A EULERIAN-LAGRANGIAN METHOD FOR THE SIMULATION OF WAVE-PROPAGATION

A Eulerian-Lagrangian method (ELM) is employed for the simulation of w ave propagation in the present research. The wave action conservation equation, instead of the wave energy balance equation, is used. The wa ve action is conservative and the action flux remains constant along t he wave rays. The ELM correctly accounts for this physical characteris tic of wave propagation and integrates the wave action spectrum along the wave rays. Thus, the total derivative for wave action spectrum may be introduced into the numerical scheme and the complicated partial d ifferential wave action balance equation is simplified into an ordinar y differential equation. A number of test cases on wave propagation ar e carried out and show that the present method is stable, accurate and efficient. The results are compared with analytical solutions and/or other computed results. It is shown that the ELM is superior to the fi rst-order upwind method in accuracy, stability and efficiency and may better reflect the complicated dynamics due to the complicated bathyme try features in shallow water areas. (C) 1998 Elsevier Science Ltd. Al l rights reserved.