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Flame Lift-Off on Direct-Injection Diesel Sprays Under Quiescent Conditions
ISSN: 0148-7191, e-ISSN: 2688-3627
Published March 05, 2001 by SAE International in United States
Annotation ability available
Event: SAE 2001 World Congress
Ambient gas temperature and density, injection pressure, and orifice diameter effects on the flame lift-off length on a direct-injection (DI) diesel spray under quiescent conditions were experimentally investigated. The impacts of the observed lift-off length variations on air entrainment upstream of the lift-off location, soot formation, and the relationship between fuel vaporization and combustion were also examined. The research was conducted in a constant-volume combustion vessel using a common-rail fuel injector and a Phillips research grade #2 diesel fuel.
The lift-off length measurements show that lift-off length decreases with increasing ambient gas temperature or density, and increases with increasing injection pressure or orifice diameter. The sensitivity of lift-off length to a change in either temperature or density was non-linear, with the sensitivity to either parameter decreasing as it increased. The increase in lift-off length with increasing injection pressure was linearly dependent on injection velocity. Estimates of the air entrainment upstream of the lift-off length, show that the amount of fuel-air pre-mixing upstream of the lift-off length is dependent on the combined effects of many of the above mentioned parameters on air entrainment and the lift-off length. Coupling the air entrainment estimates with soot incandescence measurements indicates that there is a strong link between the fuel-air mixing upstream of the lift-off length and soot formation. Soot incandescence was observed to decrease as the amount of fuel-air premixing upstream of the lift-off length increased, with no significant soot incandescence (i.e., no significant soot) being observed when enough air was entrained to reduce the average equivalence ratio at the lift-off length to a value less than approximately two. Finally, comparison of the lift-off lengths with previously measured liquid lengths indicates that the relationship between fuel vaporization and combustion is strongly affected by ambient gas and injector parameters.
CitationSiebers, D. and Higgins, B., "Flame Lift-Off on Direct-Injection Diesel Sprays Under Quiescent Conditions," SAE Technical Paper 2001-01-0530, 2001, https://doi.org/10.4271/2001-01-0530.
- Rothrock, A.M. and Waldron, C.D., “Effect of Nozzle Design on Fuel Spray and Flame Formation in a High-Speed Compression-Ignition Engine,” T R No 561, NACA, 1936.
- Shundoh, S., Kakegawa, T., and Tsujimura, K., “The Effect of Injection Parameters and Swirl on Diesel Combustion with High Pressure Fuel Injection” Transactions of the SAE, Vol. 100, Sec. 3, pp. 793-805, 1991.
- Verhoeven, D., Vanhemelryck, J., and Baritaud, T., “Macroscopic and Ignition Characteristics of High-Pressure Sprays of Single-Component Fuels,” Transactions of the SAE, Vol. 107, Sec. 3, pp. 1654-1668, 1998.
- Dec, J.E., “A Conceptual Model of DI Diesel Combustion Based on Laser-Sheet Imaging,” Transactions of the SAE, Vol. 106, Sec. 3, pp. 1319-1348, 1997.
- Naber, J.D. and Siebers, D.L., “Effects of Gas Density and Vaporization on Penetration and Dispersion of Diesel Sprays,” Transactions of the SAE, Vol. 105, Sec. 3, pp. 82-111, 1996.
- Chomiak, J. and Karlsson, A., “Flame Liftoff in Diesel Sprays,” Twenty-Sixth Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, pp. 2557-2504, 1996.
- Flynn, P.F., Durrett, R.P., Hunter, G.L., zur Loye, A.O., Akinyemi, O.C., Dec, J.E., and Westbrook, C.K., “Diesel Combustion: An Integrated View Combining Laser Diagnostics, Chemical Kinetics, and Empirical Validation,” SAE1999-01-0509, 1999.
- Kalghatgi, G.T., “Lift-off Heights and Visible Flame Lengths of Vertical Turbulent Jet Diffusion Flames in Still Air,” Combustion Science and Technology, Vol. 41, pp. 17-19, 1984.
- Pitts, W.M., “Importance of Isothermal Mixing Processes to the Understanding of Lift-Off and Blowout of Turbulent Jet Diffusion Flames,” Combustion and Flame, Vol. 76, pp. 197-312, 1989.
- Tacke, M.M., Geyer, D., Hassel, E.P., and Janicka, J., “A Detailed Investigation of the Stabilization Point of Lifted Turbulent Diffusion Flames,” Twenty-Seventh Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, pp. 1157-1165, 1998.
- Hasselbrink E.F. Jr., and Mungal, M.G., “Characteristics of the Velocity Field Near the Instantaneous Base of Lifted Non-Premixed Turbulent Jet Flames,” Twenty-Seventh Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, pp. 867-873, 1998.
- Brockhinke, A., Andresen, P., and Kohse-Höinghaus, K., “Contributions to the Analysis of Temporal and Spatial Structures Near the Lift-Off Region of a Turbulent Hydrogen Diffusion Flame,” Twenty-Sixth Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, pp. 153-159, 1996.
- Schefer, R.W., Namazian, M., and Kelly, J., “Stabilization of Lifted Turbulent-Jet Flames,” Combustion and Flame, Vol. 99, pp. 75-86, 1994.
- Schefer, R.W., Namazian, M., Filtopoulos, E.E.J., and Kelly, J., “Temporal Evolution of Turbulence/Chemistry Interactions in Lifted, Turbulent-Jet Flames,” Twenty-Fifth Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, pp. 1223-1231, 1994.
- Peters, N., Turbulent Combustion, Cambridge University Press, Cambridge, UK, 2000.
- Winklhofer, E., Fuchs, H., and Philipp, H., “Diesel Spray Combustion - An Optical Imaging Analysis,” Transactions of the SAE, Vol. 102, Sec. 3, pp. 1154-1163, 1993.
- Larsson, A., “Optical Studies in a DI Diesel Engine,” SAE1999-01-3650, 1999.
- Higgins, B.S. and Siebers D.L., “Measurement of the Flame Lift-off Location on DI Diesel Sprays Using OH Chemiluminescence,” SAE2001-01-0918, 2001.
- Siebers, D.L. and Higgins, B.S., “Effects of Injector Conditions on the Flame Lift-Off Length of DI Diesel Sprays,” Conference on Thermalfluidynamic Processes in Diesel Engines, Sept. 14-15, 2000.
- Siebers, D.L., “Liquid-Phase Fuel Penetration in Diesel Sprays,” Transactions of the SAE, Vol. 107, Sec. 3, pp. 1205-1227, 1998.
- Siebers, D.L., “Ignition Delay Characteristics of Alternative Diesel Fuels: Implications on Cetane Number,” Transactions of the SAE, Vol. 94, Sec. 7, pp. 673-686, 1985.
- Oren, D.C., Wahiduzzaman, S., and Ferguson, C.R., “A Diesel Combustion Bomb: Proof of Concept,” Transactions of the SAE, Vol. 93, Sec. 5, pp. 945-960, 1984.
- Durrett, R.P., Oren, D.C., and Ferguson, C.R., “A Multidimensional Data Set for Diesel Combustion Model Validation: I-Initial Conditions, Pressure History and Spray Shapes,” SAE872087, 1987.
- Siebers., D.L., “Scaling Liquid-Phase Fuel Penetration in Diesel Sprays Based on Mixing-Limited Vaporization,” SAE1999-01-0528, 1999.
- Naber, J.D., Siebers, D.L., Caton, J.A., Westbrook, C.K., and Di Julio, S.S., “Natural Gas Autoignition Under Diesel Conditions: Experiments and Chemical Kinetic Modeling,” Transactions of the SAE, Vol. 103, Sec. 4, pp. 1735-1753, 1994.
- Naber, J.D. and Siebers, D.L., “Hydrogen Combustion Under Diesel Engine Conditions,” International Journal of Hydrogen Energy, Vol. 23, No. 5, pp. 363-371, 1998.
- Gaydon, A.G., The Spectroscopy of Flames, Chapman and Hall Ltd., London, 1974.
- Crosley, D.R. and Dryer, M.J., “Two-Dimensional Imaging of Laser-Induced Fluorescence in OH in a Flame,” Proceedings of the International Conference on Lasers, Dec., 1982.
- Kosaka, H., Nishigaki, T., Kamimoto, T., Sano, T., Matsutani, A., and Harada, S., “Simultaneous 2-D Imaging of OH Radicals and Soot in a Diesel Flame by Laser Sheet Techniques,” Transactions of the SAE, Vol. 105, Sec. 3, pp. 1184-1195, 1996.
- Heywood, J., Internal Combustion Engines, McGraw-Hill, New York, 1988.
- Dec J.E. and Espey, C., “Soot and Fuel Distributions in a D.I. Diesel Engine via 2-D Imaging,” Transactions of the SAE, Vol. 101, Sec. 4, pp. 1642-1651, 1992.
- Kamimoto, T., Yokota, H., and Kobayashi, H., “Effect of High Pressure Injection on Soot Formation Processes in a Rapid Compression Machine to Simulate Diesel Flames,” Transactions of the SAE, Vol. 96, Sec. 4, pp. 4.783-4.791, 1987.
- Canaan, R.E., Dec, J.E., and Green, R.M., “The Influence of Fuel Volatility on the Liquid-Phase Fuel Penetration in a Heavy-Duty D.I. Diesel Engine,” Transactions of the SAE, Vol. 107, Sec. 3, pp. 583-602, 1998.