Vibration analysis of fiuid-structure interaction problem (1st report; Analytical procedure using boundary element method and modal analysis technique)

This paper presents the numerical procedure for solving the fluid-structure interactive vibration of a three dimensional structure with complicated configuration such as ship structures, offshore structures and so on. This numerical analysis procedure consists of the following three steps. (a) Experiment or finite element numerical code enables us to obtain the preliminary dynamic characteristics of the structure without fluid inertia effect or with lumped added mass approximating the fluid inertia effect. (b) Boundary element method determines the added mass matrix of fluid surrounding the structure whose surface has three dimensional and complicated configuration. (c) Model analysis technique combines the added mass matrix of fluid with the preliminary dynamic characteristics of the structure and leads to obtain the final results of fluid-structure interactive vibration. In the case of using the preliminary result with approximated lumped mass, lumped mass is to be subtracted from the added mass matrix of fluid.