New ways to symmetrise free vibration equations of fluid–structure interaction systems

It can be difficult to use finite-element (FE) analyses to solve fluid–structure interaction due to asymmetric equivalent mass and stiffness matrices. Based on mathematical calculations, two new techniques are proposed to achieve a symmetric eigenvalue problem. For this purpose, new scale matrices to symmetrise the interaction system's eigenproblem are presented. Numerical FE analysis of a liquid-storage tank proves the validity and efficiency of the proposed techniques compared with other existing approaches, providing higher convergence rate and lower analysis time.