High temperature superconducting magnetic suspension and three-dimensional numerical study of theoretical models

　　Title: High temperature superconducting magnetic suspension and three-dimensional numerical study of theoretical models
　　Author: Ma light with
　　Degree-granting units: Southwest Jiaotong University
　　Keywords: high-temperature superconductors;; maglev;; three-dimensional theoretical model;; finite element;; preconditioned conjugate gradient Neodymium Magnets method
　　Abstract:
　　Although the theoretical study of high-temperature superconducting Maglev has exceeded two-dimensional or axisymmetric situations limitations, and gradually to more realistic
　　Move closer to the three-dimensional case, but the current three-dimensional theoretical model or ignore the electromagnetic anisotropy of high-temperature superconductors or too simple for its
　　Treatment, resulting in high-temperature superconductors on the electromagnetic properties of the model description is not enough. Therefore, the theoretical study of high-temperature superconducting maglev has yet to be further
　　Further improved.
　　In this paper, Maxwell's equations and high-temperature superconductor resistivity anisotropy, combined with high-temperature superconductors of electricity
　　Magnetic constitutive relation to vector potential as state variable, set up to consider the phenomenon of high temperature superconductor electrical anisotropic three-dimensional electromagnetic field equations
　　. State of motion for the study of the thermal high-temperature superconductors under magnetic coupling, high-temperature superconductors are http://www.everbeenmagnet.com/en/products/110-sintered-neodymium-magnets given control of the temperature field equation. In the real value
　　Current methods, respectively, using Galerkin finite element and Crank-Nicolson-θ finite difference spatial discretization of the equations and
　　Discrete time. In addition, the magnetic track to simulate the gap between the adjacent permanent magnet field caused by the inhomogeneity along the vertical, the use of terrestrial
　　Flow model to establish a permanent magnetic field of three-dimensional analytical model of the track.
　　In the model validation, a detailed comparison of different discussions
　　Sport mode the numerical results and experimental test results, including the vertical movement under the specific field of translation symmetry zero-field cooling, field cooling hanging
　　Three cases with the suspension and floating axisymmetric field in zero field cooling conditions; lateral movement end cold suspension, suspension height is equal to field-cooling height and overhang
　　Linked to three cases; vertical suspension movement under power relationship with changes in exercise time. The results show that the proposed three-dimensional theoretical model can be
　　Better reflect the high-temperature superconductors and the electromagnetic force field. On this basis, the theoretical study of the three-dimensional movement of bulk materials under high-temperature superconducting magnetic
　　Suspension characteristics.
　　For vertical movement, an analysis of working conditions, field structure, material properties and geometry and other effects due to
　　Prime role of the law of levitation force, then discussed the levitation force relaxation characteristics and factors affecting the role of law, improve the bulk of the material obtained
　　Material performance or lower the temperature, can significantly increase the levitation force, but also can effectively suppress or even avoid the conclusion levitation force relaxation decay, and finally from the manager
　　On pre-loaded on the confirmed suspension force can effectively inhibit the relaxation decay, is to improve the stability of the system is an effective means of suspension.
　　For lateral movement, an analysis of working conditions, the maximum horizontal displacement, material properties and geometry and other factors on the electromagnetic force
　　Role of the law, then discussed the critical field of high-temperature superconductors cold height issue, found that with the suspension height increases, the improvement of material properties
　　Or temperature decreases, the critical field-cooling height is gradually reduced, and subsequent suspension for the study of the minimum horizontal feature can restore
　　Method, and finally the process of continuous lateral movement under different conditions with the levitation and guidance force variation of the number of lateral movement had deep
　　Into the analysis, and confirmed the pre-set theory can effectively suppress the lateral movement caused by the levitation force decay.
　　For vertical movement,
　　Into magnetic levitation rail launch and two applications. Maglev launch applications on the study include the track gap,
　　Exit velocity and temperature of the levitation force of law and the different exit velocity and temperature of the maximum temperature rise within the bulk of variation; on track
　　Road traffic applications, the effects of different field-cooling height, suspension height, velocity and temperature during exercise in the suspension force change rules
　　Law, analyzed the velocity and temperature on the maximum temperature rise within the bulk of law. The results show that, for any kind of application, reduced
　　Low bulk temperature, can restrain the levitation force decay and reduce the role of temperature. In addition, the study also found that the resistance floating suspension than
　　Small, this high-temperature superconducting maglev technology in the field of high speed is very favorable.
　　Degree Year: 2009