Improving GPF filtration performance through modeling analysis
Xin Liu, Ford Motor Company
Gasoline particulate filter (GPF) has proven to be an effective technology to reduce particle emissions. With increasingly stringent particulate matter emission standards, the need for high GPF filtration performance is growing. Current efforts to improve filtration efficiency mainly focus on fine-tuning the filter structure, such as the pore size distribution and porosity of the bare substrate, or the washcoat loading and location of catalyzed substrates. To quantify the impact of filter structure on filtration efficiency, a capillary tube model is proposed and validated with measured size dependent filtration efficiency data. The key descriptors of the filter structure are further studied through model analysis to evaluate different approaches to improve GPF filtration performance and their tradeoffs.