Abstract
In an earlier study, the current authors showed that an unsteady-state lifted flame generated by an equivalence ratio conversion system for a given fuel, was similar to a steady-state lifted flame in terms of the change characteristics from a premixed flame to a critical flame and then to a triple flame with a diffusion flame positioned in the middle according to the concentration difference. Therefore, this study used an OH-PLIF method to investigate the characteristics of a steady-state lifted flame and an unsteady-state lifted flame created under conditions identical to the flames in the preceding study. PLIF (Planar laser induced fluorescence) is practically effective for visualizing the concentration fields within a flame. The resulting OH-radical measurements showed that an unsteady-state lifted flame created under the specific conditions used in this study showed similar tendencies in terms of OH-radical distribution, fluorescence intensity, and liftoff height, to a steady-state lifted flame, thereby confirming that the behavior of an unsteady-state lifted flame can be effectively predicted based on the behavior of a steady-state lifted flame.
Similar content being viewed by others
References
Azzoni, R., Ratti, S., Aggarwal, S. K. and Puri, I. K. (1999). The structure of triple flame stabilized on a slot burner. Combustion and Flame, 119, 23–40.
Dold, J. W. (1989). Flame propagation in a nonuniform mixture: Analysis of a slowly varying triple flame. Combustion and Flame, 76, 71–88.
Jang, J. Y., Kim, T. K. and Park, J. (2005). A transitional behavior of a premixed flame and a triple flame in a lifted flame (I). Trans. Korean Society Mechanical Engineer (B) 29, 3, 368–375.
Jun, S. H., Kidoguchi, Y., Kim, T. K. and Miwa, K. (2008). Characteristics of lifted flame resulting from impulsive change of equivalence ratio. J. Combustion Society of Japan 50, 152, 145–151.
Kim, N. I., Seo, J. I., Guahk, Y. T. and Shin, H. D. (2006). The propagation of tribrachial flames in a confined channel. Combustion and Flame, 144, 168–179.
Kim, T. K. and Jang, J. Y. (2005). A transitional behavior of a premixed flame and a triple flame in a lifted flame (II). Trans. Korean Society Mechanical Engineer (B) 29, 3, 376–383.
Kioni, P. N., Bray, K. N. C., Greenhalgh, D. A. and Rogg, B. (1999). Experimental and numerical studies of a triple flame. Combustion and Flame, 116, 192–206.
Kioni, P. N., Rogg, B., Bray, K. N. C. and Liñán, A. (1993). Flame spread in laminar mixing Layers: The triple flame. Combustion and Flame, 95, 276–290.
Lee, J. K. and Nishido, K. (2008). Development of an LIF processing technique for measuring drop sizes in a pre-swirl spray. Int. J. Automotive Technology 9, 4, 381–390.
Lee, W. N. and Seo, D. G. (2005). A study on the stability of rich/lean methane premixed flame. Trans. Korean Society of Automotive Engineers 13, 2, 225–233.
Morel, T. (1975). Comprehensive design of axisymmetric wind tunnel contractions. ASME J. Fluids Eng., 225–233.
Muńiz, L. and Mungal, M. G. (1997). Instantaneous flame-stabilization velocities in lifted-jet diffusion flames. Combustion and Flame, 111, 16–31.
Park, J. K., Lee, S. Y. and Santoro, R. (2002). Laserinduced soot vaporization characteristics in the laminar diffusion flames. Trans. Korean Society of Automotive Engineers 3, 3, 95–99.
Plessing, T., Terhoeven, P., Peter, N. and Mansour, M. S. (1998). Experimental and numerical study of a laminar triple flame. Combustion and Flame, 115, 335–353.
Schefer, R. W. and Goix, P. J. (1998). Mechanism of flame stabilization in turbulent lifted-jet flames. Combustion and Flame, 112, 559–574.
Schefer, R. W., Namazian, M. and Kelly, J. (1994). Stabilization of lifted turbulent-jet flames. Combustion and Flame, 99, 75–86.
Watson, K. A., Lyons, K. M., Donbar, J. M. and Carter, C. D. (1999). Scalar and velocity field measurements in a lifted CH4-Air diffusion flame. Combustion and Flame, 117, 257–271.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Jun, S.H., Kim, T.K., Jang, J.Y. et al. OH-radical behavior of unsteady lifted flame based on instantaneous change of the equivalence ratio. Int.J Automot. Technol. 10, 663–668 (2009). https://doi.org/10.1007/s12239-009-0078-1
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12239-009-0078-1