The Impact of Exhaust Gas Recirculation on Performance and Emissions of a Heavy-Duty Diesel Engine Conference Paper uri icon


  • This work studies the complex interactions resulting from the application and control of Exhaust Gas Recirculation (EGR) on a production heavy-duty diesel engine system, and its effectiveness in reducing NOx emissions. The coupling between EGR, the Variable Geometry Turbocharger (VGT) and the EGR cooler critically affects boost pressure, air/fuel ratio (A/F), combustion efficiency and pumping work. It is shown that EGR provides an effective means for reducing flame temperatures and NOx emissions, particularly under low A/F ratio conditions. However, engine thermal efficiency tends to decrease with EGR as a result of decreasing indicated work and increasing pumping work. Combustion deterioration is predominant at higher load, low speed and low boost conditions, due to a significant decrease of A/F ratio with increasing EGR. For conditions allowing the VGT to maintain high enough boost and hence A/F ratio, efficiency losses with increased EGR are largely attributed to increased pumping work. Finally, the total system heat rejection increases significantly due to EGR cooling Copyright 2003 SAE International.

name of conference

  • SAE Technical Paper Series

published proceedings

  • SAE Technical Papers

author list (cited authors)

  • Jacobs, T., Assanis, D. N., & Filipi, Z.

citation count

  • 116

complete list of authors

  • Jacobs, Timothy||Assanis, Dennis N||Filipi, Zoran

publication date

  • December 2003