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Demagnetization Refrigerator Using Oscillating Rotors

Please click this link for a description of this subject Fixed Rotor Collisions. Here the rotors are bound to a crystal sites and so they have no translational energy. The rotors have a rototional restoring force that is proportional to magnetic field. The rotors oscillatory kinetic energies are variable because the torque constant due to the magnetic field is increased at a larger magnetic field. When the field is increased the rotor gives up kinetic energy by colliding with the discs and this causes what appears as a temperature increase. This temperature increase is reversed when the magnetic field is reduced. The rate of change of the magnetic field has to be slow in order to make the total energy and kinetic energy repeat cycle after cycle. In this simulation of a magnetic solid, the rotors simulate fixed magnetic dipoles and the discs simulate phonons which need to be mobile to carry the heat to the surface of the solid. To act as a refrigerator, when the total kinetic energy is high due to a high magnetic field, the solid is cooled by a gas flowing over its surface. When the magnetic field is withdrawn, the kinetic energy is reduced and the surface of the solid is placed in contact with the object that is to be cooled.