CFD Simulations of PMM Test using Local Grid Refinement with an Overset Grid Method

To study the influence of the vortical flow around a ship on the hydrodynamic forces and maneuvering performance, PMM test are simulated by CFD with local grid refinement method. It is confirmed that the local grid refinement method is effective for computing the detail of vortical flow and also the refined grid gives slightly better hydrodynamic forces than the original grid. All hydrodynamic derivatives and hydrodynamic interaction factors are calculated from the present CFD results and simulations of zigzag test and turning circle test are performed by the MMG model with the obtained derivatives and interaction factors. The simulation results show reasonable agreement with the experimental data. In order to improve the accuracy of maneuvering simulations, it is considered that discrepancies of some hydrodynamic derivatives and hydrodynamic interaction factors between CFD and experiments must be reduced. Further investigations on the local grid refinement method will enable the practical applications of simulation based maneuvering performance evaluations.