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Direct numerical simulation of the autoignition of a hydrogen plume in a turbulent coflow of hot air

  • S. G. Kerkemeier (a1), C. N. Markides (a2), C. E. Frouzakis (a1) and K. Boulouchos (a1)

Abstract

The autoignition of an axisymmetric nitrogen-diluted hydrogen plume in a turbulent coflowing stream of high-temperature air was investigated in a laboratory-scale set-up using three-dimensional numerical simulations with detailed chemistry and transport. The plume was formed by releasing the fuel from an injector with bulk velocity equal to that of the surrounding air coflow. In the ‘random spots’ regime, autoignition appeared randomly in space and time in the form of scattered localized spots from which post-ignition flamelets propagated outwards in the presence of strong advection. Autoignition spots were found to occur at a favourable mixture fraction close to the most reactive mixture fraction calculated a priori from considerations of homogeneous mixtures based on inert mixing of the fuel and oxidizer streams. The value of the favourable mixture fraction evolved in the domain subject to the effect of the scalar dissipation rate. The hydroperoxyl radical appeared as a precursor to the build-up of the radical pool and the ensuing thermal runaway at the autoignition spots. Subsequently, flamelets propagated in all directions with complex dynamics, without anchoring or forming a continuous flame sheet. These observations, as well as the frequency of and scatter in appearance of the spots, are in good agreement with experiments in a similar set-up. In agreement with experimental observations, an increase in turbulence intensity resulted in a downstream shift of autoignition. An attempt is made to understand the key processes that control the mean axial and radial locations of the spots, and are responsible for the observed scatter. The advection of the most reactive mixture through the domain, and hence the history of evolution of the developing radical pools were considered to this effect.

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Corresponding author

Email address for correspondence: frouzakis@lav.mavt.ethz.ch

References

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del Álamo, G., Williams, F. A. & Sánchez, A. L. 2004 Hydrogen–oxygen induction times above crossover temperatures. Combust. Sci. Technol. 176 (10), 15991626.
Baritaud, T. A., Heinze, T. A. & Coz, J. F. Le. 1994 Spray and self-ignition visualization in a DI Diesel engine. SAE Paper, 940681.
Bilger, R. W., Stårner, S. H. & Kee, R. J. 1990 On reduced mechanism for methane – air combustion in nonpremixed flames. Combust. Flame 80 (2), 135149.
Blouch, J. D. & Law, C. K. 2003 Effects of turbulence on nonpremixed ignition in heated counterflow. Combust. Flame 132 (3), 512522.
Blouch, J. D., Sung, C. J., Fotache, C. G. & Law, C. K. 1998 Turbulent ignition of non-premixed hydrogen by heated counterflowing atmospheric air. Proc. Combust. Inst. 27 (1), 12211228.
Cabra, R., Chen, J.-Y., Dibble, R. W., Karpetis, A. N. & Barlow, R. S. 2005 Lifted methane–air jet flames in a vitiated coflow. Combust. Flame 143 (4), 491506.
Cabra, R., Myhrvold, T., Chen, J. Y., Dibble, R. W., Karpetis, A. N. & Barlow, R. S. 2002 Simultaneous laser Raman–Rayleigh-LIF measurements and numerical modeling results of a lifted turbulent ${\mathrm{H} }_{2} / {\mathrm{N} }_{2} $ jet flame in a vitiated coflow. Proc. Combust. Inst. 29 (2), 18811888.
Conaire, M. Ó., Curran, H. J., Simmie, J. M., Pitz, W. J. & Westbrook, C. K. 2004 A comprehensive modeling study of hydrogen oxidation. Intl J. Chem. Kinet. 36 (11), 603622.
Dally, B. B., Karpetis, A. N. & Barlow, R. S. 2002 Structure of turbulent nonpremixed jet flames in a diluted hot coflow. Proc. Combust. Inst. 29 (1), 11471154.
Deville, M. O., Fischer, P. F. & Mund, E. H. 2002 High-order Methods for Incompressible Fluid Flows. Cambridge University Press.
Echekki, T. & Chen, J. H. 2003 Direct numerical simulations of auto-ignition in non-homogeneous hydrogen–air mixtures. Combust. Flame 134 (3), 169191.
Fischer, P. F., Lottes, J. W. & Kerkemeier, S. G. 2011 nek5000 web page http://nek5000.mcs.anl.gov.
Gibson, C. H. 1968 Fine structure of scalar fields mixed by turbulence: I. Zero-gradient points and minimal gradient surfaces. Phys. Fluids 11 (11), 23052315.
Gordon, R. L., Masri, A. R. & Mastorakos, E. 2008 Simultaneous Rayleigh temperature, OH- and ${\mathrm{CH} }_{2} $ O-LIF imaging of methane jets in a vitiated coflow. Combust. Flame 155 (1–2), 181195.
Hilbert, R. & Thèvenin, D. 2002 Autoignition of turbulent non-premixed flames investigated using direct numerical simulations. Combust. Flame 128 (1–2), 2237.
Hindmarsh, A. C., Brown, P. N., Grant, K. E., Lee, S. L., Serban, R., Shumaker, D. E. & Woodward, C. S. 2005 SUNDIALS: suite of nonlinear and differential/algebraic equation solvers. ACM Trans. Math. Softw. 31 (3), 363396.
Huang, M.-J. & Leonard, A. 1994 Power-law decay of homogeneous turbulence at low Reynolds numbers. Phys. Fluids 6 (11), 37653775.
Im, H. G., Chen, J. H. & Law, C. K. 1998 Ignition of hydrogen–air mixing layer in turbulent flows. Proc. Combust. Inst. 27, 10471056.
Kerkemeier, S. G. 2010 Direct numerical simulation of combustion on petascale platforms: application to turbulent non-premixed hydrogen autoignition. PhD thesis, Swiss Federal Institute of Technology (ETH), Zurich, Switzerland.
Kim, I. S. 2004 Conditional moment closure for non-premixed turbulent combustion. PhD thesis, University of Cambridge, Cambridge, UK.
Klein, M., Sadiki, A. & Janicka, J. 2003 A digital filter based generation of inflow data for spatially developing direct numerical or large eddy simulations. J. Comput. Phys. 186 (2), 652665.
Lee, Y. Y. & Pope, S. B. 1995 Nonpremixed turbulent reacting flow near extinction. Combust. Flame 101 (4), 501528.
Lemoine, F., Antoine, Y., Wolff, M. & Lebouche, M. 2000 Some experimental investigations on the concentration variance and its dissipation rate in a grid generated turbulent flow. Intl J. Heat Mass Transfer. 43 (7), 11871199.
Li, J., Zhao, Z., Kazakov, A. & Dryer, F. L. 2004 An updated comprehensive kinetic model of hydrogen combustion. Intl J. Chem. Kinet. 36 (10), 566575.
Liñán, A. & Crespo, A. 1976 An asymptotic analysis of unsteady diffusion flames for large activation energies. Combust. Sci. Technol. 14 (1), 95117.
Lu, T. F., Yoo, C. S., Chen, J. H. & Law, C. K. 2010 Three-dimensional direct numerical simulations of a turbulent lifted hydrogen jet flame in heated coflow: a chemical explosive mode analysis. J. Fluid Mech. 652, 4564.
Markides, C. N. 2005 Autoignition in turbulent flows. PhD thesis, University of Cambridge, Cambridge, UK.
Markides, C. N. & Mastorakos, E. 2005 An experimental study of hydrogen autoignition in a turbulent co-flow of heated air. Proc. Comb. Inst. 30 (1), 883891.
Markides, C. N. & Mastorakos, E. 2006 Measurements of scalar dissipation in a turbulent plume with planar laser-induced fluorescence of acetone. Chem. Engng Sci. 61 (9), 28352842.
Markides, C. N. & Mastorakos, E. 2008a Flame propagation following the autoignition of axisymmetric hydrogen, acetylene and normal-heptane plumes in turbulent co-flows of hot air. J. Engng Gas Turbine Power 130, 011502.
Markides, C. N. & Mastorakos, E. 2008b Measurements of the statistical distribution of the scalar dissipation rate in turbulent axisymmetric plumes. Flow Turb. Combust. 81 (1–2), 221234.
Markides, C. N. & Mastorakos, E. 2011 Experimental investigation of the effects of turbulence and mixing on autoignition chemistry. Flow Turbul. Combust. 86 (3–4), 585608.
Markides, C. N., de Paola, G. & Mastorakos, E. 2007 Measurements and simulations of mixing and autoignition of an $n$ -heptane plume in a turbulent flow of heated air. Exp. Thermal Fluid Sci. 31 (5), 393401.
Mastorakos, E. 2009 Ignition of turbulent non-premixed flames. Prog. Energy Combust. Sci. 35 (1), 5797.
Mastorakos, E., Baritaud, T. A. & Poinsot, T. J. 1997a Numerical simulations of autoignition in turbulent mixing flows. Combust. Flame 109 (1–3), 198223.
Mastorakos, E., da Cruz, A. P., Baritaud, T. A. & Poinsot, T. J. 1997b A model for the effects of mixing on the autoignition of turbulent flows. Comb. Sci. Technol. 125 (1–6), 243282.
Medwell, P. R., Kalt, P. A. M. & Dally, B. B. 2007 Simultaneous imaging of $oh$ , formaldehyde, and temperature of turbulent nonpremixed jet flames in a heated and diluted coflow. Combust. Flame 148 (1–2), 4861.
Medwell, P. R., Kalt, P. A. M. & Dally, B. B. 2008 Imaging of diluted turbulent ethylene flames stabilised on a jet in hot coflow (JHC) burner. Combust. Flame 152 (1–2), 100113.
Mizutani, Y., Nakabe, K. & Chung, J. D. 1990 Effects of turbulent mixing on spray ignition. Proc. Combust. Inst. 23 (1), 14551460.
Mohamed, M. S. & LaRue, J. C. 1990 The decay power law in grid-generated turbulence. J. Fluid Mech. 219, 195214.
Moin, P. & Mahesh, K. 1998 Direct numerical simulation: a tool in turbulence research. Annu. Rev. Fluid Mech. 30, 539578.
Nakamura, I., Sakai, Y. & Miyata, M. 1987 Diffusion of matter by a non-buoyant plume in grid-generated turbulence. J. Fluid Mech. 178, 379403.
O’Brien, E. E. & Jiang, T.-L. 1991 The conditional dissipation rate of an initially binary scalar in homogeneous turbulence. Phys. Fluids A 3 (12), 31213123.
Oldenhof, E., Tummers, M. J., van Veen, E. H. & Roekaerts, D. J. E. M. 2010 Ignition kernel formation and lift-off behaviour of jet-in-hot-coflow flames. Combust. Flame 157 (6), 11671178.
Peters, N. 1983 Local quenching due to flame stretch and non-premixed turbulent combustion. Combust. Sci. Technol. 30 (1–6), 117.
Pizza, G., Frouzakis, C. E., Mantzaras, J., Tomboulides, A. G. & Boulouchos, K. 2010 Three-dimensional simulations of premixed hydrogen/air flames in microtubes. J. Fluid Mech. 658, 463491.
Pope, S. B. 2000 Turbulent Flows. Cambridge University Press.
Sreedhara, S. & Lakshmisha, K. N. 2000 Direct numerical simulation of autoignition in a nonpremixed, turbulent medium. Proc. Combust. Inst. 28 (1), 2533.
Sreedhara, S. & Lakshmisha, K. N. 2002 Assessment of conditional moment closure models for turbulent autoignition using DNS data. Proc. Combust. Inst. 29 (2), 20512059.
Sutton, O. G. 1932 A theory of eddy diffusion in the atmosphere. Proc. R. Soc. Lond. A 135 (826), 143165.
Tomboulides, A. G., Lee, J. C. Y. & Orzag, S. A. 1997 Numerical simulation of low Mach number reactive flows. J. Sci. Comput. 12, 139167.
Viggiano, A. & Magi, V. 2004 A 2-D investigation of $n$ -heptane autoignition by means of direct numerical simulation. Combust. Flame 137 (4), 432443.
Wong, C. L. & Steere, D. E. 1982 The effects of diesel fuel properties and engine operating conditions on ignition delay. SAE Paper, 821231.
Wu, Z., Masri, A. R. & Bilger, R. W. 2006 An experimental investigation of the turbulence structure of a lifted ${\mathrm{H} }_{2} / {\mathrm{N} }_{2} $ jet flame in a vitiated co-flow. Flow Turbul. Combust. 76 (1), 6181.
Yetter, R. A., Dryer, F. L. & Rabitz, H. 1991 A comprehensive reaction mechanism for carbon monoxide/hydrogen/oxygen kinetics. Combust. Sci. Technol. 79 (1–3), 97128.
Yoo, C. S., Richardson, E. S., Chen, R. & Sankaran, J. H. 2011 A DNS study on the stabilization mechanism of a turbulent lifted ethylene jet flame in highly-heated coflow. Proc. Combust. Inst. 33 (1), 16191627.
Yoo, C. S., Sankaran, R. & Chen, J. H. 2009 Three-dimensional direct numerical simulation of a turbulent lifted hydrogen jet flame in heated coflow: flame stabilization and structure. J. Fluid Mech. 640, 453481.
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Direct numerical simulation of the autoignition of a hydrogen plume in a turbulent coflow of hot air

  • S. G. Kerkemeier (a1), C. N. Markides (a2), C. E. Frouzakis (a1) and K. Boulouchos (a1)

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