Implicit coupling of partitioned fluid-structure interaction solvers using reduced-order models

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.