Solitary wave slamming on an Oscillating Wave Surge Converter over varying topography in the presence of collinear currents

A fully nonlinear model based on a higher-order boundary element method is established to investigate the slamming on an oscillating wave surge converter in the nearshore environment. In this proposed model, the extreme wave is generated using internal sources with solitary wave theory and travels with collinear currents over an uneven bottom. The time-domain solution including current velocity and wave perturbation potential is acquired and updated through the mixed Euler-Lagrangian method. Both the truncation method and the domain decomposition method together with the non-breaking criterion ensure that the numerical procedure will not end up with a singular matrix caused by an irregular splash jet until the wanted results have been attained. The auxiliary functions are defined to decouple the flap motion and waves in the existence of currents. It has been found that the opposing currents enlarge and delay the solitary wave slamming on the flap. When there is a convex obstacle at the flume bottom, a distinct diffusion of two solitons has been observed due to the twin variations in water depth, and thus, the flap is subjected to two slamming pressure peaks with different magnitudes in one procedure of rotating seawards.