Abstract: A magnetic refrigeration apparatus according to the present disclosure includes a magnetic-field source and two or more bed rings. The bed rings can be arranged in pairs with shared cold and hot fluid plenums. A flow of heat transfer fluid may pass at least partially radially through the shared fluid plenum or through a connection between the fluid plenum and one or more flow tubes. The MR apparatus and systems of the present disclosure may further include one or more circumferential flux returns with radial through-hole passageways to accommodate flow tubing. For apparatus configurations with an even number of bed rings, the axial dimension of the passageways may be smaller than the circumferential dimension of the passageways.

Abstract: A magnetic refrigeration apparatus includes one or more beds of magnetocaloric material arranged along a circumferential direction. The apparatus also includes a heat transfer fluid, one or more hot side heat exchangers (HHEX), one or more pumps or fluid displacement devices configured to move the heat transfer fluid, and a magnetic-field source. The magnetic-field source generates magnetic flux oriented substantially in a radial direction through the beds. The field source advantageously includes one or more pole pieces, one or more axial-end magnets, and one or more axial-end flux return pieces. Additionally, one or more circumferential flux returns, one or more gap flux return pieces, one or more side magnets, and one or more side flux return pieces can be added to increase system performance and reduce cost.

Abstract: A magnetic refrigeration apparatus according to the present disclosure includes a magnetic-field source and two or more bed rings. The bed rings can be arranged in pairs with shared cold and hot fluid plenums. A flow of heat transfer fluid may pass at least partially radially through the shared fluid plenum or through a connection between the fluid plenum and one or more flow tubes. The MR apparatus and systems of the present disclosure may further include one or more circumferential flux returns with radial through-hole passageways to accommodate flow tubing. For apparatus configurations with an even number of bed rings, the axial dimension of the passageways may be smaller than the circumferential dimension of the passageways.

Abstract: A magnetic refrigeration apparatus includes one or more beds of magnetocaloric material arranged along a circumferential direction. The apparatus also includes a heat transfer fluid, one or more hot side heat exchangers (HHEX), one or more pumps or fluid displacement devices configured to move the heat transfer fluid, and a magnetic-field source. The magnetic-field source generates magnetic flux oriented substantially in a radial direction through the beds. The field source advantageously includes one or more pole pieces, one or more axial-end magnets, and one or more axial-end flux return pieces. Additionally, one or more circumferential flux returns, one or more gap flux return pieces, one or more side magnets, and one or more side flux return pieces can be added to increase system performance and reduce cost.

Abstract: A magnetic refrigeration system provides flow-balanced channels between fluid control valves and the magnetocaloric beds to eliminate inefficiencies caused by unequal utilization of the magnetic beds from flow variations.

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: An active magnetic regenerative (AMR) refrigerator apparatus can include at least one AMR bed with a first end and a second end and a first heat exchanger (HEX) with a first end and a second end. The AMR refrigerator can also include a first pipe that fluidly connects the first end of the first HEX to the first end of the AMR bed and a second pipe that fluidly connects the second end of the first HEX to the first end of the AMR bed. The first pipe can divide into two or more sub-passages at the AMR bed. The second pipe can divide into two or more sub-passages at the AMR bed. The sub-passages of the first pipe and the second pipe can interleave at the AMR bed.

Abstract: The present invention provides a porous thermal regenerator apparatus and method of making a porous thermal regenerator comprised of metallic or intermetallic particles that are held together in a porous three dimensional network by a binding agent (such as epoxy). One aspect of the apparatus is that the porosity of the porous thermal regenerator is greater than the tapped porosity of the particles comprising the porous thermal regenerator; moreover, the high-porosity apparatus is durable, that is, it remains intact when exposed to strong time-varying magnetic forces while immersed in aqueous fluid. This high porosity, when combined with high strength and aqueous heat transfer fluid stability, leads to improved porous thermal regenerators and concomitantly to magnetic refrigerators with improved performance.

Abstract: A magnetic refrigeration system provides a rotary valve design that balances the forces needed to seal valve surfaces, reduces influence of wear on leakage, makes assembly and adjustment of the valve easier, reduces potential for bypass flows, reduces stress on and corrosion of the drive shaft, and provides a more compact system.

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.

Abstract: An active magnetic regenerative (AMR) refrigerator apparatus can include at least one AMR bed with a first end and a second end and a first heat exchanger (HEX) with a first end and a second end. The AMR refrigerator can also include a first pipe that fluidly connects the first end of the first HEX to the first end of the AMR bed and a second pipe that fluidly connects the second end of the first HEX to the first end of the AMR bed. The first pipe can divide into two or more sub-passages at the AMR bed. The second pipe can divide into two or more sub-passages at the AMR bed. The sub-passages of the first pipe and the second pipe can interleave at the AMR bed.

Abstract: A magnetic refrigeration system provides flow-balanced channels between fluid control valves and the magnetocaloric beds to eliminate inefficiencies caused by unequal utilization of the magnetic beds from flow variations.

Abstract: The present invention provides a porous thermal regenerator apparatus and method of making a porous thermal regenerator comprised of metallic or intermetallic particles that are held together in a porous three dimensional network by a binding agent (such as epoxy). One aspect of the apparatus is that the porosity of the porous thermal regenerator is greater than the tapped porosity of the particles comprising the porous thermal regenerator; moreover, the high-porosity apparatus is durable, that is, it remains intact when exposed to strong time-varying magnetic forces while immersed in aqueous fluid. This high porosity, when combined with high strength and aqueous heat transfer fluid stability, leads to improved porous thermal regenerators and concomitantly to magnetic refrigerators with improved performance.