Fuel and Combustion

Fuel and Combustion

Evaluation of Various Knock Control Methods in a Spark Ignition Engine Fuelled with Natural Gas through a Three Zone Quasi-Dimensional

Authors
1 Faculty of Mechanical Engineering, K. N. Toosi University of Technology, Tehran, Iran
2 Faculty of Aerospace Engineering, K. N. Toosi University of Technology, Tehran, Iran
Abstract
Detection of knock onset to control abnormal combustion is one of the most important targets in SI engine modeling. The present contribution describes a refined analytical approach to knock occurrence simulation and its intensity. In the quasi-dimensional model used in this research, the homogeneous charge of the cylinder during the combustion period is assumed to be divided into three parts; These include: burned product, unburned reactant, which comprises the end gas region, and flame front. One of the advantages of this research is its application of turbulent flame propagation to mass burning rate estimation and its use of kinetic reactions mechanism in both burned and unburned zones. A 32 step- and 14 species- mechanism is applied to examine the behavior of the end gas region. Finally, operating parameters, factors affecting knock onset and its intensity (e.g. inlet pressure and temperature, equivalence ratio, spark timing, compression ratio, etc.) have been examined. Moreover, the effects of EGR on knock occurrence and engine output are evaluated as an effective method, and are compared against other factors. The predictive engine model has been validated through comparing the calculated results with the experimental data from an actual engine, and the results show a significant agreement between the two.
Keywords

1.     Kowalewicz, A., and Wojtyniak, M., “A Comparison of Combustion Characteristics of Waste Cooking Oil with Diesel as Fuel in a Direct Injection Diesel Engine,” Proc. IMech. Engrs, Part D: J. Automobile Engineering, 219, pp. 103–125, 2004.
2.     Natural Gas at a Glance, Secondary Energy Information Book, pp. 28-31, USA, 2007.
3.     Stone, R., Introduction to Internal Combustion Engines, Society of Automotive Engineers, Second Edition, 1993.
4.     Ramos, J. I., Internal Combustion Engine Modeling, Hemisphere Publishing Corporation, First Edition, 1989.
5.     Hajireza, S., Sunden, B., and Mauss, F., “A Three Zone Model for Investigation of Gas Behavior in the Combustion chamber of SI Engines in Relation to Knock,” SAE Paper No. 1999-01-0219, 1999.
6.     Konig, G., and Sheppard, C. G. W., “End-Gas Auto-Ignition and Knock in a Spark Ignition Engine,” SAE Paper No. 902135, 1990.
7.     Ghanbari, M., Jazayeri, S. A., and Ebrahimi R., “A Refined Analytical Combustion Model for Evaluating the Effects of EGR Percentage on Improvement of Knock Characteristics of Natural Gas in Spark Ignition Engine,” ASME World Congress, IMECE2008-68607, Boston, USA, 2008.
8.     Ibrahim, A., and Bari, S., “Optimization of Natural Gas SI Engine Employing EGR Strategy Using a Two Zone Combustion Model,” J. of Fuel, 87, Issues 10-11 , pp. 1824-1834, 2008.
9.     Williams, F. A., “Turbulent Combustion,” SIAM, Philadelphia, 1985.
10.  Shrestha, S. O., and Karim, G. A., “A Predictive Model for Gas Fueled Spark Ignition Engine Applications,” SAE Paper No. 1999-01-3482, 1999.
11.  Tabaczynski, R. J., Trinker, F. H., and Shannon B. A. S., “Further Refinement and Validation of a Turbulent Flame Propagation Model for Spark-Ignition Engines,” Combustion and Flame, 39, pp. 111-121, 1980.
12.  Blumberg, P. N., Lavoie, G. A., and Tabaczynski, R. J., “Phenomenological Models For Reciprocating Internal Combustion Engines,” Progress in Energy and Combustion Sciences, 5, pp. 123-167, 1979.
13.  Blizard, N. C., and Keck J. C., “Experimental and Theoretical Investigation of Turbulent Burning Model for Internal Combustion Engines,” SAE Paper No. 740191, 1974.
14.  Liao, S. Y., Jiang, D. M., Huang, Z. H., Cheng, Q., Gao, J., and Hu, Y., “Approximation of Flammability Region for Natural Gas-Air-Diluent Mixture,” Journal of Hazardous Materials, A125, pp. 23-28, 2005.
15.  Chin, Y. W., Mattews, R. D., Nicholas, S. P., and Kiehne, T. M., “Use of Fractal Geometry to Model Turbulent Combustion in SI Engines,” Combustion Science and Technology, 86, pp. 1-30, 1992.
16.  Abd-Alla, G. H., “Using Exhaust Recirculation in Internal Combustion Engines: a Review,” Energy Conversion and Management, 43, pp. 1027-1042, 2002.
17.  Woschni, G., “A Universally Applicable Equation for the Instantaneous Heat Transfer Coefficient in the Internal Combustion Engine,” SAE Paper No. 670931, 1967.
18.  Karim, G. A., and Zhaoda, Y., “An Analytical Model for Knock in Dual Fuel Engine of the Compression Ignition Type,” SAE Paper No. 880151, 1988.