A HYBRID 3D VORTEX METHOD FOR FLOW OVER SHIP PROPELLER

摘要

Flow over a ship propeller was computed at a Reynolds number of 5.6 x 10~5, using the hybrid vortex method in which vortex particle methods in main flow was combined with Prandtl-like approximation in numerical boundary layer. The positions of vortex blobs in main flow are updated by convection. Approximation of the vorticity in the boundary layer consists of smoothed 2D circular sheets parallel to the boundary. The fast vortex method was also adapted for reducing the computing time. As the result of the present study, the hybrid 3D vortex method is found to be acceptable for high Reynolds number flow calculation, since the computed time-averaged propulsion agreed well with the measured one.