Transient CFD model of full TWC converter

Abstract

A computational fluid dynamics (CFD) model capable of simulating the cold start transients in a full three way catalytic (TWC) converter is developed by coupling flow and temperature field inside the converter with a detailed chemistry solver. In the proposed model, full TWC chemistry, including oxygen surface coverage based ceria reactions, along with coupled mass transfer is solved using axial integration outside the CFD framework, whereas flow, gas and solid phase energy equations and coverage equations are solved in the CFD framework. The proposed implementation allows direct portability of the kinetics optimized in 1D framework leading to significant reduction in chemistry development time. A CFD converter model developed using the proposed approach leads to 20% reduction in simulation time compared to conventional continuum CFD models. The coupled CFD TWC model is used to predict conversion over the first 150 s of an FTP drive cycle without smoothening the input data.