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The pressure drop as well as the overall lifetime of wall flow diesel particulate filters is strongly influenced by the capability of storing non-combustible ash. One approach to reach low pressure drops and long filter lifetimes is the application of optimized channel geometries. This study presents a comprehensive simulation approach for filters with asymmetrical channel structures in the presence of soot and ash. The wall flow model, soot loading and regeneration approaches are discussed with all model equations. The soot filtration model distinguishes between the regimes of depth and cake filtration. The regeneration model takes into account soot regeneration reactions, catalytically supported soot reactions and catalytic wall reactions. The simulated pressure drop of filters with different channel diameters at different operating conditions is compared to measured values. The predicted pressure drop due to depth and cake filtration is compared to experimental data.

The present work introduces an innovative mechanistically based 0D spray model which is coupled to a combustion model on the basis of an advanced mixture controlled combustion approach. The model calculates the rate of heat release based on the injection rate profile and the in-cylinder state. The air/fuel distribution in the spray is predicted based on momentum conservation by applying first principles. On the basis of the 2-zone cylinder framework, NOx emissions are calculated by the Zeldovich mechanism. The combustion and emission models are calibrated and validated with a series of dedicated test bed data specifically revealing its capability of describing the impact of variations of EGR, injection timing, and injection pressure. A model based optimization is carried out, aiming at an optimum trade-off between fuel consumption and engine-out emissions. The findings serve to estimate an economic optimum point in the NOx/BSFC trade-off.

The present work introduces an extended particulate filter model focusing on capabilities to cover catalytic and surface storage reactions and to serve as a virtual multi-functional reactor/separator. The model can be classified as a transient, non-isothermal 1D+1D two-channel model. The applied modeling framework offers the required modeling depth to investigate arbitrary catalytic reaction schemes and it follows the computational requirement of running in real-time. The trade-off between model complexity and computational speed is scalable. The model is validated with the help of an analytically solved reference and the model parametrization is demonstrated by simulating experimentally given temperatures of a heat-up measurement. The detailed 1D+1D model is demonstrated in a concept study comparing the impact of different spatial washcoat distributions.