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Effects of the Degree of Fuel Atomization on Single-Cylinder Engine Performance
ISSN: 0148-7191, e-ISSN: 2688-3627
Published February 01, 1976 by SAE International in United States
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An investigation has been made to determine the effects of the degree of fuel atomization on exhaust emissions, fuel consumption, lean limit, MBT spark timing, and cyclic variations in peak cylinder pressure. A single-cylinder engine was used to isolate the effects of atomization on combustion from the additional effects of maldistribution that would be present in a multicylinder engine.
Three degrees of gasoline atomization were investigated, along with the case of a well-mixed charge of gaseous propane. The degrees of atomization investigated varied from “Good” (10-20 μm droplets) to “Bad” (400-700 μm droplets) to “Wall-Wetted” (400-700 μm droplets deposited on the intake-port walls).
Results from this investigation show that the degree of atomization can have considerable effect on exhaust emissions, but little effect on fuel consumption. Generally, as atomization deteriorated, hydrocarbon emissions increased; nitric oxide and carbon monoxide emissions increased for certain air-fuel ratio ranges; MBT (Minimum for Best Torque) spark advance decreased; lean limit was extended; and cyclic variations in peak cylinder pressure decreased.
It was hypothesized that the case of Good atomization resulted in an essentially homogeneous charge of vaporized gasoline and air at the time of ignition, while the cases of Bad and Wall-Wetted atomization resulted in in-homogeneous charges; that is, some form of stratification of the fuel-air mixture existed. All of the results are discussed in light of this hypothesis and are shown to be consistent with it.
CitationMatthes, W. and McGill, R., "Effects of the Degree of Fuel Atomization on Single-Cylinder Engine Performance," SAE Technical Paper 760117, 1976, https://doi.org/10.4271/760117.
- Robison J.A. Brehob W.M. “The Influence of Improved Mixture Quality on Engine Exhaust Emissions and Performance,” Journal of the Air Pollution Control Association 17 7 July 1967
- Lindsay R. Thomas A. Woodworth J.A. Zeschmann E.G. “Influence of Homogeneous Charge on the Exhaust Emissions of Hydrocarbons, Carbon Monoxide and Nitric Oxide from a Multicylinder Engine,” SAE Paper No. 710588 Mid-Year Meeting Montreal, Canada June 1971
- Dodd A.E. Wisdom J.W. “Effect of Mixture Quality on Exhaust Emissions from Single-Cylinder Engines,” Proceedings of the Institution of Mechanical Engineers 183 1968
- Quader A.A. “Lean Combustion and the Misfire Limit in Spark Ignition Engines,” SAE Paper No. 741055 Automobile Engineering Meeting Toronto, Canada October 1974
- Mizutani Y. Matsushita S. “Fuel Vapor-Spray-Air Mixture Operation of a Spark-Ignition Engine,” Combustion Science and Technology 8 1973
- Taylor C.F. Taylor E.S. “The Internal Combustion Engine,” International Textbook Co. Scranton, Penn. 1961 34
- Kent J.C. “Quasi-Steady Diffusion Controlled Droplet Vaporization and Condensation,” Applied Science Research 28 1973
- Law C.K. “A Theory for Mono-disperse Spray Vaporization in Adiabatic and Isothermal Systems,” International Journal of Heat and Mass Transfer 18 1975
- Law C.K. “Quasi-Steady Droplet Vaporization Theory with Property Variations,” Physics of Fluids 18 11 1975
- Trayser D.A. Creswick F.A. Gieseke J.A. Hazard H.R. Weiler A.E. Locklin D.W. “A Study of the Influence of Fuel Atomization, Vaporization, and Mixing Processes on Pollutant Emissions from Motor-Vehicle Powerplants,” Report No. PB185886 Battelle Memorial Institute Columbus, Ohio April 30 1969
- “Basic Considerations in the Combustion of Hydrocarbon Fuels with Air,” NACA Report 1300 1959
- Purins E.A. “Pre-Chamber Stratified Charge Engine Combustion Studies,” SAE Paper No. 741159 International Stratified Charge Engine Conference Troy, Michigan 1974
- Lavoie G.A. Blumberg P.N. “Measurements of NO Emissions from a Stratified Charge Engine: Comparison of Theory and Experiment,” Combustion Science and Technology 8 1973
- Blumberg P.N. “Nitric Oxide Emissions from Stratified Charge Engines: Prediction and Control,” Combustion Science and Technology 8 1973
- Blumberg P.N. Kummer J.T. “Predictions of NO Formation in Spark-Ignited Engines -- An Analysis of Methods of Control,” Combustion Science and Technology 4 1971
- Harrington J.A. Shishu R.C. “A Single-Cylinder Engine Study of the Effects of Fuel Type, Fuel Stoichiometry, and Hydrogen-to-Carbon Ratio on CO, NO, and HC Exhaust Emissions,” SAE Paper No. 730476 May 1973
- Patterson D.J. “Cylinder Pressure Variations -- A Fundamental Combustion Problem,” SAE Paper No. 660129 January 1966