Rotating bed magnetic refrigeration apparatus

• US 6,526,759 B2
• Filed: 08/08/2001
• Issued: 03/04/2003
• Est. Priority Date: 08/09/2000
• Status: Expired due to Term

• Current Assignee: Astronautics Corporation of America
• Original Assignee: Astronautics Corporation of America
• Inventors: Jastrab, Alexander G., Sternberg, Alexander, Chell, Jeremy Jonathan, Boeder, Andre M., Lawton, Lewis M., Zimm, Carl B.
• Primary Examiner(s): CAPOSSELA, RONALD C
• Application Number:
  US09/925,032
• Publication Number:
  US 20020053209A1
• Time in Patent Office: 573 Days
• Field of Search: 62/31, 62/6
• US Class Current: 62/3.1
• CPC Class Codes: F25B 21/00 Machines, plants or systems, using electric or magnetic effects
• CPC Class Codes: F25B 2321/0021 with a static fixed magnet
• CPC Class Codes: Y02B 30/00 Energy efficient heating, ventilation or air conditioning [HVAC]

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.

Claims

1. A method of providing regenerative cooling of a heat transfer fluid comprising the steps of:

(a) providing a ring of an even number of magnetic regenerator beds, each bed including material that exhibits the magnetocaloric effect, that is porous and allows the flow of heat transfer fluid through such magnetocaloric material, each bed having a hot end and a cold end, the beds arranged in a circular ring with the cold end of each bed adjacent to the cold end of an adjacent bed and the hot end of each bed adjacent to the hot end of an adjacent bed;

(b) rotating the ring of regenerator beds through a magnetic field to alternately apply a magnetic field to and remove the magnetic field from each of the regenerator beds as the ring of beds rotates;

(c) passing heat transfer fluid through a regenerator bed from the hot end of the bed to the cold end when the bed is not in the magnetic field so that the heat transfer fluid is in circumferential flow with respect to the central axis about which the bed is rotated, and passing heat transfer fluid through the regenerator bed from the cold end to the hot end of the bed in a circumferential flow when the ring of beds is rotated so that the bed is in the magnetic field.

2. The method of claim 1 including drawing heat from heat transfer fluid that has passed through the regenerator bed from the cold end to the hot end of the bed when the bed is in the magnetic field.

3. The method of claim 2 further including the step of transferring heat to heat transfer fluid that is then passed to and through a regenerator bed from the cold end to the hot end of the bed when the bed is in the magnetic field.

4. Rotating magnetic refrigeration-heat pump apparatus comprising:

(a) a ring of magnetic regenerator beds mounted for rotation about a central axis and a drive for driving the ring of magnetic regenerator beds in rotation about the central axis, each bed including material that exhibits the magnetocaloric effect that is porous and allows the flow of heat transfer fluid through such magnetocaloric material in circumferential flow, each bed having a hot end and a cold end;

(b) a magnet providing a magnetic field that passes through at least one but not all of the regenerator beds in the ring so that at least one bed is in the magnetic field and at least one bed is outside of the magnetic field;

(c) a hot heat exchanger;

(d) a cold heat exchanger;

(e) a distribution valve connected by conduits to the hot heat exchanger and to the cold heat exchanger and by conduits to the hot end and cold end of each magnetic regenerator bed, the distribution valve switching as the ring of regenerator beds rotates to direct heat transfer fluid in a circuit from a bed which is outside the magnetic field through the distribution valve to the cold heat exchanger and then back through the distribution valve to the bed that is in the magnetic field and then through the distribution valve to the hot heat exchanger and then back through the distribution valve to a bed that is outside the magnetic field, the distribution valve directing the flow therethrough so that the flow through the conduits is maintained in the same direction and with the direction of flow through each bed when the bed is outside the magnetic field reversed from the direction of flow when the bed is in the magnetic field; and

(f) a pump connected in the conduits to drive heat transfer fluid through the hot and cold heat exchangers, the conduits, and the distribution valve.

5. The refrigerator apparatus of claim 4 wherein corresponding inlet and outlet conduits between the distribution valve and the beds are merged via a Y connector into a single inlet/outlet port at the beds.

6. The refrigeration apparatus of claim 4 wherein there are an even number of magnetic regenerator beds, the beds arranged in the circular ring with the cold end of each bed adjacent to the cold end of an adjacent bed and the hot end of each bed adjacent to the hot end of an adjacent bed, the adjacent cold ends of the beds open to each other for fluid flow and having one common cold end input port and one common cold end output port, the adjacent hot ends of the beds separated by flow proof separators and having an input and an output port for the hot end of each bed.

7. The refrigeration apparatus of claim 4 wherein the distribution valve includes a stationary valve member and a rotating valve member that is mounted to rotate in engagement with the stationary valve member about the central axis, and wherein conduits extend from the rotating valve member to the hot ends and cold ends of each bed to distribute fluid between the distribution valve and the beds, the rotating valve member rotating with the ring of regenerator beds.

8. The refrigeration apparatus of claim 7 wherein the distribution valve comprises an inner stationary valve member and an outer rotating valve member that is mounted to rotate in engagement with the stationary valve member about the central axis, the stationary valve member having two cold fluid chambers and two hot fluid chambers, the rotating valve member having first cold fluid ports therein that as the rotating valve member rotates are successively in communication with the first cold fluid chamber, second cold fluid ports therein that, as the rotating valve member rotates, are successively in communication with the second cold fluid chamber, the rotating valve member further having first hot fluid ports that, as the rotating valve member rotates, are successively in communication with the first hot fluid chamber, and second hot fluid ports that, as the rotating valve member rotates, are successively in communication with the second hot fluid chamber, and channels in the stationary valve member extending from two hot fluid openings to the first and second hot fluid chambers and from two cold fluid openings to the first and second cold fluid chambers, and wherein conduits extend from the cold input ports of the beds to the ports in the rotating valve member that come successively in communication with the first of the cold fluid chambers, conduits extend from the cold output ports of the beds to the ports in the rotating valve member that come successively in communication with the second of the cold fluid chambers, conduits extend from the hot output ports of the beds to the ports in the rotating valve member that come successively in communication with the first of the hot fluid chambers, and conduits extend from the hot input ports of the beds to the ports of the rotating valve member that come successively in communication with the second of the hot fluid chambers and, further, conduits extend from the outlet of the cold heat exchanger to a cold fluid opening of the stationary valve member that is in communication with the first cold fluid chamber, conduits extend from the inlet of the cold heat exchanger to a cold fluid opening of the stationary valve member that is in communication with the second cold fluid chamber, conduits extend from a hot fluid opening of the stationary valve member in communication with the first hot fluid chamber to the inlet of the hot heat exchanger through a pump, and conduits extend from the outlet of the hot heat exchanger to a hot fluid opening in the stationary valve member in communication with the second hot fluid chamber in the stationary valve member.

9. The refrigeration apparatus of claim 8 wherein the stationary valve member has a top end and a bottom end and wherein the cold fluid openings in the stationary valve member face axially at one of the ends and the hot fluid openings in the stationary valve member face axially at the other end.

10. The refrigeration apparatus of claim 7 wherein the magnet comprises a permanent magnet.

11. The refrigeration apparatus of claim of 10 wherein the magnet is C-shaped.

12. The refrigeration apparatus of claim 7 further including a mounting platform mounted for rotation about the central axis, the conduits that extend from the rotating valve member to the beds having sections extending from the mounting platform to the ring of beds, the ring of beds supported by the mounting platform for rotation about the central axis.

13. The refrigeration apparatus of claim 12 wherein the conduit sections extending from the mounting platform to the beds providing physical support for the ring of beds.

14. The refrigeration apparatus of claim 12 wherein the rotating valve member and the mounting platform are connected together to rotate together about the central axis.

15. The refrigeration apparatus of claim 7 wherein the stationary valve member and the rotating valve member are formed as disks with flat faces in engagement with one another, the rotating valve member mounted to rotate about the central axis with its face normal to the central axis, the stationary and rotating valve member having ports therein that come into and out of communication as the rotating valve member rotates.

16. The refrigeration apparatus of claim 15 including a spring mounting assembly mounting the stationary valve member disk into engagement with the rotating valve member disk.

17. Rotating magnetic refrigeration-heat pump apparatus comprising:

(a) an even number of magnetic regenerator beds, each bed including material that exhibits that magnetocaloric effect that is porous and allows the flow of heat transfer fluid through such magnetocaloric material, each bed having a hot end and a cold end, hot end input and output ports at the hot end of each bed, and cold end input and output ports at the cold end of each bed, the beds arranged in a circular ring with the cold end of each bed adjacent to the cold end of an adjacent bed and the hot end of each bed adjacent to the hot end of an adjacent bed, the adjacent cold ends of the beds open to each other for fluid flow and having one common cold end input port and one common cold end output port, the adjacent hot ends of the beds separated by flow-proof separators and having an input port and an output port for the hot end of each bed, the ring of magnetic regenerator beds mounted for rotation about a central axis and including a drive for driving the ring of beds in rotation about the central axis, wherein heat transfer fluid flowing from an input port to an output port of a bed flows circumferentially with respect to the central axis;

(b) at least one magnet providing a magnetic field that passes through at least one but not all of the regenerator beds in the ring so that at least one bed is in the magnetic field and at least one bed is outside of the magnetic field;

(c) a rotary distribution valve comprising an inner stationary valve member and an outer rotating valve member that is mounted to rotate in engagement with the stationary valve member about the central axis, the stationary valve member having two cold fluid chambers and two hot fluid chambers, the rotating valve member having first cold fluid ports therein that as the rotating valve member rotates are successively in communication with the first cold fluid chamber, second cold fluid ports therein that, as the rotating valve member rotates, are successively in communication with the second cold fluid chamber, the rotating valve member further having first hot fluid ports that, as the rotating valve member rotates, are successively in communication with the first hot fluid chamber, and second hot fluid ports that, as the rotating valve member rotates, are successively in communication with the second hot fluid chamber, and channels in the stationary valve member extending from two hot fluid openings to the first and second hot fluid chambers and from two cold fluid openings to the first and second cold fluid chambers;

(d) conduits extending from the cold input ports of the beds to the ports in the rotating valve member that come successively in communication with the first of the cold fluid chambers, and conduits extending from the cold output ports of the beds to the ports in the rotating valve member that come successively in communication with the second of the cold fluid chambers, conduits extending from the hot output ports of the beds to the ports in the rotating valve member that come successively in communication with the first of the hot fluid chambers, and conduits extending from the hot input ports of the beds to the ports of the rotating valve member that come successively in communication with the second of the hot fluid chambers;

(e) a hot heat-exchanger with an inlet and an outlet;

(f) a cold heat-exchanger with and inlet and an outlet;

(g) conduits extending from the outlet of the cold heat exchanger to a cold fluid opening of the stationary valve member that is in communication with the first cold fluid chamber, and conduits extending from the inlet of the cold heat exchanger to a cold fluid opening of the stationary valve member that is in communication with the second cold fluid chamber, and conduits extending from a hot fluid opening of the stationary valve member in communication with the first hot fluid chamber to the inlet of the hot heat exchanger via a pump, and conduits extending from the outlet of the hot heat exchanger to a hot fluid opening in the stationary valve member in communication with the second hot fluid chamber in the stationary valve member; and

(h) a pump connected in the conduits to drive heat transfer fluid in a circuit through the hot and cold heat exchangers, the conduits, the beds and the distribution valve.

18. The refrigeration apparatus of claim 17 wherein the stationary valve member has a top end and a bottom end and wherein the cold fluid openings in the stationary valve member face axially at one of the ends and the hot fluid openings in the stationary valve member face axially at the other end.

19. The refrigeration apparatus of claim 17 wherein the magnet comprises a permanent magnet.

20. The refrigeration apparatus of claim of 19 wherein the magnet is C-shaped.

21. The refrigeration apparatus of claim 17 further including a mounting platform mounted for rotation about the central axis, the conduits that extend from the rotating valve member to the beds having sections extending from the mounting platform to the ring of beds, the ring of beds supported by the mounting platform for rotation about the central axis.

22. The refrigeration apparatus of claim 21 wherein the conduit sections extending from the mounting platform to the beds providing physical support for the ring of beds.

23. The refrigeration apparatus of claim 21 wherein the outer rotating valve member and the mounting platform are connected together to rotate together about the central axis.