有限水深复合格林函数的数值计算

Numerical calculation of finite water-depth composite Green function

有限水深格林函数值的正确求解对处于浅水的海洋结构物运动响应和载荷计算起着非常关键的作用。本文根据海洋结构物的物面对称性,在有限水深复合格林函数表达式的基础上推导出了格林函数偏导数的数值计算表达式,并对格林函数的奇异性进行了分析。采用抛物线积分法对其进行了积分,为有限水深海洋结构物的水弹性分析奠定了基础。计算结果表明,利用抛物线积分法所求得的运动响应与挪威DNV船级社SESAM软件的计算结果吻合得很好。

It plays a very important role in motion responses and hull loads calculation of ocean structures in shallow water to calculate correctly the numerical value of finite water-depth Green function. The numerical expressions of the derivative of finite water-depth composite Green function were deducted based on the symmetrical surface of ocean structures, and the singularities were analyzed. The integration of the numerical expressions of the derivative was carried out by parabola integration method in order to realize the hydroelastic calculation of ocean structures. It shows that the results of the motion responses obtained by the present method corresponds well with those of DNV SESAM.