文中基于超导磁通动力学理论,考虑电磁力与热激活对磁通运动的影响,基本模型包括由等效电阻率随超导体温度和磁场变化的磁通扩散方程,以及比热随超导体温度变化的热传导方程组成.在此基础上,用数值方法求解了这组非线性磁热耦合方程,主要研究了有磁通跳跃状发生状态时环境温度和外磁场速度对于高温超导磁致伸缩的影响.结果表明:磁通进入超导体时超导体收缩,磁通退出超导体时超导体伸长,当有磁通跳跃发生时在一个加载周期内超导体最大伸长量与收缩量近似相等,而没有磁通跳跃时最大收缩量几乎是最大伸长量的两倍.如同对于磁通跳跃的影响外加磁场速度、环境温度对于超导磁致伸缩有明显的影响.%Based on the superconducting flux dynamical theory with considering thermal activate and electromagnet force, the fundamental model was composed of magnetic diffusion equation, which the equivalent resistivity varied with the temperature and magnetic flux in the superconductor, and heat conductance equation, which the specific heat varied with the temperature in the superconductor. The nonlinear equations of magnetothermal couple were resolved in the method of finite difference. The results show the superconductor is shrinked when magnetic flux enters it, and the superconductor is stretched when magnetic flux exits. In a period of applied magnetic field, the maximum value of shrink is about equal to the maximum value of elongation in the process of flux jump, while the former is twice the latter in the process of no flux jump. Sweep rates of applied magnetic field and ambient temperature play an important role for magnetostriction of superconductor the same as for flux jump.
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