The dynamic biaxial compression test for carbon-fiber-reinforced polymer(CFRP)laminates was carried out via synchronous electromagnetic loading in this study.During the experiments,four stress pulses transmitted along...The dynamic biaxial compression test for carbon-fiber-reinforced polymer(CFRP)laminates was carried out via synchronous electromagnetic loading in this study.During the experiments,four stress pulses transmitted along four incident bars,loading the square specimen simultaneously from four directions to keep the center of the specimen still.The dynamic mechanical behavior of CFRP was obtained employing the one-dimensional wave propagation theory,and the deformation and failure processes of the specimens were recorded by a high-speed camera.The effects of various biaxial stresses on the compressive strength were investigated in three biaxial and one uniaxial loading cases.For the CFRP laminates,the dynamic transverse compressive stress showed little effect on the longitudinal ultimate compressive strength.Numerical simulations were performed to understand the dynamic stress wave propagation.It showed that the employed loading device could guarantee good biaxial loading conditions until the ultimate failure of the specimens.This approach allows for the dynamic biaxial compression testing of various materials,which is of great significance in evaluating the dynamic impact performance of aeronautical composites.展开更多
For a robust design of vacuum vessel of HL-2M, the electromagnetic （EM） loads have to be understood clearly. In this paper, some crucial transient events, such as plasma major disruptions （MDs）, vertical displacem...For a robust design of vacuum vessel of HL-2M, the electromagnetic （EM） loads have to be understood clearly. In this paper, some crucial transient events, such as plasma major disruptions （MDs）, vertical displacement events （VDEs）, fast discharge of toroidal field （TF） coils, have been investigated to evaluate the eddy currents and EM forces on vacuum vessel and in-vessel components. The results show that the eddy currents depend strongly on the current decay time, and the maximum toroidal eddy current flowing in the whole vessel can reach up to 2.4 MA during MDs that is close to the plasma current. Large symmetric radial forces and a net vertical force on vessel shells could be caused by these transient events. Combination of eddy currents in in-vessel components and toroidal field could twist the copper plates and other internal parts, however, if these plates are supported and connected carefully, the twist moments will not have a big effect on the vessel shells and vessel support.展开更多
A promising way to realize controlled nuclear fusion involves the use of magnetic fields to control and confine the hot plasma configuration.This approach requires superconductor magnets operating above 15 T for the n...A promising way to realize controlled nuclear fusion involves the use of magnetic fields to control and confine the hot plasma configuration.This approach requires superconductor magnets operating above 15 T for the next generation of fusion devices.Due to their high in-field transport current capacity,rare-Earth barium copper oxide(REBCO)coated conductors are promising materials for manufacturing of cable-in-conduit conductors(CICCs)for fusion.However,the high-aspect-ratio geometry makes it difficult to find a multi-tape CICC configuration that fulfills the high engineering current density requirements while retaining enough flexibility for winding large-scale magnets.Moreover,the multilayer structure and inherent brittleness make the REBCO tapes susceptible to degradation during CICC manufacturing and operation.For more than a decade,the development of a reliable REBCO-based CICC that can sustain the huge combined mechanical,thermal,and Lorentz loads without degradation has been ongoing,albeit with limited progress.In this paper,we report on a prototype REBCO CICC that can withstand an applied cyclic Lorentz load of at least 830 kN·m^(-1),corresponding to a transport current of 80 kA at 10.85 T and 4.5 K.To our knowledge,this is the highest load achieved to date.The CICC uses 288 tapes wound into six strengthened sub-cables,making it capable of having a current sharing temperature,Tcs,of around 39 and 20 K when operated under 10.85 T with a current of 40 and 80 kA,respectively.Scaled to a 20-T peak field and 46.5-kA transport current,this provides a temperature margin of over 10 K with respect to an operating temperature of 4.5 K.In addition,no perceptible transport current performance degradation was observed after cyclic Lorentz loading,cyclic warm-up/cool-down(WUCD),and quench campaigns.The proposed REBCO CICC is a milestone in the development of high-temperature superconductors for large-scale and high-field magnet applications.展开更多
Analysis of the electromagneto-mechanical coupling effect contributes greatly to the high accuracy estimation of the EM load of many EM devices, such as a tokamak structure during plasma disruption. This paper present...Analysis of the electromagneto-mechanical coupling effect contributes greatly to the high accuracy estimation of the EM load of many EM devices, such as a tokamak structure during plasma disruption. This paper presents a method for the numerical analysis of the electromagnetomechanical coupling effect on the basis of Maxwell＇s equations in the Lagrangian description and staggered load transfer scheme, which can treat the coupled behaviors of magnetic damping and magnetic stiffness effects at the same time. Codes were developed based on the ANSYS development platform and were applied to solve two typical numerical examples： the TEAM Problem 16 and dynamic behavior analysis of a shallow arch under electromagnetic force. The good consistency of numerical results and experimental data demonstrates the validity and accuracy of the proposed method and the related numerical codes.展开更多
The structural design of equatorial diagnostic port plug for international thermonuclear experimental reactor （ITER） was discussed in this paper. The induced electromagnetic （EM） loads of port plug and blanket shi...The structural design of equatorial diagnostic port plug for international thermonuclear experimental reactor （ITER） was discussed in this paper. The induced electromagnetic （EM） loads of port plug and blanket shielding module （BSM） were presented. The finite element analysis （FEA） and numerical calculation of the system were performed under the maximum loads. According to the American Society of Mechanical Engineers （ASME） criteria, the EM stress is far below the admissible failure boundary, which indicates that the system can resist the cooperative action of EM loads and device deadweight. The analysis could provide technical data and references for further analysis and optimized design of the system.展开更多
A study on a 4-stage sub-size MgB_(2) Cable-in-Conduit Conductor(CICC),tested at the Institute of Plasma Physics,Chinese Academy of Sciences(ASIPP),revealed a 20%degradation in critical current at 4.2 K compared to si...A study on a 4-stage sub-size MgB_(2) Cable-in-Conduit Conductor(CICC),tested at the Institute of Plasma Physics,Chinese Academy of Sciences(ASIPP),revealed a 20%degradation in critical current at 4.2 K compared to single-strand data.To address this issue,the mechanical properties of MgB_(2) wires from Hyper Tech and WST were investigated,and two sub-size CICCs were manufactured using a“close-to-1-ratio”Twente design with smaller diameter wires.These cables demonstrated no significant degradation in critical current after cabling and compaction,nor after electromagnetic load cycling.The results indicate that the closeto-1-ratio cable design is optimal for brittle superconducting materials such as MgB_(2),Nb3Sn,and BSCCO,as it minimizes mechanical stress and preserves superconducting properties.This design shows significant potential for the application of MgB_(2) in next-generation fusion reactors,particularly in Poloidal Field(PF)coils,Correction Coils(CC),and feeders.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11527803 and 12072289)the Science Challenge Project(No.TZ2018001)the 111 Project(No.BP0719007).
文摘The dynamic biaxial compression test for carbon-fiber-reinforced polymer(CFRP)laminates was carried out via synchronous electromagnetic loading in this study.During the experiments,four stress pulses transmitted along four incident bars,loading the square specimen simultaneously from four directions to keep the center of the specimen still.The dynamic mechanical behavior of CFRP was obtained employing the one-dimensional wave propagation theory,and the deformation and failure processes of the specimens were recorded by a high-speed camera.The effects of various biaxial stresses on the compressive strength were investigated in three biaxial and one uniaxial loading cases.For the CFRP laminates,the dynamic transverse compressive stress showed little effect on the longitudinal ultimate compressive strength.Numerical simulations were performed to understand the dynamic stress wave propagation.It showed that the employed loading device could guarantee good biaxial loading conditions until the ultimate failure of the specimens.This approach allows for the dynamic biaxial compression testing of various materials,which is of great significance in evaluating the dynamic impact performance of aeronautical composites.
文摘For a robust design of vacuum vessel of HL-2M, the electromagnetic （EM） loads have to be understood clearly. In this paper, some crucial transient events, such as plasma major disruptions （MDs）, vertical displacement events （VDEs）, fast discharge of toroidal field （TF） coils, have been investigated to evaluate the eddy currents and EM forces on vacuum vessel and in-vessel components. The results show that the eddy currents depend strongly on the current decay time, and the maximum toroidal eddy current flowing in the whole vessel can reach up to 2.4 MA during MDs that is close to the plasma current. Large symmetric radial forces and a net vertical force on vessel shells could be caused by these transient events. Combination of eddy currents in in-vessel components and toroidal field could twist the copper plates and other internal parts, however, if these plates are supported and connected carefully, the twist moments will not have a big effect on the vessel shells and vessel support.
基金supported by the Comprehensive Research Facility for the Fusion Technology Program of China(2018-000052-73-01-001228)the National Key Research and Development Program of China(2022YFE03150200)+3 种基金the Institute of Energy,Hefei Comprehensive National Science Center(21KZS207)the National Natural Science Foundation of China(52077212)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2021444)the European–China collaboration program on the FUSION magnet.
文摘A promising way to realize controlled nuclear fusion involves the use of magnetic fields to control and confine the hot plasma configuration.This approach requires superconductor magnets operating above 15 T for the next generation of fusion devices.Due to their high in-field transport current capacity,rare-Earth barium copper oxide(REBCO)coated conductors are promising materials for manufacturing of cable-in-conduit conductors(CICCs)for fusion.However,the high-aspect-ratio geometry makes it difficult to find a multi-tape CICC configuration that fulfills the high engineering current density requirements while retaining enough flexibility for winding large-scale magnets.Moreover,the multilayer structure and inherent brittleness make the REBCO tapes susceptible to degradation during CICC manufacturing and operation.For more than a decade,the development of a reliable REBCO-based CICC that can sustain the huge combined mechanical,thermal,and Lorentz loads without degradation has been ongoing,albeit with limited progress.In this paper,we report on a prototype REBCO CICC that can withstand an applied cyclic Lorentz load of at least 830 kN·m^(-1),corresponding to a transport current of 80 kA at 10.85 T and 4.5 K.To our knowledge,this is the highest load achieved to date.The CICC uses 288 tapes wound into six strengthened sub-cables,making it capable of having a current sharing temperature,Tcs,of around 39 and 20 K when operated under 10.85 T with a current of 40 and 80 kA,respectively.Scaled to a 20-T peak field and 46.5-kA transport current,this provides a temperature margin of over 10 K with respect to an operating temperature of 4.5 K.In addition,no perceptible transport current performance degradation was observed after cyclic Lorentz loading,cyclic warm-up/cool-down(WUCD),and quench campaigns.The proposed REBCO CICC is a milestone in the development of high-temperature superconductors for large-scale and high-field magnet applications.
基金supported by National Magnetic Confinement Fusion Program of China(No.2013GB113005)the National Natural Science Foundation of China(Nos.51277139,11321062)the National 973 Program of China(No.2011CB610303)
文摘Analysis of the electromagneto-mechanical coupling effect contributes greatly to the high accuracy estimation of the EM load of many EM devices, such as a tokamak structure during plasma disruption. This paper presents a method for the numerical analysis of the electromagnetomechanical coupling effect on the basis of Maxwell＇s equations in the Lagrangian description and staggered load transfer scheme, which can treat the coupled behaviors of magnetic damping and magnetic stiffness effects at the same time. Codes were developed based on the ANSYS development platform and were applied to solve two typical numerical examples： the TEAM Problem 16 and dynamic behavior analysis of a shallow arch under electromagnetic force. The good consistency of numerical results and experimental data demonstrates the validity and accuracy of the proposed method and the related numerical codes.
文摘The structural design of equatorial diagnostic port plug for international thermonuclear experimental reactor （ITER） was discussed in this paper. The induced electromagnetic （EM） loads of port plug and blanket shielding module （BSM） were presented. The finite element analysis （FEA） and numerical calculation of the system were performed under the maximum loads. According to the American Society of Mechanical Engineers （ASME） criteria, the EM stress is far below the admissible failure boundary, which indicates that the system can resist the cooperative action of EM loads and device deadweight. The analysis could provide technical data and references for further analysis and optimized design of the system.
基金supported by the National Natural Science Foundation of China(Grant No.52207035)the“Hundred Talents Program”of the Chinese Academy of Sciences(Grant No.2022000625).
文摘A study on a 4-stage sub-size MgB_(2) Cable-in-Conduit Conductor(CICC),tested at the Institute of Plasma Physics,Chinese Academy of Sciences(ASIPP),revealed a 20%degradation in critical current at 4.2 K compared to single-strand data.To address this issue,the mechanical properties of MgB_(2) wires from Hyper Tech and WST were investigated,and two sub-size CICCs were manufactured using a“close-to-1-ratio”Twente design with smaller diameter wires.These cables demonstrated no significant degradation in critical current after cabling and compaction,nor after electromagnetic load cycling.The results indicate that the closeto-1-ratio cable design is optimal for brittle superconducting materials such as MgB_(2),Nb3Sn,and BSCCO,as it minimizes mechanical stress and preserves superconducting properties.This design shows significant potential for the application of MgB_(2) in next-generation fusion reactors,particularly in Poloidal Field(PF)coils,Correction Coils(CC),and feeders.
