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Helieum-dilution Effect of Coflow Air on Self-excitation in Laminar Coflow Jet Flames  

Lee, Won June (부경대학교 기계공학과)
Park, Jeong (부경대학교 기계공학과)
Kwon, Oh Boong (부경대학교 기계공학과)
Baek, Se Hyun (한국전력연구원 수화력발전팀)
Ko, Sung Ho (충남대학교 기계공학과)
Publication Information
Journal of the Korean Society of Combustion / v.17, no.4, 2012 , pp. 51-59 More about this Journal
Abstract
Experimental study in coflow jet flames has been conducted to investigate the helium-dilution effect of coflow air on self-excitation. For various helium mole fractions and jet velocities, two types of self-excitation were observed: buoyancy-driven self-excitation and Lewis-number-induced self-excitation(here after called Le-ISE) coupled with buoyancy-driven one. The difference between buoyancy-driven and Le-ISE is clarified by using the Mie-scattering visualization as well as exploring the different features. The mechanism of Le-ISE is proposed. When the system Damk$\ddot{o}$hler number was lowered, Le-ISE is shown to be launched. Le-ISE is closely related to heat loss, in that it can be launched in even methane jet flame (Lewis number less than unity) with helium-diluted coflow air. Particularly, Le-ISE becomes significant as the Damk$\ddot{o}$hler number decreases and heat-loss becomes significant.
Keywords
Buoyancy; Damk$\ddot{o}$hler number; Flame length; Heat-loss; Lewis number;
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1 M. Furi, O. Papas, P. A. Monkewitz, "Non-premixed jet flame pulsations near extinction", Proc. Combust. Inst. Vol. 28, 2000, pp. 831-838   DOI   ScienceOn
2 S. H. Yoon, J. K. Han, J. Park, J. H. Yun, S. I. Keel., "Self-excitation in laminar lifted flames diluted with nitrogen", Combust. flame, Vol. 158, 2011, pp. 1960-1969   DOI   ScienceOn
3 S. H. Yoon, J. Park, O. B. Kwon, J. H. Yun, S. I. Keel, J. S. Kim, D. S. Bae, "Experimental study on self-excitations in nitrogen-diluted laminar lifted butane flames" Fuel, Vol. 91, 2012, pp. 51-60   DOI   ScienceOn
4 Kurdyumov, V. and Matalon, M., "Stabilization and onset of oscillation of an edge-flame in the nearwake of a fuel injector", Proc. Comb. Inst. Vol. 31, 909-917(2007).   DOI   ScienceOn
5 Kurdyumov, V. and Matalon, M., "Dynamics of an edge flame in a mixing layer", Comb. Flame. Vol. 139, 329-339(2004).   DOI   ScienceOn
6 Kurdyumov, V. and Matalon, M., "Radiation losses as a driving mechanism for flame oscillations", Proc. Comb. Inst. Vol. 29, 45-52(2002).   DOI   ScienceOn
7 Tran Manh Vu, Jeong Park, Oh Boong Kwon, Dae Seok Bae, Jin Han Yun, Sang In Keel, "Effects of diluents on cellular instabilities in outwardly propagating spherical syngas-air premixed flames", International Journal of Hydrogen Energy, Vol. 35, 2010, pp. 3868-3880   DOI   ScienceOn
8 J. Lee, S.H. Won, S.H. Jin, S.H. Chung, "Lifted flames in laminar jets of propane in coflow air", Combust. flame, Vol. 135, 2003, pp. 449-462   DOI   ScienceOn
9 Y.S Ko, S.H Chung, "Propagation of unsteady tribrachial flames in laminar non-premixed jets", Combust. flame, Vol. 118, 1999, pp. 151-163   DOI   ScienceOn
10 Chung, S. H. and Lee, B. J., "On the Characteristics of Laminar Lifted Flames in a Nonpremixed Jet", Combust. flame, Vol. 86 , 1991, pp. 62-72   DOI   ScienceOn
11 Lee, B. J. and Chung, S. H., "Stabilization of Lifted Tribrachial Flames in a Laminar Nonpremixed Jet", Combust. Flame, Vol. 109, 1997, pp. 163-182   DOI   ScienceOn
12 Chen, Y. C. and Bilger, R. W., "Stabilization Mechanisms of Lifted Laminar Flames in Axisymmetric Jet Flows", Combust. Flame, Vol. 122, 2000, pp. 377-399.   DOI   ScienceOn
13 Won, S. H., Chung, S. H., Cha, M. S. and Lee, B. J., "Lifted Flame Stabilization in Developing and Developed Regions of Coflow Jets for Highly Diluted Propane", Proc. Combust. Inst., Vol. 28, 2000, pp. 2093-2099.   DOI   ScienceOn
14 Won, S. H., Kim, J., Shin, M. K., Chung, S. H., Fujita, O., Mori, T., Choi, J. H. and Ito, K., 2002, "Normal and Microgravity Experiment of Oscillating Lifted Flames on Coflow", Proc. Combust. Inst., Vol. 29, pp. 37-44.   DOI   ScienceOn