Thermal Radiation Study Bench Caleb Tee Li Jun 0318976 School of Engineering Taylor’s Uniersi!y 17 Se"!e#ber $01% *rou" 'e#bers +g ,ui ,ui Loong Lee 'an Chee -alaichelan ./L .ruga# Shiani .#ish .#ish -u#ar )an(ya Date of Experiment: Report due date: Report submission date: Checked by:
Table of Content Content ABSTRACT 1.0 INTRODCTION !.0 "#$"RI%"NTA& "# $"RI%"NTA& D"SI'N
Item/marks Format/10 Abstract and Introduction/10 Fiures and 3 Diarams/1! "ateria#s and "ethod/10 3 Resu#ts Discussions/$! References/10 %ota# %ota#
$&1 'a!erials
(
$&$ 'e!ho(s
)
$&3 )roce(ures
)*+
1
3.0 R"S&T AND DISCSSION
3&1 a!a Tabula!ion
,
3&$ *ra"hs
-
3&3 Calcula!ion 3&% iscussion
10
(.0 "RROR ANA&/SIS
11
).0 CONC&SION
1!
+.0 R""R"NC"S
1!
Abtract This e"eri#en! is (one in !2o "ar!s 2hich is e"eri#en! . an( e"eri#en! & uring e"eri#en! .4 !he "o2er 2e use is cons!an! 2hile !he one 2hich is changing is !he (is!ance of !he ra(io#e!er an( !he hea! source& 5hile4 in e"eri#en! 4 !he (is!ance of !he ra(io#e!er an( !he hea! source is cons!an! bu! !he "o2er is changing !o #ini#u#4 #e(iu# an( #ai#u# "o2er& ro# e"eri#en! .4 resul! sho2s !ha! !he in!ensi!y of !he ra(io#e!er is inersely "ro"or!ional !o !he (is!ance of !he ra(io#e!er an( !he hea! source& This sho2s !ha! !he (is!ance affec! !he rea(ing of !he in!ensi!y of !he ra(io#e!er& n e"eri#en! 4 2e can see !ha! !he in!ensi!y of !he ra(io#e!er increases as !he "o2er increase !ha! #aes !he !e#"era!ure increase& This sho2s !ha! !he "o2er !ha! con!rol !he
$
!e#"era!ure affec!s !he in!ensi!y of !he ra(io#e!er& n !his e"eri#en!4 bo!h ran(o# error an( sys!e#a!ic error occurs as !he resul! is sligh!ly (ifferen! fro# !he !heore!ical alue& u! s!ill4 S!efanol!:#ann la2 has been "roen !rue in !his e"eri#en!&
1.0 Introduction The #ain ob;ec!ie in con(uc!ing !his e"eri#en! is !o "roe !ha! !he in!ensi!y of !he ra(io#e!er is inersely "ro"or!ional !o !he (is!ance be!2een !he ra(io#e!er an( !he n(
hea! source& or !he $
e"eri#en!4 i! "roes !ha! !he in!ensi!y of !he ra(ia!ion is also
affec! by !he "o2er of !he hea! source 2hich is !he !e#"era!ure& Ther#al ra(ia!ion is (ifferen! fro# con(uc!ion an( conec!ion4 !her#al ra(ia!ion re
q b
=
[T
σ
%
S
−
T A% ]
2here4
= Energy e#i!!e( by uni! area of a blac bo(y surface >5#$?
@
= S!efanol!:#ann cons!an! e
5#$-%?
TS
= Te#"era!ure of blac "la!e >-?
T.
= Te#"era!ure of !he ra(io#e!er an( surroun(ings >-?
!.0 "2erimental Dei4n
!.1 %aterial
3
iagra# 1& Ther#al a(ia!ion a""ara!us
. )o2er con!rol a(io#e!er rea(ing C Dea! source a(io#e!er E F+’ s2i!ch Te#"era!ure rea(ing
1? Ther#al a(ia!ion .""ara!us > .4 4 C4 4 E4 ? $? )ro!ec!ie coer 3? lac "la!e
!.! %ethod
%
. !her#al ra(ia!ion a""ara!us is "lace( on a fla! !able& The s2i!ch us !urne( !o F+’ bu!!on as !he !e#"era!ure increase as sho2n on !he !e#"era!ure rea(ing& .s !i#e goes by4 !he rea(ing of !he !e#"era!ure 2ill be s!abili:e( a! a cer!ain a#oun!& The ra(io#e!er rea(ing is also obsere( by us as !he !e#"era!ure increases& The ra(io#e!er is coere( by a rubber coer !o "reen! !he hea!ing of !he ra(io#e!er& is!ance of !he ra(io#e!er an( !he hea! source is by a scale on !he !rac& The #easure#en! of !he (is!ance is use( using "arallel !o !he eyes leel !o aoi( "aralla error& To aoi( !he inaccuracy of !he ra(io#e!er rea(ing4 !he e"eri#en! is s!ar! fro# !he fur!hes! !o !he neares! be!2een !he ra(io#e!er an( !he hea! source&
!.3 $rocedure
"2eriment A5 In6ere S7uare &a8 of 9eat
1& 'ain s2i!che( is !urne( F+’ !o enable !he "o2er !o flo2 in!o !he a""ara!us& $& The ra(io#e!er is coere( 2i!h a rubber "ro!ec!or& 3& The "o2er con!rol is se! !o !he #i( "osi!ion as cons!an! !o con(uc! !he 2hole e"eri#en!& %& .s !i#e goes by4 !he !e#"era!ure is se! !o a s!able s!a!e before no!icing !he ra(io#e!er rea(ing& A& The ra(io#e!er is "lace( a2ay fro# !he hea! source 2i!hin A00##4 %00##4 300##4 $00## an( 100## res"ec!iely& 6& .s !he !e#"era!ure is s!abili:e(4 !he rubber coer an( !he blac "la!e is !aen off !o con(uc! !he e"eri#en!& 7& a(io#e!er rea(ing !hen is recor(e( an( is 2ri!!en in!o !he !able "re"are(& 8& The e"eri#en! is #a(e res"ec!iely by changing !he (is!ance of !he ra(io#e!er an( !he hea! source& 9& esul!s is !aen an( recor(e( in !he !able "re"are(&
"2eriment B5 Stefan:Bolt;mann &a8
A
1& $& 3& %&
'ain s2i!che( is !urne( F+’ !o enable !he "o2er !o flo2 in!o !he a""ara!us& The ra(io#e!er is coere( by a rubber "ro!ec!or& The "o2er con!rol is se! !o !he #ini#u# !o con(uc! !he 1s! "ar! of !he e"eri#en! .s !i#es goes by4 !he !e#"era!ure sho2n on !he !e#"era!ure rea(ing is !hen
s!abili:e(& A& The (is!ance of !he blac "la!e an( !he hea! source is A0## an( i! s!ays cons!an!& 6& The rubber coer an( !he blac "la!e is !hen !aen off af!er !he !e#"era!ure is s!abili:e(& 7& The resul!s sho2n on !he ra(io#e!er rea(ing is !hen recor(e( in !he !able& 8& E"eri#en! is re"ea!e(ly (one by changing !he "o2er !o !he #ini#u#4 #e(iu# an( #ai#u#& 9& esul!s sho2n in !he e"eri#en! is !aen an( !abula!e(&
3.0 Reult and Dicuion 3.1 Data Tabulation
E"eri#en! .G
6
Table 15 Radiometer Readin4* R and Ditance from the 9eat Source* #
is!ance X >##?
100
$00
300
%00
A00
a(io#e!er ea(ing R >5#$?
10%$
%%6
$$0
1$A
80
Table !5 &o4arithm
Log10 X
$&00
$&30
$&%8
$&60
$&70
Log10 R
3&00
$&6A
$&3%
$&10
1&90
E"eri#en! G Table 35 Readin4 for Source Temerature* Ambient Temerature* Radiometer and "ner4y "mitted by nit Area of a Blac= Body Surface
E.+*S Source Te#"era!ure
.#bien! Te#"era!ure >T A?
C.LCUL.TF+S
a(io#e!er ea(ing > R?
T S
T A
q b
=
[T
σ
%
S
−
T A% ]
ea(ing >T S ? o
o
C
5#$
-
-
5#$
30
$7
160
303
300
18&6A
0&117
39
$7
A7A
31$
300
78&01
0&136
77
$7
1999
3A0
300
391&A8
0&196
C
7
3.! 'rah
'rah 15 'rah of Radiometer Readin4 R a4aint Ditance #
8
'rah ! 5 &o4:lo4 $lot of Radiometer Readin4 a4aint Ditance
3.3 Calculation
Conersion of oC>celcius? !o ->-elin? -= oC H$73 =77H$73 =3A0 -
*ra(ien! of !he slo"e be!2een log10 an( log10 I #=
2.70 −2.00 1.9 −3.0
=0&6%
9
Calcula!ion of !her#al energy ra(ia!e( by a
q b
=
[T
σ
%
S
−
blacbo(y ra(ia!or "er secon( "er uni! area4
T A% ]
= A6&7 B 109 >31$% 300%? = 78&01 5#$
α
Calcula!ion for α
=
=
q b R 78.01 575
= 0&136
3.( Dicuion
y looing a! !he gra"h4 2e can see !ha! !he in!ensi!y of !he ra(ia!ion is inersely "ro"or!ional !o !he (is!ance be!2een !he hea! source an( !he ra(io#e!er in gra"h1& This has sho2n !ha! !he in!ensi!y of !he ra(io#e!er (e"en(s on !he (is!ance of !he ra(io#e!er an( !he hea! source& The fur!her !he ra(io#e!er is a2ay fro# !he hea! source4 !he lo2er !he in!ensi!y of !he ra(io#e!er& .s sho2n in gra"h $ as 2ell4 2e can see !ha! Log 10 R is
10
inersely "ro"or!ional !o Log10 X. .s calcula!e( in !he calcula!ion "ar!4 2e !hen foun( ou! !ha! !he gra(ien! is 0&6%&
.s 2e loo a! !able34 i! is sho2n !ha! 2hen !he "o2er is se! !o !he #ini#u#4 !he !e#"era!ure sho2n on !he !e#"era!ure rea(ing is 30 oC& The rea(ing on !he ra(io#e!er sho2s !ha! !he ra(io#e!er is 160 5#$ &The !e#"era!ure is 39 oC 2hen !he "o2er is se! !o !he #e(iu# leel& The ra(io#e!er !hen sho2 a rea(ing of A7A 5#$ & The ra(io#e!er sho2s a rea(ing of 1999 5#$ 2hile !he "o2er is se! !o !he #ai#u# leel 2hich has a !e#"era!ure of 77 o C& .#bien! !e#"era!ure is cons!an! !hroughou! !he 2hole e"eri#en! 2hich is $7 oC sa#e as !he roo# !e#"era!ure& y obsering !he "a!!ern of !he resul!s4 2e no2 !ha! 2hen !he "o2er increases 2hich #aes !he !e#"era!ure !o increase4 !he in!ensi!y of !he ra(io#e!er also increases& 5i!h !he hel" of S!efanol!:#ann La24 2e can calcula!e !he α is
α 2hich
is 0&1174 0&136 an( 0&196 res"ec!iely& Calcula!e( aerage for
0&1A& The (ifferen! alue of
α is
(ue !o so#e error occur in !he e"eri#en!& u! s!ill
2e can "roe !ha! !he S!efanol!:#ann La2 is cre(ible&
(.0 "rror Analyi
ro# !he gra"h aboe4 2e can see !ha! !he alues are a bi! (ifferen! fro# !he !heore!ical alue& This can be e"laine( as error occurs (uring !he "rocess of con(uc!ing
11
!he e"eri#en!& The error !ha! #ay occur in !his e"eri#en! #igh! be ran(o# an( sys!e#a!ic error& Fne of !he ran(o# error is cause( by hu#an errors&
5hen con(uc!ing !he
e"eri#en!4 by looing a! !he a""ara!us !o #easure !he (is!ance #ay cause so#e error as !he eyes is no! "arallel !o !he #easuring !a"e& This 2ill lea( !o !he inaccuracy of !he resul! for !he e"eri#en!& esi(es !ha!4 !he a""ara!us 2hich is rus!y #ay also cause error !o occur& 5hile !he sys!e#a!ic error is cause( by !he ga(ge!s 2e hae aroun( us 2hich #ay effec! !he rea(ing of !he ra(io#e!er because our ga(ge!s e#i!s ou! ra(ia!ion as 2ell& The o!her sys!e#a!ic error 2hich occurs is (ue !o !he a""ara!us 2hich can only go u" !o 1999 5#$ & This #eans !ha! !he rea(ing of !he ra(io#e!er #igh! go higher bu! (ue !o !he li#i! of !he rea(ing of !he ra(io#e!er& y haing all !hese errors occur4 2e can #ini#i:e i! by re"ea!ing !he e"eri#en! a fe2 !i#es !o ge! !he aerage resul! !o increase !he accuracy of !he e"eri#en!& esi(es !ha!4 !he uniersi!y shoul( be generous enough !o change !he a""ara!us or u"gra(e i! so !ha! 2e can ge! a #ore accura!e resul! 2hile con(uc!ing !he e"eri#en!&
).0 Concluion .f!er con(uc!ing !his e"eri#en!4 2e can see !ha! !he in!ensi!y of !he ra(io#e!er (e"en(s on !he (is!ance of !he ra(io#e!er an( !he hea! source& 5e !hen can conclu(e !ha!
1$
!he in!ensi!y of !he ra(ia!ion is inersely "ro"or!ional !o !he (is!ance be!2een !he hea! source an( !he ra(io#e!er& Log10 R is inersely "ro"or!ional !o Log10 X 2hich has a gra(ien! of 0&6%& The alue of α is al#os! !he sa#e regar(less of !he changing of !he !e#"era!ure& n conclusion4 2e can "roe !ha! S!efanol!:#ann La2 is !rue&
+.0 Reference 1& unno2n& >$01%?& Introduction to the principle of heat transfer. .ailableG h!!"G//222&efun(a&co#/for#ulae/hea!!ransfer/ho#e/oerie2&cf#& Las! accesse( 30!h Se" $01%& &' Unno2n& >$01%?& Stefan-Boltzmann Law. .ailableG h!!"G//hy"er"hysics&"hy as!r&gsu&e(u/hbase/!her#o/s!efan&h!#l& Las! accesse( 30!h S e" $01%&
13