Turbulent Hydrofoil Cavitation Simulations: Applications of RANS with Eddy Viscosity and Interfacial Turbulence Damping and LES

The performance of various turbulence modelling methods for simulating cavitating flow over a hydrofoil was investigated. VOF mixture modelling was applied for the multiphase flow, along with a standard two-equation turbulence model, a hybrid RANS-LES method, and a wall-modeled LES approach. The simulations were conducted in a numerical cavitation tank with experimental data available for a range of Reynolds numbers and cavitation conditions. A Reboud damping for eddy viscosity was applied (hereafter referred to as SST-R). A less common approach, incorporating interfacial turbulence damping based on physical arguments regarding the wall-like behavior of phase interfaces, was also applied (referred to here as SST-D). Our results indicate that the standard RANS method fails to predict the breakdown of lift with decreasing cavitation numbers, a phenomenon observed in the experiments and in earlier studies. Incorporating turbulence damping at the cavity interface or directly on the eddy viscosity improves predictions for both URANS and hybrid RANS-LES methods. Both the SST-D and SST-R agreed well with available experimental data, and the LES method consistently provided accurate results across all numerical grids.