Comptes Rendus
Ignition time of hydrogen–air diffusion flames
Comptes Rendus. Mécanique, Out of Equilibrium Dynamics, Volume 340 (2012) no. 11-12, pp. 882-893.

The ignition time of hydrogen–air diffusion flames is a quantity of utmost interest in a large number of applications, with implications regarding the viability of supersonic combustion and the safe operation of gas turbines. The underlying chemistry and the associated ignition history are very different depending on the initial temperature and pressure. This article addresses conditions that place the system above the so-called second explosion limit, as is typically the case in SCRAMJET operation, so that a branched-chain explosion characterizes the ignition process. The roles of local radical accumulation, molecular transport, and chemical reaction in nonpremixed ignition are clarified by considering the temporal evolution of an unstrained mixing layer formed between two semi-infinite spaces of hydrogen and air. The problem is formulated in terms of a radical-pool mass fraction, whose evolution in time is studied with a WKB expansion that exploits the disparity of chemical time scales present in the problem, leading to an explicit expression for the ignition time. The applicability of the analytical results for obtaining predictions of ignition distances in supersonic-combustion applications is also considered.

Published online:
DOI: 10.1016/j.crme.2012.10.035
Keywords: Hydrogen ignition, Supersonic combustion, SCRAMJETS

Antonio L. Sánchez 1, 2; Eduardo Fernández-Tarrazo 2; Pierre Boivin 2; Amable Liñán 3; Forman A. Williams 1

1 Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA 92093-0411, USA
2 Grupo de Mecánica de Fluidos, Universidad Carlos III de Madrid, 28911 Leganés, Spain
3 ETSI Aeronáuticos, Universidad Politécnica de Madrid, 28040 Madrid, Spain
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     title = {Ignition time of hydrogen{\textendash}air diffusion flames},
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Antonio L. Sánchez; Eduardo Fernández-Tarrazo; Pierre Boivin; Amable Liñán; Forman A. Williams. Ignition time of hydrogen–air diffusion flames. Comptes Rendus. Mécanique, Out of Equilibrium Dynamics, Volume 340 (2012) no. 11-12, pp. 882-893. doi : 10.1016/j.crme.2012.10.035. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/j.crme.2012.10.035/

[1] F.A. Williams Combustion Theory, Benjamin Cummings, Menlo Park, CA, 1985

[2] A. Liñán Ignition and flame spread in laminar mixing layers (J. Buckmaster; T.L. Jackson; A. Kumar, eds.), Combustion in High-Speed Flows, Kluwer Academic Publ., 1994, pp. 461-476

[3] T. Niioka Ignition time in the stretched flow field, Proc. Combust. Inst., Volume 18 (1981), pp. 1807-1813

[4] E. Mastorakos Ignition of turbulent non-premixed flames, Progr. Energy Combust. Sci., Volume 35 (2009), pp. 57-97

[5] A. Liñán; A. Crespo An asymptotic analysis of unsteady diffusion flames for large activation energies, Combust. Sci. Technol., Volume 14 (1976), pp. 95-117

[6] B. Lewis; G. Von Elbe Combustion, Flames and Explosions in Gases, Pergamon Press, New York, 1951

[7] P. Boivin; A.L. Sánchez; F.A. Williams Explicit analytic prediction for hydrogen–oxygen ignition times at temperatures below crossover, Combust. Flame, Volume 159 (2012), pp. 748-752

[8] P. Boivin; A. Dauptain; C. Jimenez; B. Cuenot Simulation of a supersonic hydrogen–air autoignition-stabilized flame using reduced chemistry, Combust. Flame, Volume 159 (2012), pp. 1779-1790

[9] P. Boivin, Reduced-kinetic mechanisms for hydrogen and syngas combustion including autoignition, PhD thesis, Universidad Carlos III de Madrid, 2011.

[10] T.S. Cheng; J.A. Wehrmeyer; R.W. Pitz; O. Jarret; G.B. Northam Raman measurement of mixing and finite-rate chemistry in a supersonic hydrogen–air diffusion flame, Combust. Flame, Volume 99 (1994), pp. 157-173

[11] A.L. Sánchez; A. Liñán; F.A. Williams A WKB analysis of radical growth in the hydrogen–air mixing layer, J. Engrg. Math., Volume 31 (1997), pp. 119-130

[12] A.L. Sánchez; A. Liñán; F.A. Williams Chain-branching explosions in mixing layers, SIAM J. Appl. Math., Volume 59 (1999), pp. 1335-1355

[13] J.D. Mellado; A.L. Sánchez; J.S. Kim; A. Liñán Branched-chain ignition in strained mixing layers, Combust. Theory Model., Volume 4 (2000), pp. 265-288

[14] P. Saxena; F.A. Williams Testing a small detailed chemical-kinetic mechanism for the combustion of hydrogen and carbon monoxide, Combust. Flame, Volume 145 (2006), pp. 316-323 http://maemail.ucsd.edu/combustion/cermech (also available at)

[15] G. del Álamo; F.A. Williams; A.L. Sánchez Hydrogen–oxygen induction times above crossover temperatures, Combust. Sci. Technol., Volume 176 (2004), pp. 1599-1626

[16] D. Fernández-Galisteo; A.L. Sánchez; A. Liñán; F.A. Williams One-step reduced kinetics for lean hydrogen–air deflagration, Combust. Flame, Volume 156 (2009), pp. 985-996

[17] D. Fernández-Galisteo; A.L. Sánchez; A. Liñán; F.A. Williams The hydrogen–air burning rate near the lean flammability limit, Combust. Theory Model., Volume 13 (2009), pp. 741-761

[18] F. Mauss; N. Peters; B. Rogg; F.A. Williams Reduced kinetic mechanisms for premixed hydrogen flames (N. Peters; B. Rogg, eds.), Reduced Kinetic Mechanisms for Applications in Combustion Systems, Springer-Verlag, Heidelberg, 1993, pp. 29-43

[19] P. Boivin; C. Jiménez; A.L. Sánchez; F.A. Williams An explicit reduced mechanism for H2–air combustion, Proc. Combust. Inst., Volume 33 (2011), pp. 517-523

[20] D.E. Rosner Transport Processes in Chemically Reacting Flows, Dover, 2000

[21] A.L. Sánchez; M. Vera; A. Liñán Exact solutions for transient mixing of two gases of different density, Phys. Fluids, Volume 18 (2006), p. 078102

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