NO是重要的大气污染物之一,为了深入了解脉冲介质阻挡放电去除N2/NO体系中NO的机理,采用一维自洽的流体力学模型对N2/NO中大气压脉冲放电进行了模拟研究,并分析讨论了各种放电参数对NO去除效率的影响。模拟结果表明:NO的去除主要通过还原反应N+NO→N2+O来实现;N原子是脱除NO的主要活性粒子,它来源于电压上升沿和下降沿的2次放电,并主要通过电子直接碰撞解离N2分子产生;放电中产生的N原子体积分数的高低直接决定NO的脱除效率;电压脉冲幅度越大,上升和下降时间越短,介质层越薄,或放电间隙越小,则脉冲放电产生的N原子体积分数就越高,越有利于NO的脱除;在其他参数不变时,存在1个最佳脉冲宽度,在此脉冲宽度下NO的脱除率最高。
NO is one of the important air pollutants. Based on one-dimension self-consistent fluid mode, the removal mechanism of NO from N2/NO mixture by pulsed dielectric-barrier discharge at atmospheric pressure was studied. The effects of the discharge parameters on NO removal rate were also investigated and discussed. Simulation results show that NO is removed mainly through the reaction N+NO→N2 +O. N atom is the main active species that removes the NO from N2/NO mixture. It comes from the two discharges occurring at the rising front and the falling front of applied voltage pulse, and it is mainly produced by the electron collision reaction with nitrogen which is the background gas. The NO removal rate depends on the concentration of N atom produced by pulsed dielectric barrier discharge (DBD)in N2/NO. The bigger the voltage amplitude, the shorter the rising and falling time, the thinner the dielectric layer, or the smaller the discharge gap, the higher the resultant N concentration and thus the higher the nitric oxide removal rate. When keeping other parameters unchanged, there exists an optimal voltage pulse width which results in the maximum NO removal rate.