HC quench layer formation in combustion processes. Final report

Technical Report · Thu Dec 01 04:00:00 EST 1983

OSTI ID:5448755

Lavoie, G A; Adamczyk, A A

Processes believed responsible for unburned hydrocarbon (HC) emissions in spark-ignition engines have been investigated in a joint study carried out by Ford and the University of Michigan (U-M). Two closely related experiments were performed at Ford and U-M together with an analytical study carried out at U-M. In the experimental work, combustion bombs fitted with identical turbulence generating inlet swirl systems were used to study the effect of turbulence on unburned HC emissions from wall quench and crevices. In the analytical work, a model was developed describing the turbulent wall quench layer in an engine. It also includes the cylinder wall oil-film and ring crevices as additional sources of hydrocarbons which feed into the wall layer after combustion. The results of the studies show that wall quench is not a major source of HC emissions in the bomb and that the effect of increased turbulence on the low emissions from wall quench is to reduce them further. Emissions from crevices introduced into the bomb were found to be more important than those from wall quenching. Turbulence did not greatly affect the HC emissions from the crevices. In the flow studies the gas motion generated by the inlet system on the bombs was found to approximate a solid body rotation with a decay time of 200 msec. High speed schlieren photography was used to observe the flame propagation and the filling and emptying of the crevices. The analytical model compared favorably with experimental engine data and supported the view that oil films and crevices are major sources of hydrocarbons in engine combustion.

• Research Organization: Ford Motor Co., Dearborn, MI (USA)
• DOE Contract Number: AC04-79ET15303
• OSTI ID: 5448755
• Report Number(s): DOE/ET/15303-T7; ON: DE84005068
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330101* -- Internal Combustion Engines-- Spark-Ignition
AIR POLLUTION
BOUNDARY LAYERS
CHEMICAL REACTIONS
COMBUSTION
COMBUSTORS
EMISSION
ENGINES
FLUID FLOW
HEAT ENGINES
HYDROCARBONS
INTERNAL COMBUSTION ENGINES
LAYERS
ORGANIC COMPOUNDS
OXIDATION
POLLUTION
QUENCHING
SPARK IGNITION ENGINES
THERMOCHEMICAL PROCESSES
TURBULENCE