Experimental study of the low power arc discharge assisted methane combustion

doi:10.16568/j.0254-6086.201504015

Abstract

Abstract:

Different ratios of methane/air in the low power arc discharges assisted methane combustion were studied at atmospheric pressure. Plasma emission spectroscopy was recorded by an optical emission spectrometer. The possible physical and chemical reaction process and mechanisms were discussed. With a plasma in the on or off state, the physical appearances of the methane combustion flame were observed and compared, the temperature of the flame in the main combustion zone was investigated. The gas compositions of CH₄, CO and O₂ were analyzed by the gas chromatography and flue gas analyzer. The results showed that when plasma was in the on state, the temperature of flame increased and the combustion efficiency enhanced in stable combustion due to decrease of CH₄, CO and O₂; the combustion enhancement was more obvious at low ratio of methane/air; the rich combustion limits in terms of the ratio of methane/air was extended from 16% to 21%.

Key words: Optical emission spectroscopy, Rotational temperature, Gas chromatography, Concentration measurement

摘要：

利用低功率电弧放电辅助甲烷燃烧，研究了在不同甲烷/空气比例的情况下，等离子体对甲烷燃烧的影响。采用发射光谱仪进行光谱诊断，比较有/无等离子体辅助甲烷燃烧火焰发射光谱的异同，讨论了等离子体辅助燃烧可能发生的过程和机理。比较有/无等离子体辅助甲烷燃烧火焰温度的变化。利用气相色谱和烟气分析仪对甲烷燃烧产物中的CH₄、CO 和O₂ 进行分析。实验结果表明，加等离子体后，火焰的温度升高，尾气中的可燃性成分减少，氧气含量降低，在很大程度上提高了甲烷的燃烧效率；甲烷/空气的比例越低，燃烧效率的提高越明显；甲烷的富燃燃烧极限从16%调高到21%。

关键词: 发射光谱, 转动温度, 气相色谱, 浓度测量

CLC Number:

0539
O433.1

ZHANG Jun, FANG Shi-dong, SHU Xing-sheng, WANG Chuang, ZUO Xiao, MENG Yue-dong, WANG Shou-guo. Experimental study of the low power arc discharge assisted methane combustion[J]. NUCLEAR FUSION AND PLASMA PHYSICS, 2015, 35(4): 373-378.

张军，方世东*，舒兴胜，汪闯，左潇，孟月东，王守国. 低功率电弧放电辅助甲烷燃烧的实验研究[J]. 核聚变与等离子体物理, 2015, 35(4): 373-378.

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