Correlation of experimental data and three-dimensional finite element modeling of a spinning magnet array

Journal Article · Thu Sep 01 04:00:00 EDT 1994 · IEEE Transactions on Magnetics

DOI:https://doi.org/10.1109/20.312569· OSTI ID:37161

Lorimer, W L; Lieu, D K ^[1]; Hull, J R; Mulcahy, T M; Rossing, T D ^[2]

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1. Univ. of California, Berkeley, CA (United States). Dept. of Mechanical Engineering
2. Argonne National Lab., IL (United States)

Drag forces due to eddy currents induced by the relative motion of a conductor and a magnetic field occur in many practical devices: motors, brakes, magnetic bearings, and magnetically levitated vehicles. Here, a magnet array was spun above an aluminum disk, and the drag torque was measured for various speeds and gap sizes. Drag torques calculated using a three-dimensional finite element program were consistent with measured values. The finite element model was also used to determine the effects of the polarity and position of magnets in the source array. The peak torque was shown to occur when magnets are located at a radius equal to 70% of the disk radius. A magnet array with alternate magnets reversed was shown to produce more than twice the drag of an array comprised of parallel magnets. An approximation for fields under the magnet centers was obtained using a two-dimensional analytical solution.

• OSTI ID: 37161
• Report Number(s): CONF-931013--
• Journal Information: IEEE Transactions on Magnetics, Journal Name: IEEE Transactions on Magnetics Journal Issue: 5Pt2 Vol. 30; ISSN IEMGAQ; ISSN 0018-9464
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
COMPARATIVE EVALUATIONS
DESIGN
DRAG
ELECTRIC CONDUCTORS
EXPERIMENTAL DATA
PERMANENT MAGNETS
ROTATION
THEORETICAL DATA
TORQUE