FLOW THROUGH VENTURI METER

FLOW THROUGH VENTURI METERAim of the Experiment:-To calibrate venturimeter with different β* ratios. Determine the flow head relationship for thisflow meter.Determine the effect of Reynolds number on the coefficient of discharge (C D ).*β is the ratio of throat diameter to pipe diameterApparatus required: CCl 4 manometer, Hg manometerProcedure:Data:-1. Keep the bypass valve completely open and the main valve completely closed. Switch onthe pump.2. Connect a CCl 4 manometer across the venturi.3. Open the main valve and set a flow rate of water using the rotameter.4. Note down the rotameter reading and manometer reading after a steady state is attained.5. Increase the flow rate by opening the main valve and throttling the bypass valve suitablyand repeat step 4.6. Use mercury manometer for higher flow rates.7. Take readings with CCl 4 manometer as well as with Hg manometer.8. Repeat the experiment with different β ratios and with different fluids.Diameter of the pipe = d =cmDiameter of the venture throat= d t =cmDensity of CCl 4 = CCl= Kg/m 34Density of Hg =Hg= Kg/m 3Density of fluid = ρ = Kg/m 3Viscosity of fluid= μ =cp

Observations :-Sl.No. Rotameter reading LPM Manometer Reading∆Hm cmCalculations:-Flow rate:∆Hm = cm of manometric fluid.Volumetric flow rate = Q = m 3 /sHw mx Hm= density of manometric fluid.m= m of H 2 OAverage velocity through the throat =Qvt m / sAtA t = Cross sectional area of throat= 2d4 t

β = d t /d =Reynolds Number at the throat=Coefficient of discharge = Cd =QA d t tN vRet=412gt H wSl.No.Qm 3 /s∆H mcm ofManometricfluidv om/s∆H wm H 2 oN Re/tC dpower ofPlot Q vs H CCl and Q vs H4Hg on an ordinary graph (Calibration).Plot C d vs N Ret on a semilog graph sheet (with N Ret on log scale )Plot log Q vs log Hw Hw .Find the slope and the intercept. Find the coefficient and. Comment on the nonlinear flow head relationship. Obtain Cd from the plot.Results:Report on calibrationComment on C d vs N Ret

Report the CdComment on flow head relationship.Compare C d for orifice and venturimeter.