Study on Hydroelastic Behavior of a Veyr Large Floating Structure in Waves

Veyr大型漂浮结构在波浪中的水弹性行为研究

• 批准号: 08651103
• 负责人: KASHIWAGI Masashi
• 金额: $ 1.54万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08651103/
• 关键词: Very large floating structure; Hydroelasticity; B-spline function; Galerkin method; Mode expansion method; Direct method; Pressure distribution method; モード分解法

The purpose of the present project was to develop a practical but accurate method of calculating the hydroelastic responses of a very large floating structure (VLFS) in short waves. This purpose was almost achieved, and the results are summarized as follows :1) The method is based on the pressure distribution method. The unknown pressure under a VLFS is expressed with bi-cubic B-spline functions, and the Galerkin method is employed for satisfying the body boundary condition. The computation time is extremely reduced by adopting " relative similarity relations" in computing the matrix coefficients. Singular integrals originating from a Rankinesource Part of the Green function are evaluated ahalytically, which also contributes to the good accuracy with fewer unknowns.2) The hydroelastic responses are calculated by both the mode expansion method and the direct method. ln the mode-expansion method, computed results are confirmed to converge smoothly as the number of modes increases. In the direct method, bi-cubic B-spline functions are used for representing both the pressure and structural deflection, which is simple in coding the scheme. Comptuted results of the deflection are in good agreement with experiments.

本项目的目的是开发一种实用而准确的方法来计算短波中超大型浮动结构（VLFS）的水弹性响应。这个目的基本达到了，结果总结如下：1）该方法基于压力分布法。 VLFS下的未知压力用双三次B样条函数表示，并采用Galerkin方法来满足体边界条件。在计算矩阵系数时采用“相对相似关系”，大大减少了计算时间。源自朗肯源的奇异积分对格林函数的一部分进行了解析计算，这也有助于在未知数较少的情况下获得良好的精度。2）通过模态展开法和直接法计算水弹性响应。在模式扩展方法中，计算结果被证实随着模式数量的增加而平滑地收敛。直接法中，采用双三次B样条函数来表示压力和结构挠度，格式编码简单。偏转计算结果与实验吻合良好。

项目成果

Kashiwagi, M.: "AB-Spline Galerkin Scheme for Calculating Hydroelastic Response of a Very Large Floating Structure in Waves" Journal of Marine Science and Technology(to be published). (1998)

Kashiwagi, M.：“用于计算波浪中超大型浮动结构的水弹性响应的AB样条伽辽金方案”海洋科学与技术杂志（待出版）。

柏木 正: "超大型浮体構造物の波浪中弾性応答" 九州大学応用力学研究所所報. 82. 31-52 (1997)

Tadashi Kashiwagi：“波浪中超大型浮动结构的弹性响应”九州大学应用力学研究所报告 82. 31-52 (1997)。

Kashiwagi, M.: "AB-Spline Galerkin Scheme for Computing Wave Forces on a Floating Very Large Elastic Plate" Proc.7th International Offshore and Polar Engineering Conference(Honolulu). 1. 229-236 (1997)

Kashiwagi, M.：“用于计算浮动超大弹性板上波浪力的 AB 样条伽辽金方案”Proc.7th 国际近海和极地工程会议（檀香山）。

Kashiwagi, M.: "A Calculation Method of Hydrodynamic Forces on a Shallow-Draft and Very Large Floating Structure" Proc.of Techno-Ocean, 96 International Conference(Kobe). Vol.2. 627-632 (1996)

Kashiwagi, M.：“浅吃水和超大型浮动结构上的水动力计算方法”Proc.of Techno-Ocean，96 国际会议（神户）。

M.Kashiwagi: "A B-Spline Galerkin Scheme for Calculating Hydroelastic Response of a Very Large Floating Structure in Waves" Jounnal of Marine Science and Technology. (印刷中).

M. Kashiwagi：“用于计算波浪中非常大的浮动结构的水弹性响应的 B 样条伽辽金方案”海洋科学与技术杂志（正在出版）。