射频辅助脉冲电源驱动同轴介质阻挡放电脱除NOx的数值模拟研究

The automobile emissions have caused serious damage to the ecological environment. Both harmful organics and acid rain can be easily caused by the NOx, which is highly-riched and difficult-removed in series of harmful substances contained in the exhaust. In this project, the numerical study on removal of the NOx in the exhaust gas would be carried out based on low-temperature plasma techniques, and one new method that the dielectric barrier discharge driven by rf auxiliary pulse sources was proposed to remove the NOx in the exhaust gas. The species with highly ionization threshold would be decomposed by the high-energy electrons produced by the high-voltage pulse source; the temporal continuity and the spatial uniformity would be sustained and most of the substances would be dislodged by the low-voltage rf power. Under the guidance of this idea, one self-consistent fluid model would be developed to describe the physical and chemical reactions, and the produced species in the discharge of mixed gases (N2/O2/NOx) driven by rf auxiliary pulse sources in co-axial dielectric barrier electrodes; the removal efficiency of the NOx and the power conversion efficiency would be calculated; the influences of parameters including the power supply, the electrode dimensions, the barrier properties, and the H2O/CxHy contents on the NOx removal efficiency and the power conversion efficiency would also be researched. As purpose, the high-efficiency and energy-saving ways reducing the harmful substance in the exhaust gas would be explored. This project would have positive instructive functions for the industrialization process of the automobile tail gas treatment and the environment protection.

汽车尾气引起的雾霾等大气污染问题日益突出。尾气含有大量难以去除的NOx，易形成剧毒有机化合物和酸雨，对人体危害极大，是亟待解决的难题。本项目将基于低温等离子体介质阻挡放电技术，开展射频辅助脉冲电源驱动放电，去除尾气中NOx的数值模拟研究。采用脉冲电源调制电子密度和能量分布，高效地激发、分解电离阈能高的物种；用低幅值射频电源维持放电的时间连续性与空间均匀性，去除一般物种。在此思想的指导下，本项目将建立自洽的流体力学模型，研究同轴介质阻挡电极中，射频辅助脉冲电源驱动N2/O2/NOx放电的物理、化学反应过程，定量描述其中的物种成分；计算NOx去除效率及电源功率转化率；找出关键的反应通道和物种；研究外电源参数、电极结构参数、H2O(g)与CxHy的存在量对NOx去除效果的影响规律，进一步探索高效、节能地净化氮氧化物的途径。研究结果将对汽车尾气的工业化处理和环境保护工作具有积极的指导意义。

汽车尾气引起的雾霾等大气污染问题日益突出。尾气含有大量难以去除的NOx，易形成剧毒有机化合物和酸雨，对人体危害极大，是亟待解决的难题。本项目基于低温等离子体介质阻挡放电技术，开展射频辅助脉冲电源驱动放电，去除尾气中NOx的数值模拟研究。采用脉冲电源调制电子密度和能量分布，高效地激发、分解电离阈能高的物种；用低幅值射频电源维持放电的时间连续性与空间均匀性，去除一般物种。在此思想的指导下，本项目建立自洽的流体力学模型，研究同轴介质阻挡电极中，射频辅助脉冲电源驱动N2/O2/NOx放电的物理、化学反应过程，定量描述其中的物种成分；计算NOx去除效率及电源功率转化率；找出关键的反应通道和物种；研究外电源参数、电极结构参数等对NOx去除效果的影响规律，进一步探索高效、节能地净化氮氧化物的途径。研究结果将对汽车尾气的工业化处理和环境保护工作具有积极的指导意义。