Sebastian Krittian, Torsten Schenkel1, Ralf Kröger, Uwe Janoske, Herbert Oertel Universität Karlsruhe (TH), Germany, ANSYS Fluent, Darmstadt, Germany, BA Mosbach, Germany

at MpCCI UF 2008

The focus of this work is on the application of a partitioned coupling scheme between Fluent and Abaqus using the code coupling interface MpCCI. However, for the chosen structural and fluid dynamic software combination MpCCI's current algorithms are restricted to a so-called explicit coupling where the data exchange is executed only once per time-step. This kind of coupling tends to numerical instabilities for critical values of fluid density, structural density and stiffness. These circumstances play an important role when simulating e.g. blood flow in bio-fluid mechanics or hydro-elasticity phenomena in general. For the first time, an implicit coupling, i.e. an iterative coupling procedure during one time-step is realised for the software combination Fluent, Abaqus and MpCCI. This process is controlled by new-developed Fluent FSI subroutines and new Fluent command sequences executing MpCCI’s standard version. As far as Abaqus is concerned the current implementation is restricted to static structural input. In order to gain a converged unsteady result either load or node position relaxation can be chosen which influences the data flow between Fluent and Abaqus or vice versa. Relaxation values and further parameters can be entered easily in a new-developed Fluent GUI panel.