Most technical products are an assembly of different systems. In product design, simulation is a well established tool in order to accelerate the development-to-market time. For a lot of physical phenomena sophisticated simulation tools exist, e.g. for fluids Computational Fluid Dynamics (CFD) or for structures Computational Solid Mechanics (CSM). A product usually consists of systems which may be modeled in different dimensions i.e. the coupling of ordinary differential equations (ODEs) and partial differential equations (PDEs) is required. For instance the simulation of a car requires a CSM solver to reproduce the structural behavior. Moreover, the simulation of the flow around the car necessitates the use of a CFD solver. The CSM and CFD solver need to resolve all four dimensions, i.e. three spatial and time dimensions to accurately model the physics. Other components like sensor or actors (e.g. hydraulic system of the brakes) may be modeled with two dimensions, i.e. one spatial and one time. Thus the CSM and CFD solver need to be coupled to the solvers which represent the sensors and actors. A concept for this kind of Co-Simulation is presented where in contrast to Fluid-Structure Interaction the number of simulation tools is larger than two. Furthermore, the presented concept accounts for the coupling of PDE and ODE systems. The motivation for Co-Simulation (also called partitioned coupling) is the high flexibility and reusability of existing simulation tools. The presented framework is based on a client-server approach where MPI-2 functionality is used to implement socket-like communication between the client and the server. The dataflow handling inside the server program is done dynamically, hence the dataflow is determined at runtime. The presented approach can also handle non-matching discretizations and is suited for very large simulations involving a large number of unknowns. The software concept is illustrated by interfacing OpenFOAM® with the in-house coupling tool called EMPIRE (Enhanced MultiPhysics Interface Research Engine) to various other simulation tools. By this OpenFOAM® capabilities can be extended to very complex simulation scenarios involving a large number of different physical phenomena e.g. nonlinear CSM with control. The goal is to provide a flexible concept for coupling different simulation tools with different dimensions in an efficient and accurate way.     «

Most technical products are an assembly of different systems. In product design, simulation is a well established tool in order to accelerate the development-to-market time. For a lot of physical phenomena sophisticated simulation tools exist, e.g. for fluids Computational Fluid Dynamics (CFD) or for structures Computational Solid Mechanics (CSM). A product usually consists of systems which may be modeled in different dimensions i.e. the coupling of ordinary differential equations (ODEs) and par...     »