Center for Environmental Research and Technology

Pengfei Fan, a Ph.D. candidate in the School of Traffic and Transportation at Beijing Jiaotong University and currently a visiting scholar at CE-CERT, will give a seminar on Tuesday, January 21st entitled: Real-World Dynamics of SCR Temperature and Their Effects on NOx Emission Control in HDDVs

Abstract: Nitrogen oxide (NOx) emissions from heavy-duty diesel vehicles (HDDVs) are a major source of air pollution, contributing to significant environmental and health issues. Although Selective Catalytic Reduction (SCR) systems are widely implemented to reduce engine-out NOx emissions, their efficiency is highly dependent on temperature. Under optimal conditions, SCR systems can reduce more than 90% of NOx emissions. However, in real-world driving scenarios, factors such as cold starts, extended idling, and frequent stops often cause SCR temperatures to drop below the optimal range (200–300 °C), leading to substantial decreases in Denitrification (DeNOx) efficiency and elevated NOx emissions. Our recent research focuses on quantifying SCR temperature fluctuations and their impact on NOx emissions during real-world operations. Large-scale vehicle operating data, including SCR temperature and NOx emission measurements, were collected from five in-use HDDVs under various vocational uses. The findings provide insights into the key factors influencing SCR temperature drops and highlight the importance of accounting for these variations when modeling real-world emissions. These results offer valuable guidance for improving emission reduction strategies and enhancing the accuracy of regulatory emission models.

Bio: Pengfei Fan is a Ph.D. candidate in the School of Traffic and Transportation at Beijing Jiaotong University and currently a visiting scholar at CE-CERT. His research interests include energy consumption and emissions modeling, transportation electrification, and sustainable mobility. He primarily leverages big data and machine learning techniques to analyze environmental and energy issues in transportation systems. Pengfei has published research papers in high-impact journals such as Transportation Research Part D: Transport and Environment and Energy Policy. During his visit, he worked closely with Dr. Kanok Boriboonsomsin on research focused on NOx emission characteristics and energy consumption of trucks under real-world operating conditions, accounting for dynamic factors such as vehicle weight, road grade, and SCR temperature variations. They also investigated the electrification potential of trucks in different vocational sectors and assessed the associated emission reduction benefits.

His recent work focuses on improving real-world emission models and developing strategies for zero-emission vehicle adoption, with a particular emphasis on assessing energy supply infrastructure for electric truck fleets. Pengfei is actively seeking postdoctoral opportunities to further pursue research in transportation electrification, emission control, and sustainable transportation systems. Over the course of his academic career, he has received multiple awards, including the Chinese National Scholarship and the Outstanding Graduate Student Innovation Project Award. In addition to publishing in high-impact journals, he has actively participated in international conferences and served as a peer reviewer for several leading journals and conferences in the fields of transportation and environmental research. Pengfei holds a B.Sc. and M.Sc. in Transportation Engineering from Beijing Jiaotong University and expects to complete his Ph.D. by June 2025.