Numerical investigation of the effect of the rectangle-type cavitating-bubble generator on the sheet/cloud cavitating flow around the NACA66 hydrofoil

Abstract

The objective of this work is to present the effect mechanism of a passive control method using a spanwise rectangle-type cavitating-bubble generator (CG) on the unsteady partial cavitation based on the simulation. First of all, the numerical method using a Partially-averaged Navier–Stokes (PANS) turbulence model was validated and showed the good agreement with the experiment. Then the effects of CG on different cavitation stages were studied separately. It is found that the CG has a significant effect on the unsteady process of sheet cavity, and it can effectively mitigate or suppress the cavity shedding behavior, especially for the incipient cavitation stage with larger cavitation numbers. Correspondingly, the time-fluctuation amplitude of the wall-pressure, lift and drag for the hydrofoil with CG are reduced dramatically. In addition, the time-averaged lift-to-drag ratio of hydrofoil is improved desirably after using the CG. The conclusion of this work will be promising for the cavity dynamic controlling field.