Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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A Numerical Study on Nonlinear Dynamic Behavior of Diffusive-Thermal Instability in Diluted CH4/O2 Conterflow Diffusion Flames

희석된 메탄/산소 대향류 확산화염에서 확산-열 불안정으로 인한 화염의 비선형 동적 거동에 관한 수치해석

  • 손채훈 (조선대학교 항공우주공학과)
  • Published : 2004.06.01
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Abstract

Nonlinear dynamic behavior of diffusive-thermal instability in diluted CH$_4$/O$_2$ diffusion flames is numerically investigated by adopting detailed chemistry and transport. Counterflow diffusion flame is adopted as a model flamelet. Particular attention is focused on the pulsating-instability regime, which arises for Lewis numbers greater than unity, and the instability occurs at high strain rate near extinction condition in this flame configuration. Once a steady flame structure is obtained for a prescribed value of initial strain rate, transient solution of the flame is calculated after a finite amount of strain-rate perturbation is imposed on the steady flame. Transient evolution of the flame depends on the initial strain rate and the amount of perturbed strain rate. Basically, the dynamic behaviors can be classified into two types, namely non-oscillatory decaying solution and diverging solution leading to extinction. The peculiar oscillatory solution, which has been found in the previous study adopting one-step chemistry and constant Lewis numbers, is net observed in this study, which is attributed to both convective flow and preferential diffusion effects.

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References

  1. Strehlow, R. A., 1985, Combustion Funda mentals, McGraw-Hill, Inc.
  2. Chen,· R., Mitchell, G. B. and Ronney, P. D., 1992, 'Diffusive-Thermal Instability and Flame Exinction in Nonpremixed Combustion,' Twenty-Fourth Symposium(International) on Combustion, The Combustion Institute, Pittsburgh, PA, pp. 213-221
  3. Kim, J. S., Williams, F. A. and Ronney, P. D., 1996, 'Diffusional-Thermal Instability of Diffusion Flames with Lewis Numbers Close to Unity,' Journal of Fluid Mechanics, Vol. 327, pp. 273-301 https://doi.org/10.1017/S0022112096008543
  4. Kim, J. S., 1997, 'Linear Analysis of Diffusional-Thermal Instability of Diffusion Flames with Lewis Numbers Close to Unity,' Combustion Theory and Modelling, Vol. 1, pp. 13-40 https://doi.org/10.1080/713665228
  5. Cheatham, S. and Matalon, M., 1996, 'Heat Loss and Lewis Number Effects on the Onset of Ossilations in Diffusion Flames,' Twenty-Sixth Symposium (International) on Combustion, The Combustion Institute, Pitttsburgh, PA, pp. 1063-1070
  6. Nayagam, V. and Williams, F. A., 1998, 'Dynamics of Diffusion Flame Oscillations Prior to Extinction During Low Gravity Droplet Combustion,' Seventh International Conference on Numerical Combustion, York, England, Mar. 30 - Apr. 1, p. 46
  7. Sohn, C. H., Chung, S. H. and Kim, J. S., 1999, 'Instability-Induced Extinction of Diffusion Flames Established in the Stagnant Mixing Layer,' Combustion and Flame, Vol. 117, pp. 404-412 https://doi.org/10.1016/S0010-2180(98)00088-1
  8. Sohn, C. H., Kim, J. S., Chung, S. H. and Maruta, K., 2000, 'Nonlinear Evolution of Diffusion Flame Oscillations Triggered by Radiative Heat Loss,' Combustion and Flame, Vol. 123, pp. 95-106 https://doi.org/10.1016/S0010-2180(00)00148-6
  9. Sohn, C. H. and Chung, S. H., 2001, 'A Numerical Study on Radiation-Induced Oscillatory Instability in $CH_4/Air$ Diffusion Flames,' Transactions of the KSME (B), Vol. 25, pp. 29-35
  10. Christiansen, E. W., Tse, S. D. and Law, C. K., 2003, 'A Computational Study of Oscillatory Extinction of Spherical Diffusion Flames,' Combustion and Flame, Vol. 134, pp. 327-337 https://doi.org/10.1016/S0010-2180(03)00112-3
  11. Kim, H. J., Chung, S. H. and Sohn, C. H., 2003, 'Nonlinear Acoustic-Pressure Responses of $H_2/Air$ Counterflow Diffusion Flames,' Transactions of the KSME (B), Vol. 27, No. 8, pp. 1158-1164 https://doi.org/10.3795/KSME-B.2003.27.8.1158
  12. Kee, R. J., Wamatz, J. and Miller, J. A., 1983, 'A Fortran Computer Code Package for the Evaluation of Gas-Phase Viscosities, Conductivities, and Diffusion Coefficients,' Sandia National Laboratories Report, SAND83-8209
  13. Kee, R. J., Grear, J. F., Smooke, M. D. and Miller, J. A., 1990, 'A Fortran Program for Modelling Steady Laminar One-Dimensional Premixed Flames,' Sandia National Laboratories Report, SAND85-8240
  14. Kee, R. J., Rupley, F. M. and Miller, J. A., 1989, 'CHEMKlN-II:A Fortran Chemical Kinetics Package for the Analysis of Gas-Phase Chemical Kinetics,' Sandia National Laboratories Report, SAND89-8009
  15. Sohn, C. H., Chung, S. H., Lee, S. R. and Kim, J. S., 1998, 'Structure and Acoustic - Pressure Response of Hydrogen-Oxygen Diffusion Flames at High Pressure,' Combustion and Flame, Vol. 115, pp. 299-312 https://doi.org/10.1016/S0010-2180(98)00007-8
  16. Sohn, C. H., Jeong, I. M. and Chung, S. H., 2002, 'Numerical Study of the Effects of Pressure and Air-Dilution on NO Formation in Laminar Counterflow Diffusion Flames of Methane in High Temperature Air,' Combustion and Flame, Vol. 130, pp. 83-93 https://doi.org/10.1016/S0010-2180(02)00366-8

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