Exhaust Emissions Related to Engine Combustion Reactions 660781
Gas sampling and analysis techniques developed for studying preflame reactions were applied to determine combustion chamber formation of inorganic and organic materials found in spark-ignition engine exhaust.
Results show that oxides of nitrogen are flame-formed, decay somewhat in the post flame gases, and then are “frozen” from further decomposition. The exhaust nitrogen oxide concentration is a weighted average of the spatial- and time-dependent combustion chamber concentrations.
Organic exhaust constituents contributed by combustion-chamber slow-combustion reactions were chromatographically found to include olefins, aldehydes, ketones, and ring ethers when operating with isooctane fuel. Addition of TEL to the fuel inhibits slow-combustion reactivity reducing concentrations of slow-combustion products in the exhaust.