원문정보
초록
영어
This study explores the enhancement of magnetic field homogeneity in Nuclear Magnetic Resonance (NMR) magnets through optimized ferromagnetic shimming design. Traditional shimming techniques, which involve attaching ferromagnetic materials to the magnet bore, often lack manufacturability considerations, limiting their effectiveness in real-world applications. To address this, we employ a topology optimization (TO) approach using the Solid Isotropic Material with Penalization (SIMP) scheme for design parametrization. The proposed optimization framework includes volume and perimeter constraints to improve the practical manufacturability of the shim. Numerical analysis demonstrates that the TO-based design method achieves superior magnetic field homogeneity, achieving 0.45 ppm with integer thickness shims, compared to conventional designs. This approach also effectively reduces manufacturing complexity by minimizing design sensitivity to the thickness and placement of individual shimming elements. The proposed design framework is broadly applicable to superconducting magnets in NMR and MRI systems, where high magnetic field homogeneity is essential. This study presents a significant advancement in ferromagnetic shimming technology, offering a viable solution for enhancing the performance and manufacturability of high-precision magnetic field devices.
목차
1. 서론
2. 자기장 보정 이론
2.1. 자장 경사도를 이용한 자기장 분포
2.2. 수동보정법 이론
2.3. 수동보정장치 설계
3. 자장 균일도를 위한 위상 최적설계
3.1. 위상최적설계 문제 구성
3.2. 제작성 확보를 위한 둘레 길이 제약 조건
4. 결론
ACKNOWLEDGMENT
REFERENCES
