Predictive Numerical Models and Methods for Selective Catalytic Reactor Applications in Diesel Powered Vehicles

Abstract

The permanently tightening emission legislations especially for NOx pollutants mean new challenges to car manufacturers. A very effective method for reducing NOx emissions in the exhaust gas is available in the framework of selective catalytic reactors, originally developed for coal power plants.
Excellent CFD based methods to predict AdBlue dosing, ammonia uniformity and catalytic reactions have been presented in the past. The aim of this paper is to depict a powerful and efficient method for the simulation of urea-water decomposition. Therefore the two main points discussed here are a detailed decomposition model and efficiency improvements to reduce simulation turnaround time. It will be concluded that a mathematical model to consider solid urea and the deposition is a key point for the successful simulation of an exhaust aftertreatment system. Furthermore, with appropriate efficiency enhancements, simulating minutes of real time becomes affordable. Simulation results are shown to display both the quality of simulation models and methods. The benefits are highlighted and an outlook is given about potential future developments in the field of numerical model development for SCR systems.