Effect of currents on nonlinear waves in shallow water

Effect of various forms currents on regular nonlinear waves in shallow water is investigated by use a computational fluid dynamics approach. A range wave conditions with different heights and periods are considered. three types these investigated, namely (i) uniform current over the depth, (ii) shear from seafloor to still-water level, (iii) custom profile that changes depth. The profiles considered both following opposing directions incoming wave, forming total 18 wave–current configurations. Navier–Stokes equations for laminar flow solved computationally two dimensions. numerical maker created generate combined water. effect change field, including quantitative surface elevation, height, wavelength, horizontal particle velocity, velocity pressure fields presented discussed. It found presence can alter field significantly, direction play significant role field. increases peak pressure, along an increase wavelength while reduces these. height appears be opposite observed deep literature. also concluded linear superposition undisturbed velocities describe (particularly under trough) reasonably well, but larger differences currents.