Numerical simulation of unsteady 3D cavitating flows over axisymmetric cavitators

A three dimensional numerical study of unsteady turbulent cavitating flows around a circular disk and a cone cavitator. Cavitating flows which can occur in a variety of practical cases can be modeled with a wide range of methods. The RANS (Reynolds Average Navier Stokes) equations and an additional transport equation for liquid volume fraction are solved by using finite volume approach through the SIMPLE algorithm. In this simulation, a truncated Rayleigh-Plesset equation is applied for bubble dynamic. Also specific numerical modifications are used in a finite volume approach to promote robust solution when cavitation is present. Moreover, the VOF method is adopted to track the interface between the liquid and the vapor phases. For implementation of turbulent flow, the shear stress transport, k−ωk−ω model is selected. The main characteristics of the cavity are analyzed and compared with experimental data. The present results for both cases are in good agreement with experimental data and analytical relations. These agreements confirm the authority of this simulation to be implemented in more complicated shapes.