A rapid acting sampling valve to obtain gas samples directly from the combustion chamber of a running diesel engine was developed concurrently with a mathematical model for the formation of NO in diesel engines, based on the extended Zeldovich mechanism. The temporal and spacial distribution of NO and the local air fuel ratio were determined in each case. The model depended heavily on the information provided by the gas samples which, in conjunction with high speed photography of the combustion process, indicated that NO was formed only in gases exposed to high temperature flame and that any NO found in cooler areas of fresh air or weaker mixture appeared there solely by mixing the hot gases, despite the high oxygen concentration. In addition the delay between the combustion and the appearance of NO is clearly shown and this allowed considerable simplification of the model in that only the reactions involved in NO formation needed to be considered kinetically in order to give good correlation between experimental and theoretically predicted exhaust NO content over most of the engine operating range.

  • Supplemental Notes:
    • Presented at a meeting held Sept. 8-11, 1975.
  • Corporate Authors:

    Society of Automotive Engineers (SAE)

    400 Commonwealth Drive
    Warrendale, PA  United States  15096
  • Authors:
    • Nightingale, D R
  • Publication Date: 1975

Media Info

  • Features: References;
  • Pagination: 17 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00129084
  • Record Type: Publication
  • Source Agency: Engineering Index
  • Report/Paper Numbers: 750848 Preprint
  • Files: TRIS
  • Created Date: Feb 4 1976 12:00AM