Forces on Moving Magnets due to Eddy Currents
- 1 April 1970
- journal article
- research article
- Published by AIP Publishing in Journal of Applied Physics
- Vol. 41 (5), 2067-2071
- https://doi.org/10.1063/1.1659166
Abstract
A magnet or a current‐carrying coil, moving with constant velocity above a conducting plate, will experience magnetic lift and drag forces from the eddy currents induced in the plate. The lift and drag forces are calculated for various coil geometries on the assumption that the conducting plate is thin. For this model, the lift at high speeds approaches the force between the coil and its ``image'' located directly below it, and the drag force falls off as (velocity)−1. The ratio of lift to drag is found to be independent of coil geometry, but the velocity dependence of the lift is greatly affected by the geometry. The ratio of lift to coil weight can be as high as 2000 for a superconducting coil moving at 300 mph at 0.1 m above a conducting plate. The relevance of the calculation to magnetically supported high‐speed vehicles is discussed.Keywords
This publication has 3 references indexed in Scilit:
- Suspension and Guidance of Vehicles by Superconducting MagnetsJournal of Applied Physics, 1969
- Magnetic Suspension and Guidance for High Speed Rockets by Superconducting MagnetsJournal of Applied Physics, 1969
- A Magnetic Field Diffusion ProblemAmerican Journal of Physics, 1969