Analysis of torque in nested magnetic cylinders
Analysis of torque in nested magnetic cylinders
复制标题
DOI：
10.1063/1.371705
复制
发表时间：
1999-12-01
影响因子：
3.2
通讯作者：
Coey, JMD
中科院分区：
文献类型：
--
作者：
Ní Mhíocháin, TR;Weaire, D;Coey, JMD
可旋转的嵌套圆柱形磁体可用于产生可变磁场。在实际设计中，气缸之间存在相互扭矩，这是一个重要的考虑因素。我们提出了一个彻底的调查，这种扭矩，结合实验，计算和理论。在有限长度的情况下，其中磁化根据Halbach的处方变化，扭矩是端部效应。它与sin alpha成比例，其中alpha是定义圆柱体相对方向的角度。实际设计使用离散数量N的永磁体段来近似理想设计的连续变化的磁化。这些将更高分量sin（n alpha）引入扭矩的角度依赖性，其中根据分段磁体扭矩定理，n的允许值被限制为n =（kN +/- 1）。(C)1999年美国物理学会。[S0021-8979（99）06122-8]。
Rotatable nested cylindrical magnets may be used to generate variable magnetic fields. A mutual torque exists between the cylinders which is an important consideration in practical designs. We present a thorough investigation of this torque, combining experiment, computation, and theory. In the finite length case, in which the magnetization varies according to the prescription of Halbach, the torque is an end effect. It is proportional to sin alpha, where alpha is the angle defining the relative orientation of the cylinders. Practical designs use a discrete number N of permanent magnet segments to approximate the continuously varying magnetization of the ideal design. These introduce higher components sin(n alpha) to the angular dependence of torque, where the allowed values of n are restricted to n = (kN +/- 1) according to the segmented magnet torque theorem. (C) 1999 American Institute of Physics. [S0021-8979(99)06122-8].