Cetane number vs. structure in paraffin hydrocarbons

Abstract

By using a ‘reduced kinetic model’ for the spontaneous ignition of hydrocarbon–air mixtures, it is found that for n-paraffins in the diesel-fuel boiling range, there is a simple correlation between the ignition delay and the ratio of primary to secondary hydrogen atoms in the molecule. The reduced kinetic model also accounts successfully for the variation in ignition delay with chain-branching in isoparaffins, and for the acceleration of ignition in the presence of simple OH-radical sources.

References

1. J. F. Griffiths, Prog. Energy Combust. Sci., 1995, 21, 25.
2. J. F. Griffiths, K. J. Hughes, M. Schreiber and C. Poppe, Combust. Flame, 1994, 99, 533.
3. S. M. Heck, PhD Thesis, York University, Toronto 1998.
4. P. Q. E. Clothier, B. D. Aguda, A. Moise and H. O. Pritchard, Chem. Soc. Rev., 1993, 22, 101.
5. A. Cox, J. F. Griffiths, C. Mohamed, H. J. Curran, W. J. Pitz and C. K. Westbrook, 26th Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, 1996, p. 2685.
6. R. H. Barbour, Esso Research Centre, Abingdon, personal communication.
7. A. D. Puckett and B. H. Caudle, Ignition Qualities of Hydrocarbons in the Diesel-fuel Boiling Range, United States Department of the Interior, Bureau of Mines, 1948, I.C. 7474.
8. B. Lewis and G. von Elbe, Combustion, Flames and Explosions of Gases, Academic Press, New York, 2nd edn., 1961, p. 146.
9. S. W. Benson, J. Chem. Phys., 1964, 40, 1007.
10. G. Williams and A. S. C. Lawrence, Proc. R. Soc., London, Ser. A, 1936, 156, 455.
11. F. F. Fenter, B. Nozière, F. Caralp and R. Lesclaux, Int. J. Chem. Kinet., 1994, 26, 171.
12. P. Q. E. Clothier, D. Shen and H. O. Pritchard, Combust. Flame, 1995, 101, 383.
13. P. Q. E. Clothier, A. Moise and H. O. Pritchard, Combust. Flame, 1990, 81, 242.