Simulation of a Nonisothermal Modern Three-Way Catalyst Converter

Abstract

A two-dimensional (2D) nonisothermal monolith reactor model based upon intrinsic detailed reaction kinetics has been developed to simulate the performance of a commercial modern three-way catalytic converter. The model directly employed the reliable kinetic parameters estimated from the detailed reaction kinetics determined over the powder-type three-way catalysts (TWCs). The TWC activity of the monolith reactor containing each Pd and Pt/Rh/Ce catalyst with respect to the catalyst mileages, 4k miles (stabilized) and 100k miles (aged) equivalent aged by engine-dynamometer, has been examined in a molten-salt bath under the steady-state condition. To simulate the commercial performance of a modern TWC converter, both reactor models specifically developed for the Pd (front) and Pt/Rh/Ce (rear) monoliths have been sequentially integrated on the basis of the commercial configuration of the monolith reactors in a dual-bed mode. The 2D nonisothermal monolith reactor model developed in the present study well predicts the TWC performance, including the gas compositions and the temperature distribution with respect to both axial and radial positions of the single-bed containing each individual catalyst monolith as well as of the dual-bed monolith reactor system including both Pd (front) and Pt/Rh/Ce (rear) monolith bricks. The reactor model was further validated by predicting the TWC performance of the dual-bed reactor under the steady-state sweep test (st-ST) condition varying the A/F ratios from 14.23 to 15.03 with respect to the reaction temperature.