Statistical Improvement in Differential Producer Type Flowmeters

Abstract

First steps have been taken to demonstrate the feasibility of reducing uncertainties in the use of differential producers. Given a suitable flow conditioner, discharge coefficients are shown to be a highly reproducible function of approach length L/D. In the case of venturis and throat-tap flow nozzles, large effects of excessively small pressure tap diameter ratio δ/d are demonstrated and correlated, and much of the scatter and the premature roll-off of the coefficient with decreasing Reynolds number are thus accounted for. Some influence of throat length ratio x/d upstream of a throat tap is shown.