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An open-end high-power microwave-induced fracturing system for hard rock 被引量:2
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作者 Xia-Ting Feng Jiuyu Zhang +4 位作者 Feng Lin Chengxiang Yang Shiping Li Tianyang Tong Xiangxin Su 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第12期3163-3172,共10页
Microwave pre-treatment is considered as a promising technique for alleviating cutter wear. This paper introduces a high-power microwave-induced fracturing system for hard rock. The test system consists of a high-powe... Microwave pre-treatment is considered as a promising technique for alleviating cutter wear. This paper introduces a high-power microwave-induced fracturing system for hard rock. The test system consists of a high-power microwave subsystem (100 kW), a true triaxial testing machine, a dynamic monitoring subsystem, and an electromagnetic shielding subsystem. It can realize rapid microwave-induced fracturing, intelligent tuning of impedance, dynamic feedback under strong microwave fields, and active control of microwave parameters by addressing the following issues: the instability and insecurity of the system, the discharge breakdown between coaxial lines during high-power microwave output, and a lack of feedback of rock-microwave response. In this study, microwave-induced surface and borehole fracturing tests under true triaxial stress were carried out. Experimental comparisons imply that high-power microwave irradiation can reduce the fracturing time of hard rock and that the fracture range (160 mm) of a 915-MHz microwave source is about three times that of 2.45 GHz. After microwave-induced borehole fracturing, many tensile cracks occur on the rock surface and in the borehole: the maximum reduction of the P-wave velocity is 12.8%. The test results show that a high-power microwave source of 915 MHz is more conducive to assisting mechanical rock breaking and destressing. The system can promote the development of microwave-assisted rock breaking equipment. 展开更多
关键词 Hard rock engineering high-power microwave microwave intelligent fracturing Dynamic feedback True triaxial stress
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Damage effects and mechanism of the silicon NPN monolithic composite transistor induced by high-power microwaves 被引量:4
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作者 Hui Li Chang-Chun Chai +2 位作者 Yu-Qian Liu Han Wu in-Tang Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期633-639,共7页
A two-dimensional model of the silicon NPN monolithic composite transistor is established for the first time by utilizing the semiconductor device simulator, Sentaurus-TCAD. By analyzing the internal distributions of ... A two-dimensional model of the silicon NPN monolithic composite transistor is established for the first time by utilizing the semiconductor device simulator, Sentaurus-TCAD. By analyzing the internal distributions of electric field, current density, and temperature of the device, a detailed investigation on the damage process and mechanism induced by high-power microwaves (HPM) is performed. The results indicate that the temperature elevation occurs in the negative half-period and the temperature drop process is in the positive half-period under the HPM injection from the output port. The damage point is located near the edge of the base-emitter junction of T2, while with the input injection it exists between the base and the emitter of T2. Comparing these two kinds of injection, the input injection is more likely to damage the device than the output injection. The dependences of the damage energy threshold and the damage power threshold causing the device failure on the pulse-width are obtained, and the formulas obtained have the same form as the experimental equations, which demonstrates that more power is required to destroy the device if the pulse-width is shorter. Furthermore, the simulation result in this paper has a good coincidence with the experimental result. 展开更多
关键词 monolithic composite transistor high-power microwaves damage effects pulse-width effects
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Research progresses on Cherenkov and transit-time high-power microwave sources at NUDT 被引量:9
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作者 Jiande Zhang Xingjun Ge +7 位作者 Jun Zhang Juntao He Yuwei Fan Zhiqiang Li Zhenxing Jin Liang Gao Junpu Ling Zumin Qi 《Matter and Radiation at Extremes》 SCIE EI CAS 2016年第3期163-178,共16页
Research progresses on Cherenkov and transit-time high-power microwave(HPM)sources in National University of Defense Technology(NUDT)of China are presented.The research issues are focused on the following aspects.The ... Research progresses on Cherenkov and transit-time high-power microwave(HPM)sources in National University of Defense Technology(NUDT)of China are presented.The research issues are focused on the following aspects.The pulse-shortening phenomenon in O-type Cerenkov HPM devices is suppressed.The compact coaxial relativistic backward-wave oscillators(RBWOs)at low bands are developed.The power efficiency in M-Type HPM tubes without guiding magnetic field increased.The power capacities and power efficiencies in the triaxial klystron amplifier(TKA)and relativistic transit-time oscillator(TTO)at higher frequencies increased.In experiments,some exciting results were obtained.The X-band source generated 2 GW microwave power with a pulse duration of 110 ns in 30 Hz repetition mode.Both L-and P-band compact RBWOs generated over 2 GW microwave power with a power efficiency of over 30%.There is approximately a 75% decline of the volume compared with that of conventional RBWO under the same power capacity conditions.A 1.755 GHz MILO produced 3.1 GW microwave power with power efficiency of 10.4%.A 9.37 GHz TKA produced the 240 MW microwave power with the gain of 34 dB.A 14.3 GHz TTO produced 1 GW microwave power with power efficiency of 20%. 展开更多
关键词 high-power microwave(HPM) Long-pulse O-type Cerenkov source Magnetically insulated line oscillator(MILO) Coaxial relativistic backwardwave oscillator(RBWO) Triaxial klystron amplifier(TKA) Transit-time oscillator(TTO)
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Investigation on latch-up susceptibility induced by high-power microwave in complementary metal–oxide–semiconductor inverter 被引量:4
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作者 Yu-Hang Zhang Chang-Chun Chai +4 位作者 Xin-Hai Yu Yin-Tang Yang Yang Liu Qing-Yang Fan Chun-Lei Shi 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期492-498,共7页
The latch-up effect induced by high-power microwave(HPM) in complementary metal–oxide–semiconductor(CMOS) inverter is investigated in simulation and theory in this paper. The physical mechanisms of excess carrie... The latch-up effect induced by high-power microwave(HPM) in complementary metal–oxide–semiconductor(CMOS) inverter is investigated in simulation and theory in this paper. The physical mechanisms of excess carrier injection and HPM-induced latch-up are proposed. Analysis on upset characteristic under pulsed wave reveals increasing susceptibility under shorter-width pulsed wave which satisfies experimental data, and the dependence of upset threshold on pulse repetitive frequency(PRF) is believed to be due to the accumulation of excess carriers. Moreover, the trend that HPMinduced latch-up is more likely to happen in shallow-well device is proposed.Finally, the process of self-recovery which is ever-reported in experiment with its correlation with supply voltage and power level is elaborated, and the conclusions are consistent with reported experimental results. 展开更多
关键词 high-power microwave latch-up repetitive pulse frequency supply voltage dependence
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High-power microwave propagation properties in the argon plasma array
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作者 Yang LIU Jiaming SHI +3 位作者 Li CHENG Jiachun WANG Zhongcai YUAN Zongsheng CHEN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第1期44-51,共8页
The argon plasma induced by the L-/C-band high-power microwave(HPM) is investigated theoretically and experimentally. Influences of the microwave power, pulse width, polarization and the plasma electron density on the... The argon plasma induced by the L-/C-band high-power microwave(HPM) is investigated theoretically and experimentally. Influences of the microwave power, pulse width, polarization and the plasma electron density on the protection performance of the plasma array against HPM are studied. The results show that the effect of HPM is caused by energy accumulation, with the gas breakdown emerging only after a short time. The attenuation of the wave by the plasma array with the tubes off can reach approximately 23 dB at 1.3 GHz. It can also be obtained that the protection performance of the plasma array against the TE wave is better than that against the TM one. The plasma array shows better protection performance in the L-band than in the C-band. In addition,the attenuation of 5.6 GHz HPM can reach 30 dB when the tubes are turned on in the experiment.The research shows that the plasma array has protection ability against HPM. 展开更多
关键词 high-power microwave PLASMA ARRAY ARGON BREAKDOWN protection performance experiment
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Analysis of High-Power Microwave Propagation in a Magnetized Plasma Filled Waveguide
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作者 傅文杰 鄢扬 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第10期974-978,共5页
Plasma filling can dramatically improve the performance of high power microwave devices. The characteristics of high-power microwave propagation along plasma filled waveguides in an axial magnetic field are analyzed i... Plasma filling can dramatically improve the performance of high power microwave devices. The characteristics of high-power microwave propagation along plasma filled waveguides in an axial magnetic field are analyzed in this paper, and the ponderomotive force effect of high power microwave is taken into consideration. Theoretical analysis and preliminary numerical calculations are performed. The analyses show that the ponderomotive effect would change the plasma density, distribution of microwave field intensity, and dispersion of wave propagation. The higher the microwave power, the stronger the ponderomotive effect. In different magnetic fields, the ponderomotive effect is different. 展开更多
关键词 magnetic plasma high-power microwave plasma filled waveguide pondero-motive effect
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Short-pulse high-power microwave breakdown at high pressures
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作者 赵朋程 廖成 冯菊 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第2期282-286,共5页
The fluid model is proposed to investigate the gas breakdown driven by a short-pulse(such as a Gaussian pulse) highpower microwave at high pressures.However,the fluid model requires specification of the electron ene... The fluid model is proposed to investigate the gas breakdown driven by a short-pulse(such as a Gaussian pulse) highpower microwave at high pressures.However,the fluid model requires specification of the electron energy distribution function(EEDF);the common assumption of a Maxwellian EEDF can result in the inaccurate breakdown prediction when the electrons are not in equilibrium.We confirm that the influence of the incident pulse shape on the EEDF is tiny at high pressures by using the particle-in-cell Monte Carlo collision(PIC-MCC) model.As a result,the EEDF for a rectangular microwave pulse directly derived from the Boltzmann equation solver Bolsig+ is introduced into the fluid model for predicting the breakdown threshold of the non-rectangular pulse over a wide range of pressures,and the obtained results are very well matched with those of the PIC-MCC simulations.The time evolution of a non-rectangular pulse breakdown in gas,obtained by the fluid model with the EEDF from Bolsig+,is presented and analyzed at different pressures.In addition,the effect of the incident pulse shape on the gas breakdown is discussed. 展开更多
关键词 fluid model electron energy distribution function gas breakdown short-pulse high-power microwave
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Design of High-power Microwave Waveguide Divider
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作者 凌晨 匡光力 刘甫坤 《Plasma Science and Technology》 SCIE EI CAS CSCD 2001年第5期985-990,共6页
A new LHW antenna will be used in LHCD system on tokanak HT-7U, where a high-power microwave waveguide power divider is a key device. This paper presents the power divider structure whose coupling element is in the co... A new LHW antenna will be used in LHCD system on tokanak HT-7U, where a high-power microwave waveguide power divider is a key device. This paper presents the power divider structure whose coupling element is in the common narrow wall between two identical waveguides, a certain of which is completely excavated. Green's Function Method is used to analyze the electric field distributions of the structure, and consequently the graphs between the scattering matrix and the geometrical dimensions are given. The graphs can be straightly applied to the process of the power divider. 展开更多
关键词 Design of high-power microwave Waveguide Divider
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Nonlinear Properties of an Inhomogeneous Diode Structure in a Strong Microwave Field
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作者 Sanobar Reymbaeva Gulmurza Abdurakhmanov Aleksandra Orel 《World Journal of Condensed Matter Physics》 CAS 2023年第1期1-13,共13页
Results of experimental investigation of detection (rectification) of high power X-band microwave signal in diodes of various design (semiconductor p-n-junction, point-contact, Schottky, Metal-Isolator-Metal—MIM) are... Results of experimental investigation of detection (rectification) of high power X-band microwave signal in diodes of various design (semiconductor p-n-junction, point-contact, Schottky, Metal-Isolator-Metal—MIM) are reported. The maximum of the detected direct voltage V vs. power P of microwave signal and subsequent polarity reversal, previously found in MIM diodes in the optical and microwave bands, have found to be characteristic of all investigated diodes as well. After the reversal of polarity, this dependence comes linear, and the sign of the voltage corresponds to thermoEMF. In some diodes, the hysteresis on V(P) was observed. All 5 types of V(P) of MIM diodes (have made from different pairs of metals), reported earlier, were reproduced on same p-n-junction diode by variable external DC bias. These results joined with abnormal frequency cutoff forced to suggest that there is an unknown mechanism for direct flow of charge carriers (and for generate direct current) in the high-frequency electrical field, which differs from the conventional rectification. 展开更多
关键词 Quadratic Detection p-n-Junction Point Contact Schottky Barrier high-power microwave Signal Polarity Reversal ThermoEMF HYSTERESIS
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Recent progress of parameter-adjustable high-power photonic microwave generation based on wide-bandgap photoconductive semiconductors
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作者 荀涛 牛昕玥 +7 位作者 王朗宁 张斌 姚金妹 易木俣 杨汉武 侯静 刘金亮 张建徳 《Chinese Optics Letters》 SCIE EI CAS CSCD 2024年第1期113-122,共10页
Radio frequency/microwave-directed energy sources using wide bandgap SiC photoconductive semiconductors have attracted much attention due to their unique advantages of high-power output and multi-parameter adjustable ... Radio frequency/microwave-directed energy sources using wide bandgap SiC photoconductive semiconductors have attracted much attention due to their unique advantages of high-power output and multi-parameter adjustable ability.Over the past several years,benefitting from the sustainable innovations in laser technology and the significant progress in materials technology,megawatt-class output power electrical pulses with a flexible frequency in the P and L microwave wavebands have been achieved by photoconductive semiconductor devices.Here,we mainly summarize and review the recent progress of the high-power photonic microwave generation based on the SiC photoconductive semiconductor devices in the linear modulation mode,including the mechanism,system architecture,critical technology,and experimental demonstration of the proposed high-power photonic microwave sources.The outlooks and challenges for the future of multi-channel power synthesis development of higher power photonic microwave using wide bandgap photoconductors are also discussed. 展开更多
关键词 high-power photonic microwave wide bandgap photoconductive semiconductor devices linear modulation multi-parameter adjustable microwave generation multi-channel power synthesis
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Microwave damage susceptibility trend of a bipolar transistor as a function of frequency 被引量:9
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作者 马振洋 柴常春 +4 位作者 任兴荣 杨银堂 陈斌 宋坤 赵颖博 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期565-570,共6页
We conduct a theoretical study of the damage susceptibility trend of a typical bipolar transistor induced by a high-power microwave (HPM) as a function of frequency. The dependences of the burnout time and the damag... We conduct a theoretical study of the damage susceptibility trend of a typical bipolar transistor induced by a high-power microwave (HPM) as a function of frequency. The dependences of the burnout time and the damage power on the signal frequency are obtained. Studies of the internal damage process and the mechanism of the device are carried out from the variation analysis of the distribution of the electric field, current density, and temperature. The investigation shows that the burnout time linearly depends on the signal frequency. The current density and the electric field at the damage position decrease with increasing frequency. Meanwhile, the temperature elevation occurs in the area between the p-n junction and the n n+ interface due to the increase of the electric field. Adopting the data analysis software, the relationship between the damage power and frequency is obtained. Moreover, the thickness of the substrate has a significant effect on the burnout time. 展开更多
关键词 bipolar transistor high-power microwave FREQUENCY
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Hardening measures for bipolar transistors against microwave-induced damage 被引量:3
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作者 柴常春 马振洋 +3 位作者 任兴荣 杨银堂 赵颖博 于新海 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期637-641,共5页
In the present paper we study the influences of the bias voltage and the external components on the damage progress of a bipolar transistor induced by high-power microwaves. The mechanism is presented by analyzing the... In the present paper we study the influences of the bias voltage and the external components on the damage progress of a bipolar transistor induced by high-power microwaves. The mechanism is presented by analyzing the variation in the internal distribution of the temperature in the device. The findings show that the device becomes less vulnerable to damage with an increase in bias voltage. Both the series diode at the base and the relatively low series resistance at the emitter, Re, can obviously prolong the burnout time of the device. However, Re will aid damage to the device when the value is sufficiently high due to the fact that the highest hot spot shifts from the base-emitter junction to the base region. Moreover, the series resistance at the base Rb will weaken the capability of the device to withstand microwave damage. 展开更多
关键词 bipolar transistor high-power microwave hardening measures
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Dependence of plasma structure and propagation on microwave amplitude and frequency during breakdown of atmospheric pressure air 被引量:1
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作者 Pengcheng ZHAO Chao CHANG +1 位作者 Panpan SHU Lixin GUO 《Plasma Science and Technology》 SCIE EI CAS CSCD 2021年第8期38-46,共9页
The structure and propagation of the plasma in air breakdown driven by high-power microwave have attracted great interest.This paper focuses on the microwave amplitude and frequency dependence of plasma formation at a... The structure and propagation of the plasma in air breakdown driven by high-power microwave have attracted great interest.This paper focuses on the microwave amplitude and frequency dependence of plasma formation at atmospheric pressure using one two-dimensional model,which is based on Maxwell’s equations coupled with plasma fluid equations.In this model,we adopt the effective electron diffusion coefficient,which can describe well the change from free diffusion in a plasma front to ambipolar diffusion in the bulk plasma.The filamentary plasma arrays observed in experiments are well reproduced in the simulations.The density and propagation speed of the plasma from the simulations are also close to the corresponding experimental data.The size of plasma filament parallel to the electric field decreases with increasing frequency,and it increases with the electric field amplitude.The distance between adjacent plasma filaments is close to one-quarter wavelength under different frequencies and amplitudes.The plasma propagation speed shows little change with the frequency,and it increases with the amplitude.The variations of plasma structure and propagation with the amplitude and frequency are due to the change in the distribution of the electric field. 展开更多
关键词 air breakdown PLASMA IONIZATION high-power microwave plasma fluid equations
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A New Theoretical Technique for the Measurement of High-Frequency Relic Gravitational Waves 被引量:3
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作者 R. Clive Woods Robert M L Baker +3 位作者 Fangyu Li Gary V Stephenson Eric W Davis Andrew W Beckwith 《Journal of Modern Physics》 2011年第6期498-518,共21页
Under most models of the early universe evolution, high-frequency gravitational waves (HFGWs) were produced. They are referred to as “relic” high-frequency gravitational waves or HFRGWs and their detection and measu... Under most models of the early universe evolution, high-frequency gravitational waves (HFGWs) were produced. They are referred to as “relic” high-frequency gravitational waves or HFRGWs and their detection and measurement could provide important information on the origin and development of our Universe – information that could not otherwise be obtained. So far three instruments have been built to detect and measure HFRGWs, but so far none of them has achieved the required sensitivity. This paper concerns another detector, originally proposed by Baker in 2000 and patented, which is based upon a recently discovered physical effect (the Li effect);this detector has accordingly been named the “Li-Baker detector.” The detector has been a joint development effort by the P. R. China and the United States HFGW research teams. A rigorous examination of the detector’s performance is important in the ongoing debate over the value of attempting to construct a Li-Baker detector and, in particular, an accurate prediction of its sensitivity in the presence of significant noise will decide whether the Li-Baker detector will be capable of detecting and measuring HFRGWs. The potential for useful HFRGW measurement is theoretically confirmed. 展开更多
关键词 high-frequency GRAVITATIONAL WAVES high-frequency Relic GRAVITATIONAL Wave Measurement Primordial GRAVITATIONAL WAVES microwaves COSMOLOGY General RELATIVITY
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Mechanical-electrical synergy damage effect on GaN HEMT under high-power microwave 被引量:1
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作者 WANG Lei CHAI ChangChun +3 位作者 ZHAO TianLong LI FuXing QIN YingShuo YANG YinTang 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2023年第8期2373-2380,共8页
High-power microwave damage to enhanced-mode Ga N high electron mobility transistors(HEMT)is studied considering the mechanical-electrical synergy effect due to the strong piezoelectric properties of Ga N,which has a ... High-power microwave damage to enhanced-mode Ga N high electron mobility transistors(HEMT)is studied considering the mechanical-electrical synergy effect due to the strong piezoelectric properties of Ga N,which has a wurtzite crystal structure.Based on the piezoelectric constitutive equation,the mechanical and electrical energies were equivalently coupled,and the effective numerical model was built in the simulation software.The results indicated that a part of the electrical energy was stored in the device as a form of elastic energy,causing the burnout time of Ga N HEMT to be extended.The effects of different injection voltages and frequencies were analyzed,and the results revealed that elastic energy plays a different role during the process of device damage.These results are of great significance for the design of Ga N HEMTs with better reliability in harsh electromagnetic environments and for improving their protection design. 展开更多
关键词 GaN HEMT mechanical-electrical synergy damage electromechanical coupling elastic energy high-power microwave
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High-frequency gravitational waves having large spectral densities and their electromagnetic response
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作者 李芳昱 文毫 方祯云 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期104-112,共9页
Various cosmology models, brane oscillation scenarios, interaction of interstellar plasma with intense electromagnetic radiation, and even high-energy physics experiments (e.g., Large Hadron Collider (LHC)) all pr... Various cosmology models, brane oscillation scenarios, interaction of interstellar plasma with intense electromagnetic radiation, and even high-energy physics experiments (e.g., Large Hadron Collider (LHC)) all predict high frequency gravitational waves (HFGWs, i.e., high-energy gravitons) in the microwave band and higher frequency region, and some of them have large energy densities. Electromagnetic (EM) detection to such HFGWs would be suitable due to very high frequencies and large energy densities of the HFGWs. We review several typical EM detection schemes, i.e., inverse Gertsenshtein effect (G-effect), coupling of the inverse G effect with a coherent EM wave, coupling of planar superconducting open cavity with a static magnetic field, cylindrical superconducting closed cavity, and the EM sychro-resonance system, and discuss related minimal detectable amplitudes and sensitivities. Furthermore, we give some new ideas and improvement ways enhancing the possibility of measuring the HFGWs. It is shown that there is still a large room for improvement for those schemes to approach and even reach up the requirement of detection of HFGWs expected by the cosmological models and high-energy astrophysical process. 展开更多
关键词 high-frequency gravitational waves electromagnetic response of high-frequency gravitational waves superconducting microwave cavities synchro-resonance system
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Theoretical Analysis of the Interaction between the High-Power Microwave and the Electronic Circuits 被引量:1
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作者 杨一明 朱占平 +1 位作者 曾继来 钱宝良 《Chinese Physics C》 SCIE CAS CSCD 北大核心 2008年第z1期184-186,共3页
A simple theoretical model based on plasma physics is presented to analyze the microwave plasma effects on the electronic circuits.Results show that under certain parameter conditions the threshold for damaging the el... A simple theoretical model based on plasma physics is presented to analyze the microwave plasma effects on the electronic circuits.Results show that under certain parameter conditions the threshold for damaging the electronic circuits decreases with the decrease of the frequency of the high-power microwave.In addition,the oscillation amplitudes of the plasma electrons increase dramatically when the plasma frequency is near the high-power microwave frequency, which can easily damage the electronic circuits. 展开更多
关键词 high-power microwave electronic circuits PLASMA harassment threshold value
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Experimental research based on a C-band compact transit-time oscillator with a novel diode loading an embedded soft magnetic material and shielding structure
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作者 何宇放 贺军涛 +2 位作者 令钧溥 王蕾 宋莉莉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期428-434,共7页
In order to reduce the external magnetic field and improve the conversion efficiency of high-power microwave generation devices with low external magnetic field,a novel diode with an embedded soft magnetic and shieldi... In order to reduce the external magnetic field and improve the conversion efficiency of high-power microwave generation devices with low external magnetic field,a novel diode with an embedded soft magnetic and shielding structure is proposed.The soft magnetic material is designed to enhance the local magnetic field in the diode region.Moreover,the diode applies a shielding structure which can reduce the radial electric field.From simulation research,it is found that the emission and transmission quality of the electron beam with low magnetic field is greatly improved when loading this diode.Through simulation research,it is verified that the diode can increase the conversion efficiency of the transit-time oscillator(TTO)from 30%to 36.7%.In our experimental study,under the conditions of a diode voltage of 540 kV and a current of 10.5 kA,the output microwave power is 1.51 GW when loading the novel diode and the microwave frequency is 4.27 GHz when an external guiding magnetic field of 0.3 T is applied.The corresponding conversion efficiency is improved from 20.0%to 26.6%,which is 6.6%higher than that of a device loaded with a conventional diode.Our experiments have verified that this novel diode can effectively improve the conversion efficiency of high-power microwave sources operating with low magnetic field,and contribute to the miniaturization and compactness of high-power microwave devices. 展开更多
关键词 high-power microwave soft magnetic material shielding structure transit-time oscillator
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Investigation of an X-band magnetically insulated transmission line oscillator 被引量:4
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作者 樊玉伟 钟辉煌 +6 位作者 李志强 舒挺 杨汉武 杨建华 王勇 罗玲 赵延宋 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第5期1804-1808,共5页
An X-band magnetically insulated transmission line oscillator (MILO) is designed and investigated numerically and experimentally for the first time. The X-band MILO is optimized in detail with KARAT code. In simulat... An X-band magnetically insulated transmission line oscillator (MILO) is designed and investigated numerically and experimentally for the first time. The X-band MILO is optimized in detail with KARAT code. In simulation, the X-band MILO, driven by a 720 kV, 53 kA electron beam, comes to a nonlinear steady state in 4.0 ns. High-power microwaves (HPM) of TEM mode is generated with an average power of 4.1 GW, a frequency of 9.3 GHz, and power conversion efficiency of 10.870 in durations of 0-40 ns. The device is fabricated according to the simulation results. In experiments, when the voltage is 400 kV and the current is 50 kA, the radiated microwave power reaches about 110 MW and the dominating frequency is 9.7GHz. Because the surfaces of the cathode end and the beam dump are destroyed, the diode voltage cannot increase continuously. However, when the diode voltage is 400 kV, the average power output is obtained to be 700 MW in simulation. The impedance of the device is clearly smaller than the simulation prediction. Moreover, the duration of the microwave pulse is obviously shorter than that of the current pulse. The experimental results are greatly different from the simulation predictions. The preliminary analyses show that the generations of the anode plasma, the cathode flare and the anode flare are the essential cause for the remarkable deviation of the experimental results from the simulation predictions. 展开更多
关键词 magnetically insulated transmission line oscillator (MILO) high-power microwaves(HPM) pulse shortening
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Compact intense electron-beam accelerators based on high energy density liquid pulse forming lines 被引量:2
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作者 Jianhua Yang Zicheng Zhang +8 位作者 Hanwu Yang Jun Zhang Jinliang Liu Yi Yin Tao Xun Xinbing Cheng Yuwei Fan Zhenxing Jin Jinchuan Ju 《Matter and Radiation at Extremes》 SCIE EI CAS 2018年第6期278-292,共15页
This paper provides a review of the compact intense electron-beam accelerators (IEBAs) based on liquid pulse forming lines (PFLs) that havebeen developed at the National University of Defense Technology (NUDT) in Chin... This paper provides a review of the compact intense electron-beam accelerators (IEBAs) based on liquid pulse forming lines (PFLs) that havebeen developed at the National University of Defense Technology (NUDT) in China. The history and roadmap of the compact IEBAs used todrive high-power microwave (HPM) devices at NUDT are reviewed. The properties of both de-ionized water and glycerin as energy storagemedia are presented. Research into the breakdown properties of liquid dielectrics and the desire to maximize energy storage have resulted in theinvention of several coaxial PFLs with different electromagnetic structures, which are detailed in this paper. These high energy density liquidPFLs have been used to increase the performance of IEBA subsystems, based on which the SPARK (Single Pulse Accelerator with spark gaps)and HEART (High Energy-density Accelerator with Repetitive Transformer) series of IEBAs were constructed. This paper also discusses howthese compact IEBAs have been used to drive typical HPM devices and concludes by summarizing the associated achievements and theconclusions that can be drawn from the results. 展开更多
关键词 high-power microwave(HPM) Intense electron-beam accelerator(IEBA) Pulsed power technology(PPT) Pulse forming line(PFL) Fluid of high energy density De-ionized water GLYCERIN
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