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Calibration of Laminar Flow Meters for Process Gases



John D. Wright, Thiago Cobu, Robert F. Berg, Michael R. Moldover


We calibrated three models of commercially-manufactured, laminar flow meters (LFMs) at four pressures (100 kPa, 200 kPa, 300 kPa, and 400 kPa) with five gases (N2, Ar, He, CO2, and SF6) over a 10:1 flow range using NIST’s primary flow standards as references. We combined three items: (1) the calibration data acquired with N2, (2) gas-property data from NIST’s database REFPROP 9.0, and (3) a physical model for each LFM that accounts for the effects of viscosity, entrance and exit effects, gas expansion, gas non-ideality, and slip. This combination predicted the calibrations for the flow of Ar, He, CO2, and SF6 with a maximum error of 0.8% for Reynolds numbers Re
Flow Measurement and Instrumentation


laminar flow meter, calibration, gas species, gas properties, rate of rise, dynamic flow standard, gravimetric flow standard, process gases


Wright, J. , Cobu, T. , Berg, R. and Moldover, M. (2012), Calibration of Laminar Flow Meters for Process Gases, Flow Measurement and Instrumentation, [online], (Accessed April 15, 2024)
Created June 1, 2012, Updated February 19, 2017