中文摘要：

能在时域内准确求解三维波物相互作用问题的水动力对不规则波问题中的时域数值模拟具有很大的吸引力，为了研究应用时域理论对三维波物相互作用问题，采用基于Rankine源的边界元法计算每一时刻的流场，在自由面上采用积分格式的自由面条件（Integral-Formof Free-surface Boundary Condition，IFBC）；在：远方控制面上采用多次透射边界条件（Multi-Transmitting Formula，MTF）．文中讨论了基本参数对浮体受力的影响，同时对截断圆柱和半潜式平台的水波绕射问题进行了时域模拟，并将数值结果与频域结果进行了比较．结果表明，采用文中方法得到的数值结果准确、稳定和高效．

英文摘要：

A time-domain method is presented to simulate three-dimensional wave-body interaction problem that is deeply attracted by irregular wave domain in time domain. Based on Rankine source method, a Boundary Ele- ment Method （BEM） is used to calculate wave field at each time step. WJith an artificial wave speed a Multi- Transmitting Formula method （MTF） is employed to satisfy radiation condition to minimize the wave reflection. Furthermore, in order to update velocity potential on the free surface a stable Integration-form of Free-surface Boundary Condition （IFBC） is used. The present method is applied to simulate wave diffraction of truncated sur- face-piercing circular cylinder and semi-submersible platform, and the results compared with frequency solu- tions. It is shown that the method in this study is accurate, efficient and stz, ble.