知识与财富的链接
阐述了 Halbach 永磁阵列的原理及所产生的静磁场的特点,利用 Maxwell 仿真软件对一种可用于核磁共振小型化的圆柱型 Halbach 阵列进行了静磁场仿真分析--首先对理想情况下圆柱型 Halbach 阵列在不同离散磁块数、磁性材料和磁块尺寸时所产生的磁感应强度进行了对比,然后将充磁方向和磁块性能存在误差的非理想情况与理想情况下的 Halbach 阵列产生的静磁场进行了对比,最后将 Halbach 阵列与 H 型常规永磁体进行了对比．结果表明:组成 Halbach 阵列的磁块数目、磁性材料的性能和磁块尺寸是影响磁感应强度的主要因素;磁块选材、充磁等加工工艺对 Halbach 阵列的磁场均匀性有很重要的影响;相比于常规永磁体,Halbach 阵列在用料和产生的磁场强度方面具有一定的优势．
This paper describes the principle of permanent magnetic Halbach array and the features of the corre-sponding static magnetic field,and numerically analyzes the static magnetic field of a miniaturized cylindrical Hal-bach array using for nuclear magnetic resonance with the Maxwell software.First,comparative analysis is conductedfor the magnetic induction intensities of the cylindrical Halbach array under ideal conditions with different parame-ters,such as the number of discrete magnetic blocks,the type of magnetic material and the size of magnetic blocks.Then,a comparison of the results in ideal conditions is made with those in non- ideal conditions with a magnetizationdirection error or a magnetic property error of magnetic block.Finally,a comparison is also made between Halbacharray and the conventional H- style permanent magnet.The results show that (1) the number of magnetic blocks,the magnetic material and the size of magnetic blocks are the main factors affecting the magnetic induction intensityof Halbach array; (2) the manufacturing technology,such as the selection of magnetic blocks and the magnetiza-tion,significantly affects the homogeneity of magnetic field; and (3) Halbach array is superior to the conventionalpermanent magnet in terms of material adoption and generated magnetic induction intensity.