This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Characterization of Knock in a Spark-Ignition Engine
ISSN: 0148-7191, e-ISSN: 2688-3627
Published February 01, 1989 by SAE International in United States
Annotation ability available
Spark-ignition engine knock was characterized in terms of when during the engine cycle and combustion process knock occurred and its magnitude or intensity. Cylinder pressure data from a large number of successive individual cycles were generated from a single-cylinder engine of hemispherical chamber design over a range of operating conditions where knock occurred in some or all of these cycles. Mean values and distributions of following parameters were quantified: knock occurrence crank angle, knock intensity, combustion rate and the end-gas thermodynamic state. These parameters were determined from the cylinder pressure data on an individual cycle basis using a mass-burn-rate analysis. The effects of engine operating variables on these parameters were studied, and correlations between these parameters were examined.
The individual cycle knock occurrence crank angle correlates well with the combustion rate or a thermodynamic parameter representing the end-gas temperature history on an individual cycle basis. But the individual cycle knock intensity does not correlate with any of the relevant variables measured although the mean knock intensity did correlate well with the mean unburned fuel fraction at knock. This lack of correlation on an individual cycle basis is thought to be due to differences in the end-gas temperature and species concentration distributions, and differences in the geometry and location of the end-gas region, cycle-by-cycle.
CitationChun, K. and Heywood, J., "Characterization of Knock in a Spark-Ignition Engine," SAE Technical Paper 890156, 1989, https://doi.org/10.4271/890156.
- Ricardo, H.R. “Some Early Reminiscences,” SAE Trans. 63 620 627 1955
- Amann, C.A. “Classical Combustion Diagnostics for Engine Research,” SAE paper 850395 1985
- Leppard, W.R. “Individual-Cylinder Knock Occurrence and Intensity in Multicylinder Engines,” SAE paper 820074 1982
- Kono, M. Shiga S. Kumagai S. Iinuma K. “Thermodynamic and Experimental Determination of Knock Intensity by Using a Spark-Ignited Rapid Compression Machine,” Combustion and Flame 54 1983
- Takagi, Yasuo Itoh, T. Iijima, T. “An Analytical Study on Knocking Heat Release and Its Control in a Spark Ignition Engine,” SAE paper 880196 1988
- Chun, K.M. Heywood, J.B. “Estimating Heat-Release and Mass-of-Mixture Burned from Spark-Ignition Engine Pressure Data,” Combustion Sci. and Tech. 1987 54 133 143
- Lee, W. Schaefer, H.J. “Analysis of Local Pressures, Surface Temperatures and Engine Damages under Knock Conditions,” SAE paper 830508 SAE Trans. 92 1983
- Nakagawa, Y. Takagi, Y. Itoh, T. Iijima, T. “Laser Shadowgraphic Analysis of Knocking in S.I. Engine,” SAE paper 845001 XX FISITA Congress Proceedings P-143 1984
- Spicher, U. Kollmeier, H.-P. “Detection of Flame Propagation During Knocking Combustion by Optical Fiber Diagnostics,” SAE paper 861532 1986
- zur Loye A.O. Bracco F.V. “Two-Dimensional Visualization of Premixed-Charge Flame Structure in an IC Engine,” SAE paper 870454 1987
- Beretta, G.P. Rashidi, M. Keck, J.C. “Turbulent Flame Propagation and Combustion in Spark Ignition Engines,” Combustion and Flame 52 217 245 1983