正交异性超大浮体的水动力学分析
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摘要
关于超大浮体(VLFS)的研究开始于上个世纪八十年代。1991年，在美国的夏威夷召开了第一次关于VLFS的国际性会议。在那次会议之后，陆续有关于VLFS的文章发表。目前，VLFS的研究工作在ITTC和ISSC中占据了很重要的地位。全世界每年有超过100篇的论文发表。在我们国家，吴有生院士是第一个将这个概念引入学术领域的人。此外，他还推荐王大云和杜双兴两位博士与国外的研究人员共同合作，使用三维水弹性理论研究VLFS。
超大浮体的用途主要表现在三个方面：作为科研基地，开发海洋资源；作为解决陆地资源匮乏的手段之一。
研究VLFS的方法主要有两种，即直接法和模态分析法。大多数研究中使用的模态分析法，在使用这种方法时频率的计算是很重要的。最近的几年，直接法也逐渐被采用。关于VLFS研究的发展趋势主要分四个部分：复杂海洋环境中的响应；计算效率的提高；非线性的影响；简单的估计方法的探求。
在本文的研究中，主要使用了直接法。取一正交异性的矩形层合板模型作为研究对象，它由两层单层板组成，长为1000米，宽为500米。将其分为625个小的矩形板单元。在流体部分的计算中采用布源法，求得每个小单元形心处的源强。结构部分的计算采用了4节点矩形单元，通过确定层合板的广义刚度系数得到单元的弹性矩阵，并组成结构的总刚度阵。之后，将水动力附加系数加到结构的刚度阵和质量阵中进行求解。
当然，本文中还有很多不足之处。由于计算机的内存限制，只划分了625个单元，精度上是比较差的。此外在流体与结构的耦合方法上也有可以改进的地方。这些缺憾，如果以后有机会再进行这方面的研究一定会进一步完善。
The research of Very Large Floating Structure(VLFS) started at the end of 80s last century. The first international conference about VLFS was hold in Hawaii of USA at 1991. After that some papers were published. The research about VLFS plays an important role in ITTC and ISSC at present. More than 100 papers will be published all over the world every year. In our country, the first man who brought into contact with this concept is Mr. Wu Yousheng. Moreover, he sent two Doctor, Wang Dayun and Du Shuangxing, to work with researcher of other country using 3-D Hydroelasticity Theory.
The VLFS has three ways of using: as a scientific base; solving the lacking of land; as a martial base.
There are two methods of research about VLFS, direct method and analytical method of mode. Method of mode was used in most of research. The computation of frequency is important as using this method. In later years, the direct method was used gradually. The main developing trend of research about VLFS contains four parts: responses in complicated environment of ocean; enhance the efficiency of computation; influence of non-linear; simple method of estimating about capability.
In my research, direct method was used. I assumed a composite material rectangle model as my studying object, with 1000 meters long and 500 meters wide. It is divided into 625 smaller rectangles. Then I dispose fountainhead in each rectangle. The computation of intensity is using the method of Green function; The computation of the structure was using Finite Element Method. 4-nodes parameter element was used in each structural element. After that, I add hydro-coefficients to the matrix of the structure to compute the displacement.
There are many deficient points in my thesis, such as the precision of computation, the coupling method between liquid and solid, and so on. All of them can be improved in my further research.
超大浮体的用途主要表现在三个方面：作为科研基地，开发海洋资源；作为解决陆地资源匮乏的手段之一。
研究VLFS的方法主要有两种，即直接法和模态分析法。大多数研究中使用的模态分析法，在使用这种方法时频率的计算是很重要的。最近的几年，直接法也逐渐被采用。关于VLFS研究的发展趋势主要分四个部分：复杂海洋环境中的响应；计算效率的提高；非线性的影响；简单的估计方法的探求。
在本文的研究中，主要使用了直接法。取一正交异性的矩形层合板模型作为研究对象，它由两层单层板组成，长为1000米，宽为500米。将其分为625个小的矩形板单元。在流体部分的计算中采用布源法，求得每个小单元形心处的源强。结构部分的计算采用了4节点矩形单元，通过确定层合板的广义刚度系数得到单元的弹性矩阵，并组成结构的总刚度阵。之后，将水动力附加系数加到结构的刚度阵和质量阵中进行求解。
当然，本文中还有很多不足之处。由于计算机的内存限制，只划分了625个单元，精度上是比较差的。此外在流体与结构的耦合方法上也有可以改进的地方。这些缺憾，如果以后有机会再进行这方面的研究一定会进一步完善。
The research of Very Large Floating Structure(VLFS) started at the end of 80s last century. The first international conference about VLFS was hold in Hawaii of USA at 1991. After that some papers were published. The research about VLFS plays an important role in ITTC and ISSC at present. More than 100 papers will be published all over the world every year. In our country, the first man who brought into contact with this concept is Mr. Wu Yousheng. Moreover, he sent two Doctor, Wang Dayun and Du Shuangxing, to work with researcher of other country using 3-D Hydroelasticity Theory.
The VLFS has three ways of using: as a scientific base; solving the lacking of land; as a martial base.
There are two methods of research about VLFS, direct method and analytical method of mode. Method of mode was used in most of research. The computation of frequency is important as using this method. In later years, the direct method was used gradually. The main developing trend of research about VLFS contains four parts: responses in complicated environment of ocean; enhance the efficiency of computation; influence of non-linear; simple method of estimating about capability.
In my research, direct method was used. I assumed a composite material rectangle model as my studying object, with 1000 meters long and 500 meters wide. It is divided into 625 smaller rectangles. Then I dispose fountainhead in each rectangle. The computation of intensity is using the method of Green function; The computation of the structure was using Finite Element Method. 4-nodes parameter element was used in each structural element. After that, I add hydro-coefficients to the matrix of the structure to compute the displacement.
There are many deficient points in my thesis, such as the precision of computation, the coupling method between liquid and solid, and so on. All of them can be improved in my further research.
引文
[1] 刘应中，缪国平．海洋水动力学基础．北京：海洋出版社，1991．
[2] 寿楠椿．弹性薄板弯曲．北京：高等教育出版社，1987。
[3] 费祥麟．高等流体力学．西安：西安交通大学出版社，1989．
[4] 徐芝纶．弹性力学(上、下)．北京：人民教育出版社，1979．
[5] 徐士良．FORTRAN常用算法程序集．北京：清华大学出版社，1992．
[6] 刘岳元．水动力学基础．上海：上海交通大学出版社，1990．
[7] 陈森．弹性力学基础．北京：科学出版社，1981．
[8] 曹富新．简明弹性力学．沈阳：辽宁科学技术出版社，1984．
[9] C．P．汉斯(吴肇之译)．实用薄板理论．北京：人民交通出版社，1982．
[10] 刘式适，刘式达．特殊函数(第二版)．北京：气象出版社，2002．
[11] 金咸定．船体振动学．上海：上海交通大学出版社，1988．
[12] 张汝清，董明．结构计算程序是设计．重庆：重庆出版社，1988．
[13] 沈观林．复合材料力学．北京：清华大学出版社，1996．
[14] 刘更．结构动力学有限元程序设计．北京：国防工业出版社，1993．
[15] 张允真．怎样编写有限元法程序．北京：中国铁道出版社，1990．
[16] 张有天．边界元方法及其在工程中的应用．北京：水利水电出版社，1989．
[17] 龙驭球．有限元法概论．北京：高等教育出版社，1991．
[18] 王新堂．计算结构力学与程序设计．北京：科学出版社，2001。
[19] 饶寿期．有限元法和边界元法基础．北京：北京航空航天大学出版社，1990．
[20] 王世忠．结构力学与有限元法．哈尔滨：哈尔滨工业大学出版社，2003．
[21] 王献孚．计算船舶流体力学．上海：上海交通大学出版社，1992．
[22] 黄祥鹿，陆鑫森．海洋工程流体力学及结构动力响应．上海：上海交通大学出版社，1992．
[23] 洛伦茨．函数逼近论．上海：上海科学技术出版社，1981．
[24] R．M．琼斯(朱颐龄译校)．复合材料力学．上海：上海科学技术出版社，1981．
[25] 罗祖道，李思简．各向异性材料力学．上海：上海交通大学出版社，1994．
[26] R．W．克拉夫，J．彭津(王光远译)．结构动力学．北京：科学出版社，1985．
[27] 陆鑫森．高等结构动力学．上海：上海交通大学出版社，1992．
[28] 蒋孝煜．有限元法基础．北京：清华大学出版社，1992．
[29] 王震鸣．复合材料力学和复合材料结构力学．北京：机械工业出版社，1991．
[30] O. C. Zienkiewicz, R. L. Taylor. The finite element method. 北京：世界图书出版社，2005．
[31] J. N. Newman. Marine Hydrodynamics. The United States of America: Halliday Lithograph Corp, 1977.
[32] J. J. Stoker. Water Waves. New York: New York University, 1966.
[33] 金晶哲，崔维成，刘应中．预报超大型浮体水弹性响应的模态函数展开方法和特征函数展开方法比较．船舶力学．2003，7(4)：86-98．
[34] 崔维成，吴有生，刘应中．超大型浮体水弹性响应分析的力学问题．应用力学进展．2004：395-404．
[35] 孙辉，崔维成，刘应中．超大浮体在二维不均匀底部上的水弹性响应．上海交通大学学报．2003，37(8)：1172-1175．
[36] 闫红梅，崔维成，刘应中．超大型浮体水弹性分析的平板格林函数法．海洋工程．2003，21(4)：8-14．
[37] 崔维成．超大型海洋浮式结构水弹性响应预报的研究现状和发展方向．船舶力学．2002，6(1)：73-90．
[38] 陈徐均，吴有生，崔维成，沈庆．海洋浮体二阶非线性水弹性力学分析的基本理论．船舶力学．2002，6(4)：33-44．
[39] 张淑华，韩满生．用直接法分析超大型浮体的水弹性响应．海洋工程．2004，22(1)：9-18．
[40] 付世晓，范菊，陈徐均，崔维成．考虑浮体弹性变形的锚泊系统分析方法．船舶力学．2004，8(2)：47-54．
[41] 吕海宁，杨建民，姚美旺。箱式超大型浮体在非均匀海洋环境下的水弹性试验．海洋工程．2004，22(1)：1-8．
[42] Takashi Tsubogo. On the dispersion relation of hydroelastic waves in a plate. Journal of Marine Science and Technology. 1999, 4: 76-83.
[43] Qiu Liuchao, Liu Hun. Time domain simulation of transient responses of very large floating structure under unsteady external loads. China Ocean Engineering. 2005, 19(3): 365-374.
[44] Masashi Kashiwagi. A time-domain mode-expansion method for calculating transient elastic responses of a pontoon-type VLFS. Journal of Marine Science and Technology. 2000, 5, 89-100.
[45] Takashi Tsubogo, Koji Masaoka, Hiroo Okada, Yoshisada Murotsu. Simplified estimation for the dynamic behavior and reliability analysis of very large floating structures under wave-induced loads. Journal of Marine Science and Technology. 1999, 4: 84-92.
[46] Masahiko Fujikubo, Taoyun Xiao, Kazuhiro Yamamura. Structural safety assessment of a pontoon-type VLFS considering damage to the breakwater. Journal of Marine Science and Technology. 2003, 7: 119-127.
[47] Masashi Kashiwagi. Transient responses of a VLFS during landing and take-off of an airplane. Journal of Marine Science and Technology. 2004, 9: 14-23.
[48] Shigeo Ohmatsu. Numerical calculation method for the hydroelastic response of a pontoon-type very large floating structure close to a breakwater. Journal of Marine Science and Technology. 2000, 5: 147-160.
[49] X.J.Chen, J.Juncher Jensen, W. C. Cui, S. X. Fu. Hydroelasticity of a floating plate in multidirectional waves. Ocean Engineering. 2003, 30:1997-2017.
[50] Zhang Shuhua, Fujikubo Masahiko. Reliability-based optimal design for very large floating structure. China Ocean Engineering. 2003,17(1):11-19.
[51] Sun Hui, Cui Weicheng, Liu Yingzhong, Liao Shijun. Hydroelastic response analysis of Mat-like VLFS over a plane slope in head seas. China Ocean Engineering. 2003,17(3):315-326.
[2] 寿楠椿．弹性薄板弯曲．北京：高等教育出版社，1987。
[3] 费祥麟．高等流体力学．西安：西安交通大学出版社，1989．
[4] 徐芝纶．弹性力学(上、下)．北京：人民教育出版社，1979．
[5] 徐士良．FORTRAN常用算法程序集．北京：清华大学出版社，1992．
[6] 刘岳元．水动力学基础．上海：上海交通大学出版社，1990．
[7] 陈森．弹性力学基础．北京：科学出版社，1981．
[8] 曹富新．简明弹性力学．沈阳：辽宁科学技术出版社，1984．
[9] C．P．汉斯(吴肇之译)．实用薄板理论．北京：人民交通出版社，1982．
[10] 刘式适，刘式达．特殊函数(第二版)．北京：气象出版社，2002．
[11] 金咸定．船体振动学．上海：上海交通大学出版社，1988．
[12] 张汝清，董明．结构计算程序是设计．重庆：重庆出版社，1988．
[13] 沈观林．复合材料力学．北京：清华大学出版社，1996．
[14] 刘更．结构动力学有限元程序设计．北京：国防工业出版社，1993．
[15] 张允真．怎样编写有限元法程序．北京：中国铁道出版社，1990．
[16] 张有天．边界元方法及其在工程中的应用．北京：水利水电出版社，1989．
[17] 龙驭球．有限元法概论．北京：高等教育出版社，1991．
[18] 王新堂．计算结构力学与程序设计．北京：科学出版社，2001。
[19] 饶寿期．有限元法和边界元法基础．北京：北京航空航天大学出版社，1990．
[20] 王世忠．结构力学与有限元法．哈尔滨：哈尔滨工业大学出版社，2003．
[21] 王献孚．计算船舶流体力学．上海：上海交通大学出版社，1992．
[22] 黄祥鹿，陆鑫森．海洋工程流体力学及结构动力响应．上海：上海交通大学出版社，1992．
[23] 洛伦茨．函数逼近论．上海：上海科学技术出版社，1981．
[24] R．M．琼斯(朱颐龄译校)．复合材料力学．上海：上海科学技术出版社，1981．
[25] 罗祖道，李思简．各向异性材料力学．上海：上海交通大学出版社，1994．
[26] R．W．克拉夫，J．彭津(王光远译)．结构动力学．北京：科学出版社，1985．
[27] 陆鑫森．高等结构动力学．上海：上海交通大学出版社，1992．
[28] 蒋孝煜．有限元法基础．北京：清华大学出版社，1992．
[29] 王震鸣．复合材料力学和复合材料结构力学．北京：机械工业出版社，1991．
[30] O. C. Zienkiewicz, R. L. Taylor. The finite element method. 北京：世界图书出版社，2005．
[31] J. N. Newman. Marine Hydrodynamics. The United States of America: Halliday Lithograph Corp, 1977.
[32] J. J. Stoker. Water Waves. New York: New York University, 1966.
[33] 金晶哲，崔维成，刘应中．预报超大型浮体水弹性响应的模态函数展开方法和特征函数展开方法比较．船舶力学．2003，7(4)：86-98．
[34] 崔维成，吴有生，刘应中．超大型浮体水弹性响应分析的力学问题．应用力学进展．2004：395-404．
[35] 孙辉，崔维成，刘应中．超大浮体在二维不均匀底部上的水弹性响应．上海交通大学学报．2003，37(8)：1172-1175．
[36] 闫红梅，崔维成，刘应中．超大型浮体水弹性分析的平板格林函数法．海洋工程．2003，21(4)：8-14．
[37] 崔维成．超大型海洋浮式结构水弹性响应预报的研究现状和发展方向．船舶力学．2002，6(1)：73-90．
[38] 陈徐均，吴有生，崔维成，沈庆．海洋浮体二阶非线性水弹性力学分析的基本理论．船舶力学．2002，6(4)：33-44．
[39] 张淑华，韩满生．用直接法分析超大型浮体的水弹性响应．海洋工程．2004，22(1)：9-18．
[40] 付世晓，范菊，陈徐均，崔维成．考虑浮体弹性变形的锚泊系统分析方法．船舶力学．2004，8(2)：47-54．
[41] 吕海宁，杨建民，姚美旺。箱式超大型浮体在非均匀海洋环境下的水弹性试验．海洋工程．2004，22(1)：1-8．
[42] Takashi Tsubogo. On the dispersion relation of hydroelastic waves in a plate. Journal of Marine Science and Technology. 1999, 4: 76-83.
[43] Qiu Liuchao, Liu Hun. Time domain simulation of transient responses of very large floating structure under unsteady external loads. China Ocean Engineering. 2005, 19(3): 365-374.
[44] Masashi Kashiwagi. A time-domain mode-expansion method for calculating transient elastic responses of a pontoon-type VLFS. Journal of Marine Science and Technology. 2000, 5, 89-100.
[45] Takashi Tsubogo, Koji Masaoka, Hiroo Okada, Yoshisada Murotsu. Simplified estimation for the dynamic behavior and reliability analysis of very large floating structures under wave-induced loads. Journal of Marine Science and Technology. 1999, 4: 84-92.
[46] Masahiko Fujikubo, Taoyun Xiao, Kazuhiro Yamamura. Structural safety assessment of a pontoon-type VLFS considering damage to the breakwater. Journal of Marine Science and Technology. 2003, 7: 119-127.
[47] Masashi Kashiwagi. Transient responses of a VLFS during landing and take-off of an airplane. Journal of Marine Science and Technology. 2004, 9: 14-23.
[48] Shigeo Ohmatsu. Numerical calculation method for the hydroelastic response of a pontoon-type very large floating structure close to a breakwater. Journal of Marine Science and Technology. 2000, 5: 147-160.
[49] X.J.Chen, J.Juncher Jensen, W. C. Cui, S. X. Fu. Hydroelasticity of a floating plate in multidirectional waves. Ocean Engineering. 2003, 30:1997-2017.
[50] Zhang Shuhua, Fujikubo Masahiko. Reliability-based optimal design for very large floating structure. China Ocean Engineering. 2003,17(1):11-19.
[51] Sun Hui, Cui Weicheng, Liu Yingzhong, Liao Shijun. Hydroelastic response analysis of Mat-like VLFS over a plane slope in head seas. China Ocean Engineering. 2003,17(3):315-326.