 12 in. Answer: A A. "".2 ps psi %. "2.7 psi C. 1".5 psi '. 17.& ps psi "". -ow hi(h hi(h does does mercur mercur++ barom baromete eterr stand standss on a da+ when atmosp atmospher heric ic pressure pressure is #.& #.& !a considerin( that the specific (ravit+ of mercur+ is 1$.&. Answer: A A. 7$# mm %. "00 mm C. 7&0 mm '. 5"0 mm "5. A ri(id ri(id container container is closed closed at one end and measure measuress in. diameter diameter b+ 12 in. lon( /he /he container container is held verticall+ and is slowl+ moved downward until the pressure in the container is 15.5 psia. )hat will be the depth of the water surface measure from the free water surface* Answer: C A. #.2 in %. 12 in C. 22 in '. #. in "&. )hat is the e8pected head loss loss per mile of of a closed circular circular pipe with 17 in. inside inside diameter friction factor of 0.0$ when $$00 (al3min of water flow under pressure* Answer: C A. 0.007 ftft %. 0.&"7 ft C. $ ft '. $5.0 ftft "7. /he fluid fluid in a manometer manometer tube tube is &0< water water and "0< alcohol alcohol :6.I 0.;. 0.;. )hat is the the manometer manometer fluid hei(ht difference if a &.2 psi pressure is applied across the two ends of a manometer* Answer: A
A. %. C. '.
215 in $1& in 151 in 1.& in in
". A 150 mm diameter diameter pipe pipe carries 1.$ J3s J3s of water. water. /he pipe branches branches into into two pipes one is 50 mm in diameter and the other is 75 mm. )hat is the velocit+ in 75 mm pipe if the velocit+ of the flow in the 50 mm pipe is 10 m3s* Answer: A A. 1$.#& m3 m3s
%. 15.&7 m3s m3s C. 17.25 m3s m3s '. 1#."$ m3 m3s "#. A (as flows flows throu(h throu(h a suare conduit, conduit, at the entrance entrance the conduit conduit sides sides are 10 cm, the velocit+ velocit+ is $ 7.55 m3s, and the (as mass densit+ is 1.0# (3m . At the e8it, the conduit sides are 25 cm, and the velocit+ of the flow is 2.02 m3s. Find the densit+ of the (as at the e8it section considerin( that the (as is compressible. Answer: C A. 0.&5# .&5# (3 (3m m$ %. 0.&5 .&511 (3 (3m m$ C. 0.&51 .&51 (3 (3m m$ '. 0.&1 .&155 (3 (3m m$ 50. A hose hose shoots water water strai(ht up for a distance of 2.5 m. /he end openin( on the hose has an area of 0.75 cm2. -ow much water come out in 1 hour. Answer: A A. 1.# m$ %. 0.7 m$ C. 1.&7 m$ '. 2.5& m$ INTERNAL COMBUSTION ENGINE
1.
An // // n(ine n(ine has a clearan clearance ce volume volume of 7<. ?t produces produces $00 $00 ) of power power.. )hat is is the amount amount of heat reected in )* Answer: C A. 170 %. 1&0 C. 152 '. 1"5
2.
An air stand standar ardd has a comp compre ress ssio ionn rati ratioo of 20 and a cut= cut=of offf rati ratioo of 5. ?f the the air air pres pressu sure re and temperature are 100 !a and 27 PC, find the wor in 3(. Answer: B A. 27#& %. 21&5 C. 2"$7 '. 2751
$.
'etermine 'etermine the the air=standa air=standard rd efficien efficienc+ c+ of an en(ine en(ine operatin operatin(( on the 'iesel 'iesel c+cle c+cle when the the suction suction pressure is ##.#7 !a and the fuel is inected for &< of the stroe, the clearance volume is < of the stroe. Assume 1.". Answer: A A. &0.07< %. &5.01< C. &7.01< '. &".02<
".
?n an air air standard standard // // c+cle c+cle,, the clearanc clearancee volume volume is 1< 1< of the the displacem displacement ent volume. volume. Find Find the the thermal efficienc+. Answer: C A. 0.52 %. 0.55 C. 0.5$ '. 0.&0
5.
?n an air air standard standard 'iesel 'iesel c+cle, c+cle, compr compressio essionn starts starts at 100 100 !a and and $00 >. >. the compres compression sion ratio ratio is is 1& to 1. /he ma8imum c+cle temperature is 20$1 >. determine the thermal efficienc+. Answer: A A. &0.27< %. &2.27< C. &$.27< '. &".27<
&.
A 'iesel 'iesel en(ine en(ine is operati operatin( n( on a "=stroe "=stroe c+cle, c+cle, has a heat heat rate of 11,$15 11,$15.& .& 3) 3)=hr brae. brae. /he compression ratio is 1$. /he cut=off ratio is 2. sin( 1.$2, what is the brae en(ine efficienc+* Answer: A
A. %. C. '. 7.
.
#.
&$.5 51.2 7$.5 "5.$
/he compres compression sion ratio ratio of of an ideal ideal // // c+cle is is &91. ?nitial ?nitial condi condition tionss are 101.$ 101.$ !a and and 20 PC. PC. Find the pressure and temperature at the end of adiabatic compression. Answer: A A. 12"" 12"".5 .5 !a !a,, 5##. 5##.#& #& > %. 12"" 12"".5 .5 !a, !a, &0 &0 PC PC C. 12"" 12"".5 .5 !a( !a(,, &0 &0 PC PC '. 12"" 12"".5 .5 !a !a,, 5##. 5##.#& #& PC PC An en(ine en(ine opera operates tes on the air= air=sta standa ndard rd // // c+cle. c+cle. /he c+cle c+cle wor is 1000 1000 3(. 3(. )hat )hat is the compression ratio of the en(ine if the ma8imum c+cle temperature is $17$ > and the temperature at the end of isentropic compression is 77$ >. Answer: B A. &.5 %. .5 C. 7.5 '. #.5 /he conditi conditions ons at the the be(innin( be(innin( of of compressio compressionn in an // // en(ine en(ine operatin( operatin( on hot=air hot=air standa standard rd $ with 1.$5 are 101.$25 !a, 0.05 m and $2 PC. /he clearance is < and 15 are added prer c+cle. 'etermine the mean effective pressure. Answer: A A. $2$.# 2$.#77 !a %. "2$.#7 .#7 ! !a C. 22$.#7 .#7 ! !a '. 52$.# 2$.#77 !a
10. /he compressi compression on ratio of an // // c+cle is #. ?f the initial initial pressure pressure is 150 !a, determine determine the the final pressure. Answer: D A. 1,25 1,251. 1.10 10 !a !a %. ",251 ,251.1 .100 !a !a C. 2,251 ,251.1 .100 !a !a '. $,25 $,251. 1.10 10 !a !a 11. 11. /here are supplied supplied "00 "00 per c+cle to an ideal 'iesel 'iesel en(ine en(ine operatin( operatin( on 500 ( air, air, ! 1 100 !a, t1 50 PC. At the end of compression, ! 2 "000 !a. 'etermine the effective pressure of the en(ine. Answer: C A. &57.5 57.577 !a %. "57.57 .57 ! !a C. 557.57 .57 ! !a
'. $57.5 57.577 !a 12. )hat is the final final temperature temperature after after compressio compressionn of a diesel diesel c+cle if the initial initial temperatu temperature re is $2 PC and the clearance is <. Answer: A A. &$." > %. 7&$." > C. #&$." > '. &&$.." ." > 1$. An ?deal 'ual Combustion c+cle c+cle operates on 500 500 (ram of air. air. At the be(innin( of the compression, compression, the air is at 100 !a, "5 PC. ?f r p p 1.5, r c 1.&5, and r 10, determine the c+cle efficienc+. Answer: D
A. %. C. '.
5$.< 5".< 55.< 5&.<
1". /he compres compressi sion on ratio of an en(ine en(ine worin( worin( on the const constant ant volume volume c+cle c+cle is #.$ to 1. At the be(innin( of compression the the temperature is $1 PC and at the end of combustion the temperature is 1205 PC. /ain( /ain( the compression and e8pansion to be adiabatic and the value of as 1.". Calculate the theoretical thermal efficienc+. efficienc+. Answer: A A. 5#.02< %. 5".02< C. 5.02< '. 5&.02< 15. /he compressi compression on ratio in a 'iesel 'iesel en(ine en(ine is 1$ to 1 and the ratio of e8pansion e8pansion is &.5 &.5 to 1. At the be(innin( of compression the temperature is $2 PC. Assumin( adiabatic compression and e8pansion calculate the ideal thermal efficienc+ tain( the specific heats at constant pressure and volume as 1.005 3(=> and 0.71 3(=> respectivel+. respectivel+. Answer: C A. 5"< %. 5&< C. 5< '. 52< 1&. /he stroe stroe of a (as en(ine en(ine which wors wors on the constan constantt volume c+cle c+cle is "50 mm. mm. /he pressure pressure at the be(innin( of the compression is 1.01 bar and at the end of compression it is 11.1 bar. bar. Assumin( compression follows the law ! 1.$& C, calculate the clearance between the piston and c+linder cover at the end of compression in mm of len(th. Answer: C A. 7$.2& mm mm %. $.2& mm C. #$.2& mm '. 10$.2& .2& mm mm 17. 17. /he /he rati ratioo of compr compres essi sion on in a 'ies 'iesel el en(in en(inee is 1& to 1 and and the the temp temper erat atur uree of the air at the the be(innin( of the compression is "# PC. Calculate the temperature at the end of compression assumin( it follows the law ! 1.$" C. Answer: B A. 2&.5$ .5$ PC PC %. 55$.5$ .5$ PC C. "5$.5$ .5$ PC
'. &5$.5$ .5$ PC PC 1. /he stroe stroe of the piston piston in an internal combust combustion ion en(ine en(ine is 0 mm and the clearance clearance is eual to 1.$ 0 mm. /he law of compression is ! C and the pressure at the end of compression is $2 bar. Find the increase of the final pressure caused b+ reducin( clearance b+ 5 mm. Answer: C A. $.2 ba bar %. 1.2 bar C. 2.2 bar '. ".2 ba bar 1#. ?n an internal combusti combustion on en(ine worin( worin( on the constant constant volume volume c+cle, the pressure, pressure, volume volume and temperature at the be(innin( of compression are 101.$25 !a, 11$ liters, "PC respectivel+. respectivel+. 'urin( combustion at constant volume the (as receives #5 of heat. /ain( compression accordin( to the law !1.$7 C, specific heat at constant volume 0.712 3(=> and (as constant E 00.2# 3(=>, calculate the mass of (as compressed. Answer: A A. 0.12$ ( ( %. 0.2"5 ( C. 0.$"& ( '. 0."5& ( ( 20. /he pressure and temperature of the air at the be(innin( be(innin( of compression compression in a diesel en(ine is 111."& 111."& !a and $5 PC respectivel+, and the clearance volume is eual to 7.5< of the piston swept volume. Calculate the pressure at the end of compression assumin( the law of compression if ! 1.$& C. Answer: C
A. %. C. '.
$52. 52.$$ !a ,02 ,02.# .#00 !a !a ",1&& ,1&&.$ .$11 !a !a "1.1 1.11 !a !a
21. /he stroe stroe of a petrol en(ine en(ine is 7.5 mm and the clearance clearance is eual to 12.5 mm. A compressi compression on plate is now fitted which has the effect of reducin( the clearance to 10 mm. Assumin( the compression period to be the whole stroe, the pressure at the be(innin( of compression as #.2# !a and the law law of compression compression !1..$5 C, calculate the pressure at the end of compression before and after the compression plate is fitted. Answer: A A. 1&2. &2.10 10 !a !a %. 152. 52.10 10 !a !a C. 172. 72.10 10 !a !a '. 12. 2.10 10 !a !a 22. /he compression ratio of a petrol petrol en(ine worin( on the the constant volume c+cle is is .5. /he pressure and temperature at the be(innin( of compression are 101.$25 !a and "0 PC and the ma8imum pressure of the c+cle is $,1"1.0 !a. /ain( compression to follow the law ! 1.$5 C, calculate the temperature at the end of compression. Answer: A A. $.#7 .#7 PC PC %. 2.#7 .#7 PC
C. $55.&5 .&5 PC '. 255.&5 .&5 PC PC 2$. /he stroe stroe of an internal internal combustio combustionn en(ine en(ine is 75 mm, the diameter diameter of the c+linder c+linder is 70 mm and $ the clearance volume at the end of compression is $& cm . Assumin( compression follows the law !1..$ C. Calculate the pressure at the end of compression if the initial pressure is #.2# !a. Answer: B
A. %. C. '.
1 @pa 2 @pa $ @pa " @pa
2". A petrol petrol en(ine en(ine worin worin(( on the the consta constant nt volume volume c+cle c+cle has a compress compression ion ratio ratio of # to 1. ?f the pressure and temperature of the petrol=vapor air mi8ture at the be(innin( of compression are ##.$0 !a and $ PC respectivel+. Calculate the temperature at the end of compression assumin( it follows the law ! 1.2" C. Answer: C A. 1$."5 PC PC %. 2."5 PC C. ##.$0 PC '. $." PC PC 25. )hen the piston is movin( up in a two=stroe two=stroe diesel en(ine, the scaven(e ports ports are closed when the piston is &75 mm from the top of its stroe, the pressure and temperature of the air in the c+linder then bein( 1$.0 !a( and "$ PC. /he clearance is eual to &5 mm and the diameter of the c+linder is &50 mm. Calculate the mass of air compressed in the c+linder tain( the atmospheric pressure as 101.$25 !a and E for air as 0.27 3(=>. Answer: B A. 0.21 ( %. 0.$1 ( C. 0."1 ( '. 0.51 (
2&. /he compressi compression on ratio of a compression= compression=i(ni i(nition tion en(ine en(ine is 1" to 1. /he diameter diameter of the c+linder c+linder is 500 mm and the stroe to bore ratio is 1.2 to 1. At the be(innin( of compression the pressure and temperature of the air in the c+linder is 105 !a and 51 PC, and compression follows the law ! n C, where n 1.$5. Calculate the wor done on the air durin( compression. Answer: A A. =57.&# .&# %. =&7.5# .5# C. =7&.5# .5# '. =#5.&7 .&7 27. Ias initiall+ initiall+ at a pressure of 101.$25 !a and temperature temperature of &0 PC under(oes under(oes the followin( followin( c+cle. c+cle. 1=2 Adiabatic compression throu(h compression ratio of ".591. 2=$ -eatin( at constant volume throu(h a pressure ratio of 1.$591. $=" Constant pressure e8pansion to initial pressure. "=1 Constant pressure coolin( to initial volume.
?f Cp 1 3(=> and Cv 0.&7 3(=> for the (as, determine the thermal efficienc+ of the c+cle. Answer: A A. "1."1< %. $#.$#< C. "$."$< '. "5."5< 2. ne ilo(ram of air at a pressure and temperature of 101.$25 !a and 15 PC initiall+ initiall+,, under(oes the followin( process in a c+cle9 1=2 ?sothermal compression to 202.&5 !a 2=$ !ol+tropic compression from 202.&5 !a to "05.$0 !a $=1 ?sentropic e8pansion from "05.$0 !a to initial condition Calculate the heat transfer for process 1 to 2. se E 0.27 3(=> and 1." for air. Answer: A
A. %. C. '.
=57.2# .2# =$0.21 .21 70.$0 100.50 .50
2#. /he compression compression ratio of of an en(ine en(ine worin( on the dual combustion combustion c+cle is 10.7. /he pressure and temperature of the air at the be(innin( of compression is 101.$25 !a and $2 ºC. /he ma8imum pressure and temperature durin( the c+cle is ".15" @pa and 15#$ ºC. Assumin( adiabatic compression and e8pansion, calculate the temperature at the end of compression. Answer: B A. "1".1" .1" ºC ºC %. 51".1" .1" ºC C. $1".1" .1" ºC '. &1".1" .1" ºC ºC $0. ?n an tto tto en(ine if the compression ratio ratio is 5.5, 5.5, what is the percent clearance* Answer: A A. 22.22< %. $1.11< C. 1#.&"< '. 25.$"< $1. /he efficienc efficienc++ of an tto en(ine en(ine is 55< and the stroe stroe volume volume is $5 liters. liters. ?f the heat added at the be(innin( of the combustion combustion is 12.& , calculate calculate the mean effective effective pressure. Answer: C A. 1#" !a %. 1 !a C. 1# !a '. 1" !a $2. Ias is compresse compressedd in an internal internal combustio combustionn en(ine en(ine accordin( accordin( to the ! 1.$& C. if the initial and final temperatures of the (as are $0 ºC and $2 ºC respectivel+, calculate the compression ratio. Answer: D
A. %. C. '.
5.51 &.51 7.51 .51
$$. ?f the volumes volumes at the end of compres compressio sionn and at the be(inni be(innin( n( of e8pans e8pansion ion in an ideal ideal 'iesel 'iesel $ $ en(ine are 0.015 m and 0.0"0 m respectivel+. respectivel+. )hat is the cut=off ratio* Answer: B
A. %. C. '.
1.&7 2.&7 2.5" 1.5"
$". /he pressure pressure ratio durin( durin( the constant constant volume volume portion portion of combustion combustion in a 'ual Combusti Combustion on en(ine en(ine is 1.5. ?f the pressure at the end of the constant volume addition of heat is ", what is the pressure at the be(innin(* Answer: C A. $.&7 @p @pa %. & @pa C. 2.&7 @pa '. 7 @pa $5. ?f the compressio compressionn ratio and the cut=off cut=off ratio ratio of a 'iesel en(ine en(ine are 15 and $ respective respectivel+ l+,, what is the e8pansion ratio* Answer: B A. " %. 5 C. & '. 7 $&. At the be(innin( be(innin( of compression compression in an ideal dual combustion combustion c+cle, c+cle, the worin( fluid is 2 lbs of air air at 1".7 psia and 5 ºF. /he compression ratio is .5, the pressure at the end of the constant volume addition of heat is "50 psia, and there are added 105 %tu durin( the constant pressure e8pansion. Find the pressure ratio and the percenta(e clearance* Answer: A A. 1.5$ 1.5$,, 1$.$ 1$.$$< $< %. 1.$1 .$1, 12." 12."22< C. 1.5$ .5$, 12." 12."22< '. 1.$1 1.$1,, 1$.$ 1$.$$< $<
$7. $7. )hat )hat is the the effi effici cien enc+ c+ of the the 'ies 'iesel el n(i n(ine ne if the the heat heat adde addedd duri durin( n( the the cons consta tant nt pres pressu sure re combustion is 1# %tu and the heat reected is # %tu. Answer: B A. "2.&$< %. 52.&$< C. 55.&&< '. "5.&&< $. A 'iesel 'iesel c+cle operates operates with with a compression compression ratio of 1" and with a cu=off cu=off occurrin( occurrin( at 5< of the $ stroe. Find the cut=off ratio, if the initial volume is 1.5 ft . Answer: A A. 1.&" %. 2.&" C. $.&" '. ".&" $#. /he air is compresse compressedd to 135 of its ori(inal ori(inal volume volume in an tto c+cle. c+cle. )hat )hat is the final temperatu temperature re of the air if the initial temperature is 25 ºC. Answer: A A. 2.5 .5 ºC ºC %. $.5 .5 ºC
C. 255.&& .&& ºC '. $55.&& .&& ºC ºC "0. An tto c+cle c+cle operates operates 1 ( of air from 101.$25 101.$25 !a and 25 ºC at the be(inni be(innin( n( of compressio compression. n. ?f the clearance is 15<, find the temperature at the end of compression. Answer: B A. $00 ºC %. "00 ºC C. "50.01 .01 ºC '. $50.01 .01ºC "1. /he compression compression ratio and the cut=off cut=off ratio of an ideal diesel diesel c+cle are 1$ and $ respectivel+. respectivel+. )hat is the c+cle efficienc+ for a cold=air standard value of . Answer: A A. 5$.20< %. "$.20< C. 55.21< '. "5.21< "2. /he efficienc+ efficienc+ of an ideal ideal tto c+cle is "0<. "0<. )hat is is the hot=air hot=air value of of , if the the compression ratio is &.2* Answer: A A. 1.2 %. 1.$ C. 1.25 '. 1.$5 "$. )hat is the clearance of an ideal ideal tto en(ine if the efficienc+ efficienc+ is "0< "0< and 1.$* Answer: B A. 20.2"< %. 22.27< C. 10.2"< '. 12.27< "". An tto c+cle c+cle operates operates a 0.5 lb3s of air from 15 psia and 150 ºF,at ºF,at the be(innin( be(innin( of compressio compression. n. /he compression ratio is ".$D hot air standard 1.$. 'etermine the volume at the end of compression. Answer: B A. 2.75 ftft$3s %. 1.75 ft$3s C. $.75 ft$3s '. ".75 ftft$3s "5. "5. An idea ideall dual dual comb combus usti tion on c+cl c+clee oper operat ates es on 0.&0 0.&0 ( of air air. Find Find the the c+cl c+clee effi effici cien enc+ c+ if the the compression ratio is 12, pressure ratio is 1.&, cut=off ratio 1.5 and 1.$. Answer: B A. "0.71< %. 50.71< C. &0.71< '. "5.71< "&. )hat is the pressur pressuree ratio in an ideal dual dual combustion combustion c+cle c+cle if the pressures pressures at the be(innin( be(innin( and and end of the constant volume portion of combustion are 2500 !a and "000 respectivel+. respectivel+. Answer: C A. 1." %. 1.5 C. 1.&
'. 1.7 "7. ?n an ideal dual dual combustion combustion c+cle c+cle if the cut=off cut=off ratio is 1.5 1.5 and the volume volume at the be(innin( be(innin( of the $ constant pressure portion of combustion is 0.055 m , what is the volume at the end of combustion* Answer: A
A. %. C. '.
0.0&25 m$ 0.0725 m$ 0.025 m$ 0.055 m$
". At the be(innin( be(innin( of compression in an ideal dual dual combustion c+cle, c+cle, the worin( fluid fluid is at #0 ºF. ºF. ?f the pressure ratio and compression ratio are 1.& and 1$ respectivel+, what is the temperature at the be(innin( of the constant constant pressure portion portion of combustion* Answer: C A. 1&. &.&" &" ºF %. 1"#5.05 ºF ºF C. 1##5.05 ºF ºF '. 15&. 5&.&" &" ºF "#. An ideal dual combustion c+cle c+cle operates on 0.&5 0.&5 ( of air. air. At At the be(innin( be(innin( of compression, compression, the air is at 100 !a, "5 ºC. 'etermine the volume at the end of compression if net wor is $00 and the mean effective pressure is 700 !a. Answer: A A. 0.1& m$ %. 0.2& m$ C. 0.12 m$ '. 0.22 m$
50. ?n an ideal ideal dual combust combustion ion c+cle, c+cle, what is the pressur pressuree at the be(inn be(innin( in( of const constant ant pressu pressure re combustion if the pressure rario is 1." and the pressure at the be(innin( of the constant volume portion of combustion combustion is 2500 !a. Answer: B A. $000 psi %. $500 psi C. $200 psi '. $&00 psi 51. ?n an air=standa air=standard rd tto c+cle, c+cle, air enters at 10".7 10".7 !a and 27 ºC. /he compression compression rario rario is 791. ?f the net wor of the c+cle is 120 3(. Calculate the heat supplied in 3(* Answer: A A. 221. 221. 3 3(( %. 122. 22. 3 3( C. 1.2 .222 3 3( '. 2. 2.12 12 3 3(( 52. A diesel diesel en(ine en(ine taes taes in air at 105 !a and 2& ºC subec subected ted to a compressi compression on ratio of of 1#. )hat is the operatin( clearance in percent* Answer: A A. 5.5&< %. &.&&< C. ".5&< '. 7.5&<
5$. /he volumes volumes of states states 1,2 and and $ of a diesel c+cle c+cle operatin operatin(( on a hot air standard standard are $00 $00 cm $, $0 cm$ and #0 cm$ respectivel+. Find the power output if the heat input is 120 ). Answer: A A. 57.&$ ) ) %. 77.&$ ) C. 7.&$ ) '. #7.&$ ) ) 5". An ideal ideal diesel diesel en(ine en(ine operat operates es on a 1 ( of cold air with with a suctio suctionn pressure pressure of 110 110 !a and an initial temperature of "0 ºC. /he compression pressure is $000 !a and the cut=off is at < of the stroe from head=end center of the piston. Calculate the ideal c+cle thermal efficienc+. efficienc+. Answer: C A. 5.5&< %. 5#.55< C. 55.5< '. &5.5&< 55. /he air=stan air=standard dard dual dual c+cle starts starts at 105 !a and 2& ºC. /he compressi compression on ratio is 1191 1191 and the total total heat intae is $00 3(. ?f the heat intae at constant volume is $35 of the total, determine the mean effective pressure in !a. Answer: A A. 2"7.5 "7.5&& !a %. 517.&7 .&7 ! !a C. $"7.$" .$" ! !a '. "57.$ 57.$"" !a
FUELS AND COMBUSTION
1.
A bitu bitumin minous ous coa coall has the the follo followin win(( compos compositi itions ons99 C 71.5 < 7.0< 6 $.&< ) $."< - 5.0< 4 1.$< Ash .2< Calculate for complete combustion the theoretical wei(ht of air reuired in ( air 3( 3(coal. Answer: A A. #.0 %. .0 C. 7.0 '. &.0
2.
Calculate Calculate the the hi(her hi(her heatin( heatin( value value of liuid liuid dodecane dodecane fuel. fuel. /he chemic chemical al formula formula of 'odeca 'odecane ne is C12-2&. Answer: A A. ",2 ",255 55 3 3(( %. 55,&" 5,&"11 3 3( C. &0,22 0,2211 3 3( '. $5,2 $5,2"5 "5 3 3((
$.
Calcu Calculat latee the minimu minimum m volume volume of da+ tan tan of 2 PA!? fuel fuel havin( havin( a fuel fuel consump consumptio tionn of 1 (3s. (3s. Answer: B
A. #".71 m$ %. #7."1 m$
C. #1.7" m$ '. 7#."1 m$ ".
?t is reuire reuiredd to find the the theoret theoretica icall volume volume of air at 20 PC and 100 !a absolu absolute te pressur pressuree to burn one ilo(ram of Franlin Countr+ coal. /he ultimate anal+sis of coal=as=fired is as follows9 C &5.&5< 1.&1< @ois. $< - 5.7< 6 1.51< Ash 5.$&< Answer: B
A. %. C. '.
#."$ m$air 3( 3(coal $ 7."$ m air 3( 3(coal $ ."$ m air 3( 3(coal $ &."$ m air 3( 3(coal
5.
A &50 &50 %-! diesel diesel en(in en(inee uses fuel fuel oil of 2 PA!? PA!? (ravit+ (ravit+,, fuel consumpt consumption ion is0.&5 is0.&5 lb3%-!= lb3%-!=hr hr.. cost of fuel is ! 7.#5 per liter. For continuous operation, determine the minimum volume of cubical da+ tan in cm$, ambient temperature is "5 PC. Answer: C A. ",$7 ",$72, 2,# #00 cm$ %. 5,#7 ,#7,# ,#00# cm cm$ C. 5,2#1 ,2#1, ,0 cm cm$ '. 7,$5 7,$52, 2,7 7## cm$
&.
A lo((in lo((in(( firm in ?sabela ?sabela operates operates a 'iese 'iesell lectric lectric plant to to suppl+ suppl+ its electri electricc ener(+ ener(+ reuirement reuirements. s. 'urin( a 2" hr period, the plant consumed 250 (allons of fuel at 0 PF and produced 2700 w=hrs. ?ndustrial fuel used is $0 PA!? PA!? and was purchased at ! $.00 per liter liter at &0 PF. PF. 'etermine the over= all efficienc+ of the plant. Answer: A A. 2&.0< %. 25.0&< C. 2#.07< '. $0.01<
7.
A circul circular ar tan "5 "5 ft lon( lon( and 5.5 5.5 ft diameter diameter is used used for for oil stora(e stora(e.. Calculate Calculate the the number number of da+s da+s the suppl+ tan can hold for continuous operation at the followin( conditions. 6team flow 200lb3hr 6team dr+ and saturated at 200 psia Feedwater temperature 2$0 PF %oiler efficienc+ 75< Fuel oil $" PA!? Answer: A
A. %. C. '. .
15.21 5.21 da+ da+s 1&.2$ da da+s 17.57 da da+s 1#.2& #.2& da+ da+s
Jiuid c ctane :C :C-1; fuel is burned with ideal proportion of air. Calculate the ideal air=fuel ratio b+ wei(ht. Answer: C A. 1$.72 ( (air 3( 3(fuel %. 1".5& (air 3( 3(fuel C. 15.05 (air 3( 3(fuel '. 10.&# ( (air 3( 3(fuel
#.
A t+pi t+pica call ind indus ustr tria iall fue fuell oil oil,, C 1&-$2 with 20< e8cess air, b+ wei(ht. Assumin( complete o8idation of the fuel, calculate the actual air=fuel ratio b+ wei(ht. Answer: A A. 17.5& ( (air 3( 3(fuel %. 15.7& (air 3( 3(fuel C. 1&.75 (air 3( 3(fuel '. 17.&5 ( (air 3( 3(fuel
10. /he ultima ultimate te anal+si anal+siss of coal coal is (iven (iven below9 below9 C &.5< 6 1.5< Ash 12.0< - 2.5< $.5< Calculate the hi(her heatin( value of coal. Answer: D A. 25,$ 25,$00 00 3 3(( %. 2,$0 ,$000 . .( C. 27,$0 7,$000 3 3( '. 2&,$ 2&,$00 00 3 3(( 11. 11. Fuel oil in a da+ tan for use of an industri industrial al boiler is tested tested with h+dromete h+drometerr. /he h+drometer h+drometer readin( indicates a 6.I 0.#2" when the temperature of the oil in the tan is $5 PC. Calculate the hi(her heatin( value of the fuel. Answer: A A. "$, "$,52 52.1 .1$$ 3 3(( %. 5$, 5$,52 52.1 .1$$ 3 3(( C. 5,$ 5,$52 52.1 .1$$ 3 3(( '. ",$ ",$52 52.1 .1$$ 3 3((
12. A steam steam (enerators (enerators burns burns fuel oil with with 20< e8cess air air. /he fuel oil ma+ be represent represented ed b+ C 1"-$0. /he flue (as leaves the preheater at 0.$1 @pa. Find the minimum stac temperature to avoid condensation. Answer: A A. 7$ PC %. &$ PC C. $ PC '. 5$ PC 1$. Iaseous Iaseous fuel fuel mi8ture mi8ture has a molal anal+sis9 anal+sis9 -2 1"< C-" $< C 27< 2 0.&< C2 ".$5< 42 50.#< 'etermine the air=fuel ratio for complete combustion on molal basis. Answer: A A. 2.1$0 %. $.2$0 C. 1.2$$ '. 1.1$0 1". ?n a boile boilerr desi(n desi(n,, it is desira desirable ble to have the flue (as e8it tempera temperatu ture re above the dew point. point. stimate the dew point temperature of the flue (as produced b+ combustion havin( the (ravimetric anal+sis of9 42 71."< 2 $.&1< C2 20.$5< -2 ".20< Assume that air infiltration and leaa(e are ne(li(ible. Answer: A
A. %. C. '.
$# ºC "1 ºC "2 ºC "$ ºC
15. ?f the theore theoreti tical cal air=fu air=fuel el ratio is 15, what is the appro8i appro8imat matee hi(he hi(herr heatin heatin(( value value in 3( 3( fuel* Answer: A
A. %. C. '.
"&,7 "&,755 55 3 3(( 5&,75 &,7555 3 3( "5,7& 5,7&55 3 3( 55,7 55,7&5 &5 3 3((
1&. /here /here are 20 ( of flue (ases (ases formed formed per ( of fuel fuel oil burned burned in the combust combustion ion of a fuel fuel oil C12-2&. )hat is the e8cess air in percent* Answer: A A. 20.17 %. 1&.5& C. 2&.&7 '. .21 17. A diesel diesel electric electric plant suppli supplies es ener(+ ener(+ for @eralco. @eralco. 'urin( a 2" hr period, the plant plant consumed consumed 200 (allons of fuel at 2 ºC and produced $#$0 )=hr. ?ndustrial fuel used is 2 ºA!? and was purchased at ! 5.50 per liter at 15.& ºC. )hat should the cost of fuel be produce one )=hr* )=hr* Answer: A
A. %. C. '.
! 1.05 ! 1.10 ! 1.0&# ! 1.00
1. A fuel fuel oil is burned burned with 50< 50< e8cess e8cess air. air. )hat is the volume volume rate rate of flow flow in m $3min of the wet products at a pressure of 102 !a and a temperature of $50 ºC when the fuel is burned at the rate of "5 (3min* Assume that the combustion reuirements of the fuel oil are similar to those of C 12-2&. Answer: A
A. %. C. '.
1&5 $52& 2"&2 "5&$
1#. A flue flue (as has has the follow followin( in( volumet volumetric ric anal+si anal+sis9 s9 C-" &< C2-& $2< Assume complete combustion with 15< e8cess air at 101.$25 !a, 21 ºC wet bulb and 27 ºC dr+ bulb. )hat is the the partial pressure of the water water vapor in !a* Answer: D A. #.&2 %. 12.1 C. 17.2 '. 15.#" 20. /he follow followin( in( is is an anal+s anal+sis is of coal coal in percent9 percent9 C 7" 2 61 -2 & 42 1.& Ash #." ?f burned in a boiler, boiler, the coal produces the followin( rsat anal+sis in percent9 C2 12 2 &.5
C 0.1 /he refuse contains 0.00 ( of carbon per ( of coal burned. 'etermine the percenta(e of e8cess air used. Answer: A A. "5.&< %. "&.5< C. 5".&< '. 5&."< 21. 21. A (aseo (aseous us mi8tur mi8turee has has a dew dew poin pointt temp temper erat atur uree of 15 ºC. ºC. the the tota totall pres pressu sure re is 1"$.2 1"$.277 !a. !a. 'etermine the amount of water vapor present in 100 moles of the mi8ture. 4ote9 saturation pressure pressure at 15 ºC is 1.7051 !a. Answer: A A. 1.10 %. 2.1# C. 1.1# '. 2.0
22. A coal coal fired utilit+ utilit+ boiler boiler has the followin followin(( characteris characteristics9 tics9 Coal Freed Eate Q Q Q Q Q Q Q Q Q Q Q &,#"0 (3hr (3hr lectric !ower Eatin( Eatin( Q Q Q Q Q Q Q Q 50 @) Eefuse Eemoval Eate Q Q Q Q Q Q Q Q "10 "10 (3hr Carbon in EefuseQ Q Q Q Q Q Q Q Q Q $0< ltimate Anal+sis in percent9 C 7&.5& 2 7.70 6 2."" -2 5.50 42 1.70 6i &.10 -eatin( value of coal is $2,77$ 3( ?f stac (as particle collectors are reuired to meet the limit of 0.0"$ ( particulates per million ( of fuel feed set b+ nvironmental mana(ement %ureau under the urisdiction of the '4E, what efficienc+ must the collection s+stem have* @olecular wei(ht of 6 i 2.0#. Answer: A A. ##.## #.#### ##5$ 5$< < %. #.## #.#### ##5$ 5$< < C. 7#.## #.#### ##5$ 5$< < '. &#.## #.#### ##5$ 5$< < 2$. /he dr+ e8haust (as from oil en(ine en(ine has the followin( followin( (ravimetric (ravimetric anal+sis9 anal+sis9 C2 21.&< 42 7".2< 2 ".2< 6pecific heats at constant pressure for each component of the e8haust (as in Cal3(ºC are9 C2 0.20$ 42 0.2" 2 0.21#
Calculate the specific (ravit+ if the molecular wei(ht of air is 2.#7 (3( mol. Answer: A A. 1.055 %. 1.155 C. 1.255 '. 0.#5 2". A coal coal fired steam boiler boiler uses $000 $000 ( of coal per hour. hour. Air reuired reuired for combustio combustionn is 15.5 ( per coal at a barometric pressure of #.2 !aa. /he flue (as has a temperature of 25 PC and an avera(e molecular wei(ht of $0. Assumin( an ash loss of 11< and an allowable (as velocit+ of 7.5 m3s, find the diameter of the chimne+. chimne+. Answer: A A. 1. m %. 1.&" m C. 2. m '. 2.&" m 25. A certai certainn coal has has the followin followin(( ultimate ultimate anal+sis anal+sis99 C 70.5< - ".5< 2 &< 42 1.0< 6 $.0< Ash 11< @oisture "< A stoer fired boiler of 175,000 (3hr steamin( capacit+ uses this coal as fuel. Calculate the volume of air in m $3hr with air at &0 PF :15.& PC; and 1".7 psia :101.$25 !a; the coal is burned with $0< e8cess air. %oiler efficienc+ of 70< and factor of evaporation of 1.10. Answer: A A. 212, 212,& &1. 1.0" 0" m$3hr %. 221, 21,&1 &1.0 .0"" m$3hr C. 21,2 1,2&1 &1.0 .0"" m$3hr '. 21, 21,2& 2&1. 1.0" 0" m$3hr 2&. @ethane @ethane (as burn completel+ completel+ when when supplied supplied with $0 percent percent e8cess dr+ air. air. /he (aseous (aseous products products are cooled at $2 PC and 1 atm pressure. 'etermine the mass of moisture condensed per ( fuel. Answer: D
A. %. C. '.
1.$02 1.#2" 1.1& 1.&1"
27. A dies diesel el power power plan plantt consume consumedd 1 m $ of fuel with $0 PA!? at 27 PC in 2" hrs. Calculate the fuel rate in (3hr. Answer: A A. $&.21 %. 2&.25 C. 2#.$" '. $#."2 2. A coal has has the the followin followin(( ultimate ultimate anal+sis9 anal+sis9 C &0< -2 &< Ash 5< 42 5< 2 #< @oisture < 'etermine the actual air=fuel ratio usin( 20< e8cess air. Answer: A A. 10.&& ( (air 3( 3(coal %. 11.&& ( (air 3( 3(coal C. 12.&& (air 3( 3(coal '. #.&& (air 3( 3(coal
62 7<
2#. /he ultimate anal+sis of a petroleum fuel is 7.1< carbon and 12.#< h+dro(en. A certain test of dr+ products of combustion (ives the followin( anal+sis b+ volume9 12< C 2D 0.$0< CD ".&< 2D $.1< 42. Calculate the number of atoms of carbon and h+dro(en of the h+drocarbon fuel. Answer: A
A. %. C. '.
n 7.2& 7.2&,, m 12. 12.#0 #0 n .2& .2&,, m 7.2 7.2&& n .2& .2&,, m 1$. 1$.## n 1$.#0 1$.#0,, m .2 .2&&
$0. /he anal+sis anal+sis of natural natural (as fuel used used in a (as turbine power power plant has the the followin( followin( percenta( percenta(es es b+ volume9 C-" 0< C2-" 5< -2 10< C 2< and the remainin( non=combustible (ases. Find the volume of air supplied per hour if the (as consumption is 20,000 m $3hr assumin( "0< e8cess air. Answer: A A. 2",50 ,500 m$3hr %. $",50 ,500 m$3hr C. 2&0,00 ,000 m$3hr '. $&0,00 ,000 m$3hr $1. A diesel power plant plant uses fuel fuel with heatin( heatin( value of "$,000 3(. 3(. )hat is the densit+ of the fuel at 25 PC* Answer: C A. "0 (3m$ %. 7$ (3m$ C. #70 (3m$ '. #"0 (3m$ $2. Calculate Calculate the calorific calorific value value of coal which has the followin( followin( anal+sis9 anal+sis9 Carbon Carbon 1<, -+dro(en -+dro(en 5<, 8+(en 5.&<, 6ulfur 1< and the remainder is ash content. Answer: A A. $$,& $$,& .$ .$55 3 3(( %. $2,1 $2,1$5 $5." ."55 3 3(( C. 12," 12,"5& 5&.$ .$"" 3 3(( '. $2," $2,"57 57." ."55 3 3(( $$. )hat is the the calorific calorific value and the the minimum minimum mass of air reuired reuired per ilo(ram ilo(ram of fuel oil oil which is composed of 5.2< carbon, 12< h+dro(en, 1.&< o8+(en and 1.2< impurities. Answer: A A. 1$.7 ( (air 3( 3(coal %. 1".55 (air 3( 3(coal C. 12.57 (air 3( 3(coal '. 15.75 ( (air 3( 3(coal $". A petrol has the followin( anal+sis anal+sis 5.5< carbon, 1"."< h+dro(en, h+dro(en, and 0.10< sulfur. sulfur. Calculate the volume of air at 1.0 bar and 15 PC reuired for perfect combustion of 1 ( of the fuel. 4ote9 E air 0.27 3(=>. Answer: A A. 12.2" m$3 (fuel %. 1$."5 m$3 (fuel C. 15.5" m$3 (fuel '. 1".57 m$3 (fuel $5. A fuel used used in a boiler boiler contains contains &.1< carbon, carbon, 12.5< h+dro(en h+dro(en,, and 0."< o8+(en and 1< sulfur sulfur. /here are "0< e8cess air supplied to the furnace and the fuel rate is "00 (3hr. Calculate the mass
of air and the heat ener(+ transferred to the air per hour if it enters the air heater at 1 PC and leaves at 1$0 PC. 4ote9 C p 1.003(=>. Answer: A A. 7,#7".2& 7,#7".2& 3(, 3(, #0,0#$.12 #0,0#$.12 3( 3( %. ,&7. ,&7."5 "5 3( 3(,, #0,0"5 #0,0"5.12 .12 3( 3( C. 7,$"5. 7,$"5.$5 $5 3( 3(,, &70,0$5 &70,0$5."5 ."5 3( 3( '. ,#7.7& ,#7.7& 3(, 3(, 5&7,0#.57 5&7,0#.57 3( 3( $&. A fuel has the followin( constituents9 constituents9 Carbon 5<, -+dro(en -+dro(en 1$<,8+(en 1$<,8+(en 2<. )hen burnin( this this fuel in a boiler furnace the air suppl+ is 50< in e8cess of the theoretical minimum reuired for complete combustion, the inlet temperature of the air bein( $1 PC and funnel temperature is 20 PC. Compute its calorific value, air=fuel ratio and percenta(e of heat ener(+ supplied. Answer: A A. "7,1$$ "7,1$$.0$ .0$ 3(, 3(, 21.2& 21.2& ( ( air 3( 3(fuel %. $5,#7 $5,#7.5" .5" 3(, 3(, 12.21 12.21 (air 3( 3(fuel C. 1",57& 1",57&.2" .2" 3(, 3(, 17.27 17.27 (air 3( 3(fuel '. "5,"57 "5,"57.1$ .1$ 3(, 3(, 12.5" 12.5" ( ( air 3( 3(fuel $7. 8periment 8periment revealed revealed that that the calorific calorific value of an oil fuel b+ means of a bomb calorimeter calorimeter,, the mass of a sample fuel was 0.75 (ram, the mass of water surroundin( the bomb was 1. ( with some water in the fittin( 0."7 (, and the temperature rises b+ $.$ PC. Considerin( that the specific heat of water is ".2 3(=>, compute the calorific value of this oil in @3(. Answer: A A. "1,# "1,#"# "#.& .& 3 3( ( %. $5,$ $5,$"5 "5.2 .2 3 3(( C. "7," "7,"57 57.2 .2$$ 3 3(( '. $1,& $1,&7 7." ."55 3 3(( $. A fuel consis consists ts of "< carbon, carbon, 1$< h+dro(e h+dro(en, n, and the remain remainder der incombu incombusti stible ble solid solid matter matter.. Calculate the calorific value of the theoretical mass air reuired per ( of fuel and the mass anal+sis of the flue (as if 22 ( of air are supplied per ( of fuel burned. Answer: A A. "&,7#5 "&,7#5.$ .$ 3(, 3(, 1".0& 1".0& ( ( air 3( 3(fuel %. "5,77 "5,77.7 .7 3(, 3(, 15.0& 15.0& (air 3( 3(fuel C. $",57& $",57&.7 .7 3(, 3(, 1".75 1".75 (air 3( 3(fuel '. "5,5&7 "5,5&7.7 .7 3(, 3(, 15.&7 15.&7 ( ( air 3( 3(fuel $#. A fuel oil has the follo followin win(( conten contents9 ts9 5.$5< 5.$5< carbon, carbon, 11.#< 11.#< h+dro( h+dro(en, en, 1.&< o8+(en, o8+(en, and 1< impurities. Calculate the percenta(e C 2 in the flue (as for complete combustion. Answer: A A. 20.#"< %. $0.#"< C. $5.5< '. 17.5&< DIESEL POWER PLANT
1.
A si8 si8 c+linder c+linder,, four stroe stroe diesel diesel en(in en(inee with 7& 7& mm bore 8 # # stroe stroe was run run in the labora laborator+ tor+ at 2000 rpm, when it was found that the en(ine torue was 15$.5 4=m when one c+linder was out. /he en(ine consumed 12.2 ( of fuel per hour with a heatin( value of 5",120 3( of air at 15.& PC. 'etermine the indicated power. power. Answer: B A. $2.1 ) %. $." ) C. 2$.$ ) '. ".$ )
2.
A sin(le sin(le=ac =actin tin(, (, four c+lin c+linder der,, " stroe stroe c+cle c+cle diesel diesel en(ine en(ine with with a bore bore to stroe stroe of 21.5# 21.5# cm 8 27.#" cm, operatin( at 275 rpm, consumes .1# (3hr of fuel whose heatin( value is "$,#&1." 3(. /he load on the brae arm, which is #$.# cm is 11$." (. )hat is the brae arm mean effective pressure* Answer: C A. "12.2 12.200 !a %. 12".17 .17 ! !a C. $1#.#5 .#5 ! !a '. &"5.5 "5.5$$ !a
$.
A superc superchar( har(ed ed si8 c+lind c+linder, er, four four stroe stroe c+cle c+cle diesel diesel en(ine en(ine of 10." cm cm bore and 12.7 12.7 cm stroe stroe has a compression ratio of 15. )hen it is tested on a d+namometer with a 5$.$" cm arm at 2500 rpm, the scale reads 1.&5 (, 2.& ( of fuel of "5,22.20 3( heatin( value are burned durin( a & min. test and air metered to the c+linders at the rate of 0.12 (3s. Find the brae thermal efficienc+. Answer: C A. 0.$27 %. 0.$&7 C. 0.$07 '. 0.$57
".
?n a test labora laborator tor++, it was found found out that that of the 0 %hp %hp develop developed ed b+ an en(ine en(ine test, test, "5 -p are are absorbed b+ the coolin( water that is pumped throu(h the water acet and the radiator. /he water enters the top of the radiator at 200 PF. At that temperature, enthalp+ of the water is 1&.$07 %tu3lbm. )ater leaves the bottom of the radiator at 1#0 PF and with an enthalp+ of 15.0$ %tu3lb m. )hat is the water flow rate for a stead+= state condition* Answer: C A. 25 (al3 (al3mi minn %. 20 (a (al3min C. 2$ (a (al3min '. 2" (al3 (al3mi minn
5.
A certai certainn diesel diesel en(ine en(ine with with the followi followin( n( specif specifica icatio tions, ns, c+linde c+linderr, "00 mm 8 &00 mm, four stroe c+cle has a fuel consumption of 0.&0 lbs3hp=hr based on 1#,100 %tu3lb. n(ine speed is 20 rpm with an indicated mean effective pressure of 1$0 psi. ?f the water acet carries awa+ an estimated 25< of the heat supplied, find its capacit+ :I!@; reuired if the allowable rise is "0 PF. Answer: A
A. %. C. '. &.
2"1.# I!@ 2$&.5 I!@ 2"#.1 I!@ 2&.7 I!@
A 2000 2000 ) diesel diesel en(ine en(ine unit unit uses 1 bbl bbl oil per per 525 w=hr w=hr produced. produced. il il is 25 PA!?. PA!?. fficien fficienc+ c+ of (enerator is #$<, mechanical efficienc+ of en(ine is 0<. )hat is the thermal efficienc+ of the en(ine based on indicated power* Answer: A A. $1.&#< %. 2#."7< C. $#.&< '. $5.&<
7.
Find Find the powe powerr which which a 2.5 @) @) natur natural al (as (as en(ine en(ine can can devel develop oped ed at an alt altitu itude de of 1#1 1#1.2 .2 m tain( into consideration that the pressure chan(e alone. Answer: A A. 1.#57 @) @) %. 1.5#7 @) C. 1.7#5 @) '. 1.57# @) @)
.
A $7$ $7$ ) :500 :500 -p; -p; internal internal combus combustion tion en(ine en(ine has has a brae brae mean effecti effective ve pressure pressure of of 551.5 !a !a at full load. )hat is the friction power if mechanical efficienc+ is 5<* Answer: A A. .2$ -p %. 77.2$ -p C. ##.2" -p '. &&.2" -p
#.
A d+nam d+namome ometer ter test test was done done for one hour hour at stead+ stead+ load load on a & c+linde c+linderr diesel diesel en(ine en(ine.. ?t was found to use "2 ( of fuel havin( R h "2,000 3(. C+linder is 22. cm 8 27 cm, " c+cle t+pe. 6peed, 6peed, 550 rpm and d+namom d+namomete eterr toru toruee at 27,000 27,000 (=cm. (=cm. 'etermi 'etermine ne the brae brae therma thermall efficienc+. Answer: A A. $1.15< %. 2#.1&< C. $2.$&< '. $5.52<
10. A four=stro four=stroe, e, c+linder c+linder diesel en(ine en(ine with bore and stroe stroe of # inches and 12 inches respectiv respectivel+ el+ and speed of #50 rpm has a brae mean effective pressure of 1&" psi. /he specific fuel consumption is 0.$# lb3bhp=hr and the fuel heatin( value is 1,500 %tu3lb. 'etermine the thermal efficienc+. Answer: B A. $2.57< %. $5.27< C. 57.$5< '. "5.57< 11. 11. A four=st four=stroe roe $#" mm bore and 5$" 5$" mm stroe sin(le sin(le actin( actin( diesel en(ine en(ine with with four c+linder c+linder is (uaranteed to deliver $50 %-p at $00 rpm. /he en(ine consumed &&. (3hr of fuel with a heatin( value of "",251 3(. Calculate the indicated mean effective pressure in !a if mechanical efficienc+ is #<. Answer: A A. "51 !a %. "75 !a C. "#0 !a '. "25 !a 12. A $05 $05 mm 8 "57 mm four stroe sin(le sin(le actin( actin( diesel diesel en(ine en(ine is rated at 150 ) at 2&0 rpm. rpm. Fuel consumption at rated load is 0.2& (3)=hr with a heatin( value of "$,#12 3(. Calculate the brae thermal efficienc+. efficienc+. Answer: A A. $1.&$< %. "1.&$< C. 21.&$< '. $5.&$<
1$. A four four c+linder c+linder,, " stroe stroe c+cle, c+cle, 20 cm 8 25 cm 8 550 rpm diesel diesel en(ine en(ine has a mean mean effectiv effectivee pressure of 150 psi. Calculate Calculate the brae power in ) if en(ine efficienc+ efficienc+ is <. Answer: A A. 1$1 ) %. 1$ ) C. 1"1 ) '. 1" ) 1". A four four stroe, direct inection inection diesel en(ine en(ine of " in. bore bore 8 ".5 in. stroe develops develops "5 -p at full load and -p when runnin( at idlin( load. n(ine speed is 2,200 rpm. )hat is the mechanical efficienc+* Answer: A A. 5< %. < C. 77< '. 7"< 15. A 500 ) diesel diesel has a heat rate of 12,000 12,000 3w=hr 3w=hr.. the compression compression ratio ratio is 1&91, cut=off cut=off ratio ratio of 2.$. Assume 1.$2. Calculate the en(ine efficienc+ based on the output of 500 ). ). Answer: A A. 57.77< %. 57.7< C. "7.77< '. $7.&7< 1&. ?f the mean effectiv effectivee pressure pressure of a diesel en(ine en(ine is 500 !a and the mechani mechanical cal efficienc efficienc++ is 5<, what is the indicated mean effective pressure* Answer: A A. 5.2 .2"" !a %. 52". . ! !a C. &.2" .2" ! !a '. &2". 2". !a 17. /he brae brae thermal efficie efficienc+ nc+ of a 1 @) diesel diesel electric electric plant is $&<. $&<. Find the heat heat (enerated (enerated b+ fuel in ) if the (enerator efficienc+ is #<. Answer: A A. $,121 ,121.1 .100 ) ) %. $,52 ,52.& .&"" ) C. ",121 ,121.1 .100 ) '. ",52 ,52.& .&"" ) ) 1. A 500 ) diesel diesel en(ine en(ine develops develops torue torue of 2 4=m, 4=m, /he en(ine en(ine drives drives an altern alternati atin( n( current current (enerator with poles producin( current &0 -L. )hat is the speed ratio of speed reduction (ear* Answer: A
A. %. C. '.
2.&91 $.&91 1.&91 ".&91
1#. A diesel diesel en(ine is operatin( on a " stroe c+cle c+cle has a heat heat rate of 000 %tu3-p=hr. %tu3-p=hr. the compression ratio is 1$, cut=off ratio is 2 and 1.$2. Find the brae en(ine efficienc+. efficienc+. Answer: A A. &$."#< %. &".$#< C. &#."$< '. "&.#$<
20. )hat )hat is the mechanic mechanical al efficie efficienc+ nc+ of a 0.5 @) diesel diesel en(ine en(ine if the the fricti friction on power power is 70 ). ). Answer: A
A. %. C. '.
7.72< ".55< #.&1< .2"<
21. Ias is e8panded e8panded in in an en(ine en(ine c+linder c+linder followi followin( n( the law law ! n C where the value of n is 1.$. /he initial pressure is 2,250 !a and the final pressure is 210 !a. ?f the volume at the end of e8pansion is 0.75 m$, calculate the volume at the be(innin( of e8pansion. Answer: A A. 0.10## m$ %. 0.0## m$ C. 0.#01# m$ '. 0.##10 m$
GAS TURBINE PLANT
1.
A (as turbi turbine ne wori worin( n( on air air stan standa dard rd %ra+to %ra+tonn c+cl c+clee has has air air ente enterr into into the compre compress ssor or at atmospheric condition and 22 PC. /he pressure ratio is # and the ma8imum temperature in the c+cle is 1077 PC. Compute for the c+cle efficienc+ per ( of air in percent. Answer: A A. "".5< %. "$.#2< C. "1.&5< '. "2.&2<
2.
?n a (as (as turbin turbinee unit unit,, air air ente enters rs the comb combus usti tion on chamb chamber er at 550 !a, !a, 227 227 PC and and "$ m3s. m3s. /he /he products of combustion leave the combustor at 511 !a, 100" PC nd 1"0 m3s. Jiuid fuel enters with heatin( value of "$,000 3(. For fuel=air ratio of 0.022#, what is the combustor efficienc+ of the unit in percent* Answer: C A. &"< %. #2< C. 7< '. 102<
$.
Air Air enters enters the comb combus usti tion on chamb chamber er of a (as (as turbin turbinee unit at 550 550 !a, 227 227 PC and and "$ m3s. m3s. /he /he products of combustion leave the combustor at 517 !a, 1007 PC nd 1"0 m3s. Jiuid fuel enters with heatin( value of "$,000 3(. /he combustor efficienc+ is #5<. )hat is the air=fuel ratio* 4ote9 !roperties of air9 /:>; h:3(; 500 50$.02 120 1$72.25. Answer: D A. "7.$# %. $2.25
C. 5&.#$ '. "".#5 ".
5.
Air enters enters the the compresso compressorr of a (as turbine turbine at 100 100 !a and and $00 > with with a volume volume flow rate of 5 m $3s. /he compressor pressure ratio is 10 and its isentropic efficienc+ is 5<. At the inlet to the turbine, the pressure is #50 !a and the temperature is 1"00 >. /he turbine has an isentropic efficienc+ of < and the e8it pressure is 100 !a. n the basis of an air=standard anal+sis, what is the thermal efficienc+ of the c+cle in percent* Answer: C A. "2.0& %. &0.20 C. $1.# '. 25.15 )hat is is the therma thermall efficien efficienc+ c+ of an air=stan air=standard dard %ra+to %ra+tonn c+cle c+cle if the pressure pressure ratio ratio is 10* Answer: A
A. %. C. '.
".21< 50.1&< "5.$&< "2.""<
&.
?n a simple simple (as (as turbine turbine plant plant worin worin(( on the ideal ideal constant constant pressu pressure re c+cle, c+cle, air is taen taen into the compressor at 1 bar, 1& PC and delivered at 5." bar. ?f the temperature at turbine inlet is 700 PC. Calculate the ideal thermal efficienc+. /ae 1.". Answer: A A. $.2$< %. "2.&1< C. "5.&&< '. $5.$<
7.
Air Air is drawn drawn into into a (as (as turb turbin inee wor worin in(( on the the cons consta tannt pres pressu sure re c+cle c+cle at 1 bar bar 21 PC and and compressed to 5.77 bar. /he temperature at the end of heat suppl+ is &0 PC. /ain( /ain( e8pansion and compression to be adiabatic where C v 0.71 3(=>, C p 10.55 3(=>, calculate the heat ener(+ supplied per ( at constant pressure. Answer: A A. "72 3( %. $# 3( C. 501 3( '. "# 3(
.
)hat )hat is the thermal thermal effic efficien ienc+ c+ of an air=sta air=standa ndard rd %ra+ton %ra+ton c+cle c+cle if the air air enters enters and leave leavess the turbine at 1000 > and 550 > respectivel+* Answer: B A. "0.7"< %. "".##< C. 50.$< '. 5".&<
#.
/here /here are reui reuired red 2200 2200 ) net net from a (as turbin turbinee unit for for pumpin( pumpin( of crude crude oil. oil. Air Air enters enters the the compressor section at 100 !a, 20 >, the pressure ratio r p p 10. /he turbine sections receives the hot (ases at 1,100 >. Assume the closed %ra+ton c+cle and determine the reuired air flow. Answer: C
A. 7.#1 .#1 ( (3s %. 7.1& .1& (3s
C. .11 .11 (3s '. .#1 .#1 ( (3s 10. ?n an air=standa air=standard rd %ra+ton %ra+ton c+cle, the compressor compressor receives receives air at 101.$25 101.$25 !a, 21 PC and it leaves at &00 !a at the rate of " (3s. 'etermine the turbine wor if the temperature of the air enterin( the turbine is 1000 PC. Answer: C A. $000 ) %. 2701 ) C. 202 ) '. $500 ) 11. 11. /he net power output output of an air=standard air=standard %ra+ton %ra+ton c+cle is 200 ). ). Air enters enters the compressor compressor at $2 PC and leaves the hi(h=temperature heat e8chan(er at 00 PC. )hat is the mass flow rate of air if it leaves the turbine at $50 PC* Answer: D A. 0.57 .57 ( (3s %. 0.&7 .&7 (3s C. 0.77 .77 (3s '. 0.7 .7 ( (3s 12. /he compresso compressorr inlet air temperatu temperature re in a (as turbine plant plant is ## PC. Calculate Calculate the compressor compressor air e8it temperature if it reuires "00 3( of wor. Answer: A A. "## PC %. "00 PC C. 500 PC '. 5## PC 1$. ?n an air=standard air=standard %ra+ton %ra+ton c+cle air enters the compressor at 101.$25 !a and and 27 PC. 'etermine the net wor if the ma8imum temperature is 1000 PC and the pressure ratio is #. Answer: C A. "5&. "5&. 3 3(( %. "21.5 21.5&& 3 3( C. $$1." $1."77 3 3( '. $01. $01.7" 7" 3 3(( 1". )hat is the efficienc+ efficienc+ of the compressor compressor in a (as turbine turbine plant if the compressor compressor power is $00 $00 ). ). !ower input is "00 ). Answer: A A. 75< %. 0< C. 5< '. 70< 15. /he intae intae of the compresso compressorr of an air=standar air=standardd %ra+ton %ra+ton c+cle is $5,000 $5,000 ft $3min at 1" psia and #5 PF. /he compression ratio is " and the temperature at the turbine inlet is 1500 PF. /he e8it pressure of the turbine is 1" psia. 'etermine the mean effective pressure. Answer: A A. 25.0& ps psi %. 2.05psi C. $5.0& psi '. $.05 ps psi 1&. Calculate Calculate the the the wor done done per ( of (as e8pandin e8pandin(( from &.$$ ( abs abs to 1.05 (3cm (3cm 2 abs. in a (as turbine of 2< internal efficienc+. efficienc+. ?nitial temperature, 750 PCD 1.$", @ 2#. Answer: A
A. %. C. '.
$"# 3( "25 3( 2"# 3( 525 3(
17. >erosene >erosene is the the fuel of a (as (as turbine turbine plant9 plant9 fuel=air fuel=air ratio, ratio, m f 0.012, /$ #72 >, pressure ratio, r p p ".5, e8haust to atmosphere. Find the available ener(+ in > per ( air flow. Assume 1.$" and C p 1.1$. Answer: A A. $52. $52.&" &" 3 3(( %. "52.& 52.&"" 3 3( C. 252.& 52.&"" 3 3( '. 552. 552.&" &" 3 3(( 1. 1. An ideal ideal (as (as turb turbin inee oper operat ates es with a pres pressu sure re rati ratioo of 10 and and the the ener ener(+ (+ input input in the hi(h hi(h temperature heat e8chan(er is $00 ). Calculate the air flow rate for a temperature limits of $0 PC and 1200 PC. Answer: B A. 0.25 .25 ( (3s %. 0.$" .$" (3s C. 0."1 ."1 (3s '. 0.51 .51 ( (3s 1#. !roducts !roducts of combusti combustion on with of 1.$5, 1.$5, 55& >, molecular molecular wei(ht wei(ht @ 2#, are movin( within within an 2 e8haust pipe at 17" m3sD 1.12 (3cm abs. static pressure. Find the total pressure and temperature. Answer: C
A. %. C. '.
1.&1 .&1 (3c (3cm2, 50 > 1.&1 .&1 (3m2, 570 > 1.1$ .1$ ( (3cm2, 570 > 1.1$ .1$ (3c (3cm2, 50 >
20. ?n an air Gstandard Gstandard %ra+ton %ra+ton c+cle the inlet inlet temperatu temperature re and pressures pressures are 20 ºC and 101.$25 101.$25 !a. /he turbine inlet conditions are 1200 !a and #00 ºC. 'etermine the air flow rate if the turbine produces 12 @). @). Answer: B A. 21."1 1."1 (3s (3s %. 20.20 ( (3s C. 1#.25 ( (3s '. 1.10 .10 (3s (3s 21. A (as turbine turbine power plant plant operatin( operatin( on the %ra+ton %ra+ton c+cle delivers delivers 15 @) to a standb+ standb+ electric electric (enerator. )hat is the mass flow rate and the volume flow rate of air if the minimum and ma8imum pressures are 100 !a and 500 !a respectivel+, and temperatures of 20 ºC and 1000 ºC. Answer: A
A. %. C. '.
$1.# $1.#77 (3 (3s, s, 2&. 2&. m$3s $&.# $&.# (3 (3s, s, 2.# 2.### m$3s "1.# "1.#77 (3 (3s, s, 2&. 2&. m$3s "&.# "&.# (3 (3s, s, 2. 2.## ## m$3s STEAM POWER PLANT
1.
?n a Eanine Eanine c+cle c+cle,, steam steam enters enters the the turbine turbine at 2.5 2.5 @!a and and condens condenser er of 50 !a. !a. )hat )hat is the thermal efficienc+ of the c+cle*
6team !roperties9 at 2.5 @!a, h ( 20$.1 3(, 6 ( &.2575 3(=> and at 50 !a, 6 f 1.0#10 $ 3(=>, hf $"0."# 3(, h f( 2$05." 3(, v f 0.0010$00 m 3(. Answer: A A. 25.55< %. 2.7< C. $0.12< '. $1.7#< 2.
A superh superheat eat steam steam Eanine Eanine c+cle c+cle has turbi turbine ne inlet inlet conditio conditions ns of 17.5 17.5 @!a and 5$0 5$0 ºC e8pands e8pands in in a turbine to 0.007 @!a. /he turbine and pump pol+tropic efficiencies are 0.# and 0.7 respectivel+. !ressure losses between pump and turbine inlet are 1.5 @!a. )hat should be the pump wor in 3(* Answer: A A. 27.1$ 7.1$ 3 3(( %. 2#.7 #.7 3 3(( C. $2."7 2."7 3 3(( '. $$.25 $.25 3 3((
$.
6team enters enters the the superheat superheater er of a boiler boiler at a pressu pressure re of 25 bar bar and dr+ness dr+ness of 0.# and and leaves leaves at the the same pressure at a temperature of $70 ºC. Calculate the heat ener(+ supplied per ( os steam supplied in the superheater. 6team properties9 at 25 bar and $70 $70 ºC, h $171. 3(, at 25 bar, bar, h f #&2.11 3(, h f( 1"1.0 3(. Answer: A A. "05. "05.51 51 3 3(( %. 50".1 0".155 3 3( C. 15".1 5".155 3 3( '. 2"5. 2"5.25 25 3 3((
".
A bac bac pressure pressure steam steam turbine turbine of of 100,000 100,000 ) serves serves as as a prime mover mover in a co(ene co(eneratio rationn s+stem. s+stem. /he boiler admits the return water at a temperature of && ºC and produces the steam at &.5 @!a and "55 ºC. 6team then enters a bac pressure turbine and e8pands to the pressure of the process, which is 0.52 @!a. Assumin( a boiler efficienc+ of 0< and ne(lectin( the effect of pumpin( and the pressure drops at various location, what is the incremental heat rate for electric* /he followin( enthalpies have been found9 turbine entrance $$0&. 3(, e8it 2700. 3(D boiler entrance 27&.2$ 3(, e8it $$0&. 3(. Answer: A A. 22,5 22,50" 0".2 .2$$ 3 3(( %. 52,2 52,2"" "".$ .$22 3 3(( C. 12," 12,"$5 $5.7 .722 3 3(( '. $2,2 $2,2$" $". .22 3 3((
5.
6team 6team e8pand e8pandss adiabat adiabatica icall+ ll+ in a turbin turbinee from 2000 2000 pa, pa, "00 ºC to "00 !a, !a, 250 ºC. )hat )hat is the effectiveness of the process in percent assumin( an atmospheric temperature of 15 ºC. 4e(lect chan(es in inetic and potential ener(+. 6team properties9 At 2000 !a and "00 ºC "00 !a and 250 ºC h $2"7.& 3( h 2#&".2 3( 6 7.1271 3( => 6 7.$7# 3(=> . Answer: A A. 7#.&2< %. ".52< C. 2."5<
'. 7".57< &.
?n an open feed feedwa wate terr heat heater er for a stea steam m powe powerr plan plant, t, satur saturat ated ed steam steam at 7 bar bar is mi8ed mi8ed with with subcooled liuid at 7 bar and 25 ºC. ust enou(h steam is supplied to ensure that the mi8ed steam leavin( the heater will be saturated liuid at 7 bar when heater efficienc+ is #0<. Calculate the mass flow rate of subcooled liuid if steam flow rate is 0.&5 ( per second. 6team properties9 At 7 bar, saturated vapor At 7 bar, saturated liuid h( 27&$.5 3( h f &07.22 3( At 7 bar, and 25 ºC hf 105.5 3(. Answer: A A. 2.725 %. $.$5& C. 2.2& '. $.#"
7.
A steam steam plant plant operate operatess with an initial initial pressur pressuree of 1.70 @!a @!a and $70 ºC ºC temperatur temperaturee and e8haust e8haust to a heatin( s+stem at 0.17 @!a. /he condensate from the heatin( s+stem is returned to the boiler at &5.5 ºC and the heatin( s+stem utiliLes from its intended purpose #0< of the ener(+ transferred from the steam it receives. /he turbine efficienc+ is 70<. ?f the boiler efficienc+ is 0<, what is the co(eneration efficienc+ of the s+stem in percent. 4e(lect pumpwor. 6team !roperties9 At 1.7 @!a, and $70 ºC At 1.7 @!a h $77.1 3( h f "$.20 3( 6 7.101 3(=> h f( 221&.0 3( At &5 ºC 6f 1."752 3(=> hf 27".1" 3( 6 f( 5.70&2 3(=>. Answer: D A. 7 %. 102.1" C. #1.2" '. &#
.
?n a co(ener co(enerati ation on plant plant,, steam steam enters enters the turb turbin inee at " @!a and "00 ºC. ºC. ne fourth fourth of the the steam steam is e8tracted from the turbine at &00 !a pressure for process heatin(. /he remainin( steam continues to e8pand to 10 pa. /he e8tracted steam is then condensed and mi8ed with feedwater at constant pressure and the mi8ture is pumped to the boiler pressure of " @!a. /he mass flow rate of the steam throu(h the boiler is $0 (3s. 'isre(ardin( an+ pressure drops and heat losses in the pipin(, and assumin( the turbine and pump to be isentropic, how much process heat is reuired in )* 6team !roperties9 At " @!a, and "00 ºC At &00 !a h $21$.& 3( h f &70.5& 3( 6 &.7� 3(=> h f( 20&.$ 3( 6f 1.#$12 3(=> 6f( ".2 3(=>. Answer: A A. 15,&"&. %. 2,"&.2 C. $,57.5 '. 1,02 ,02&.#0
#.
A 2$.5 2$.5 ( of steam steam per per second second at 5 @!a and "00 "00 ºC is produc produced ed b+ a stea steam m (enera (enerato torr. /he feedwater enters the economiLer at 1"5 ºC and leaves at 205 ºC. /he steam leaves the boiler drum with a ualit+ of #<. /he unit consumes 2.75 ( of coal per second as received havin( a heatin( value of 25,102 3(. )hat would be the over=all efficienc+ of the unit in percent* 6team !roperties9 At 5 @!a and "00 ºC At 205 ºC h $1#5.7 3( h f 75.0" 3( At 5 @!a At 1"5 ºC hf 115".2$ 3( h f &10.&$ 3( hf( 1&"0.1 3(. Answer: C A. &5 %. #5 C. '. 7
10. A coal fired fired power plant plant has a turbine=( turbine=(enera enerator tor rated at 1000 @) (ross. (ross. /he plant reuired reuired about about #< of this power for its internal operations. ?t uses #00 tons of coal per da+. /he coal has heatin( value of &,$.# Cal3(, and the steam (enerator efficienc+ is &<. )hat is the net station efficienc+ of the plant in percent* Answer: A A. $$.07< %. "0.01< C. $&.7"< '. $0.12< 11. 11. 6team enters enters the turbine turbine of a co(enera co(eneration tion plant plant at 7.0 @!a and 500 500 ºC. 6team at a flow rate rate of 7.& (3s is e8tracted from the turbine at &00 !a pressure for process heatin(. /he remainin( steam continues to e8pand to 10 !a. /he recovered condensates are pumped bac to the boiler. boiler. /he mass flow rate of steam that enters the turbine turbine is $0 (3s. (3s. Calculate the co(eneratio co(enerationn efficienc+ efficienc+ in percent. At 7 @!a, and 500 ºC At &00 !a h $"10.$ 3( h f &70.5& 3( 6 &.7#75 3(=> hf( 20&.$ 3( At 10 pa
6 f 1.#$12 3(=>
hf 1#1.$ 3( hf( 2$#2. 3( 6f 0.&"#$ 3(=> 6f( 7.500# 3(=. Answer: D A. %. C. '.
&0 50 &5 55
6 f( ".223(=>. ".223(=>.
12. A &0 @) turbine (enerator (enerator runnin( at $&00 rpm receives receives steam at ".0 @!a and "50 ºC with with a bac pressure of 10 !a. n(ine efficienc+ is 7< and the combined mechanical and electrical efficienc+ is #5< . )hat would be the e8haust enthalp+ of the steam in 3(* Answer: B A. 2,1 2,12" 2".2 .200 3 3(( %. 2,"0 2,"00. 0.12 12 3 3(( C. 20," 20,"$2 $2.1 .100 3 3(( '. $0,1 $0,101 01.1 .155 3 3(( 1$. 6team 6team enters enters a throt throttli tlin( n( calorime calorimeter ter at a press pressure ure of 1.0$ 1.0$ @!a. @!a. /he calorim calorimete eterr downst downstrea ream m pressure and temperature are respectivel+ 0.100 @!a and 125 ºC. what is the percenta(e moisture of the suppl+ steam* !roperties of 6team9 !1 1.0$ @!a hf( 2010.7 3( h ( 277#.25 3( 4ote9 at 0.100 @!a and 125 ºC, h 272&.& 3(. Answer: A A. 2.&2 %. 5.21 C. $.15 '. 1.# 1". A drum drum containin( containin( steam steam with 2.5 m in diameter diameter is 7.5 m lon(. f the total total volume 13$ 13$ contains contains saturated steam at 00 !a and the other 23$ contains saturated water.if this tan should e8plode, how much water would evaporate* Consider the process to be of constant enthalp+. enthalp+. Answer: A A. 2,#" 2,#". .111 ( %. 2,"2" ,"2".& .&22 ( C. 2,&51 ,&51.2 .2"" ( '. 2,12$ ,12$.7 .7&& ( ( 15. A %atan(as %atan(as base industrial industrial compan+ compan+ operates operates a steam=pow steam=power er plant with reheat reheat and re(eneration. re(eneration. /he steam enters a turbine at $00 bar and #00 > and e8pands to 1 bar. 6team leaves the first sta(e at $0 bar and part of it enterin( a closed heater while the rest reheated to 00 >. %oth section of the turbine have adiabatic efficienc+ of #$<. A condensate pump e8ist between the main condenser and the heater. Another pump lies between the heater and condensate outlet line from the heater :condensed e8tracted steam;. Compute for the e8tracted fraction of the total mass flow to the heater. Answer: A A. 0.2$" %. 0.5"$ C. 0.7&5 '. 0."5 1&. ?n a Eanine c+cle, c+cle, saturated saturated liuid water water at 1 bar is compressed compressed isentrop isentropicall icall++ to 150 bar. First First b+ heatin( in a boiler and then b+ superheatin( at constant pressure of 150 bar, water substance is brou(ht to 750 >. after adiabatic reversible e8pansion in a turbine to 1 bar, it is then cooled in a condenser to a saturated liuid. -ow much wor is (enerated in the turbine* Answer: B A. #&7.# &7.# 3 3(( %. $#7&. #7&.## 3 3( C. 7#&.# #&.# 3 3(( '. 7&#.# &#.# 3 3(( 17. A reheat reheat steam has 1$,50 1$,50 !a throttle throttle pressure pressure at the turbine turbine inlet and 200 200 !a reheat reheat pressure, pressure, the throttle and reheat temperature of the steam is 5"0 PC, condenser pressure is $." !a, en(ine efficienc+ of hi(h pressure and low pressure is 75<. Find the c+cle thermal efficienc+. efficienc+. Answer: A A. $"."&<
%. $5.5&< C. $&.&&< '. $7.7&< 1. A simple steam en(ine en(ine plant has boiler feedwater at #5.& PC. 6team is is supplied to to the en(ine at 7.0$ 2 (3cm , #7< dr+. Atmospheric e8haust. 6team rate #.$ ( per ihp=hr, e m 7<. Ienerator of #1.5< efficienc+ is directl+ connected to the en(ine. 'etermine the Eanine c+cle efficienc+. Answer: C
A. %. C. '.
#.< 12."7< 11.&$< 1.055<
1#. A 75 ) turbine turbine (enerat (enerator or has a steam steam of 12.7 12.7 (3) (3)=hr. =hr. 6team at 12.$ (3cm (3cm 2 (au(e 55.& PC superheat. 8haust 50. mm -( abs. find the combined thermal efficienc+ of a simple vapor c+cle incorporatin( this unit. Answer: D A. #.&7< %. 12.15< C. 11.&"< '. 10.25< 20. Ab thermal thermal power plant plant (enerates (enerates "000 ) and "00 "00 ) for au8iliaries au8iliaries.. 'etermine 'etermine the net thermal thermal efficienc+ if the heat (enerated b+ fuel is 15000 ). Answer: A A. 2"< %. 2&< C. 2< '. $0< 21. A steam steam (eneratin( (eneratin( plant plant has 20 @) turbo=( turbo=(enera enerators tors.. 6team is supplied supplied at 1.7 @!a and $20 PC. 8haust is at 0.00& @!a. 'ail+ avera(e load factor is 0<. /he steam (eneratin( units operate at 70< efficienc+ when usin( buner fuel havin( a heatin( value of $1,150 3( and an avera(e steam rate of 5 ( steam per )=hr. )=hr. Calculate the @tons of fuel reuired per 2" hours. Answer: A A. 51" 51".#" .#" @t @ton onss %. 527 527." ."#& #& @t @ton onss C. "1" "1".#" .#" @t @ton onss '. "2 "2."#& ."#& @t @ton onss 22. Find the the entrop+ entrop+ of wet steam steam of temperatu temperature re 1#5 PC and dr+nes dr+nesss 0.#0. 6team !roperties9 At 1#5 PC 6f 2.2" 3(=>, 6f( ".15 3(=>. Answer: A A. &.05 &.05 3 3(= (=> > %. 7.0" .0" 3 3(=> C. 5.2& 5.2& 3 3(= (=> > '. $.57 $.5755 3 3( (=> =>
2$.
sin sin( the the form formul ulaa 6 Cw
Csup ln
, where Cw mean specific heat of water, C sup
mean specific heat of superheated steam, / sat absolute saturation temperature, / absolute superheated steam temperature, calculate the entrop+ per ( of superheated steam at 15 bar :1.5 @!a; and $00 PC, tain( the mean specific heats of water and superheated steam as ".2" 3(=> and 2."$ 3(=> respectivel+. 6team !roperties9 At 15 bar :1.5@!a; /sat 1#.# 27$ "71.$ > hf( 1#"7 3( . Answer: A A. &.#1 &.#1#& #& 3 3( (=> => %. 5."# 5."#72 72 3 3(= (=> > C. ".57 ".57&# &# 3 3(= (=> > '. 5."& 5."&72 72 3 3( (=> =>
2". 'r+ saturated saturated steam steam at 5.5 bar :0.55 @!a; is e8panded e8panded isentropic isentropicall+ all+ to 0.2 bar, bar, find the dr+ness dr+ness fraction of the steam at the end of the e8pansion. 6team !roperties9 At 5.5 bar :0.55 @!a; At 0.20 bar :0.020 @!a; 6( &.7#0 3(=> 6f 0.$2 3(=> 6f( 7.075 3(=>. Answer: D A. 7".5< %. 7.5< C. ".22< '. 7".5"< 25. 6uperheate 6uperheatedd steam at 17 bar :1.7 :1.7 @!a; and $50 PC is e8pand e8panded ed in an en(ine en(ine and the final final pressure pressure is 1.7 bar :0.17 @!a;. ?f the e8pansion is isentropic, find the dr+ness fraction of the e8panded steam. 6team !roperties9 At 17 bar :1.7 @!a; and $50 PC At 1.7 bar :0.17 @!a; 6 7.0"" 3(=> 6f 1."75 3(=> 6f( 5.707 3(=>. Answer: A A. #7.5#< %. #.5"< C. #".5"< '. #$.5"< 2&. 6uperheate 6uperheatedd steam at a pressure pressure of 20 bar and temperature temperature $00 PC is e8panded e8panded isentropical isentropicall+ l+.. At what pressure will the steam be ust dr+ and saturated* Answer: A A. & bar %. bar C. 10 bar '. " bar 27. /wo boilers boilers of eual evapora evaporativ tivee capaci capacitie tiess (enera (enerate te steam steam at the the same same pressu pressure re of 15 bar :1.5 :1.5 @!a; to a common pipe line. ne boiler produces superheated steam at 150 PC and the other
produces wet steam. ?f the mi8ture is ust dr+ and saturated, find the dr+ness fraction of the wet steam from the second boiler. boiler. 6team !roperties9 At 15 bar :1.5 @!a;, 250 PC At 15 bar :1.5 @!a; h 2#25 3( hf "5 3( hf( 1#"7 3( h( 27#2 3(. Answer: A A. 0.#$15 %. 0."25 C. 0.71"2 '. 0.&57$
2. A 0.2 $ of steam at 7 bar :0.7 @!a; and 0.#5 dr+ is e8panded to a pressure of :".5 bar; 0."5 @!a. Calculate the dr+ness fraction of the e8panded steam if the e8pansion follows the law ! C. 6team !roperties9 At 7 bar :0.7 @!a; At ".5 bar :0."5 @!a; v( 0.272 m $3( v( 0."1$# m$3(. Answer: A A. 0.#7" %. 0."& C. 0.7&5 '. 0.&&7 2#. A closed closed s+stem consistin( of of 1 ( of superheated steam steam at 20 bar :2 @!a; and "00 PC is cooled at constant volume until the pressure is 12 bar :1.2 @!a;. Find the condition of the steam at the lower pressure. 6team !roperties9 At 20 bar :2 @!a; At 12 bar :1.2 @!a; - $2" 3( hf 7# 3( $ 0.1511 m 3( hf( 1#& 3( ( 0.1&$2 m$3(. Answer: B A. 0.25 %. 0.#25 C. 0.725 '. 0.&25 $0. /he turbine turbine wor and the pump pump wor in a Eanine c+cle c+cle are 1200 3( and and 20 3( respectiv respectivel+ el+.. )hat is the efficienc+ of the c+cle if the heat (enerated b+ the (enerstor is $000 3(* Answer: B A. $&.77< %. $#.$$< C. $5."5< '. $.$2< $1. ?n a Eanine Eanine c+cle, what is the entrance entrance pressure of the turbine turbine if the the condenser pressure is 105 !a and the pump wor is 20 3(. se densit+ of water enterin( the pump, #50 (3m $. Answer: C A. 17.#1& .#1& @! @!aa
%. 15.&0 .&01 @! @!a C. 1#.10 .105 @! @!a '. 1."$2 ."$2 @!a @!a
$2. 8haust 8haust steam steam from an en(ine passes passes into a condenser condenser at a pressure pressure of 0.12 bar and dr+ness dr+ness 0.. 0.. /he temperature of the condensate from the condenser is "0 PC. /he circulatin( water enters the condenser at 12 PC and leaves at 2# PC. Calculate the mass of circulatin( water per ( steam condensed. 6team !roperties9 6team at 0.12 bar :0.012 @!a; hf 207 3( hf( 2$$ 3( )ater !roperties9 )ater at "0 PC h 1&7.5 3(
)ater at 2# PC
)ater at 12 PC
h 121.5 3(
h 50." 3(. Answer:
C
A. %. C. '.
2&.71 ( ( 2.05 ( $0.0" ( $2.& ( (
$$. ?n an e8periment e8periment to determine determine the dr+ness dr+ness fraction fraction of sream, sream, a simple at a pressure pressure of 1.1 bar :0.11 :0.11 @!a; was blown into a vessel containin( 10 ( of water at 15 PC. /he final mass of water mass in the vessel was 10.75 ( and the final temperature is 55 PC. Find the dr+ness fraction of steam, tain( the water euivalent of the vessel as 0."5 (. 6team !roperties9 6team at 1.1 bar :0.11 @!a; -f "2# 3( -f( 2251 3( )ater !roperties9 !roperti es9
)ater at 55 PC
)ater at 15 PC
- 2$0.2 3( A. %. C. '.
h &2.# 3(. Answer: A 0.#"&# 0.#"5 0.#15& 0.7#7
$". /he differen difference ce in enthalp+ enthalp+ at the entrance entrance and e8it in the first and second second sta(e sta(e of a reheat reheat power plant are 500 3( and #00 3( respectivel+. 'etermine the plant c+cle efficienc+ if both sta(es has an efficienc+ of #0< and the heat added to the boiler is $500 3(. 4e(lect pump wor. Answer: A
A. %. C. '.
$&< $"< "0< "2<
$5. A throttl throttlin( in( calorim calorimete eterr was fitted fitted to pipe carr+in( carr+in( steam steam at 1.2 @!a on order order to measur measuree the dr+ness fraction. /he pressure in the calorimeter was 0.12 @!a and its temperature was 11& PC. /ain( the specific heat of the superheated steam in the calorimeter as 2.0 3(=>, find the dr+ness fraction of the main steam. 6team !roperties9 6team at 1.2 @!a 6team at 0.12 @!a -f 7# 3( tsat 10". PC -f( 1#& 3( h( 2&$ 3(. Answer: A A. 0.#&0$ %. 0.#&0 C. 0.4 '. 0.75&$ $&. A combined combined separatin( separatin( and throttli throttlin( n( calorimeter calorimeter was connected connected to a main steam pipe carr+in( carr+in( steam at 15 bar :1.5 @!a; and followin( data recorded9 @ass of water collected in a separator 0.55 ( @ass of condensate after throttlin( 10 ( !ressure of steam in throttlin( calorimeter 1.1 bar 0.11 @!a /emperature of steam in throttlin( calorimeter 111 PC /ain( the specific heat of the throttled superheated steam as 2.0 3(=>, find the dr+ness fraction of the main steam. 6/A@ !E!E/?69 At 15 bar :1.5 @!a;
At 1.1 bar :0.11 @!a;
hf "5 3(
tsat 102.$ PC
hf( 1#"7 3(
h( 2&0 3(. Answer: A A. 0.#01 %. 0.#5" C. 0.7#0
'. 0.#72 $7. A steam steam (enerator (enerator has an e8it enthalp+ enthalp+ of $500 3( 3( at the rate of 15 (3s. Calculate Calculate the heat lost lost between boiler outlet and turbine inlet if the enthalp+ available at the turbine inlet is $200 3(. Answer: A
A. %. C. '.
="500 ) =2500 ) =5700 ) =7&50 )
$. 'r+ satura saturated ted steam steam at a pressu pressure re of :2." bar; 0.2" @!a is tapped tapped off the inlet inlet branch branch of a low pressure turbine to suppl+ heatin( steam in a contact feed heater. /he temperature of the feedwater inlet to the heater is "2 PC and the outlet is ##.& PC. Find the percenta(e mass of steam tapped off. 6team !roperties9 6team at :2." bar; 0.2" @!a h( 2715 3( )ater !roperties )ater at "2 PC )ater at ##.& PC h 175. 3( h "17 3(. Answer: A A. #.5< %. 7.5< C. .5< '. 7.5< $#. /en percent of the mass of steam supplied supplied to an en(ine en(ine is bleed off at an intermediate sta(e sta(e and led to a surface feed heater. /he pressure of the steam to the heater is 2.# bar :0.2# @!a; and the drain from the heater passes as water to the hotwell. /he temperature of the condensate from the condenser is "0 PC and the temperature of the feedwater to the boilers is 100 PC. Calculate the dr+ness fraction of the steam supplied to the heater. heater. 6team !roperties hf 55& 3( hf( 21& 3( )ater properties )ater at "0 PC )ater at 100 PC h 1&7.5 3( h "1#.1 3(. Answer: A A. 0.#0# %. 0.70# C. 0.#0 '. 0."# "0. A turbine turbine in a Eanin Eaninee c+cle c+cle has an availa available ble enthal enthalp+ p+ of 1000 1000 3( 3(.. 'eterm 'etermine ine the net c+cle output if the mass flow rate is & (3s and the pump wor is 150 3(. Answer: D A. &. @) %. $.7 @) C. ".& @) '. 5.1 @)
"1. "1. 'uri 'urin( n( the proc proces esss of rais raisin in(( stea steam m in a boil boiler er,, when when the the pres pressu sure re was was 1.# 1.# bar bar (au( (au(ee the the temperature inside the boiler was 1$0 PC and when the pressure was &.25 bar (au(e :0.&25 @!a(; the temperature was 1&5 PC. ?f the volume of the steam space is constant at ".25 m $. Calculate the mass of steam. 6team !roperties 6team at 1$0 PC ! 2.7 bar ( 0.&&& (3m $. Answer: D A. $.$5& ( ( %. ".$5& ( C. 5.$5& ( '. &.$5& ( (
"2. A heat heat en(ine en(ine has the the followin followin(( specifica specification tions9 s9 !ower developed 50 ) Fuel %urned per hour $ ( -eatin( value of fuel 75,000 3( /emperature limits &27 PC and 27 PC. Answer: C A. Eealit+ %. Costl+ C. ?mpo ?mposssib sible '. Cheaper "$. A 50 @) thermal thermal plant plant has a thermal thermal efficienc+ efficienc+ of $2< based based on its combined combined output. output. ?f the plant operates continuousl+ :2" hr3da+;. -ow man+ tons of coal is burned per da+ at $0,000 3( to produce the desired output. output. /ae /ae boiler efficienc+ as 5< 5< and how man+ m $ per hr sea water :6I 1.05; is reuired the condenser if C pw ".2 3(=> and St w 10 PC. Answer: A A. 52#."1 52#."1 tons3 tons3da+ da+,, ,&7$." ,&7$."77 m $3da+ %. $21."5 $21."5 tons tons3da 3da++, 5,770. 5,770.57 57 m$3da+ C. "57.# "57.# tons tons3da 3da++, 7,#0. 7,#0.#7 #7 m$3da+ '. "7&.75 "7&.75 tons3 tons3da+ da+,, ",577.5 ",577.5"" m $3da+ "". A boiler boiler operates operates at 1.2" @!a abs abs and delivers delivers dr+ and saturate saturatedd steam, which which is e8panded e8panded to 100 !a atmospheric pressure in a steam en(ine havin( a steam rate of 12 ( per horsepower hr. /emperature of feedwater is #$ PC. Find the Eanine vapor c+cle efficienc+. efficienc+. Answer: A A. 1< %. 1#< C. 2"< '. $2< STEAM GENERATOR
1.
A steam steam boile boilerr on a test test (enerates (enerates 5,00 5,0000 lb of steam steam in a " hr period period.. /he avera( avera(ee steam steam pressure pressure is "00 psia, the avera(e steam temperature is 700 PF, and the avera(e temperature of the feed water supplied to the boiler is 20 PF. ?f the boiler efficienc+ for the period is 2.5< and if the coal has a heatin( values of 1$,50 %tu3lb as fired, find the avera(e amount of coal burned in short tons per hour. Answer: B A. #." #." shor shortt ttons ons per hour hour
%. 10.75 10.75 short short tons tons per hour hour C. 12.05 12.05 short short tons tons per hour hour '. 11."5 1."5 short short tons tons per per hour hour 2.
A boi boile lerr oper operat atin in(( at 11 11 (3c (3cm m 2 is reuired to (enerate a minimum of 50,000 (3hr of saturated steam. Feedwater enters the boiler at 0 PC. /he furnace is desi(ned to fire coal at an avera(e rate of ",00 (3hr and boiler efficienc+ is 5<. Compute the developed boiler horsepower. Answer: A A. $,"&2 ,"&2.5 .522 -p -p %. ",$5& ,$5&.7 .7 -p C. 5,2$" ,2$".7 .755 -p '. 2,5&0 ,5&0." ."55 -p -p
$.
A water water tube tube boile boilerr evapora evaporated ted 5.05 5.05 ( of water water per second second from from a feed water water temper temperatu ature re of 10"."" PC to steam at 12"1.1 !a and ualit+ of 0.#7D wei(ht of coal fuel per second 0.57 (D hi(her heatin( value of coal as fired, 11,00 %tu3lb. 'etermine the rate of absorption in 3s, the boiler horsepower, horsepower, and the efficienc+ of steam steam (eneratin( units. units. Answer: A A. 11,55 11,55 3(, 3(, 1,17 1,17 %o. -p, -p, 7$.7< 7$.7< %. 12,$"5 12,$"5 3 3(, (, 1,2$" 1,2$" %o. %o. -p, -p, ".$5< ".$5< C. 1",5&7 1",5&7 3 3(, (, 1,0"5 1,0"5 %o. %o. -p, -p, &7."5< &7."5< '. 10,275 10,275 3( 3(,, 1,"75% 1,"75%o. o. -p, -p, $.25< $.25<
".
A waste waste heat heat recover+ recover+ boiler boiler produces produces ". ". :dr+ saturat saturated; ed; steam steam from 10" PC PC feed water water.. /he boiler boiler receives ener(+ from 5 (3s of #5" PC dr+ air. After passin( throu(h the waste heat boiler, the temperature of the air has been reduced to $"$ PC. -ow much m uch steam in ( is produced per second* 4ote9 At ". @!a dr+ and saturated, saturated, h 27#&.0 3(. Answer: A A. 1.$ %. 0.#2 C. 2.1 '. $."
5.
A steam steam (ene (enera rati tin( n( plant plant cons consis isti tin( n( of a boil boiler er,, an econ econom omiL iLer er and and supe superr heat heater er (ene (enera rate tess superheated steam at the rate of 50 tons per hr. feedwater enters the boiler at 5 @!a and 120 PC. 6team leaves the superheater at ".5 @!a and $20 PC. if the coal used has a heatin( value of $0,000 3(, calculate the no. of tons of coal fired per hr for a (ross efficienc+ of 5<. Answer: A A. ". ".## ton tons3 s3hr hr %. 5.# 5.#77 tons tons3h 3hr r C. $.2& $.2&77 tons tons3h 3hr r '. 2.&7 2.&755 ton tons3 s3hr hr
&.
A water water tube tube boiler boiler has a capaci capacit+ t+ of 1000 1000 (3hr (3hr of steam. steam. /he /he factor factor of evapor evaporation ation is 1.$, boile boiler r 2 ratin( is 200<, boiler efficienc+ is &5<, heatin( surface area is 0.#1 m per %o. -p, and the heatin( value of fuel is 1,"00 Cal3(. /he total coal available in the buner is 50,000 (. 'etermine the no. of hours to consume the available fuel. Answer: A A. 5$.$ 5$.$&& hrs %. 70&.57 .57 hr hrs C. #7#."& ."& hr hrs '. 100.7 00.755 hrs
7.
/wo boiler boilerss are operatin operatin(( steadil+ steadil+ on #1,000 #1,000 ( of coal contai contained ned in a buner buner. ne is producin producin(( 15#1 ( of steam per hour at 1.2 factor of evaporation and an efficienc+ of &5< and another boiler produced 1$&" ( of steam per hour at 1.15 factor of evaporation and an efficienc+ of &0<. -ow man+ hours will the coal in the buner run the boilers if the heatin( value of coal is 7,5#0 Cal3(* Answer: A
A. %. C. '.
2$0. $0.00 hrs 20.5" .5" hr hrs $50.$5 .$5 hr hrs $00.5 00.5"" hrs
.
/he follow followin( in( coal has the followin( followin( ultimate ultimate anal+sis anal+sis b+ wei(h wei(ht9 t9 C 70.5< -2 ".5< 2 &.0< @oisture "< 6 $.0< Ash 11< 42 1.0< A stocer fired boiler of 175,000 (3hr steamin( capacit+ uses this coal as fuel. Calculate the volume of air in m $3hr with air at &0 PF and 1".7 psia pressure if boiler efficienc+ is 70<, e $0< and F 1.10. Answer: A A. 212,$ ,$0 m$3hr %. $"2,# ,#7 m$3hr C. 122,$" ,$"5 m$3hr '. 1$2,"5 ,"5& m$3hr
#.
Find Find the rated rated boile boilerr hors horsep epow ower er of a -.E./ -.E./.. boil boiler er &0 in. in. in diame diamete terr 1& ft lon( lon(,, and and havi havin( n( sevent+ and $ in. .'. tubes with 0.10# in. wall* Answer: A A. #5.0# 5.0# %o. %o. -p -p %. 7.0# .0# %o.%o.-pp C. #.0# #.0# %o. %o. -p -p '. #$.0# $.0# %o. %o. -p -p
10. )hat is the heatin( heatin( surface surface of a water water tube boiler if the euivalen euivalentt rated boiler boiler horsepower horsepower is 200* Answer: A
A. %. C. '. 11.
12 20& "50 1#
/he /he heati heatin( n( surf surfac acee area area of a fire fire tube tube boil boiler er is "00 "00 m 2. )hat is the euivalent rated boiler horsepower* Answer: A A. $&$.&" .&" -p -p %. "$5.72 .72 -p C. 25&.7 .7 -p '. 1$5.72 .72 -p -p
12. )hat )hat would would be the percent percenta(e a(e of the over=al over=alll effic efficien ienc+ c+ of a steam steam (enerat (enerator or obtaini obtainin( n( an evaporation euivalent to 10.#5 ( of water from and at 100 ºC per ( of coal containin( $",0&" 3( heatin( value* Answer: A A. 7$< %. 7"< C. 2< '. 70< 1$. For a (eneration (eneration of dr+ dr+ and saturated saturated steam at 1.0 @!a absolute, what what is the the percenta(e (ain in heat when the boiler feedwater is heated from $0 ºC to #0 ºC* Answer: C A. ."7< %. #.#7< C. #."7< '. 5."7< 1". )hat )hat is the the percent percent ratin( ratin( of a water tube tube boiler boiler if the heatin( heatin( surfac surfacee area is "00 m 2 and the developed boiler horsepower is 750* Answer: A A. 170.&2 .&25< %. 1"0.&7 .&75< C. 1$0.&2 .&25< '. 120.7& .7&5< 15. Coal with with a hi(her heatin( heatin( value value of &700 Cal3( Cal3( is consumed consumed at the rate of &00 (3hr (3hr in a steam (enerator with a rated boiler horsepower of 200. /he feedwater temperature is 2 ºC and steam (enerated is at 10.2 (3cm 2 abs. saturated condition. /he horsepower developed is euivalent to $05. )hat is the heatin( surface area* Answer: A A. 12 m2 %. 2$0 m2 C. 12$ m2 '. $2" m2 1&. %ased on probl problem em no. 15, calcula calculate te the rate of steam steam evaporat evaporated. ed. Answer: A A. ","2 ","2". ".& & (3 (3hr hr %. ",5&7 ,5&7 (3h (3hr r C. 5,57 5,57#. #.7 7 (3h (3hr r '. 5.&7 5.&7. ."5 "5 (3 (3hr hr 17. %ased on probl problem em no. 15, )hat )hat is the percent percent ratin( ratin( develop developed* ed* Answer: A A. 152.50 .50< %. 125."5< C. 2$".75< '. 1$".57 .57< 1. %ased on problem problem no. 15, 15, determine determine the A6@ A6@ evaporati evaporation on unit in %tu3hr %tu3hr.. Answer: A A. 10,5 10,5111.7& 1.7& %tu %tu3h 3hr r %. #,2$ #,2$". ".75 75 %tu %tu3h 3hr r C. 10,2 10,2111.57 1.57 %tu %tu3h 3hr r '. 12,$ 12,$77 77.7 .755 %tu %tu3h 3hr r 1#. %ased on on problem problem no. 15, 15, what what is the factor factor of of evaporatio evaporation* n* Answer: A
A. %. C. '.
1.0 1.52 1.1" 1."5
20. %ased on problem problem no. 15, 15, calculate calculate the over=all over=all thermal thermal efficien efficienc+T* c+T* Answer: A A. &".02< %. &0.2"< C. &7.2"< '. 72.1$< 21. %ased on problem problem no. 15, 15, determine determine the actual actual specific specific evaporatio evaporationn in ( per ( coal. Answer: A A. 7.$7 (steam3(coal %. 7.57 (steam3(coal C. 7.2$ (steam3(coal '. &.2" (steam3(coal 22. %ased on problem no. 15, determine the euivalent euivalent specific evaporation in ( per ( coal. Answer: A
A. %. C. '.
7.#5 (steam3(fuel .$7 (steam3(fuel 7."5 (steam3(fuel 7.5 (steam3(fuel
2$. An au8iliar+ au8iliar+ boiler boiler produce producess steam at bar :0.0 :0.0 @!a;, 0.# dr+ dr+ from feedwater feedwater at "$ ºC, ºC, and fuel of calorific value of "2 @3( is burned at the rate of 1.2 tons per da+. Assumin( an efficienc+ of 70<, calculate the steam production per hour. Answer: A 6team at bar :0.0 @!a; hf 721 3( hs hf hf( hf( 20" 3( 7210.#:20"; 272 3( )ater at "$ ºC9 h "$:".17; 10.0" 3( A. 57&. 57&.#$ #$ (3h (3hr r %. "7&. 7&.&& (3 (3hhr C. $7&." 7&."55 (3 (3hhr '. 275. 275.$5 $5 (3h (3hr r 2". 'urin( 'urin( a test on an oil=fier oil=fierdd boiler boiler the follin( follin( data data were recorded recorded99 !ressure of steam 2.5 @!a /emperature of steam $00 ºC @ass of feedwater enterin( the %oiler 11$50 (3hr /emperature of Feedwater 100 ºC @ass of fuel burned 75 (3hr Calorific value "2.$ @3( 6team at :25 bar; 2.5 @!a, $00 ºC h $010 3( )ater at 100 ºC h "1#.10 3( Calculate the efficienc+ of the boiler. boiler. Answer: A A. 7#."#< %. 7."#< C. 5$."#< '. $".57<
25. Fuel Fuel of calori calorific fic value value "$.5 @3( @3( is burned burned in an au8ili au8iliar+ ar+ boiler boiler at the rate of 1 (3hr (3hr. /he feedwater rate is 0.25 (3s and its temperature is " ºC. ?f the efficienc+ of the boiler is &< and the steam produced is dr+ and saturated, estimate its pressure. Answer: A A. 1.1 @!a %. 1.5 @!a C. 2.0 @!a '. 2.1 @!a 2&. /he euiva euivalen lentt evaporat evaporation ion of a boile boilerr, from from and at 100 ºC is 15 ( steam steam per ( fuel fuel and the calorific value of the fuel burned is "1.# @3(. Find the efficienc+ of the boiler. Answer: A A. 0.1< %. 7.#&< C. 2.$< '. 77.7< 27. )hat is the the developed boiler boiler horsepower if the steam rate is 0.5 (3s (3s and the the factor of evaporation evaporation is 1.25. Answer: A A. 2""."1 ."1-p %. 21".5" .5" -p C. 200.57 .57 -p '. 157.25 .25 -p -p 2. /he heatin( heatin( value of fuel fuel suppled suppled in a boiler is "0,000 "0,000 3(. ?f the factor factor of evaporation evaporation is 1.10 1.10 and the actual specific evaporation is 10, what is the efficienc+ of the boiler* Answer: A A. &2.07< %. 5$.0< C. 77.05< '. 5".#7< 2#. 6team at $0 bar :$ @!a;, @!a;, $75 ºC is (enerated (enerated in a boiler boiler at the rate of $0,000 $0,000 (3hr from from feed water at 1$0 ºC. the fuel has a calorific value of "2 @3( and the dail+ consumption is 5$ tons. Calculate the boiler efficienc+. 6team !roperties9 6team at $0 bar :$ @!a;, $75 ºC9 h $1" 3( )ater at 1$0 ºC9 h 5"& 3(. Answer: A A. 5< %. 75< C. < '. #5< $0. A boiler boiler contains contains $.5 tons of water water initiall+ initiall+ havin( "0 ppm dissolv dissolved ed solids and and after 2" hrs the dissolved solids in the water is 2500 ppm. ?f the feed rate is 75 (3hr, find the ppm of dissolved solids contained in the feed water. Answer: A A. "10 ppm %. $20 ppm C. $#0 ppm '. "20 ppm
$1. A fu fuel of of Rh &, Cal was burned in the furnace of 22$ m 2 water tube boiler which was (eneratin( 5,""$ ( steam per hour at 1".0& ( per cm 2 abs. dr+ and saturated, from 10# ºC feed, at a time when fuel consumption was &12 ( per hour. Find the percent ratin(. Answer: A A. 1"&< %. 150< C. 2$0< '. 157< $2. stimate the the reuired furnace volume volume for a pulveriLed coal=fired coal=fired steam steam (enerator where 1$75 8 10 " Cal per hour of heat transfer at 0< thermal efficienc+ is the e8pected thermal performance. %oiler has water walls. Ash fusion temperature is 120" ºC and the desi(n value of furnace heat release rate is 1#5,00 Cal per m$ per hour. Answer: A A. 7.7# m$ %. #.5& m$ C. 2.$5 m$ '. 1."5 m$ $$. /wo boilers boilers has capacities capacities of 200 (3hr (3hr and 250 (3hr. (3hr. if 150,000 ( of coal are supplied supplied to two boilers, how man+ da+s to to consume the available available fuel* Answer: A A. 1$.# $.# da+ da+s %. 17.7 da da+s C. 15.7 da da+s '. 2" da+s $". )hat is the net boiler boiler efficien efficienc+ c+ if the heat (enerated (enerated b+ fuel is "0,000,0 "0,000,000 00 3hr 3hr and the boiler boiler au8iliaries consumes 2 @). /he A6@ evaporation evaporation units of a boiler is 25,#00,000 3hr. 3hr. Answer: A
A. %. C. '.
"&.75< $&.75< 5&.75< &.75<
$5. /estin( estin( of a stoer=f stoer=fired ired boiler boiler reveal that, that, durin( durin( a period when "550 "550 lb of 12,"00 %/ coal were burned, refuse accumulated in the ashpit to the e8tent of "#5 lb, althou(h the coal as fierd contained onl+ 10< ash b+ anal+sis. 'etermine the (rate efficienc+ if this stoer considerin( no fl+=ash. Answer: A A. #.#7< %. #2.$5< C. #5.7< '. #0.21< $&. A travell travellin(=( in(=(rate rate stoer stoer can burn bituminou bituminouss coal with 10< moistur moisturee and 10< ash at a rate of 2 500,000 %/3hr=ft . A boiler boiler with a steam ratin( of 200,000 lb3hr will be fired with the above fuel havin( a hi(h heat value of 12,200 %/3lb. if the boiler efficienc+ is 0<, and if it taes 1000 %/ to evaporate and superheat one pound of feedwater to the desired temperature, find the hourl+ coal suppl+ and (rate area neened. Answer: A A. 20,5 20,500 00 lb, lb, 500 500 ft=2 %. 2&," 2&,"00 00 lb, lb, 700 700 ft ft2 C. 2,2 2,200 00 lb," lb,"00 00 ft2 '. 22,& 22,&00 00 lb, lb, 200 200 ft2
$7. )hat is the rate rate of evaporation evaporation of a water tube boiler boiler if the factor factor of evaporation evaporation is 1.10, percent percent 2 ratin( of 200< and the heatin( surface area is is 250 m * Answer: A A. 7,1 7,17. 7.1& 1& (3 (3hr hr %. 7,# 7,#. .&7 &7 (3h (3hr r C. &,7 &,7#. #."5 "5 (3h (3hr r '. 5,7& 5,7&. .5" 5" (3 (3hr hr $. An oil=fired oil=fired steam steam boiler boiler (enerates (enerates 1$,000 1$,000 lb of steam steam per hour at $00 psia, psia, &50 ºF when when the fuel is burned at 120 (allons per hour. Feedwater, $00 ºF. ºF. calculate the thermal efficienc+ and euivalent evaporation per lb of fuel oil. Answer: A A. 77.0 77.0#< #< B 15. 15."" lb lbsteam3lbfuel %. 7.0 7.0#< #< B 1#. 1#.77 lb lbsteam3lbfuel C. 7#.07 #.07< < B 12.5 12.5lb lbsteam3lbfuel '. #.07< B 1. lbsteam3lbfuel $#. ne hundred hundred thousa thousand nd pounds pounds of water water per hour hour at 750 psia psia and 250 ºF ºF :h f 2$0.# %/3lb; are received b+ a steam (eneratin( unit. 6team leaves the superheater at &50 psia and &00 ºF :h s 12&.5 %/3lb;. the fuel used is coal whose heatin( value is 12,500 %/3lb. Calculate the wei(ht of fuel fired per hour if economiLer efficienc+ is 5<. Answer: A A. "."" "."" lon( lon( tons tons per per hour hour %. 5."" 5."" lon lon(( tons tons per per hou hour r C. $."$ $."$ lon lon(( tons tons per per hou hour r '. 1."5 1."5 lon( lon( tons tons per per hour hour "0. A fire=tu fire=tube be boiler boiler operates operates at 200 psia psia :1.$7 :1.$7 @!a; with 200 ºF :#$.$ :#$.$ ºC; feedw feedwate ater, r, both both at saturated condition. /he diameter of the boiler is 21$." cm, len(th of 5.5 m, and havin( " tubes, 10.2 cm inside diameter, 10.5 cm outside diameter. 'etermine the boiler heatin( surface in m 2 and the wei(ht of steam (enerated in (3s if the boiler evaporates $".5 lb3hr of water per 12 ft 2 of heatin( surface or $.# (3m 2=s* Answer: A A. 2,$& 2,$&0. 0.&7 &7 (3 (3hr hr %. 1,2$ 1,2$". ".57 57 (3h (3hr r C. $,2" $,2"7. 7.7& 7& (3h (3hr r '. ",57 ",57&. &.& & (3 (3hr hr "1. )et steam is bein( bein( (enerated (enerated b+ a boiler boiler at the rate of 1500 1500 ( per hour from 2&.7 2&.7 ºC feed water. water. 2 Rualit+ of the steam is #< and (au(e shows a pressure of # (3cm . Calculate the euivalent evaporation and the heat absorbed b+ the boiler per hour in Cal when producin( steam* Answer: A
A. %. C. '.
17"$ 17"$.7 .722 (3 (3hr hr 2$7& 2$7&." ."22 (3h (3hr r 1#7 1#7.7 .7"" (3h (3hr r 12$5 12$5.7 .7&& (3 (3hr hr
"2. )hat is the total total pressure pressure loss in steam steam pipe 1&" m lon( if the euivale euivalent nt pressure pressure loss is 50 !a per $0 meters* Answer: A A. 27$ !a %. 17$ !a C. $72 !a '. "7$ !a "$. A hi(h hi(h temperature source source at #50 > provides provides 50 heat heat to a heat en(ine. en(ine. /he heat en(ine en(ine converts 200 net wor and reects the balance to a temperature sin at 2#5 >. compare the thermal
efficienc+ t of this en(ine to the thermal efficienc+ rev of the Carnot c+cle reversible heat en(ine. Answer: C
A. t rev %. t U rev C. t V rev '. t W rev "". A 150 (rams (rams of water at 75 ºC is heated at constant constant pressur pressure. e. /he water water is completel+ completel+ vaporiLed vaporiLed.. Find the heat added. Answer: C A. 5"$.52 .52 %. 1&.&& .&& C. $5".25 .25 '. 11$5.& $5.&&& STEAM PRIME MOVERS
1.
6team is admitt admitted ed to the the c+linder c+linder of an en(in en(inee in such a manner manner the the avera(e avera(e pressur pressuree is 120 psi. psi. the diameter of the piston is 10 in. and the len(th of stroe is 12 in. )hat is the -p of the en(ine when it is main( $00 rpm* Answer: A A. 171.5 -p %. 175 -p C. 17$.2 -p '. 17"." -p
2.
/he area area of an indica indicator tor card card taen taen off the the hi(h hi(h pressure pressure c+lind c+linder er of a uadrup uadruple le e8pansio e8pansionn en(ine en(ine 2 is 1""5 mm , the len(th is 0 mm, and 1 mm of hei(ht represents 0.27 bar. /he bore of the c+linder runs at 1.&5 rev3sec. Calculate the total indicated power of the en(ine assumin( eual powers are developed in all c+linders. 4ote9 len(th of stroe 105 mm and diameter of &00 mm. Answer: A A. 1#11 #11.2 ) %. 2$"5.7 ) C. 112$.5 ) '. 2$$1. $$1."$ "$ )
$.
'urin( 'urin( a test on a sin(le= sin(le=c+l c+lind inder er steam steam en(ine, en(ine, the mean effec effectiv tivee pressure pressure was was "05 !a when runnin( at $ rev3sec. /he brae load was 1.# 4 actin( at an effective radius of 1.2 m. ?f the c+linder diameter is 0.275 m and stroe 0." m, calculate the mechanical efficienc+. efficienc+. Answer: A A. 7"."&< %. ".5"< C. 7$.2"< '. 2$."5<
".
A steam steam en(ine en(ine has has anindica anindicated ted efficie efficienc+ nc+ of &5<. &5<. /he /he enthalpie enthalpiess of the en(in en(inee at entrance entrance and and e8it are $000 3( and 2500 3( respectivel+. ?f the mechanical efficienc+ is 5< and the steam consumption is 1000 (3hr, (3hr, what is thebrae power of the en(ine* Answer: A A. 7&.&") %. 7.5" ) C. 7.&7 ) '. 2.$" ) )
5.
6tea 6team m at 7.5 bar is admit admitte tedd to an en(in en(inee c+lind c+linder er and cut= cut=of offf at 0.$" 0.$" of the the stro stroe e.. /he bac bac pressure is 1.7 bar. bar. 4e(lectin( clearance, calculate the h+pothetical mean (ross pressure and mean effective pressure. Answer: A A. 5.$0 5.$011 bar bar B $.&0 $.&011 bar bar %. 5.&0 5.&011 bar bar B 2.& 2.&02 02 bar bar C. 5."& 5."&77 bar bar B 2." 2."57 57 bar bar '. ".57 ".57 bar bar B $."5 $."5"7 "7 bar bar
&.
6team is is supplied supplied to the c+lind c+linder er of an en(ine en(ine at .$ bar bar and cut=of cut=offf taes place when when the the piston piston has traveled 0."5 of its stroe. /he clearance volume is eual to 5< of the stroe volume. ?f the bac pressure is 2." bar, calculate the actual mean effective pressure tain( a dia(ram factor of 0.72. Answer: A
A. %. C. '.
$.17 .17 ba bar $."7 ."7 bar 2."5 ."57 bar 2.57 .57" ba bar
7.
/he mean mean effect effective ive press pressure ure of an en(in en(inee runnin( runnin( at $00 $00 rpm is 500 !a. !a. )hat )hat is the indica indicated ted power if the en(ine has bore bore of 250 mm 8 "50 mm. Answer: A A. 110.5 ) %. 210.7 ) C. 12$.5 ) '. $12." ) )
.
/he c+lin c+linder der of a triple triple e8pans e8pansion ion en(in en(inee are &00, #50 #50 and 1500 1500 mm diameter diameter and and the stroe stroe is 1050 mm. )hen runnin( at 1. rev3s, the mean effective pressures in the c+linders are 517, 207 and $ !a respectivel+. Calculate the total indicated power of the en(ine. Answer: A A. 1&&1. ) ) %. 2$"5.7 ) C. 2"57.7 ) '. 175. 75.$" $" )
#.
6team at at 1.5 @!a, @!a, $00 ºC ºC is suppli supplied ed to an an en(ine en(ine and e8hau e8haust st at 0.01" 0.01" @!a. @!a. /he /he consumpti consumption on of steam is 2,500 (3hr when the indicated power is $000 ). Calculate the steam consumption on (3)=hr and the indicated thermal efficienc+. Answer: A A. #.5 (3) (3)=hr =hr,, 1$."5 1$."5< < %. .5 (3) (3)=hr =hr,, 12.$ 12.$"< "< C. 10 (3) (3)=hr =hr,, 11." 11."5< 5< '. 10.5 10.5 (3) (3)=hr =hr,, 10."7 10."7< <
10. A steam steam en(ine en(ine delive delivers rs 1000 (3hr (3hr steam steam.. /he enthalp enthalpies ies at entra entrance nce and e8it of the en(ine en(ine are$000 3( and "00 3( respectivel+. Calculate the brae power of the en(ine if the brae thermal efficienc+ is 20<. Answer: A A. 1""."" ."" ) ) %. 200."5 ."5 )
C. 25".$" .$" ) '. $"5.75 .75 ) )
11. 11. An en(ine en(ine is supplied supplied with with steam at a pressure pressure 1.5 @!a and tempera temperature ture 250 ºC, ºC, and pressure pressure of the e8haust is 0.01& @!a. Assumin( Assumin( isentrop isentropic ic e8pansion e8pansion find the dr+ness dr+ness fraction of the steam after e8pansion. Answer: A 6team !roperties9 At 1.5 @!a, 250 ºC 6 &.711 3(> At 0.01& @!a9 6f 0.722 3(=> 6f( 7.21$ 3(=> A. 0.2$5 %. 0.#7 C. 0.7&# '. 0.7&5" 12. A double double actin( actin( steam steam en(ine en(ine with bore bore and stroe stroe of 250 mm 8 "50 "50 mm rotates rotates 250 rpm. ?f the the mean effective pressure is "00 !a, what is the indicated power developed in the c+linder* Answer: A
A. %. C. '.
7$.&$ ) ) 7.57 ) ".75 ) 5.57 ) )
1$. ?n a test laborator+ laborator+,, it was found out that of the 0 %-! develo developed ped b+ the en(ine en(ine on test, "5 -p are absorbed b+ the coolin( water that is pumped throu(h the water acet and the radiator. /he water enters the top of the radiator at 200 ºF. At that temperature, enthalp+ of water is 1&.07 %/3lb. )ater leaves the bottom of the radiator at 1#0 ºF and with an enthalp+ of 15.0$ %/3lb. )hat is the water flow rate of stead+=state operation* Answer: A A. 22. 22. (al3 (al3mi minn %. 52.$ 2.$ (al (al3m 3min in C. 12.5 12.5 (al3 (al3mi minn '. 1.# 1.#55 (al (al3m 3min in 6/A@ /E%?4 :sample problems; 1". An indust industria riall plant reuir reuires es 1.5 ( of dr+ satura saturated ted steam steam per second second at 1&5 ºC for heati heatin( n( purposes. /his steam ma+ be supplied from an e8traction turbine which receives steam at " @!a and $0 ºC and is e8haust to condenser at the rate of 0.0 ( steam per second at 0.00$" @!a while reectin( 1"00 ) to the coolin( water. ?f the mechanical=electrical efficienc+ is #5< and that the heat loss in the turbine casin( is 10 ), ), calculate the power (enerated b+ the plant. Answer: A A. 155&.5 ) )
%. 17#.7 ) C. 17#."5 ) ) '. 1"#. "#.55 55 ) 15. 6team enters enters a turbine turbine sta(e with an enthalp+ enthalp+ of $&2 3( 3( and a velocit+ velocit+ at 70 m3s and leaves leaves the same sta(e with an enthalp+ of 2"& 3( and a velocit+ of 12" m3s. Calculate the power if there are 5 (3s steam admitted at the turbine throttle* Answer: C A. "5#7. 5#7."5 "5 ) %. $#7&.55 ) ) C. $$.1 ) ) '. 1&75. &75."2 "2 ) 1&. An adiabatic adiabatic turbine turbine in a steam (enerati (eneratin( n( plant receive receivess steam at a pressure pressure of 7 @!a and 550 ºC and e8haust at 20 !a. /he turbine inlet is $ m hi(her than the turbine e8it, the inlet steam velocit+ is 15 m3s and the e8it velocit+ is $00 m3s. Calculate the turbine wor per unit mass of steam. Answer: A
A. %. C. '.
11#&. 1#&.&0 &0 3 3( ( 12"# 12"#.7 .7 3 3(( 157 57.5 3( 3( 1&75 1&75." ."22 3 3((
17. A steam steam turbin turbinee with an intern internal al effici efficienc enc++ of #0 percen percentt receive receivess steam steam at 7 @!a 550 ºC and e8haust at 20 !a. 'etermine the ideal turbine wor, e8haust enthalp+ and the e8it ualit+ of steam. :se the properties of steam in problem no. 1&;. Answer: A A. 12"1.22 12"1.22 3(, 3(, 2"1$.02 2"1$.02 3(, 3(, #1.&#< #1.&#< %. 1151.22 1151.22 3(, 3(, 2"1$.02 2"1$.02 3(, 3(, #1.&#< #1.&#< C. 12"1.22 12"1.22 3(, 3(, 251$. 251$.02 02 3( 3(,, #2.&#< #2.&#< '. 1"21.22 1"21.22 3(, 3(, 21"$.02 21"$.02 3(, 3(, #&.#1< #&.#1< 1. 6team with with an enthalp+ enthalp+ of 00 Cal3( enters enters a noLLle noLLle at a velocit+ of 0 m3s. Find Find the velocit+ velocit+ of the steam at the e8it of the noLLle if its enthalp+ is reduced to 750 Cal3(, assumin( the noLLle is horiLontal and disre(ardin( heat losses. /ae ( #.1 m3s2 and constant "27 (=m3Cal. Answer: C A. "52.$ 52.$77 m3s m3s %. 2"5."5 ."5 m3 m3s C. &51.#2 .#2 m3 m3s '. "27.5 27.5"" m3s m3s 1#. 6team is e8panded e8panded throu(h throu(h a noLLle noLLle and the enthalp+ drop per ( of steam from the initial initial pressure pressure to the final pressure is &0 . 4e(lectin( friction, find the velocit+ of dischar(e dischar(e and the e8it area of the noLLle to pass 0.20 (3s if the specific volume of the steam at e8it is 1.5 m $3(. Answer: D A. $"&. $"&."" m3s m3s,, 7# 7# m2 %. $5&. $5&.77 m3s m3s,, 27 27 m2 C. 7&5. 7&5.&& m3s m3s,, "&7 "&7 m2 '. $"&. $"&."" m3s m3s,, && && m2 20. /he entrance entrance and e8it enthalpies enthalpies of a steam turbine are "000 and $000 $000 3( respectiv respectivel+ el+.. )hat is the mass of steam enterin( the turbine if the (enerator power is $ @) and (enerator efficienc+ is #0<. Answer: A A. 12,0 12,000 00 (3h (3hr r %. 1",00 ",0000 (3 (3hhr
C. 17,00 7,0000 (3 (3hhr '. 2",0 2",000 00 (3h (3hr r
21. 'r+ saturate saturatedd steam at bar :0. :0. @!a; is e8panded e8panded in turbine turbine noLLle noLLle to a pressure pressure of 5 bar 0.#7 0.#7 2 dr+. Find the velocit+ at e8it. ?f the area at e8it is 1".5 cm , find the mass flow rate of the steam in (3s. Answer: A 6team !roperties9 At 5 barD :0.5 @!a; At bar :0. @!a; $ hf &"0 3( v 0.$7" m 3( h( 27&# 3( hf( 210# 3( A. 1.&2 1.&255 (3s (3s,, "07. "07."" m3s m3s %. 2."5 2."5&& (3 (3s, s, 7& 7&.5 .5 m3s m3s C. 2.25 2.2577 (3 (3s, s, 2$$ 2$$. . m3s m3s '. $.12 $.1255 (3s (3s,, 125. 125.77 m3s m3s 22. A steam steam turbine has an an entrance enthalp+ of $000 3( and an e8it enthalp+ enthalp+ of 2000 3(. 3(. )hat is the sta(e efficienc+ if the actual enthalp+ after isentropic e8pansion is 2,200 3(* Answer: D A. 2< %. 70< C. &< '. 0< 2$. ?n a Eanine c+cle, c+cle, steam turbine turbine with e8haust e8haust enthalp+ enthalp+ of 2500 2500 3( delivers delivers 0.50 (3s (3s of steam. ?f the e8it enthalp+ of the condenser is 500 3(, what is the heat reected* Answer: A A. 1000 ) %. 1200 ) C. 1700 ) '. 1500 >w 2". 6team enters enters the noLLle noLLle of an impulse impulse turbine turbine at 2 @!a, $00 ºC and leaves at 0.$0 @!a, @!a, 0.# dr+. dr+. /he an(le of the noLLles is 20º to the direction of motion of the blades and blade velocit+ is $0 m3s. Calculate the velocit+ of the steam leavin( the noLLles. Answer: A A. 2#." m3s %. #2". m3s C. 5"5.7 m3s '. 75". m3s 25. 6team enters the the turbine at the rate of 11,000 11,000 (3hr with enthalpies enthalpies of $000 3( and 1000 1000 3( at the entrance and e8haust respectivel+. 6team is e8tracted from the turbine at $500 (3hr for heatin( purposes with enthalp+ enthalp+ of 2700 3(. 3(. Calculate the turbine wor. wor. Answer: C A. 5,"& ,"&.$ .$$$ ) ) %. ",5&# ,5&#.$ .$$$ ) C. ","5 ,"5.$ .$$$ )
'. 5,"25 ,"25.$ .$$$ ) ) 2&. After checin( checin( on the propertie propertiess and phase descripti descriptions ons of water, water, the ualit+ is found found to be 8 0.70. -ow man+ percent of the mass is in the liuid phase* Answer: D A. 70< %. 0.70< C. 100< '. $0< 27. An en(ine en(ine reuires reuires "$00 of dr+ steam per hour hour. /he ualit+ ualit+ of steam is #0<. #0<. )hat must be the wei(ht of steam* Answer: A A. "77 77 ( (3hr 3hr %. "000 ( (3hr C. 525 ( (3hr '. &000 000 ( (3hr 3hr 2. /he pressure pressure and temperatu temperature re enterin( enterin( the turbine turbine are 100 !a and $0 ºC. /he pressure pressure leavin( leavin( the turbine is 20 !a. /he /he ualit+ of the steam enterin( the condenser condenser is #0<. )hat is the the turbine wor* Answer: D 6team !roperties9 N 100 !a and $0 ºC :h $207.2 3(; N 20 !a, h f 251." 3( and h ( 2&0#.7 3( A. 1$$ 1$$.$ .$$$ 3 3( ( %. 1$$$. $$$. 3 3( C. 5#7.5 #7.5 3 3(( '. $$. $$.$$ $$ 3 3(( 2#. A & @) steam turbine turbine (enerato (eneratorr power plant plant has a full=load full=load steam rate of (3)=hr (3)=hr.. assumin( assumin( that no=load steam consumption as 15< of full=load steam consumption, compute for the hourl+ steam consumption at 75< load, in (3hr. Answer: A A. $7, $7,00 00 (3h (3hr r %. $,70 ,7000 (3 (3hhr C. $0,7 0,700 (3 (3hhr '. $0, $0,70 70 (3h (3hr r $0. A " ( air enters enters a turbine turbine with enthalp+ enthalp+ of &00 and veloci velocit+ t+ of 250 m3s. /he /he enthalp+ enthalp+ at e8it is "& and velocit+ of 170 m3s. )hat is the wor developed if there is a heat loss of 10 * Answer: B
A. %. C. '.
12.$ .$ 171.2 0.2 2.$
IA6 J! 1.
Iiven a horiLonta horiLontall conve+or conve+or,, "& m centers, centers, 175 175 pounds pounds per per hour capaci capacit+ t+ of handli handlin( n( bitumino bituminous us $ coal at 0.5 m3s with 00 (3m . ther data as follows9 Fli(ht width and depth &10 mm 8 200 mm Rualit+ of material 0.10 m $3m Coefficient of friction elements 0.10 @aterial Coefficient of friction 0.5#
Assume an en(ineerin(=t+pe chain with sleeve bearin( rollers wei(hin( with fli(hts, #.$ (3m. Calculate the chain pull in (. Answer: D A. 210.$$ %. "550.10 C. 1555.$& '. $1&&."&
2.
)hat )hat is the power power in ) reu reuir ired ed to drive drive a hori horiLo Lont ntal al conve conve+o +orr "& m cent center ers, s, 175 tons tons33 hr $ capacit+ of bituminous coal at 0.5 m3s with 00 (3m material* ther data are as follows9 Fli(ht width and depth &10 mm 8 200 mm Rualit+ of material 0.10 m $3m Coefficient of friction elements 0.10 @aterial Coefficient of friction 0.5# Assume an en(ineerin(=t+pe chain with sleeve bearin( rollers wei(hin( with fli(hts, #.$ (3m. Jet Fp 7&.0"2 (=m3-p=s. Answer: C A. 10.20 ) ) %. 20.50 ) C. 15.5$ ) '. $0.15 ) )
$.
A chain chain (rate (rate stoer stoer #.5 #.5 ft, wide, wide, receive receivess crushed crushed coal havin( havin( a mean specif specific ic wei(ht wei(ht of 5" 5" lb3ft lb3ft $. /he coal is spread to a uniform depth of &. in. b+ the coal (ate. 'etermine the stoer speed in fpm if the furnace is to burn 7.5 tons per hour. Answer: A A. 0.& .& ft ft3min 3min %. 0# ft ft3min min C. 1.& .& ft3m ft3min in '. 1.# .# ft ft3min 3min
".
Find the the len(th len(th of a suspens suspension ion buner buner to contain contain 11 tons tons of coal coal without without surch surchar(e ar(eDD width, width, ".& mD depth ".$ m. the level capacit+ of a suspension buner is 53 wdJ9 where w width, d depth and J len(th. 'ensit+ of coal, 00 (3m $. Answer: A A. 1.$0 m %. 12$.0 m C. 17.&1 m '. 12.&1 m
5.
Calculate Calculate the the belt width width of of a conve+or conve+or to trans transport port 1 1 tons per per hour hour at 20 º len(th len(th suffi sufficien cientt to (ive (ive $$.5 m rise. 1750=rpm motor, =velt drive to helical (ear speed reducer. %elt speed, &1 m3min. dischar(e over tail pulle+. Answer: B A. 25."1 cm cm %. 27.0$ cm C. $5."1 cm '. $7.0$ cm cm
&.
/he individ individual ual bucets bucets of a vertical vertical elevat elevator or carr+ $.& ( coal coal and are are spaced spaced $0.5 cm cm apart on on the chain. 6procet wheels &1 cm diameter, chain speed 7#.2 m3min. he(ht between sprocets, #.1 m. drive9 1750=rpm motor throu(h sprocets and steel roller chain. )hat is the motor horsepower reuired to drive the conve+or drive shaft* Answer: C
A. %. C. '.
2 -p " -p 5 -p $ -p
7.
An open coal +ard +ard has dimension dimensionss $&.& m 8 15.2 15.2 m. how how man+ tons tons of coal coal can be stocpi stocpiled led on itit to a depth of $.05 m sides slopes $5º. Answer: C A. 0".2 0".2&& to tons %. 1000. 000.&2 &2 ton tons C. #00.1 00.122 tons tons '. 75".7 5".7## to tons
.
Find the the draft draft loss loss in rectan rectan(ula (ularr breechin( breechin( 2.5# m 8 $0." $0." m lon( lon( when 1#& m $3s flue (as of 0.7&# (3m $ densit+ are flowin(. Answer: D A. 2.5 .50 cm -2 %. 2.0 .0& cm -2 C. 1.5 .50 cm -2 '. 1.0 .05 cm -2
#.
A forced forced draft draft fan when driven driven b+ a constan constantt speed speed motor motor produces produces a pressu pressure re of 20.$2 20.$2 cm water water $ when R 1"15. m 3min. what pressure would it produce on same air if R were made 11&5." m$3min. )hat would be the relative speed and power* Answer: A A. 52 cm cm, of of -2, 1.&0 41, ".1 !1 %. 50 cm cm, of of -2, 1.0 41, ".0 !1 C. "5 cm cm, of of -2, 1.&0 41, ".1 !1 '. "7 cm cm, of of -2, 1.1 41, ".1 !1
10. /he products products of combusti combustion on of &$5 ( coal per hour hour pass throu(h throu(h a breechin( breechin( at 2&0 ºC and 7.&2 m3s. 8cess air, 50<. Assume suare section breechin( and find its dimensions. 6ea level, and densit+ of the flue (as=coal fired 0.& (3m $. Answer: A ltimate anal+sis of coal is as follows9 6ulfur 0.55< 4itro(en 1.17< -+dro(en ".5< 8+(en &.0$< Carbon ".02< Ash $.7$< A. 77 cm cm 8 77 cm %. && cm cm 8 && cm cm C. cm cm 8 cm cm '. 55 cm cm 8 55 cm FEED WATER LOOP
1.
/he feedwa feedwater ter to a boiler boiler is #2< conden condensat satee and < mae=up mae=up contai containi nin( n( 270 ppm solid solids. s. )hat )hat wei(ht of solids enter the boiler per hour at 22,&0 (3hr steam evaporation. Answer: A A. 0."# 0."# ( soli solids ds3h 3hr r %. 05# 05# ( soli solids ds3h 3hr r C. 0.$# 0.$# ( soli solids ds3h 3hr r '. 0.&# 0.&# sol solid ids3 s3hr hr
2.
-e 1$70 1$70 diameter diameter steam steam drum drum on a boile boilerr is 2""0 2""0 mm lon( lon( has a 250 250 mm (au(e (au(e (lass (lass at at mid=drum mid=drum level. Find the ma8imum steam (eneration that could be cared for b+ a blowdown of half a water (au(e each hr. shift. !ressure, 17.5 (3cm 2 (a(e. 6f 150 ppm, 6 b 2000 ppm. Answer: B A. "50. "50."# "# (3h (3hr r %. 550.5 50.5## (3 (3hhr C. &50.5 50.5## (3 (3hhr '. 750. 750.5# 5# (3h (3hr r
$.
/he e8hau e8haust st of a mechanic mechanical al drive drive turbin turbinee is estimat estimated ed to be 1270 1270 (3hr (3hr at 1" (3cm (3cm 2 (a(e, and 250 3(. -ow much feedwater will this heat per hour with 2.7 ºC terminal difference :tdº;* Cold water temperature, 2&.7 ºC Answer: C A. 1,1 1,1"& "&.0 .0"" (3h (3hr r %. 1&,1 1&,1" ".0 .0"" (3h (3hr r C. 11,"& 1,"&.0 .0"" (3h (3hr r '. 1",1 1",1& &.0 .0"" (3h (3hr r
".
stimate stimate discha dischar(e r(e rate rate :J3min; :J3min; and ma8imum ma8imum suction suction lift lift of a #5 #5 mm 8 127 127 mm 8 152 152 mm duple8 duple8,, direct=actin( steam pump. v 0.#0 sea level. Answer: D A. 17. 17.#0 #0 J3mi J3minn %. 27.# 7.#00 J3m J3miin C. "7.# 7.#00 J3m J3miin '. $7. $7.#0 #0 J3mi J3minn
5.
Calcu Calculat latee drive drive horsepo horsepower wer for for pumpin( pumpin( 170$ 170$ J3min J3min cold cold water water to a tan tan suction suction at 127 127 mm -( 2 vacuum, deliver+ at 5.$ (3cm (a., both measured close to pump, e p 0&5. Answer: A A. $1."2 -p %. 20."2 -p C. $5."2 -p '. 2$.02 -p GEOTHERMAL POWER PLANT
1.
A liuid liuid domina dominated ted (eothe (eotherma rmall plant with with a sin(le sin(le flash flash separat separator or receives receives water water at 20" ºC. /he separator pressure is 1.0" @!a. A direct contact condenser operates at 0.0$" @!a. /he turbine has a pol+tropic efficienc+ of 0.75. For a c+cle output of 50 @), what is the mass flow rate of the well=water in (3s* Answer: A A. 2100 %. 271 C. 1&7 '. 2"""
2.
A (eothe (eothermal rmal power power plant plant draws draws a pressur pressuriLed iLed water water from from well at 20 20 @!a and $00 $00 ºC. to produce produce a steam=water mi8ture in the separator, where the unflashed water is removed, this water is throttled to a pressure of 1.5 @!a. /he flashed steam which is dr+ and saturated passes throu(h the steam collector and enters the turbine at 1.5 @!a and e8pands to 1 atm. /he turbine efficienc+ is 5< at a rated power output of 10 @). Calculate the over=all plant efficienc+. Answer: A A. 7.2&< %. 5.2< C. 10.7< '. 12.7<
$.
A flash flashed ed steam steam (eothe (eotherma rmall power power plant plant is locate locatedd where where under under(ro (round und hot hot water water is availab available le as saturated liuid at 700 !a. /he well head pressure is &00 !a. /he flashed steam enters a turbine at 500 !a and e8pands to 15 !a, when it is condensed. /he flow rate from the well is 2#.& (3s. 'etermine the power produced in ). ). Answer: D A. "5$.1& .1& ) ) %. 5"0.$& .$& ) C. 25".25 .25 ) '. "$0.1& .1& ) )
".
?n a certai certainn (eotherm (eothermal al area, area, studi studies es show that that 1,500,0 1,500,000 00 (3hr (3hr of pressuri pressuriLed Led (round (round water water is available at 2500 psia and &20 ºF the water will be throttled to 250 psia to produce wet steam and this mi8ture will be passed throu(h a water separator to remove the water droplets so that saturated steam at 250 psia is available at the entrance of steam turbine for the proposed power plant. ther data are as follows9 'ischar(e pressure of turbine 25 in. -( vacuum /urbine n(ine efficienc+ 75< @echanical Joss 1.5< of shaft power Ienerator efficienc+ #7< Assume atmospheric pressure to be $0 in -(. 'etermine the ma8imum amount of power in ) that the plant can (enerate. Answer: C A. 5$.1& @) @) %. 0.$& @) C. &.0& @) '. "$.1& @) @)
5.
A flashed flashed steam steam (eotherma (eothermall plant has has pressuriL pressuriLed ed under(r under(round ound water water availab available le at 102 (3cm (3cm 2 and 2"0 ºC. in order to produce steam=water mi8ture, the (round water is passed and throttled to 5." (3cm2 in a steam separator. /he dr+ steam produced in the separator is fed to double flow impulse and reaction turbine with (uaranteed en(ine efficienc+ of 5<. /he turbine is directl+ coupledto a $ phase, &0 -L, 0< power factor, 1$00= air cooled (enerator. 8haust is to be direct=contact spra+ t+pe main condenser desi(ned to operate a vacuum of &"7.5 mm -(. Ienerator efficienc+ is #5<, (round water is "5# (3s. )hat is the enthalp+ of steam=water mi8ture in the steam separator* Answer: A A. 10$ 10$.1 .100 3 3( ( %. 12"5 12"5.7 .7 3 3(( C. 15"$ 15"$.2 .255 3 3(( '. 1052 1052.$ .$55 3 3( (
&.
%ased on on the data data in problem problem 4o. 4o. 5, what what is the the enthalp enthalp++ of steam steam enterin enterin(( the turbi turbine* ne* Answer: C A. 27& 27&.& .& 3 3( ( %. 17" 17".& .&77 3 3(( C. 2751. 751.$$ 3 3( '. $57" $57"." ." 3 3((
7.
%ased on the the data data in in problem problem 4o. 5, what what is is the the enthalp enthalp++ of the e8haust e8haust steam* steam* Answer: D A. 27& 27&.& .& . .( ( %. 17& 17&.& .&77 3 3(( C. 2751 2751.$ .$ 3 3(( '. 220" 220".1 .155 3 3( (
.
%ased %ased on the data data in probl problem em 4o. 5, what what is the mass mass flow rate rate of steam steam enteri enterin( n( the turbi turbine* ne* Answer: A
A. %. C. '. #.
". ". (3s (3s 7". ( (3s #". ( (3s 10". 0". (3 (3ss
%ase %asedd on the the data in prob proble lem m 4o. 5, what what is the the actual actual power power (ener (enerat ated ed b+ the plan plantt in @)* @)* Answer: A
A. %. C. '.
$7.50 @) @) 27.50 @) $5."0 @) 25."0 @) @)
10. %ased %ased on the data data in proble problem m 4o. 5, what what is the appare apparent nt power power develop developed ed b+ the (enerato (eneratorr in >A* Answer: D A. "$,5 "$,57& 7&.& .&7 7 A %. 51, 51,7" 7".& .&7 7 A A C. "5,2 "5,275 75.$ .$75 75 A A '. "&, "&,77 77." ."75 75 A 11. %ased %ased on the the data data in proble problem m 4o. 5, how how man+ m$3hr of fresh water that must be supplied to the main condenser if water from coolin( tower enters the condenser at $5 ºC and leaves at " ºC* Answer: A
A. %. C. '.
11,10 1,105. 5.$# $#$$ m$3hr 12,7 2,7"".&77 .&77 m$3hr 22,75 2,7511.$77 .$77 m$3hr 21,2 21,20" 0".1 .15 5 m$3hr
12. %ased on the the data in problem problem 4o. 5, how man+ produc production tion wells wells are needed needed to suppl+ suppl+ the plant plant with pressuriLed water if each well has a capacit+ of 127,200 (3hr* Answer: A A. 1$ we wells %. 1" wells C. 12 wells '. 10 we wells 1$. %ased %ased on the data in proble problem m 4o. 4o. 5, determin determinee the thermal thermal efficie efficienc+ nc+ of the (eother (eothermal mal plant* plant* Answer: D
A. %. C. '.
#.< #.57< .&#< 7.&<
1". ?n a (eothermal (eothermal power power plant, plant, the mass flow rate rate of (round water water is "00 (3s and and the ualit+ ualit+ after after throttlin( is 20<. ?f the turbine power is 0 @), what is the chan(e in enthalp+ of steam at the inlet and outlet of the turbine* Answer: A A. 1000 000 3( 3( %. 1500 3( C. 2000 3( '. 2500 500 3( 3(
15. /he mass mass flow rate of (round (round water in a 20 @) (eother (eothermal mal power power plant plant is 150 (3s (3s and its its enthalp+ is 1000 3(. if the ualit+ after throttlin( is 2< and the over=all plant efficienc+ is 20<, what is the mass flow rate of steam enterin( the turbine* Answer: A A. 2 (3s %. 7& (3s C. 1 (3s '. 2" (3s 1&. /he turbine turbine power power of a (eothermal (eothermal plant plant is 2 @) and the enthalp+ enthalp+ at the inlet inlet of the turbine turbine is 2500 3(. steam flows at the rate of 2.5 (3s. if the enthalp+ at the outlet of the condenser is $00 3( and the temperature rise of the coolin( water is 10 ºC, what is the volume flow rate of the coolin( water* Answer: C A. 10#.$7 m$3hr %. 2$7.& m$3hr C. 120.$7 m$3hr '. $20."7 m$3hr HYDROELECTRIC POWER PLANT
1. A h+draul h+draulic ic turbine turbine receives receives water water from a reservoir reservoir at an elevatio elevationn of 100 m above it. it. )hat is the minimum water flow in (3s to produce a stead+ turbine output of 50 @). @). Answer: B A. 50, 2"7 %. 50, #& C. 50, &72 '. 5#, "&5 2. A reaction reaction turbine turbine develops develops 500 500 %-!. %-!. Flow throu(h throu(h the turbine turbine is 50 cfs. )ater )ater enters enters at 20 fps with a 100 ft pressure head. /he elevation of the turbine above the tailwater level is 10 ft. find the effective head. Answer: D A. 1$0. 2 ft %. 120. 2 ft C. 110. 2 ft '. 11&. 2 ft $. A h+dro h+dro=elect =electric ric plant plant discha dischar(es r(es water water at the rate rate of 0.75 0.75 m $3s and enters the turbine at 0.$5 mps with a pressure of 275 !a. Eunner inside diameter is 550 mm, speed is 520 rpm and the turbine efficienc+ is <. Find the turbine speed factor. Answer: A A. 0. &$ %. 0. $& C. 0. $& '. 0. $& ". A h+dro=e h+dro=electr lectric ic plant plant havin( havin( 50 s m reservoir reservoir area area and 100 m dead dead head is used used to (enerate (enerate power. power. /he ener(+ utiliLed b+ the consumers whose load is connected to the power plant durin( a five hour period is 1$.5 8 10 & )=hr. /he over=all (eneration efficienc+ is 75<. Find the fall in the hei(ht of water in the reservoir after 5 hr period. Answer: B A. 2. 1$ m %. 1. $2 m C. $. 21 m '. 0. 5$ m
5. A !elton !elton wheel wheel is to be desi(ned desi(ned to run run at $00 rpm under under a effective effective head head of 150 m. /he /he ratio of the noLLle diameter of the pitch circle is 1312. Assumin( Assumin( efficienc+ of "<, what is the siLe in m. Assume a speed ratio of 0."5. Answer: C A. 1.05 %. 2.00 C. 1.55 '. 2.& &. "5 >) of the the shaft power power is develop developed ed b+ a turbine turbine worin( worin( under under availab available le head of of "0 m. /he ener(+ transferred from the water to the runner is $50 . Assumin( a mechanical efficienc+ of #5<, what is the dischar(e to the turbine in m $3s* Answer: B A. 0.0$"5 %. 0.1$5 C. 1.511 '. 1.2$" 7. A vertical vertical draft draft tube is instal installed led on a Francis Francis turbine turbine and the total total head to the the center of the spiral spiral casin( at the inlet is $ m and velocit+ of water at the inlet is 5 m3s. /he dischar(e is 2.1 m $3s. /he h+draulic efficienc+ is 0.7 and over=all efficienc+ is 0.". /he velocities at the inlet and e8it of the draft tube are 5 m3s and 1.5 m3s respectivel+. /he top of the draft tube is 1 m below the center line of the spiral casin( while the tailrace :water; level is $ m from the top of the draft tube. /here is no velocit+ of whirl at either top or bottom of draft tube and leaa(e losses are ne(li(ible. )hat is the power output of the turbine in >)* Answer: A A. 7". ) ) %. &$2.# ) C. #01.$ ) '. $2.& >w . A h+dro=el h+dro=electri ectricc (eneratin( (eneratin( station station is supplied supplied from a reservoir reservoir of capacit+ capacit+ &,000,000 &,000,000 m $ at a head of 170 m. Assume h+draulic efficienc+ of 0< and electrical efficienc+ of #0<. /he fall in the reservoir level after a load of 15 @) has been supplied for $ hrs, if the area of the reservoir is 2.5 m2 is closest to9 Answer: A A. 5.$# cm cm %. ".$2 cm C. 5.# cm '. ".$ cm cm #. An impulse impulse turbine turbine which which has has a diameter diameter,, ' &0 in. 6peed 6peed 4 $50 rpm, rpm, bucet bucet an(le an(le % 1&0 de(rees, coefficient of velocit+ C v 0.#, relative speed X "5, a (enerator e m 0.#0, 0.#0, and a et diameter from noLLle of & inches. Compute the power input in -p. Answer: A A. 2,& ,&2 -! %. 2,512 -! C. 2,#$$ -! '. 2,$& ,$&& -! 10. ?n @aria Christina Christina -+droelect -+droelectric ric !roect, !roect, the available available head is 1"0 m, the water flow is one m $ per second, efficienc+ of the turbine is #5<, efficienc+ of the (enerator is #5<, $=phase, &0 c+cles, volta(e delivered is "1&0 volts. 'etermine the estimated +earl+ income of the plant if cost of the (enerated electric ener(+ is ! 0.&0 per )=hr. Answer: A A. ! &,51 &,51", ",77 777. 7.0 0 %. ! 7,5 7,51" 1",7 ,777 77. .00
C. ! ,5 ,51" 1",7 ,777 77. .00 '. ! #,51 #,51", ",77 777. 7.0 0
11. )ater flows steadil+ with with a velocit+ of $.05 m3s in a horiLontal horiLontal pipe havin( a diameter of 15.2" cm. At one section of the pipe, the temperature and pressure of the water are 21 oC and &#.$ !a respectivel+. respectivel+. )hat is the friction factor* Answer: C A. 0.15& %. 0.00#1 C. 0.015 '. 0.71 12. A h+droelectric h+droelectric plant has a 20 @) @) (enerator with the the efficienc+ of #&<. #&<. /he (enerator is directl+ directl+ coupled to a vertical Francis t+pe h+draulic turbine havin( an efficienc+ of 0<. /he total (ross head on the turbine is 150 m while the loss of head due to friction is "< of the (ross head. /he runawa+ speed is not to e8ceed 750 rpm, determine the flow of water throu(h the turbine in cfs. Answer: C
A. %. C. '.
"0&.5# 505&."# &50.#" #"5.&0
1$. From From the hei(ht hei(ht of &5 m, water flows flows at the rate of 0.5 0.5 m $3s and is drivin( a water turbine connected to an electric (enerator revolvin( at 1&0 rpm. Calculate the power developed b+ the turbine b+ >) if the total resistin( torue due to friction is 5"0 4=m and the velocit+ of the water leavin( the turbine blades ".75 m3s. Answer: A A. 52$."2 %. 5"$.21 C. "5$.12 '. "$5.21 1". A !elton t+pe t+pe turbine was installed installed $0 m below the head (ate of the penstoc. penstoc. /he head loss due due to friction is 15< of the (iven elevation. /he len(th of the penstoc is 0 m and the coefficient of friction 0.000#$. 'etermine the power output in >). >). Answer: B A. 1",2# ",2#22.7" .7" %. 12,2#2.7" .7" C. 1#,2"2.7" .7" '. 17,"" 7,""22.#2 .#2 15. At a proposed proposed h+dro=ele h+dro=electric ctric plant plant site, the avera(e elevation elevation of the head of water is &00 mD the tailwater elevation is "0 m. /he avera(e annual water flow is determined to be eual to that volume flowin( throu(h a rectan(ular channel " m wide and 0.50 m deep and avera(e velocit+ of 5.5 m3s. Assumin( that the plant will operate $50 da+s per +ear, find the annual ener(+ in )=hr that the plant site can develop if the h+draulic turbine that will be used has a efficienc+ of 0< and (enerator efficienc+ of #2<. Consider a headwor loss of "< of the available head. Answer: B
A. &7,"5 7,"5,51 ,51 %. 7&,5 &,5"",51 ,51 C. 5",7 ",7&&,51 ,51
'. ",57 ,57&&,15 ,15
1&. A remote communit+ communit+ in @ountain !rovince !rovince plans to put a small h+droelectric h+droelectric plant to service service si8 closel+=located baran(a+s estimated to consume 52,&50,000 )=hrs per annum. 8pected flow of water is 1&&5 m $3min. /he most favourable location for the plant fi8es the tailwater level at "0 m. /he manufacturer of the turbine (enerator set have indicated the followin( performance data9 turbine efficienc+ 7<, (enerator efficienc+ #2<, loss in head wor not e8ceed $.< of available head. n order to pinpoint the most suitable area for the dam, determine the headwater elevation. Answer: A
A. %. C. '.
50.7& m &05.7 m 750.0 m 75.0& m
17. /he difference in elevation between the surface of the water in a stora(e reservoir reservoir and the intae to a turbine was 10" ft. durin( a test the pressure head at the latter point was 1$0 ft and the dischar(e was 150 cfs. /he inside diameter of the penstoc was $5 inches. )hat was the efficienc+ of the pipeline* Answer: B A. #0."< %. #$."< C. #1."< '. #2."< 1. ?n a h+draulic plant the difference difference in elevation between the the surface of the water at intae and the tailrace is &50 ft when the flow is #0 cfs, the friction loss in the penstoc is &5 ft and the head utiliLed b+ the turbine is 500 ft. /he mechanical friction in the turbine is 110 -p, and the leaa(e loss is " cfs. Find the h+draulic efficienc+. efficienc+. Answer: C A. 7."5< %. ".57< C. 5."7< '. 7.5"< 1#. /he difference in elevation elevation between the source of the water water suppl+ and the centreline centreline of the base of the noLLle of a pelton wheel is 1$00 ft. 'urin( the test the pressure at the end of the noLLle was 500 psi( when the flow is "5 cfs. ?nside diameter of penstoc is 25 in. Compute the water horsepower at the base of the noLLle. Answer: A A. 5#0". #0".7& 7& -p %. "50#.&7 -p -p C. 7"5#.&0 -p -p '. &#"5. #"5.70 70 -p 20. A !elton !elton wheel runs a constant constant speed under a head of of &50 ft. /he cross=sectional cross=sectional area of the et is is 2 0.50 ft and the noLLle friction loss is to be ne(lected. 6uppose that the needle of the noLLle is to be adusted as to reduce the area of the et from 0.50 ft 2 to 0.20 ft 2. nder these conditions the efficienc+ of the wheel is nown to be 70<. Find the power output of the wheel. Answer: A A. 2112.$ 12.$"" -p -p %. 250&.$" -p -p C. $017.&2 -p -p
'. $"&2. "&2.7" 7" -p
21. )ater flows flows at the the rate of 1.5 1.5 m$3s from a hei(ht of 100 m which drive turbine connected to a 150 rpm (enerator. 'etermine the turbine brae power if the frictional torue is &00 4=m. Answer: B A. 1&2. &2.02 02 ) %. 1"&2.0 ) ) C. 1&"2.0 ) ) '. 12&". 2&".0 0 ) 22. 22. /he /he mech mechan anic ical al volu volumet metri ricc and and tota totall effi effici cien enci cies es of a turb turbin inee are are #"<, #"<, #&< #&< and and 2< 2< respectivel+. Calculate the total head if the effective head is 50 m. Answer: A A. "5."$ m %. "".$5 m C. $5."" m '. 5$."" m 2$. A proposed proposed h+dro=electric h+dro=electric power plant plant has the followin( followin( data9 levation of normal headwater surface 1#" m levation of normal tailwater surface &0 m Joss of head due to friction &.5 m /urbine dischar(e at full (ate openin( 5 m $3s /urbine efficienc+ at rated capacit+ #0< /he turbine is to be connected to a &0 c+cle AC (enerator. Calculate the turbine braepower output. Answer: D
A. %. C. '.
&52.5 ) ) &52.5 ) 52&.5 ) 5&2.5 ) )
2". A h+dro=electric h+dro=electric power plant consumes &0,000,000 &0,000,000 >)=hr >)=hr per +ear. )hat is the net head if the $ e8pected flow is 1500 m 3min and over=all efficienc+ is &$<. Answer: C A. $".$" m %. "$."$ m C. "".$$ m '. $$."" m 25. A double double overhu overhun( n( impuls impulsee turbin turbinee of 5< efficie efficienc+ nc+ is direct direct connect connected ed to a $0,000 $0,000 ) (enerator of #$< efficienc+. levation of the headwater level is 27$0 ft above the sea level, elevation of tailwater is 12&0 ft above sea level, turbine settin( is 12 ft, velocit+ of flow in penstoc is eual to 0.025Y2(h, loss of head due to friction is 2< of (ross head. Compute the flow throu(h the turbine in cfs. Answer: A A. 157 ft$3s %. $1" ft$3s C. "1$ ft$3s '. 20&.5 ftft$3s
2&. ?n the test of a certain certain turbine the pressure pressure at the flan(e at the entrance entrance to the spiral=turbi spiral=turbine ne case where the diameter is $0 in. was read b+ a mercur+ manometer. At a flow of "" cfs the manometer differential readin( the =tube was #.5"1 ft -(, the top of the lower mercur+ column bein( #.7$ ft above the surface of the water in the tailrace, find the net head and the horsepower developed b+ the turbine. se turbine efficienc+ of #2<. Answer: A A. 1"0. 1"0.7$ 7$ ft, ft, &50 &50 -p %. 170. 170."$ "$ ft, ft, &50 &50 -p -p C. 1"0. 1"0.7$ 7$ ft, ft, 550 550 -p -p '. 170. 170."$ "$ ft, ft, 550 550 -p 27. Eiver Eiver flows flows at at $0 m $3s and develops a total brae power of 5 @). @). )hat is the available head if it is proposed to install two turbines with 5< efficienc+ each* Answer: A A. 1#.## m %. 25.2& m C. 1&.75 m '. 2$.1 m 2. /he total brae power developed developed b+ the two turbines is & @). @). )hat is the capacit+ of the smaller smaller unit if one unit is thrice the capacit+ of the other* Answer: A A. 1.5 @) %. 2.0 @) C. 2.5 @) '. $.0 @) 2#. /he over=all over=all efficienc+ efficienc+ of a 10 @) h+dro=electri h+dro=electricc plant plant is 5<. )hat is the secondar+ secondar+ power could this plant deliver if the actual power received b+ the costumer for that da+ is 100,000 w= hr* Answer: B A. 110,0 10,000 00 )=h )=hrs rs %. 10", 10",00 0000 )=h )=hrs rs C. 12", 12",00 0000 )=h )=hrs rs '. 1$0, 1$0,00 0000 )=h )=hrs rs $0. At a potential h+draulic=plant h+draulic=plant site the avera(e elevation elevation of the headwater is estimated at 112 112 ft, the tailwater elevation at 1575 ft. the avera(e annual water flow was determined to be eual to that volume flowin( throu(h a rectan(ular channel $0 ft wide with a " ft and an avera(e velocit+ of 15 ft3s. Find the annual electrical ener(+ this site can produce water with a water turbine efficienc+ of 5<, a (enerator efficienc+ of #5<, and the loss in the headwors eual to $< of the available head. Answer: B A. 1&0,"& 1&0,"&,0 ,000 00 )=hr )=hrss %. 2"7, 2"7,& &", ",00 0000 )=h )=hrs rs C. 2&0, 2&0,"& "&, ,00 0000 )=h )=hrs rs '. 1"7,& 1"7,&",0 ",000 00 )=hr )=hrss $1. A !elton !elton t+pe t+pe turbi turbine ne has a (ross (ross head of "0 m and a friction friction head head loss of & m. )hat is the penstoc diameter if the len(th is #0 m and the coefficient of friction head loss is 0.001 :@orse; Answer: A
A. 20"0 mm %. $120 mm
C. 2""0 mm '. 2$20 mm $2. /he water velocit+ of of a 5m 8 1m channel is & m3s. )hat )hat is the annual ener(+ ener(+ produced if the the net head is 120 m and the over=all efficienc+ is 0<. Answer: C A. "#", "#",2" 2"7, 7,25 25 w=hr w=hrss %. 2"7. 2"7."# "#7, 7,5 522 w=h w=hrs rs C. 2"7, 2"7,"# "#", ",52 52 w=h w=hrs rs '. "72, "72,"# "#7, 7,5 522 w=hr w=hrss $$. A 10,000 10,000 ) run=of=river h+dro=electric h+dro=electric plant has an available head of 200 ft and has has an over=all efficienc+ of #0< that remains constant for all loads. For a (iven da+ durin( the low water=steam season the costumer receivin( primar+ power have the followin( loads9 000 ) for 2 hrs "000 ) for 10 hrsfor 2 hr 2000 ) for 10 hrs For a river flow remainin( constant at 525 ft $3s, how much secondar+ power could this plant provide durin( the entire entire da+* Answer: A A. %. C. '.
10", 10",22 2200 )=h )=hrs rs 220, 220,10 10"" )=h )=hrs rs 20", 20",22 2200 )=h )=hrs rs 120, 120,10 10"" )=h )=hrs rs
$". Find the number of (enerator (enerator poles for a (enerator runnin( runnin( at &00 rpm and &0 -L. Answer: A A. 12 %. 2" C. & '. " $5. /he specific speed of the the turbine is 5 rpm rpm and runnin( at 500 rpm. rpm. )hat is the ma8imum ma8imum power delivered b+ the (enerator if the head is 25 m and (enerator efficienc+ is #0<. Answer: B A. 1,1"0 ,1"0.2 .211 ) ) %. 1,12 ,12.$ .$55 ) C. 2,11 ,11.$ .$55 ) '. 2,1"0 ,1"0.2 .277 ) ) $&. Calculate the power that that can be developed from from a h+dro=electric power power plant of station havin( the followin( data9 Catchment Area #0 m2 Avera(e Annual Eainfall 120 cm Eun=off 5< Available -ead $50 m ver=all 6tation 75< Answer: D
A. %. C. '.
7"&. 7"&.0& 0& ) &7#".0 ) ) #7"&.0 ) ) 7"#&. "#&.0 0 )
$7. ?n a h+droelec h+droelectric tric power plant, plant, the water surface surface on the crest of the dam is at elevation elevation 75.$ m while the water surface ust at the outlet of the head(ate is elevation 7"." m. /he head(ate has 5 (ates of $ft 8 $ ft leadin( to the penstoc and are full+ opened. Assume &1< as coefficient of dischar(e, determine the uantit+ of water that enters the h+draulic turbine per second. Answer: A
A. %. C. '.
"&".5 ftft$3s 5&"." ft$3s &"".5 ft$3s &5"." ftft$3s
$. A h+dro=e h+dro=elec lectri tricc impuls impulsee turbin turbinee is direct directl+ l+ couple coupledd to a 2" pole, &0 -L altern alternato atorr. ?t has a specific speed of &0 rpm and develops $000 -p. )hat is the reuired diameter assumin( a peripheral speed ratio of of 0."5 Answer: A A. 0.&&1 m %. 0.552 m C. 0.""$ m '. 0.775 m $#. ?n a h+droe h+droelec lectri tricc power power plant plant the tailwa tailwater ter elevati elevation on is at 500 m. )hat )hat is the head head water water elevation if the net head is $0 m and the head loss is 5< of the (ross head* Answer: C A. 75.25 m %. 52.57 m C. 52.57 m '. 75.25 m "0. A suppl+ suppl+ of water is available at a head of &0 m. it is proposed to build a turbine to operate at 125 rpm and this turbine is e8pected to develop 50 @). @). )hat is the critical speed Answer: A A. 1#$.7 #$.7## rpm rpm %. 1$#.7# .7# rp rpm C. $#1.#7 .#7 rp rpm '. $1#.# 1#.#77 rpm rpm "1. /he elevation of the the headwater is $250 ftft and that of the tailwater tailwater is &00 ft. ft. penstoc diameter is $ $0 in. water flowin( "0 ft 3s, turbine efficienc+ 5<, friction factor taen as 0.0$5, turbine settin( is ft above tailwater level. !enstoc len(th "000 ft. (enerator direct=connected to turbine has an efficienc+ of #2<. 4oLLle efficienc+ #&<. Compute the brae horsepower of the turbine Answer: A
A. %. C. '.
#15 -p #15 -p 51# -p #51 -p
"2. /he flow flow of water at 50 m elevatio elevationn is "5 m $3s. if a h+ro=electric plant is to be installed with turbine efficienc+ of 0< and (enerator efficienc+ of #2<, what is the ma8imum power that the plant could (enerate. (enerate. Answer: B A. 1".&25 @) @) %. 1&.2"5 @) C. 15.1"& @) '. 12."&5 @) @) "$. )hich of the followin( followin( choices choices is a suitable suitable (enerator (enerator speed for this t+pe of runner runner with the followin( data9 -orsepower 111,$00 4et head 0 ft lectrical efficienc+ 50 c+cles3s. Answer: A A. 5$.57 rp rpm %. 55.$7 rpm C. 57.5$ rpm '. 75.$5 rp rpm "". /he difference in elevation elevation between the source of the water water suppl+ and the centerline centerline of the base of the noLLle of a !elton wheel is 500 m. durin( a test run, the pressure at the base of the noLLle was $ @!a when the flow was 2.0 m $3s. !enstoc inside diameter is 0 cm. determine the brae power of the !elton wheel wheel if its efficienc+ is 5<. Answer: B A. $11."& 1."& ) %. 5,11 ,11$."& $."& ) C. ",11 ,115.$" 5.$" ) '. ",51 ",511. 1."$ "$ ) "5. /he pressure (a(e leadin( to to the turbine casin( of a Francis turbine turbine reads 0.5 @!a and the center of the spiral casin( is 5 m above the tail race. )hat is the net head velocit+ of water enterin( the turbine is am m3s* Answer: D A. &7.01 m %. 7&.01 m C. 70.&1 m '. &1.07 m "&. /he tailwater and the headwater of a h+dro=electric h+dro=electric plant are 150 m and 200 m respectivel+. respectivel+. )hat $ is the power if the flow is 15 m 3s and a head loss of 10< of the (ross head* Answer: A A. &,&21 ,&21.7 .755 ) ) %. 7,&21 ,&21.& .&55 ) C. 5,&21 ,&21.7 .7&& ) '. ",&21 ,&21.5 .5&& ) ) "7. )hat is the specific specific speed of a turbine in in a h+ro=electric plant plant if the net head is "0 ft, brae power is $ @) and runnin( at 500 rpm. Answer: A A. $15.2 15.200 rpm rpm %. 51$.02 .02 rp rpm C. 1$5.20 .20 rp rpm '. $51.2 51.200 rpm rpm
". A pelton pelton wheel in a h+dro=electric plant plant has an output of 17&00 17&00 %-! at $00 rpm under a head of of $ 510 m with 2# m 3s flow. flow. Calculate its critical speed. Answer: B A. &.2" rp rpm %. $.72 rpm C. 7.2$ rpm '. 2.7$ rp rpm "#. ?n a h+dro=electri h+dro=electricc plant, water water flows at 10 m3s in a penstoc penstoc of 1 m 2 cross= sectional area. ?f the net head of the plant is $0 m and the turbine efficienc+ is 5<, what is the turbine output* Answer: A
A. %. C. '.
2,501 ,501.5 .555 ) ) 2,100 ,100.2 .211 ) $,&2& ,&2&.$ .$"" ) $,12" ,12".& .&55 ) )
50. ?n a test of a reaction reaction turbine the water water flowin( over the weir in the tailrace tailrace was found to be $. $ $ ft 3s. the leaa(e into the tailrace was found to be 1 ft 3s. the elevation of the centerline of the shaft above the surface of the tailwater was 12.&7 ft. the diameter of the turbine intae was $0 in. and the pressure at this section was measured b+ a mercur+ =tube. /he readin(s in the two sides of the mercur+ =tube were 10.55& ft and 0.#00 ft, the Lero of the scale bein( at a level $.2 ft below that of the centerline of the turbine shaft. /he (enerator output was $#1. ), ), friction and winda(e loss 1$.),iron loss 2.0 ) and a mature loss of "." ). /he specific (ravit+ of the mercur+ used was 1$.57. calculate the efficienc+ of the turbine. Answer: A A. &".&7< %. 5".&7< C. 75.57< '. &7.&"< 51. A tan contains water. water. )hat is the intensit+ intensit+ of pressure at a depth of & m* Answer: B A. &.0 ! !A %. 5. !a C. 7.0 !a '. ".7 ! !a 52. Convert water pressure of 50 50 !Aa !Aa in euivalent meter head head of water. water. Answer: A A. 5.1 %. &.1 C. 7.1 '. ".1 5$. )hat is the over=all over=all efficienc+ efficienc+ of the turbine if the power developed developed is 15,000 ) at a head of $ 170 meters and the noLLle dischar(e is 10 m a second* Answer: B A. 70.0#$< %. #.#0< C. 7#.##< '. #0.0#&<
NON-CONVENTIONAL POWER PLANT
1. A solar solar collec collecti tin( n( panel panel 20m 20m 2 in area receives solar ener(+ at the rate of 750 )3m 2. ?t is estimated that $5< of the incident ener(+ is lost to surroundin(9 water enters the panel at stead+ flow rate of 0.05(3s at 15PC. Calculate the temperature of water leavin( the collectin( panel. Chan(e in elevation of water is 2m. Answer: A A. &1.5&PC %. "5.7&PC C. 5"."5PC '. 71."5PC 2. An American t+pe wind mill with an aerod+namic efficienc+ of 10< is wanted to pump $liters3 $li ters3min min from well to a tan loca located ted at 1.$ 1.$m m above the water surface of the well when the wind has a velocit+ of $0ph. Consider that frictional losses of the s+stem divert $0< of the ener(+ received b+ the wheel. )hat well diameter is needed* Answer: A A. 2.5 m %. $." m C. 1.5 m '. 1.7 m $. /he sun (enerates an avera(e of 2)3m 2 when tapped as source of ener(+ where in a flat plate collector with an area of 1.5m 2 is used. Flow rate of water inside the collector is "0liter3hr. calculate for the temperature rise of the worin( fluid in PC. Answer: A A. &5.1"PC %. &0.15PC C. 55.1"PC '. 50.15PC ". A windmill with a &m radius rotor is to be installed where atmospheric pressure conditions prevail at 101.$25!a and 21PC. it was observed that wind is blowin( steadil+ at an avera(e velocit+ of 20m3s. Assumin( that the conversion efficienc+ is somewhere between 20=25<, determine the ma8imum available power from the windmill. Answer: B A. 12".7 .7) %. 1$5. .11) C. 1&7.2 .255) '. 225.7 .7) NUCLEAR POWER PLANT
1. A nuclear power plant is to have a capacit+ of 500@)=electrical. -ow man+ lbs of 2$5 are needed to operate the plant continuousl+ for &+rs if the plant capacit+ factor is 75< and thermal efficienc+ $5<. Answer A A. 517#.05 %. 5$75.01 C. &"2&.25 '. &77.&"
2. )hen a 2$5 nucleus fissions, about 250mev of ener(+ are release. )hat fraction of the wei(ht of the nucleus is thereb+ converted into ener(+* Answer: B A. 2.2& 8 10=$ %. 1.1$ 8 10=$ C. 1.51 8 10=$ '. 2.52 8 10=$ $. A &00 @) !)E nuclear plant uses "< enriched uranium fuel is a thermal efficienc+ of $&<. /he burn up allowed of the fissionable portion of the fuel is 20<. Calculate how man+ metric tons of natural uranium is placed in the reactor vessel for 1+r continuous operation* Answer: B A. &#.$" %. 7#.$5 C. .5& '. 5&.77 ". 'etermine the wavelen(th of (amma photon havin( an ener(+ of 1@ 1@.. Answer: C =10 A. 1.5$ 8 10 cm %. 2.2 8 10=10cm C. 1.2" 8 10=10cm '. $.0& 8 10=10cm 5. A nuclear power plant has a rated capacit+ of 200@) electrical power. /he core contains 50tons of uranium enriched to 2< 2$5. 'etermine the avera(e thermal neutron flu8 in the reactor reuired at rated plant capacit+. Answer: D A. 1.1 8 101$ neutrons3cm2=s %. 1." 8 101$ neutrons3cm2=s C. 1.2 8 101$ neutrons3cm 2=s '. 1.$ 8 101$ neutrons3cm 2=s &. A proton has a inetic ener(+ of 10 @ev. )hat is its velocit+* Answer: C A. ".$" 8 1010 m3s %. $.$" 8 1010m3s C. ".$" 8 1010cm3s '. $.$" 8 10 10cm3s 7. )hat is the wavelen(th of the most ener(etic 8=ra+s from a 150,000 volt tube* Answer: A A. .275 8 10=10cm %. .275 8 10=10cm C. 7.25 8 10=10cm '. 7.52 8 10=10cm . ?f all the e8act isotopic mass of -e " is ".0017 amu, calculate the total bindin( ener(+ and the bindin( ener(+ ener(+ per nucleon. Answer: B A. $0. $0.1" 1" @ev, @ev, .5$@ev3 .5$@ev3nu nucle cleon on %. $0. $0.1" 1" @ev @ev,, 7.5$@e 7.5$@ev3n v3nuc ucleo leonn C. $5. $5."1 "1 @ev @ev,, 7.5$@e 7.5$@ev3n v3nuc ucleo leonn '. $5. $5."1 "1 @ev, @ev, .5$@ev .5$@ev3nu 3nucle cleon on
MACHINE FOUNDA FOUNDATION TION
1. )hat is the reuired base area of the foundation to support an en(ine with specified speed of 1200 rpm and wei(ht of #000(. assume a safe bearin( capacit+ of soil as "7.&7!a. use c0.11. Answer: B
A. %. C. '.
5.57m2 .7m2 7.75m2 10.5m2
2. A 1929$ mi8 of concrete with & (allons of water per ba( cement is bein( prepared. 'etermine the wei(ht of 1 ft $ of finished concrete of this mi8ture. /he materials to used have the followin( characteristics9 1 ba( cement :1ft$; wei(hs #" lbs $ 1 ft sand wei(hs 105 lbs $ 1 ft of stone wei(hs 105 lbs 6pecific (ravit+ of cement $.1 6pecific (ravit+ of sand 2.7 6pecific (ravit+ of broen stone 2.7 Answer: D
A. %. C. '.
1&" lbs3ft$ 172 lbs3ft$ 1&2 lbs3ft$ 152 lbs3ft$
$. )hat is the len(th of the machine m achine foundation if the len(th of the bedplate is "m* Answer: A A. ".m %. 5.5m C. $.$m '. &.&m ". ?f the width of the bedplate is $m and the clearance is 0.$ what is the upper width of the machine foundation* Answer: C A. 5.5m %. ".$m C. $.$m '. 5.5m 5. )hat is the appro8imate wei(ht of the en(ine if the wei(ht of the machine foundation is $5000 (* Answer: C A. 570 ( %. 5750 ( C. 570 ( '. 750 ( &. Calculate the cu. +ard of stone reuired for a concrete mi8ture of 1929" of a foundation with dimension "m 8 5m 8 &m* Answer: B A. 12#.&1 +ard$ %. 1$.1" +ard$ C. 15&.2 +ard$ '. 1&7.## +ard$
7. ?f the volume of the foundation is 5cu. ft and the densit+ of concrete is 1&0 lbs3cu.ft what is the total wei(ht* Answer: C A. &00lbs %. 700lbs C. 00lbs '. #00lbs . /he bedplate dimension of a rectan(ular foundation cross=section is 2m 8 12m. the hei(ht of foundation and the uniform clearance of each are one meter and 0.50m respectivel+. Find the wei(ht of steel bars if the wei(ht of the steel bar reinforcements needed is Z< of the wei(ht of the foundation. 4ote9 use densit+ of concrete euals 2"0&(3m $. Answer: A A. 70$.7 .755( %. 0&.1 .100( C. &"".5 .5""( '. 50#.# .#22( #. !iles are driven in a uicsand :%earin( 5tons3m 2; on #00mm centers. /he+ are driven until the penetration under the last hammer blow is 25mm. the concrete slab #00mm thic. )hat is the avera(e bearin( power in tons per m 2 does this foundation provide* Answer: B A. 12.1 %. 10.& C. 11."1 '. 1$.77 CHIMNEY
1. A steam boiler plant consumes #000 ( of coal per hr and produces 20 ( of dr+ flue (asses per ( of coal fired. utside air temperature $2PC, avera(e temperature of the flue (as enterin( the chimne+ is $"$PC and the avera(e temperature of dr+ flue (as of the chimne+ is 2&0PC. /he (a(e fluid densit+ is ##".7 (3m 2 and the theoretical draft of 2.2&cm of water at the chimne+ base is needed when the barometric pressure is 7&0mm -(. 'etermine the hei(ht of the chimne+* Answer: C
A. %. C. '.
$0 "0 50 &0
2. ?f the actual draft for a furnace is &.2$# cm of water the frictional losses of the stac are 15< of the theoretical draft, calculate the reuired stac hei(ht in meters. Assume that the flue (as have an avera(e temperature of 1"#PC and molecular wei(ht of $0. Assume air temperature of 21PC. Answer: C
A. %. C. '.
215 2$0 220 210
$. A steam (enerator with economiLer and air heater has an overall draft loss of 21.7cm of water. ?f the stac (asses are at 177PC and if the atmosphere is at 101.$!a and 2&PC. what is the theoretical hei(ht of the stac in meter is needed when no draft fans are used* Assume that the (as constant for the flue (asses is the same as that for air. Answer: D A. 5&5 %. 5$5 C. 5"5 '. 550 ". A coal fired steam boiler uses $000 ( of coal per hour. Air reuired for combustion is 15.5 ( per ( coal at barometric pressure of #.2 !a. /he flue (as has a temperature of 25PC and an avera(e molecular wei(ht of $0. Assumin( an ash loss of 11< and allowable (as velocit+ of 7.5m3s, find the diameter of the chimne+ chimne+.. Answer: A A. 1.#1 m %. 1.2 m C. 2.&2 m '. 2.#$ m 5. /he over=all draft loss of steam (eneratin( unit is "00 mm water. Air enters at 101.$25!a, 2&PC and the avera(e flue (as temperature is found to be 250PC. if no draft fans are to be installed, what is the hei(ht of the chimne+* Assume Assume E(0.2273(=>. Answer: A A. $1.&0 m %. 722.5 m C. #2&.&5 m '. 5##.1 .111 m &. )hat is the hei(ht of the chimne+ if the drivin( pressure is $0 !a and the (as and air densities are 1(3m$ and 1.5 (3m$ respectivel+* Answer: C A. 50.2 m %. 71.1& m C. &1.1& m '. 0.22 m 7. ?f the air reuired for combustion is 20 ( per ( of coal and the boiler uses $000 ( of coal per hr, determine the mass of (as enterin( the chimne+. Assume Assume an ash loss of 15<. Answer: C A. "0& 0&"" ""( (3h 3hr r %. 702 0200 00( (3h 3hr r C. &25 2550 50( (3h 3hr r '. 505 0500 00( (3h 3hr r . A 15 ( (as enters a chimne+ at 10m3s. if the temperature and pressure of a (as are 2&PC and 100 !a respectivel+, respectivel+, what is the diameter of the chimne+. se E0.273(=>. Answer: D A. 1.57 m %. 2.&5 m C. 2.22 m '. 1.2 m
#. A $#.5 m hi(h chimne+ of radial bric masonr+ is described b+ the followin( top and bottom dimensions. '2 1.#m, d2 1.5m, '1 $.2m, d1 2.$m. 'etermine the moment due to wind load. Answer: D A. 172 7205 0511 (=m (=m %. 1&0 &0$$ $$ ( (=m C. 150 501& 1&00 ( (=m '. 12 20$ 0$00 (=m (=m 10. ?n a steam power plant, 5 ( of coal is consumed per second and it was late found that 25 ( of dr+ flue (as is produced per ( of coal fired. Air enters at 25PC. /he avera(e temperature of the flue (as enterin( the chimne+ is 250PC. A theoretical draft of 5 cm of water at the base of the chimne+ is needed. /he (a(e fluid specific volume is 0.0025 m $3(. ?f the molecular wei(ht of the (as is 20, calculate the hei(ht of chimne+. chimne+. Answer: A A. "1.15 m %. $&.27 m C. 52.& m '. 55."2 m 11. A power plant is situated at an altitude havin( an ambient air at #&.5$!a and 2$.PC. Flue (ases at a rate of 5(3s enters the stac at 200PC and leaves at 1&0PC. /he flow (ases (ravimetric anal+sis are 1< C 2, 7< 2, and 75< 42. 4ote9 /he actual velocit+ is "0< of the theoretical velocit+. Answer: C A. 0.75 m %. 0.5 m C. 0.#5 m '. 1.15 m VARIABLE LOAD PROBLEMS
1. A central station is suppl+in( ener(+ to a communit+ throu(h two sub=stations. ne substation feeds four distributin( circuitsD the other is si8. /he ma8imum dail+ recorded demands are9 !)E 6/A/?4 12000 ) 6ubstation A &000 ) Feeder 1 1700 ) Feeder 2 100 ) Feeder $ 200 ) Feeder " &00 ) 6ubstation % #000 ) Feeder 1 &20 ) Feeder 2 1500 ) Feeder $ 1000 ) Feeder " 2#00 ) Feeder 5 2200 ) Feeder & $$00 ) Calculate the diversit+ factor between substations, between feeders on 6ubstation A and between feeders on 6ubstation %. Answer: A A. 1. 1.25 25,, 1.1 1.15, 5, 1. 1.25 25 %. 1. 1.$& $&.. 1.2 1.21, 1, 1. 1.$& $& C. 1. 1.2 2,, 1.1 1.1#, #, 1. 1.$2 $2 '. 1. 1.$2 $2,, 1.1 1.17. 7. 1. 1.$5 $5
2. A 75 @) power plant has an avera(e load of $5000) and a load factor of &5<. Find the reserve over pea. Answer: A A. 21.25 @) @) %. 2$."1 @) C. 25.$ @) '. 1.75 @) @) $. /he annual pea load on a 15000 ) power plant is 10500). /wo substation are supplied b+ this plant. Annual ener(+ dispatched thou(h substation A is 27,500,000 )=hr )=hr with a pea load at #00 ), 1&,500,000 are sent throu(h substation % with a pea load at &&50). 4e(lect line losses. Find the diversit+ factor between substation and capacit+ factor of the power plant. Answer: B
A. %. C. '.
1." .", 0." 0.""& "& 1." .", 0.$ .$$5 $5 1.7 .755, 0.$ .$$5 $5 1.7 .755, 0." 0.""& "&
". )hat is the dail+ avera(e load in a certain power plant if the dail+ ener(+ produced is 500,000 )=hr. Answer: D A. 2.2# ) ) %. $0.2& ) C. 1#.&1 ) '. 20.$ ) ) 5. A distributin( transformers supplies a (roup of (eneral power customers havin( a connected load of 1&). 'emand factor and diversit+ factor are 0.75 and 1.5 respectivel+. ?f the load factor for the (roup will avera(e of "5< and the ener(+ sells $.5 cents per )=hr, )=hr, what will be the monthl+ income inc ome :$0 :$0=da =da+; +; fro from m ene ener(+ r(+ del delive ivered red th throu rou(h (h thi thiss tra transf nsform ormer* er* Ass Assume ume ene ener(+ r(+ mot motor or efficienc+ is 75<. Answer: A A. ! 1" 1"0& 0&.1 .1&& %. ! 212.$2 C. ! 1502.&1 '. ! $0 $00$ 0$.2 .222 &. )hat is the annual capacit+ factor of the plant if the annul ener(+ produced in a 150@) power plant is 500,000,000 ) )=hrs* =hrs* Answer: A A. $.05< %. "".0"< C. 5&.75< '. $".""< 7. A power plant is said to have3had a use factor of ".5< and a capacit+ factor of "2."<. -ow an+ hours did it operate durin( the +ear* Answer: B A. &&0 &00. 0.$2 $2 hr hrss %. 7&5 &5. .2$ 2$ hr hrss C. &0 &00. 0.$2 $2 hr hrss '. 5&5 &5. .2$ 2$ hr hrss
. A central station has an annual factors as follows9 Joad factor 5.5<, capacit+ factor "0.#0<, use factor "5.2<. /he reversed carried over and above the pea load is #00 ). Find the no. of hrs per +ear not in service. Answer: A A. $$ $$.$ .$77 hrs %. 7$$.$ .$ hr hrs C. 7$.$ .$$$ hr hrs '. 7$ 7$.$ .$$$ hrs #. A 50,000 ) steam plant delivers an annual output of 2$,000,000 )=hr with a pea load of "2,&0).. )hat is the annual load factor and capacit+ factor* Answer: C "2,&0) A. 0. 0.&$ &$", ", 0. 0.5$ 5$"" %. 0.& .&"$ "$,, 0.5 0.5$$" C. 0.& .&$" $",, 0.5 0.5""$ '. 0. 0.&" &"$, $, 0. 0.5" 5"$$ 10. Calculate the use factor of a power plant is the capacit+ factor is $5< ad it operates 000 hrs durin( the +ear* Answer: A A. $.$25< %. $$.25< C. $5.$2< '. $5.5$< 11. Iiven a load factor, 0.", installed capacit+, $5000 ), reverse over pea $000 ), hours out of service per +ear "10. Find the capacit+ and the use factor. Answer: A A. " ".$ .$#< #<,, "&.0 "&.0"< "< %. "$ "$. .#< #<,, "". "".0& 0&< < C. "$ "$. .#< #<,, "&. "&.0" 0"< < '. " ".$ .$#< #<,, "".0 "".0&< &<
12. /he s+stem shown in the fi(ure consists in part of transformer servin( costumers [, \, ]. stimate the pea load on the transformer. [ G store buildin( with 5) li(htnin(, 25) small motor power \ G store buildin( with 1) li(htnin(, $5) small motor m otor power ] G store buildin( with 55) li(htnin(, 0) lar(e motor power 'istribution /ransformer
[
\
]
Ji(htin( 5 ) @otor 25 )
Ji(htin( 1 ) @otor $5 )
Ji(htin( 55) @otor 0 )
Answer: B
A. %. C. '.
75.0) 5.07) #5.") 105.7 .7&&)
1$. A dail+ load curve which e8hibited a 15 minute pea of 150,000) is drawn to scales of 1 cm $hrs and 1 cm 10000). /he area under the curve is measured b+ a planimeter and fund to be &0 cm2. )hat is the load factor based on the 15 minute pea* Answer: A A. 0.50 %. 0.75 C. 0.55 '. 0.&5 1". A distributin( transformer supplies a (roup of (eneral power costumers havin( a connected load of 200). ?f the demand and diversit+ factor are 0.75 and 1.5 respectivel+. Calculate the ma8imum simultaneous demands. Answer: C A. 150 ) %. 2"0 ) C. 100 ) '. 200 ) 15. ?f the rated capacit+ of the s+stem is 50,000 ) and the actual ma8imum demand is $5,000 ), what is the utiliLation factor* Answer: B A. 0.&0 %. 0.70 C. 0.50 '. 0.0
PIPING SYSTEM
1. )ater flows steadil+ with a velocit+ of $.05m3s in a horiLontal pipe havin( a diameter of 15.2" cm. At one section of the pipe, the temperature and pressure of the water are 21PC and &#.1$!a, respectivel+. At a distance of $5".m downstream, the pressure is 51&.#!a. )hat is the friction factor* Answer: C A. 0.1$" %. 0.005 C. 0.01# '. 0.&"1 2. Find the (3m 2 fiction loss in a $0.5 m copper pipe, 1#.1 mm ?.'. in which there is a flow of 5"" (3hr of 2"P%e fuel oil at 21.1PC. Answer: A A. 0.&$5 (3cm2 %. 0.$&5 (3cm2 C. 0.5&$ (3cm2 '. 0.5$& (3cm2 $. A certain 1.$0 m section of insulated 2$" mm schedule 0 steel pipe when warmed to operatin( temperature from a cold state of "."PC produces initial condensation which a trap should drain out as the line heats up. Assume this taes 5minutes. 6team saturated at 2.1(3cm 2 (a(e. stimate the dischar(e capacit+ of the trap in (3hr (3hr.. /he pipe wei(hs #&.0"(3m. Answer: B A. 21 2152 52.$ .$"" (3 (3hr hr %. 11# 1#&. &.52 52 ( (3h 3hr r C. 21 21#& #&.5 .522 ( (3h 3hr r '. 115 152. 2.$" $" (3 (3hr hr ". )hat is the worin( stress of a schedule 120 pipe with the followin( data9 utside diameter 21#.0mm )all thicness 1.2" mm )orin( pressure 17.&0(3cm 2 (a(e Allowance corrosion 1.&5 Answer: A
A. %. C. '.
10#.17 (3cm 2 1#0.17 (3cm 2 1&0.$# (3cm 2 1"0.$# (3cm 2
5. A 25"mm schedule 0 A=5$ steel pipe is clamped between two ri(id supports &.1 apart when its temperature is 15.&0PC. a liuid at #$.$PC is then pumped throu(h the line. )hat is the area of the material under stress* /he outside diameter and the wall thicness of the pipe are 27$.05mm and 15.0& mm respectivel+. Answer: D A. 0.1&50 m2 %. 0.01&5 m2 C. 0.1220 m2 '. 0.0122 m2
@iscellaneous @ %oard !roblems &. /he over=all efficienc+ of an electric s+stem, coal pile to li(hts, is 11<. )hat is the fraction of a ( of coal containin( $0250 3( must be consumed to li(ht a 100) lamp for "5 minutes* Answer: C
A. %. C. '.
0.7 ( 0.0#5 ( 0.01 ( 0.0&5 ( (
7. A power plant serves a factor+ havin( two 22 ) motors and ten $.7 ) motors. Assume the efficienc+ of motors 0<, of transmission line #5<, of (enerator #2<. )hat should be the rated capacit+ of the en(ine* Answer: A A. 115. 5.5 5 ) %. 200.7 .755 ) C. 2"5.5 .5&& ) '. "57.$ .$55 ) ) . An electric motor converted 700 ) of electrical input into wor at 5.1& (=m3s. /he speed was 1750rpm. Find the (=m of driven torue. Answer: C A. 0.1 .1$ $ ( (=m =m %. 0.$ .$2 ( (=m C. 0.$ .$11 ( (=m '. 0.1 .1$ $ ( (=m =m #. ?n a char(e over from steam to electric heatin(, a unit which had been considerin( ".5 ( dr+ and saturated steam at 2.10# (3cm 2 absolute each 15 min is to be electricall+ heated from 220 circuit. -ow man+ 12 ohm resistor in parallel would be needed to suppl+ the same heat* Jatent heat of vaporiLation at 2.10# (3cm 2 is 21#.5$5 3(. Answer: C A. $ %. 2 C. " '. 5 10. An electric heater is to heat 11 ( of oil per minute from ".5PC to &5.5PC. 6pecific heat of the oil is 2.1 3(PC. -ow man+ watts should this heater consume* Answer: B A. 2".$5 ) ) %. 2$."5 ) C. 2.$5 ) '. $2.5" ) ) 11. /he flow of a river is ".25m $3s at a site where a 22.&m h+drostatic head can be created b+ the erection of the dam. )hat is the potential capacit+ of the h+dro=electric power plant if installed at this site* Consider that the h+draulic efficienc+ of ener(+ conversion can be 0<, and that the electric efficienc+ can be #0<. Answer: B A. && &&.5 .522 22 ) %. &&.2 .2225 ) ) C. 5&&. .222 ) ) '. &5& 5&.5 .522 22 )
12. A hoist is to raise 111"7.727 4 mine ca(e at the rate of ".57 m3s. @echanical efficienc+ of the hoist #2<. )hat is the ) reuired to drive at this speed* Answer: C A. 7$.5 .5$$$ ) ) %. 7$.$ .$$$5 ) C. 55.$ .$775 ) '. 5$.$ .$775 ) ) 1$. A turbo (enerator rotatin( mass has a moment of inertia of 555 h+ls3m 2. ?t is deliverin( 2500 ) at 100rpm. /he load then suddenl+ increased to 2550 ) ),, the developed steam power remainin( unchan(ed. )hat is the resultin( speed in rpm in 10 seconds* Answer: A A. 17 177. 7.2 rp rpm m %. 12.7 .777 rp rpm C. 12.7 .777 rp rpm '. 21 217. 7.7 rp rpm m 1". Fort+ percent of the electrical input to a motor driven pump is converted into a h+draulic et 0.01$m in diameter for the purpose of wastin( down ashes. Find the het velocit+ inm3s. /he motor has a $=phase,220 , , 7.5 amp ratin(. !ower factor 5<. Answer: A A. 52.$ .$ m3 m3s %. 5.$ .$22 m3s C. $.5 .522 m3s '. $5. .$$ m3 m3s 15. /he difference in tension between the sides if a belt burnin( over a 0.7&2m diameter pulle+ is 22.727 (. !ulle+ speed is 500 rpm. )hat is ) transmitted* Answer: A A. "."5 ) ) %. $."5 ) C. $.5" ) '. &."" ) ) 1&. )hat is the power of the steam et 0.015 m in diameter movin( at 7&1.#&2 m3s* 6team condition, 1."0& (3cm2 dr+ and saturated :v 1 0.1#m$3(;. Answer: C A. 220.2 .277) %. 202.7 .7) C. 20.7 .722) '. 20.2 .277) 17. A pump is liftin( water throu(h 5."& m to fill a 5&&.25" m $ tan. /he over=all ener(+ efficienc+ is 0<. Calculate the len(th of time that 7."& ) applied to the pump will reuire to complete the ob. Answer: B A. 5 5.1 .111 mi minn %. 1.5 .511 min C. 75.1 .111 mi min '. 71.5 .511 mi min
