Gasoline Particulate Filter Calibration approach for BS6 market

With the implementation of BS6 standards, there is an increased focus on reducing particulate matter and particulate number emissions from gasoline Direct Injection (GDI) engines. The direct injection process can lead to increased soot formation, which poses environmental concerns. GPFs are effective in capturing particulate matter (PM) and Particulate number (PN) but their calibration is critical to ensure optimal performance and emissions compliance. This paper presents a study on the calibration of Gasoline Particulate Filters (GPF) to comply with Bharat Stage-6 (BS6) emissions norms. The main focus is on thermal management, soot loading, ash loading and the unique challenges faced in the Indian market. Thermal management strategies include active and passive methods to optimize GPF regeneration and prevent thermal degradation. Active RGN mechanism involves advanced control on engine to achieve target temperature and sufficient oxygen to react with soot. Passive RGN occurs during higher load and higher exhaust gas temperature conditions. Soot load detection involves engine-out simulation-based approach as well as delta pressure-based approach for accurate soot modelling. Impact of ash loading and its effects on filtration efficiency and pressure drop will be focused. Further discussion on the strategies to overcome the challenges with respect to variations in driving conditions, ambient conditions and the need for cost-effective solutions ensuring effective GPF calibration for Indian market.