深水时域格林函数的实用数值计算

A practical numerical method for deep water time-domain Green function

如何精确而又快速地计算时域格林函数及其导数是求解船舶水动力问题的关键。论文基于Bessel函数的性质推导了深水格林函数及其导数所满足的常微分方程,提出了结合求解常微分方程的节点制表、节点间插值的快速计算格林函数的方法。数值计算表明该计算方法克服前人节点制表节点间插值计算方法的缺点,提高了格林函数的计算效率和数值精度。

How to calculate time-domain Green function and its gradients efficiently is the key problem to analyze ship hydrodynamics in time domain. Basing on the Bessel function, an Ordinary Differential Equation （ODE） was derived for time-domain Green function and its gradients and is presented in this paper. A new efficient calculation method by taking the advantage of solving ODE is proposed, which can improve the precision of the time-domain Green function, and it is proved by the numerical calculation.