Experimental and numerical studies on inception cavitation around axisymmetric blunt body

Inception cavitating flow around axisymmetric blunt body was studied based on the experiments and numerical simulations. A high-speed video camera was used to observe the process and structure of cavitation inception. A Partially-Averaged Navier-Stokes (PANS) method which was a hybrid RANS/LES turbulent model was applied in numerical simulations. The results show that the inception cavities which are spindle-like generate in the separate vortex of the blunt body. Beside moving along with changing vortexes in the field, inception cavities rotate themselves around their longer axes of spindle-like cavities. Inception cavities move downstream far less slowly than the inflow does. It is shown in both experimental and numerical methods that during the whole developing process of travelling incept cavities, they move downstream by the velocities which are about 10% to 40% of mainstream velocity in this study.