物理化学学报 >> 2010, Vol. 26 >> Issue (01): 23-28.doi: 10.3866/PKU.WHXB20091216

化学动力学和分子动态学 上一篇    下一篇

二甲醚和乙醇低压层流预混火焰的对比研究

高健, 赵黛青, 汪小憨, 蒋利桥, 杨浩林, 袁涛, 杨玖重   

  1. 中国科学院广州能源研究所, 广州 510640; 中国科学技术大学国家同步辐射实验室, 合肥 230029; 中国科学院研究生院, 北京 100049
  • 收稿日期:2009-07-14 修回日期:2009-09-22 发布日期:2009-12-29
  • 通讯作者: 赵黛青 E-mail:zhaodq@ms.giec.ac.cn

Comparative Study of Dimethyl Ether and Ethanol Premixed Laminar Flames at Low Pressure

GAO Jian, ZHAO Dai-Qing, WANG Xiao-Han, JIANG Li-Qiao, YANG Hao-Lin, YUAN Tao, YANG Jiu-Zhong   

  1. Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, P. R. China; National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, P. R. China; Graduate University of Chinese Academy of Sciences, Beijing 100049, P. R. China
  • Received:2009-07-14 Revised:2009-09-22 Published:2009-12-29
  • Contact: ZHAO Dai-Qing E-mail:zhaodq@ms.giec.ac.cn

摘要:

利用分子束质谱结合真空紫外同步辐射光电离技术对相同燃烧条件下的低压层流预混二甲醚/氧气/氩气和乙醇/氧气/氩气火焰进行研究. 通过测量光电离效率曲线, 识别了二甲醚和乙醇火焰的中间物种, 得到相应的火焰质谱; 通过测量火焰中各物种在燃烧炉炉膛各位置的电离信号强度, 得到了各物种的摩尔分数分布曲线. 结合两种燃料分子不同的化学结构及详细的燃烧化学反应机理, 分析了两火焰中间物种生成特性的异同. 研究结果表明: 甲醛为两火焰中最主要的C1中间物种; 二甲醚火焰趋向于生成C1中间物种, C2物种摩尔分数较低; 乙醇火焰中乙醛、乙烯、乙炔和乙烯酮等C2中间物种的摩尔分数明显高于二甲醚火焰中的值.

关键词: 同步辐射, 单光子电离, 二甲醚, 乙醇, 层流预混火焰

Abstract:

Low pressure premixed laminar dimethyl ether (DME)/oxygen/argon and ethanol/oxygen/argon flames (equivalence ratio: 1.0) were studied by molecular-beam sampling mass spectrometry (MBMS) combined with the tunable synchrotron radiation photoionization technique. Combustion intermediates were identified by measuring photoionization efficiency (PIE) spectra, and the mole fraction profiles of these species at different flame positions were presented. Similarities and differences of main intermediate formation characteristics between the two flames were analyzed based on derived reaction mechanisms. Experimental results show that both flames contain the same intermediates such as CH3, CH4, C2H2, C2H4, CH2O, CH3OH, CH2=C=O, CH3CHO, and CH2CHOH. In the DME flame, the concentration of the C1 species is much higher than that of the C2 species, i.e., C1 intermediates tend to form rather than C2 intermediates in a DME flame. In addition, formaldehyde is the dominant C1 species in each flame. The concentrations of C2 species like ethylene, acetaldehyde, acetylene, and ketene in the ethanol flame are remarkably higher than that found in the DME flame.

Key words: Synchrotron radiation, Single-photon ionization, Dimethyl ether, Ethanol, Premixed laminar flame

MSC2000: 

  • O643