【作者】 李国安；

【导师】 叶恒奎；

【作者基本信息】 华中科技大学 ， 船舶与海洋结构物设计制造， 2007， 博士

【摘要】 满足线性自由面边界条件和物面边界条件的时域格林函数法用於分析多体排水型船的兴波阻力和波形计算。计算的时域点源的兴波波形与计算的Havelock源的兴波波形进行对比,得到了满意的结果。在物体湿表面进行时域源分布的网格法用於单体船,双体船和三体船的兴波计算,得到了合理的结果,本文给出了多体船在给定付氏数下的自由面的兴波仿真。近水面水翼的兴波由升力线的自由面兴波来表达,船体的兴波考虑升力线兴波的干扰影响,三维时域格林函数法用于船体的兴波分析计算。以Wigley船型为数值计算例,考虑近水面水翼的影响,分别对单体船和双体船进行了船舶兴波计算研究,提供了兴波波形和兴波阻力的计算结果。以系列60船型为数值计算例,把计算的结果与发表的有关结果进行对比。本文还对水翼船舶自由表面兴波波形进行了时域数值仿真。在波浪与浮体相互干扰的水动力时域分析计算中,本文提出了一种时域格林函数网格法的数值模型,对半球的垂荡运动进行了有关计算,把计算结果与有关结果进行了对比,有良好的一致性。发展的时域Rankine源网格法用于半球的纵荡和垂荡运动计算,计算的力的时间记忆函数与相关的文献资料进行了对比,证明了本方法的有效性。用开发的时域势流有限元方法对Wigley 3012船型的纵向运动(纵荡,垂荡和纵摇)的辐射力进行了分析计算,并且与时域格林函数网格法的计算结果进行了对比,结果满意。利用理想流体的欧拉方程,用有限元方法建立了波体干扰计算模型。在自由表面上应用了线性自由面边界条件,非定常的欧拉方程用分步法求解。时间步进积分法分别用于处理压力泊松方程,速度方程和自由面上的波浪运动。为了证明本文提出的计算方法,在自由面上摇荡的半球用于作为数值计算例,把计算结果与用不同的理论方法得到的结果进行了比较。更多还原

【Abstract】 A method of threedimensionaltime domain Green function satisfying linearconditions at free surface and body surface boundary was employed to analyze the waveresistance and wave profile of a displacement multihullship. The wave profile inducedby a moving time domain point source was compared with those by a Havelock source,and satisfactory results were obtained. The panel method based on the time domain sourcedistribution on the ship mean wetted hull surface was used to perform the wave makingcomputations for monohullships, catamaran and trimaran. Reasonable results were alsoobtained. Using the numerical method the wave profile simulations of multihullships fora given Froude number were conducted.The wave making of the hydrofoil is represented by the lifting line. The ship wavemaking incorporated with the hydrofoil is computed by 3DGreen function method intime domain. Wigley hull form with hydrofoil is employed as numerical example for thecomputation of monohullship and catamaran. Some computed results are presented. TheSeries 60 hull form is also used as numerical example and the computed results arecompared with published data. The ship wave making on the free surface is simulated intime domain.In the time domain analysis for the interaction of wave and floating body, anumerical scheme with time domain Green function panel method is developed and somerelative computations are carried out for a floating hemisphere. Good agreements havebeen obtained by comparing with others. Rankine source panel method is used for thememory function computation of hemisphere in surge and heave, respectively and theefficiency of the computational method is verified. The finite element method isdeveloped to compute the time domain radiation force of Wigley (3012) hull form in surge, heave and pitch motions. The computed results have been compared with those by timedomain Green function method and the satisfied agreements are also obtained.A wavebodyinteraction computation scheme, based on Euler’s equation in the idealfluid, is formulated by the finite element method (FEM). The linear free surface boundarycondition is used. The unsteady Euler’s equation is solved by the fraction step method andthe time step marching integration approach is employed to deal with the pressure Poissonequation, velocity equations and the wave motion on the free surface, independently. Toverify the present method a floating hemisphere oscillating on the free surface isintroduced for a numerical computation example. The computed results have beencompared with those by different theoretical methods.更多还原