Statistical analysis of the influence of cyclic variation on the formation of nitric oxide in spark ignition engines

Journal Article · Thu Jan 01 04:00:00 EST 1976 · Combust. Sci. Technol.; (United States)

DOI:https://doi.org/10.1080/00102207608946712· OSTI ID:7343716

Chen, K K; Krieger, R B

A statistical method is presented to study the influence of cyclic variation of the combustion process on the formation of nitric oxide in spark ignition engines. In the analysis, each engine cycle was treated as a realization of a random experiment. Specifically, the cylinder pressure as a function of crank angle was considered a stochastic process, and the nitric oxide concentration frozen in the expansion stroke was considered a random variable associated with the random experiment. A set of consecutive cylinder pressure-crank angle data furnished the statistical properties of the cylinder pressure of a spark ignition engine at a normal running condition. The stochastic process of cylinder pressure was first approximated by one degree of randomness expression with peak combustion pressure as the characterizing random variable. Secondly, a combustion and nitric oxide kinetics model was used to establish the functional relationship of frozen nitric oxide concentration to cylinder pressure, particularly to the peak combustion pressure. Finally, the probability density function of the nitric oxide concentration was calculated by using the fundamental theorem of functions of random variables.

• Research Organization: General Motors Research Labs., Warren MI
• OSTI ID: 7343716
• Journal Information: Combust. Sci. Technol.; (United States), Journal Name: Combust. Sci. Technol.; (United States) Vol. 12:4/5/6; ISSN CBSTB
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330701* -- Emission Control-- Nitrogen Oxides
CHALCOGENIDES
ENGINES
EXHAUST GASES
GAS COMBUSTION PROCESS
GASEOUS WASTES
INTERNAL COMBUSTION ENGINES
MATHEMATICAL MODELS
MATHEMATICS
NITRIC OXIDE
NITROGEN COMPOUNDS
NITROGEN OXIDES
OXIDES
OXYGEN COMPOUNDS
PRESSURE DEPENDENCE
SPARK IGNITION ENGINES
STATISTICS
WASTES