Combustion analysis and cycle-by-cycle variations in spark ignition engine combustion Part 2: A new parameter for completeness of combustion and its use in modelling cycle-by-cycle variations in combustion

Ball, Jeffrey K.; Raine, Robert R.; Stone, C. R.

doi:10.1243/0954407981526145

Cited by 33 publications

(27 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…By comparing the two cases, it is observed that in lean operating conditions, the impact of the ignition timing on the indicated mean effective pressure is higher compared to the stoichiometric mixture, an observation which is in agreement with other studies [2][3][4][5][6][7][8][9]. From these data it seems that cycle-to-cycle combustion variability is more pronounced in lean and highly diluted mixtures, even with slight modification of the combustion parameters.…”

Section: Effect Of Engine Operation Parameters On Emissionssupporting

confidence: 88%

“…In most CCV analysis, only the thermodynamic data are measured, without considering the emission data. Ball et al (1998) [4] used experimental data from a Rover K4 optical engine to investigate cycle-to-cycle variation in combustion and NO emissions. The fuel used in those experiments was methane.…”

Section: Experimental Datamentioning

confidence: 99%

“…The fuel used in those experiments was methane. That engine from the Ball et al (1998) [4] work was simulated in the present study, as many engine specifications necessary for the modeling are contained in that publication and are summarized in Table 2. The model was applied to this engine and the results of the …”

Section: Experimental Datamentioning

confidence: 99%

“…The Rover K4 was simulated with the AVL BOOST model for mean cycle Wiebe parameters and the results A. Karvountzis-Kontakiotis and L. Ntziachristos / Investigation of Cycle-to-Cycle Variability of NO in Homogeneous Combustion were compared with the experimental cycle-averaged engine data found in Ball et al (1998) [4]. The comparison between experimental and simulated data refers to the imep, the maximum pressure during the combustion phase, the crank-angle degree where maximum pressure occurs, and the crank angle degree where 10% of the fuel mass is burned (MFR).…”

Section: Mean Cycle No Modelingmentioning

confidence: 99%

“…Experimentally, Cycle-to-Cycle Variability (CCV) is best observed by the scatter of the measured cylinder pressure around the mean pressure curve. Such fluctuations of the cylinder pressure have an impact on engine performance [1], fuel consumption [2] and pollutant emissions [3,4], while in some extreme cases such as highly diluted lean mixtures could result in misfiring or knocking [2]. The Coefficient Of Variation of the indicated mean effective pressure (COV imep ) is used for the classification of CCV [5].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Investigation of Cycle-to-Cycle Variability of NO in Homogeneous Combustion

Karvountzis-Kontakiotis

Ntziachristos

2014

Oil Gas Sci. Technol. – Rev. IFP Energies nouvelles

View full text Add to dashboard Cite

-Cyclic variability of spark ignition engines is recognized as a scatter in the combustion parameter recordings during actual operation in steady state conditions. Combustion variability may occur due to fluctuations in both early flame kernel development and in turbulent flame propagation with an impact on fuel consumption and emissions. In this study, a detailed chemistry model for the prediction of NO formation in homogeneous engine conditions is presented. The Wiebe parameterization is used for the prediction of heat release; then the calculated thermodynamic data are fed into the chemistry model to predict NO evolution at each degree of crank angle. Experimental data obtained from literature studies were used to validate the mean NO levels calculated. Then the model was applied to predict the impact of cyclic variability on mean NO and the amplitude of its variation. The cyclic variability was simulated by introducing random perturbations, which followed a normal distribution, to the Wiebe function parameters. The results of this approach show that the model proposed better predicts mean NO formation than earlier methods. Also, it shows that to the non linear formation rate of NO with temperature, cycle-to-cycle variation leads to higher mean NO emission levels than what one would predict without taking cyclic variation into account.Re´sume´-Enqueˆte de la variabilite´cycle-a`-cycle du NO dans la combustion homoge`neLa variabilite´cyclique des moteurs a`allumage commande´est reconnue comme une dispersion dans les enregistrements des parame`tres de combustion lors du fonctionnement re´el dans des conditions stables. Des variabilite´s de combustion peuvent se produire en raison des fluctuations dans le de´veloppement pre´coce du noyau de la flamme et dans la propagation turbulente de la flamme avec un impact sur la consommation de carburant et les e´missions. Cette e´tude pre´sente un mode`le chimique de´taille´pour pre´voir la formation de NO dans des conditions de combustion homoge`ne. Le parame´trage de Wiebe est utilise´pour pre´voir le de´gagement de chaleur ; les donne´es thermodynamiques calcule´es sont ensuite inte´gre´es au mode`le chimique pour pre´voir l'e´volution de NO a`chaque degre´d'angle de rotation du vilebrequin. Les donne´es expe´rimentales obtenues a`partir de l'analyse des publications ante´rieures ont e´te´utilise´es pour valider les niveaux moyens de NO calcule´s. Le mode`le a ensuite e´te´applique´pour pre´voir l'impact de la variabilite´cyclique sur le taux moyen de NO forme´et l'amplitude de sa variation. La variabilite´cyclique a e´te´simule´e en introduisant des perturbations ale´atoires qui suivent une distribution normale, aux parame`tres de la fonction de Wiebe. Les re´sultats de cette approche montrent que le mode`le propose´pre´dit mieux le taux moyen de formation de NO que les me´thodes pre´ce´dentes. Les re´sultats montrent e´galement qu'une vitesse de formation non line´aire de NO avec la tempe´rature et la variation cyclea`-cycle, entraıˆne une moyenne plus e´lev...

show abstract