!"#" $%&' "ngineering !easurements (ab Spring $') *epartment o !echanical engineering +ate leason #ollege o "ngineering Rochester Rochester institute o technology % *ubai
Lab 5- Experiment 5, Pipe friction loss in smooth bore pipe Abstract
In this lab, we shall examine the head loss due to viscous fow o the fuid through smooth bore pipe. Some o the governing components that will be considered are Friction actor, Reynolds number and fow rate. The relationship between head loss, riction and velocity o the fow will be determined.
Introduction
$
In this experiment , we tried to determine the relationship between head loss
due to fuid riction and velocity or fow o water through smooth bore pipes and to con-rm the head loss, riction actor / the experimentally obtained values o the coe0cient o riction using e1. 23 will then be compared with established results by plotting them on the !oody chart 2-gure 3 provided. The bends and turns in the pipe will cause the velocity o the fowing fuid to change which in turn a4ects the pressure hence giving rise to more head loss. There are two types o fow that can exist in a pipe. These are5 • •
(aminar fow at low velocities 2where h 6 73 Turbulent fow at high velocities 2where h 6 7 n3
8here h is the head loss due to riction and u is the velocity -eld. The transition phase between laminar and turbulent fow has no de-nite relationship between h and 7. f
=
∆ h 2 gd lv
2
( 1)
Figure 1 Moody Diagram
9
The objectives of the experiment: To -nd the relationship between head loss due to fuid riction Find velocity o fow o water through smooth bore pipes Find the value o riction coe0cient
Experimental Procedure: •
:rime the pipe networ; with water.
•
calculation3, :ipe length = >.? cm Ta;e readings at several di4erent fow rates, altering the fow using the
•
control valve on the apparatus. !easure fow rates using the volumetric tan;. For small fow rates use the measuring cylinder. !easure head loss between the tapings using the portable pressure meter or pressuri@ed water manometer as appropriate.
Formulas used in calculating: Experimental Data: Table 1 tabulated data Volume (ml)
AA' A'
Volu me (m)
'.''' AA '.''' A
Tim ! e actua (s) l (m"s ) B. '.''' & $ B.9 '.''' ) >
Veloc it# (m"s)
.B& .$A
$e#no lds %umb er
h& (m m)
h' (m m)
h (m)
>A'B. 9? )9?9. '
&$A
B)A
'.?
?&&
B?'
'. &
easur ed Friction Factor
Friction Factor (ood# *hart)
$."%'$
'.'$9
$."%'$
'.'$?
B
)' ?'' 9B'
'.''' ) '.''' ? '.''' 9B
B.B 9 9.A 9 9.B
'.''' & '.''' 9 '.''' '
.' '.>' '.&>
?''B. &? $$$$. '' >9&$.' &
?$? B&A B$'
B9' B'' 9&?
'.'> ? '.'& A '.'? ?
$.9"%'$
'.'$)
$.?"%'$ 9.B"%'$
'.'$> '.'9?
Apparatus used for the experiment
For this experiment, we used TQ H408 Fluid friction apparatus and TQ H408 piezometer.
Figure 2. TQ H408 Fluid frictio apparatu!.
Figure 3. TQ H408 piezometer
Results and graphs:
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velocit# v s head loss '.& '.B '.$
2x3 = '.$x % '.'B RC = '.>)
'. head loss m
'.'A '.'& '.'B '.'$ ' '.&'
'.)'
'.A'
'.>'
.''
.'
.$'
.9'
.B'
.?'
velocity 2mDs3
Figure 4 "elocity "# $ead lo!!e!
Errors and precautions: "rrors in the calculated riction actor and the riction actor value obtained rom moody chart is calculated using e1 2$35 EEEEE = EEEEEEEE EEEEEE2EEEEE3 EEEEEEEE EEEEEE 2EEEEEEEEEE3 2$3
errors +,++'-&.. +,++/'''+/ +,++/-/+'01 +,++///.'+ +,++&&2/&&
Figure % Table of error!
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These errors occur due to many several actors li;e5 • • •
Guman error in measuring Gead (oss. Inaccurate measurement o the length o the pipe. "rror in measuring the volume o water in the raduated
•
cylinder. Hir bubbles in the pie@ometer tubes.
Discussion: 7sing the *arcy and 8eisbach "1uation we calculated the rictional actor values provided with the h values. Reynolds number is also calculated and using these values, the values o calculated / is compared to the values in moody chart. we see that there are some di4erences between the riction actor obtained rom the moody chart and the riction actor obtained rom the rictional head loss e1uation 23, values in table . This di4erence can be attributed to experimental errors, including measuring the length o the pipe and measuring h 2Gead (oss3 during the experiment.
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