三维二阶水波绕射问题的有限元时域计算

本文用有限元法配合时步处理来求解三维非线性水波的绕射问题，自由表面条件和物面条件都满足到二阶，采用人工阻尼区来吸收反射波，流场内的速度势通过求解有限元方程得到。对垂直圆柱体的绕射问题进行了计算，得到了自由表面波高时间历程和圆柱所受到的波浪力，计算结果和有关文献的理论计算结果进行了比较。

Calculation of time domain of second order wave diffraction in three dimensions with finite element method

The FEM with time marching is employed to analyze the time domain of second order non linear 3D water waves. The free surface boundary condition and the body boundary condition are satisfactory to second order at each time step. The diffraction wave is absorbed with an artificial damping zone instead of Sommerfeld radiation condition, and at each time step the velocity potential in the fluid field is solved by the FEM. The diffraction of the vertical circular cylinder is selected as a numerical example for verifying the efficiency of the present method. The time histories of wave elevations and wave forces on the cylinder are calculated. The results have been compared with those by the previous theoretical method.