Unsteady cavitating flow based on the hybrid turbulent model

A hybrid turbulence model which contains both space and scale information is developed. Cavitating flow around a hydrofoil is simulated using a transport equation. To simulate turbulence effects on cavitating flows, three different models are implemented. The time evolutions of the shape of cloud cavities, the lift and drag force around the hydrofoil are obtained, and compared with experimental results. It is shown that three turbulence models can predict successively the characteristic of cavitation and the detailed process of the cavitation shedding. Compared with the FBM, a modified k -ε turbulence model, the hybrid turbulence model is found to more accurately predict the void ratio, velocity fields, and cavity length by adjusting the turbulent viscosity in the cavitating flow. Results obtained by the hybrid method are found in good agreement with the experimental ones.