Flow Measurement
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MEASURING FLOW Dr JD Millington, UWE October 2014 EXPERIMENTAL DATA Gap meter Gravimetric Venturi Enlargement Orifce Bend re!ing " #nit$ %g $ $ $ "" "" "" "" "" "" "" "" 4 & 12 1' 20 ! GRAVIMETRI" Gap meter Gravimetric re!ing #nit$ l($ $ l($ 4 & 12 1' 20 #! VENT$RI Gap meter Venturi re!ing #nit$ l($ "" "" 4 & 12 1' 20 %! &$DDEN ENLARGEMENT Gap meter &udden Enlargement re!ing Lo$$e$ #nit$ l($ "" "" "" "" "" 4 & 12 1' 20 '! ORI(I"E Gap meter Orifce re!ing #nit$ l($ "" "" 4 & 12 1' 20 )! BEND Gap meter Bend re!ing Lo$$e$ #nit$ l($ "" "" "" "" "" 4 & 12 1' 20 t 1 t 2 t ) * 1 * 2 * 1 * 2 * 1 * 2 * 1 * 2 St#!ent$ to !+#$t t*e o-rte $o t*t t*e g. "eter "e$#re$ 4, &, 12, 1' n! 20 #nit$, !eter"ing t*e gr/i"etric /ol#"e o- rte n! recor!ing t*e #.$tre" n! !o-n$tre" .re$$#re$ or t*e ent#ri, enlrge"ent, ori3ce n! ben! ec* ti"e 5 g. t /erge 5 67 5 g. ro" clibrtion c#r/e 5 67 8 9" ( ρ: ( t /erge " 8 "$$ 9%g:, ρ 8 !en$it; 9%g ( " ) :, t /erge 8 9t 1 < t 2 < t ) : ( ) 9$: St#!ent$ to .lot 5 67 9= =i$: gin$t 5 g. 9; =i$:> t*e gr!ient o t*i$ line 9interce.t t 0,0: $*o#l! be 1 0 i t*e g. "eter i$ clibrte! correctl; 5 g. * 1 * 2 5 ? 5 g. ro" clibrtion c#r/e l ( $ 5 ? 8 A 1 92 g 9* 1 * 2 : ( @9D 1 ( D 2 : 4 1 : 0 B A 1 8 π D 1 2 ( 4> D 1 8 0 02' "> D 2 8 0 01' ", St#!ent$ to .lot 5 ? 9= =i$: gin$t 5 g. 9; =i$:> t*e gr!ient o t*i$ line 9interce.t t 0,0: i$ t*e !i$c*rge coeCcient 9$$#"ing 5 g. 8 5 A : 5 g. * 1 * 2 1 2 ( 2 g 2 2 ( 2 g n 8 5 ( A n > A n 8 π D n 2 ( 4 D 1 8 0 02' ", D 2 8 0 0B1" Lo$$e$ 8 9* 1 < 1 2 (2g: 9* 2 < 2 2 (2g: St#!ent$ to !e"on$trte t*t lo$$e$ 9; =i$: re .ro.ortionl to 1 2 ( 2g 9= =i$: 5 g. * 1 * 2 5 ? 5 g. ro" clibrtion c#r/e l ( $ 5 ? 8 A 1 92 g 9* 1 * 2 : ( @9D 1 ( D 2 : 4 1 : 0 B A 1 8 π D 1 2 ( 4> D 1 8 0 0B1 "> D 2 8 0 020 ", St# ent$ to . ot 5 ? = =i$ gin$t 5 g. ; =i$ > t e gr ient o t i$ ine interce.t t 0,0 i$ t e i$c rge coecient $$#"ing 5 g. 8 5 A : 5 g. * 1 * 2 1 2 ( 2 g 2 2 ( 2 g n 8 5 ( A n > A n 8 π D n 2 ( 4 D 1 8 0 0B1 ", D 2 8 0 040" Lo$$e$ 8 9* 1 < 1 2 (2g: 9* 2 < 2 2 (2g: St#!ent$ to !e"on$trte t*t lo$$e$ 9; =i$: re .ro.ortionl to 2 2 ( 2g 9= =i$:
description
Flow Measurement - lab experiment
Transcript of Flow Measurement
Student blankEXPERIMENTAL DATAGap meterGravimetricVenturiEnlargementOrificeBendreadingmt1t2t3h1h2h1h2h1h2h1h2unitskgsssmmmmmmmmmmmmmmmm48121620Students to adjust the flowrate so that the gap meter measures 4, 8, 12, 16 and 20 units, determing the gravimetric volume flow-rate and recording the upstream and downstream pressures for the Venturi, enlargement, orifice and bend each time.
1. GRAVIMETRICGap meterGravimetricreadingQgaptaverageQHBQgap from calibration curveunitsl / ssl / s4QHB = (m / r) / taverage812m = mass (kg), r = density (kg / m3), taverage = (t1 + t2 + t3) / 3 (s)1620Students to plot QHB (x-axis) against Qgap (y-axis); the gradient of this line (intercept at 0,0) should be 1.0 if the gap meter is calibrated correctly
2. VENTURIGap meterVenturireadingQgaph1h2QTQgap from calibration curveunitsl / smmmml / s4QT = A1 (2 g (h1 - h2) / [(D1 / D2)4 - 1])0.5812A1 = p D12 / 4; D1 = 0.026 m; D2 = 0.016 m, 1620Students to plot QT (x-axis) against Qgap (y-axis); the gradient of this line (intercept at 0,0) is the discharge coefficient (assuming Qgap = QA)
3. SUDDEN ENLARGEMENTGap meterSudden EnlargementreadingQgaph1h2V12 / 2 gV22 / 2 gLossesVn = Q / An; An = p Dn2 / 4unitsl / smmmmmmmmmm4D1 = 0.026 m, D2 = 0.051m812Losses = (h1 + V12/2g)-(h2+V22/2g)1620Students to demonstrate that losses (y-axis) are proportional to V12 / 2g (x-axis)
4. ORIFICEGap meterOrificereadingQgaph1h2QTQgap from calibration curveunitsl / smmmml / s4QT = A1 (2 g (h1 - h2) / [(D1 / D2)4 - 1])0.5812A1 = p D12 / 4; D1 = 0.051 m; D2 = 0.020 m, 1620Students to plot QT (x-axis) against Qgap (y-axis); the gradient of this line (intercept at 0,0) is the discharge coefficient (assuming Qgap = QA)
5. BENDGap meterBendreadingQgaph1h2V12 / 2 gV22 / 2 gLossesVn = Q / An; An = p Dn2 / 4unitsl / smmmmmmmmmm4D1 = 0.051 m, D2 = 0.040m812Losses = (h1 + V12/2g)-(h2+V22/2g)1620Students to demonstrate that losses (y-axis) are proportional to V22 / 2g (x-axis)
MEASURING FLOW
Dr J D Millington, UWEOctober 2014
ResultsEXPERIMENTAL DATAGap meterGravimetricVenturiEnlargementOrificeBendreadingmt1t2t3h1h2h1h2h1h2h1h2unitskgsssmmmmmmmmmmmmmmmm4654.852.354.42952762942962922722752718633.332.732.430025629529829624525424412623.123.123.131422830330931020822620516617.917.717.733619131832733115618715220614.214.414.73691493363503639414288Students to adjust the flowrate so that the gap meter measures 4, 8, 12, 16 and 20 units, determing the gravimetric volume flow-rate and recording the upstream and downstream pressures for the Venturi, enlargement, orifice and bend each time.
1. GRAVIMETRICGap meterGravimetricreadingQgaptaverageQHBQgap from calibration curveQHBQgapunitsl / ssl / s0040.12153.80.111QHB = (m / r) / taverage0.1110.12180.19632.80.1830.1830.196120.26923.10.260m = mass (kg), r = density (kg / m3), taverage = (t1 + t2 + t3) / 3 (s)0.2600.269160.35417.80.3380.3380.354200.43514.40.4160.4160.435Students to plot QHB (x-axis) against Qgap (y-axis); the gradient of this line (intercept at 0,0) should be 1.0 if the gap meter is calibrated correctly
2. VENTURIGap meterVenturireadingQgaph1h2QTQgap from calibration curveQTQgapunitsl / smmmml / s0040.1212952760.133QT = A1 (2 g (h1 - h2) / [(D1 / D2)4 - 1])0.50.1330.12180.1963002560.2020.2020.196120.2693142280.282A1 = p D12 / 4; D1 = 0.026 m; D2 = 0.016 m, 0.2820.269160.3543361910.3660.3660.354200.4353691490.4510.4510.435Students to plot QT (x-axis) against Qgap (y-axis); the gradient of this line (intercept at 0,0) is the discharge coefficient (assuming Qgap = QA)
3. SUDDEN ENLARGEMENTGap meterSudden EnlargementreadingQgaph1h2V12 / 2 gV22 / 2 gLossesVn = Q / An; An = p Dn2 / 4V12 / 2 glossesunitsl / smmmmmmmmmm0040.1212942962.6470.1790.468D1 = 0.026 m, D2 = 0.051m2.6470.46880.1962952986.9460.4693.4776.9463.477120.26930330913.0840.8846.200Losses = (h1 + V12/2g)-(h2+V22/2g)13.0846.200160.35431832722.6591.53112.12822.65912.128200.43533635034.2142.31117.90334.21417.903Students to demonstrate that losses (y-axis) are proportional to V12 / 2g (x-axis)
4. ORIFICEGap meterOrificereadingQgaph1h2QTQgap from calibration curveQTQgapunitsl / smmmml / s0040.1212922720.199QT = A1 (2 g (h1 - h2) / [(D1 / D2)4 - 1])0.50.1990.12180.1962962450.3180.3180.196120.2693102080.450A1 = p D12 / 4; D1 = 0.051 m; D2 = 0.020 m, 0.4500.269160.3543311560.5890.5890.354200.435363940.7300.7300.435Students to plot QT (x-axis) against Qgap (y-axis); the gradient of this line (intercept at 0,0) is the discharge coefficient (assuming Qgap = QA)
5. BENDGap meterBendreadingQgaph1h2V12 / 2 gV22 / 2 gLossesVn = Q / An; An = p Dn2 / 4V22 / 2 glossesunitsl / smmmmmmmmmm0040.1212752710.1790.4733.706D1 = 0.051 m, D2 = 0.040m0.4733.70680.1962542440.4691.2409.2291.2409.229120.2692262050.8842.33619.548Losses = (h1 + V12/2g)-(h2+V22/2g)2.33619.548160.3541871521.5314.04532.4864.04532.486200.435142882.3116.10750.2046.10750.204Students to demonstrate that losses (y-axis) are proportional to V22 / 2g (x-axis)
MEASURING FLOW
Dr J D Millington, UWEOctober 2014
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