Study on Analysis Variables of Added Mass Effect by Fluid-structure Interaction based on Dynamic Characteristics

In this research, we derive equations related to the fluid-structure interaction of pressure vessels containing fluids from previous research. Moreover, we analyze the changes in the dynamic characteristics based on parameters specified through the dimensions and material properties of the pressure vessel. A fluid is composed of acoustic elements that are adaptable in the frequency domain, and changes in the dynamic characteristics are examined through mode analysis based on the selected parameters. Specifically, the variables selected include the thickness of the fluid compared to the structure, the density, and the stiffness of the pressure vessel. These are selected as the upper and lower limits of the various arrangements of each cylinder and the variation of the material property's value. In conclusion, the smaller the ratio of the thickness of the fluid to the structure, the more noticeable the natural frequency reduction effect (or added mass effect), and it is also confirmed that the change in Young's modulus of the pressure vessel does not contribute to the change in the dynamic characteristics in terms of reducing natural frequencies.