🌊 Harbour Entrance: Wave Diffraction Through a Breakwater Gap, Shallow-Water Solver (2D)

Top view of sea waves running into a harbour through a gap in a breakwater, solved live on a grid with the linear shallow-water equations. Set wave height, period, depth, gap width and bottom friction, and watch the waves bend into the sheltered water and fade behind the wall. Wave speed, wavelength, the ratio of gap to wavelength, probes and a far-field pattern are shown, with four in-page numerical checks. A coastal-engineering companion to the 3D harbour wave twin.