DEVELOPMENT OF COMPACT EXHUST GAS TREATMENT EQUIPMENT FOR DIESEL ENGINE USING DIELECTRIC BARRIER DISCHARGE

本项目的目的是通过表面处理（清洗、涂层）和/或表面精炼（离子注入）来细化三维复杂材料，如模具金属框架，利用高重复脉冲调制器产生大容量和高密度辉光等离子体和脉冲偏置提取离子的组合。为了实现这一目的，本项目分为以下三个主题。(1)第一步是掌握等离子体进入材料的热流密度和脉冲辉光放电的等离子体参数。(2)第二步是开发用于等离子体产生和偏置电压供应的脉冲调制器。(3)三是流体模型的数值模拟。结果如下：1。通过探针测量、电流-电压特性和光谱分析，阐明了脉冲辉光放电的等离子体参数。等离子体密度为3 × 10^<11> cm^<-3>，持续时间约为8 μs。在此期间，等离子体温度从450℃上升到650℃。温度的升高产生了热流。计算了热流密度与输入功率的比值，发现该比值约为40%。将SOS二极管与感应储能系统相结合，研制了超薄薄膜中离子提取脉冲发生器，用于离子基质向玻姆薄膜过渡前的离子提取。脉冲发生器的规格为输出电压- 20kv，重复频率数百Hz，脉冲宽度60ns。脉冲宽度较玻姆峰形成时间（1 μs）短。对二维流体模型进行了数值分析。结果表明，保护电极材料抗电蚀的接地封层对等离子体的特殊分布有明显的改变。等离子体分布的探针测量结果与数值计算相吻合。我们还利用化学反应模型分析了离子数密度。在含氮情况下，该反应以N_2^+和N_4^+为主。少

The purpose of this project is to refine a three dimensional complex material, like the mold metal frame, by the surface treatment (cleaning, coating) and/or surface refining (ion implantation), making use of the combination of high repetitive pulse modulator for large capacity and high density glow plasma generation and pulse biasing for extraction of ions. The project was performed in the following three subjects to realize the purpose. (1) The first step is to grasp the heat flux from plasma into the material and plasma parameter of the pulsed glow discharge. (2) The second step is to develop a pulse modulator for plasma generation and bias voltage supply. (3) The third is the numerical simulation by the fluid modeling. The results are as follows.1. It was clarified that the plasma parameter of the pulsed glow discharge by probe measurement, current-voltage characteristics, and the spectroscopic analysis. The plasma density 3 x 10^<11> cm^<-3> was sustained over a period of 8 μs app … More roximately. The plasma temperature has increased form 450 ℃ to 650 ℃ in this period. This temperature rise generate the heat flux. Estimating the ratio of the heat flux to the input power, it was found that the ratio came up to 40 % approximately.2. Combining the SOS diode and inductive energy storage system, we produce the pulse generator for ion extraction from ultra thin theath, before the transition form ion matrix to Bohm theath. The specification of the pulse generator are output voltage -20 kV, repetition frequency hundreds Hz, and pulse width 60 ns. The pulse width is short enough compared with the Bohm theath formation time(1 μs).3. The numerical analysis of the 2D fluid model was progressed. It was found that the special plasma distribution was remarkable modified by the earth sealed which guard the electrode material to the suputtering. The probe measurement result of the plasma distribution was consistent with the numerical calculation. We also analyzed the ion number density making use of the chemical reaction models. In nitrogen cases, it was found that N_2^+ and N_4^+ are dominated in this reaction. Less