Direct Numerical Simulation of the Flow in an Internal Combustion Engine
The complex flow field in an internal combustion engine has a significant influence on the formation of the fuel-air-mixture in the combustion chamber and on the combustion process itself. Thus, a detailed understanding of the flow field is a necessary condition for a further optimisation of modern combustion engines to increase their efficiency and reduce the pollutant emissions. At the Institute of Aerodynamics of the RWTH Aachen University, numerical methods are developed and GCS supercomputers are used for highly resolved simulations of the flow inside the engine to achieve these goals.
The three figures show exemplary snapshots of the flow field inside an internal combustion engine at different instants of time. Numerous larger and smaller flow structures can be recognised which interact and change in time. For an analysis of the complex flow behaviour, many snapshots of the flow field are generated. These can then for example be used to compute the mean flow field (large figure). While the mean flow field gives information about the large flow structures which are relevant e.g. for the basic design of the engine geometry, the small structures and their behaviour are crucial for the mixing of air and fuel, and the subsequent combustion and pollutant formation.
Dipl.-Ing. Claudia Günther
Aerodynamisches Institut, RWTH Aachen
Wüllnerstraße 5a, D-52062 Aachen