Magnetocaloric device

Abstract

A magneto-caloric (MC) device is disclosed. The MC device comprise a rotor, a housing disposed about and concentric with the rotor and mechanically coupled to the rotor, wherein the housing comprises at least one axial slot, at least one set of MC elements, wherein each set of MC elements comprises at least one MC element, and at least one MC element of each set of MC elements is disposed within each of the at least one axial slots, and at least one working-segment corresponding to each set of MC elements, wherein each working-segment is disposed axially around the rotor and external to the housing, and wherein each working-segment comprises, a yoke substantially defining an inner volume comprising a first inner volume and a second inner volume, and a magnetic field production (MFP) unit magnetically coupled to the yoke and configured to provide a magnetic field within the first inner volume.

1 . A magneto-caloric (MC) device, comprising:
 a rotor;   a housing disposed about and concentric with the rotor and mechanically coupled to the rotor, wherein the housing comprises at least one axial slot;   at least one set of MC elements, wherein each set of MC elements comprises at least one MC element, and at least one MC element of each set of MC elements is disposed within each of the at least one axial slots; and   at least one working-segment corresponding to each set of MC elements, wherein each working-segment is disposed axially around the rotor and external to the housing, and wherein each working-segment comprises:
 a yoke substantially defining an inner volume comprising a first inner volume and a second inner volume; and 
 a magnetic field production (MFP) unit magnetically coupled to the yoke and configured to provide a magnetic field within the first inner volume; 
   wherein the rotor is configured to oscillate the at least one axial slot so that the MC elements disposed therein are oscillated between their respective first and second inner volumes, which MC elements are thereby subjected to magnetization-demagnetization cycling.   
     
     
         2 . The MC device of  claim 1 , wherein the rotor is configured for semi-rotatory motion. 
     
     
         3 . The MC device of  claim 1 , wherein the housing comprises, a hermetic housing, or a semi-hermetic housing. 
     
     
         4 . The MC device of  claim 1 , further comprising an air-gap mediate the MFP unit and the housing. 
     
     
         5 . The MC device of  claim 1 , wherein the MFP unit comprises at least one of an electromagnet, a permanent magnet, a superconducting magnet, or a group of permanent magnets in a Hallbach arrangement. 
     
     
         6 . The MC device of  claim 1 , wherein the MFP unit can produce a magnetic field of up to about 10 Tesla. 
     
     
         7 . The MC device of  claim 1 , further comprising a magnetic field concentrator (MFC) unit configured to concentrate the magnetic field produced by the MFP unit. 
     
     
         8 . The MC device of  claim 1 , wherein each of the at least one set of MC elements comprises alloys including gadolinium (Gd), alloys including manganese and iron, alloys including lanthanum and silicon, alloys of manganese and tin, alloys including nickel, manganese and gadolinium, alloys including lanthanum and manganese and oxygen, and combinations thereof. 
     
     
         9 . The MC device of  claim 1 , wherein the at least one set of MC elements comprises a plurality of sets of MC elements, wherein each set of the plurality of sets of MC elements comprises the same number of MC elements. 
     
     
         10 . The MC device of  claim 1 , wherein the housing comprises a non-magnetic material. 
     
     
         11 . The MC device of  claim 1 , wherein the rotor comprises a magnetically permeable material. 
     
     
         12 . The MC device of  claim 1 , comprising a plurality of sets of MC elements and a plurality of working-segments. 
     
     
         13 . The MC device of  claim 12 , wherein the sets of MC elements comprise MC materials comprising more than one composition. 
     
     
         14 . A refrigeration system, comprising:
 a first heat exchanger;   a second heat exchanger;   a MC device, comprising:   a rotor,   a housing disposed about and concentric with the rotor and mechanically coupled to the rotor, wherein the housing comprises at least one axial slot;   at least one set of MC elements, wherein each set of MC elements comprises at least one MC element, and at least one MC element of each set of MC elements is disposed within each of the at least one axial slots;   and at least one working-segment corresponding to each set of MC elements wherein each working-segment is disposed axially around the rotor and external to the housing, and wherein each working-segment comprises:
 a yoke substantially defining an inner volume comprising a first inner volume and a second inner volume; and 
 a magnetic field production (MFP) unit magnetically coupled to the yoke and configured to provide a magnetic field within a first portion of the inner volume; 
   wherein the rotor is configured to oscillate the at least one axial slot so that the MC elements disposed therein are oscillated between their respective first and second inner volumes, which MC elements are thereby subjected to heating-cooling cycling; and   a fluid-circuit mechanically coupled to the housing and configured to selectively thermally couple the at least two axial slots to the first heat exchanger or to the second heat exchanger, or to the first heat exchanger and to the second heat exchanger.   
     
     
         15 . The refrigeration system of  claim 14 , wherein the housing comprises a hermetic housing, or a semi-hermetic housing. 
     
     
         16 . The refrigeration system of  claim 14 , wherein the fluid-circuit comprises at least one solenoid valve. 
     
     
         17 . The refrigeration system of  claim 16 , wherein a mode of operation of the solenoid valve comprises a latching mechanism. 
     
     
         18 . The refrigeration system of  claim 17 , wherein the latching mechanism comprises magnetic latching, mechanical latching, hydraulic latching, pneumatic latching, or combinations thereof. 
     
     
         19 . The refrigeration system of  claim 13 , further comprising a thermal fluid wherein the thermal fluid comprises at least one liquid, or at least one gas, or combinations thereof. 
     
     
         20 . The refrigeration system of  claim 19 , configured to enable the first heat exchanger to extract heat from the thermal fluid. 
     
     
         21 . The refrigeration system of  claim 19 , configured to enable the second heat exchanger to inject heat to the thermal fluid. 
     
     
         22 . A magnetocaloric (MC) device comprising:
 a rotor comprising a magnetically permeable material;   a hermetic housing disposed about and concentric with the rotor and mechanically coupled to the rotor, wherein the hermetic housing comprises at least one axial slots;   at least one set of MC elements, wherein each set of MC elements comprises at least one MC element comprising a finned structure, and at least one MC element of each set of MC elements is disposed within each of the at least one axial slot; and   at least one working-segment corresponding to each set of MC elements, wherein each working-segment is disposed axially around the rotor and external to the hermetic housing, and wherein each working-segment comprises:
 a yoke formed as a mechanically closed loop defining an inner volume comprising a first inner volume and a second inner volume, wherein the yoke comprises a magnetically permeable material; and 
 a magnetic field generation and concentration (MFGC) unit magnetically coupled to the yoke and configured to provide a magnetic field within the first inner volume; 
   wherein the rotor is configured to oscillate the at least one axial slot so that the MC elements disposed therein are oscillated between their respective first and second inner volumes, which MC elements are thereby subjected to magnetization-demagnetization cycling.   
     
     
         23 . The MC device of  claim 22 , wherein the MC elements comprise a protective coating. 
     
     
         24 . The MC device of  claim 23 , wherein the coating comprises a nitride compound, nickel, aluminum, copper, carbon, silver, gold, or combinations thereof. 
     
     
         25 . The MC device of  claim 22 , wherein at least one MC element comprises a double finned structure.