The Toroidal Field (TF) coil case of the HT-7U superconducting tokamak device is made of austenitic stainless steel 316LN and is designed to operate at cryogenic temperature (4 K). 316LN can retain high strength and f...The Toroidal Field (TF) coil case of the HT-7U superconducting tokamak device is made of austenitic stainless steel 316LN and is designed to operate at cryogenic temperature (4 K). 316LN can retain high strength and fracture toughness at 4 K. Feasibility study on technical process of welding has been experimentally considered as a hopeful joint method for suppression of post-welding deformation and reduction of over-heating. Meanwhile the final range of stress intensity and the stress intensity factor (K) for pre-cracks of welding structure have been determined by using J-integral. These related results are optimistic and have shown that there's no problem in strength and fracture toughness at the vicinity of the pre-crack tip. This paper introduces the welding structure of TF coil case in detail.展开更多
In a fusion reactor, the edge localized mode（ELM） coil has a mitigating effect on the ELMs of the plasma. The coil is placed close to the plasma between the vacuum vessel and the blanket to reduce its design power a...In a fusion reactor, the edge localized mode（ELM） coil has a mitigating effect on the ELMs of the plasma. The coil is placed close to the plasma between the vacuum vessel and the blanket to reduce its design power and improve its mitigating ability. The coil works in a high-temperature,high-nuclear-heat and high-magnetic-field environment. Due to the existence of outer superconducting coils, the coil is subjected to an alternating electromagnetic force induced by its own alternating current and the outer magnetic field. The design goal for the ELM coil is to maintain its structural integrity in the multi-physical field. Taking as an example the middle ELM coil（with flexible supports） of ITER（the International Thermonuclear Fusion Reactor）, an electromagnetic–thermal–structural coupling analysis is carried out using ANSYS. The results show that the flexible supports help the three-layer casing meet the static and fatigue design requirements. The structural design of the middle ELM coil is reasonable and feasible. The work described in this paper provides the theoretical basis and method for ELM coil design.展开更多
Fiber strain sensors with robust sensing performance are indispensable for human-machine interactions in the electronic textiles.However,current fiber strain sensors are confronted with the challenges of unavoidable d...Fiber strain sensors with robust sensing performance are indispensable for human-machine interactions in the electronic textiles.However,current fiber strain sensors are confronted with the challenges of unavoidable deterioration of functional sensing components during wearable and extreme environments,resulting in unsatisfactory stability and durability.Here,we present a robust fiber strain sensor based on the mutual inductance effect.The sensor is assembled by designing coaxial helical coils around an elastic polyurethane fiber.When stretching the fiber sensor,the strain is detected by recording the voltage changes in the helical coils due to the variation in magnetic flux.The resultant fiber strain sensor shows high linearity(with a linear regression coefficient of 0.99)at a large strain of 100%,and can withstand various extreme environmental conditions,such as high/low temperatures(from-30℃to 160℃),and severe deformations,such as twisting and pressing(with a pressure of 500 N/cm).The long-term cyclic stability of our fiber strain sensor(100,000 cycles at a strain of 100%)is superior to that of most reported flexible resistive and capacitive strain sensors.Finally,the mass-produced fiber strain sensors are woven into a smart textile system to accurately capture gestures.展开更多
This article presents the design of an optimal coil structure for 2 de-tumbling devices, each is carried by a de-tumbling robot. The design is based on electromagnetic eddy current method and aims to reduce the angula...This article presents the design of an optimal coil structure for 2 de-tumbling devices, each is carried by a de-tumbling robot. The design is based on electromagnetic eddy current method and aims to reduce the angular velocity of uncooperative space targets. It proposes an optimization framework with the advantages of safety and high performance. The magnetic field analytical model is established by the designed coil’s structure parameters, and the optimal structure parameters of the coil are determined. To further ensure the maximum magnetic field at the target, the electromagnetic characteristics under different current directions in the 2 coils are analyzed based on magnetic field analytical model, and their accuracy is verified using finite element method (FEM). Additionally, an improved Maxwell’s stress tensor method is proposed to calculate the de-tumbling torque, and its accuracy is assessed using traditional Maxwell’s stress tensor and virtual displacement method. The proposed optimal coil structure and its optimization framework can de-tumble over 1 million targets of various sizes, demonstrating universality.展开更多
Purpose A capture superconducting solenoid is designed for the Experimental Muon Source(EMuS)which is proposed at China Spallation Neutron Source(CSNS)in Dongguan for muon science and neutrino physics research.The cap...Purpose A capture superconducting solenoid is designed for the Experimental Muon Source(EMuS)which is proposed at China Spallation Neutron Source(CSNS)in Dongguan for muon science and neutrino physics research.The capture superconducting solenoid of the EMuS consists of four coils with different radius generating a peak central field of 5 T at 3944 A of nominal current.Methods The aluminum-stabilized NbTi Rutherford cable is used to wind the solenoid coils.Iron yokes are arranged for flux returning and field shielding.Ti alloy Ti-6Al-4V rods are adopted to support the cold mass.The vacuum vessel of the solenoid is manufactured by 304 stainless steel.The coils are pre-stressed by interference fits assembly,the outer support cylinder or binding the coils with aluminum alloy wire in order to reduce the peak stress of the coils.The parameters of the coils such as the thickness and the tensile stress of the binding wire and the thickness of the outer support cylinder have been optimized in order to minimize the cold mass by using FEA software.Results The maximum stress in the winding is allowable with two layers of 40 mm thickness outer support cylinder through interference fits assembly.But the maximum stress in the winding is allowable with 40 mm thickness of binding wire and 30 mm thickness of outer support cylinder.Conclusion The method of binding the windings with aluminum alloy wire is suggested to be used to manufacture the solenoid.This paper presents the mechanical design and analysis of the capture superconducting solenoid for EMuS.展开更多
文摘The Toroidal Field (TF) coil case of the HT-7U superconducting tokamak device is made of austenitic stainless steel 316LN and is designed to operate at cryogenic temperature (4 K). 316LN can retain high strength and fracture toughness at 4 K. Feasibility study on technical process of welding has been experimentally considered as a hopeful joint method for suppression of post-welding deformation and reduction of over-heating. Meanwhile the final range of stress intensity and the stress intensity factor (K) for pre-cracks of welding structure have been determined by using J-integral. These related results are optimistic and have shown that there's no problem in strength and fracture toughness at the vicinity of the pre-crack tip. This paper introduces the welding structure of TF coil case in detail.
基金the Province Postdoctoral Foundation of Jiangsu(1501164B)the Technical Innovation Nurturing Foundation of Yangzhou University(2015CXJ016)China Postdoctoral Science Foundation(2016M600447)
文摘In a fusion reactor, the edge localized mode（ELM） coil has a mitigating effect on the ELMs of the plasma. The coil is placed close to the plasma between the vacuum vessel and the blanket to reduce its design power and improve its mitigating ability. The coil works in a high-temperature,high-nuclear-heat and high-magnetic-field environment. Due to the existence of outer superconducting coils, the coil is subjected to an alternating electromagnetic force induced by its own alternating current and the outer magnetic field. The design goal for the ELM coil is to maintain its structural integrity in the multi-physical field. Taking as an example the middle ELM coil（with flexible supports） of ITER（the International Thermonuclear Fusion Reactor）, an electromagnetic–thermal–structural coupling analysis is carried out using ANSYS. The results show that the flexible supports help the three-layer casing meet the static and fatigue design requirements. The structural design of the middle ELM coil is reasonable and feasible. The work described in this paper provides the theoretical basis and method for ELM coil design.
基金financially by Ministry of Science and Technology of the People's Republic of China(2022YFA1203001,2022YFA1203002)National Natural Science Foundation of China(T2321003,22335003,T2222005,22175042)Science and Technology Commission of Shanghai Municipality(21511104900).
文摘Fiber strain sensors with robust sensing performance are indispensable for human-machine interactions in the electronic textiles.However,current fiber strain sensors are confronted with the challenges of unavoidable deterioration of functional sensing components during wearable and extreme environments,resulting in unsatisfactory stability and durability.Here,we present a robust fiber strain sensor based on the mutual inductance effect.The sensor is assembled by designing coaxial helical coils around an elastic polyurethane fiber.When stretching the fiber sensor,the strain is detected by recording the voltage changes in the helical coils due to the variation in magnetic flux.The resultant fiber strain sensor shows high linearity(with a linear regression coefficient of 0.99)at a large strain of 100%,and can withstand various extreme environmental conditions,such as high/low temperatures(from-30℃to 160℃),and severe deformations,such as twisting and pressing(with a pressure of 500 N/cm).The long-term cyclic stability of our fiber strain sensor(100,000 cycles at a strain of 100%)is superior to that of most reported flexible resistive and capacitive strain sensors.Finally,the mass-produced fiber strain sensors are woven into a smart textile system to accurately capture gestures.
基金supported by the National Natural Science Foundation of China(11972078).
文摘This article presents the design of an optimal coil structure for 2 de-tumbling devices, each is carried by a de-tumbling robot. The design is based on electromagnetic eddy current method and aims to reduce the angular velocity of uncooperative space targets. It proposes an optimization framework with the advantages of safety and high performance. The magnetic field analytical model is established by the designed coil’s structure parameters, and the optimal structure parameters of the coil are determined. To further ensure the maximum magnetic field at the target, the electromagnetic characteristics under different current directions in the 2 coils are analyzed based on magnetic field analytical model, and their accuracy is verified using finite element method (FEM). Additionally, an improved Maxwell’s stress tensor method is proposed to calculate the de-tumbling torque, and its accuracy is assessed using traditional Maxwell’s stress tensor and virtual displacement method. The proposed optimal coil structure and its optimization framework can de-tumble over 1 million targets of various sizes, demonstrating universality.
基金National Natural Science Foundation of China(Project:11527811).
文摘Purpose A capture superconducting solenoid is designed for the Experimental Muon Source(EMuS)which is proposed at China Spallation Neutron Source(CSNS)in Dongguan for muon science and neutrino physics research.The capture superconducting solenoid of the EMuS consists of four coils with different radius generating a peak central field of 5 T at 3944 A of nominal current.Methods The aluminum-stabilized NbTi Rutherford cable is used to wind the solenoid coils.Iron yokes are arranged for flux returning and field shielding.Ti alloy Ti-6Al-4V rods are adopted to support the cold mass.The vacuum vessel of the solenoid is manufactured by 304 stainless steel.The coils are pre-stressed by interference fits assembly,the outer support cylinder or binding the coils with aluminum alloy wire in order to reduce the peak stress of the coils.The parameters of the coils such as the thickness and the tensile stress of the binding wire and the thickness of the outer support cylinder have been optimized in order to minimize the cold mass by using FEA software.Results The maximum stress in the winding is allowable with two layers of 40 mm thickness outer support cylinder through interference fits assembly.But the maximum stress in the winding is allowable with 40 mm thickness of binding wire and 30 mm thickness of outer support cylinder.Conclusion The method of binding the windings with aluminum alloy wire is suggested to be used to manufacture the solenoid.This paper presents the mechanical design and analysis of the capture superconducting solenoid for EMuS.
