Emission Performance and Durability Validation Methodology for Heavy Commercial Vehicle After-treatment Systems 2022-28-0327

To meet stringent emission norms and commercial vehicle customer demands, the selection of an after-treatment system (ATS) plays a considerable role. Therefore, the selected ATS should substantially reduce nitrogen oxide emission by proper decomposition of ammonia and particulate matter without significantly increasing the thermal stress on DPF. Though the BS-VI after-treatment architecture is derived from EURO-VI, only a certain level of technology for the vehicle operating conditions in India can be implemented. However, numerous vehicle operating condition challenges in the Indian market must be explicated. Correspondingly, it should be addressed with a robust durability validation methodology to enhance the ATS product performance in challenging environments. This paper discusses SCR catalysts emission performance and ammonia decomposition durability validation methodology for commercial vehicles. In addition, during various vehicle duty cycle conditions, the effectiveness of DPF and DOC is recognized based on minimized soot loadings in the DPF based on soot regeneration strategies. Hence, on the one hand, the design of DOC is optimized to recognize passive soot regeneration effectively by oxidation NO into NO₂. On the other hand, for facilitating regeneration temperature (DOC at >500°C) during HC dosing in the exhaust pipe, DOC catalyst effectiveness is also essential. Accordingly, based on the scenario above, the impact of soot loading and back pressure on DPF material durability is also validated for vehicle operating conditions.