Flow Coefficient Characteristics of Quadrant Edge Orifice

Abstract

Described in this paper is a limit of useful range of a quadrant edge orifice to be used for fluid measuring device for low Reynolds number. From the results both of author's laboratory test on 16mm pipe and of Bogema's test on 2-inch pipe, it was proved that the lower limit of the range of constant flow coefficient of a quadrant edge orifice is 3000-4000 and not 300-400 (Reynolds number) which is shown in Koennecke's data and has been widely used.