Eulerian two-phase modeling of cavitation for high-speed UUV using different turbulence models

The cavitation will occur when the speed of UUV(Unmanned Underwater Vehicle) exceeds the threshold. The research of cavitation is significant for the high-speed UUV research. Two different turbulence models are respectively used to study the time-averaged and instantaneous cavitation two-phase flows in the present work. The Euler-Euler approach is used to describe the phase equations of the water and vapor. The Schnerr and Sauer model is used to describe the mass transfer due to the cavitation. Firstly, the time-averaged cavitation flow in a cylindrical model is simulated using the renormalization-group(RNG) k-ε turbulence model. Good quantitative agreement with experimental data is obtained both for the vapor volume fraction and static pressure of different cavitation numbers. Next, transient computation is performed using the large eddy simulation(LES) with Smagorinsky subgrid scale model(SGS) to study the time-dependent cavitation flow of a hydrofoil model. The predicted transient cavitation behavior and cavities shedding in the hydrofoil model agree well with experimental observations. Thus, the LES can be effectively used for studying the cavity shedding and the instantaneous cavitation flow.