Numerical study of the reentrant jet and twin vortex flow regimes in the ventilated cavitation

Abstract

Ventilated cavitation is generated artificially by injection of air through very precise openings in the profile. The main parameters of a ventilated cavitation are the gas supply injected rate and the gas leakage rate at rear of the cavity. The unsteady ventilated cavitation is characterized by gas regimes, of which there is three types [3]: portion gas-leakage, twin vortex gas-leakage, gas-leakage from pulsating surpercavities. The experimental observations show, in the twin vortex gas-leakage case, for low ventilation air flow coefficient it is the reentrant jet regime which appears. The present numerical study concerns the twin vortex gas leakage regime around the conical head bodies. The study is based on the 2D numerical code IZ models unsteady cavitating flows. In the present work, dissolved non-condensable gas is taken into account in the transport equation-based model in this numerical code. The numerical results are compared and validated with experimental measures [1] and an analysis of the transition between the reentrant jet and twin vortex is presented. © Published under licence by IOP Publishing Ltd.