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모형 가스터빈 연소기의 입구 형상변화에 따른 연소 불안정성에 관한 LES 연구

LES Studies on the Combustion Instability with Inlet Configurations in a Model Gas Turbine Combustor

  • 발행 : 2008.05.01

초록

The effects of combustion instability on flow structure and flame dynamics with the inlet configurations in a model gas turbine combustor were investigated using large eddy simulation (LES). A G-equation flamelet model was employed to simulate the unsteady flame behaviors. As a result of mean flow field, the change of divergent half angle($\alpha$) at combustor inlet results in variations in the size and shape of the central toroidal recirculation (CTRZ) as well as the flame length by changing corner recirculation zone (CRZ). The case of ${\alpha}=45^{\circ}$ show smaller size and upstream location of CTRZ than those of $90^{\circ}$ and $30^{\circ}$ by the development of higher swirl velocity. The flame length in the case of ${\alpha}=45^{\circ}$ is shorter than other cases, while the case of ${\alpha}=30^{\circ}$ yields the longest flame length due to the decrease of effective reactive area with the absence of CRZ. Through the analysis of pressure fluctuation, it was identified that the case of ${\alpha}=45^{\circ}$ shows the largest damping effect of pressure oscillation in all configurations and brings in the noise reduction of 2.97dB, compared to that of ${\alpha}=30^{\circ}$ having the largest pressure oscillation. These reasons were discussed in detail through the analysis of unsteady phenomena related to recirculation zone and flame surface. Finally the effects of flame-acoustic interaction were evaluated using local Rayleigh parameter.

키워드

참고문헌

  1. Lilley, D. G., 1977, “Swirl Flows in Combustion: a Review,” AIAA Journal, Vol. 15, No. 8, pp. 1063-1078 https://doi.org/10.2514/3.60756
  2. Kulsheimer, C. and Buchner, H., 2002, “Combustion Dynamics of Turbulent Swirling Flames,” Combustion and Flame, Vol. 131, pp. 70-84 https://doi.org/10.1016/S0010-2180(02)00394-2
  3. Sivasegaram, S. and Whitelaw, J., 1991, “The Influence of Swirl on Oscillations in Ducted Premixed Flames,” Combust. Sci. and Tech., Vol. 138, pp.195-205
  4. Rayleigh, J. W. S., 1945, “The Theory of Sound,” Vol. II, Dover Publications, New York
  5. Candel, S., 2002, “Combustion Dynamics and Control: Progress and Challenges,” Proceedings of the Combustion Institute, Vol. 29, pp. 1-28 https://doi.org/10.1016/S1540-7489(02)80007-4
  6. Syred, N., 2006, “A Review of Oscillation Mechanisms and the Role of the Processing Vortex Core(PVC) in Swirl Combustion Systems,” Progress in Energy and Combustion Science, Vol. 32, pp. 93-161 https://doi.org/10.1016/j.pecs.2005.10.002
  7. Dawson, J. R., Rodriguez-Martinez, V. M., Syred, N. and Odoherty, T., 2005, “The Effect of Combustion Instability on the Structure of Recirculation Zones in Confined Swirling Flames,” Combust. Sci. and Tech., Vol. 177, pp. 2349-2371 https://doi.org/10.1080/00102200500241149
  8. Poinsot, T. and Veynante, D., 2001, “Theoretical Numerical Combustion,” Edwards
  9. Menon, S., Yeung, P. K. and Kim, W. W., 1996,“Effect of Subgrid Models on the Computed Interscale Energy Transfer in Isotropic Turbulence,” Computers and Fluids, Vol. 25, No. 2, pp. 165-180 https://doi.org/10.1016/0045-7930(95)00036-4
  10. Kim, W. W. and Menon, S., 1995, “A New Dynamic One-equation Subgrid-scale Model for Large-eddy Simulation,” AIAA-95-0356
  11. Menon, S. and Jou, W. H., 1991, “Large-eddy Simulations of Combustion Instability in an Axi-Symmetric Ramjet Combustor," Combust. Sci. and Tech., Vol. 75, pp. 53-72 https://doi.org/10.1080/00102209108924078
  12. Lipatnikov, A. N. and Chomiak, J., 2000, “Tur- Bulent Flame Speed and Thickness : Phenomenology, Evaluation and Application in Multi-dimensional Simulations,” Progress in Energy and Combustion Science, Vol. 28, pp. 1-74 https://doi.org/10.1016/S0360-1285(01)00007-7
  13. Kee, R. J., Grcar, J. F., Smooke, M. D. and Miller, J. A., 1994, “A Fortran Program for Modeling Steady Laminar One-dimensional Premixed Flames,” SAND85-8240
  14. MacCormack, 1969, "The Effects of Viscosity in Hyper-velocity Impact Cratering," AIAA Paper 69-354
  15. Hwang, C. H. and Lee, C. E., 2006, “Performance Evaluation of Large Eddy Simulation for Recirculating and Swirling Flows,” Transactions of KSME B, Vol. 30, No. 4, pp. 364-372 https://doi.org/10.3795/KSME-B.2006.30.4.364
  16. Hwang, C. H. and Lee, C. E., 2006, “Large Eddy Simulation of Swirling Premixed Flames in a Model Gas Turbine Combustor,” J. of the Korean Soc. for Aero. & Space Sci., Vol. 34, No. 7, pp. 79-88
  17. Broda, J. C., Seo, S., Santoro, R. J., Shirhattikar, G. and Yang, V., 1998, “An Experimental Study of Combustion Dynamics of a Premixed Swirl Injector,” Proceedings of the Combustion Institute, Vol. 27, pp.1849-1856
  18. Huang, V., Sung, H. G., Heish, S. Y. and Yang, V., 2003, “Large-eddy Simulation of Combustion Dynamics of Lean-premixed Swirl-stabilized Combustor,” Journal of Propulsion and Power, Vol. 19, No. 5, pp. 782-794 https://doi.org/10.2514/2.6194
  19. Poinsot, T. J. and Lele, S. K., 1992, “Boundary Conditions for Direct Simulations of Compressible Viscous Flows,” J. Computational Physics, Vol. 101, pp. 104-129 https://doi.org/10.1016/0021-9991(92)90046-2