3D free-surface flow computation using a RANSE/Fourier-Kochin coupling

A coupling method for numerical calculations of steady free-surface flows around a body is presented. The fluid domain in the neighbourhood of the hull is divided into two overlapping zones. Viscous effects are taken in account near the hull using Reynolds-averaged Navier-Stokes equations (RANSE), whereas potential flow provides the flow away from the hull. In the internal domain, RANSE are solved by a fully coupled velocity, pressure and free-surface elevation method. In the external domain, potential-flow theory with linearized free-surface condition is used to provide boundary conditions to the RANSE solver. The Fourier-Kochin method based on the Fourier-Kochin formulation, which defines the velocity field in a potentialflow region in terms of the velocity distribution at a boundary surface, is used for that purpose. Moreover, the free-surface Green function satisfying this linearized free-surface condition is used. Calculations have been successfully performed for steady ship-waves past a serie 60 and then have demonstrated abilities of the present coupling algorithm.