空气高压放电紫外特性及多光谱成像技术研究

发布时间：2018-03-25 19:00

本文选题：空气放电　切入点：等离子体　出处：《中国科学院研究生院(上海技术物理研究所)》2016年博士论文

【摘要】：气体高压放电等离子体是国际研究的热点。通过气体放电可以产生等离子体,可以应用于照明、纳米技术、生物医学、环境保护、表面材料等领域,但一个大气压下空气中电弧/电晕的产生会对电力系统、高电压电气设备造成电力流失和持续的破坏,故大气压下空气放电等离子体的产生有利有弊,因此对大气压下空气放电等离子体目标开展关于其参数和特性的研究,是很有必要的。本文的主要研究内容,针对大气压下空气高电压放电等离子体目标,分析了其生成的原理,概述了汤森理论和流注理论,阐述了其在大气压下放电的过程是一致的,从汤森放电简单的空气击穿,迅速发展成稳定的自持式放电。通过自行搭建的空气高压放电目标的紫外光谱探测系统,开展对目标的紫外光谱实验,完成了200nm-1000nm之间的光谱测量,分析并发现了空气高压放电等离子体(电弧/电晕)的光谱分布主要集中在200nm-400nm的紫外波段,并且其发射光谱的特征峰值与氮气离子激发态的发射光谱特征密切相关。其次,开展了关于放电等离子体目标的模拟仿真,通过构建三个不同的结构,基于三大基本物理原理模型,获得大气压下放电的微观过程,包括氮气离子激发态N2+的质量密度分布等。基于上述分析,针对空气高压放电目标,提出了紫外多光谱的成像技术手段,搭建了紫外多光谱的成像系统总体方案,其中包含了设计带有滤光轮的光学子系统,对比选型后选用了紫外增强型背照减薄式CCD探测器器件,设计了低噪声高密集度的电路和FPGA驱动逻辑时序设计,搭载设计了三速以太网中的GigE数据传输手段,设计实现了基于WinpCap库的以太网数据帧接收的上位机软件和大数据分包回放软件。完成了系统的安装、光校,获得较好的图像质量,通过氙灯积分球辐射定标方法,并获得系统目标反演的模型。使用不同的高压放电目标发生器,针对电弧/电晕开展了目标成像实验,反演得到目标的辐亮度,并将系统响应与放电电压值、空间间隙距离和积分时间的关系进行了相关研究。本文的创新点包括:1)在系统设计的规划上,针对成像目标从简单的发光目标提升到空气放电低温等离子体的高度,从放电目标的产生过程和原理去解析目标的紫外辐射特性,完成了对空气高压放电目标的紫外光谱探测与分析,并利用空气放电过程的三大物理原理级模型(粒子动理学、流体力学及混合模型),通过数值仿真软件进行有限元分析仿真,以此得到与放电过程发射光谱相吻合的结果。基于经典的棒板模型构造的非均匀电场分布,探索性地提出了同样为非均匀电场分布的棒棒模型,提出了一维结构和二维的结构,完成了对应的仿真。获得了空气放电分布强度仿真结果,与成像结果相印证。2)提出了适用于空气高压放电目标的紫外多光谱成像系统整体方案,并研制了原理样机,包含240nm-280nm,280nm-325nm,315nm-340nm三个紫外波段,充分利用了空气放电目标的紫外发射光谱特征,获取多谱段成像信息;同时具备在不同应用场合中对指定的紫外目标进行紫外多光谱的成像实验研究。其中主要包括,带有滤光轮的光学选择系统,带有低噪声高灵敏度的紫外增强型背照减薄式CCD探测器,高效紧凑的电子电路及FPGA驱动技术,符合数据传输需求、保存和图像显示的多线程上位机软件以及大数据分包回放软件。3)针对空气高压放电目标(电弧/电晕)完成了紫外多光谱的成像实验,对不同结构模型不同放电发生器下产生的电弧目标成像,研究分析了关于电压值、空气间隙、积分时间的关系,与仿真结果相吻合。通过氙灯积分球定标后的目标辐亮度反演模型,得到放电等离子体目标的辐亮度。为后续开展空气高压放电更为深入的研究奠定了坚实的紫外相关技术和实验基础。
[Abstract]:High pressure gas discharge plasma is an international research hotspot. Through the gas discharge plasma can be generated, can be used in lighting, nanotechnology, biomedical, environmental protection, field surface material, but a large pressure in the air to produce power system / corona arc, high voltage electrical equipment caused by power loss and sustained the destruction of air discharge plasma under atmospheric pressure generated to carry out research on the There are both advantages and disadvantages., therefore the parameters and characteristics of the target air plasma discharge at atmospheric pressure, is very necessary. The main contents of this paper, aiming at the goal of high voltage air discharge plasma at atmospheric pressure, analyzes its formation principle, summarizes the Townsend the theory and the streamer theory, expounds its discharge under atmospheric pressure process is consistent, from the air breakdown Townsend simple, rapid development into a stable A self-contained discharge. The UV spectrum through the high-pressure air discharge target to build their own detection system, to carry out the experimental UV spectra of target, complete spectral measurements between 200nm-1000nm, analyzed and found the high-pressure air discharge plasma (ARC / corona) spectral distribution mainly concentrated in the ultraviolet band 200nm-400nm, emission spectrum the characteristics and the emission spectrum of nitrogen ion characteristic peak and excited states are closely related. Secondly, to carry out the simulation of discharge plasma target, through the construction of three different structures, three basic physical principle based on the model, obtain the microscopic process of discharge under atmospheric pressure, including the excited state N2+ nitrogen ion mass density distribution. Based on the above analysis, in view of the high-pressure air discharge, put forward the means of UV imaging technology in multi spectral imaging system is built, the total ultraviolet multispectral Scheme, including design subsystem with optical filter wheel, after the comparison and selection of UV enhanced thin backlight type CCD detector device, designed a low noise high density circuit and FPGA logic timing design, GigE data transmission means three speed Ethernet Design equipped with design and implementation the PC software of Ethernet data frames received by the WinpCap library and data packet replay based software. Completed the system installation, calibration, good image quality, calibration method by integrating sphere radiation and xenon lamp, get the system object inversion model. Using the high voltage discharge target generator for arc / different. Corona carried out target imaging experiments, inversion to obtain the target radiance, and the system response and discharge voltage, gap distance and space integral time was studied. The innovation of this paper Include: 1) in the system design plan, according to the imaging target from simple light to air target plasma level, from ultraviolet radiation properties and the principle to resolve target discharge targets, completed the UV detection and analysis of the high-pressure air discharge target, and use three high level physical principle model of air discharge process (particle kinetic theory, fluid mechanics and mixture model), finite element simulation analysis by numerical simulation software, in order to get and discharge emission spectrum. The results. Based on the classical rod plate model constructed non uniform electric field distribution, is put forward for the same non uniform electric field distribution model of bang bang, put forward the structure of one-dimensional and two-dimensional structure, completed the corresponding simulation. The simulation results of air discharge intensity distribution was obtained, and the imaging result confirmed by.2 The UV) is applicable to the high-pressure air discharge target multi spectral imaging system overall scheme, and developed the principle prototype, including 240nm-280nm, 280nm-325nm, 315nm-340nm three UV band, make full use of the ultraviolet air discharge target emissivity spectral features, obtaining multi spectral imaging information; experimental study on imaging with purple outside of the specified ultraviolet target in different applications in multispectral. Which mainly include the system with optical filter wheel selection, with low noise and high sensitivity of UV enhanced thin backlight type CCD detector, high efficient and compact electronic circuit and FPGA drive technology, meet the needs of data transmission, multi thread the PC software and save the image display and data playback software package.3) for the high-pressure air discharge target (ARC / corona) imaging ultraviolet multispectral experiments on different structure The target model of different imaging arc discharge generator, analysis on voltage, air gap, the relationship between integral time, consistent with the simulation results. The target radiance inversion model of integral sphere calibration after xenon lamp, by discharge plasma target radiance. UV and related technology laid a solid experimental basis the further research for the following high-pressure air discharge.

【学位授予单位】：中国科学院研究生院(上海技术物理研究所)
【学位级别】：博士
【学位授予年份】：2016
【分类号】：O461;O53

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