Numerical simulation of propeller tip vortex cavitation based on helical mesh encryption

Aimed to simulate the vortex cavitation at the tip of the propeller blade, the computational fluid dynamics (CFD) Star-CCM+ software was applied in the numerical simulation of marine E779A propeller. LES method and Schnerr-Sauer cavitation model were employed for cavitation simulation. To generate a more precise grid, helical tube was adopted for volume control on the position where tip vortex cavitation may occur in the propeller. In this way, the tip vortex cavitation of E779A propeller was simulated in a more refined numerical simulation. The comparison between the numerical and experimental results shows that the present method has satisfying numerical prediction accuracy. The thrust, torque coefficient and open water efficiency by numerical simulation agree very well with those by experiments. A numerical simulation of tip vortex cavitation based on helical mesh was carried out. It can be seen from the simulation results that the flow in the spiral region is more precisely simulated, and the velocity and pressure distribution of the dense tip vortex are clearly displayed. The comparison of numerical and experimental cavitation shows that the cavitation of propeller can be predicted very well by the proposed method, especially the shape of tip vortex cavitation. © 2020, Editorial Board of Journal of Huazhong University of Science and Technology. All right reserved.