A GPU-accelerated domain decomposition method for numerical analysis of nonlinear waves-current-structure interactions

A fully nonlinear near-far fields coupling solver is proposed in this work. The target is to provide an efficient numerical tool for wave-current-structure interaction simulations. A GPU-accelerated high-order spectral (HOS) solver is developed to simulate the wave propagation and interaction with current in large far field and an incompressible flow solver with free surface capture scheme from the OpenFOAM library is adopted in the near field to solve the nonlinear wave loads and seakeeping response of the ship hull. The newly developed HOS solver is firstly validated by two wave-current interaction test cases, including a regular wave train travelling on collinear following and opposing current, and regular waves blocked by strong opposing current. Then, the near and far field coupling solver is applied to a simulation of the seakeeping response of a cruising ship hull in head wave condition. Lastly, The proposed method is applied to a more practical application, i.e. the self-propulsion of a hull in short crested spreading irregular waves. The numerical results are compared to the lab measurement data or numerical results, good agreements have been obtained. A fully nonlinear near-far field coupling method for marine-offshore applications is proposed in this work. The key features include:•The large far field is solved by the efficient high-order spectral (HOS) method.•The HOS code is further optimized by exploiting the GPU.•The wave-current interaction module is able to handle the wave-current-structure interaction simulations.•The near field domain is free to move within the far field domain, in order to support the ship towing or cruising simulations.•Finally yet importantly, the near and far field solvers are coupled in either runtime or file-based mode to suit different simulation needs. Four validation cases are presented:•Regular Waves on Collinear Current;•Regular Waves Blocking on Opposing Current•Seakeeping of Ship Hull in Head Waves•Ship hull self-propulsion in 3D spreading irregular waves The validation results suggest that the present method is superior to its precedent.