Asymmetric behaviour of wind, wave and current interaction and its implications for coastal hazard and marine renewable energy

Better understanding of wind, wave and current interaction is of theoretical and practical significance for a wide variety of problems in the coastal zone and deep ocean. A two phase flow Navier-Stokes solver is combined with a Volume of Fluid (VOF) surface capturing scheme to investigate (1) wave breaking and blocking by spatially varying opposing currents, (2) wind and current effects on extreme wave formation and breaking, and (3) effects of vertical current shear on nonlinear wave interactions.  In this talk, we will take a close look at the asymmetric behaviour of wind, wave and current interaction and the influence of  opposing wind and current, which is not well understood.  The effects of wind, wave and current interaction on coastal hazard, sediment transport and marine renewable energy  will be illustrated through  case studies of coastal flooding and erosion  and marine renewable energy in Southwest England and Northeast USA, using structured and unstructured two-way coupled wave and ocean circulation models, ROMS-SWAN and ADCIRC-UNSWAN, and a sediment transport model.