Effect of critical dual-carrier structure parameters on performance enhancement of a dual-carrier catalytic converter and the gasoline engine system

The high NO2 concentrations in the gasoline engine exhaust gas are beneficial to improve the regenerative equilibrium performance of the catalytic particulate filter regeneration system. In this work, the effect of critical dual-carrier structure parameters on NO conversion efficiency of the dual-carrier catalytic converter is explored by using the numerical simulation method. The reliable operating temperature range of the dual-carrier catalytic converter under critical dual-carrier structure parameters and the distribution of NO and NO2 mass fraction under the equilibrium state of the catalytic reaction are analyzed. Based on GT-Power software, the variation law of the brake specific fuel consumption (BSFC) and power is studied. The main results are presented as follows: The maximum conversion efficiency of NO is increased from 63% to 67% when the dual-carrier cell density ratios are increased from 300 cpsi/400 cpsi to 500 cpsi/400 cpsi. The maximum NO conversion efficiency of NO is increased from 64% to 66% when the dual-carrier wall thickness ratios are decreased from 0.24 mm/0.17 mm to 0.10 mm/0.17 mm. The maximum conversion efficiency of NO remains about 65% when the dual-carrier length ratios are increased from 30 mm/70 mm to 70 mm/30 mm. The maximum conversion efficiency of NO is increased from 58.5% to 74% when the carrier diameter is increased from 80 mm to 120 mm. And after optimization, the BSFC of the gasoline engine system is reduced by 2% while the power is increased by 7.2%. Finally, some guidelines are proposed to reduce the BSFC and increase the power of the gasoline engine system, while improving the NO conversion efficiency of the dual-carrier catalytic converter.