Effect of Measurement Volume on Ultrasonic Velocity Profile Method for Turbulent Flow Measurement. 1st Report. Discussion on Ensemble Averaged Velocity, Reynolds Stress and Flow Rate.

Abstract

This paper presents a velocity profile measurement using Ultrasonic Velocity Profile (UVP) measuring method. This method has many advantages over the conventional flow measurement methods. First, it has the capability to measurement of an instantaneous velocity profile on a line. Secondly, it is applicable to opaque liquids. This method can be applied to various flow measurements, but it requires a large measurement volume. In this paper, the ensemble averaged velocity profile and the Reynolds stress have been measured for fully developed turbulent pipe flows in a vertical pipe and the effect of the measurement volume on the measured values was estimated analytically. The results show that the effect of measurement volume appears in buffer region and viscous sublayer.