海浜変形数値モデル

Abstract

The numerical model for beach change predictions is developed in this paper.The model consists of three modules which are wave propagation, nearshore currentsand sediment transport.For engineering practices the wave propagation model is necessity to simulatethe wave field where effects of refraction, diffraction, reflection and energydissipation are simaltaneously considered. The mild slope equation transformed to asystem of hyperbolic partial differential equations enable its calcualtion with easyposing of various boundary conditions.A horizontally 2-D model is employed for the nearshore current simulation, inwhich the effects of sea-bottom topography changes are simaltaneously taken intoconsideration. ADI finite difference technique is used for its numerical calculation.Bailard's sediment transport model which considers both effects of local sea bottomslope and nonlinear asymmetry of water particle motion of waves is employed inthe equation of continuity of sea material transport.By some necessary model tests, the model efficiency is confirmed.