基于臭氧添加的低温氧化反应动力学实验和模型研究

低温燃烧技术的进步依赖于低温化学反应动力学的发展。臭氧掺混辅助燃烧可以在低温区域为体系提供氧自由基，有效降低起始反应温度，增强低温反应活性，将氧化过程拓展到更低温度范围。本项目拟将臭氧发生装置与快速压缩机实验平台结合，将快速压缩机的研究工况拓展到低温高压区域，测量燃料着火延迟时间，并利用气相色谱和超快时间分辨质谱对低温着火过程中的物种浓度变化进行测量；拟将臭氧发生装置与射流搅拌反应器结合，利用同步辐射光电离-分子束质谱诊断方法对氧化过程的中间稳定组分和过氧化物进行定性和定量测量。选取自身低温反应活性弱的含氧小分子如甲醇、乙醇、甲基叔丁基醚，以及支链烷烃如异丁烷、异辛烷为研究体系，在臭氧掺混下对其低温氧化过程中的组分进行全面诊断。基于物种浓度信息，结合模型反应流量分析及敏感性分析，对可能缺失的低温反应路径进行补充，降低反应分支比及反应速率常数的不确定性，最终完善低温化学反应动力学模型。

The development of low temperature combustion (LTC) is based on the understanding of low temperature oxidation chemical kinetic. Ozone addition assistant combustion can increase the low temperature reactivity due to the oxygen radical produced through ozone decomposition. With the help of ozone addition, a low temperature and high pressure condition can be achieved in a rapid compression machine (RCM). Ignition delay time and concentration profile of intermediate species will be quantified based on pressure measurement and gas chromatography/high repetition rate mass spectrometry. To investigate the low temperature behavior in a lower temperature range, an ozone generation and concentration measurement system will be coupled with a jet stirred reactor (JSR). Based on synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS), the mole fraction of low temperature oxidation intermediate species including hydrogen peroxide, alkyl hydroperoxides and ketohydroperoxides will be measured. The program is intended to make a comprehensive study low temperature oxidation behavior of small oxygenate molecular like methanol, ethanol, methyl tert-butyl ether and branched alkanes like iso-butane and iso-octane, which have little low temperature reactivity. Based on the detailed speciation information, together with modeling rate production and sensitivity analysis, the low temperature oxidation pathways and reaction rates will be improved.