温度、还原剂含量及水蒸气含量对氮氧化物存储还原技术NO排放的影响  

Effects of Temperature,Reducing Agent Concentration and Water Vapor on NO Emission of Hydrogen Fuel Engines Using NO_(x) Storage and Reduction Technology

作　　者：潘朋 温溢[2] 苏智阳[1,2] 李世龙 李振国 李志军[1] PAN Peng;WEN Yi;SU Zhiyang;LI Shilong;LI Zhenguo;LI Zhijun(State Key Laboratory of Engines,Tianjin University,Tianjin 300072,China;China Automotive Technology and Research Center Co.,Ltd.,Tianjin 300300,China)

机构地区：[1]天津大学内燃机燃烧学国家重点实验室,天津300072 [2]中国汽车技术研究中心有限公司,天津300300

出　　处：《西安交通大学学报》2023年第11期82-90,共9页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(51976136);清华大学汽车安全与节能国家重点实验室开放基金资助项目(KF1818)。

摘　　要：为探究氮氧化物存储还原(NSR)催化器在氢燃料发动机不同工况下NO排放的控制效果,基于氢燃料发动机台架实验的原排放数据,结合NSR机理建立了适用于氢燃料发动机NO_(x)后处理的H 2-NSR反应机理动力学模型。基于该模型,对比分析了氢燃料发动机NSR后处理器不同入口温度、还原剂含量和水蒸气含量对NO排放的影响,发现温度降低有利于NO吸附,但却会导致还原阶段NO排放增加;吸附阶段NO的排放随还原剂含量增加而减少,但还原阶段NO的排放则会增加;而水蒸气对NSR催化器催化还原NO有促进和抑制作用。结合敏感性系数分析等手段从化学反应动力学的角度揭示了温度、还原剂含量及水蒸气含量对NO排放的影响的产生原因,并明确了温度是其中的主导因素。所提出的H 2-NSR机理动力学模型为氢燃料发动机控制NO排放提供了理论参考。This paper aims to investigate the control effect of nitrogen oxide(NO_(x))storage and reduction(NSR)catalyst on the NO emissions of hydrogen fuel engines under different operating conditions.To this end,a kinetic model of the H_(2)-NSR reaction mechanism was established for the NO_(x) after-treatment in hydrogen fuel engines,based on the original emission data obtained from bench tests of these engines and in combination with the NSR mechanism.Using this model,the effects on NO emissions by different inlet temperatures,reducing agent concentrations and water vapor concentrations of the NSR after-treatment devices of the hydrogen fuel engines were compared and analyzed.The results showed that a temperature drop could facilitate NO absorption but would increase NO emission during the reduction phase;increasing the reducing agent concentration would lead to an increase of NO emission during the adsorption phase and a decline of NO emission during the reduction phase;and water vapor had a promoting and inhibiting effect on the catalytic reduction of NO in the NSR catalyst.Finally,sensitivity analysis and other methods were used to reveal the cause of its occurrence from the perspective of chemical reaction kinetics,finding that temperature is the dominant factor.The proposed H_(2)-NSR mechanism dynamics model provides an important theoretical reference for hydrogen fuel engines to control NO emissions.

关 键 词：氢燃料发动机 氮氧化物存储还原 NO排放 催化器 

分 类 号：TK46[动力工程及工程热物理—动力机械及工程]