The absorption and desorption of fuel by cylinder lubricating oil films has been modelled using principles of mass transfer. Henry's Law for a dilute solution of fuel in oil is used to relate gas to liquid phase fuel concentrations. Mass transfer conductances in gas and liquid phases are considered, the former via use of Reynold's Analogy to engine heat transfer data, the latter through assuming molecular diffusion through an effective penetration depth of the oil film.Oxidation of desorbed fuel is assumed complete if the mean of burned gas and lubricating oil film temperatures is greater than 1100K,. Below this value the desorbed fuel is considered to contribute to hydrocarbon emissions.Comparison with engine test data corroborate the absorption/desorption hypothesis. The model indicates the equal importance of gas and liquid phase conductances.
A Model for Absorption and Desorption of Fuel Vapour by Cylinder Lubricating Oil Films and Its Contribution to Hydrocarbon Emissions
Sae Technical Papers
SAE International Congress and Exposition ; 1983
1983-02-01
Aufsatz (Konferenz)
Englisch
Hydrocarbon emissions of SI engines as influenced by fuel absorption-desorption in oil films
Kraftfahrwesen | 1992
|Hydrocarbon Emissions of SI Engines as Influenced by Fuel Absorption-Desorption in Oil Films
SAE Technical Papers | 1992
|Contribution of liquid fuel to hydrocarbon emissions in spark ignition engines
Kraftfahrwesen | 2001
|Contribution of Liquid Fuel to Hydrocarbon Emissions in Spark Ignition Engines
SAE Technical Papers | 2001
|