2022 Vol. 34, No. 5

Recommend Articles
Actinide nuclear targets preparation and applications
He Yao, Li Gang, Chen Qiping, Hu Rui, Deng Jian, Yang Yuchuan, Tu Jun, Peng Shuming
2022, 34: 056001. doi: 10.11884/HPLPB202234.210507
17.4 kW (1+1) long distance side-pumped laser fiber
Gao Cong, Liu Nian, Li Fengyun, Liu Yu, Dai Jiangyun, Shen Changle, He Hongle, Lü Jiakun, Li Fang, Zhang Lihua, Li Yuwei, Jiang Lei, Guo Chao, Tao Rumao, Ke Weiwei, Zhang Haoyu, Wang Jianjun, Lin Honghuan, Jing Feng
2022, 34: 051002. doi: 10.11884/HPLPB202234.220070
Research advances in ultrafast X-ray free-electron lasers
Jia Haoyan, Huang Senlin, Jiao Yi, Li Jingyi, Liu Kexin, Liu Shuai, Liu Weihang, Liu Zhongqi, Long Tianyun, Qin Weilun, Zhao Sheng
2022, 34: 054001. doi: 10.11884/HPLPB202234.220056
Cover and Contents
Cover and Contents, High Power Laser and Particle Beams, No 5, Vol 34, 2022
Editorial Office
2022, 34: 1-2.
Feature Issue on Application Technology of Research Reactor
Actinide nuclear targets preparation and applications
He Yao, Li Gang, Chen Qiping, Hu Rui, Deng Jian, Yang Yuchuan, Tu Jun, Peng Shuming
2022, 34: 056001. doi: 10.11884/HPLPB202234.210507
Abstract:

There is an increasing demand on precise, accurate and reliable experimental nuclear data in various scientific research fields like basic nuclear physics, nuclear energy, super-heavy element research and others. Actinide targets are composed of a thin-layer, pure actinide compound deposited on a certain metal foil. Acting as the stationary nuclei sources in nuclear reactions, high-quality actinide targets are essential for the uncertainty of the measured nuclear data and ensure the success of the relative experiments. In this review, the preparation methods of actinide nuclear targets, the development of organizations of nuclear targets, and the outlook are discussed.

Neutron irradiation effects of graphite serving in SPRR-300 reactor
Zheng Jian, Yan Zhanfeng, Wang Hao, Feng Qijie, Liu Xiankun, Liu Xiao, Wang Shuyu, Zhou Wei, Qian Dazhi
2022, 34: 056002. doi: 10.11884/HPLPB202234.210511
Abstract:
During the long period service in the SPRR-300 research reactor, the graphite box in the vicinity of the core has been irradiated for about 30 years. In this paper, we take samples from the graphite box and investigate the changes of the thermal, mechanical properties and microstructure, compare them with those of the commercial IG110 and NG-CT-10 graphite. We find that after the long-time service, the low fluence neutron irradiation has induced tremendous irradiation damage defects in the crystal structures of the SPRR-300 graphite. These defects are mainly dislocation loops, stacking faults, voids, microcracks, et al. A degree of amorphization has also been observed. Comparing with those of the IG110 and NG-CT-10 graphite, the coefficients of thermal expansion, thermal diffusivity, compression strength and the flexural strength of the SPRR-300 graphite decrease while the modulus of elasticity in flexure increase. The changes of the thermal and mechanical properties of the SPRR-300 graphite may due to the irradiation-induced defects.
Safety boundary of flow channel partial blockage in plate-type fuel assembly
Ding Wenjie, Wang Shaohua, Gao Jiao, Guo Haibing, Ma Jimin, Liu Zhiyong
2022, 34: 056003. doi: 10.11884/HPLPB202234.210508
Abstract:
It is necessary to obtain the triggering boundaries of heat transfer deterioration by mastering the flow and heat transfer characteristics in plate-type fuel assembly with multiple channels blocked, to improve the operation safety of plate-type fuel reactors. Based on qualitative analysis, the flow channel partial blockage accidents can be divided into non-adjacent channel blockage accident and adjacent channel blockage accident for the standard fuel assembly of the typical plate-type fuel reactor JRR-3M. Furthermore, the simulations of the flow and heat transfer characteristics under the two types of accidents were carried out using the computational fluid dynamics software ANSYS Fluent. The simulation results show that local boiling will not occur in flow channels and the maximum fuel temperature will be lower than the allowable temperature when non-adjacent channels are completely blocked or the maximum blocking rate of adjacent channels is less than 35%. Therefore, the safety operation boundary of JRR-3M reactor under flow channel blockage accident can be determined.
Mathematical model establishment, simulation and reconstruction of PGAI
Ma Yuhua, Li Hang, Yang Xin, Li Rundong, Huang Hongwen
2022, 34: 056004. doi: 10.11884/HPLPB202234.210551
Abstract:
In the prompt gamma activation imaging, the neutron self-shielding and gamma self-absorption effect inside the sample will cause uneven distribution of the measurement results. To solve the problem of the biased distribution in the prompt gamma activation imaging, the influence of the neutron field inside the sample and the self-absorption effect of gamma were studied, and the transport process of neutrons and gamma rays was theoretically deduced. A mathematical model for correcting the biased distribution and image reconstruction was established. The Monte Carlo method was used to simulate the prompt gamma activation imaging of Fe and H elements, and the mathematical model was used to reconstruct the element images. The results show that the influence of neutron self-shielding and γ self-absorption effect in prompt gamma activation imaging has been significantly corrected, and the content distribution of Fe and H elements can be accurately reconstructed using this mathematical model, which verify the validity of the mathematical model.
Preliminary application of neutronics calculation in LFR reactor with metallic fuel using dragon code
Zhang Liang, Sun Sheng, Sun Shouhua, Yang Wenhua
2022, 34: 056005. doi: 10.11884/HPLPB202234.220001
Abstract:
Lead-bismuth/lead cooled fast reactor (LFR) is one of the fourth-generation advanced nuclear energy systems with good application prospects. Aiming at the application of two metallic fuels (UZr, UPuZr) with annular slug in an LFR fuel assembly and a typical LFR core, the Dragon/Donjon code was used to perform neutronics calculations. The results of 172-group and 295-group neutron databases based on the ENDF/B 8.0 library and the transport method (SP3) and the diffusion method (MCFD) were obtained and compared with the results using RMC code. The keff deviations using SP3 algorithm for UZr fuel are less than 550×10−5, and for UPuZr fuel, the keff deviations obtained by MCFD algorithm are less than −700×10−5. The maximum deviation of control rod worth is 7.6%, and the results using 172-grouplib and 295-grouplib are basically the same. By using the SP3 algorithm, the fuel assembly power deviations are less than ±6.0%, and the deviation with the SP3 algorithm is less than that with MCFD algorithm. The results preliminarily prove the feasibility of the Dragon/Donjon code for reactor physics analysis of LFR with metallic fuel.
Asymmetrical operation characteristics of natural circulation lead-bismuth reactor under ocean conditions
Wang Xu, Zhao Ya’nan, Zhao Pengcheng, Yu Tao
2022, 34: 056006. doi: 10.11884/HPLPB202234.210474
Abstract:
To ensure the vitality of naval nuclear power at all times, the natural cycle lead-bismuth reactor loop will take partial loop operation when it fails under marine conditions. However, there are few studies on the partial loop operation characteristics of lead-bismuth reactor under marine conditions. Based on the secondary development of RELAP5/MOD3.1 program, the off-loop operation characteristics of a 10 MW natural cycle lead-bismuth reactor under typical oceanic conditions are analyzed. The analysis results show that the system parameters of the reactor are less sensitive to the change of tilt angle when the reactor is operating under inclined conditions. Under undulating conditions, the fluctuation of flow rate is reduced by 9% and the outlet temperature is reduced by about 16 K. The larger the undulating amplitude, the more drastic the flow rate fluctuation; the larger the undulating period, the more obvious the flow rate oscillation, but the effect is also weakening. Under rocking conditions, the core flow and outlet temperature are reduced and the reactor introduces higher safety margins. The larger the swing amplitude and the smaller the swing period, the larger the flow fluctuation, and the core outlet temperature is significantly more sensitive to the cycle change than the swing amplitude change.
Intelligent optimization method for lead-bismuth reactor based on Kriging surrogate model
Li Qiong, Liu Zijing, Xiao Hao, XiaoYingjie, Zhao Pengcheng, Wang Chang, Yu Tao
2022, 34: 056007. doi: 10.11884/HPLPB202234.210560
Abstract:
The extensive application requirements of lead-bismuth reactors require researchers to carry out a lot of optimization design work on the basis of existing core schemes. Aiming at the multi-dimensional nonlinear constrained optimization design problem of lead-bismuth reactor with multi-physical, multi-variable and multi-constraint coupling effects, an intelligent optimization method for lead-bismuth reactor was constructed based on Kriging surrogate model, orthogonal Latin hypercube sampling and SEUMRE spatial search technology. Coupled with physical Monte Carlo calculation/thermal ranalysis code, an optimization platform including sampling, pre-and post-processing of coupling program and reactor optimization analysis function was developed. Taking SPALLER-4 and URANUS as prototypes, the scheme optimization and parameter optimization verification of minimum fuel load were carried out respectively. The verification results show that the core intelligent optimization method is feasible and effective for the optimization of lead-bismuth reactor design scheme and core parameters. Compared with the traditional Monte Carlo calculation optimization, the calculation cost is greatly reduced under the premise of ensuring the prediction accuracy. Compared with the URANUS initial model, the fuel loading, the total mass of the core, the volume of the active zone and the total volume of the core are optimized by 10.8%, 11.5%, 18.1% and 17.1% respectively, which provides a reference for the intelligent optimization method based on the surrogate model applied to the optimization design of lead-bismuth reactor.
The self-ion irradiation effects in 6061-Al alloy
Yan Zhanfeng, Zheng Jian, Zhou Wei, Wang Hao
2022, 34: 056008. doi: 10.11884/HPLPB202234.210509
Abstract:
Aluminum alloy is the main structural material of research reactors at home and abroad. In this paper, on the basis of the research on the irradiation damage of the structural material aluminum alloy in the 300# research reactor, the microstructural damage and hardness change caused by ion irradiation in 6061-Al alloy are studied to carry out the early exploration of the damage effect of 6061-Al alloy under higher neutron irradiation doses. The results show that 1/3<111> dislocation loops with angles of 72° are generated in 6061-Al alloy after self-ion irradiation. The defect density increases obviously with the increasing irradiation dose from 0.218×1016 cm−2 to 4.367×1016 cm−2. However, the selected area electron diffraction shows a good lattice structure and no amorphous transformation occurs. Nano-indentation test demonstrates obvious irradiation hardening after irradiation and the microhardness increases with the increasing doses. At the highest damage dose of 2.183×1016 cm−2 and 4.367×1016 cm−2, the hardening reaches saturation, approaching 11%. These results can provide data support for the preliminary prediction of the structure and property change in 6061-Al alloy under high neutron irradiation dose.
Size measurements of beryllium assemblies after long term service
Liu Xiao, Yang Wankui, Wang Hao, Wang Jian, Zhang Songbao, Zhang Xinrong, Li Wenhua
2022, 34: 056009. doi: 10.11884/HPLPB202234.210516
Abstract:
Beryllium is an important material as neutron reflection layers in nuclear reactors. The size change of beryllium after long term neutron irradiation has a great influence on the reactor safety. To obtain the size change of beryllium assemblies after long-time irradiation for the assessment of service performance, a set of special tools were designed and manufactured. The size change of post-irradiation beryllium assemblies was examined on a three coordinate measuring machine. The measurement results indicate that beryllium assemblies of the SPRR-300 reactor have excellent stability after 29 a irradiation, even under the maximum neutron fluence of 6.78×1021 cm−2. The section dimension has little change in local part of beryllium assemblies and the largest change is about 0.13 mm, which indicates that irradiation creep is the main reason for the dimension change of beryllium assemblies during the long-time service.
Investigation into optimum design of recuperator at a confirmed heat transfer area
Gao Jiao, Wang Shaohua, Huang Hongwen
2022, 34: 056010. doi: 10.11884/HPLPB202234.210521
Abstract:
This study aims to investigate the heat transfer characteristics of supercritical CO2 when flowing through the printed circuit heat exchanger with Z type channel, and further guide the optimum design of recuperator at confirmed heat transfer area. Numerical simulation is used to analyze the local and overall heat transfer characteristics between CO2 at two pressures. The heat transfer characteristics of a recuperator with typical structure are calculated at a typical working condition, and compared to the experimental results to check the computation model. Then, the heat transfer characteristics of the recuperator with the same heat transfer area but different channel structure are calculated. The effect law of the structure on heat transfer is explored. The study shows that the calculation results have good agreement with the experimental results. The heat transfer coefficient decreases the most when the channel included angle increases from 110° to 115°and the advised range is 110°−120° for different design requirements.
A supercritical carbon dioxide cycle efficiency analysis
Wang Shaohua, Gao Jiao, Ding Wenjie, Huang Hongwen, Guo Haibing, Ma Jimin, Liu Zhiyong
2022, 34: 056011. doi: 10.11884/HPLPB202234.210528
Abstract:
The supercritical carbon dioxide (S-CO2) Brayton cycle is a new type of power generation technology with broad application prospects. This paper takes the supercritical carbon dioxide simple Brayton cycle with recuperation as the research object, and takes the nuclear power plant as the application background. The system cycle model and the efficiency model of the key components is discussed in detail. Based on this model, the influence of various engineering factors on the efficiency of the Brayton cycle and the volume of the system has been discussed. The analysis results show that the sensitivity of cycle efficiency and system volume to parameters such as temperature, pressure, turbomachinery efficiency and regenerator design differs obviously, and the most effective method to reduce the system volume is increasing the turbine inlet temperature. It is necessary to establish a complete system analysis model to optimize the design of the S-CO2 system.
High Power Laser Physics and Technology
Large core air cladding micro structured optical fiber for kW laser transmission
Xia Changming, Huang Zhuoyuan, Liu Jiantao, Yang Jiahao, Mo Zhifeng, Hou Zhiyun, Zhou Guiyao
2022, 34: 051001. doi: 10.11884/HPLPB202234.210452
Abstract:

Kilowatt high power laser flexible transmission is a necessary link in the field of high power laser processing such as laser cleaning, laser welding, laser etching, and the low loss optical fiber with bend loss is the key device to realize high power laser transmission. At present, high power laser transmission fiber adopts large core diameter fiber, but there are some problems, such as large bending loss, poor flexibility and so on. Therefore, a large core diameter air clad micro structure optical fiber is proposed. The air holes in the fiber cladding can greatly reduce the risk of laser leakage, reduce the strict requirements of high temperature coating in the process of fiber preparation, and achieve kW laser output, thus offer the foundation for the flexible transmission of 10 kW high-power laser.

17.4 kW (1+1) long distance side-pumped laser fiber
Gao Cong, Liu Nian, Li Fengyun, Liu Yu, Dai Jiangyun, Shen Changle, He Hongle, Lü Jiakun, Li Fang, Zhang Lihua, Li Yuwei, Jiang Lei, Guo Chao, Tao Rumao, Ke Weiwei, Zhang Haoyu, Wang Jianjun, Lin Honghuan, Jing Feng
2022, 34: 051002. doi: 10.11884/HPLPB202234.220070
Abstract:

The long distance side-pumped laser fiber (LDSPF) is characterized by its ability for high power pump power coupling, heat management and nonlinear effect suppressing, which is quite potential for high power fiber laser application.A (1+1) LDSPF for tandem pumping was fabricated and tested. Pumped by 1018 nm fiber lasers, 17.4 kW laser output at 1080 nm with a slope efficiency of 82.1% was achieved with this fiber amplifier with backward pumping technique. Linewidth at 3 dB of the laser is 1.3 nm and the ratio of signal light to SRS is around 37.8 dB at the maximum power. The results demonstrate great potential of LDSPF as power amplifier for tens of kilowatts fiber laser.

Focusing characteristics of Riemann-Silberstein vortices of edge-dislocation Gaussian beam passing through a bifocal lens
Yan Hongwei
2022, 34: 051003. doi: 10.11884/HPLPB202234.210317
Abstract:
Based on the zeros of the time-averaged complex scalar field, the complex scalar field of Riemann-Silberstein (RS) vortices generated by the edge dislocation line embedded in the Gaussian beam propagating through the bifocal lens is derived. The focal characteristics of the RS vortices are studied in detail, and the influence of the propagation distance and the focal length of the bifocal lens on the RS vortices is nalyzed. It is found that the RS vortices will move after passing through the bifocal lens, a new pair of RS vortices with opposite topological charge will be generated, and two RS vortices with opposite topological charge will gradually approach each other to annihilation. However, during the entire focusing process, the total topological charge of the RS vortices is conserved. In particular, when the RS vortices pass through an ideal lens, there are always only four RS vortices on the x-axis in the complex scalar field. As the propagation distance increases, these four RS vortices gradually approach the origin (0, 0), and then gradually move away from the origin (0,0), but the topological charge of each RS vortex has remained unchanged, thus the total topological charge is conserved.
Inertial Confinement Fusion Physics and Technology
Online diagnosis system for D3He proton in laser fusion implosion experiments
Teng Jian, Deng Zhigang, Shan Lianqiang, Wen Jiaxing, Yuan Zongqiang, Wang Weiwu, Zhang Tiankui, Tian Chao, Zhang Feng, Yu Minghai, Lu Feng, Hong Wei, He Shukai, Zhang Zhimeng, Qi Wei, Cui Bo, Xu Qiuyue, Wei Lai, Li Yingjie, Xia Liqiong, Zhang Xing, Wu Yuchi, Su Jingqin, Zhou Weimin, Gu Yuqiu
2022, 34: 052001. doi: 10.11884/HPLPB202234.210497
Abstract:
An online magnetic spectrometer system based on a hybrid pixel detector is proposed for the diagnosis of the D3He proton spectrum and yield in laser fusion implosion experiments. By identifying the number and energy of the track clusters and considering the experiment setup, the proton spectrum and yield could be deduced in time. The online diagnosis system is tested on the SG laser facility, in which 31 laser beams are focused on the capsule to drive the fusion reaction. With D2 and 3He gas mixed 1∶1 by atomic ratio, the primary D3He proton energy spectrum with center energy of 14.6 MeV, FWHM of 2.1 MeV, and yield of 2.3×109 is obtained. This system could provide the D3He proton spectrum and yield online, which would be helpful to improve the experiment in time.
Investigation into preparation of thin-walled polystyrene hollow microspheres for ICF
Xu Wenting, Li Jie, Liu Yiyang, Chen Qiang, Yi Yong, Liu Meifang
2022, 34: 052002. doi: 10.11884/HPLPB202234.210557
Abstract:
As an effective way to explore controlled nuclear fusion, laser inertial confinement fusion (ICF) is expected to obtain clean and pollution-free energy. Thin-walled polystyrene (PS) hollow microspheres are a type of microspheres urgently needed in ICF physics experiments. Thin-walled hollow microspheres are easy to crack while drying and being used due to the increase in diameter-to-thickness ratio (diameter/wall thickness). In this work, the influence of the PS materials on the quality of thin-walled microspheres was studied, and the mechanism was discussed. The results show that when the oil phase (PS) mass fraction was 4%, the stability of W1/O/W2 composite emulsion particles gradually increased with the increase of oil phase viscosity; when the oil phase mass fraction was not less than 8%, the stability of compound droplets was fine. There is no significant difference in the surface roughness of the corresponding microspheres. The sphericity and wall thickness uniformity of microspheres decreased with the increase of initial oil phase viscosity. In the drying process, the cracking rate of microspheres decreased with the increase of oil phase viscosity. The rate of microsphere cracking decreases as the mechanical properties of the raw material improves. To compensate for the adverse effect of the increase in oil phase viscosity on the sphericity and uniformity of the wall thickness of the microspheres, fluorobenzene (FB) droplets were introduced into the external water phase to reduce the solidification rate.
High Power Microwave Technology
Prediction of coupling cross section of hexagonal aperture array based on BP neural network
He Zhibin, Yan Liping, Zhao Xiang
2022, 34: 053001. doi: 10.11884/HPLPB202234.210566
Abstract:
As an important parameter to measure the leakage of electromagnetic energy through apertures, there has not been a universal, fast and high precision method to obtain the coupling cross section (CCS). For obtaining the hexagonal aperture array normalized CCS, we analyze the influence of various factors on it under the condition of vertical incidence. A total of 13820 sets of CCS data are obtained by selecting appropriate parameters and using full-wave analysis method. After some input parameters are preprocessed and the neural network is trained, a BP neural network model has been constructed with seven parameters including the electrical dimension of the aperture unit, row/column number, the electrical dimension of the row/column distance, the electrical dimension of the aperture wall thickness and polarization angle of incident wave as the input and the normalized CCS as the output. The model has an average relative error of 3.8% when the predicted normalized CCS of the hexagonal aperture array has the electrical dimensions [0.1, 1.2]. A total of 480 CCSs with input parameters not appearing in both the training set and the test set are predicted by the neural network and compared with the full-wave analysis results, and the average relative error is 7.27%. Finally, the universality and effectiveness of the model are validated further by experimental measurement.
Development and validation of electromagnetic coupling solver for electrically large-sized cavity structure based on power balance method
Hu Minglang, Zhou Shihua, Yan Liping, Zhao Xiang
2022, 34: 053002. doi: 10.11884/HPLPB202234.220026
Abstract:
The power balance (PWB) method is a fast method based on statistical electromagnetics for solving electromagnetic coupling problems in electrically large-sized cavity structures. Based on the PWB method, an electromagnetic coupling solver is developed to solve the electromagnetic coupling level of electrically large-sized cavity structure with different cavity shapes, different aperture shapes and different source types, etc. The validity and efficiency of the solver is validated by comparing its output with the results in the published literature and those of experiments.
Particle Beams and Accelerator Technology
Research advances in ultrafast X-ray free-electron lasers
Jia Haoyan, Huang Senlin, Jiao Yi, Li Jingyi, Liu Kexin, Liu Shuai, Liu Weihang, Liu Zhongqi, Long Tianyun, Qin Weilun, Zhao Sheng
2022, 34: 054001. doi: 10.11884/HPLPB202234.220056
Abstract:

Advances in modern light sources continue to improve our understanding of the fundamental structure and microscopic dynamics of matter. As the most advanced light source, X-ray free-electron lasers provide the brightest X-rays with ultrahigh peak power, ultrashort pulse length, and excellent coherence, making it possible to detect and manipulate ultrafast processes in atomic and molecular systems. X-ray free-electron laser facilities in operation worldwide have shown great value in the application fields of physics, chemistry, biology, material science, etc. Furthermore, many efforts have focused on improving the performance of X-ray free-electron lasers, including reducing the pulse duration from femtosecond to attosecond for opening new frontiers in ultrafast science. This paper mainly reviews the recent progress of ultrafast X-ray free-electron lasers and summarizes various schemes in terms of their generation mechanisms, unique properties and latest results. Finally, it predicts the future development of ultrafast X-ray free-electron lasers.

Simulation for measurement technique of electron beam divergence basing on Cherenkov radiation
Jiang Xiaoguo, Chi Zhijun, Liao Shuqing, Du Yingchao, Yang Guojun, Zhang Xiaoding, Li Hong, Yang Xinglin, Jiang Wei, Wei Tao, Wang Yuan
2022, 34: 054002. doi: 10.11884/HPLPB202234.210426
Abstract:
The direction of Cherenkov Radiation (CR) light is strictly defined by the direction along which the charged particle moves. This characteristic can be adopted to measure the electron beam divergence and it is a hopeful method. The Coulomb force on electron in the convertor expand the beam divergence and obviously reduce the measurement precision. A model of multi-slice in cascade connection is adopted to constitute convertor configuration. Taking into account the combined effect of Coulomb force, multiple scattering, bremsstrahlung and ionization, the deviation process of electron in the convertor material is then simulated by Monte-Carlo simulation. Measurement technique of electron beam divergence is further simulated basing on the principle of exact corresponding relationship between electron beam divergence distribution and CR photon distibution. Some effect on measurement are obtained for factors including convertor material, thickness, beam energy divergence and optical bandwidth of measurement system. The simulated results give many useful suggestions for the design of the measurement system and the image data processing. The simulation results obviously show the feasibility of electron beam divergence measurement basing on Cherenkov radiation and that its distribution can also be measured in a certain extent.
Pulsed Power Technology
Design of arbitrary polarity rectangular pulse power supply based on Marx
Jiang Song, Huang Lifei, Rao Junfeng, Wang Yonggang, Li Zi
2022, 34: 055001. doi: 10.11884/HPLPB202234.210405
Abstract:
Low temperature plasma produced by dielectric barrier discharge (DBD) is widely used in plasma medicine, environmental governance and other fields. The common driving source is high voltage pulse power supply. A rectangular pulse power supply based on Marx circuit is designed. The power supply combines the magnetic ring isolation drive scheme with the full-bridge Marx circuit to realize the output of positive, negative and bipolar high voltage rectangular pulses, which solves the limitation that the conventional pulse power supply can only output specific polarity pulses. The operation mode of the circuit is analyzed theoretically and the experimental prototype is built. Under no-load conditions, the pulse polarity can be adjusted and the amplitude of 10 kV high voltage pulse output is realized. The parallel plate dielectric barrier discharge reactor was successfully driven by the pulse power supply, which further verified the feasibility of the scheme.
Design and analysis of repetitive frequency inductor in high power and high energy storage pulse power supply
Wang Yan, Zhang Qin, Lin Fuchang, Li Hua
2022, 34: 055002. doi: 10.11884/HPLPB202234.210417
Abstract:
To meet the requirement of continuous discharge in the integrated system of high power pulse power supply a repeatitive frequency water-cooled inductor for the system was developed. In the system, the water-cooled inductor can not only adjust the current waveform of the power supply, but also play an isolation role. The repeatitive frequency water-cooled inductor can withstand high voltage, large current, charge interval period of 6 seconds, and can work continuously for 10 times of discharge capacity. To meet the requirement of continuous discharge, deionized circulating water is used to cool the inductor. Taking the single module energy of 334 kJ, inductance of 30 μH, and current of 100 kA as an example, the design and analysis are carried out to establish the temperature field simulation model of the inductor, and analysis is made on the transient characteristics of the internal temperature of the inductor through ANSYS simulation software. The results show that the inductor is well cooled by deionized water, and the maximum temperature of the inductor reaches 47 ℃ after each operation, and the temperature of the inductor recovers to 41 ℃ before the next operation point. At the same time, the inductor passes the 112 kA electrodynamic test without circulating water. The experimental results agree well with the theoretical analysis, and the inductor runs stably, which verifies the correctness of theoretical analysis and design.
Advanced Interdisciplinary Science
Surface plasmon resonance refractive index sensor based on microstructured fiber with air-hole
Tan Qilong, Zhang Xia, Kang Hu, Peng Zhiqing, Li Xiaowei, Yang Mochou, Feng Guoying
2022, 34: 059001. doi: 10.11884/HPLPB202234.220062
Abstract:
A photonic crystal fiber refractive index (RI) sensor based on enhanced surface plasmon resonance (SPR) effect is proposed. The sensor structure is spliced with a photonic crystal fiber (PCF) by a fiber fusion splicer, so that an air hole is introduced in the middle of the photonic crystal fiber to form a PCF-air hole-PCF optical fiber sensing structure. Then, a thin gold film is deposited on its surface by using magnetron sputtering coating process. Experiments are carried out to investigate the response of the refractive index and temperature of the sensor. The results show that in the refractive index (RI) range of 1.333−1.389, the sensor has an average RI sensitivity of 2 142.52 nm, with a linearity of 0.981 and a quality factor about 13.10. Experimental results show that the sensor is not sensitive to temperature. Compared with the PCF sensing structure without air hole, the air hole introduced enhances the SPR effect, so that the sensor has a good resonance peak depth. Benefiting from the above advantages, this type of sensor is expected to be applied in fields such as biomedicine and environmental monitoring.