The development of stellarators that use permanent magnet arrays to shape their confining magnetic fields has been a topic of recent interest, but the requirements for how such magnets must be shaped, manufactured, and assembled remain to be determined. To address these open questions, we have performed a study of geometric concepts for magnet arrays with the aid of the newly developed MAGPIE code. A proposed experiment similar to the National Compact Stellarator Experiment (NCSX) is used as a test case. Two classes of magnet geometry are explored: curved bricks that conform to a regular grid in cylindrical coordinates, and hexahedra that conform to the toroidal plasma geometry. In addition, we test constraints on the magnet polarization. While magnet configurations constrained to be polarized normally to a toroidal surface around the plasma are unable to meet the required magnetic field parameters when subject to physical limitations on the strength of present-day magnets, configurations with unconstrained polarizations are shown to satisfy the physics requirements for a targeted plasma.

中文翻译：

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仿星器永磁阵列的几何概念

使用永磁体阵列来塑造其封闭磁场的仿星器的开发一直是最近感兴趣的话题，但对如何塑造、制造和组装此类磁铁的要求仍有待确定。为了解决这些悬而未决的问题，我们借助新开发的 MAGPIE 代码对磁体阵列的几何概念进行了研究。一个类似于国家紧凑型仿星器实验 (NCSX) 的拟议实验被用作测试案例。探索了两类磁体几何形状：符合圆柱坐标中规则网格的弯曲砖和符合环形等离子体几何形状的六面体。此外，我们测试了磁极化的约束。