LEAN COMBUSTION AND THE MISFIRE LIMIT IN SPARK IGNITION ENGINES

A study was undertaken to understand what causes very lean mixtures to misfire in engines. Results showed that leaner operation was possible with improved mixture preparation, increased airflow, decreased nitrogen (N2) dilution, increased compression ratio, increased mixture temperature, decreased engine speed, more central spark location, and multiple spark plugs. The dominant factors responsible for these effects were mixture homogeneity, charge dilution, and charge temperature. In most cases, at the lean limit the combustion duration (in crank angle degrees) reached a limiting value. The significance of these findings together with the exhaust emission and fuel consumption results are presented and discussed.

Media Info

  • Pagination: 20 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00084975
  • Record Type: Publication
  • Report/Paper Numbers: SAE Paper #741055
  • Files: TRIS
  • Created Date: May 1 1975 12:00AM