波浪传播数值模型波向角计算

波浪传播变形数值模型的抛物型近似在近海工程大范围水域的波浪推算中应用十分广泛，本文就抛物型缓坡方程（PMSE）数值计算中波浪方向的计算作了分析。首先从椭圆型缓坡方程（MSE）推导了波向角的计算方法；然后介绍大范围水域波浪折射绕射传播变形缓坡方程的抛物型近似法以及波向角的计算；最后，利用抛物型缓坡方程和椭圆型缓坡方程法分别对Berkhoff实验室地形条件下波浪场进行计算，比较两种方法计算得到的波向线图。比较结果显示抛物型缓坡方程法计算波向角结果与椭圆型缓坡方程法计算结果是一致的，抛物型近似法计算波向角是可行的。

Numerical analysis of wave direction on the nonlinear parabolic mild slope equation

Parabolic equation method for water wave is widely used to simulate the wave propagation from offshore to inshore. The purpose of this paper is to analyze the wave deflection angle which is caused by wave propagation. First, the computational equation of the wave direction from the elliptic mild slope equation is deduced. Second, the parabolic approximation model for solving the wave transformation process is introduced, and is used to solve the wave direction. Lastly, the comparison of the results between the parabolic model and the elliptic mild slope equation is carried out. It is shown that the deflection angles of the computational result in the two models have a good agreement. It can be concluded that the parabolic approximation of the wave propagation can calculate the wave direction.