-
Inductively coupled plasma (ICP) generators involve complex interactions between electromagnetic, thermal, and chemical processes, which makes direct diagnostics difficult. To clarify these coupling mechanisms, a two-dimensional axisymmetric model of an argon ICP torch operating at kilopascal pressure is developed using COMSOL Multiphysics under local thermodynamic equilibrium (LTE) and non-equilibrium (NLTE) assumptions. A two-dimensional axisymmetric magnetohydrodynamic (MHD) model is established, which combines electromagnetic induction, convective-radiative heat transfer, and a seven-reaction argon plasma chemistry mechanism. The LTE model assumes that the temperature of all species is uniform, while the NLTE model independently solves for the electron temperature (Te) and gas temperature (Tg), thereby accounting for incomplete energy exchange between electrons and heavy particles. At a discharge power of 1000 W and a working pressure of 10 kPa, the LTE model predicts a peak temperature of approximately 8200 K, concentrated around the induction coils. In contrast, the NLTE model yields a maximum gas temperature of about 5990 K, with the hot zone shifted downstream. The NLTE model reveals a clear two-temperature structure: Te peaks near the coil wall (~0.93 eV), while Tg reaches its maximum downstream, indicating a pronounced thermal non-equilibrium state where electrons are preferentially heated by the induced field. The calculated skin depth (~11.3 mm) coincides with the region of strongest electromagnetic energy deposition. Species analysis shows that the plasma core is dominated by ground-state argon (Ar) (>99%), while excited argon (Ar*) and argon ions (Ar+) increase notably near the coil region, confirming that excitation and ionization processes are localized within the skin layer. Furthermore, comparison between the 5 kPa and 10 kPa cases shows that as pressure decreases, the difference between Te and Tg increases, indicating enhanced thermal non-equilibrium due to reduced collisional coupling. Overall, the results highlight that LTE and NLTE assumptions lead to markedly different predictions of temperature and energy coupling at kilopascal pressures. The NLTE model more realistically captures delayed energy transfer and spatial temperature decoupling, offering new insights into the electromagnetic-thermal-flow interactions of ICP discharges and providing a modeling reference for designing ICP-based high-enthalpy plasma wind tunnel and realizing related aerospace applications.
-
图 1 感应耦合等离子体发生器结构示意图
Figure 1. Schematic diagram of the structure of the inductively coupled plasma generator.
图 2 感应耦合等离子体发生器网格划分
Figure 2. Meshing of inductively coupled plasma generator.
图 3 1000 W非平衡态与平衡态感应耦合等离子体放电温度云图 (a) 非平衡态; (b) 平衡态
Figure 3. Temperature cloud diagram of 1000 W non-equilibrium and equilibrium inductively coupled plasma discharge: (a) Non-equilibrium state; (b) equilibrium state.
图 4 平衡模型和非平衡模型下中轴线上温度分布变化
Figure 4. Variation of temperature distribution on the central axis under the equilibrium model and the unbalanced model.
图 5 氩气感应耦合等离子体放电过程的气体温度分布 (a) 2 ms; (b) 4 ms; (c) 6 ms; (d) 8 ms; (e) 9 ms; (f) 10 ms
Figure 5. The gas temperature distribution in the argon gas induction coupled plasma discharge process: (a) 2 ms; (b) 4 ms; (c) 6 ms; (d) 8 ms; (e) 9 ms; (f) 10 ms.
图 6 放电初期(2 ms)1000 W放电管内磁场分布
Figure 6. Magnetic field distribution in the 1000 W discharge tube at the initial stage of discharge (2 ms).
图 7 1000 W不同时刻中心轴线气体温度分布
Figure 7. The gas temperature distribution along the central axis at different times of 1000 W.
图 8 稳态阶段1000 W放电管内分布云图 (a) 电子温度; (b) 气体温度
Figure 8. Distribution cloud diagram of 1000 W discharge tube in the steady-state stage: (a) Electron temperature; (b) gas temperature.
图 9 稳态阶段1000 W放电管内气体速度分布云图
Figure 9. Cloud diagram of gas velocity distribution in a 1000 W discharge tube during the steady-state stage.
图 10 稳态阶段1000 W放电管内中轴线上粒子摩尔分数分布
Figure 10. The particle mole fraction distribution on the central axis of the 1000 W discharge tube during the steady-state stage.
图 11 稳态阶段1000 W放电管内z = 91.5 mm截线(线圈1, 2中间位置)粒子摩尔分数分布
Figure 11. The particle mole fraction distribution of z = 91.5 mm cross-sectional wire (the middle position between coils 1 and 2) in the 1000 W discharge tube during the steady-state stage.
图 12 不同压力下中心线上气体温度和电子温度
Figure 12. The gas temperature and electron temperature on the center line under different pressures.
表 1 氩气化学反应
Table 1. Argon chemical reaction.
反应 反应方程 反应类型 反应速率系数 Δε/eV 1 e+Ar→e+Ar 弹性碰撞 kel / 2 e+Ar→e+Ar* 激发 kex 11.56 3 e+Ar*→e+Ar 激发 ksc –11.56 4 e+Ar→2e+Ar+ 电离 ki 15.6 5 e+Ar*→2e+Ar+ 电离 ksi 4.14 6 Ar*+Ar*→
e+Ar+Ar+潘宁电离 kmp — 7 Ar+Ar*→Ar+Ar 亚稳猝灭 k2 p — 
DownLoad: CSV
-
[1] 詹志华, 王春华, 周秋娇, 刘成周, 赵鹏 2022 电工技术学报 37 2725
Zhan Z H, Wang C H, Zhou Q J, Liu C Z, Zhao P 2022 Trans. China Electrotech. Soc. 37 2725
[2] Bottin A, Carbonaro M, Haegen V V, Paris S 1999 ESA Publications Division 462 553
[3] Panerai F, Chazot O 2012 Mater. Chem. Phys. 134 597
Google Scholar
[4] Ito T, Ishida K, Mizuno M, Sumi T, Matsuzaki T, Nagai J, Murata H 2005 43rd AIAA Aerospace Science Meeting and Exhibit Reno, Nevada, January 10−13, 2005 pp10−13
[5] 林烈, 吴彬, 吴承康 2001 空气动力学学报 19 407
Lin L, Wu B, Wu C K 2001 Acta Aerodyn. Sin. 19 407
[6] 刘丽萍, 王国林, 王一光, 张军, 罗磊 2017 航空学报 39 421696
Liu L P, Wang G L, Wang Y G, Zhang J, Luo L 2017 Acta Aeronaut. Astronaut. Sin. 39 421696
[7] Luo L, Wang Y, Liu L, Duan L, Wang G, Lu Y 2016 Carbon 103 73
Google Scholar
[8] 张晓宁, 李和平, Murphy A B, 夏维东 2013 高电压技术 39 1640
Zhang X N, Li H P, Murphy A B, Xia W D 2013 High Volt. Eng. 39 1640
[9] Fujino T, Ito S, Okuno Y 2021 IEEE Trans. Plasma Sci. 49 2954
Google Scholar
[10] Al-Mamun S A, Tanaka Y, Uesugi Y 2010 Plasma Chem. Plasma Process. 30 141
Google Scholar
[11] Fujita K, Suzuki T, Mizuno M, Fujii K 2009 J. Thermophys. Heat Transf. 23 840
Google Scholar
[12] Tanaka Y, Sakuta T 2002 J. Phys. D: Appl. Phys. 35 2149
Google Scholar
[13] Degrez G, Abeele D V, Barbante P, Bottin B 2004 Int. J. Numer. Methods Heat Fluid Flow 14 538
Google Scholar
[14] 李日正, 倪国华, 孙红梅, 王城 2024 真空科学与技术学报 44 819
Li R Z, Ni G H, Sun H M, Wang C 2024 Chin. J. Vac. Sci. Technol. 44 819
[15] Liu Y, Xia G 2025 6th International Conference on Mechatronics Technology and Intelligent Manufacturing Nanjing, China, April 11−13, 2025 pp226−229
[16] 张雨涵, 赵欣茜, 梁英爽, 郭媛媛 2024 73 135201
Google Scholar
Yu H Z, Xin Q Z, Ying S L, Yuan Y G 2024 Acta Phys. Sin. 73 135201
Google Scholar
[17] Stewart R A, Vitello P, Graves D B 1994 J. Vac. Sci. Technol. B 12 478
Google Scholar
[18] Lei F, Li X, Liu Y, Liu D, Yang M, Yu Y 2018 AIP Adv. 8 015003
Google Scholar
[19] Punjabi S B, Joshi N K, Mangalvedekar H A, Lande B K, Das A K, Kothari D C 2012 Phys. Plasmas 19 012108
Google Scholar
[20] 朱海龙, 童洪辉, 杨发展, 程昌明, 叶高英 2013 高电压技术 39 1621
Zhu H L, Tong H H, Yang F Z, Cheng C M, Ye G Y 2013 High Volt. Eng. 39 1621
[21] 余德平, 吴杰, 涂军, 张仕杨, 辛强, 万勇建 2020 哈尔滨工业大学学报 52 82
Yu D P, Wu J, Tu J, Zhang S Y, Xin Q, Wan Y J 2020 J. Harbin Inst. Technol. 52 82
[22] Fujita K, Suzuki T, Ozawa T 2011 27th International Symposium on Rarefied Gas Dynamics Pacific Grove, California, USA, July 10−15, 2011 pp407−412
[23] 徐姿, 龚学余, 杜丹, 陈文波 2018 低温 40 36
Xu Z, Gong X Y, Du D, Chen W B 2018 J. Low Temperat. Phys. 40 36
[24] 2025-08-25 [荣命哲http://plasma-data.net/index
[2025-08-25
[25] Yu M, Yamada K, Takahashi Y, Liu K, Zhao T 2016 Phys. Plasmas 23 123523
Google Scholar
[26] Satoshi M, Kazuhiko Y, Takashi A 2015 JAXA Special Publication JAXA-SP-14-010 17−22
DownLoad:
Metrics
- Abstract views: 93
- PDF Downloads: 9
- Cited By: 0
