Stability limits of premixed microflames at elevated temperatures

고온에서의 예혼합 초소형 화염의 연소안정한계 연구

  • Kim, Ki-Baek (School of Mechanical Engineering, Sungkyunkwan University) ;
  • Lee, Kyoung-Ho (School of Mechanical Engineering, Sungkyunkwan University) ;
  • Hong, Young-Taek (School of Mechanical Engineering, Sungkyunkwan University) ;
  • Kwon, Oh-Chae (School of Mechanical Engineering, Sungkyunkwan University)
  • 김기백 (성균관대학교 기계공학부) ;
  • 이경호 (성균관대학교 기계공학부) ;
  • 홍영택 (성균관대학교 기계공학부) ;
  • 권오채 (성균관대학교 기계공학부)
  • Published : 2006.06.15

Abstract

In order to provide the database for designing microcombustors, the combustion characteristics of premixed methane and propane air microflames at normal and elevated temperatures and atmospheric pressure generated on a microtube were studied experimentally and computationally. The stability limits of premixed microflames and the propensity of the microflames near the stability limits were experimentally determined, while the structure of the microflame at the fuel-leanest limit was obtained using a two-dimensional CFD simulation with a reduced kinetic mechanism. For all the microflames, the stability limits were observed only in the fuel-rich region. Results also show substantial extension of stability limits with elevated temperature that is realistic condition for micro fuel processing and significant fuel dilution immediately near the tube exit due to a low Peclet number times Lewis number effect.

Keywords

Microcombustors;Micro fuel processing;Microflames;Stability limits

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