基于OPERA/QUENCH的MRI超导对称与非对称磁体失超特性对比(英文)  

COMPARISON OF QUENCH CHARACTERISTICS For MRI SUPERCONDUCTING MAGNETS BETWEEN SYMMETRIC AND ASYMMETRIC CONFIGURATIONS USING OPERA/QUENCH

作　　者：张冉[1] 杨立欣[2] 陈凯[1] 孔德平[3] 朱贵友[2] 

机构地区：[1]中石化胜利油田技术检测中心,山东东营257000 [2]中石化胜利油田滨南采油厂,山东滨州256600 [3]滨州学院电气工程系,山东滨州256600

出　　处：《低温物理学报》2014年第5期359-368,共10页Low Temperature Physical Letters

摘　　要：在MRI磁体的设计过程中,失超现象的研究对于超导磁体的安全运行具有重要的意义.本文采用三维有限元软件OPERA分别对1T对称磁体和非对称磁体的失超特性进行了仿真分析.详细介绍了仿真的建模过程和求解算法.NbTi超导材料的临界电流密度通过软件预设的查表变量实现设置.通过仿真分析,得到了两种磁体结构在失超过程中重要的物理量如超导线圈的电流、电阻的变化规律.三维仿真图形更有利于观察失超在不同方向的传播速度.通过比较得出结论,虽然对非称磁体的DSV比对称磁体要大,但在失超过程中,非对称磁体受到的破坏也比对称磁体要严重.The analysis of quench behavior becomes more necessary in design of modern clinic magnetic resonance imaging （MRI） superconducting magnets for safety operation. In this study, a commercial three dimension FEM software OPERA-3D/QUENCH is employed to address the quench characteristics of 1T MRI magnets with both symmetric and asymmetric configurations. The modeling process and setup for the solving are discussed in detail. Critical current density of NbTi superconducting material is implemented by utilizing an enhanced table variable pre- determined. Important physical quantities such as current and resistance of superconducting coils during the transition for two designs are provided comparatively. An intuitive 3D view of instantaneous temperature distribution offers a better understanding of quench propagation velocity （QPV） in longitude and transverse direction. By comparing the correspondent simulation results, it is concluded that the MRI magnets with asymmetric art will endure more damage during the quench although it has the diameter spherical volume （DSV） closer to end of magnets than the symmetric design.

关 键 词：MRI超导磁体 失超特性 对称磁体 非对称磁体 

分 类 号：O511[理学—低温物理]