An Innovative Coupling Scheme of FEM And BEM Solvers

A Multi-System Interface Coupling Technique (MSIC) has been developed for coupling Boundary Element Method (BEM) and Finite Element Method (FEM) solutions in the direct time domain for linear elasticity and wave propagation problems. The MSIC allows for independent selection of time step in each of the solvers and has been shown to be highly accurate, stable and efficient. This work focuses on the development of a master solver that controls and couples, without iterations or solution staggering, the solvers of the independent systems in the direct time domain. The proposed method is based on substructuring concepts but adopts an explicit enforcement of displacement compatibility and force equilibrium at the interface boundary among the systems in an innovative and efficient manner. The master solver operates at a time step independent of the solvers of the systems, obtains required data from each system solver and performs operations to couple the systems at their interfaces and solve for global responses.