Abstract: A magnetic refrigeration apparatus includes beds of magnetocaloric material with a hot side and a cold side. The apparatus also includes a magnet to apply a magnetic field to the beds, a heat transfer fluid, a pump to circulate the heat transfer fluid, a hot side heat exchanger, a cold side heat exchanger, and a controller to control the flow of heat transfer fluid from the cold side to the hot side of the beds when the magnetic field on the beds is high at an average flow rate of ?H for a duration ?tH. The controller also controls the flow of heat transfer fluid from the hot side of the beds to the cold side of the beds when the magnetic field on the beds is low at an average flow rate of ?C for a duration ?tC, where ?tC>?tH and ?C<?H.

Abstract: A magnetic refrigeration apparatus includes one or more beds of magnetocaloric material, each having a hot side and a cold side. The apparatus also includes a magnet to apply a time-varying magnetic field to the one or more beds of magnetocaloric material, a heat transfer fluid, a means to circulate the heat transfer fluid, a hot side heat exchanger (HHEX), a cold side heat exchanger (CHEX), and a controller to control the flow of heat transfer fluid from the cold side of the one or more beds to the hot side of the one or more beds when the magnetic field on the one or more beds is high at an average flow rate of ?H for a duration ?tH. The controller also controls the flow of heat transfer fluid from the hot side of the one or more beds to the cold side of the one or more beds when the magnetic field on the one or more beds is low at an average flow rate of ?C for a duration ?tC where ?tC>?tH and ?C<?H and ?tH?H=?tC?C.