Engine air path management and exhaust condition modeling in Dymola

In order to comply with increasing consumer and regulatory demand for improved fuel economy and lower emissions, the engines and engine aftertreatment systems must be improved continuously. Since the complete system is very complex, models are useful in order to be able to cost efficiently develop new control strategies and selection of hardware. In this article, a model library for dynamic engine modeling in Dymola is presented. The library consists of models of the standard engine components such as manifolds, pipe, turbines, compressors, valves and mechanics. The combustion model is a mean value model and the focus has been on air path management and exhaust modeling with real-time-like simulation times, useful for engine optimization and for evaluation of control strategies. Engine simulation results from a 13-L Volvo engine demonstrates that the models capture the dynamics and have sufficient accuracy to be useful in engine optimization.