Rotating bed magnetic refrigeration apparatus

Abstract

A rotating magnetic refrigeration apparatus has magnetic regenerator beds arranged in a ring that is mounted for rotation about a central axis, such that each bed moves into and out of a magnetic field provided by a magnet as the ring rotates. Heat transfer fluid is directed to and from the regenerator beds by a distribution valve which is connected by conduits to the hot and cold ends of the beds and which rotates with the ring of beds. The distribution valve has a stationary valve member which is connected by conduits to a hot heat exchanger and to a cold heat exchanger. The beds include magnetocaloric material that is porous and that allows heat transfer fluid to flow therethrough. The distribution valve directs heat transfer fluid to the hot end of a bed that is outside of the magnetic field which flows therethrough to the cold end where it is directed back to the distribution valve and, when a bed is in the magnetic field, the distribution valve directs fluid to the cold end of the bed for flow therethrough to the hot end, where the fluid is directed back to the distribution valve, completing an active magnetic regenerator cycle. The fluid flowing through each conduit flows only in a single direction or remains stationary, minimizing dead volume in the conduits.