Abstract
In addition to the conventional three-way catalyst (TWC) for CO, NOx, and HC, a gasoline particulate filter (GPF) is now required for filtration of gasoline soot in the exhaust aftertreatment system of gasoline direct injection (GDI) engines. For the space reduction in the engine room especially of hybrid cars which is combined with both an internal combustion engine and a battery-powered electric motor, we need the aftertreatment system coupled with TWC and GPF. However, deposited soot inside the filter may degrade catalytic activity. In this study, by using a lattice Boltzmann method (LBM), we conducted numerical simulations of catalyzed GPF to discuss the effect of soot layer on the conversion rate of TWC. We investigated the effects of the inlet temperature and the filtration velocity on the catalyst performance. Results show that as the inlet temperature is higher or the filtration velocity is lower, the conversion rates of CO, HC and NO are enlarged. When the soot layer is formed on the surface of the filter wall, these conversion rates are all reduced. the filter. These findings would be important for determining the period of filter regeneration.
