Load and motion transfer algorithms for fluid/structure interaction problems with non-matching discrete interfaces: Momentum and energy conservation, optimal discretization and application to aeroelasticity

The prediction of many fluid/structure interaction phenomena requires solving simultaneously the coupled fluid and structural equations of equilibrium with an appropriate set of interface boundary conditions. In this paper, we consider the realistic situation where the fluid and structure subproblems have different resolution requirements and their computational domains have non-matching discrete interfaces, and address the proper discretization of the governing interface boundary conditions. We present and overview new and common algorithms for converting the fluid pressure and stress fields at the fluid/structure interface into a structural load, and for transferring the structural motion to the fluid system. We discuss the merits of these algorithms in terms of conservation properties and solution accuracy, and distinguish between theoretically important and practically significant issues. We validate our claims and illustrate our conclusions with several transient aeroelastic simulations. (C) 1998 Elsevier Science S.A.