Experimental and numerical investigation of fuel mixing effects on soot structures in counterflow diffusion flames
- 265 Downloads
Experimental and numerical analyses of laminar diffusion flames were performed to identify the effect of fuel mixing on soot formation in a counterflow burner. In this experiment, the volume fraction, number density, and particle size of soot were investigated using light extinction/scattering systems. The experimental results showed that the synergistic effect of an ethylene-propane flame is appreciable. Numerical simulations showed that the benzene (C6H6) concentration in mixture flames was higher than in ethylene-base flames because of the increase in the concentration of propargyl radicals. Methyl radicals were found to play an important role in the formation of propargyl, and the recombination of propargyl with benzene was found to lead to an increase in the number density for cases exhibiting synergistic effects. These results imply that methyl radicals play an important role in soot formation, particularly with regard to the number density.
Key WordsSoot Counterflow Light extinction/scattering Synergistic effects Number density
- Bohren, C. F. and Huffman, D. R. (1983). Absorption and Scattering of Light by Small Particles. John Willey & Sons. New York.Google Scholar
- Dobbins, R. A., Santoro, R. J. and Semerjian, H. G. (1984). Interpretation of optical measurement of soot in flames. Prog. Astronaut. Aeronaut., 92, 208–237.Google Scholar
- Dobbins, R. A., Santoro, R. J. and Semerjian, H. G. (1990). Analysis of light scattering form soot using optical cross sections for aggregates. Proc. Combust. Inst., 23, 1525.Google Scholar
- Frenlach, M. (1988). On the driving force of PAH production. Proc. Combust. Inst., 22, 1075.Google Scholar
- Glassman, I. (1988). Soot formation in combustion processes. Proc. Combust. Inst., 22, 295.Google Scholar
- Hwang, J. Y. (1999). Soot Formation in Counterflow Diffusion Flames of Ethylene and Propane. Ph. D. Dissertation. Seoul National University. Korea.Google Scholar
- Kee, R. J., Warnatz, J. and Miller, J. A. (1983). Sandia National Laboratories Report No. SAND 83-8209.Google Scholar
- Kee, R. J., Rupley, F. M., Meeks, E. and Miller, J. A. (1996). Sandia National Laboratories Report No. SAND96-8216.Google Scholar
- Solomons, T. W. G. and Fryhle, C. B. (2000). Organic Chemistry. 7th Edn. John Wiley & Sons. New York.Google Scholar
- Waldmann, L. and Schmitt, K. H. (1996). Thermophoresis and Diffusionphoresis of Aerosols. Aerosol Science (Davies, C. N. Edn). Academic Press. New York. 137–162.Google Scholar
- Wang, H., You, X., Joshi, A. V., Davis, S. G., Egolfopoulos, F. and Law, C. K. (2007). USC Mech Version II. High-Temperature Combustion Reaction Model of H2/CO/C1-C4 Compounds. http://ignis.usc.edu/USC_Mech_II.htm.