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A Study of Knock in Lean-Burn Spark-Ignition Engines
ISSN: 0148-7191, e-ISSN: 2688-3627
Published September 01, 1992 by SAE International in United States
Annotation ability available
A study on the onset of knock in dilute spark-ignition engines was conducted on a Ricardo E6 variable compression engine. The combustion chamber was of the disc type providing the very basic shape of chambers. Various operating parameters were considered viz: equivalence ratio, engine speed, ignition timing, inlet air temperature and inlet air pressure. The onset of knock was defined by a piezo-electric pressure transducer while knock was characterized by ‘knock-limited compression ratio’. In some experiments, perforated disc-type turbulence generators with different blockage ratios were fitted immediately before the inlet valve; the object being to enhance in-cylidner turbulence and thus the effect of such turbulence augmentation on knock limit was experimentally defined. Correlations were developed to enable the onset of knock to be predicted which read:
for a gasoline with an octane number of 90. and
for a gasoline with an octane number of 80.
CitationRadwan, M., "A Study of Knock in Lean-Burn Spark-Ignition Engines," SAE Technical Paper 921668, 1992, https://doi.org/10.4271/921668.
- Ferraro, C.V. Marzano M. Nuccio P. knock-limit measurement in high speed S.I. engines SAE 850127 1985 SAE Intl. Congress and exposition Detroit, MI Feb. 25 mar. 1 1985
- Iwata, T. Sakakibara K. Haraguchi H. New method to automatically optimize the knock detection level in the knock control system SAE 881 780 1988 SAE passenger car meeting and exposition Oct. 31 Nov. 3 1988
- Cuttler, D.H. Girgis N.S. Photography of combustion during knocking cycles in disc and compact chambers SAE 880195 1988 SAE Intl. Congress and exposition Detroit, MI Feb. 29 Mar. 4 1988
- Hamiroune, D. Hoult D.P. The role of end gas heat transfer in knock calculations SAE 880197 1988 SAE Intl. Congress and exposition Detroit, MI. Feb. 29 Mar. 4 1988
- Takagi, Y. Itoh T. Iijima T. knocking analysis quantifies relationship between burned mass rate, mixture fraction burned by autoignition and knocking intensity SAE 880196 1988 SAE Intl. Congress and exposition Detroit, MI Feb. 29 Mar. 4 1988
- Schäpertöns, H. Lee W. Multidimensional modelling of knocking combustion SAE 850502 1985 SAE Intl. Congress and exposition Detroit Feb. 25 Mar. 1 1985
- Douaud, A.M. Eyzat P. Four-octane number method for predicting the anti-knock behaviour of fuels and engines SAE paper 780080 SAE Trans. 87 1978