Implicit Coupling of Partitioned Fluid-Structure Interaction Solvers using Reduced-Order Models精编.pdf

Implicit Coupling of Partitioned Fluid-Structure Interaction Solvers using Reduced-Order Models Jan Vierendeels Ghent University, Department of Flow, Heat and Combustion Mechanics, St.-Pietersnieuwstraat 41, B-9000 Ghent, Belgium Abstract. In this contribution a powerful technique is described which allows the strong coupling of partitioned solvers in fluid-structure interaction (FSI) problems. The method allows the use of a black box fluid and structural solver because it builds up a reduced order model of the fluid and structural problem during the coupling process. Each solution of the fluid/structural solver in the coupling process can be seen as a sensitivity response of an applied displacement/pressure mode. The applied modes and their responses are used to build up the reduced order model. The method is applied on the flow in the left ventricle during the filling and emptying phase. Two to three modes are needed, depending on the moment in the heart cycle, to reduce the residual by four orders of magnitude and to achieve a fully coupled solution at each time step. 1 Introduction The computation of fluid-structure interaction (FSI) problems has gain a lot of interest in the past decade. The interaction can be loose or strong. For loose coupling problems (e.g. for flutter analysis [1–3]) existing fluid and structural solvers can be used as partitioned solvers. The main difficulty is the data exchange between those solvers. When strong interaction is present, strong coupling of the fluid and struc- tural solver can be achieved with a monolithic scheme [4]. However parti- tioned schemes can also be used for these applications. Vierendeels et al. [5,6] used a partitioned procedure and reached stabilization of the interac- tion procedure by introducing artificial compressibility in the subiteration