Trapped magnetic field distribution above a superconducting linear Halbach array
View / Open Files
Authors
Houbart, M
Fagnard, J-F
Dular, J
Dennis, AR
Namburi, DK
Durrell, JH
Geuzaine, C
Vanderheyden, B
Vanderbemden, P
Publication Date
2022Journal Title
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
ISSN
0953-2048
Publisher
IOP Publishing
Type
Article
This Version
AM
Metadata
Show full item recordCitation
Houbart, M., Fagnard, J., Dular, J., Dennis, A., Namburi, D., Durrell, J., Geuzaine, C., et al. (2022). Trapped magnetic field distribution above a superconducting linear Halbach array. SUPERCONDUCTOR SCIENCE & TECHNOLOGY https://doi.org/10.1088/1361-6668/ac68a7
Abstract
In applications requiring a large magnetic force, permanent magnets with non-parallel magnetization directions can be assembled in a Halbach array to generate a large gradient of magnetic flux density. The saturation magnetization of permanent magnets, however, brings a fundamental limit on the performance of this configuration. In the present work, we investigate experimentally the assembly of cuboid bulk, large grain melt-textured YBa2Cu3O7−x superconductors (∼14×14×14 mm3) with orthogonal c-axes so as to form a basic unit of Halbach array. The experiments are carried out at 77 K.
The experimental distribution of the magnetic flux density above the array of trapped-field superconductors is compared to a similar array made of permanent magnets. A simple analytical model is developed and is shown to accurately reproduce the main experimental observations. The results suggest that a redistribution occurs in the current flowing in the central sample when the distance between the superconductors is reduced, whereas the neighbouring superconductors are unaffected. It is shown that this current redistribution yields a reduced contribution of the central sample to the magnetic flux density above the centre of the array and a new negative contribution associated with stray fields to the magnetic flux density at this location. This interpretation is confirmed by modelling of the distribution of transport currents in the superconductor using a 3D finite element model.
Sponsorship
Belgian FNRS under grant CDR n° J.0218.20 (35325237). Michel Houbart is recipient of a FRS- FNRS Research Fellow grant.
Embargo Lift Date
2023-06-01
Identifiers
External DOI: https://doi.org/10.1088/1361-6668/ac68a7
This record's URL: https://www.repository.cam.ac.uk/handle/1810/336231
Statistics
Total file downloads (since January 2020). For more information on metrics see the
IRUS guide.