孤立波对水下山包的绕射及开路边界条件的应用比较

在无界域的数值方法中,开路边界条件(Open Boundary Condition(OBC))是一个十分重要的研究课题.对于波动问题已有许多不同形式的OBC。但对它们的有效性,许多还缺乏在直接应用中的分析比较。本文以非线性长波的Boussinesq方程为控制方程组,在方形人为边界上采用了几类较重要的OBC,计算了无界水域中孤立波对水下山包的绕射。文中既给出了令人感兴趣的三维散射图案,又对这些OBC的有效性作了分析比较,对它们的可用性提出了一些有参考价值的意见。

THE DIFFRACTION OF THE SOLITARY WAVE BY A HUMP AT THE SEA BOTTOM AND PRACTICAL COMPARISONS OF THE DIFFERENT OBC

Open boundary condition (OBC) is one of the most challenge subjects in the field of computational method for infinite domain. There are already many different kinds of OBCs in wave problems. But, they still lack practical comparisons of effectiveness. This article devotes to such comparisons of several important OBCs at the artificial boundaries for the nonlinear wave equation Boussinesq equation. A test example is given on the diffraction of solitary wave by a hump at the sea bottom. 3-D scattering wave diagrams are also given. The effectiveness is analyzed with instructive conclusion.