Presentation Information
[WBP2-06]Numerical Investigation and Mitigation Strategies for Flux Jumps Prevention in MgB2 Bulks
*Michela Fracasso1,2, Roberto Gerbaldo1,2, Gianluca Ghigo1,2, Yiteng Xing3, Pierre Bernstein3, Jacques Noudem3, Laura Gozzelino1,2 (1. Department of Applied Science and Technology, Politecnico di Torino, Torino (Italy), 2. Istituto Nazionale di Fisica Nucleare, Sezione di Torino, Torino (Italy), 3. CRISMAT, UMR 6508 CNRS ENSICAEN-UNICAEN, Caen (France))
Keywords:
MgB2,cryomagnet,flux-jump,magnetic shielding,trapped field
The suitable current-carrying properties of MgB2 across high-angle grain boundaries have enabled the fabrication of bulk components with tailored geometries for applications such as magnetic shielding and trapped-field magnets [1,2]. Nevertheless, their performances at low temperatures can be limited severely by thermomagnetic instabilities, such as flux jumps [3,4]. Understanding, predicting and mitigating such events is essential for reliable device operation.In this work, we numerically investigated the flux-jump phenomenon by coupling the heat diffusion equation with electromagnetic equations expressed in terms of the magnetic vector potential (A) [4,5], extending earlier experimental studies on flux jumps in half-closed cylindrical MgB2 shields [4] and in disk-shaped trapped-field magnets [6]. The model, implemented in COMSOL Multiphysics® using the finite element method [7] and validated through direct comparison with experimental data [4], enables a detailed analysis of local magnetic field, temperature, and current density evolution during flux-jump events. Once validated, the model was employed to assess strategies aimed at mitigating flux-jump occurrence. Simulations assessed the effectiveness of increasing the intrinsic thermal conductivity of MgB2 bulks, improving thermal exchange with the cryogenic stage, and incorporating ferromagnetic elements. The latter proved beneficial both for thermal stabilisation and for reinforcing magnetic performances [7,8].
References
1) Z. Zhang et al., Superconductivity 3 (2022) 100015
2) T. Prikhna et al., Materials 17 (2024) 2787
3) D.A. Moseley et al., Supercond. Sci. Technol. 35 (2022) 085003
4) M. Fracasso et al., Supercond. Sci. Technol. 36 (2023) 044001
5) M. Solovyov et al., Supercond. Sci. Technol., 32 (2019) 115001
6) K. Berger et al., IEEE Trans. Appl. Supercond. 26 (2016) 6801005
7) N. Rotheudt, M. Fracasso et al., Supercond. Sci. Technol., 38 (2025) 043002
8) M. Fracasso et al., Materials, 17 (2024) 1201
Acknowledgements
This study was partially carried out within the Space It Up project funded by the Italian Space Agency, ASI, and the Ministry of University and Research, MUR, under contract n. 2024-5-E.0 - CUP n. I53D24000060005. We acknowledge Petre Badica, Mihai Alexandru Grigoroscuta, MihailBurdusel and Gheorghe Virgil Aldica for providing us the MgB2 shields. We acknowledge Fedor Gömöry and Mykola Solovyov for their contribution with the numerical approach.
References
1) Z. Zhang et al., Superconductivity 3 (2022) 100015
2) T. Prikhna et al., Materials 17 (2024) 2787
3) D.A. Moseley et al., Supercond. Sci. Technol. 35 (2022) 085003
4) M. Fracasso et al., Supercond. Sci. Technol. 36 (2023) 044001
5) M. Solovyov et al., Supercond. Sci. Technol., 32 (2019) 115001
6) K. Berger et al., IEEE Trans. Appl. Supercond. 26 (2016) 6801005
7) N. Rotheudt, M. Fracasso et al., Supercond. Sci. Technol., 38 (2025) 043002
8) M. Fracasso et al., Materials, 17 (2024) 1201
Acknowledgements
This study was partially carried out within the Space It Up project funded by the Italian Space Agency, ASI, and the Ministry of University and Research, MUR, under contract n. 2024-5-E.0 - CUP n. I53D24000060005. We acknowledge Petre Badica, Mihai Alexandru Grigoroscuta, MihailBurdusel and Gheorghe Virgil Aldica for providing us the MgB2 shields. We acknowledge Fedor Gömöry and Mykola Solovyov for their contribution with the numerical approach.