LES investigation of cavitating characteristics around a 3D Sphere

In this paper cavitation over a sphere at Reynolds number of 1.5×106 and broad range of cavitation numbers (0.36 < σ < 1) is reported. A large-eddy simulation of cavitating flow is compared to the non-cavitating flow at the same Reynolds number. Cavitation is observed to significantly influence the evolution of pressure, vorticity, velocity, streamlines, boundary layer and loads on the sphere surface. The wake characteristics are compared to the single-phase results at the same Reynolds number and it is observed that cavitation suppresses turbulence in the near wake region and delay the three-dimensional breakdown of the vortices. The governing equations and the turbulence model in originally completeforms are employed in the OpenFOAM; intephaseChangeFoam solver. The stable different range of cavity regimes and the periodic shedding of the cavitation bubble are predicted. The volume fractions contour of the cavity cloud which obtained from numerical simulation are compared to experimental results and good agreement is observed

کلیدواژه ها:

Unsteady cavitation ، Sphere ، Numerical simulation ، Vortex structure ، wakes