激光诱导荧光技术诊断大气压介质阻挡放电中OH时空分布

发布时间：2018-01-14 07:07

本文关键词：激光诱导荧光技术诊断大气压介质阻挡放电中OH时空分布　出处：《大连理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：本文主要介绍了使用时序非同步的激光诱导荧光(LIF)技术对大气压He-H20(0.4%)针-板介质阻挡放电(DBD)等离子体中基态OH自由基平均相对浓度进行测量,同时对OH平均相对浓度随外加电压的变化进行研究,并且利用ICCD成像系统对放电中的发射光谱和荧光光谱进行拍摄,通过发射光谱和荧光光谱的空间分布数据对OH自由基主要产生机制进行研究。本文主要研究内容包括：(1)设计和建立针-板介质阻挡放电系统和湿度调控系统,并将其与激光诱导荧光诊断系统进行整合最终实现OH自由基诊断。(2)利用时序非同步的L1F技术对针-板介质阻挡放电中OH自由基浓度相对涨落程度进行测量,结果显示所有的相对涨落均在±35%之内,其中约90%的荧光强度的相对涨落在±15%之内,并且随着外加电压的升高相对涨落逐渐减小,因此表明介质阻挡放电中OH平均相对浓度可以利用时序非同步的LIF技术进行测量。(3)在外加电压从1.4KV增加到4.OKV的过程中放电出现四种不同的模式,通过对四种模式的电压-电流波形图和ICCD放电成像分析可知放电模式分别为：负电晕介质阻挡放电、辉光放电、多脉冲辉光放电和丝状放电,并且对四种放电模式的放电机制进行了讨论。(4)利用时序非同步的LIF技术研究OH平均相对浓度随外加电压的变化,发现OH平均相对浓度随外加电压的升高同样分为四个区段,并且利用ICCD对放电中的发射光谱和OH荧光光谱进行成像,通过空间分布信息对四种放电模式中OH自由基产生机制进行研究,结果表明负电晕放电中OH自由基产生机制主要为电子直接碰撞解离过程,另外三种放电模式中OH自由基产生机制主要为He亚稳态的潘宁电离过程。(5)定义单位注入功率下OH产生效率,同时研究OH产生效率随外加电压的变化趋势,结果表明负电晕放电是单位注入功率下OH产生效率最高的放电模式,而丝状放电是OH产生效率最低的放电模式。
[Abstract]:This paper mainly introduces the synchronization of laser induced fluorescence (LIF) using non timing technology on atmospheric He-H20 (0.4%) needle plate dielectric barrier discharge (DBD) measurement of the average relative concentration of free radicals in the plasma of the ground state of OH, while the OH average relative concentration varying with the applied voltage are studied, and the use of ICCD imaging system the emission spectrum and fluorescence spectrum of discharge for the film, through the emission spectrum and fluorescence spectrum of the spatial distribution of data on the OH radical main mechanism were studied. The main contents of this paper include: (1) design and build a needle plate dielectric barrier discharge system and humidity control system, and the laser induced fluorescence the diagnosis system integration and ultimately OH radical diagnosis. (2) the use of non synchronous L1F technology on the discharge in OH radical concentration fluctuation extent of measurement block needle plate dielectric timing results Show all the relative fluctuation is within 35%, which is about 90% of the fluorescence intensity relative fluctuation is within 15%, and with the increase of applied voltage fluctuation decreases gradually, so that the dielectric barrier discharge OH average relative concentration can use timing synchronization technology of non LIF were measured. (3) an increase in the discharge voltage from 1.4KV to 4.OKV during the four different modes, the voltage of the four modes of current waveform and ICCD imaging analysis of discharge discharge mode respectively: negative corona dielectric barrier discharge, glow discharge, multi pulse glow and filamentary discharge, and the discharge mechanism of four kinds of discharge mode are discussed. (4) the use of sequential non OH study of LIF synchronous average relative concentration with the applied voltage changes, found that the average relative OH concentration with the increase of applied voltage is also divided into four sections , and the use of ICCD imaging of emission spectra and fluorescence spectra of OH in the discharge, the spatial distribution information of four kinds of OH radicals generated in the discharge mode, mechanism research, results show that the formation mechanism of OH radical negative corona discharge mainly electronic direct impact dissociation process, the other three OH free radicals in discharge mode the main mechanism of He metastable Penning ionization process. (5) the definition of unit power injection of OH and OH on the production efficiency, production efficiency with the applied voltage changes, results show that the negative corona discharge is a unit of injection power under OH mode discharge efficiency is the highest, which is OH filamentary discharge discharge mode efficiency is the lowest.

【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN249;O461.2

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