Oxy-Steam燃烧方式下的NO生成特性  

NO Formation Mechanism During Oxy-Steam Combustion

作　　者：张明伟[1] 何一卓 宋昱[2] 陈武忠[2] 罗江辉 邹春[2] 郑军妹 郑楚光[2] Zhang Mingwei;He Yizhuo;Song Yu;Chen Wuzhong;Luo Jianghui;Zou Chun;Zheng Junmei;Zheng Chuguang(China Quality Supervision&Test Center for Gas Appliances(Foshan),Foshan 528000,China;State Key Laboratory of Coal Combustion,Huazhong University of Science and Technology,Wuhan 430074,China;Key Laboratory of Healthy&Intelligent Kitchen System Integration of Zhejiang Province,Ningbo 315336,China)

机构地区：[1]国家燃气用具产品质量监督检验中心(佛山),佛山528000 [2]华中科技大学煤燃烧国家重点实验室,武汉430074 [3]浙江省健康智慧厨房系统集成重点实验室,宁波315336

出　　处：《燃烧科学与技术》2018年第1期89-95,共7页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(51176055;50936001);教育部创新团队发展计划资助项目(50721005)

摘　　要：以甲烷掺混氨气为燃料对oxy-steam气氛下NO生成特性进行实验和模拟研究.在常压柱塞流反应器中开展了一系列O_2/N_2和O_2/H_2O气氛的对比实验,当量比从富燃至贫燃(1.6、1.0、0.2),温度范围为973~1,773,K.实验结果表明,O2/H_2O气氛下高浓度的水蒸气在当量和贫燃工况下抑制NO的生成,而在富燃工况下促进NO生成.更新并构建的详细化学机理能够很好地重现并解释实验中NO的生成特性.当量和贫燃工况下,极少的O基团抑制了反应NH_2+O H+HNO从而抑制了NH_2→HNO→NO反应路径,最终降低了NO的生成.富燃工况下,充足的OH基团显著促进了反应NH_2+OH=NH+H_2O从而促进了NH_2→NH→HNO→NO反应路径,最终增加了NO的生成.The effect of high H2O concentration during oxy-steam combustion on the oxidation of methane and ammonia was investigated both experimentally and numerically.Comparative experiments between O2/N2 and O2/H2O atmospheres were performed in a flow reactor at atmospheric pressure covering fuel-rich to fuel-lean equivalence ratios and within the temperature range from 973 K to 1,773 K.Experimental results showed that high H2O concentrations inhibited NO formation under stoichiometric and fuel-lean conditions but enhanced NO formation under fuel-rich conditions.The chemical kinetic mechanism,which was hierarchically structured and updated,satisfactorily reproduced the main characteristics of NO formation.High H2O concentrations significantly enhanced H+H2O=OH+H2 and O+H2O=OH+OH,leading to substantially higher OH concentrations and lower O concentrations in the O2/H2O atmosphere than those in the O2/N2 atmosphere.NO suppressions under stoichiometric and fuel-lean conditions were caused by strong suppression of NH2+OH+HNO in the pathway NH2→HNO→NO.This suppression is due to the lack of O radicals.By contrast,NO enhancement under fuel-rich conditions was caused by the significant enhancement of NH2+OH=NH+H2O in the pathway NH2→NH→HNO→NO.This enhancement is due to the fairly high OH concentration in the O2/H2O atmosphere.

关 键 词：oxy-steam燃烧 化学反应机理 柱塞流反应器 NO 

分 类 号：TK123[动力工程及工程热物理—工程热物理]