A Study into the Use of Pseudo Random Binary Sequence Pressure Disturbances to Measure Sonic Velocity in a Two-Phase Flow System

Abstract

A literature survey into gas-solids flow has revealed that most of the existing work is of a theoretical nature. Of fundamental importance to this theoretical work is the concept of sonic velocity. Presented here is a novel method that enables this parameter to be measured experimentally. The technique used is to inject small amplitude pseudo random binary sequence pressure disturbances into a two-phase flow system and compute a cross-correlation function between two measuring locations within the flow system. The time shift of the peak value of this function gives a direct measure of the sonic velocity existing between these two locations. The experimental results demonstrate that by using a pseudo random pressure disturbance on-line evaluation of sonic velocity becomes feasible.