Waves in rectangular inlet with reflecting or absorbing walls

The behavior of water waves in the vicinity and within an inlet through an idealized barrier island is studied. Two mathematical approaches are used: the first treats the waves in the ocean and bay with Fourier transforms; and the second uses 'buffer' domains, which permit the far-field waves to be treated by eigen-function expansions. The first method is used to treat an inlet with reflective vertical sidewalls. In nature, inlets lined with armor stone absorb wave motion; therefore, the second method is used with impedance boundary conditions at the inlet sidewalls to reduce the wave energy propagating down the channel and into the bay. Wave patterns in the inlet can vary significantly with the angle of incident wave and so can the direction of the radiated wave field in the bay.