Abstract
A new finite-difference method which can cope with strong interface motions is developed. The air and water flows are simultaneously solved in the time-marching solution procedure for the Navier-Stokes equation. The marker-density technique and the porosity techinique are devised for the implementation of the interface and the body-boundary conditions, respectively. Two test computations are performed, one is a 2D breaking flow of regular periodic wave generated by a numerical wave maker, the other is a 3D breaking flow about a ship-like body. The accuracy is examined and improvement of the method is described by the comparison with the records of physical experiments.
