Magnetic device for magneto caloric heat pump regenerator
A magnetic device is provided for a magneto caloric heat pump regenerator. Magnets are arranged within two magnetic flux circuits in a manner than that provides at least four fields of increased magnetic flux density. The regenerator can be used to move working units of magneto caloric material through the fields of increase magnetic flux to provide for heating and cooling as part of heat pump cycle. The orientation of the magnets provides concentrated fields of magnetic flux to induce the magneto caloric effect while optimizing the size of the magnets required to create the fields.
1. A magnetic device for a magnetocaloric heat pump, comprising:
an outer magnetic flux circuit, comprising
a first plurality of magnets arranged in pairs along a circumferential direction of the device with magnet polarity of the pairs alternating between north poles facing inward and north poles facing outward from pair to pair along the circumferential direction;
an inner magnetic flux circuit located radially inward from the outer magnetic flux circuit and comprising
a second plurality of magnets arranged along the circumferential direction and spaced apart from each other; and
wherein the outer magnetic circuit and the inner magnetic circuit create at least four fields of increased magnetic flux density between the outer magnetic circuit and the inner magnetic circuit.
2. The magnetic device for a magnetocaloric heat pump as in claim 1 , wherein the outer magnetic flux circuit further comprises:
a first plurality of flux transmitting elements positioned in an alternating manner along the circumferential direction with the first plurality of magnets.
3. The magnetic device for a magnetocaloric heat pump as in claim 2 , wherein the inner magnetic flux circuit further comprises:
a second plurality of flux transmitting elements positioned in an alternating manner along the circumferential direction with the second plurality of magnets.
4. The magnetic device for a magnetocaloric heat pump as in claim 3 , wherein the first and second plurality of flux transmitting elements comprise iron.
5. The magnetic device for a magnetocaloric heat pump as in claim 4 , wherein the first plurality of magnets and the first plurality of flux transmitting elements are positioned adjacent to, and in contact with, each other along the circumferential direction.
6. The magnetic device for a magnetocaloric heat pump as in claim 5 , wherein the second plurality of magnets and the second plurality of flux transmitting elements are positioned adjacent to, and in contact with, each other along the circumferential direction.
7. The magnetic device for a magnetocaloric heat pump as in claim 1 , wherein the outer magnetic circuit and the inner magnetic circuit are separated by an annulus extending about the circumferential direction.
8. The magnetic device for a magnetocaloric heat pump as in claim 1 , wherein the magnets of each pair of the first plurality of magnets form an angle in the range of 15 degrees to 45 degrees from each other.
9. The magnetic device for a magnetocaloric heat pump as in claim 1 , wherein the magnets of each pair of the first plurality of magnets form an angle of about 30 degrees from each other.
10. The magnetic device for a magnetocaloric heat pump as in claim 1 , wherein the magnets of the second plurality of magnets are arranged in pairs of alternating polarity from pair to pair along the circumferential direction.
11. The magnetic device for a magnetocaloric heat pump as in claim 1 , wherein the magnetic device defines a radial direction, and wherein the magnets of the second plurality of magnets each have a longitudinal axis that is positioned parallel with the radial direction.
12. The magnetic device for a magnetocaloric heat pump as in claim 1 , wherein the magnetic device defines a radial direction, and further comprising a shaft extending along a central axis of the magnetic device, wherein the second plurality of magnets each have a longitudinal axis extending along the radial direction from the shaft.
13. A regenerator for a magnetocaloric heat pump, comprising:
an outer magnetic flux circuit, comprising
a first plurality of magnets arranged in pairs along a circumferential direction of the heat pump with magnet polarity of the pairs alternating between north poles oriented inward and north poles oriented outward from pair to pair along the circumferential direction;
an inner magnetic flux circuit located radially inward from the outer magnetic flux circuit and comprising
a second plurality of magnets arranged along the circumferential direction and spaced apart from each other;
wherein the outer magnetic circuit and the inner magnetic circuit create at least four fields of increased magnetic flux density along an annulus positioned between the outer magnetic circuit and the inner magnetic circuit; and
a plurality of working units arranged adjacent to each along the circumferential direction and extending between a first end of the regenerator and a second end of the regenerator, each working unit comprising magneto caloric material, wherein the working units are rotatable relative to the outer and inner magnetic flux circuits.
14. The regenerator for a magnetocaloric heat pump as in claim 13 , further comprising a housing defining a plurality of chambers positioned adjacent to each other along the circumferential direction, each chamber including at least one of the plurality of working units.
15. The regenerator for a magnetocaloric heat pump as in claim 13 , wherein the outer magnetic flux circuit further comprises:
a first plurality of flux transmitting elements positioned in an alternating manner along the circumferential direction with the first plurality of magnets.
16. The regenerator for a magnetocaloric heat pump as in claim 15 , wherein the inner magnetic flux circuit further comprises:
a second plurality of flux transmitting elements positioned in an alternating manner along the circumferential direction with the second plurality of magnets.
17. The regenerator for a magnetocaloric heat pump as in claim 16 , wherein the first and second plurality of flux transmitting elements comprise iron.
18. The regenerator for a magnetocaloric heat pump as in claim 13 , wherein the outer magnetic circuit and the inner magnetic circuit are separated by an annulus extending about the circumferential direction.