Article
Physics, Applied
Yuqing Dong, Jiacheng Zhang, Peng Zhang, Hengxi Tian, Deping Yu
Summary: This paper investigates the regulation and optimization of the jet morphology in fluorine-containing plasma. The results show that a moderate addition of CF4 and O2 can promote the ionization process, while excessive addition inhibits the production of active radicals and limits the jet size. Optimizing the proportions of CF4 and O2 as well as the applied power greatly improves the jet morphology.
PLASMA PROCESSES AND POLYMERS
(2022)
Article
Engineering, Civil
Monika Szada-Borzyszkowska, Wojciech Kacalak, Kamil Banaszek, Przemyslaw J. Borkowski, Wieslaw Szada-Borzyszkowski
Summary: In this article, the results of processing aerated concrete using pulsating water jet are presented. Discontinuous water flow through the nozzle was achieved using a self-excited head. The efficiency of machining for continuous and pulsating water jet was measured by assessing the erosive effects on processed materials. Pulsations were confirmed by measuring the water jet thrust forces acting on a piezoelectric sensor. It was concluded that pulsating water jet had greater processing effectiveness under certain circumstances compared to continuous flow, particularly during the surface processing of concrete blocks.
ARCHIVES OF CIVIL AND MECHANICAL ENGINEERING
(2023)
Article
Engineering, Electrical & Electronic
Cheng Wang, Xiaoen Chen, Jianping Chen, Guiling Wu
Summary: In this paper, a model for the 'Dual-output MZM (DOMZM)-filter-balanced PD (BPD)'-based microwave photonic link is built, where the filter's amplitude and phase responses are arbitrary. It is proven that this link can eliminate the residual even harmonics. Theoretical analysis is verified by simulation and experimental results. By using this structure, the SFDR limited by even harmonics can be improved and the sampling frequency range can be expanded for PADCs. The SFDR can be further improved by applying inverse cosine transform for calibrating the nonlinearity of the MZM, as the spectrum only contains odd harmonics.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Physics, Applied
Chaoxia Zhao, Xinxin Li, Dinesh K. K. Agrawal, Zhili Yan, Siyao Qi, Yao Liu, Tianbao Ma, Qian Chen, Yi Zhang, Ce Wang, Kama Huang
Summary: A microwave atmospheric pressure plasma jet (MW-APPJ) generator based on a substrate-integrated waveguide (SIW) resonator is proposed, which can achieve a thin, straight plasma needle with a length of 9 cm. It has a high microwave feeding efficiency of over 90% under a wide range of gas flow rates without the need for a microwave matching network. The plasma jet's morphology transitions from laminar to turbulent mode as the gas flow increases from 1 to 14 L/min. Additionally, the SIW-based plasma generator can effectively make the polyimide film super hydrophilic after a 5-min treatment.
PLASMA PROCESSES AND POLYMERS
(2023)
Article
Physics, Fluids & Plasmas
Sile Chen, Xinliu Ren, Zhaoquan Chen, Xiaojuan Xu, Tao Cheng, Ping LI, Guanjun Zhang, Xinpei Lu
Summary: This work aims to develop an atmospheric fluorocarbon plasma jet for surface modification of insulating materials. By using a coaxial transmission line resonator and microwave discharge with locally enhanced electric field, the gas temperature is reduced and the electron density is increased. The Ar/CF4 plasma jet is found to have the best performance, with strong discharge intensity and controllable gas temperature. It is considered as a promising source for surface fluorination of polymers.
PLASMA SCIENCE & TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Lev A. Yurovskiy, Irina Zotova, Naum S. Ginzburg, Michael N. Vilkov, Roman M. Rozental, Sergey Samsonov, Edward B. Abubakirov
Summary: Efficient amplification and recompression of sub-nanosecond microwave superradiant pulses, which underwent preliminary stretching and frequency chirping, can generate Ka-band sub-nanosecond pulses with peak power of about ten gigawatts. This technique is similar to Chirped Pulse Amplification (CPA) used in petawatt-class lasers.
IEEE ELECTRON DEVICE LETTERS
(2021)
Article
Engineering, Chemical
Wenjie Fu, Chaoyang Zhang, Xiaotong Guan, Xiaoyun Li, Yang Yan
Summary: An investigation of sterilization using a low-temperature microwave-generated atmospheric pressure plasma jet (MAPPJ) is presented. The study examined the effects of the plasma treatment on different bacteria and fungi, and found that the number of bacterial colonies was significantly reduced and almost eliminated after several minutes of treatment.
JOURNAL OF MICROWAVE POWER AND ELECTROMAGNETIC ENERGY
(2022)
Article
Physics, Fluids & Plasmas
S. N. Antipov, V. M. Chepelev, M. Kh. Gadzhiev, A. G. Abramov, A. V. Ugryumov
Summary: The investigation focused on the atmospheric-pressure cold plasma jet generated by the interelectrode microwave discharge in argon. A waveguide-type 2.45 GHz plasmatron with an external 6-rod electrode plasma torch was used as the source. High-speed shadowgraphy was employed to analyze the spatio-temporal structure of the plasma jet. The periodic plasma generation was studied through electric probe floating potential measurements with an oscilloscope.
PLASMA PHYSICS REPORTS
(2023)
Article
Thermodynamics
M. A. Pakhomov, V. Terekhov
Summary: A numerical investigation was conducted to study the influence of pulse shape on heat transfer in an impact pulsed gas-droplet jet. The results showed that heat transfer can either increase or be suppressed in the pulsating flow compared to the stationary flow. The distance between the pipe cut and the barrier plays a role in determining whether heat transfer increases or decreases.
JOURNAL OF ENGINEERING PHYSICS AND THERMOPHYSICS
(2022)
Article
Physics, Fluids & Plasmas
Jinming Li, Dmitrii V. Bogdanov, Anatoly A. Kudryavtsev, Evgeniy A. Bogdanov, Chengxun Yuan, Zhongxiang Zhou, Xiaoou Wang
Summary: This study investigates the influence of discharge current, gas pressure, and axial magnetic field on the spatial distributions of a dusty argon plasma in a dc glow discharge positive column. Results show that increasing current, pressure, or magnetic field enhances dust influence on particle distribution and plasma fluxes, leading to various outcomes like flattened radial density or even nonmonotonic distributions with ambipolar field reversal. Three different transition modes to nonmonotonic radial density profiles are reported depending on the parameter being changed.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2021)
Article
Physics, Fluids & Plasmas
Hailu Wang, Jingfeng Yao, Aleksandr M. Astafiev, Anatoly A. Kudryavtsev, Chengxun Yuan, Zhongxiang Zhou, He-Ping Li
Summary: This study addresses the influence of an extended plasma jet on the radiation pattern of a short-grounded antenna in the frequency range of 1-3 GHz. Numerical and theoretical methods were used to determine the radiation pattern, and consistent results were obtained. A novel microwave diagnostic method for atmospheric plasma jets was also proposed based on the findings.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2022)
Article
Physics, Fluids & Plasmas
Shubo Li, Zhe Ding, Kurban M. Rabadanov, Anatoly A. Kudryavtsev, Nazir A. Ashurbekov, Jingfeng Yao, Chengxun Yuan, Zhongxiang Zhou
Summary: The formation of a nonlocal electron distribution function (EDF) in an argon dusty plasma of a dc glow discharge has been studied. The spatial profile of charges and the ambipolar potential can greatly vary with changes in the density and distribution of dust particles. This leads to strong differences in the nonlocal EDF at different points of the tube radius, especially at high dust particle densities.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2022)
Article
Physics, Fluids & Plasmas
Chengxun Yuan, Yan Chai, Eugene A. Bogdanov, Anatoly A. Kudryavtsev
Summary: This study investigates the influence of electron-electron collisions on the formation of inverse electron distribution function (EDF) and absolute negative conductivity (ANC) in a nonlocal plasma of a direct current glow discharge. A numerical model was built using COMSOL Multiphysics software and it includes kinetic equations for electrons, drift-diffusion fluid balance equations for heavy particles, and a Poisson equation for the electric field. The results show that the increase in electron-electron collisions limits the possibility of reverse EDF and ANC in rare gas nonlocal plasmas with Ramsauer minimum cross section.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2022)
Article
Physics, Fluids & Plasmas
Chengxun Yuan, Yan Chai, Eugene A. Bogdanov, Anatoly A. Kudryavtsev
Summary: It is demonstrated that the phenomenon of absolute negative electron mobility (ANG) has a subtle effect when considering the local plasma-chemical balance, and the sign of the electron mobility depends on the contribution of electronegative impurities.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2022)
Article
Physics, Fluids & Plasmas
Jianfei Li, Jingfeng Yao, Chengxun Yuan, Ying Wang, Zhongxiang Zhou, Jingwen Zhang, Anatoly A. Kudryavtsev
Summary: The inverse-brush-electrodes (IBE) structure is designed to investigate the discharge mechanism driven by alternating current (ac). It increases the number of secondary electrons and reduces the breakdown voltage compared to plate electrodes. The breakdown mechanism of gas discharge driven by ac is analyzed, and the negative differential conductivity enhancement effect of the IBE structure in heavy noble gas plasmas is studied. The effect is attributed to the non-equilibrium electron energy distribution function (EEDF) caused by the generation of suprathermal electrons by the IBE structure.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2023)
Article
Physics, Fluids & Plasmas
N. A. Ashurbekov, M. Z. Zakaryaeva, K. M. Rabadanov, K. O. Iminov, M. B. Kurbangadzhieva, A. A. Kudryavtsev
Summary: This paper proposes a convenient method for calculating the electron energy distribution function (EEDF) in a gas-discharge plasma. The method is demonstrated by calculating the EEDF of a plasma column in a high-voltage nanosecond discharge in argon with an extended hollow cathode. The applicability of the method for calculating the EEDF in a pulsed discharge sustained by a 50 Hz pulse and gas pressure from 5 to 40 Torr is assessed.
PHYSICS OF PLASMAS
(2022)
Article
Physics, Fluids & Plasmas
Zijia Chu, Jingfeng Yao, Chengxun Yuan, Zhongxiang Zhou, Anatoly Kudryavtsev, Ying Wang, Xiaoou Wang
Summary: Laboratory plasmas, as highly nonlinear mediums, can exhibit various nonlinear phenomena. Hysteresis often occurs due to the coexistence of multiple attractors in nonlinear systems. In this study, a two-dimensional plasma fluid model is developed to investigate the hysteresis phenomenon in the nonlinear dynamical behaviors of low-pressure DC glow discharge. The results show that the selected initial discharge conditions significantly influence the exhibited nonlinear dynamical behaviors of the system.
PHYSICS OF PLASMAS
(2023)
Article
Physics, Fluids & Plasmas
Jingfeng Yao, Chai Yan, Chengxun Yuan, Eugene A. Bogdanov, Kurban Rabadanov, Zhijia Chu, Anatoly Kudryavtsev
Summary: This study presents self-consistent simulations of a glow discharge positive column in low-pressure nitrogen plasma. The electron energy distribution function (EEDF) was calculated by solving the nonlocal Boltzmann kinetic equation for electrons. The accuracy and applicability of the local and nonlocal approximations were examined. The results show that the nonlocal approximation is suitable at low nitrogen pressures, but a large intermediate region exists where the EEDF is nonlocal and requires solving the full kinetic equation. Therefore, the use of a local approximation in finding the EEDF should be carefully verified, especially at the periphery of the discharge volume where the self-consistent ambipolar field dominates.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Article
Optics
Jianfei Li, Jingfeng Yao, Ying Wang, Zhongxiang Zhou, Anatoly. A. A. Kudryavtsev, Zhihao Lan, Chengxun Yuan
Summary: Traditional methods focus on mitigating electron densities and impurities around the antenna to alleviate plasma blackout, while metamaterial-based electromagnetic methods have yet to be proven experimentally. We simulate the plasma blackout problem using laboratory plasma supported by gas discharge technology. Topological edge states (TESs) that are insensitive to weak impurities in the transport path are verified theoretically and experimentally, providing a new approach to the blackout communication problem and serving as a nascent experimental platform to investigate topological electromagnetic phenomena.
Article
Physics, Fluids & Plasmas
Mohamed M. Mandour, Sergey A. Astashkevich, Anatoly A. Kudryavtsev
Summary: Photoplasma in Na-Ar mixtures in a two-chamber cell was studied to generate an electromotive force (EMF) with a wide range of buffer gas pressure. The Voigt profile of the D1 and D2 resonance lines of Na was investigated by considering radiation transfer within the framework of the Biberman-Holstein approximation. The obtained EMF was found to change its sign with buffer gas pressure variation due to the peculiarities of charge transport in the cell.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2023)
Article
Physics, Fluids & Plasmas
Jingfeng Yao, Yan Chai, Chengxun Yuan, Eugene A. Bogdanov, Anatoly A. Kudryavtsev, Zhijia Chu, Ying Wang, Zhongxiang Zhou
Summary: This study analyzes the formation of the electron energy distribution function (EEDF) and phase flows of electrons in a positive column of a glow discharge in a model gas with strong vibrational excitation. It is found that the traditional local approximation for calculating the EEDF is only valid at medium gas pressures, and at lower gas pressures, the phase flow streamlines merge into a single line on the coordinate-energy phase plane. This merging is due to the combination of a strong electron sink at the vibrational excitation threshold and the deceleration of electrons in an ambipolar field.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Article
Computer Science, Information Systems
Shixin Zhao, Xingbao Lyu, Yangguo Liu, Chengxun Yuan, Svetlana Avtaeva, Anatoly Kudryavtsev, Xiaoxue Li, Jingfeng Yao, Ying Wang, Zhongxiang Zhou
Summary: The characteristics of post-cathode plasma in a self-made DC short glow-discharge plasma generator with grid electrodes were measured using optical emission spectroscopy. The discharge operated in an abnormal glow discharge mode at a voltage of 250-400 V, a helium pressure of 3-15 Torr, and a discharge gap of 3 mm. The results showed that the intensity distribution of helium atom spectral lines differed between the post-cathode and post-anode spaces, and the temperature of electron excitation in the post-cathode plasma reached a peak of 1500-3000K at a distance of 5-6 mm from the grid cathode.
Article
Physics, Fluids & Plasmas
Zijia Chu, Jingfeng Yao, Chengxun Yuan, Zhongxiang Zhou, Anatoly Kudryavtsev, Xiaoou Wang, Ying Wang
Summary: This study investigates chaos phenomenon in the subnormal glow region of an undriven direct current glow discharge through the establishment of a two-dimensional plasma fluid model and coupling it with a circuit model. Various bifurcation processes are observed in the oscillation region, and the impact of control parameter on the spatiotemporal distribution of plasma parameters is examined. Additionally, the existence of periodic windows and intermittent chaos near the period-3 window is discovered.
Article
Computer Science, Information Systems
Xingbao Lyu, Chengxun Yuan, Svetlana Avtaeva, Anatoly Kudryavtsev, Jingfeng Yao, Yangguo Liu, Zhongxiang Zhou, Xiaoou Wang
Summary: This paper presents a new composite grid electrode structure, GA-CC, for generating plasma in atmospheric conditions. Compared to the ordinary grid anode-cathode plate (GA-CP) structure, the GA-CC structure has a lower breakdown voltage and is slightly shifted to the right on the Pd-axis. A notable advantage of the GA-CC structure is that it requires a lower voltage to generate the same current. Moreover, the plasma generated by the GA-CC structure selectively enhances electromagnetic wave attenuation within the frequency range of 9-12 GHz.
