Center for High Field MRI, Radiology, Leiden University Medical Center, Leiden, The Netherlands.
Sci Rep. 2023 Feb 16;13(1):2774. doi: 10.1038/s41598-023-29533-9.
Does the Halbach magnetization rotation rule that is used for designing circular magnet arrays for achieving the best homogeneity hold also for an elliptical or other non-circular cross-section? In this article, it is shown that a new numerically optimized magnetization rotation rule can provide more than three orders of magnitude improvement in field homogeneity as compared to a Halbach configuration for elliptical systems. Further it is demonstrated that such optimized magnetization rules can be easily derived in an intuitive way by studying virtual permanent magnets of a similar cross-section as the desired magnet array. This is coined as a permanent magnet hypothesis. Finally, it is shown that the applicability of this technique is not limited to circular or elliptical systems but can be applied to any arbitrarily shaped cross-section.
对于设计用于实现最佳均匀度的圆形磁体阵列，所使用的哈巴赫磁化旋转规则是否也适用于椭圆形或其他非圆形横截面？本文表明，对于椭圆形系统，与哈巴赫配置相比，新的数值优化磁化旋转规则可以将磁场均匀度提高三个数量级以上。进一步表明，可以通过研究与所需磁体阵列具有相似横截面的虚拟永磁体，以直观的方式轻松推导出这种优化的磁化规则。这被称为永磁体假设。最后，结果表明，该技术的适用性不仅限于圆形或椭圆形系统，而且可以应用于任何任意形状的横截面。
