Investigation of Auto-Ignition of Heptane-CNG Mixture in HCCI Engine

Abstract:

Homogeneous Charge Compression Ignition (HCCI) operating principals have been widely investigated yet the uncontrollable combustion of HCCI is the major obstacle in its development. This paper is trying to increase the understanding on the auto-ignition and combustion process of several fuels to be applied in HCCI combustion system. This paper investigates variation of fuel composition between heptane and compressed natural gas (CNG) with the composition ranges from 10-100% heptane/CNG. The investigation was done in a constant volume chamber with elevated temperature (800°C). Three lambdas were tested for each fuel, namely 0.8, 1, 1.2 and 2. From the results, it is found that the mixture composition highly affects the output of the combustion of dual fuel where CNG is able to suppress heptane combustion at CNG percentage more than 40%. Furthermore, homogeneity level highly determines the types of combustion produced by the mixture, distributed or propagation flame.

• Periodical: Applied Mechanics and Materials (Volume 695)
• Pages: 468-472
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.695.468
• Online since: November 2014
• Authors: Firmansyah Firmansyah*, A. Rashid A. Aziz
• Keywords: Autoignition, CNG, Dual Fuel, Heptane

References

[1] Onishi. S., Jo. S.H., Shoda. K., Jo. P.D., Kato. S. Active thermo-atmosphere combustion (ATAC) – a new combustion process for internal combustion engines. SAE paper No. 790501. (1979).

DOI: 10.4271/790501

[2] Noguchi. M., Tanaka. Y., Takeuchi. Y. A Study on gasoline engine combustion by observatio of intermiediated reactive product during combustion. SAE paper No. 790840. (1979).

DOI: 10.4271/790840

[3] Herold. R.E., Krasselt. J.M., Foster. D.E., Ghandhi. J.B., Reuss D.L., Najt. P. M, Investigation into the effects of thermal and compositional stratification on HCCI combustion- part II: optical engine results. SAE 2009-01-1106.

DOI: 10.4271/2009-01-1105

[4] Yao. M., Zheng. Z, A numerical investigation on effects if charge stratification on HCCI combustion. SAE 2007-01-4132.

[5] Berntsson. A.W., Denbratt. I. G, HCCI combustion using charge combustion control. SAE 2007-01-0210.

DOI: 10.4271/2007-01-0210

[6] Kwon. O.S., Jeong. D.W., Lim. O.T., Lida. N, The research about thermal stratification effect on pressure rise rate in supercharged HCCI engine based on numerical analysis. SAE 2009-32-0141/20097141.

[7] Yang, Y., et al. Partial Fuel Stratification to Control HCCI Heat Release Rates: Fuel Composition and Other Factors Affecting Pre-Ignition Reactions of Two-Stage Ignition Fuels. in SAE 2011 World Congress. 2011. Detroit, Michigan, USA: SAE International.

DOI: 10.4271/2011-01-1359

[8] Ranzi, E., Gaffuri, P., Faravelli, T. A Wide Range Modeling Study of n-Heptane Oxidation. Combustion and Flame 103. 1995. Pp: 91-106.

DOI: 10.1016/0010-2180(95)00091-j

[9] Curran. H. J., Gaffuri. P., Pitz. W. J., Westbrook. C. K. A Comprehensice Modeling Study of n-Heptane Oxidation. Combustion and Flame 114. 1998. Pp: 149-177.

DOI: 10.1016/s0010-2180(97)00282-4

[10] Davidson. D.F., Gauthier B.M., Hanson. H.K. Shock tube ignition measurements of iso-octane/air and toluene/air at high pressures. Proceeding of the Combustion Institute 30. 2005. pp: 1175-1182.

DOI: 10.1016/j.proci.2004.08.004

[11] Jia. M., Xie. M. A Chemical Kinetics Model of Iso-Octane oxidation for HCCI engines. Fuel 85. 2006. pp: 2593-2604.

DOI: 10.1016/j.fuel.2006.02.018