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The introduction of more stringent standards for engine emissions requires a steady development of exhaust gas aftertreatment in addition to an optimized cylinder combustion. The reduction of the cold start phase can help significantly to lower cycle emissions. With the goal of optimizing the overall emission performance this study presents a comprehensive simulation approach. A well established 1D gas dynamics and engine simulation model is extended by three key features. These are models for combustion and pollutant production in the cylinder, models for the pollutant conversion in a catalyst, and a general species transport model. This allows to consider an arbitrary number of chemical species and reactions in the entire system.

The present work introduces a real-time capable crank-angle resolved engine model to test control strategies offline and online on Hardware-in-the-Loop environments. In order to follow a consistent modeling tool chain, the real-time model is derived from a detailed 1D cycle simulation and gas exchange model. Identical model parameters, applied in both approaches for the major engine components, cylinder and turbo-charger, help avoid time consuming re-parameterization and validation of isolated models used in different phases of the engine development process. Appropriate numerical schemes are applied to associate accuracy requirements with computational time constraints. The real-time model is validated by comparing cylinder traces with results gained from the 1D model for a turbo-charged diesel engine. The transient responses of both models are compared during vehicle driving conditions.