縮小付加質量マトリクスにおける回転ベクトルの影響に関する研究

剛体結合による回転ベクトルの抽出

抄録

For the vibration analysis of floating structures, fluid-structure coupled analysis method which combine the added mass matrix into FEM has been used since many years ago. However, this method has some problems.
In the first problem, it is well known, preparations for FE-model are time consuming works. In second, designers are at a loss how to deliberate the result because too many eigenvalue are obtained. In third problem, the natural frequency in water condition is sometimes different between experiment and calculation though the natural frequency in air condition is equivalent. To solve those problems, reduced added mass matrix method was proposed and this method needed the rotation vector for vibration analysis of higher order modes.
In this paper, the method of extracting rotation vector in experiment is used by rigid connection theory. The modal structural modification analysis is done by using the eigenvectors in 6 directions which contain the extracted rotation vector. This calculation is compared with the experiment in water condition, and the importance of eigenvector on the fluid-structure coupled vibration analysis is shown.