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Liquid Gasoline Behavior in the Engine Cylinder of a SI Engine
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English
Abstract
The liquid fuel entry into the cylinder and its subsequent behavior through the combustion cycle were observed by a high speed CCD camera in a transparent engine. The videos were taken with the engine firing under cold conditions in a simulated start-up process, at 1,000 RPM and intake manifold pressure of 0.5 bar. The variables examined were the injector geometry, injector type (normal and air-assisted), injection timing (open- and closed-valve injection), and injected air-to-fuel ratios.
The visualization results show several important and unexpected features of the in-cylinder fuel behavior: 1) strip-atomization of the fuel film by the intake flow; 2) squeezing of fuel film between the intake valve and valve seat at valve closing to form large droplets; 3)deposition of liquid fuel as films distributed on the intake valve and head region. Some of the liquid fuel survives combustion into the next cycle. The time evolution of the in-cylinder liquid film is influenced by the injection geometry, injection timing, injected air-to-fuel ratio, and port surface temperature. Photographs showing the liquid fuel features and an explanation of the observed phenomena are given in the paper.
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Citation
Shin, Y., Cheng, W., and Heywood, J., "Liquid Gasoline Behavior in the Engine Cylinder of a SI Engine," SAE Technical Paper 941872, 1994, https://doi.org/10.4271/941872.Also In
References
- Cheng, W.K. Hanmrin, D. Heywood, J.B. Hochgreb, S. Min, K-D. Norris, M. “An Overview of Hydrocarbon Emissions Mechanisms in Spark-Ignition Engines,” SAE Paper 932078 1993
- Fox, J.W. Min, K-D. Cheng, W.K. Heywood, J.B. “Mixture Preparation in a SI Engine with Port Fuel Injection During Starting and Warm-up,” SAE Paper 922170 1992
- Namazian, M. Hansen, S.P. Lyford-Pike, E.J. Sanchez-Barsse, J. Heywood, J.B. Rife, J. “Schlieren Visualization of the Flow and Density Fields in the Cylinder of a Spark-Ignition Engine,” SAE Paper 800044 1980
- Yang, J. Kaiser, E.W. Siegl, W.O. Anderson, R.W. “Effects of Port-Injection Timing and Fuel Droplet Size on Total and Speciated Exhaust Hydrocarbon Emissions,” SAE Paper 930711 1993
- Cheng, C.O. Cheng, W.K. Heywood, J.B. Maroteaux, D. Collings, N. “Intake Port Phenomena in a SI Engine at Part Load,” SAE Paper 912401 1991
- Martins, J.J.G. Finlay, I.C. “Fuel Preparation in Port Injected Engines,” SAE Paper 920518 1992