【作者】 戴愚志；

【导师】 宋竞正；

【作者基本信息】 哈尔滨工程大学 ， 船舶与海洋结构物设计制造， 2003， 博士

【摘要】 本文着重研究提高三维水弹性分析计算效率的方法，为三维水弹性分析方法在海洋工程中的广泛应用创造条件。首先提出了使用Arnoldi过程确定GMRES方法重启动数的方法，按照向后误差分析的方法给出了GMRES方法的终止准则，使用GMRES方法求解了大型离岸结构的水弹性响应和平均二阶力(矩)，通过对大型离岸结构的水弹性分析表明GMRES方法的计算效率高于常规方法，可在工程应用中发挥巨大的作用。 随后，将预修正快速傅里叶变换方法由刚体水动力分析扩展到水弹性分析中，提出了一种使预修正快速傅里叶变换方法具有较少计算时间与较低占用内存的网格奇点布置方法，使用预修正快速傅里叶变换方法进行了单个弹性浮体和多个弹性浮体的水弹性分析，由于预修正快速傅里叶变换方法具有较高的计算效率，使得造船工程师使用预修正快速傅里叶变换方法在微机上就可以进行以往只有在工作站和并行机上才能实现的大型离岸结构的水弹性分析，满足了工程应用的要求。 由于海洋工程结构物湿表面各点的波浪压力各不相同，在经水动力或水弹性分析后，如何将波浪压力添加到数量众多的有限元单元上以对海洋工程结构物进行结构强度分析一直是造船工程师关心的问题。本文提出了一种基于PCL语言的对海洋工程结构物进行频域有限元分析的波浪压力自动加载方法，将水线处面元和水线以下面元分开处理，水线以下面元所承受的压力直接用PCL语言添加到面元上，把水线处四边形面元转化为三角形面元，将作用在三角形面元的分布压力转化为节点力用PCL语言添加到节点上，这一方法的提出解决了多年以来困扰造船工程师的一个难题。更多还原

【Abstract】 This paper lays emphasis on the method which can improve the calculating efficiency of 3-D hydroelastic analysis, and provides a good environment for the wide application of this analysis in ocean engineering. Firstly, the method of determining the restarted number of GMRES by using Arnoldi process is put forward, the stop criterion of GMRES is given by the backward error analysis. The hydroelastic response and the second-order mean force (and moment) of large offshore structure are solved by GMRES. Numerical tests show that the computational efficiency of GMRES is higher than that of conventional method and this method can exert tremendous effect in engineering application.Secondly, the precorrected-FFT method is expanded to the hydroelastic analysis from the rigid body hydrodynamic analysis, and a grid singularity collocation method is presented which can make the precorrected-FFT method use less calculating time and occupy less memory. The hydroelastic analysis of single and multiple elastic floating bodies is carried out by the precorrected-FFT method. Due to the high computational efficiency of the precorrected-FFT method, the naval architects now can use this method on personal computers to solve the hydroelastic response of large offshore structures that could be computed only on workstations or parallel computers many years ago, which means that the precorrected-FFT method has met the demand of engineering application.Because of the difference of the hydrodynamic pressure on the wet surface of marine structures, it is the naval architects’ concern for a long time that after the hydrodynamic or hydroelastic analysis how to add the hydrodynamic pressureonto numerous finite elements so as to analyze the structure strength of marine architecture. In this paper we propose a method based on the Patran Command Language which can automatically load the hydrodynamic pressure for the FEM analysis of marine structures in frequency domain. The elements on waterline and below waterline are treated separately. The pressures acting on elements below waterline are added onto the panels directly using PCL. The quadrilateral elements on the waterline are translated into triangle elements. The distributed pressure on the triangle elements are translated into concentrated force and added onto the nodes using PCL. This method thoroughly solves the difficult problem that has puzzled the naval architects for many years.更多还原