ZHANG Hong-wei, LIU Zhi-ping, ZHANG Dong, WU Yi-hong (China Institute of Water Resources and Hydropower, Beijing 100038, China)

Abstract: With a one-dimensional two-fluid model and employing the small perturbation analysis, the propagation of the pressure wave in the water-gas two-phase bubbly flow was investigated. The governing equations are simplified and closured according to high-speed aerated flow characteristics in hydraulic engineering. The effects of aerated concentration, liquid pressure, perturbation frequency and interfacial forces on the acoustic wave velocity and its attenuation in the aerated flow are explored in detail. The results show that the sound velocity of the aerated flow decreases significantly with aerated concentration; the decrease of pressure and enhancement of heat transfer can reduce sound velocity while accelerate attenuation of sound wave; the virtual mass force mainly affects high-frequency sound velocity and slows down the sound wave attenuation.

Key words: aerated flow, two-fluid model, sound velocity, attenuation

Published in: Journal of Hydraulic Engineering, Vol. 44, No. 9, 2013