PLIF and PIV Measurements of Jet Flames with Acoustically Forced Coaxial Air Jets

  • Han Jeong Jae (The Graduate school, School of Mechanical and Aerospace Engineering, Seoul National University) ;
  • Kim Munki (The Graduate school, School of Mechanical and Aerospace Engineering, Seoul National University) ;
  • Yun Sang Wook (The Graduate school, School of Mechanical and Aerospace Engineering, Seoul National University) ;
  • Yoon Youngbin (School of Mechanical and Aerospace Engineering, Seoul National University)
  • 발행 : 2005.12.01

초록

Acoustic excitations were imposed to coaxial air jet of non-premixed jet flame with hydrogen gaseous injected axially in the center of the flow. The frequencies of excitation were three dominant resonant frequencies at 1L, 2L, 3L. modes including specially 514 Hz (2L-mode) which was estimated theoretically as longitudinal mode of combustor characteristics. The mixing enhancement by acoustic forcing has been investigated quantitatively using PLIF and PIV. The effect of acoustic excitation on combustion process was significant to enhance mixing rate that coincides with specific resonant frequencies. And the behavior of vortex-interaction on flame structure was a good evidence to investigate the phenomenon of shear/mixing layer of fuel-air jet structure. The results obtained in this study concludes that generated streamwise vortex by acoustic excitation has a potential to enhance the mixing rate and abating NOx emissions.

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