Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Multi-scale modelling by coupling three-dimensional computational fluid dynamics codes with system models

: Bayrasy, P.; Peetz, J.V.; Wolf, K.


Ivanyi, P.:
Proceedings of the Second International Conference on Parallel, Distributed and Grid Computing for Engineering 2011. Vol.1 : Ajaccio, Corsica, France, 12 - 15 April 2011
Red Hook, NY: Curran, 2011 (Civil-Comp proceedings 95)
ISBN: 978-1-617-82743-3
Paper 43, S.628-636
International Conference on Parallel, Distributed, Grid and Computing for Engineering (PARENG) <2, 2011, Ajaccio>
Fraunhofer SCAI ()

MpCCI provides an application independent interface for the coupling of different simulation codes. This facilitates the interaction with the different software and overcomes the version dependencies as well as the complex hardware requirements. Typical MpCCI applications are fluid structure interaction (FSI) and thermal coupling.
Beside those typical applications a generic solution for multi-scale co-simulation has been developed to understand how various simulation models interact with each other and which impact each sub system has on the overall system performance. The MpCCI coupling interface brings together the speed and robustness of the one-dimensional system or functional modelling with the complexity of Three-Dimensional Computational Fluid Dynamics (CFD) enabling system CFD code to be used for the calculations of the entire flow system and the CFD to perform detailed computational calculations.
In a concrete example we will show the need and advantages of such a one-to-three-dimensional combination. The one-to-three-dimensional CFD co-simulation use case couples a one dimensional model of an aircraft environmental control system (ECS) and three quarters of the aircraft passenger cabin with a three dimensional model of the centre section of the passenger cabin. The centre section of the cabin is modelled using the three-dimensional CFD package (Fluent or STAR-CCM), with the co-simulation middleware MpCCI providing coupling adapters to ensure that two-way, bilateral exchange of boundary parameters between the one and the three-dimensional CFD models gives continuity of mass and momentum transfer. Initially the co-simulation server attempts to procure a converged solution with the three-dimensional CFD model. Resultant boundary pressures and, or flow rates at the interface to the one-dimensional model are exchanged with the one-dimensional model so that it may update its solution (generally a quick process) and exchange and update the boundary conditions for the three-dimensional CFD model.
Finally we describe the MpCCI setup for a more generic multi-scale co-simulation. We will present the new upcoming standard for co-simulation in the area of functional and system modelling: Modelisar FMI. The functional mock-up interface (FMI) definition is one result of the ITEA2 project MODELISAR ( The intention is that dynamic system models of different software systems can be used together for software-model-hardware-in-the-loop simulation and for embedded systems. The FMI defines an open interface to be implemented by an executable called functional mock-up unit (FMU).