This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
The Importance of Injection System Characteristics on Hydrocarbon Emissions from a Direct-Injection Stratified-Charge Engine
Annotation ability available
Sector:
Language:
English
Abstract
The effects of injection variability, low velocity fuel injection, and injector orifice size on unburned hydrocarbon emissions were studied in a direct-injection stratified-charge (DISC) engine. The engine incorporated a combustion process similar to the Texaco Controlled Combustion System (TCCS) and was operated with gasoline. The variability in the amount of fuel injected per cycle was found to have a negligible effect on HC emissions. Changing the amount of fuel injected at low velocity at the end of injection impacted the HC emissions by up to 50%. A positive pressure differential between the injection line and the combustion chamber when the injector needle closed resulted in more fuel injected at low velocity and increased HC emissions. High speed single frame photography was used to observe the end of injection. Injectors with smaller orifices had substantially lower HC emissions than the baseline injector. Smaller injector orifices favored lower emissions because of both lower residence times of unburned fuel in the combustion chamber and a lower portions of the fuel injected at low velocity at the end of injection. These studies were done without considering the constraint of satisfactory operability over the full load and speed range of the engine. They suggest that a solution to the high HC emissions from the DISC engine at low loads can be found with improvements to the injection system to span high and low power operation without degradation in the injection process.
Authors
Citation
Frank, R. and Heywood, J., "The Importance of Injection System Characteristics on Hydrocarbon Emissions from a Direct-Injection Stratified-Charge Engine," SAE Technical Paper 900609, 1990, https://doi.org/10.4271/900609.Also In
References
- Giovanetti, A.J. “Analysis of Hydrocarbon Emissions Mechanisms in a Direct -Injection Spark-Ignition Engine,” Dept. of Mechanical Engineering, M.I.T. 1982
- Giovanetti, A.J. Ekchian, J.A. Heywood, J.B. Fort, E.F. “Analysis of Hydrocarbon Emissions Mechanisms in a Direct Injection Spark-Ignition Engine,” SAE Paper 830587 SAE Trans 92 1983
- Wood, C.D. “Unthrottled Open-Chamber Stratified Charge Engines,” SAE paper 780341 1978
- Haslett, R.A. Managhan, M.L. McFadden, J.J. “Stratified Charge Engines,” SAE paper 760755 1976
- Abata, D. “A Review of Stratified Charge Engine Concept,” Automotive Engine Alternatives Int'l Symposium on Alternative and Advanced Automotive Engines 1986
- Alperstein, M. Schafer, G.H. Villforth, F.J. “Texaco's Stratified Charge Engine - Multifuel, Efficient, Clean, and Practical,” SAE paper 740563 1974
- Mitchell, E. Alperstein, M. Cobb, J.M. Faist, C.H. “A Stratified Charge Multifuel Military Engine - A Progress Report,” SAE paper 720051 1972
- Lewis, J.M. “UPS Multifuel Stratified Charge Engine Development Program - Field Test,” SAE paper 860067 1986
- Lewis, J.M. McBride, T.K. “UPS Multifuel Stratified Charge Engine Development - Progress Report,” SAE paper 831782 SAE Trans . 92 1983
- Lewis, J.M. Tierney, W.T. “United Parcel Service Applies Texaco Stratified Charge Engine Technology to Power Parcel Delivery Vans - Progress Report,” SAE paper 801429 SAE Trans . 89 1980
- Siewert, R.M. Groff, E.G. “Unassisted Cold Starts to -29°C and Steady State Tests of a Direct-Injection Stratified-Charge (DISC) Engine Operated on Neat Alcohols,” SAE paper 872066 1987
- Kim, C. Foster, D.E. “Aldehyde and Unburned Fuel Emission Measurements from a Methanol-Fueled Texaco Stratified-Charge Engine,” SAE paper 852120 SAE Trans . 94 SP- 638 1985
- Frank, R.M. “Sources of Unburned Hydrocarbon Emissions from a Direct-Injection Stratified-Charge Engine,” Dept. of Mechanical Eng., M.I.T. 1989
- Gatowski, J. A. Balles, E. N. Chun, K. M. Nelson, F. E. Ekchian, J. A. Heywood, J. B. “Heat Release Analysis of Engine Pressure Data,” SAE paper 841359 SAE Trans . 93 1984
- Chun, K. M. Heywood, J. B. “Estimating Heat-Release and Mass-of- Mixture Burned from Spark-Ignition Engine Pressure Data,” Combust. Sci. Technol. 54 133 144 1987
- Woschni, G. “A Universally Applicable Equation for the Instantaneous Heat Transfer Coefficient in the Internal Combustion Engine,” SAE paper 670931 SAE Trans . 76 1967
- Sihling, K. Woschni, G. “Experimental Investigation of the Instantaneous Heat Transfer in the Cylinder of a High Speed Diesel Engine,” SAE paper 790833 1979
- Young, M. B. Lienesch, J. H. “An Engine Diagnostic Package (EDPAC) - Software for Analyzing Cylinder Pressure-Time Data,” SAE paper 780967 1978
- Balles, E.N. Ekchian, J.A. Heywood, J.B. “Fuel Injection Characteristics and Combustion Behavior of a Direct-Injection Stratified-Charge Engine,” SAE paper 841379 SAE Trans . 93 1984
- Solomon, A. “A Photographic Study of Fuel Spray Ignition in a Rapid Compression Machine,” SAE paper 860065 SAE Trans . 95 1986
- Tolan, L.E. Hess, T.D. “The Pencil Nozzle - Past, Present, & Future,” SAE paper 830666 1983
- Collings, N. “A New Technique for Measuring HC Concentrations in Real Time in a Running Engine,” SAE paper 880517 1988
- Frank, R.M. Heywood, J.B. “Combustion Characterization in a Direct-Injection Stratified-Charge Engine and Implications on Hydrocarbon Emissions,” SAE paper 892058 1989
- Greeves, G. Khan, I.M. Wang, C. H. T Fenne, I. “Origins of Hydrocarbon Emissions from Diesel Engines,” SAE paper 770259 SAE Trans . 86 1977
- Ford, H.S. Merrion, D.F. Hames, R.J. “Reducing Hydrocarbons and Odor in Diesel Exhaust by Fuel Injector Design,” SAE paper 700734 1970
- Yu, R.C. Kuo, T.-W. Shahed, S.M. Chang, T.W. “The Effect of Mixing Rate, End of Injection, and Sac Volume on Hydrocarbon Emissions from a D.I. Diesel Engine,” SAE paper 831294 SAE Trans . 92 1983
- Arai, M. Tabata, M. Hiroyasu, H. Shimizu, M. “Disintegrating Process and Spray Characterization of Fuel Jet Injected by a Diesel Nozzle,” SAE paper 840275 SAE Trans . 93 1984
- Beer, J.M. Chigier, N.A. Combustion Aerodynamics Krieger Publishing Co. 1983
- Bracco, F.V. “Modeling of Engine Sprays,” SAE paper 850394 SAE Trans . 94 1985
- Norris-Jones, S.R. Russell, J.T. “‘FM’ - High Efficiency Combustion System for the Future Light Duty Engine?,” SAE paper 820760 SAE Trans . 91 1982
- Ewing, P. “Orbital Technologies for the Future Vehicle,” Energy 85 Conference Sydney, Australia 1985
- Lefebvre, A.H. Gas Turbine Combustion 14 15 Hemisphere Publishing Corp. 1983