U자형 탱크 구조의 진동특성에 관한 연구

Abstract

Recently, ship and marine structures are more complex and lager, there exists various shape tank structures. Especially, there are a lot of tanks filled with fresh water, sea water and fuel oil in the structures, so added mass effects drop the natural frequency of structures. Because these tanks always have resonance possibility with exciting forces of engine, propeller, wave, and sloshing, etc. It is very important to predict the precise vibration characteristic of the tank structures at the design stage. Until now, simple type tanks like rectangular and cylindrical tanks have been studied by many researchers. Rectangular and cylindrical tanks in contact with fluid have been studies by chiba(2000) and etc. Bae(2003) analyzed the plates of rectangular tank using FEM(finite element method) and fluid region using BEM(boundary element method). Lakis(2008) experimented two cases. One case is the horizontal plate and the other is the perpendicular plate. But any shape tanks like U-shape have not been studied. The goal of this study is to find out the vibration characteristics of the U-shape tank. First, experimental mode analysis is carried out about the U-shape tank idealizing anti-rolling tank. After comparing experimental results with FEM results for verification of FEM, the U-shape tank is analyzed as follows dimension(length, width, height) of the tank are changed to consider various conditions. Second, multi plates coupled with fluid are analyzed to find out other results.