A viscous flow solver for time-dependent free surface calculations

In the present work, a robust and efficient algorithm for the computation of steady and time-dependent viscous fluid flow about advancing ships is developed. The baseline numerical algorithm couples the method of artificial compressibility with a finite volume cell-center discretization of the Reynolds-averaged Navier-Stokes equations. An efficient multigrid time-stepping scheme with residual smoothing and local time-stepping is implemented, resulting in an algorithm with fast convergence rates. Dual time-stepping is used to advance the system of equations in a time accurate manner. Fully nonlinear treatment of the wave field is provided by conforming the grid to the free surface shape. This core scheme is implemented for solution on parallel computers using the method of domain decomposition. The resulting computational tool is highly efficient and provides fast and accurate solutions of fluid flow about general hull shapes. Demonstration of the method for computation of the hydrodynamic forces on a Wigley hull in regular headwaves is presented.