A transport equationbased cavitation model was developed according to the homogeneous assumption in this paper.The mechanism of evaporation and condensation was considered in the model.The noncondensable gas was also taken into account in cavity formation and development.The RNG turbulence model was employed with a modified turbulent viscosity according to the mixed density.The proposed model was implemented to simulate the steady cavitating flow around a NACA66 airfoil.The pressure coefficient distributions on the suction side of the foil agreed well with the experiment results.Furthermore,the effects of noncondensable gas,inlet turbulent kinetic energy and turbulence dissipation rate on the cavity length were evaluated.The proper values of noncondensable gas,inlet turbulent kinetic energy and turbulence dissipation were selected.Then,the proposed model was applied to an unsteady cavitating flow.The numerical results clearly reflected the whole process of the cavitationcloud generation,growth,dispersion and collapse.The simulation showed re-entrant jet is one of the main reasons for the breakoff process.The Strouhal number obtained agreed well with the experiment results.The overall results prove the reliability of the proposed model in cavitating flow simulations.
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