A comparison of two different types of shoreline boundary conditions

Two different types of shoreline boundary conditions which can be used in either wave-resolving or wave-averaging models of waves and currents propagation in the nearshore are compared here. The two techniques are essentially different: in the first case the velocity of the shoreline is obtained by the momentum equation and the shoreline position is tracked by changing the grid position, while in the other case the velocity of the shoreline is obtained by a modified Riemann solver and the shoreline is defined as an interface between dry and wet fixed grid points. A number of test cases are described to compare the performance of the two techniques.

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