Theoretical study of elastic effect of a cylindrical pipe wall on ultrasonic flow measurement

This paper addresses wave dynamics confined by an elastic fluid-filled pipeline with a uniform moving flow. The measurement deviation of an ultrasonic flow meter has been comprehensively analyzed with the flow profile ranging 0 m/s to 10 m/s. Governing equations of wave propagation are deduced based on isentropic process assumption in elastic solid and viscous fluid. Numerical analysis shows that acoustic modes in the elastic pipeline are different from those in a rigid-wall and a rod pipe. The wall thickness has obvious influence on the number of acoustic modes and phase velocity. Measurement deviations of elastic-wall pipeline are greatly different from those of rigid-wall pipeline. The wall thickness, wall material and acoustic frequency greatly affect the measurement deviation of each acoustic mode, showing that acoustic mode should be carefully selected in the implementation of an ultrasonic flow meter. Experimental validations are conducted to show the reasonability of theoretical analysis.