Liftoff and blowoff of a diffusion flame between parallel streams of fuel and air
作者： Eduardo Fernández-Tarrazo , Marcos Vera , Amable Liñán
DOI: 10.1016/J.COMBUSTFLAME.2005.07.012
关键词:
摘要: A numerical analysis is presented to describe the liftoff and blowoff of a diffusion flame in mixing layer between two parallel streams fuel (mainly methane diluted with nitrogen) air emerging from porous walls. The analysis, which takes into account effects thermal expansion, assumes one-step overall Arrhenius reaction, where activation energy E allowed vary reproduce variations planar propagation velocity equivalence ratio. First, we steady flame-front structure when stabilized close wall (attached regime). Then, analyze case front located far away wall, at distance xf′ such that, upstream front, has self-similar (lifted For lifted flames, results, given here are injected same velocity, relate Uf′/SL, (relative flow) measured stoichiometric Damkohler number Dm=(δm/δL)2, based on thickness, δm, nonreacting position laminar δL. large values Dm, for wide range dilutions stream, provide that good agreement previous experimental yielding well-defined conditions blowoff. calculated can also be used transient dynamics after ignition by an external source.
elsevier.com
core.ac.uk 
sci-hub.se 参考文章(49)
Combustion in high-speed flows Kluwer Academic. ,(1994) , 10.1007/978-94-011-1050-1
Reduced Kinetic Mechanisms and Asymptotic Approximations for Methane-Air Flames: A Topical Volume Reduced Kinetic Mechanisms and Asymptotic Approximations for Methane-Air Flames. ,vol. 384, ,(1991) , 10.1007/BFB0035362
C. F. Curtiss, J. O. Hirschfelder, R. B. Bird, Molecular theory of gases and liquids ,(1954)
J Daou, A Liñán, The role of unequal diffusivities in ignition and extinction fronts in strained mixing layers Combustion Theory and Modelling. ,vol. 2, pp. 449- 477 ,(1998) , 10.1088/1364-7830/2/4/007
B.J. Lee, S.H. Chung, Stabilization of lifted tribrachial flames in a laminar nonpremixed jet Combustion and Flame. ,vol. 109, pp. 163- 172 ,(1997) , 10.1016/S0010-2180(96)00145-9
Y.S Ko, S.H Chung, Propagation of unsteady tribrachial flames in laminar non-premixed jets Combustion and Flame. ,vol. 118, pp. 151- 163 ,(1999) , 10.1016/S0010-2180(98)00154-0
Fumiaki Takahashi, Viswanath R. Katta, A reaction kernel hypothesis for the stability limit of methane jet diffusion flames Proceedings of the Combustion Institute. ,vol. 28, pp. 2071- 2078 ,(2000) , 10.1016/S0082-0784(00)80615-3
N. Peters, Laminar flamelet concepts in turbulent combustion Symposium (International) on Combustion. ,vol. 21, pp. 1231- 1250 ,(1988) , 10.1016/S0082-0784(88)80355-2
L. Muñiz, M.G. Mungal, Instantaneous flame-stabilization velocities in lifted-jet diffusion flames Combustion and Flame. ,vol. 111, pp. 16- 31 ,(1997) , 10.1016/S0010-2180(97)00096-5
Riccardo Azzoni, Stefano Ratti, Suresh K. Aggarwal, Ishwar K. Puri, The structure of triple flames stabilized on a slot burner Combustion and Flame. ,vol. 119, pp. 23- 40 ,(1999) , 10.1016/S0010-2180(99)00047-4