In this paper, we propose a new concept of “multi-bore” NMR (nuclear magnetic resonance) magnet, where multiple high temperature superconductor (HTS) NNR magnets are closely positioned to form a magnet array. A key benefit of the multi-bore NMR system over its single-bore counterpart may be that it shares some common parts, especially cryogenic system and current lead, thus the overall multi-bore NMR system could be substantially more compact than the same number of single-bore NMR systems. However, due to the close positioning of multiple HTS NMR magnets, the electromagnetic interference among neighbor magnets may be significant, which leads to challenges in: (1) obtaining NMR quality field uniformity; (2) keeping sustainable electromagnetic force and stress; and (3) safe quench protection. This paper presents our initial design of a 4-by-4 multi-bore NMR magnet array. Then, a set of ferro-shims is designed to obtain a target field uniformity for all magnet components. The unbalanced Lorentz force on each magnet is also calculated with a first-cut design of the support structure. Finally, a post-quench analysis is performed with mutual inductances among magnets taken into consideration.
Keywords: Array of magnets, field uniformity, HTS magnet, multi-bore NMR
Category: D01 - Magnets for NMR
This work was supported by the Korea Basic Science Institute (KBSI) grant D39611. It was also partly supported by the National Research Foundation of Korea as a part of Mid-Career Research Program (No. 2018R1A2B3009249).