A numerical study on the effect of CO addition on flame temperature and NO formation in counterflow CH4/air diffusion flames

Download
  1. (PDF, 402 KB)
AuthorSearch for: ; Search for:
TypeArticle
Proceedings titleProceedings of IMECE2007
Conference2007 ASME International Mechanical Engineering Congress and Exposition: November 10-16, 2007, Seattle, Washington, USA
Pages17; # of pages: 7
SubjectDiffusion flame; NOx; Fuel enrichment; Carbon monoxide
AbstractA numerical study was carried out to understand the effect of carbon monoxide enrichment on flame temperature and NO formation in counterflow methane/air diffusion flames. Detailed chemistry and complex thermal and transport properties were employed. The results indicate that when carbon monoxide is added to the fuel, both flame temperature and NO formation rate are changed due to the variations in adiabatic flame temperature, fuel Lewis number and chemical reaction. The combination effects of three factors result in the different characteristics of flame temperature and NO formation at various strain rates, when carbon monoxide is added. At a low strain rate, the addition of carbon monoxide causes a monotonic decrease in flame temperature and peak NO concentration. However, NO emission index first slightly increases, and then decreases. When the value of strain rate is moderate, the addition of carbon monoxide has negligible effect on flame temperature and leads to a slight increase in both peak NO concentration and NO emission index, until the fraction of carbon monoxide reaches about 0.7. Then with a further increase in the fraction of added carbon monoxide, all three quantities quickly decrease. When strain rate is increased to a value close to the strain extinction limit of pure methane/air diffusion flame, the addition of carbon monoxide causes increase in flame temperature and NO formation rate, until a critical carbon monoxide fraction is reached. After the critical fraction, the further addition of carbon monoxide leads to decrease in both flame temperature and NO formation rate. The paper also analyzed the variation in the mechanism of NO formation, when carbon monoxide is added.
Publication date
PublisherASME
LanguageEnglish
AffiliationNRC Institute for Chemical Process and Environmental Technology; National Research Council Canada (NRC-CNRC)
Peer reviewedNo
NRC number51523
NPARC number7632641
Export citationExport as RIS
Report a correctionReport a correction
Record identifier436ce8e0-c3d9-4227-8285-06464b88f28b
Record created2009-10-02
Record modified2016-05-09
Bookmark and share
  • Share this page with Facebook (Opens in a new window)
  • Share this page with Twitter (Opens in a new window)
  • Share this page with Google+ (Opens in a new window)
  • Share this page with Delicious (Opens in a new window)