DASAR LAUT SINUSOIDAL SEBAGAI REFLEKTOR GELOMBANG

This article discusses about the influence of sinusoidal sandbars towards the amplitude of incident wave. sinusoidal sandbars may lead to Bragg resonance. Basically, when a wave meets a different depth, it will scatter into a transmitted wave and a reflected wave. Bragg resonance happens when the wavelength of incident wave is twice of the wavelength of the periodic bottom disturbance. We apply the multiscale asymptotic expansion to obtain the results. Eventually we find that a larger amplitude disturbance leads to larger reflected wave amplitude. This result explains that the sinusoidal sandbars indeed can reduce the amplitude of incident wave and protect a beach from large amplitude incident waves.