CFD Simulation of Flow and Temperature inside a monolith of an Exhaust After-Treatment System (EATS)
Examensarbete för masterexamen
Khan, Mohammed Afzal
Internal Combustion Engine is the most popular and efficient types of engine used in the transport sector. On the other hand, it has serious downside in degrading the environmental stability as well. The exhaust gases after the combustion of fuel contain emissions which are harmful for human health and responsible for the climate change. Treating the exhaust gases of an Internal Combustion Engine is a major operation in the vehicle. Exhaust After Treatment System engineering simply known as EATS, can treat and remove these substances from the engine exhaust. Although the applied technology in EATS engineering are already very efficient, it is of interest to gather more knowledge about the velocity and temperature distributions inside the monolith of the reactor during transient operation to further improve the efficiency. By using computer aided simulations to capture the fine details, CFD has become a vital part to gain high resolution data in the monolith channels inside an EATS with the single channel approach. However, due to the computational cost, solving for a complete EATS with high resolution is not yet a possibility. The idea behind this research is to find a small set of channels which can be modelled to represent a complete EATS. Hence, using the single channel approach on the selected channels, these can represent a high resolution EATS simulation. The goal of this project was mainly focusing on obtaining high detailed simulations of ow and temperature for a specially designed monolithic catalytic reactor in transient state. A range of air ow and temperatures were tested in a laboratory, where the ow and temperatures in the inlet and outlet of monolith were recorded. The same ow conditions were reproduced with CFD simulations and a verification for the CFD model was done by comparing these results. A D-optimal algorithm was used on the outlet data of simulated ow tests, to find the optimal four locations for the different cases. Finally, a weighting model was developed where the four locations represent the complete outlet.
Internal Combustion Engine , Exhaust After Treatment System , Computational Fluid Dynamics , Design of experiments , D-Optimal analysis etc.