Hybrid RANS–LES Modeling for Unsteady Cavitating Flow Simulation

Abstract

A typical hybrid RANS-LES approach, DES (Detached Eddy Simulation), was introduced into cavitating flow simulation in this paper. The applicability of two DES models, including one equation DES model and SST k-ω DES model, and standard k-ε model was analyzed through experimental data of a water tunnel experiment. Validation results illustrate that the precision of DES method depends on the RANS model used and the length scale used to distinguish LES zone and RANS zone. The SST k-ω DES method can well predict cavitating flow. The averaged results gained through this model are better than those of standard k-ε or one equation DES model. By comparison, the one equation DES model shows little advantage than standard k-ε model to simulate cavitating flow.

Study on the Influence of Temperature on the Temporal and Spatial Distribution Characteristics of Natural Cavitating Flow around a Vehicle

“…Kunz et al [44] simulated an unsteady cavitating flow on a hydrofoil using the RANS and detached-eddy simulation (DES) methods, comparing the evolution of the cavity and the changes in lift and drag. The separation vortex approach combines the advantages of RANS and LES: the RANS method is used for simulating the near-wall area to reduce the grid size and calculation time, with the LES method used to simulate the area away from the wall to capture large-scale separated flows [45][46][47].…”