Fluid–structure interaction analysis by optimised boundary element—finite element coupling procedures

In the present work, fluid–structure interaction problems are analysed by means of optimised boundary element–finite element coupling procedures. The boundary element method is here employed to numerically model acoustic fluids and the finite element method is applied to discretise dynamic bodies (nonlinear effects included). Boundary element—finite element coupling is accomplished by an iterative algorithm: each boundary element or finite element sub-domain is analysed independently (as an uncoupled model) and a successive renewal of the variables at the common interfaces is performed, until convergence is achieved. The evaluation of an optimised relaxation parameter is introduced taking into account the minimisation of a square error functional. The algorithm that arises is more efficient and stable, representing an advancement of the iterative procedure. At the end of the paper, numerical examples are presented, illustrating the potentialities of the proposed methodology.