Effect of Tumble Strength on Combustion and Exhaust Emissions in a Single-Cylinder, Four-Valve, Spark-Ignition Engine

981044

02/23/1998

Event
International Congress & Exposition
Authors Abstract
Content
Direct flame imaging and pressure analysis were applied to the combustion of gasoline and compressed natural gas (CNG) in a single-cylinder, four-valve spark-ignition engine equipped with optical access via quartz windows in the cylinder liner and piston crown. Tests were performed at three engine speed/load conditions and at equivalence ratios of 1.0, 0.9 and 0.8. The four-valve head incorporated two different port geometries, with and without metal sleeves to deflect the intake air flow, in order to investigate the effect of tumble strength on combustion and engine-out emissions of unburned hydrocarbons and NOx. The results showed that sleeving of the intake ports produced a significant increase in IMEP and a reduction in CoV IMEP for both CNG and gasoline, due to the greatly reduced bum duration. Combination of the enhanced tumble induced by the sleeved ports and open valve fuel injection has allowed engine performance with CNG comparable to gasoline but with lower NOx levels and a leaner mixture operating limit.
Meta TagsDetails
DOI
https://doi.org/10.4271/981044
Pages
18
Citation
Arcoumanis, C., Godwin, S., and Kim, J., "Effect of Tumble Strength on Combustion and Exhaust Emissions in a Single-Cylinder, Four-Valve, Spark-Ignition Engine," SAE Technical Paper 981044, 1998, https://doi.org/10.4271/981044.
Additional Details
Publisher
Published
Feb 23, 1998
Product Code
981044
Content Type
Technical Paper
Language
English