Characterizing Nox Emissions from Diesel Trucks with Tampered Aftertreatments and its Implications for Identifying High Emitters

• DOI: 10.2139/ssrn.4625818
• Publication Date: 2023-11-07T10:20:31Z
• Authors: Miao Tian; Liqiang He; Di Peng; Mingliang Fu; Shuai Ma; Jinsong Mu; Quanshun Yu; Jia Wang; Hang Yin; Junfang Wang

The discrepancy between real-world and certificated NOx emission levels makes it very crucial for in-use surveillance. Therefore, investigating the characteristics of vehicles which have much higher emissions (i.e., high-emitters) determining a reasonable cut-off point with low false detection rate is important. In this study, six diesel trucks were tested under different aftertreatment conditions. results showed that discrepancies fuel-specific functioning tampered selective catalytic reduction (SCR) occur mainly from medium- to high-speed modes. Furthermore, similar factors derived during cold-start operation without SCRs, indicating efficiency was over phase. By using binary classification, we selected points high-emitters China V VI trucks. can decrease by 33% 95%, if only modes used chosen points, respectively. This work highlights importance compliance programs. It also suggests be more accurately identified at instantaneous data.