Full Content is available to subscribers

Subscribe/Learn More  >

NOx Emissions Reduction of a Natural Gas SI Engine Under Lean Conditions: Comparison of the EGR and RGR Concepts

[+] Author Affiliations
Olivier Le Corre

Ecole des Mines de Nantes, Nantes Cedex, France

Frédéric Pirotais

Laboratoire des Ecoulements Géophysiques et Industriels, Grenoble Cedex, France

Paper No. ICES2006-1310, pp. 197-207; 11 pages
  • ASME 2006 Internal Combustion Engine Division Spring Technical Conference
  • ASME 2006 Internal Combustion Engine Division Spring Technical Conference (ICES2006)
  • Aachen, Germany, May 7–10, 2006
  • Conference Sponsors: Internal Combustion Engine Division
  • ISBN: 0-7918-4206-1 | eISBN: 0-7918-3775-0
  • Copyright © 2006 by ASME


In natural gas SI engines under lean conditions, NOx emissions reduction can be realized by injecting an additional mass flow rate to inlet gases. It can be easily done in situ using two techniques: EGR (Exhaust Gas Recirculation) or RGR (Reformed Gas Recirculation) which is an improvement of the usual EGR configuration. Exhaust gases are catalyzed before being reintroduced at the engine inlet. Reformed gases contain carbon monoxide and hydrogen in addition to carbon dioxide, steam and nitrogen dioxide that compose usual recirculated gases. In order to compare EGR and RGR concepts, the study is divided in three stages. Firstly, a “two-zone” thermodynamic model has been developed and validated on a large open chamber SI engine (18L CHP plant engine, fuelled by natural gas and equipped with data acquisition). Both in-cylinder pressure and NOx emissions have been compared between numerical results and experimental data. A good agreement is obtained, the error is less than 3%. Secondly, a widespread model of steam reforming on a Ni/MgOAl2 O3 catalyst has been used to compute in particular CO and H2 concentrations. Numerical results lead to a good concordance with experimental data from literature. Finally, SI engine and reformer models have been linked. RGR and EGR configurations have been numerically compared considering the same recirculation mass flow rate. According to the results, RGR is the best way to decrease significantly nitrous oxide emissions, while keeping good engine performance.

Copyright © 2006 by ASME



Interactive Graphics


Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In