甲烷/空气混合气体在针板电极下的微间隙放电特性

doi:10.19595/j.cnki.1000-6753.tces.220560

Abstract
Figure/Table
References
Related Citation (15)

Download: PDF (4673 KB) HTML (1 KB)
Export: BibTeX | EndNote (RIS)

Abstract Electrical equipment working in explosive environment should meet the requirements of intrinsic safety. Domestic and foreign scholars evaluate the intrinsic safety based on the voltage and current characteristic curves of the discharge measured by IEC-SSTA spark test device. However, the discharge mechanism and particle change law in case of equipment failure are not clear. In the design of intrinsically safe electrical equipment, there will be transition explosion-proof, which limits the improvement of intrinsically safe output power, resulting in that the output power of intrinsically safe equipment can only reach about 20 W. Therefore, based on the electrode structure of the program-controlled micro-nano discharge test device, the discharge physical model is established in the methane-air mixture environment. The discharge parameters such as axial electron density, various positive ion density and so on are obtained by two-dimensional modeling and simulation of the discharge through hydrodynamics, thus clarifying the discharge mechanism of plasma micro-gap.
Firstly, a two-dimensional discharge model is established based on the electrode structure, and the boundary conditions are set. Secondly, add the chemical reaction equation and set the conditions such as the cross section data involved in the reaction. Then, set the initial gas concentration and particle density. Finally, the simulation is carried out to obtain the data by changing the electrode distance and the concentration of methane-air mixture. According to the simulation, the influence of the change on the electron density, the number density of positive ions, the electric field strength and the average electron energy is analyzed, and the micro-gap discharge mechanism is analyzed from the microscopic level.
At the initial stage of discharge, the degree of electron collision ionization reaction between the electrons in the electrode gap and other gas molecules is relatively low, and the electron density is in a slow rising stage. As the energy gained by the electrons in the electric field increases, the collision ionization becomes more and more intense, and the electron density increases rapidly. With the development of motion, the probability of recombination of electrons and positive ions also increases, which slows the growth of electron density. In general, the electron density first increased to the peak and then decreased, and the discharge continued to develop and gradually entered a stable stage. Then change the pole spacing to get the conclusion that the pin-plate spacing not only affects the particle impact ionization degree, but also affects the discharge mechanism. When the needle plate spacing is greater than or equal to 10 μm, there is no field emission in the discharge process. After changing the concentration of methane, it can be concluded that the contribution rate of O₂ and CH₄ to the discharge is greater than that of N₂, and the discharge is mainly the collision ionization of O₂and CH₄. Finally, experimental verification is carried out. The experimental results are consistent with the simulation results, which verify the correctness of the theoretical analysis.
The following conclusions can be drawn from the simulation analysis: (1) During micro-gap discharge, sheath area will be formed at about 2 μm of the positive electrode and about 0.5 μm of the negative electrode. The positive ion sheath area near the cathode plate distorts the field intensity emission of the cathode plate. (2) When the methane concentration changes from 3.5% to 13.5%, the number density of $H_{2}^{+}$ is relatively stable about 4×10¹⁵ m^-3, the number density of $O_{2}^{+}$ increases with increasing methane concentration when methane concentration is less than 8.5%. When the methane concentration is greater than or equal to 8.5%, the O₂ collision ionization in the mixed gas reaches saturation and does not increase with the increase of methane concentration. (3) The change of electrode distance affects the electric field intensity between electrodes and the discharge mechanism.

Key words： Explosive environment needle plate electrode hydrodynamic method micro gap discharge

Received: 08 April 2022

PACS:	O461
	TM863

	Service

	E-mail this article
	Add to my bookshelf
	Add to citation manager
	E-mail Alert
	RSS
	Articles by authors
	Wang Dangshu
	Deng Xuan
	Liu Shulin
	Yi Jia'an
	Wang Xinxia

Cite this article:

Wang Dangshu,Deng Xuan,Liu Shulin等. Microgap Discharge Characteristics of Methane/Air under the Needle Plate Electrode[J]. Transactions of China Electrotechnical Society, 2023, 38(13): 3388-3399.

URL:

https://dgjsxb.ces-transaction.com/EN/10.19595/j.cnki.1000-6753.tces.220560 OR https://dgjsxb.ces-transaction.com/EN/Y2023/V38/I13/3388

[1] 南阳防爆电气研究所. 防爆电气标准汇编第二分册: GB 3846—2010[S]. 2011.
[2] Uber C, Hilbert M, Felgner A, et al.Electrical discharges caused by opening contacts in an ignitable atmosphere-part I: analysis of electrical parameters at ignition limits[J]. Journal of Loss Prevention in the Process Industries, 2019, 61: 114-121.
[3] 刘建华. 爆炸性气体环境下本质安全电路放电理论及非爆炸评价方法的研究[D]. 徐州: 中国矿业大学, 2008.
[4] 王玉婷, 刘树林, 马一博, 等. 简单电容电路最小点燃电压曲线的数值化研究[J]. 电工技术学报, 2014, 29(增刊1): 345-350.
Wang Yuting, Liu Shulin, Ma Yibo, et al.Research on digitization of the minimum ignition voltage curve of simple capacitive circuit[J]. Transactions of China Electrotechnical Society, 2014, 29(S1): 345-350.
[5] 刘树林, 崔强, 李勇. Buck变换器的输出短路火花放电能量及输出本质安全判据[J]. 物理学报, 2013, 62(16): 168401.
Liu Shulin, Cui Qiang, Li Yong.Output short-circuit spark discharging energy and output intrinsic safety criterion of Buck converters[J]. Acta Physica Sinica, 2013, 62(16): 168401.
[6] 孟庆海, 田媛. 本质安全电路模拟储能元件潜在危险性分析及其本质安全判据[J]. 电工技术学报, 2022, 37(3): 676-685.
Meng Qinghai, Tian Yuan.Analysis of potential hazards of analog energy storage components in the intrinsic safety circuits and their intrinsic safety criteria[J]. Transactions of China Electrotechnical Society, 2022, 37(3): 676-685.
[7] 成永红, 孟国栋, 董承业. 微纳尺度电气击穿特性和放电规律研究综述[J]. 电工技术学报, 2017, 32(2): 13-23.
Cheng Yonghong, Meng Guodong, Dong Chengye.Review on the breakdown characteristics and discharge behaviors at the micro & nano scale[J]. Transactions of China Electrotechnical Society, 2017, 32(2): 13-23.
[8] 柴钰, 张妮, 刘杰, 等. 微尺度下N₂-O₂电晕放电的动态特性二维仿真[J]. 物理学报, 2020, 69(16): 183-192.
Chai Yu, Zhang Ni, Liu Jie, et al.Two-dimensional simulation of dynamic characteristics of N₂-O₂ corona discharge at micro scale[J]. Acta Physica Sinica, 2020, 69(16): 183-192.
[9] 王党树, 古东明, 栾哲哲, 等. 基于PIC/MCC法爆炸性气体环境下的微尺度放电特性[J]. 高电压技术, 2021, 47(3): 805-815.
Wang Dangshu, Gu Dongming, Luan Zhezhe, et al.Micro-scale discharge characteristics in explosive gas environment based on PIC/MCC method[J]. High Voltage Engineering, 2021, 47(3): 805-815.
[10] 廖瑞金, 刘康淋, 伍飞飞, 等. 棒-板电极直流负电晕放电过程中重粒子特性的仿真研究[J]. 高电压技术, 2014, 40(4): 965-971.
Liao Ruijin, Liu Kanglin, Wu Feifei, et al.Simulative study on characteristic of heavy particles in negative bar-plate DC corona discharge[J]. High Voltage Engineering, 2014, 40(4): 965-971.
[11] 何彦良, 丁未, 孙安邦, 等. 电场不均匀系数对SF₆/N₂混合气体负直流电晕电流脉冲特性的影响[J]. 电工技术学报, 2021, 36(15): 3124-3134.
He Yanliang, Ding Wei, Sun Anbang, et al.Effect of electric field non-uniformity coefficient on current pulse characteristics of negative DC corona in SF₆/N₂ gas mixtures[J]. Transactions of China Electrotechnical Society, 2021, 36(15): 3124-3134.
[12] Levko D, Raja L L.Fluid versus global model approach for the modeling of active species production by streamer discharge[J]. Plasma Sources Science and Technology, 2017, 26(3): 035003.
[13] 王伟, 杨悦民, 雷肖, 等. 基于有限元分析的大容量叠装电抗器温度场研究[J]. 高压电器, 2022, 58(8): 267-274.
Wang Wei, Yang Yuemin, Lei Xiao, et al.Research on temperature field of large capacity stacked reactor based on finite element analysis[J]. High Voltage Apparatus, 2022, 58(8): 267-274.
[14] 古海良, 周继贺, 蒋文明, 等. 低压预制母线温升特性的建模仿真研究[J]. 高压电器, 2022, 58(7): 214-222.
Gu Hailiang, Zhou Jihe, Jiang Wenming, et al.Modeling and simulation study on temperature rise of low-voltage prefabricated busbar[J]. High Voltage Apparatus, 2022, 58(7): 214-222.
[15] Herrebout D, Bogaerts A, Yan M, et al.One-dimensional fluid model for an rf methane plasma of interest in deposition of diamond-like carbon layers[J]. Journal of Applied Physics, 2001, 90(2): 570-579.
[16] Ivanov V, Proshina O, Rakhimova T, et al.Comparison of a one-dimensional particle-in-cell-Monte Carlo model and a one-dimensional fluid model for a CH₄/H₂ capacitively coupled radio frequency discharge[J]. Journal of Applied Physics, 2002, 91(10): 6296-6302.
[17] 柴钰, 弓丽萍, 张晶园, 等. 微纳电离式矿井甲烷传感器安全放电及敏感机理仿真[J]. 电工技术学报, 2019, 34(23): 4870-4879.
Chai Yu, Gong Liping, Zhang Jingyuan, et al.Simulation of safe discharge and sensitive mechanism of micro-nano ionized mine methane sensor[J]. Transactions of China Electrotechnical Society, 2019, 34(23): 4870-4879.
[18] 赵曰峰, 王超, 王伟宗, 等. 大气压甲烷针-板放电等离子体中粒子密度和反应路径的数值模拟[J]. 物理学报, 2018, 67(8): 085202.
Zhao Yuefeng, Wang Chao, Wang Weizong, et al.Numerical simulation on particle density and reaction pathways in methane needle-plane discharge plasma at atmospheric pressure[J]. Acta Physica Sinica, 2018, 67(8): 085202.
[19] M Torres J, Dhariwal R S. Electric field breakdown at micrometre separations in air and vacuum[J]. Microsystem Technologies, 1999, 6(1): 6-10.
[20] 孟国栋, 折俊艺, 应琪, 等. 微米尺度气体击穿的数值模拟研究进展[J]. 电工技术学报, 2022, 37(15): 3857-3875.
Meng Guodong, She Junyi, Ying Qi, et al.Research progress on numerical simulation of gas breakdown at microscale[J]. Transactions of China Electrotechnical Society, 2022, 37(15): 3857-3875.
[21] Go D B, Venkattraman A.Microscale gas breakdown: ion-enhanced field emission and the modified Paschen’s curve[J]. Journal of Physics D: Applied Physics, 2014, 47(50): 503001.
[22] Chen C H, Yeh J A, Wang P J.Electrical breakdown phenomena for devices with micron separations[J]. Journal of Micromechanics and Microengineering, 2006, 16(7): 1366-1373.
[23] Georghiou G E, Papadakis A P, Morrow R, et al.Numerical modelling of atmospheric pressure gas discharges leading to plasma production[J]. Journal of Physics D: Applied Physics, 2005, 38(20): R303-R328.
[24] 伍飞飞, 廖瑞金, 杨丽君, 等. 棒—板电极直流负电晕放电特里切尔脉冲的微观过程分析[J]. 物理学报, 2013, 62(11): 115201.
Wu Feifei, Liao Ruijin, Yang Lijun, et al.Numerical simulation of Trichel pulse characteristics in bar-plate DC negative corona discharge[J]. Acta Physica Sinica, 2013, 62(11): 115201.
[25] Wang Qiao, Ning Wenjun, Dai Dong, et al.Characteristics and mechanisms of transition from filament to homogeneous glow in atmospheric helium dielectric barrier discharges under variation of the applied voltage amplitude[J]. Journal of Physics D: Applied Physics, 2019, 52(20): 205201.
[26] Lazarou C, Belmonte T, Chiper A S, et al.Numerical modelling of the effect of dry air traces in a helium parallel plate dielectric barrier discharge[J]. Plasma Sources Science and Technology, 2016, 25(5): 055023.
[27] 刘学悫. 阴极电子学[M]. 北京: 科学出版社, 1980.
[28] Ramses, Snoeckx, . Influence of N₂ concentration in a CH₄/N₂ dielectric barrier discharge used for CH₄ conversion into H₂[J]. International Journal of Hydrogen Energy, 2013, 38(36): 16098-16120.
[29] (美)伯纳德·刘易斯(Bernard Lewis), (美)京特·冯·埃尔贝(Guenther von Elbe)著. 燃气燃烧与瓦斯爆炸[M]. 王方, 译. 北京: 中国建筑工业出版社, 2010.
[30] Sekimoto K, Takayama M.Negative ion formation and evolution in atmospheric pressure corona discharges between point-to-plane electrodes with arbitrary needle angle[J]. The European Physical Journal D, 2010, 60(3): 589-599.
[31] Forbes R G, Deane J H B. Reformulation of the standard theory of Fowler-Nordheim tunnelling and cold field electron emission[J]. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2007, 463(2087): 2907-2927.
[32] Descoeudres A, Levinsen Y, Calatroni S, et al.Investigation of the DC vacuum breakdown mechanism[J]. Physical Review Special Topics - Accelerators and Beams, 2009, 12(9): 092001.
[33] 徐翱, 金大志, 王亚军, 等. 场致发射影响微间隙气体放电形成的模拟[J]. 高电压技术, 2020, 46(2): 715-722.
Xu Ao, Jin Dazhi, Wang Yajun, et al.Simulation on influence of field emission to the gas discharge in micro-scale gaps[J]. High Voltage Engineering, 2020, 46(2): 715-722.
[34] Sekimoto K, Takayama M.Negative ion formation and evolution in atmospheric pressure corona discharges between point-to-plane electrodes with arbitrary needle angle[J]. The European Physical Journal D, 2010, 60(3): 589-599.