[an error occurred while processing this directive]

Plasma Sci. Technol. ›› 2018, Vol. 20 ›› Issue (2): 24001-024001.doi: 10.1088/2058-6272/aa9850

• 18届全国等离子体科学和技术会议 •    下一篇

Investigation of flame structure in plasma-assisted turbulent premixed methane-air flame

  

  • 收稿日期:2017-06-20 出版日期:2018-01-11 发布日期:2017-11-06

Investigation of flame structure in plasma-assisted turbulent premixed methane-air flame

Hualei ZHANG (张华磊), Liming HE (何立明), Jinlu YU (于锦禄), Wentao QI (祁文涛) and Gaocheng CHEN (陈高成)   

  1. Science and Technology on Plasma Dynamics Lab, Air Force Engineering University, Xi’an 710038, People’s Republic of China
  • Received:2017-06-20 Online:2018-01-11 Published:2017-11-06
  • Supported by:

    This work was financed by National Natural Science Foundation of China (No. 51436008).

Abstract:

The mechanism of plasma-assisted combustion at increasing discharge voltage is investigated in detail at two distinctive system schemes (pretreatment of reactants and direct in situ discharge). OH-planar laser-induced fluorescence (PLIF) technique is used to diagnose the turbulent structure methane-air flame, and the experimental apparatus consists of dump burner, plasma-generating system, gas supply system and OH-PLIF system. Results have shown that the effect of pretreatment of reactants on flame can be categorized into three regimes: regime I for voltage lower than 6.6 kV; regime II for voltage between 6.6 and 11.1 kV; and regime III for voltage between 11.1 and 12.5 kV. In regime I, aerodynamic effect and slower oxidation of higher hydrocarbons generated around the inner electrode tip plays a dominate role, while in regime III, the temperature rising effect will probably superimpose on the chemical effect and amplify it. For wire-cylinder dielectric barrier discharge reactor with spatially uneven electric field, the amount of radicals and hydrocarbons are decreased monotonically in radial direction which affects the flame shape. With regard to in situ plasma discharge in flames, the discharge pattern changes from streamer type to glow type. Compared with the case of reactants pretreatment, the flame propagates further in the upstream direction. In the discharge region, the OH intensity is highest for in situ plasma assisted combustion, indicating that the plasma energy is coupled into flame reaction zone.

Key words: plasma assisted combustion, laser-induced fluorescence, flame structure, turbulent premixed combustion, dump burner

[an error occurred while processing this directive]