最新刊期
      卷 45 ， 期 5 ， 2022

        SYNCHROTRON RADIATION TECHNOLOGY AND APPLICATIONS

      • “上海硬X射线自由电子激光装置SHINE采用低温超导高频腔加速电子，实现了8 GeV电子能量。研究者基于Zynq-UltraScale+型片上系统，设计并实现了丝扫描系统数据采集系统，通过实验验证了其同步采集功能，满足SHINE丝扫描截面测量系统的运行要求。”
        WAN Jun,LENG Yongbin,LAI Longwei,CHEN Jie,GAO Bo,CHEN Fangzhou,CHEN Jian,CAO Shanshan
        Vol. 45, Issue 5, Article number: 050101(2022) DOI: 10.11889/j.0253-3219.2022.hjs.45.050101
        摘要：BackgroundThe Shanghai high repetition rate XFEL and extreme light facility (SHINE) accelerates electrons up to 8 GeV using cryogenic-superconducting high-frequency cavity. Wire scanner system is applied to the beam profile measurement of SHINE due to its advantages such as fewer secondary particles generation compared with that of complete beam block, hence reduce the risk of superconducting cavity.PurposeThis study aims to design data acquisition system for wire scanner system and realize synchronous acquisition of beam loss signal and relative position between the wire and beam.MethodsThe data acquisition system for wire scanner was designed to include radio frequency (RF) daughter board with analog signal digitizer, digital motherboard, firmware, data processing software. A Zynq-UltraScale+ based system on chip (SoC) was employed as system central component, and a field programmable gate array (FPGA) was used for system control and data transmission whilst the advanced RISC machine (ARM) integrating Linux was implemented for data acquisition and communication. Finally, experimental test of this data acquisition system was performed on the testbed to verify its feasibility and functionalities.ResultsThe data acquisition system can correctly read back position of grating ruler, and achieve synchronous acquisition of sample beam loss signal and signal of cavity beam position monitor.ConclusionsThe data acquisition system meets the requirements of SHINE wire scanner system. It will be applied to the prototype of SHINE wire scanner system.  
        关键词：Wire scanner;SHINE;Synchronous signal acquisition;Electronics design   
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        发布时间：2024-10-25

        ACCELERATOR, RAY TECHNOLOGY AND APPLICATIONS

      • “在癌症治疗领域，基于7Li(p,n)反应的加速器中子源展现出巨大潜力。专家提出3 MeV质子轰击0.2 mm锂靶的设计方案，并通过模拟优化慢化体结构，获得满足BNCT需求的中子注量率和能谱。”
        GUO Zhiqi,LIU Changqi,ZHANG Weizhong,HU Zhiming,XU Dapeng,YAO Zeen
        Vol. 45, Issue 5, Article number: 050201(2022) DOI: 10.11889/j.0253-3219.2022.hjs.45.050201
        摘要：BackgroundBoron Neutron Capture Therapy (BNCT) has been widely recognized around the world as an effective cancer treatment. The accelerator neutron source based on 7Li(p,n) reaction has the advantages of low reaction threshold, high neutron yield, low average neutron energy and easy slowing down. It is the most promising accelerator neutron source for BNCT.PurposeThis study aims to design an accelerator-based neutron source for BNCT, and design a reasonable beam shaping model.MethodsThe Geant4 (GEometry And Tracking) program was used to simulate the neutron source characteristics of protons bombarding lithium targets with different thicknesses at different energies. The accelerator parameter design scheme was proposed by using a 0.2 mm thick lithium target bombarded with 3 MeV protons. Then, the neutron beam shaping assembly (BSA) model was designed and optimized. A combination of "26 cm MgF2 + 10 cm TiF3" was taken as the moderating layer structure with 6Li of 0.08 cm taken as thermal neutron absorption layer and Bi of 1.5 cm taken as γ absorption layer. Finally, simulation of accelerator proton beam at 15 mA was carried out to calculate the optimal material combination and thickness.ResultsSimulation results show that the rate of epithermal neutron flux at the outlet of the moderator reaches 1.16×109 n·cm-2·s-1, the ratio of fast neutron to epithermal neutron Φepi / Φfast is 21.64, the ratio of thermal neutron to epithermal neutron Φepi /Φth is 125.23, and the γ component Dγ /Φepi reaches 1.82×10-13 Gy·cm2·n-1 (epi).ConclusionsThe parameters at the BSA exit designed in this study meet BNCT requirements.  
        关键词：Boron neutron capture therapy;Monte Carlo simulation;Neutron source;Neutron slowing down   
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        发布时间：2024-10-25
      • “在“空间环境地面模拟装置”项目中，专家设计出高品质电子枪，优化了结构参数，引出1 µA~50 mA电子束。”
        ZHANG Haowei,WANG Shengli,LI Deming,HUANG Jianming
        Vol. 45, Issue 5, Article number: 050202(2022) DOI: 10.11889/j.0253-3219.2022.hjs.45.050202
        摘要：BackgroundGrid-controlled electron guns mostly use mesh grid and extract pulsed beam current; there is little research on the wide-range direct current beam.PurposeThis study aims to design a wide-range high-accuracy direct current electron gun to meet the requirement of the Low Energy Electron Accelerator and Beam Line.MethodsBased on the original diode electron gun, a control grid was added to improve the control range and accuracy of the accelerator to form a triode electron gun. Then, the CST Particle Studio was employed to simulate the influence of some structural parameters of the triode electron gun on the extracted beam current, and obtained simulation result of electron gun was verified by Particle Beam GUN Simulation (PBGUNS) software. Finally, the experimental verification of design scheme was carried out on the electron gun experimental platform for optimizing the structure of electron gun. Several main structure parameters were changed to adjust beam current.ResultsThe experimental results show the optimized electron gun structure can extract 1 µA~50 mA high-quality beam when using cathode primary heating voltage as coarse adjustment and grid voltage as fine adjustment.ConclusionsThe influence law of gun structure parameters on beam current in the experiment is verify by simulation. The optimized gun structure meets the project requirements.  
        关键词：Grid-controlled electron gun;Thermionic cathode;Direct current;Wide-range;High-accuracy   
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      • “在碳离子束流调制领域，研究人员模拟了新型多孔结构体PS 2.0，有效展宽布拉格峰，减小后沿半影宽度，保证束流均匀性，并在一定程度上减小等中心束斑大小。”
        DONG Sixue,SHENG Yinxiangzi,XIA Xiaobin
        Vol. 45, Issue 5, Article number: 050203(2022) DOI: 10.11889/j.0253-3219.2022.hjs.45.050203
        摘要：BackgroundIn particle radiotherapy, the Bragg peak (BP) width of carbon ion beam is required to be broadened whilst Ripple filter (RiFi) is often used as a clinical broadening device. However, it may cause extra lateral scattering. Porous material expressed as the porous structure 1.0 (PS 1.0) can be used to reduce such scattering but bring an oversized distal falloff width (DFW).PurposeThis study aims to develop a novel porous structure, described as a porous structure 2.0 (PS 2.0), to broaden the BP width.MethodsFirst of all, the Monte Carlo code, FLUKA was selected as the tool for this simulation. Two geometry models of broadening structure (1D-RiFi and PS 1.0) were built. Then, the PS 2.0 was simulated by inserting numerous of Polymethyl Methacrylate (PMMA) sticks in the PS 1.0 with a certain proportion. The performance of PS 2.0 was evaluated by analyzing the DFW and isocenter spot size of the modulated carbon ion beams. Finally, a plane homogeneous radiation field was simulated and fluence homogeneities were compared by using a 2D (X-Z) dose distribution and quantized by calculating the 1D-lateral flatness.ResultsCompared to the PS 1.0, the DFW is reduced by at most 1.11 mm by using PS 2.0 with a similar BP width broadening ability at the same beam range. Fluence homogeneity of PS 2.0 is excellent in all the downstream locations, and the isocenter spot size is reduced by at most 1.72 mm at the same beam range.ConclusionsThis study provides a new method for simulating the PS 2.0 as a BP broadening device with smaller DFW, better homogeneous and reduced isocenter spot size in comparison to PS 1.0.  
        关键词：Monte Carlo simulation;Scanning carbon ion beam;Porous structure;Bragg peak;Ripple filter   
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        发布时间：2024-10-25

        NUCLEAR CHEMISTRY, RADIOCHEMISTRY, RADIOPHARMACEUTICALS AND NUCLEAR MEDICINE

      • “在环境样品分析90Sr过程中，210Bi是重要干扰核素。通过分段收集淋洗液、测量并绘制淋洗曲线，发现铋、钇完全被吸附在色层柱上且二者无法完全分离，导致90Sr测量结果偏高。对于部分环境样品，210Pb-210Bi的含量远高于90Sr-90Y，必须采取进一步的除铋措施。过柱分离后残留的210Bi可以通过Bi2S3沉淀的方法去除；未进行Bi2S3沉淀除铋或除铋不完全时210Bi仍有残留。因此推荐一种利用衰变规律通过对样品源重复测量、运用公式修正的方法消除210Bi干扰。试验结果表明：210Bi与90Sr活度比≤5时，经修正后的90Sr结果与参考值的相对偏差在23%以内。环境样品通过修正方法计算的90Sr结果与Bi2S3沉淀除铋后的测量结果基本一致。”
        LI Meili,LI Qiaoqin,DENG Yuyang,QIN Lianjing,DENG Fei
        Vol. 45, Issue 5, Article number: 050301(2022) DOI: 10.11889/j.0253-3219.2022.hjs.45.050301
        摘要：Background210Bi is one of the most important interferences in the analysis of 90Sr by extractive chromatography. It is verified by the leaching curve that bismuth and yttrium are completely adsorbed on the chromatographic column in the bis(2-ethylhexyl) phosphate (HDEHP) extraction chromatography, and this two components can not be completely separated, resulting in higher measurement results of 90Sr.PurposeThis study aims to provide a modified method to eliminate 210Bi interference in the analysis of 90Sr by bis(2-ethylhexyl) phosphate (HDEHP) extraction chromatography.MethodsBy collecting the eluent, measuring the content of strontium, yttrium, lead and bismuth in the eluent and drawing the leaching curve, the adsorption and elution behavior of strontium, yttrium, lead and bismuth in the P204 resin were investigated. The residual 210Bi after column separation was experimentally removed by Bi2S3 precipitation or by measuring the sample source repeatedly and correcting the result with formulas.ResultsThe experimental results show that the relative deviation between the modified 90Sr activity and the reference value is within 23% when the activity ratio of 210Bi to 90Sr is not bigger than 5. The results of 90Sr calculated by the modified method for environmental samples are in good agreement with the measured results after bismuth removal by Bi2S3 precipitation.ConclusionsThe interference of 210Bi in the analysis of 90Sr by extractive chromatography can be eliminated by measuring the sample source repeatedly and correcting the result with formulas.  
        关键词：Strontium-90;Bismuth-210;Eliminate 210Bi interference;Extraction chromatography;Correction method   
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        发布时间：2024-10-25

        NUCLEAR PHYSICS, INTERDISCIPLINARY RESEARCH

      • “可控源替代同位素中子源进行中子孔隙度测井是核测井发展的必然趋势。为提高可控D-D源中子孔隙度测井的可行性及测量精度，分析了D-D源中子孔隙度测井中泥质影响。通过蒙特卡罗模拟，对比分析了三种源中子孔隙度测井过程中泥页岩响应；优选出D-D源的源距组合，分析了通过改变源距的方式弱化泥页岩的影响。研究表明：D-D源和241Am-Be源的泥页岩响应规律比较接近，当D-D源的源距设计相比于241Am-Be源更近即采用25~45 cm的源距组合时，D-D源中子孔隙度测井中泥页岩影响与241Am-Be源接近程度最高。虽然源距组合的改变不能使D-D源与241Am-Be源的泥页岩响应完全一致或者彻底消除泥质影响，但这种较高程度趋近为D-D源中子孔隙度测井中泥页岩校正提供了思路，也为今后测井仪器中放射源的可兼容替代有一定的应用意义。”
        ZHANG Li,HAN Xiao,YU Huawei,JIA Wenbao,GENG Xuesen
        Vol. 45, Issue 5, Article number: 050501(2022) DOI: 10.11889/j.0253-3219.2022.hjs.45.050501
        摘要：BackgroundIt is an inevitable trend in nuclear logging to use controllable source instead of isotopic neutron source for neutron porosity logging.PurposeThis study aims to improve the feasibility and measurement accuracy of controllable D-D source neutron porosity logging by analyzing, the influence of mud on D-D source neutron porosity logging.MethodsFirstly, the response of mudstone in neutron porosity logging of three sources (241Am-Be radioactive source, D-T source and D-D source) was compared and analyzed by Monte Carlo simulation method. Then, by changing the near and far source distance in D-D source neutron porosity logging, the source distance combination of D-D source was optimized to weaken the influence of shale by changing the source distance.ResultsAnalysis results show that the mudstone response characteristics of D-D source and 241Am-Be radioactive source are relatively close. When the source distance design of D-D source is closer to 241Am-Be, i.e., the source distance combination of 25~45 cm is adopted, the mudstone influence in D-D source neutron porosity logging shows the highest degree of proximity to that of 241Am-Be radioactive source.ConclusionsAlthough the change of source spacing combination can not make the mudstone response of D-D source and 241Am-Be radioactive source completely consistent or completely eliminate the influence of argillaceous matter, this high degree of convergence provides an idea for mudstone correction in D-D source neutron porosity logging and has certain application significance for the compatible substitution of radioactive sources in logging instruments in the future.  
        关键词：D-D source;241Am-Be source;Neutron porosity logging;Source distance combination;Argillaceous effect   
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      • “在半导体领域，研究人员探究了背栅偏置对PD SOI MOSFETs电参数的影响，发现背栅偏置能显著增强长沟晶体管的损伤。”
        WANG Haiyang,ZHENG Qiwen,CUI Jiangwei,LI Yudong,GUO Qi
        Vol. 45, Issue 5, Article number: 050502(2022) DOI: 10.11889/j.0253-3219.2022.hjs.45.050502
        摘要：BackgroundTotal dose effect of silicon-on-insulator (SOI) devices can be reinforced through the back gate port, hence the device parameter degradation caused by irradiation can be compensated by applying back-gate bias voltage using the positive back gate coupling effect. However, previous studies have focused more on the effects of back-gate bias voltage applied after irradiation on radiation damage, and rarely involved the regulation of back-gate bias voltage applied during irradiation on the physical process of radiation introduced into the trap charge.PurposeThis study aims to investigate the regulation and mechanism of the back gate bias on the buried oxide (BOX) radiation-induced trap charge.MethodsBased on the transistor transfer characteristic curve, the radiation damage laws of partially depleted silicon-on-insulator (PD SOI) metal oxide semiconductor field effect transistors (MOSFETs) of different sizes under different back gate biases were tested by extracting the trap charge density in the BOX layer. TCAD (Technology Computer Aided Design) device simulation was performed to investigate the mechanism of radiation damage.ResultsThe test results show that the damage of long channel transistors is significantly enhanced by applying back-gate bias during the irradiation process. When the back-gate bias is applied to short channel transistor, the distribution and intensity of electric field in BOX layer are different from that of long channel transistor, hence is affected by the source drain voltage whilst the influence of source drain voltage on long channel transistor can be ignored.ConclusionsBack gate bias and source drain voltage jointly affect the distribution and intensity of electric field in BOX layer of PD SOI MOSFETs, and the damage of long channel transistors is significantly enhanced by applying back-gate bias during the irradiation process.  
        关键词：Silicon-on-insulator;Buried oxide;Back gate control;Total ionizing dose effect   
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        发布时间：2024-10-25
      • “在物理学、化学和生物学等领域，分子碎裂动力学研究取得新进展。利用强飞秒激光脉冲诱导CO2分子解离，通过冷靶反冲离子动量谱仪测量获取离子碎片的动量信息。实验观测到CO2q+（q=2~4）4个两体解离通道，揭示动力学准直机理在所有两体碎裂通道中都占主导作用。”
        ZHANG Shuai,JIANG Wenbin,WANG Xincheng,JIANG Yuhai,ZHU Zhiyuan
        Vol. 45, Issue 5, Article number: 050503(2022) DOI: 10.11889/j.0253-3219.2022.hjs.45.050503
        摘要：BackgroundThe research of molecular fragmentation dynamics has attracted extensive attention in the fields of physics, chemistry and biology. The major challenge in this field is to understand the selectivity of molecular bond breaking and to elucidate which parameters control bond fission.PurposeThis study aims to reveal the mechanism of two and three-body fragmentation of CO2 in strong laser fields and to elucidate the dynamics information of the ion fragmentation in the Coulomb explosion.MethodsThe time-of-flight (TOF) and three-dimensional momentum distributions of ion fragments were obtained using a cold-target recoil ion momentum spectroscopy (COLTRIMS). Precise identification of the two-body and three-body dissociation channels of CO2 was determined by the photoion-photoion coincidence (PIPICO) and the photoion-photoion-photoion coincidence (PIPIPICO) techniques. The occurrence of sequential and non-sequential fragmentation during three-body dissociation was revealed by the momentum correlation between two O ions. Finally, the dynamics of the three-body fragmentation process was visualized by the Newton diagram.ResultsFour two-body dissociation channels and three three-body dissociation channels for CO2q+ (q≤4) are identified with the coincidence technique. The kinetic energy release (KER) distribution of these dissociation channels is obtained from the three-dimensional momentum.ConclusionsThe experiments reveal that the dynamic collimation mechanism plays a dominant role in the two-body fragmentation channels, and the ion fragments of the four two-body fragmentation channels are mainly emitted along the laser polarization direction with the significant anisotropic distribution. Non-sequential and sequential fragmentation of CO2 is separated and identified in the momentum correlation and Newtonian diagrams. In the first step of the sequential fragmentation of CO24+, the O2+ and CO2+ ionic fragments are always produced. It is further shown that the vibration and rotation of the CO2+ ion are shown to occur before the fragmentation of the second step.  
        关键词：Strong laser fields;Fragmentation mechanisms;Coulomb explosion;Recoil ion momentum spectroscopy   
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        发布时间：2024-10-25

        NUCLEAR ENERGY SCIENCE AND ENGINEERING

      • “在空间核动力系统领域，专家利用NSGA-II和BP神经网络算法，优化了辐射屏蔽设计，为空间堆屏蔽方案提供智能决策支持。”
        HE Can,QIU Xiaoping,SUN Zheng,SHAO Jing,CHEN Zhenping,ZHAO Pengcheng
        Vol. 45, Issue 5, Article number: 050601(2022) DOI: 10.11889/j.0253-3219.2022.hjs.45.050601
        摘要：BackgroundThe mass of a space nuclear power system is a critical parameter due to limitation of loading and high cost of transportation. The radiation shielding system is one of the main contributions of the self-weight of the space nuclear power system.PurposeThis study aims at the shielding optimization problem for the mass minimization of space nuclear power system.MethodsFirstly, the calculation model for the Topaz-II space stack was established and the shielding material was selected. Secondly, a masked multi-objective optimization model was built on the base of Non-dominated Sorting Genetic Algorithm-II (NSGA-II) to obtain an optimization scheme. Then, an intelligent decision support system for the shielding scheme to improve the optimization efficiency was established by coupling the BP neural network algorithm. Finally, the adjustment plan was obtained according to the intelligent decision support system, and verified by using Topaz-II space reactor model.ResultsVerification results show that the intelligent decision support system can be used to set up a basic theoretical model according to the actual needs of the project, and finally provide a space stack shielding scheme that meets the engineering needs.ConclusionsThe validity and feasibility of the method in this paper are proved, providing theoretical and technical support for the optimization of radiation shielding of space reactors.  
        关键词：Intelligent decision;Genetic algorithm;BP neural network;Shield optimization   
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      • “在聚变中子学分析领域，专家利用DAG-OpenMC程序，基于CAD模型，显著提高了复杂工程模型的建模与分析效率。”
        ZHONG Gangqi,XU Kun,LU Yudong,MAO Shifeng,YE Minyou
        Vol. 45, Issue 5, Article number: 050602(2022) DOI: 10.11889/j.0253-3219.2022.hjs.45.050602
        摘要：BackgroundFusion reactor engineering models are extremely complex, which makes the modeling of the neutronics analysis rather tedious and time consuming. The open-source Monte Carlo code OpenMC can directly perform particle transport simulation on CAD models by integrating DAGMC (Direct Accelerated Geometry Monte Carlo), which can significantly improve the modeling and analysis efficiency of complex engineering models.PurposeThis study aims to carry out the application research of OpenMC in fusion neutronics analysis for China Fusion Engineering Test Reactor (CFETR).MethodsBased on the CFETR 1D cylindrical shell model, the consistency of tallies of OpenMC and MCNP was verified. According to the characteristics of plasma spatial distribution, source class and source function were customized on base of the source extension interface to accurately describe the complex fusion neutron source. The 3D model of complex CFETR engineering was successfully established by using CAD geometry function of DAG-OpenMC, and the neutron wall load distribution, tritium breeding ratio (TBR) and heat were obtained.ResultsThe calculation results of DAG-OpenMC and MCNP have excellent consistency. The neutron wall load peak of CFETR appears at the mid plane, and the tritium breeding ratio of helium cooled ceramic breeder blanket is 1.141. When the fusion neutron power is 160 MW, the total nuclear heat generated is 211.73 MW, and the global energy multiplication factor is 1.32, in which the total nuclear heat generated by the blanket is 185.64 MW, accounting for 87.68% of the total nuclear heat.ConclusionsThe CAD-based geometry capabilities greatly improve the modeling efficiency of building complex fusion reactor engineering models. Verification of the key issues of DAG-OpenMC in fusion neutronics applications by this study, indicates its feasibility in dealing with fusion neutronics problems under complex engineering structural conditions.  
        关键词：Fusion neutronics;DAGMC;OpenMC;CFETR   
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      • “在熔盐堆领域，专家采用RELAP5-TMSR程序，针对误提棒ATWS事故，分析了三种停堆策略，为解决堆芯熔盐温度问题提供解决方案。”
        XU Tiangui,ZOU Yang,XU Bo,ZHU Guifeng,SUN Qiang
        Vol. 45, Issue 5, Article number: 050603(2022) DOI: 10.11889/j.0253-3219.2022.hjs.45.050603
        摘要：[Backgrounds] Among all kinds of accidents beyond the design basis of molten salt reactor (MSR), the ATWS accident of rod withdrawal is the most typical one, which is the test of the safety capability limit of the reactor. Therefore, it has important research significance in the field of accident analysis for MSR.PurposeThis study aims to assess the safety limits of the liquid MSR during postulated transients.MethodsFirst of all, the RELAP5-TMSR (reactor excursion and leak analysis program-thorium molten salt reactor) code was employed to conduct a preliminary analysis of ATWS accident of the control rod withdrawal in 125 MW liquid MSR, and the equivalent hydraulic components of this reactor were modeled. Then, the changes of key parameters such as reactor power and molten salt temperature of three shutdown strategies were analyzed. Finally, the sensitivity analysis of some important factors such as reactivity introduction value, rod lifting speed and temperature coefficient was carried out.ResultsThe shut-down strategy of keeping the primary loop pump operation, shutting down the secondary loop pump and the third loop fan keeps the lowest core molten salt temperature among the three shutdown strategies. In the case of only maintaining the operation of the primary loop pump, the temperature extremum is closely related to the reactivity introduction value, introduction rate and temperature reactivity coefficient. Thermal peak of ATWS accident of rod withdrawal increases with the increase of reactivity introduction value and rod lifting speed. Requirements for the design of regulation rod worth and temperature reactivity coefficient of MSR.ConclusionsThis study provides reference value for design requirements of regulation rod worth and temperature reactivity coefficient of MSR.  
        关键词：Molten salt reactor;ATWS;Safety analysis;RELAP-TMSR   
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      • “在熔盐高温试验领域，专家采用有限元方法对电磁感应加热进行数值模拟，为实验装置优化提供设计参考。”
        WANG Shanwu,ZHOU Chong,WANG Naxiu,ZOU Yang,CAI Chuangxiong,ZHU Haihua
        Vol. 45, Issue 5, Article number: 050604(2022) DOI: 10.11889/j.0253-3219.2022.hjs.45.050604
        摘要：BackgroundThe pebble bed heat transfer experimental facilities in the high temperature test loop of HTS (Heat Transfer Salt) molten salt is designed to study the heat transfer characteristics of molten salt and fuel pebble. The intermediate frequency induction heating is adopted to provide the internal heat source in the graphite pebble bed, which simulates the heat released by the fuel pebbles in the core of the MSRs.PurposeThis study aims to get better heating effect by analyzing the internal heat source of electromagnetic induction heating.MethodsThe finite element method was used to numerically simulate the electromagnetic induction heating of the experimental device. By analyzing the distribution of eddy current power in the experimental device under different number of graphite pebbles and coil parameters, the influence law of different design parameters on the electromagnetic induction heating performance was obtained and compared with the experimental results.ResultsThe simulation results show that the eddy current power of the graphite pebble near the edge of the coil is obviously small. When the cross-sectional area of the induction coil of the heater is 40 mm2 and the number of winding turns is 31, the heating effect can meet the experimental requirements. In the current experiment, the close distance between the metal seal structure and the coil is easy to produce eddy current power, resulting in power loss.ConclusionsThe comparison with the experimental data shows that the numerical simulation can predict the experimental results well when considering the heat leakage of the experimental device, and provide some suggestions on the optimization of the current experimental device as well as design reference for the experimental study using electromagnetic induction heating.  
        关键词：Induction heating;Finite element method;Pebble bed;Internal heat source;Convective heat transfer experiment   
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        发布时间：2024-10-25
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