DOI QR코드

DOI QR Code

스월 예혼합 버너의 연소 특성 및 NO 배출에 관한 수치적 연구

Numerical Study of Combustion Characteristics and NO Emission in Swirl Premixed Burner

  • 투고 : 2013.03.25
  • 심사 : 2013.08.29
  • 발행 : 2013.10.01

초록

Double cone 버너를 장착한 가스터빈용 EV (Environmental Vortex)버너의 연소 특성과 NO 배출 특성을 수치적으로 조사하였다. NO 배출 저감을 위해 연료와 공기의 혼합 특성을 예측하였다. 혼합도와 NO 배출과의 상관관계를 예측하기 위해 메탄 1단계 화학반응식과 2단계 반응식에 적용하여 연소 해석을 수행하였다. 1단계 반응식을 적용한 결과, 혼합도가 저하된 모델에서 NO 배출량이 약 2% 증가하였으며, 혼합도가 향상된 모델의 경우 cone 상부에서 과다한 고온의 화염 영역이 형성되어 NO가 약 169%나 증가하였다. 2단계 반응식의 경우 첫 번째 모델에서 약 3% NO 배출량이 증가하였으며, 두 번째 모델에서 cone 내부의 고온 영역이 형성되지 않고 NO가 약 5% 감소하였다. 이 결과는, 혼합 특성이 저감된 모델에서 NO가 약 63% 증가하였고, 혼합 특성이 향상된 모델에서 NO가 약 11% 감소한 실험결과와 잘 부합하였다. 정량적인 오차가 있음에도, NO 배출의 정성적 경향성이 유사하므로 2단계 반응식을 적용한 수치해석을 통해 설계 변경 방안을 제시하는 것은 타당할 것으로 판단된다.

The combustion characteristics of an EV (Environmental Vortex) burner (double-cone burner) adopted in a gas turbines are numerically investigated. The mixing of fuel and air is analyzed for reduction of NO emission. To predict the correlation between NO emission and fuel-air mixedness, 1-step and 2-step chemistry models are adopted. The results calculated by 1-step chemistry showed that NO emissions increased by 2% in the case of degraded mixedness and by 169% in the case of improved mixedness, where the temperature in the flame zone was overestimated upstream of the cone. However, the corresponding results calculated by 2-step chemistry showed that NO emission increased by 3% and decreased by 5%, where the flame zone was not formed inside the cone. The latter results agree well with the experimental ones indicating an increase of 63% and decrease of 11% in the respective cases. Despite quantitative errors, NO emissions can be predicted reasonably by the application of the 2-step chemistry model adopted here and design modification of burner for NO reduction can be proposed based on the numerical data.

키워드

참고문헌

  1. Peter, F., Martin, Z., Rudolf L., Stefano, B., Christian, M., 2007, "Development and Design of Alstom's Staged Fuel Gas Injection EV Burner for NOx Reduction," ASME Turbo Expo, GT2007-27730.
  2. Yu, J. H., Kim, B. G., Chang, Y. J., 2008, "LES Modeling Study on the Characteristics of NOx Emissions in a Lean Premixed Combustor Implementing LES Model," KSME Spring conference, pp. 381-386.
  3. Capehart, S, A, John, C. Y, "Effect of Fuel Combustion on $NO_X$ Formation in Lean Premixed Prevaporized Combustion" ASME, 97-GT-336, 1997.
  4. Paschereit, C. O., Schuermans, B., Buche, D., 2003, "Combustion Process Optimization Using Eveolutionary Algorithm," ASME Turbo Expo, GT-38393.
  5. Paschereit, C. O., Flohr, F., Knopfel, H., Geng, W., Steinbach, C., Stuber, P., Bemgtsson, K., Gutmark, E., 2002, "Combustion Control by Extended EV Burner Fuel Lance," ASME Turbo Expo, GT-30462.
  6. Linan, A., Williams, F. A., 1993, "Fundamental Aspects of Combustion," Oxford University Press, pp. 9-13.
  7. ANSYS FLUENT Theory Guide V13.0, 2010, ANSYS Inc.
  8. Polike, W., Dobbeling, W., Sattelmayer, T., Nicol, D, G., 1996, "A $NO_X$ Prediction Scheme for Lean-Premixed Gas Turbine Based on Detailed Chemical Kinetics," ASME, Vol. 118, pp. 775-776.
  9. Turns, S. R., 2000, "An Introduction to Combustion," Mc-Graw Hill, pp. 472-507.
  10. Melte, P. C., Pratt, D. T., 1975 "Measurement of Atomic Oxygen and Nitrogen Oxides In Jet Stirred Combustion," Symposium on Combustion, Vol. 15, pp. 1061-1070.
  11. Fernando, B., Felic, G., 2007, "Effect of Pressure and Fuel-Air Unmixedness on $NO_X$ Emissions from Industrial Gas Turbine Burners," Combustion and Flame, Vol. 151, pp. 274-288. https://doi.org/10.1016/j.combustflame.2007.04.007
  12. Yu, M. J., 1999, "Investigation of Combustion and Nox Emission Characteristics for Pulverized Coal with Radiation Effects," PhD Dissertation, KAIST, pp. 63-65.
  13. Lim, I. G., Chung, S. H., 1995, "Numerical Study of Interacting Premixed Flames Including Gas Phase Radiation." Trans. Korean Soc. Mech. Eng. B, Vol. 19, pp 858-867.
  14. Cho, J. H., Kim, H. S., 2012, Development of Technologies for Analysis of Thermo-fluid/ Combustion and Operations of Combustion System with Applications to a 100 MW-class Gas Turbine, Korea Institute of Machinery and Materials, Annual Report, Vol 3.

피인용 문헌

  1. Formation of Oxy-Fuel MILD Combustion under Different Operating Conditions vol.40, pp.9, 2016, https://doi.org/10.3795/KSME-B.2016.40.9.577