Application of Lenz's Law to Magnetic Levitation

ORAL

Abstract

Lenz’s law can be used to achieve magnetic levitation through induced currents. The law states that changing magnetic fields will induce an electric current, or eddy current, in a conductor surface such that it produces an opposing magnetic field.We will explore the constraints for magnetic levitation through the use of eddy currents, induced by a rotating disk of a permanent-magnet assembly. There are no eddy currents when the disk is stationary, but a rotating disk yields formation of two opposing eddy currents over the dimensions of the individual permanent magnets in the assembly. One of the eddy current repels the magnetic field that created it, while the other eddy current generates an opposite magnetic field resisting a change in the magnetic flux. If the rotation frequency of the magnet assembly is comparable to the typical lifetime of the eddy currents, magnetic levitation may be achieved. We will discuss the parameters that need to be considered for use in an actual device.

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Authors

  • Juan Treto

    New Mexico State University

  • Colin Roberts

    High Precision Devices, Boulder, CO, Raytheon, Tucson, AZ, Seagate Technology, Minneapolis, MN, Ball Aerospace (retired), Bloomfield, CO, New Mexico State University, Brigham Young University, Colorado State University, Heinrich-Heine-Universitat Dusseldorf, National Security Technologies, Universidad de Buenos Aires, Colorado State Univ, Colorado College, Utah State University, Advisor, Material Physics Group, Utah State University, Box Elder Innovations, LLC, JILA and Department of Physics, CU Boulder, JILA and Department of Mathematics, CU Boulder, Colorado State University, Fort Collins, Colorado 80523, USA, JILA, NIST and the University of Colorado, Boulder, NIST, University of Colorado / NIST, University of Colorado/JILA, Colorado Sch of Mines, Colorado School of Mines, Southwestern Indian Polytechnic Institute, UC-Berkeley, Colorado State University, Fort Collins, CO, Wroclaw University of Science and Technology, Wroclaw, Poland, JILA, University of Colorado and NIST, Harvard University and Harvard-MIT Center for Ultracold Atoms, Univ of Colorado - Boulder, USAFA, Univ of Denver, Boyce Research Initiatives and Educational Foundation, Brilliant Sky Observatory, San Diego Mesa College, Utah Valley University, University of Colorado Boulder, Brigham Young Univ - Provo, Oak Ridge National Laboratory, University of Sherbrooke, NIST Boulder, Universidad Complutense de Madrid, Electrical and Computer Engineering Department, Colorado State University, Fort Collins, Co 80525, Lawrence Livermore National Lab. (United States), Physics Department, Colorado State University, Fort Collins, Co 80525, JILA, Department of Physics, University of Colorado Boulder, Los Alamos National Laboratory, University of Alabama, University of Wyoming, University of Guelph, University of Guelph, Canadian Light source