Numerical experiments on transverse oscillations induced by normal-incident waves in a rectangular harbor of constant slope

In a rectangular harbor with a constant bottom slope, transverse oscillation may occur. This kind of wave has a maximum amplitude at the dead end of the harbor and decays exponentially in the offshore direction. This numerical investigation, using the nonlinear wave transformation model FUNWAVE 2.0, demonstrates the generation of subharmonic and synchronous transverse oscillations within a harbor induced by waves impacting normally on. The subharmonic transverse oscillations are trivial if the bottom slope is small, while the synchronous transverse oscillations are trivial and irrelevant for the bottom slopes. For checking the system responses, transverse oscillations within the harbor that also has a small bottom slope across the harbor were also examined. The generation of subharmonic oscillation seems not to be affected by a small transverse bottom slope; however, the synchronous transverse oscillations are enhanced significantly.

► We model the generation of transverse oscillations in a harbor of constant slope.
► The subharmonic transverse oscillations are trivial if the bottom slope is small.
► The synchronous transverse oscillations are trivial for all bottom slopes.
► A small cross-harbor bottom slope affects the synchronous resonance seriously.