Effect of pitch ratio on the cavitation of controllable pitch propeller

This paper numerically investigated the effects of the pitch ratio on the cavitation of a controllable pitch propeller. The geometric model of marine propellers is obtained by changing the pitch of the propeller VP1304. The computational fluid dynamics (CFD) solver STAR-CCM+ and large eddy simulation (LES) turbulent model are used to analyze marine propellers. The open water characteristics and cavitation behavior obtained by numerical simulation are in good agreement with available experimental data. Because the controllable pitch propeller always operates under high-efficiency conditions, the open water characteristic curves of four propellers with different pitch ratios are first calculated to obtain the corresponding advance coefficients at the highest efficiency point. Then the cavitation behavior at the highest efficiency points of four propellers with different pitch ratios is analyzed. As the pitch increases, the main type of cavitation gradually changes from leading edge cavitation to hub vortex cavitation. In addition, the causes of different cavitation types are analyzed from the aspects of pressure and velocity distribution.