A magnetic damper for low temperature

Abstract

A new magnetic damper is developed for the suspension and vibration isolation of precise instruments working in low-temperature and vacuum environments. The damper comprises permanent magnets, a non-magnetic conductor tube, and a spring, and a room-temperature prototype is designed in COMSOL Multiphysics and verified by experiments. A tubular eddy current damper is chosen because it has less leakage flux than the flat type and better usage of magnetic flux, which leads to higher eddy currents. The adjacent magnets arranged in the reverse direction of magnetization can contribute to obtaining a compact damper. COMSOL Multiphysics is proven to be effective software to predict the performance of an eddy current damper compared with the existing experimental and theoretical results. To apply the damper to low-temperature conditions, the selections of non-magnetic tubes and the permanent magnet are thoroughly analyzed. This study offers the applicability of the magnetic damper in the suspension and vibration isolation of precise instruments and provides suggestions for the design of low-temperature and vacuum magnetic dampers.