A novel hybrid spectral element-boundary element (SEM-BEM) method for the hydroelastic vibration analysis of shells in contact with fluid

Coupled or hybrid finite element-boundary element methods (FEM-BEM) are widely employed for hydroelastic vibration analysis of elastic structures in contact with fluid. In such frameworks, due to the convergence characteristics and computational cost, the discretization in finite element analysis is different, in general, than that used in boundary element analysis, at the fluid–structure interface. As a result, a mapping step is required between the two domains to analyze the overall fluid–structure interaction problem, leading to an increased computational complexity. In this study, a novel hybrid spectral element-boundary element method (SEM-BEM) is presented to provide a computationally-efficient framework circumventing the mapping issue in the classical approaches. The proposed framework establishes a direct coupling between the two computational domains, leveraging the higher order accuracy of spectral elements for the structural domain and the dimensional reduction of boundary elements for the fluid domain. To this end, a Chebyshev spectral element method is developed to predict the dynamic characteristics under in vacuo condition, while a boundary element method is employed to determine the fluid–structure interaction effects. The applicability of the proposed SEM–BEM framework is demonstrated through a number of numerical examples, which validate the accuracy of the method and highlight its favorable convergence characteristics.