Towards guidelines for consistent wave propagation in CFD simulations

Accurate prediction of structures and vessels motion at sea is critical to guarantee the safety and comfort of passengers on board, but also to understand the underlying physics of the derived quantities such as added resistance in waves. In this paper, a grid topology based on linear wave theory is proposed to efficiently and accurately propagate waves in a CFD domain. The grid topology consists of 3 refinement zones used to capture respectively the air-water interface, 90% and 99.9% of the wave kinetic energy. The performed sensitivity study showed that the error on wave dispersion, dissipation and reflection can all be contained within 2% using reasonable number of cells per wave length and amplitude. An application to the prediction of the motions of a 2D hull section in beam-on seas shows that using the guidelines derived lead to a good agreement with the results of a potential flow code, under the condition that the wave reflections are under control.