Abstract
An approximate method is proposed for the analysis of liquid containers considering the effects of the compressibility of the liquid. This method is based on the expansion of the vibration mode of compressible fluid-structure interaction using the coupled modes of incompressible fluid-structure system. Further simplified equations are derived assuming that the vibration modes are not changed when fluid compressibility is included. This paper also shows a technique to avoid the drawback of the mass matrix becoming the full matrix when fluid-structure interaction is considered. It consists of solving simultaneous equations utilizing the sparsity of fluid stiffness matrix without composing the full matrix in the subspace interation method for eigenvalues. Calculated natural frequencies and frequency response spectra, including compressibility of fluid, agree well with experimental results.
