Flow Measurement & Applications This quiz focuses on one of the most practical areas of Fluid Mechanics — Flow Measurement and Applications. It covers essential instruments like Venturi meters, Orifice meters, Pitot tubes, and Notches, helping you understand how fluid flow is measured in real-world systems. 1 / 20 The flow rate through a Venturi meter is proportional to Reciprocal of pressure difference √(Pressure difference) Pressure difference Square of pressure difference According to Bernoulli’s equation, discharge varies as the square root of the pressure difference. 2 / 20 Coefficient of discharge accounts for Energy losses and contraction Only energy losses Only contraction None of these It includes both energy losses and contraction effects, correcting theoretical flow rate. 3 / 20 The discharge through a V-notch varies as √h h^2 h^(3/2) h^(5/2) For a V-notch, discharge is proportional to h^(5/2), providing higher sensitivity for small flows. 4 / 20 A weir is used for measuring discharge in Pipes Nozzles Open channels Closed conduits Weirs are barriers across open channels that allow flow measurement by head variation. 5 / 20 The discharge through a notch or weir varies as Head Square root of head Square of head Cube of head Flow rate is proportional to √h because it follows Bernoulli’s principle. 6 / 20 A Venturi meter gives more accurate results than an orifice meter because Flow separation is more Velocity is less Turbulence is high Energy losses are less Smooth flow and gradual contraction in a Venturi meter minimize energy losses. 7 / 20 In a flow-measuring device, if the differential head increases, discharge Increases Decreases Remains constant First increases then decreases Higher pressure difference means greater velocity and thus greater discharge. 8 / 20 The coefficient of velocity for an orifice is generally 0.98 0.65 0.70 0.85 Coefficient of velocity indicates actual to theoretical velocity ratio, usually about 0.98. 9 / 20 A rectangular notch is used when Velocity is low Flow is laminar Discharge is large Discharge is small Rectangular notches are best for measuring large discharges accurately. 10 / 20 The discharge coefficient of an orifice meter depends on Pipe diameter Pipe length Pipe material Reynolds number Discharge coefficient changes slightly with Reynolds number due to viscous effects. 11 / 20 The flow rate through a nozzle is maximum when the exit pressure equals Critical pressure Atmospheric pressure Zero pressure Gauge pressure Flow becomes choked at critical pressure, giving maximum discharge 12 / 20 The Pitot-static tube measures Velocity of flow Pressure difference Head loss Discharge It measures the dynamic pressure to calculate velocity using Bernoulli’s principle 13 / 20 The head loss in an Orifice meter is Equal to Venturi meter Negligible Less than Venturi meter More than Venturi meter Orifice meters cause greater head loss due to sharp-edged plates and flow separation 14 / 20 A V-notch is generally used for measuring Compressible flow Small discharges Large discharges High-pressure flow V-notches provide accurate measurement for small discharges because of their sensitivity. 15 / 20 The device used for measuring discharge in open channels is Notch Venturi meter Pitot tube Orifice Notches (like rectangular or V-notch) are used to measure flow rates in open channels. 16 / 20 The coefficient of discharge for a Venturi meter is approximately 0.55 0.65 0.75 0.98 The Venturi meter has a high coefficient of discharge (~0.98) due to low energy loss. 17 / 20 Which instrument measures flow velocity directly? Orifice meter Venturi meter Manometer Pitot tube A Pitot tube measures the stagnation and static pressure difference to directly find the flow velocity. 18 / 20 The discharge through an Orifice meter is measured by observing Velocity of flow Pressure difference across the orifice Area of pipe Head loss The flow rate in an Orifice meter is calculated using the pressure drop across the orifice plate. 19 / 20 In a Venturi meter, the pressure is lowest at the Inlet Outlet Throat Any section Velocity is maximum at the throat, so pressure is minimum due to energy conservation. 20 / 20 The Venturi meter works on which principle? Bernoulli’s principle Continuity equation Pascal’s law Newton’s law The Venturi meter measures flow using pressure difference between the throat and inlet, based on Bernoulli’s theorem Your score isThe average score is 0% 0% Restart quiz
