低温等离子体增强催化氨合成机理的一维流体动力学模型  

1D Fluid Model of Catalytic Ammonia Synthesis Enhanced by Low Temperature Plasma

作　　者：陈赦[1,2] 刘红梅 吴婷 汪沨[1] 庄池杰[2] Chen She;Liu Hongmei;Wu Ting;Wang Feng;Zhuang Chijie(College of Electrical and Information Engineering Hunan University, Changsha 410082 China;State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Department of Electrical Engineering Tsinghua University,Beijing 100084 China)

机构地区：[1]湖南大学电气与信息工程学院,长沙410082 [2]电力系统及大型发电设备安全控制和仿真国家重点实验室(清华大学电机系),北京100084

出　　处：《电工技术学报》2021年第13期2730-2739,共10页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(51977063);湖南省自然科学基金(2020JJ5053);电力系统国家重点实验室开放课题(SKLD19KZ01)资助项目。

摘　　要：氨在化工及能源储存领域有巨大的应用价值。低温等离子体使反应在温和条件下进行,对促进氨的生成起着重要作用。以往零维动力学模型研究中电场和电子密度作为输入参数,它的空间信息被忽略,因此需要进一步建模来深入研究等离子体增强催化机理。该文建立大气压板-板电极下的等离子体增强催化氨合成的一维流体动力学模型。模型考虑了47种粒子和379种反应(包括气相和催化剂表面的多相反应),显示了影响氨产量关键参数如电场强度、电子能量和电子密度的空间分布。讨论了电压大小、N_(2)H_(2)比例和催化剂表面自由位点密度对氨合成的影响。仿真结果显示,随着外加电压的增加,氨气产量先增加后减小;N_(2)H_(2)比例为12时有利于氨的合成;当表面活性位点数目从10^(14)cm^(-2)增加到10^(18)cm^(-2)时,氨气产量增加比例约为9.89%。Ammonia has great application potential in the fields of chemical industry and energy storage.Low temperature plasma makes the reaction occur under mild conditions and has been experimentally proven to play an important role in enhanced-catalytic formation of ammonia.In the previous studies,the electric field and electron density were used as input parameters in the zero-dimensional kinetic models.However,their spatial information was ignored.Therefore,further modeling is needed to study the plasma catalysis mechanism.In this paper,a 1D fluid model of plasma-assisted catalytic ammonia synthesis is built under a plate-plate electrode configuration at atmospheric pressure.In the model,47 species and 379 reactions,including gas-phase and hetero-geneous reactions on catalytic surface,are considered.The distribution of electric field,electron energy and electron density which affect the ammonia production are obtained.Furthermore,the effects of applied voltage,N_(2)H_(2) ratio content and free site density of catalyst surface on ammonia synthesis are discussed.The simulation results show that the ammonia yield first increases and then decreases as the applied voltage increases.The N_(2)H_(2) ratio of 12 is favor to the ammonia production.When the surface site density increases from10^(14) to 10^(18)cm^(-2),the increase in ammonia yield is about 9.89%.

关 键 词：低温等离子体 催化 氨合成 流体动力学模型 

分 类 号：O53[理学—等离子体物理] TM8[理学—物理]