This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Correlating Port Fuel injection to Wetted Fuel Footprints on Combustion Chamber Walls and UBHC in Engine Start Processes
ISSN: 0148-7191, e-ISSN: 2688-3627
Published October 27, 2003 by SAE International in United States
Annotation ability available
Unburned hydrocarbon (UBHC) emissions from gasoline engines remain a primary engineering research and development concern due to stricter emission regulations. Gasoline engines produce more UBHC emissions during cold start and warm-up than during any other stage of operation, because of insufficient fuel-air mixing, particularly in view of the additional fuel enrichment used for early starting. Impingement of fuel droplets on the cylinder wall is a major source of UBHC and a concern for oil dilution.
This paper describes an experimental study that was carried out to investigate the distribution and “footprint” of fuel droplets impinging on the cylinder wall during the intake stroke under engine starting conditions. Injectors having different targeting and atomization characteristics were used in a 4-Valve engine with optical access to the intake port and combustion chamber. The spray and targeting performance were characterized using high-speed visualization and Phase Doppler Interferometry techniques. The fuel droplets impinging on the port, cylinder wall and piston top were characterized using a color imaging technique during simulated engine start-up from room temperature. Highly absorbent filter paper was placed around the circumference of the cylinder liner and on the piston top to collect fuel droplets during the intake strokes. A small amount of colored dye, which dissolves completely in gasoline, was used as the tracer. Color density on the paper, which is correlated with the amount of fuel deposited and its distribution on the cylinder wall, was measured using image analysis. The results show that by comparing the locations of the wetted footprints and their color intensities, the influence of fuel injection and engine conditions can be qualitatively and quantitatively examined. Fast FID measurements of UBHC were also performed on the engine for correlation to the mixture formation results.
CitationKim, H., Yoon, S., Lai, M., Quelhas, S. et al., "Correlating Port Fuel injection to Wetted Fuel Footprints on Combustion Chamber Walls and UBHC in Engine Start Processes," SAE Technical Paper 2003-01-3240, 2003, https://doi.org/10.4271/2003-01-3240.
- Zhao, F. Q. Lai, M. C. Harrington, D. L. “The Spray Characteristics of Automotive Port Fuel Injection - A Critical Review” SAE Paper No. 950506 1995
- Nogi, T. Ohyama, Y. Yamauchi, T. Kuroiwa, H. “Mixture Formation of Fuel Injection Systems in gasoline Engine” SAE Paper No. 880558 1988
- Zhao, F. Q. Yoo, J. H. Lai, M. C. “Spray Targeting Inside a Production-Type Intake Port of a 4-Valve Gasoline Engine” SAE Paper No. 960115 1996
- Yang, J. Kaiser, E. W. Siegel, 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
- Shin, Y. Cheng, W. Heywood, J. B. “Liquid Gasoline Behavior in the Engine Cylinder of a SI Engine,” SAE Paper 941872 1994
- Meyer, R. Heywood, J. B. “Liquid Fuel Transport Mechanisms into the Cylinder of a Firing Port-Injected SI Engine During Start Up” SAE Paper No. 970865 1997
- Takeda, K. Yaegashi, T. Sekiguchi, K. Saito, K. Imatake, N. “Mixture Preparation and HC Emissions of a 4-Valve Engine During Cold Starting and Warm-Up,” SAE Paper 950074 1995
- Witze, P.O. Green, R. M. “LIF and Flame Emission Imaging of Liquid Fuel Films and Pool Fires in an SI Engine During a Simulated Cold Start,” SAE Paper 970866 1997
- Zughyer, J. Zhao, F. Q. Lai, M.-C. Lee, K. “A Visualization Study of Fuel Distribution and Combustion Inside a Port-Injection Gasoline Engine Under Different Start Conditions,” SAE Paper 2000-01-0242 2000
- Lee, S et. al. “Effects of Swirl and Tumble on Mixture Preparation During Cold Start of a Gasoline Direct-Injection Engine,” SAE Paper 2000-01-1900 2000
- Kim, Hoisan Yoon, Suckju Lai, M.-C. “Liquid Fuel Footprints on Combustion Chamber Wall in Port Fuel Injection Engine during Starting,” 9th International Conference on Liquid Atomization and Spray Systems Italy 2003