| The factors of affecting the stability of superconducting magnets include:the complex operating environment, such as low temperature, high magnetic field, and the complex structure of the superconducting magnet, such as metal base of magnet, protective circuit system, frame of magnet, paraffin wax, epoxy resin and so on, which all have complex compositions and quite different physical and mechanical properties. In a strong magnetic field, the critical current of the superconducting magnet has the phenomenon of degradation. The higher the external magnetic field is, the more reduction of the critical current density of magnet is. The analysis of the magnetic field’s influence on the quench process of the superconducting coils has is of great significance to the design and safe operation of the superconducting magnet.For the high temperature superconducting coil, we established a two-dimensional numerical model based on the multi-physical-field software COMSOL to analyze the characteristics of heat transfer and temperature field distribution during the quench process of a superconducting coil under an applied magnetic field. The paper firstly focused on the influence of the different external magnetic field on heat transfer during the quench process of the superconducting structure, and the results showed that the greater the magnetic field is applied, the faster the temperature change rises. Considering the difference of magnetic-field distribution internal and external the superconducting coil and the magnet flux penetration on the quench, we further analyzed the heat conduction and the distribution of the temperature field in the superconducting winding coil. It was shown that the inhomogeneous distribution inside the superconducting winding coil significantly affects the location of the maximum temperature during the quench process, and the related results are agreed with the existing experimental observations. |
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