近岸波浪及沿岸流数值模拟研究

Numerical simulation of wave field and coastwise current in alongshore zone

利用抛物型缓坡方程计算波浪场,并以波浪辐射应力为近岸动力因素,建立深度平均的二维近岸流的控制方程。运用该近岸流方程,对美国Santa Barbara Leadbetter海岸波浪斜向入射所产生的波浪场及波浪破碎所形成的沿岸流进了数值模拟,其中抛物型缓坡模型采用Crank-Nicolson格式进行数值离散,近岸流方程采用ADI差分格式离散。与现场实测资料的对比表明,无论考虑或不考虑波浪非线性因子,模拟结果与实测结果均吻合良好。

The wave field is calculated by the parabolic mild slope equation and the wave radiation stress is regarded as the major factor to establish the mathematical model for simulating the coastwise current due to wave action based on the depth - averaged shallow water equation. The model is applied to numerically analyze the wave field and the coastwise current formed by the breaking of oblique incident wave in the Leadbetter Beach, Santa Barbara, California, USA. In the analysis the Crank-Nicolson scheme is adopted to solve the parabo the model of wave induced lic mild slope equation and the ADI finite difference scheme is applied to solve coastwise current. The simulation results are in good agreement with the field data.