TWC 老化特性数值仿真及优化研究摘要目前,汽车已经成为人们生活中重要的交通工具。为了控制汽车的尾气排放污染,保护人类赖以生存的大气环境,世界各国纷纷采取严格的汽车排放标准,针对汽车污染研发了各种技术措施和控制对策,其中汽油机三效催化转化技术是目前应用最多的净化技术。本文对三效催化转化器的基本结构及其工作原理进行了简要介绍,并分三效催化转化器的老化机理,对三效催化剂的失活机理做了进一步的阐述。运用采用 FLUENT 软件,按照快速老化条件进行求解,通过数值模拟,得出三效催化转化器的温度场以及氧浓度场的分布情况,结果表明老化时间对老化具有较大影响,三效催化转化器特征转化效率随着老化时间的增加而降低,并且在老化初期下降急剧,随着老化时间的增加特征转化效率的下降变缓。三效催化转化器起燃温度相比老化前要高出 60℃左右,起燃特性恶化,引起低速运转时排放量的大量增加。关键词:三效催化转化器;老化;反应机理;数值仿真AbstractAt present, the car has become an important traffic tool in people's lives. In order to control automobile exhaust pollution, protect human survival environment, countries around the world have taken stringent vehicle emission standards, developed for the automobile pollution of technical measures and control measures, the gasoline engine three-way catalytic conversion technology is currently the largest application of purification technology. The basic structure of the three-way catalytic converter and its working principle were briefly introduced, the aging mechanism of and three-way catalytic converter, of three-way catalyst deactivation mechanism further elaboration. Using FLUENT software, according to rapid aging conditions is solved, through numerical simulation, the three-way catalytic converter temperature field and oxygen concentration field distribution is obtained, and the results show that aging time on aging has a greater impact, characteristics of three-way catalytic converter conversion efficiency rate decreased wit...