二甲醚/氢气稀混合气的着火特性  

Ignition Characteristics of Lean DME/H_2 Mixtures

作　　者：潘伦[1] 胡二江[1] 张自航 黄佐华[1] 

机构地区：[1]西安交通大学动力工程多相流国家重点实验室,西安710049

出　　处：《燃烧科学与技术》2014年第4期362-367,共6页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(51306144);天津大学内燃机燃烧学国家重点实验室开放课题资助项目(K2013-02)

摘　　要：利用激波管测量了二甲醚(DME)/氢气(H2)/氧气(O2)/氩气(Ar)稀混合气在宽广条件下的着火延迟期,并利用Chemkin软件对着火过程进行了模拟计算.实验结果表明,当混合气中H2的摩尔分数2HX<80%时,着火延迟期呈现出了典型的Arrhenius温度与压力依赖性;当80%<2HX<98%时,着火延迟期与温度仍呈现出Arrhenius关系,但是压力越高全局活化能越高;当2HX>98%时,着火延迟期与温度和压力都呈现出复杂的依赖关系.实验结果和计算结果均表明,随着H2混合比例增加,DME/H2混合气的着火延迟期呈现非线性的变化规律而且模型NUIG C4可以很好地预测出实验结果.通过自由基浓度分析和标准化H自由基消耗速率分析解释了上述现象.Ignition delay time of DME/H2/O2/Ar was measured under a wide condition using shock tube facility and the ignition process was modeled using Chemkin software. Results show that, when the mole fraction of H2 2HX 80%, ignition delay time shows a typical Arrhenius dependence on temperature and pressure. For 80%2HX 98%, ignition delay time only shows a typical Arrhenius dependence on temperature and ignition delay time at higher pressures gives higher ignition activation energy. However, for 2HX 98%, ignition delay time shows a complicated dependence on temperature and pressure. Both measured and calculated results indicate that H2 addition exhibits the nonlinear influence on the ignition delay time of DME/H2 mixtures and NUIG C4 model can well predict the experimental data. Chemically interpreting on the above effect was made using small radical mole fraction and normalized consumption of H radicals.

关 键 词：二甲醚(DME) H2 着火延迟期 化学反应动力学 

分 类 号：TK16[动力工程及工程热物理—热能工程]