MAGNETOCALORIC HEAT GENERATOR

• US 20110314836A1
• Filed: 03/16/2010
• Published: 12/29/2011
• Est. Priority Date: 03/20/2009
• Status: Active Grant

• Current Assignee: Magnoric
• Original Assignee: Cooltech Applications S.A.S.
• Inventors: Heitzler, Jean-Claude, Muller, Christian
• Granted Patent: US 9,134,051 B2
• Time in Patent Office: Days
• 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 2321/002 by using magneto-caloric effects
• CPC Class Codes: Y02B 30/00 Energy efficient heating, ventilation or air conditioning [HVAC]

Abstract

A magnetocaloric heat generator (1) which comprises a driving mechanism (26) in fluidic connection with first and second ends (3 and 4) of a thermal module (2) via at least one heat exchange mechanism (7, 27) so that the heat transfer fluid circulates in a closed constant-volume fluidic circuit through the magnetocaloric heat generator (1).

Claims

1-6. -6. (canceled)

7. A magnetocaloric heat generator (1, 10) comprising:

at least one thermal module (2, 20) having first and second ends (3, 4) and comprising at least one magnetocaloric element (5);

a magnetic arrangement for subjecting the magnetocaloric element (5) to a variable magnetic field and alternately creating, in the magnetocaloric element (5), a heating phase and a cooling phase;

a means for circulation (26, 16) of a heat transfer fluid in thermal contact with the magnetocaloric element (5) and circulating alternately towards the one (3) of the first and the second ends, and then towards the other (4) of the first and the second ends and vice-versa, in synchronisation with a variation of the magnetic field; and

at least one heat exchange means (7, 27) for transferring the thermal energy produced by the thermal module (2, 20) to at least one device external to the heat generator (1, 10);

wherein the heat transfer fluid driving means (26, 16) is in fluidic communication, in a closed constant-volume fluidic circuit, with both the first and the second ends (3 and 4) of the thermal module (2, 20) through the exchange means (7, 27); and

the heat exchange means (7, 27) comprises first and second exchange areas (8 and 9, 28 and 29) distinct from one another, connected in parallel, and equipped with control means (11) for the direction of circulation of the heat transfer fluid, so that each of them is crossed alternately in only one direction of circulation.

8. The heat generator according to claim 7, wherein an inlet (12) of the first exchange area (8, 28) and an outlet (15) of the second exchange area (9, 29) of the thermal exchange means (7, 27) are in fluidic communication with a corresponding one of the first and the second ends (3, 4) of the thermal module (2, 20) and an outlet (13) of the first exchange area (8, 28) and an inlet (14) of the second exchange area (9, 29) are in fluidic communication with one another and with the driving means (26, 16).

9. The heat generator according to claim 8, wherein the driving means is a piston (6) of a double-acting jack with two chambers (17, 18) each in fluidic communication with one of the first and the second ends (3 or 4) of the thermal module (2) through the heat exchange means (7, 27).

10. The heat generator according to claim 8, in which the thermal module (20) comprises at least first and second magnetocaloric elements (5) in fluidic connection through a common cell (19), each of the first and second magnetocaloric elements (5) is subjected to a different heating or cooling phase and crossed by the heat transfer fluid in opposite directions, wherein the driving means (16) includes:

one central actuator (21) in fluidic connection with the common cell (19), and first and second end actuators (22 and 23), each in fluidic connection with one of the first and the second ends (3 or 4) of the thermal module(20).

11. The heat generator according to claim 10, wherein the central actuator (21) and the first and the second end actuators (22, 23) comprise pistons that are controlled by a same control device.

12. A process for exchange of the thermal energy produced by a heat generator (1, 10) which comprises at least one thermal module (2, 20) having first and second ends (3, 4) and comprising at least one magnetocaloric element (5);

a magnetic arrangement for subjecting the magnetocaloric element (5) to a variable magnetic field and alternately creating, in the magnetocaloric element (5), a heating phase and a cooling phase;

a means for circulation (26, 16) of a heat transfer fluid in thermal contact with the magnetocaloric element (5) and circulating alternately towards the one (3) of the first and the second ends, and then towards the other (4) of the first and the second ends and vice-versa, in synchronisation with a variation of the magnetic field; and

at least one heat exchange means (7, 27) for transferring the thermal energy produced by the thermal module (2, 20) to at least one device external to the heat generator (1, 10);

wherein the heat transfer fluid driving means (26, 16) is in fluidic communication, in a closed constant-volume fluidic circuit, with both the first and the second ends (3 and 4) of the thermal module (2, 20) through the exchange means (7, 27); and

the heat exchange means (7, 27) comprises first and second exchange areas (8 and 9, 28 and 29) distinct from one another, connected in parallel, and equipped with control means (11) for the direction of circulation of the heat transfer fluid, so that each of them is crossed alternately in only one direction of circulation, the process comprising the steps of;

moving the heat transfer fluid, step by step, in the magnetocaloric element (5), at every operating phase, by a driving means (26, 16) connected to heat exchange means (7, 27) in a closed constant-volume fluidic circuit;

exchanging the thermal energy produced by the heat generator, at every operating phase, and transported by the heat transfer fluid, at every magnetocaloric cycle, comprising a heating phase and a cooling phase in two successive exchange areas (8, 9 and 28, 29) of each thermal exchange means (7, 27).