Investigation of cavitation around 3D hemispherical head-form body and conical cavitators using different turbulence and cavitation models

Abstract

In this paper, cavitation and supercavitation around 3D hemispherical head-form body and a conical cavitator were simulated. Dynamic and unsteady behaviors of cavitation were solved using large eddy simulation (LES) and k-ω SST turbulence models, as well as Kunz and Sauer mass transfer models. In addition, the compressive volume of fluid (VOF) method is used to track the cavity interface. Simulation is performed under the framework of the OpenFOAM package. The main contribution of this work is to present a correlation between the cavity length and diameter for hemispherical head-form bodies for the first time. Moreover, we provide a detailed comparison between different turbulence and mass transfer models over a broad range of cavitation numbers, especially in small cavitation numbers, including σ=0.07, 0.05, 0.02 for two cases, which is not reported previously. Our numerical results are compared with the available experimental data and a broad set of analytic relations for the cavity characteristics such as cavity length and diameter with suitable accuracy. Discussions on boundary layer separation and re-entrant jet behavior, which play a significant role in the bubble shedding in the cavity closure region, are presented.