POD-GALERKIN METHOD IN FLUID STRUCTURE INTERACTION

This paper describes Reduced Order Modeling (ROM) in Fluid Structure Interaction (FSI) and discusses Proper Orthogonal Decomposition (POD) utilization. In fact to use POD in a moving domain, a reference fixed domain with a fixed uniform grid, is introduced. Next the solution is interpolated from the time-variant grid to the fixed uniform grid to obtain the global velocity field (fluid and structure). Thus PODs modes are obtained for the global velocity field and not only for the fluid velocity. Then a method to reduce dynamical system in rigid body fluid interaction is developed. This method uses the fictitious domain method approach, which consists in treating the entire fluid-solid domain as a fluid by adding a distributed Lagrange multiplier in the weak formulation on solid domain. The method is tested on a two-dimensional ease of rigid body immersed in a fluid. The results are compared with computational solution and discussed.