The CFD technique for the viscous flow field around a ship has been developed and enabled us to stably acquire the solution with high accuracy. However, in the case of taking wave-making resistance into consideration, there still exists many problems. As for the CFD technique, the importance of the time discretization tends to be undervalued, while there are lots of discussions concerning how spatial discretization, i.e. grids system, influences the computational results. In this paper, a numerical investigation concerning the time increment for the computation of the viscous flow with waves around a ship has been conducted. Some examples of application of newly developed method to several ship configurations like VLCC and high-speed ship are to be shown.
