發(fā)布時(shí)間：2018-04-10 22:34

  本文選題：脈沖介質(zhì)阻擋放電 + 放電等離子體　； 參考：《山東大學(xué)》2017年碩士論文

【摘要】：介質(zhì)阻擋放電是將絕緣介質(zhì)置于放電空間,常用于產(chǎn)生人工放電等離子體的一種氣體放電方式。而大氣壓脈沖介質(zhì)阻擋放電是一種由高壓脈沖激勵(lì)的新興的介質(zhì)阻擋放電方式,能夠兼具介質(zhì)阻擋放電和脈沖放電的優(yōu)良性能,在大氣壓下產(chǎn)生高化學(xué)活性的非熱平衡放電等離子體,完美地契合非熱平衡放電等離子體應(yīng)用領(lǐng)域中的實(shí)際需求,因此無論是從放電機(jī)理、特性等物理研究到等離子體生物醫(yī)學(xué)、材料改性等應(yīng)用研究都受到國內(nèi)外專家學(xué)者的廣泛關(guān)注。本論文建立并使用非熱平衡放電等離子體的一維流體模型,深入地研究了脈沖頻率對(duì)大氣壓氦氧與氬氧脈沖介質(zhì)阻擋放電等離子體的機(jī)理及特性的影響,并對(duì)大氣壓氬氧脈沖介質(zhì)阻擋放電等離子體中活性氧粒子生成機(jī)制開展了系統(tǒng)的研究。本文的研究工作,主要包含以下方面的內(nèi)容和結(jié)果。(1)使用一維流體模型,對(duì)2%氧濃度下大氣壓氦氧與氬氧脈沖介質(zhì)阻擋放電等離子體中放電電流密度、電場(chǎng)強(qiáng)度、平均電子溫度以及活性氧粒子的時(shí)空平均粒子密度的頻率效應(yīng)作了比較研究;研究了 5%的高氧濃度下大氣壓氬氧脈沖介質(zhì)阻擋放電等離子體中放電電流密度在1kHz-100kHz范圍的頻率效應(yīng),得到以下結(jié)論:無論是氦氧還是氬氧,一個(gè)電壓脈沖周期中均發(fā)生兩次極性相反的放電;頻率對(duì)氦氧中的兩次放電均有影響,而對(duì)氬氧中的第一次放電影響比較大,第二次放電影響很小;兩種放電氣體中,第一次放電峰值時(shí)刻的放電電流密度,平均電子密度和電場(chǎng)強(qiáng)度均隨著頻率的增加先減小后增大,存在一個(gè)特征頻率,在該頻率下具有最小值,且在氬氧中該特征頻率比氦氧中要小;在所考慮的放電條件下,與氦氧相比,氬氧中放電更強(qiáng),平均電子溫度更低。在同一頻率下,氬氧中的四種活性氧粒子的總生成量比氦氧中高出約一個(gè)數(shù)量級(jí)。在更高氧濃度下,氬氧第一次放電與第二次放電的放電電流密度峰值均隨著頻率的增加先減小后增大,存在相應(yīng)的特征頻率;在低于4%的氧濃度下,隨著氧濃度的增加,第一次放電的特征頻率呈現(xiàn)先增大后減小的變化,第二次放電的特征頻率一直持續(xù)增加,但在氧濃度高于4%時(shí),二特征頻率基本不變。(2)對(duì)一維流體模型的邊界作了優(yōu)化,使用該改進(jìn)的一維流體模型,對(duì)大氣壓氬氧脈沖介質(zhì)阻擋放電等離子體中活性氧粒子生成機(jī)制開展了系統(tǒng)的研究,研究?jī)?nèi)容包括氧濃度為3%時(shí)四種活性氧粒子生成與消耗的主要路徑及其在不同頻率下相應(yīng)的反應(yīng)貢獻(xiàn),以及氧濃度為1%時(shí)長(zhǎng)生存時(shí)間活性氧粒子的生成及調(diào)控機(jī)制,得到以下結(jié)論:氧濃度為3%時(shí),四種活性氧粒子生成與消耗的主要路徑研究中,不同頻率下O(1D)與O_2(1△g)的產(chǎn)生均主要來源于電子與O_2的碰撞;O的產(chǎn)生主要來源于電子與O_2的碰撞,其次是O(1D)與O_2的反應(yīng);O_3主要是通過O與O_2的反應(yīng)O_2+O_2+O→O_3+O_2產(chǎn)生。對(duì)于活性氧粒子的消耗,O(1D)主要是通過反應(yīng)O(1D)+O_2→O+O而消耗,且受頻率影響很小;O、O_2(1△g)和O_3的消耗路徑發(fā)生在幾個(gè)重要反應(yīng)之間,其反應(yīng)貢獻(xiàn)受頻率影響較大。在氧濃度為1%時(shí)長(zhǎng)生存時(shí)間活性氧粒子的生成及調(diào)控機(jī)制研究中,在一個(gè)完整脈沖周期內(nèi),電子e、Ar+、Arr、Arm和Ar*等粒子均主要生成于脈沖作用階段的上升沿和下降沿,并隨著脈沖的關(guān)斷迅速衰減為零,而O、O_2(1△g)和O_3三種活性氧粒子在脈沖關(guān)斷以后仍大量存在于氣隙中。O_3的空間平均粒子密度增大主要是源于反應(yīng)O_2+O_2+O→O_3+O_2對(duì)O_3的產(chǎn)生的主導(dǎo)貢獻(xiàn);O和O_2(1△g)的空間平均粒子密度增大則主要是因?yàn)樵谕馐┟}沖電壓作用下兩次放電相伴的電子e與O_2發(fā)生的碰撞引起的O和O_2(1△g)的產(chǎn)生的驟增。
[Abstract]:Dielectric barrier discharge is the insulating medium is arranged inside the discharge space, a gas discharge mode used to produce artificial plasma. Atmospheric pressure pulsed dielectric barrier discharge is composed of a high voltage pulse excitation of the new dielectric barrier discharge, excellent performance can both dielectric barrier discharge and pulse discharge, non thermal equilibrium plasma discharge high chemical activity under atmospheric pressure, perfectly fit the actual demand application of the non thermal equilibrium in the discharge plasma, so whether it is from the discharge mechanism, physical characteristics to plasma biomedical, widely concerned by domestic and foreign experts and scholars of the application research of modified materials. This paper establish and use the non thermal equilibrium a one-dimensional fluid model of the discharge plasma, in-depth study of the pulse frequency on the atmospheric pressure helium oxygen and argon oxygen pulse dielectric barrier discharge plasma The influence mechanism and characteristics of progeny, and the atmospheric pressure argon oxygen pulse to carry out a systematic study of dielectric barrier discharge plasma reactive oxygen species generation mechanism. The research work of this thesis, the main contents and results include the following aspects. (1) using a one-dimensional fluid model of 2% oxygen under atmospheric pressure helium and oxygen argon oxygen pulse dielectric barrier discharge plasma discharge current density, electric field intensity, the average electron temperature and time of active oxygen particles average particle density frequency effect are studied; the effects of high oxygen concentration 5% under atmospheric pressure argon oxygen pulse dielectric barrier discharge plasma discharge current density frequency effect in the range of 1kHz-100kHz, get the following conclusions: both the helium oxygen or argon oxygen, a voltage pulse cycle are two opposite polarity discharge; the two discharge can influence the frequency of helium and oxygen, and The relatively large first discharge effect of argon and oxygen in the second movie sound is very small; two kinds of gas discharge, the first discharge peak discharge current density, the average electron density and the electric field strength with the increase of frequency decreases first and then increases, there is a characteristic frequency, with a minimum at the frequency and, in the characteristic frequency ratio of argon and oxygen in helium oxygen should be small; in the discharge conditions, compared with helium oxygen, argon oxygen discharge stronger, the average electron temperature is lower. At the same frequency, the total production of four kinds of reactive oxygen species in the argon oxygen about a order of magnitude higher than helium oxygen. At higher oxygen concentration, oxygen argon discharge and the first second discharge current density peak value with the increase of frequency decreases first and then increases, the corresponding characteristic frequency; the oxygen concentration is below 4%, with the increase of oxygen concentration, the first The characteristics of electrical frequency changes increased first and then decreased, the characteristic frequency second times discharge has continued to increase, but when the oxygen concentration is higher than 4%, two characteristic frequency basically unchanged. (2) of a one-dimensional fluid model boundary were optimized using a one-dimensional fluid model, the improvement of atmospheric pressure argon, oxygen pulse to carry out a systematic study of dielectric barrier discharge plasma reactive oxygen species generation mechanism, research content including the oxygen concentration is 3% the main path of four kinds of reactive oxygen species generation and consumption and its contribution to the corresponding reaction at different frequencies, and the oxygen concentration of 1% long survival time of reactive oxygen species generation and regulation mechanism, are as follows conclusion: when the oxygen concentration was 3%, the main research path of four kinds of reactive oxygen species generation and consumption in different frequency O (1D) and O_2 (1 g) is produced mainly from electronic and O_2 collision; the production of O 涓昏鏉ユ簮浜庣數(shù)瀛愪笌O_2鐨勭鎾，

本文編號(hào)：1733196