Computer Simulation of Automotive Emission Control Systems

摘要

Computer simulation has become an important tool for designing automotive emission control systems. This paper highlights some of the key developments made in modelling of diesel emissions control components and catalysts by Johnson Matthey. The general methodology for model development involves determination of the reaction kinetics using laboratory reactor data, followed by validation of the resulting model against vehicle or engine data. The development of models for diesel oxidation catalysts (DOCs), ammonia selective catalytic reduction (SCR) catalysts, lean nitrogen oxides (NOx) traps (LNTs) and diesel particulate filters (DPFs), including coated filters such as the SCR coated DPF (SCRF?), is discussed.A new methodology for developing models (or at least adapting existing models) using engine or vehicle data, which offers a faster route to a finished model, is also discussed. The use of this methodology to develop a DOC model capable of predicting the effect of platinum group metal (pgm) loading is presented; the model gives a good prediction of carbon monoxide, hydrocarbon (HC), NOx and nitrogen dioxide (NO2) over a vehicle test cycle for pgm loadings in the range 30 g ft–3 to 120 g ft–3.