A set of four in-vessel saddle coils was designed to generate a helical field on the J- TEXT tokamak to study the influences of the external perturbation field on plasma. The coils are fed with alternating current up ...A set of four in-vessel saddle coils was designed to generate a helical field on the J- TEXT tokamak to study the influences of the external perturbation field on plasma. The coils are fed with alternating current up to 10 kA at frequency up to 10 kHz. Due to the special structure, complex thermal environment and limited space in the vacuum chamber, Jt is very important to make sure that the coils will not be damaged when undergoing the huge electromagnetic forces in the strong toroidal field, and that their temperatures don＇t rise too much and destroy the in- sulation. A 3D finite element model is developed in this paper using the ANSYS code, stresses are analyzed to find the worst condition, and a mounting method is then established. The results of the stress and modal analyses show that the mounting method meets the strength requirements. Finally, a thermal analysis is performed to study the cooling process and the temperature distribution of the coils.展开更多
Multifunctional metastructure integrated broadband microwave absorption and effective mechanical resistance has attracted much attention.However,multifunctional performance is limited by the lack of theoretical approa...Multifunctional metastructure integrated broadband microwave absorption and effective mechanical resistance has attracted much attention.However,multifunctional performance is limited by the lack of theoretical approaches to integrated design.Herein,a multi-layer impedance gradient honeycomb(MIGH)was designed through theoretical analysis and simulation calculation,and fabricated using 3D printing technique.A theoretical calculation strategy for impedance gradient structure was established based on the electromagnetic parameter equivalent method and the multi-layer finite iterative method.The impedance of MIGH was analyzed by the theoretical calculation strategy to resolve the broadband absorption.Intrinsic loss mechanism of matrix materials and distributions of electric fields,magnetic fields and power loss were analyzed to investigate the absorption mechanism.Experimental results indicated that a 15 mm thick designed metastructure can achieve the absorption more than 88.9%in the frequency range of 2-18 GHz.Moreover,equivalent mechanical parameters of MIGH was calculated by integral method according to the Y-shaped model.Finite Element analysis of stress distributions were carried out to predict the deformation behavior.Mechanical tests demonstrate that MIGH achieved the compression modulus of 22.89 MPa and flexure modulus of 17.05 MPa.The integration of broadband electromagnetic absorption and effective mechanical resistance was achieved by the proposed design principle and fabrication methodology.展开更多
基金supported by the ITER Project Funds of China (No.2010GB107004)National Natural Science Funds of China (No.50907029)
文摘A set of four in-vessel saddle coils was designed to generate a helical field on the J- TEXT tokamak to study the influences of the external perturbation field on plasma. The coils are fed with alternating current up to 10 kA at frequency up to 10 kHz. Due to the special structure, complex thermal environment and limited space in the vacuum chamber, Jt is very important to make sure that the coils will not be damaged when undergoing the huge electromagnetic forces in the strong toroidal field, and that their temperatures don＇t rise too much and destroy the in- sulation. A 3D finite element model is developed in this paper using the ANSYS code, stresses are analyzed to find the worst condition, and a mounting method is then established. The results of the stress and modal analyses show that the mounting method meets the strength requirements. Finally, a thermal analysis is performed to study the cooling process and the temperature distribution of the coils.
基金supported by the National Natural Science Foundation of China(Grant No.62201352)。
文摘Multifunctional metastructure integrated broadband microwave absorption and effective mechanical resistance has attracted much attention.However,multifunctional performance is limited by the lack of theoretical approaches to integrated design.Herein,a multi-layer impedance gradient honeycomb(MIGH)was designed through theoretical analysis and simulation calculation,and fabricated using 3D printing technique.A theoretical calculation strategy for impedance gradient structure was established based on the electromagnetic parameter equivalent method and the multi-layer finite iterative method.The impedance of MIGH was analyzed by the theoretical calculation strategy to resolve the broadband absorption.Intrinsic loss mechanism of matrix materials and distributions of electric fields,magnetic fields and power loss were analyzed to investigate the absorption mechanism.Experimental results indicated that a 15 mm thick designed metastructure can achieve the absorption more than 88.9%in the frequency range of 2-18 GHz.Moreover,equivalent mechanical parameters of MIGH was calculated by integral method according to the Y-shaped model.Finite Element analysis of stress distributions were carried out to predict the deformation behavior.Mechanical tests demonstrate that MIGH achieved the compression modulus of 22.89 MPa and flexure modulus of 17.05 MPa.The integration of broadband electromagnetic absorption and effective mechanical resistance was achieved by the proposed design principle and fabrication methodology.
