论文部分内容阅读
非平衡等离子点火是一种利用非平衡等离子体的化学效应和热效应来引燃混合物的新型点火方式.具有拓宽稀燃极限、降低点火延迟等优点,近年来引起研究人员的关注.等离子体是一个带电粒子的复杂系统,粒子间存在电离、激发、离解、电荷转移等复杂的相互作用.本文分析了非平衡等离子体中电子影响下的碰撞,以氮氧混合物为例模拟了约化电场强度高于100 Td时电子对分子的激发和电离作用.采用高约化电场强度下的简化机理,对氮气氧气中的介质阻挡放电过程进行了模拟,分析了激发态粒子的产生和O自由的生成过程.“,”Nonequilibrium plasma assisted ignition is a way to ignite combustible mixtures due to the chemical and thermal effect of plasma.The nonequilibrium plasma assisted ignition can extend the lean burn limits and reduce the ignition delay time.Recently,the potential use of nonequilibrium plasma for increasing lean burn flame stability and reducing emissions has garnered increasing interest of researchers.Plasma is a complicated system of neutral and charged particles with various interactions such as ionization,excitation,dissociation and charge transfer.In this thesis,an insight in to the electron-impact collisions in nonequilibrium plasmas is provided,a nanosecond discharge process in a mixture of nitrogen and oxygen was simulated with a simplified kinetics for a high reduced electric field (＞100 Td).The formation of O radical and other excited states were analyzed.