Journal of the Korean Society of Propulsion Engineers (한국추진공학회지)

The Korean Society of Propulsion Engineers (한국추진공학회)
권호 표지
DOI QR코드

DOI QR Code

Numerical Investigation of the Combustion Instability inside a Partially Premixed Combustor according to Fuel Composition

연료 조성에 따른 부분예혼합 연소기 내부 연소불안정 해석

  • Nam, Jaehyun (Department of Aerospace Engineering, Seoul National University) ;
  • Yoh, Jai-ick (Department of Aerospace Engineering, Seoul National University)
  • Received : 2020.12.28
  • Accepted : 2021.03.12
  • Published : 2021.04.30
Download PDF
⟨ Previous Next ⟩

Abstract

Numerical study is conducted to analyze combustion instability in the partially premixed combustor. The simulations are performed according to fuel conditions, and Large Eddy Simulation(LES) model and PaSR combustion model are implemented in the solver. Comparison with the experimental result is conducted to confirm the validity of simulation, and quantitative and qualitative agreement is confirmed. The flame characteristics in the combustor are subsequently investigated, and the association with the occurrence of combustion instability is clarified. According to the simulation results, the flame length varies greatly depending on the fuel conditions. When the flame length becomes sufficiently long, flame-vortex interactions occurred around the wall sections, which works as the main cause of combustion instability.

부분예혼합 연소기 내 연소불안정 분석을 위한 수치적 연구가 수행되었다. 해석은 연료 조건에 따라 수행되었으며 대와류모사(Large eddy simulation, LES) 기법 및 PaSR 연소 모델이 솔버 내에 도입되었다. 수치해석의 타당성을 확인하기 위한 실험과의 비교 검증이 완료되었으며 정량적, 정성적인 일치도가 확인되었다. 연료 조건에 따라 변화하는 연소기 내 화염 특성이 이어서 조사되었으며 연소불안정 발생과의 연관성이 조사되었다. 해석 결과에 따르면 연료 조건에 따라 화염 길이가 크게 변화하였다. 그리고 화염 길이가 충분히 길어질 경우 화염-와류 상호작용이 벽면 주변에서 발생하였으며 이는 연소불안정 발생의 주요 원인이 되었음이 확인되었다.

Keywords

Acknowledgement

본 연구는 서울대학교 정밀기계연구소와 연계된 중소기업기술정보진흥청의 지원을 받아 수행한 중소기업기술혁신개발사업(82839656)의 연구결과입니다.

References

  1. Luque, S., Kanjirakkad, V., Aslanidou, I., Lubbock, R., Rosic, B., and Uchida, S., "A New Experimental Facility to Investigate Combustor-turbine Interactions in Gas Turbines with Multiple Can Combustors," Journal of Engineering for Gas Turbines and Power, Vol. 137, 051503, 2015. https://doi.org/10.1115/1.4028714
  2. Ghirardo, G., Juniper, M.P., and Moeck, J.P., "Weakly Nonlinear Analysis of Thermoacoustic Instabilities in Annular Combustors," Journal of Fluid Mechanics, Vol. 805, pp. 52-87, 2016. https://doi.org/10.1017/jfm.2016.494
  3. Franzelli, B., Riber, E., Gicquel, L.Y.M., and Poinsot, T., "Large Eddy Simulation of Combustion Instabilities in a Lean Partially Premixed Swirled Flame," Combustion and Flame, Vol. 159, No. 2, pp. 621-637, 2012. https://doi.org/10.1016/j.combustflame.2011.08.004
  4. Han, X., Li, J., and Morgans, A.S., "Prediction of Combustion Instability Limit Cycle Oscillations by Combining Flame Describing Function Simulation with a Thermoacoustic Network Model," Combustion and Flame, Vol. 162, No. 10, pp. 3632-3647, 2015. https://doi.org/10.1016/j.combustflame.2015.06.020
  5. Zettervall, Z., Worth, N.A., Mazur, M., Dawson, J.R., and Fureby, C., "Large Eddy Simulation of CH4-air and C2H4-air combustion in a model annular gas turbine combustor," Proceedings of the Combustion Institute, Vol. 37, No. 4, pp. 5223-5231, 2019. https://doi.org/10.1016/j.proci.2018.06.021
  6. Kim, M.K., Yoon, J., Oh, J., Lee, J., Yoon, Y., "An experimental study of fuel-air mixing section on unstable combustion in a dump combustor," Applied Thermal Engineering, Vol. 62, pp. 662-670, 2014. https://doi.org/10.1016/j.applthermaleng.2013.09.030
  7. Yoon, J., Lee, M.C., Joo, S., Kim, J., Yoon, Y., "Instability mode and flame structure analysis of various fuel compositions in a model gas turbine combustor," Journal of Mechanical Science and Technology, Vol. 29, No. 3, pp. 899-907, 2015. https://doi.org/10.1007/s12206-015-0203-1
  8. Taamallah, S., Vogiatzaki, K., Alzahrani, F.M., Mokheimer, E.M.A., Habib, M.A., and Ghoniem, A.F., "Fuel flexibility, stability and emissions in premixed hydrogen-rich gas turbine combustion: Technology, fundamentals, and numerical simulations," Applied Energy, Vol. 154, pp. 1020-1047, 2015. https://doi.org/10.1016/j.apenergy.2015.04.044
  9. Nicoud, F. and Ducros, F., "Subgrid-scale stress modelling based on the square of the velocity gradient tensor," Flow, Turbulence and Combustion, Vol. 62, pp. 182-200, 1999.
  10. Chomiak, J. and Karlsson, A., "Flame liftoff in diesel sprays," Proceedings of the Combustion Institute, Vol. 26, No. 2, pp. 2557-2564, 1996. https://doi.org/10.1016/S0082-0784(96)80088-9
  11. Egolfopoulos, F.N., Cho, P., and Law, C.K., "Laminar flame speeds of methane-air mixtures under reduced and elevated pressures," Combustion and Flame, Vol. 26, No. 3, pp. 2557-2564, 1996.
  12. Weller, H.G., Taber, G., Jasak, H., Fureby, C., "A tensorial approach to computational continuum mechanics using object-oriented techniques," Computers in Physics, Vol. 12, No. 6, pp. 620-631, 1998. https://doi.org/10.1063/1.168744
  13. Ribes, A., Caremoli, C., "Salome platform component model for numerical simulation," COMPSAC 07: Proceeding of the 31st Annual International Computer Software and Applications Conference, pp. 553-564, 2007.