In this study, magnetic damping (also known as an eddy current damping) which is generated by the eddy current induced in a conductive material subjected to a time-varying magnetic field (created by several rare earth permanent magnets) is explored. Two configurations of eddy current dampers (ECDs) are investigated in this paper. The first configuration is made up of a stack of eight Neodymium NdFeB (N42) permanent magnets separated by seven pole pieces made of nearly pure iron, assembled on a shaft moving back and forth in the confines of an aluminum tube. The second configuration of the eddy current damper contains a conductive copper plate and five NdFeB (N50) magnet plates placed on two iron plates that move in parallel and close vicinity of the copper plates. In both damping schemes, the interaction between the magnetic field of the permanent magnet assembly and the magnetic field of the electromagnet created by the eddy current within the conductor results in energy dissipation. The two configurations of eddy current damper are modeled numerically and verified experimentally. The motivation for conducting this study is to explore the use of eddy current damping as an alternative to liquid-based viscous and solid-based viscoelastic damping mechanisms.

This content is only available via PDF.
You do not currently have access to this content.