Improving the performance and fuel consumption of dual chamber stratified charge spark ignition engines

Technical Report · Sat Sep 01 04:00:00 EDT 1979

DOI:https://doi.org/10.2172/5678567· OSTI ID:5678567

Sorenson, S. C.; Pan, S. S.; Bruckbauer, J. J.; Gehrke, G. R.

A combined experimental and theoretical investigation of the nature of the combustion processes in a dual chamber stratified charge spark ignition engine is described. This work concentrated on understanding the mixing process in the main chamber gases. A specially constructed single cylinder engine was used to both conduct experiments to study mixing effects and to obtain experimental data for the validation of the computer model which was constructed in the theoretical portion of the study. The test procedures are described. Studies were conducted on the effect of fuel injection timing on performance and emissions using the combination of orifice size and prechamber to main chamber flow rate ratio which gave the best overall compromise between emissions and performance. In general, fuel injection gave slightly higher oxides of nitrogen, but considerably lower hydrocarbon and carbon monoxide emissions than the carbureted form of the engine. Experiments with engine intake port redesign to promote swirl mixing indicated a substantial increase in the power output from the engine and, that an equivalent power levels, the nitric oxide emissions are approximately 30% lower with swirl in the main chamber than without swirl. The development of a computer simulation of the combustion process showed that a one-dimensional combustion model can be used to accurately predict trends in engine operation conditions and nitric oxide emissions even though the actual flame in the engine is not completely one-dimensional, and that a simple model for mixing of the main chamber and prechamber intake gases at the start of compression proved adequate to explain the effects of swirl, ignition timing, overall fuel air ratio, volumetric efficiency, and variations in prechamber air fuel ratio and fuel rate percentage on engine power and nitric oxide emissions. (LCL)

• Research Organization: Illinois Univ., Urbana (USA). Dept. of Mechanical and Industrial Engineering
• OSTI ID: 5678567
• Report Number(s): COO-4493-5; UILU-ENG-79-4012
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330101* -- Internal Combustion Engines-- Spark-Ignition
AIR
AIR POLLUTION CONTROL
CHALCOGENIDES
CHEMICAL REACTION KINETICS
COMBUSTION CHAMBERS
COMBUSTION KINETICS
COMBUSTION PRODUCTS
COMPUTERIZED SIMULATION
DATA
DATA FORMS
ENGINES
EXHAUST GASES
EXPERIMENTAL DATA
FLUID FLOW
FLUIDS
FUEL INJECTION SYSTEMS
FUEL SYSTEMS
FUELS
GASEOUS WASTES
GASES
GRAPHS
HYDROCARBONS
INFORMATION
INTERNAL COMBUSTION ENGINES
KINETICS
MIXING
NITROGEN COMPOUNDS
NITROGEN OXIDES
NUMERICAL DATA
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PERFORMANCE
POLLUTION CONTROL
REACTION KINETICS
RESEARCH PROGRAMS
SIMULATION
SPARK IGNITION ENGINES
STRATIFIED CHARGE ENGINES
SWIRL FLOW
THEORETICAL DATA
WASTES