Development of a free surface flow solver for the simulation of wave/body interactions

A two-fluid free surface flow model, that can simulate wave interactions with stationary or moving bodies, has been developed. The incompressible Navier-Stokes (NS) equations are solved using a finite difference solver with an efficient particle level set method to track the interface between water and air. A semi-Lagrangian approach and the fast marching method have been applied to solve the level set equation and, with the aid of the locally deployed particles, to reinitialize the level set function. To represent solid stationary and moving boundaries in the flow field effectively, a partial cell treatment combined with a local relative stationary method has been implemented. A new simple level set boundary condition for both fixed and moving bodies is proposed. The free surface flow model has been validated for a number of 2D and 3D benchmark test cases for applications to complex flow situations involving the violent motions of water, air and their interfaces, as well as their interaction with fixed or moving bodies. Detailed comparisons between the numerical results and available analytical solutions or experimental data show that the model is generic, accurate and holds promise for the numerical simulation of such flow problems.