Fluid Flowmeters - Comparing Types

A comprehensive comparison of different fluid flowmeter types including differential pressure, velocity, positive displacement, mass, and open channel flowmeters with their characteristics, principles, and selection considerations.

Flowmeter TypeCategoryTurn Down RatioAccuracyPressure RecoveryCostCommon Applications
Orifice PlateDifferential Pressure< 5:1Poor at low flowLowVery LowGeneral applications
Venturi TubeDifferential Pressure10:1GoodUp to 80%MediumHigher turn down applications
Flow NozzleDifferential Pressure< 5:1Similar to OrificeMediumLowAir and gas flow
Variable Area (Rotameter)Differential PressureUp to 12:1Up to 1% FSN/ALowLaboratory and process control
Pitot TubeVelocityVariableGoodN/AVery LowVentilation, HVAC, Aircraft
Calorimetric FlowmeterVelocityVariableHigh at low flowN/AMediumLow flow measurement
Turbine FlowmeterVelocity> 100:1Better than ±0.1%N/AMediumHigh accuracy applications
Vortex FlowmeterVelocityVariableGoodN/AMediumIndustrial applications
Electromagnetic FlowmeterVelocityVariableGoodN/AHighConductive liquids, corrosive fluids
Ultrasonic DopplerVelocityVariableGoodN/AHighNon-contact measurement
Positive DisplacementPositive DisplacementUp to 70:1Up to 0.1% FSN/AMediumOils, viscous fluids
Thermal Mass FlowmeterMass FlowVariableVariableN/AMediumIndependent of density/pressure
Coriolis FlowmeterMass Flow> 100:1Better than ±0.1%N/AHighUniversal liquids, slurries, gases
Weir/FlumeOpen ChannelVariableGoodN/ALowOpen channels, rivers, water plants