From Detailed to Real-time Exhaust Aftertreatment Models

Stringent emissions regulations along with the need for cost and time reduction has increased the reliance on Software-in-the-Loop (SiL) and Hardware-in-the-Loop (HiL) simulations to optimize aftertreatment components and control algorithms. HiL and SiL applications require the derivation of reduced models which are capable of running real-time and at the same time preserve a sufficient degree of accuracy with respect to the detailed model. This paper presents a methodology for the development, application and validation of a real-time surrogate model of a diesel oxidation catalyst (DOC) and a selective catalytic reduction (SCR) catalyst. A detailed kinetic model is executed for a wide range of operating points and the generated results are used for the training of the surrogate model. The performance and accuracy of the surrogate model, compared to the detailed model, is evaluated under random conditions and transient driving cycles.