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TABLE OF CONTENTS

CONTENTS Pages

ABSTRACT 2

1 INTRODUCTION 3

2 LITERATURE REVIEW 4

3.0 EXPERIMENT OBJECTIVE 5

4.0 METODOLO!" 6

#.0 RESULT AND DISCUSSION 9

1 Result 9

2 Discussion 11

$.0 CONCLUSION 13

% REFERENCES 14

ABSTRACT

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In a great measurement and analysis of liquid flow system by using the ariable !rea "#131$%

&rifice ' D( "#)31'#*31$ and )lectromagnetic flow meters "#*32$ was in+estigated, *he flow

rate reading at the #131% #)31'#*31 and #*31 local indicator is com-ared, arious flow rates

are -erformed as the mani-ulated +ariables, *he flow rate reading at #I31 were obser+ed at the

flow meter% for #)31'#*31 was recorded on .hannel 2 and .hannel 3 and the flow rate for

#*31 local indicator were calculated by using the formula #+ / 0h, *he e-eriment -resented

here show that almost the flow rate readings at #)31'#*31 were less than recorded by #*31local indicator and #I31, *he reason is that the loss of data during analogue data transmission

through the wire to the dis-lay, *he de+iation +alues also must be considered between both

readings, #or eam-le% instead of -ressure dro- in the -i-eline% there are some contaminated

de-osited on the -i-e wall that lead to bloc0age in the +al+e, ome recommendations here is that

the flow meter should be calibrated to increase the sensiti+ity and can reduce the errors during

handling the e-eriment, esides% we should lea+e the meter ust for a few seconds after

adusting is to stabilise the reading of the -rocess, ince we use +arious ty-es of flowmeters% the

+alues obtained were different% but all the +alues still acce-table because the de+iation is under

17 -ercent,

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1.0 INTRODUCTION

#low measuring de+ice generally fall into one of the two categories% namely% -rimary de+ices or

quantity meters and secondary de+ices 0nown as rate meters, *he distinction between the two is

based on the character of the sensing element that interacts with the fluid flow, *he out-ut of thesensing element is then suitable modified so as to indicate or record the measured +alues, It is

quite often -ossible to obtain the rate of flow from a quantity meter by a suitable choice of

modifying elements, #urther% it is im-ortant to note that the quantity meters are generally used

for the calibration of rate meters,

#low measurement are essential in many a--lications such as trans-ortation of solids as slurries%

com-ressed natural gas in -i-elines% water and gas su--ly systems to domestic consumers%

irrigation systems and a number of industrial -rocess control systems, *he selection of -articular flow measuring equi-ment de-ends -rimarily on the nature of the metered liquid and the

demands of the associated -lant, .onser+ation of energy states that all energy entering a system

at -oint 1 is also in the system at -oint 2% e+en though one form of energy may be echanged for

another,

P&'()'*+es

The Fluid Friction Law states that energy is required to o+ercome friction to mo+e fluid from

-oint 1 to -oint 2, #or the -ur-ose of calculating flows% certain assum-tions are made about the

stability of the system energy under steady flow, *he main energy concerns are the -otential and

0inematic energies, *he generali8ed statement of this energy balances is gi+en below

:)1 ; ()1 / :)2 ; ()2

:inetic energy ":)$ is energy of motion "+elocity$, (otential energy "()$ is energy of -osition

"-ressure$,

!dditionally% the other factor that go+ern the choice of a -articular flow metering de+ice are the

+arious -erformances -arameters li0e range% accuracy% re-eatability% linearity% dynamic res-onse%

ty-e of out-ut li0e analog'digital% etc, further% another requirement may be to indicate or record

the rate of flow% total flow or both these quantities,

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2.0 LITERATURE REVIEW

#low measurement is essential in many industries such as the oil% -ower% chemical% food% water%

and waste treatment industries, *hese industries require the determination of the quantity of afluid% either gas% liquid% or steam% that -asses through a chec0 -oint% either a closed conduit or an

o-en channel% in their daily -rocessing or o-erating, *he quantity to be determined may be

+olume flow rate% mass flow rate% flow +elocity% or other quantities related to the -re+ious

three".hatto-adhyay% 2776$.

*he instrument to conduct flow measurement is called flow meter, *he de+elo-ment of a flow

meter in+ol+es a wide +ariety of disci-lines including the flow sensors% the sensor and fluid

interactions through the use of com-utation techniques% the transducers and their associated

signal -rocessing units% and the assessment of the o+erall system under ideal% disturbed% harsh% or

-otentially e-losi+e conditions in both the laboratory and the field".hatto-adhyay% 2776$,

#or the case of steady uniform flow% a linear stability analysis on a general class of one<

dimensional models is for two<-hase flow, *he model equations contained only first<order

deri+ati+es and algebraic e-ressions% and accounted for the +irtual<mass force% the drag force%

-hase interaction and differences in -hase -ressures, It was assumed that both -hases were

incom-ressible, *he analysis showed that stability -ro-erties had no de-endence on -erturbation

wa+elength% and therefore hy-erbolicity was a necessary stability condition "=ones and

(ros-eretti% 19>5$,

! -hysical instability lies on the -rediction of the flow regime transition from stratified wa+y

flow to mied slug flow "*ra--, 19>6$,

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3.0 EXPERIMENT OBJECTIVE

*o study the +olumetric #low ?easurement using the ariable !rea "#I31$% &rifice ' D(

"#)31'#*31$ and )lectromagnetic flow meters "#*32$

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4.0 METODOLO!"

1$ ection @S,a&,-* C/e) L's, a( P&e+''(a& Ee&)'se5 was referred and -rocedures

from 1 to 17 were followed,

2$ arious flow meters was located and +olumetric flow rates was read as follows

FI31 ariable area flow meter Directly read at the flow meter FI31 678/9 near the

-um- discharge,

FE31 8 FT31 #or the &rifice<Differential (ressure LFR31% !&ee( Pe( "A$ "D($ flowmeter and C/a((e+ 2 "mB'h$ is then read,

FT32 #or electromagnetic flow meter C#R31% B+e Pe( "A$ C/a((e+ 3"mB'h$ was

read,

Res+, '( TABLE 1A was noted 6see RESULT SECTION9, *hen the flow rate indicator

C&.!CCE was read at the :+;< e,e& FT32 and com-ares it with C/a((e+ 3 a, ,/e

Re);&e& LFR31, *hey should be similar,

3$ *hen #)31'#*31 was used to +erify the O&':')e8DP :+;< e,e& *&'()'*+e ,/a, ,/e :+;<

&a,e 's *&;*;&,';(a+ ,; ,/e s=a&e &;;, ;: ,/e *&ess&e &;* '.e,

olumetric #lowrate%

F> ? @/%

where/ is the -ressure dro- across the &rifice -late #)31 measured by #*31

• (um- (31 was then o-ened for manual discharged +al+e fully,• #lowrate and -ressure dro- reading was ta0en as follows

a$ #lowrate "#+$ in mB'h at the Recorder .hannel 2,

b$ &rifice -late "#)31$ -ressure dro-% h% in 2O at the D( transmitter #*31,

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*his -ressure dro- reading "h$ has not been -rocessed or filtered yet by the D(

transmitterF hence it is noisy "fluctuating$, *hen% nominal mean or a+erage +alue for h

was ta0en,

• IV a, ,/e RESULT se),';( was referred for a sim-le calculation to +erify thatF

F> ? @/.

#low rate was then reduced by gradually shutting the -um- (31 manual discharge +al+e

"locate before the strainer$ to reduce the flow rate "&ea FT32$, Res+,s '( TABLE 1A

was noted,

4$ P&;)e&e 4 was re-eated at two "2$ other flow rates at a--roimately 1.0 78/ 633.39

and 0. 78/ 62$.%19 of the full scale flow rate of 3 mB'h,

*hen% loo0 u- the P&;)e&e 2 3 a( 4, *he reading was recorded in *!C) 1!

similarly,

• (rocedures was re-eated with increasing flow rates and the reading in *!C) 1!

was recorded,

6$ )-eriment then com-leted, *he -lant was SUT DOWN

• (um- (31% (32 at the front -anel'.ubicle is switched off,

• Recorder "C#R31$ chart dri+e is then switched off by -ressing its R.D -ushbutton

with its swing co+er o-ened,

• C;(,&;++e& LIC31 's s<',)/e ,; Ma(a+ 6M9 ;e with its out-ut ? / 7A,

elector witch is should be at -osition 1CI.31,

• *he -um- manual was fully o-ened by<-ass +al+e 32,

• ?ain -ower su--ly switch at the front of the cubicle was switched off,

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• *he manual +al+e for instrument air su--ly "I!$ was fully shut, !ir regulator was no

need to regulate,

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#.0 RESULT AND DISCUSSION

5,1 Result

Rea

din

g

no.

Fl

ow

rat

e

m³

/h

VOLUMECTRIC FLOW RATE READINGCalculate

the %

Deviation

fro !T"#

At

FI31

At the Recorder LFR31

!anel

At F"31 local

indicator

FI"#

FE"#$FT"# FT"

#ree

n $en

%han

nel 2

&l'e

$en

%han

nel 3

(Fv &

'()h

%om

!are

with

%ha

nnel

2

*AM

E

OR

NOT

m³/h ) m³/h ) m³/hmm(

2*m³/h

For

FI31

For

F"32

1 1.

21.3

38.33

1.14

34

1.2+ 13,,

1.12

-*"14.

+4 5.262 1.

+1.+

32+.,6

281.+2 1+67

+.,8-*"

4.1

6 6.253 +.

8+.85

26.67

+.8+2+.6

7

+.84 726.5

+.8+

A

0

6.2

5 54 +.

6+.65

1,.33+.58

13.6

7+.62

42+.+

3 +.61-*"

12.

1 6.,+5 +.

4+.5

12.66

+.382+.6

7

+.413,2.6

+ +.5,

-*"31.

56 7.8,

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6 +.

6+.65

1,.67

+.5,

27

+.623,4.+

+ +.6+

-*"1+.

2+ 5.+87 +.

8+.85

25+.75

33.3

3+.81

66,.+

4 +.78-*"

13.

33 88 1.

+1.+

31.33

+.,438.3

3

1.++1+55.

3 +.,7

-*"6.3

8 6.38, 1.

21.15

37.67

1.13

34

1.151471.

8 1.15

-*"1.7

7 1.77 "ale 1A Re'lt or the e!eriment

.alculation

#or )am-le on #low rate of 1,2 mB'h

A green -en A blue -en #+

/ channel 2 177

3

/ 1,15 177

3

/ 3>,33A

/ channel 3 177

3

/ 1,19 177

3

/ 434A

3

7,73

7,73 1399,7

1,12 '

Fv h

Fv

Fv m hr

=

=

=

#I31 A De+iation #*32 A De+iation31 31

A 177A31

1,37 1,14A 177A

1,14

A 14,74

FI FT

FT

−= ×

−= ×

=

32 31A 177A

31

1,27 1,14A 177A

1,14

A 5,26

FT FT

FT

−= ×

−= ×

=

1+

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5,2 Discussion

ased on the result that we achie+ed% it shows that there is a different on +olumetric flow

rate reading between .hannel 2 FE318FT31 andat FT31 +;)a+ '(')a,;& at some certain

measurement, Ge found out that the factors that may cause to affect this situation is as stated

below,

#irst% the flow meters being used are different between each other, .hannel 2 #)31'#*31

is an electromagnetic flow meter whereas #*31 local indicator is an &rifice Differential (ressure

flow meter, *his meter run when as the fluid a--roaches the orifice the -ressure increases

slightly and then dro-s suddenly as the orifice is -assed, *he decrease in -ressure as the fluid

-asses through the orifice is a result of the increased +elocity of the flow -assing through the

reduced area of the orifice, !s the +elocity decreases %the fluid lea+es the orifice and the -ressure

increases thus tends to return to its original le+el, *he -ressure loss is not reco+ered due to the

friction and turbulence losses in the stream, *he -ressure dro- across the orifice increases when

the rate of flow increases, Ghen there is no flow there is no differential, *he differential -ressure

is -ro-ortional to the square of the +elocity% it therefore follows that if all other factors remain

constant% then the differential is -ro-ortional to the square of the rate of flow, )lectromagnetic

flowmeter is a 0ind of inductional instrument designed by #aradayHs law of eletromagnetic

induction to measure inner<tube conducti+e mediaHs flow of +olume, *he measurements a--ear at

#*31 local indicator are more signifying because of its +iscosity effect is high% -ressure losses is

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medium and large range ability which is between 4 to 1, ut then% it still not too far from

electromagnetic reading,

econdly%the different of area ratio of -i-ing also affect the reading of the flowrate,

*heoretically% the +alue of #I31/#)31'#*31/#*32 should be a--roimately the same if the le+el

is 0e-t constant and any different recorded will show de+iation as indicated by A de+iation of

data #I31 and #*32 by e-erimentally, &therwise there will be differential in -ercentage of loses

cause by -i-e resistance regarding to lea0age or @by -ass or might be the instrument is

inaccurate and required further calibration chec0, *he #I31 is measured by +ariable area flowmeter while #*32 by electromagnetic flow meter, *he result shows of large difference between

#I31 and #*32 reading for A de+iation at the same flow rates, *his will be e-lained by energy

loses for long distance -assing through of #I31 and its si8ing -i-e which is smaller and higher in

+olumetric flow rates than #*32, e+eral ste-s should be considered in order to minimi8e the

de+iation, #irstly% we had to ma0e sure that the -i-ing always in clean and good condition

es-ecially -i-ing that oin to orifice flow meter so that resistance can be reduced, !nother thing

is the suc0ing and discharge -i-e need to be designed in suitable si8ing and long to the le+el of

tan0er,

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$.0 CONCLUSION

y referring to the result obtained from the e-eriment% we conclude that the stability is

going u- and the res-ond of fluctuation at *an0 31 reduced, *he obecti+es of the e-eriments

which with the aim of to study the +olumetric flow using +ariable area% orifice and

electromagnetic flow meters is achie+ed, *he -ercentage of the le+el transmitter is e-ressed by

the each of the maimum allowable liquid le+els, *he standard flow meter that used in this

e-eriment is not industry scaleF it is ust a lab scale system, o it is limited to ust monitoringthe higher flow rate +alue, It is referred as a+eraging le+el control by allowing the liquid le+el to

rise or fall in res-onse to inlet flow disturbances,

!s the conclusion%the increasing of stability and the res-ond of fluctuation at *an0 31 is

reduced, *he obecti+e of the e-eriment% to study the +olumetric flow using +ariable area%

orifice and electromagnetic flow meters is accom-lished, )ach of the maimum allowable liquid

le+els is e-ressed as a -ercentage of the le+el transmitter,

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%.0 REFERENCES

1$ R, G ?iller, #low measurement Jandboo0% "the ?cKraw<Jill .o,% LE% 19>3% 9<6$2 htt-''boo0s,google,com,my'boo0sM

id/7a7.h=oyayI.-g/((Ndq/CIOPID;#C&G;?)!PR)?)L*;!LD;!L!CE

I;<;.hatto-adhyay%;2776hl/ensa/Qei/q<

KD*mq)E(ErOf*?8Gg+ed/7.)oO6!)w!!S+/one-ageqf/true, retrie+ed

on 9 ?arch 2712

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