Magnetocaloric heat generator

A magnetocaloric heat generator (1, 10, 100, 1′, 1″) comprising

• at least one assembly of at least two magnetocaloric modules (2, 3, 4, 5, 2′, 3′), the at least two magnetocaloric modules being connected serially, each of the at least two magnetocaloric modules having a hot end and a cold end and at least two magnetocaloric sub-modules (21, 31, 41, 42, 43, 51, 52, 53, 21′, 31′) including each at least two magnetocaloric stages,
• the magnetocaloric heat generator having a hot heat exchanger (71) and a cold heat exchanger (61),
• wherein each magnetocaloric module comprises at least one circulating member,
• a heat transfer fluid is circulated by the at least one circulating member (212, 312, 412, 512, 422, 212′, 312′) through each of the at least two magnetocaloric modules, each of the at least two magnetocaloric modules (2, 3, 4, 5, 2′, 3′) comprises at least two magnetocaloric stages (210, 211, 310, 311, 410, 411, 420, 421, 430, 431, 510, 511, 520, 521, 530, 531, 610, 610′, 611, 611′, 710, 710′, 711, 711′) of magnetocaloric material, the at least two magnetocaloric stages being in opposite magnetic phases, such that when one of said at least two magnetocaloric stages undergoes a temperature rise due to the application of a magnetic field, the other of the at least two magnetocaloric stages undergoes a temperature drop due to removing or reduction of the magnetic field,
• the at least one heat transfer fluid circulating member (212, 312, 412, 512, 422, 212′, 312′) is in fluidic communication with the at least two magnetocaloric stages of each of the magnetocaloric modules and each of the at least one circulating member is connected between consecutive ends of the said at least two magnetocaloric stages of a corresponding magnetocaloric module of the at least two magnetocaloric modules, wherein said magnetocaloric stages of said corresponding magnetocaloric module have opposite magnetic phases, such that the heat transfer fluid flows through each of said magnetocaloric stages of said corresponding magnetocaloric module in opposite directions,
• the at least two magnetocaloric stages (210, 211, 310, 311, 410, 411, 420, 421, 430, 431, 510, 511, 520, 521, 530, 531, 610, 610′, 611, 611′, 710, 710′, 711, 711′) are made of magnetocaloric materials arranged so that magnetocaloric effect is the same in all of the at least two magnetocaloric stages,
• the cold ends (F2, F3, F4, F5, F6, F7) of the magnetocaloric modules (2, 3, 4, 5, 2′, 3′) are in fluidic communication via a cold transfer circuit (6) comprising the cold heat exchanger (61) through which the heat transfer fluid flows and exchanges heat with an first external circuit,
• the hot ends (C2, C3, C4, C5, C6, C7) of the magnetocaloric modules (2, 3, 4, 5, 2′, 3′) are in fluidic communication via a hot transfer circuit (7) comprising the hot heat exchanger (71) through which the heat transfer fluid flows and exchanges heat with an second external circuit, and
• the heat exchangers (61, 71) of the cold and the hot transfer circuits are constructed so that differences of inlet and outlet temperatures of the heat transfer fluid in each of the cold and the hot heat exchangers (61, 71) of the cold and the hot transfer circuits (6, 7) is equal to the temperature jump of each magnetocaloric stage (210, 211, 310, 311, 410, 411, 420, 421, 430, 431, 510, 511, 520, 521, 530, 531, 610, 610′, 611, 611′ 710, 710′, 711, 711′) when the magnetic phase of each magnetocaloric stage changes.

A magnetocaloric heat generator comprising:

• at least one assembly of at least two magnetocaloric modules connected serially, each of the at least two magnetocaloric modules having a hot end and a cold end, the magnetocaloric heat generator having a hot heat exchanger and a cold heat exchanger;
• wherein each magnetocaloric module comprises at least one circulating member, a heat transfer fluid, circulated by the at least one circulating member, flowing through each of the at least two magnetocaloric modules, each of the magnetocaloric modules comprises at least two magnetocaloric stages being in opposite magnetic phase with respect to each other such that when one of said at least two magnetocaloric stages undergoes a temperature rise due to application of a magnetic field, another of the at least two magnetocaloric stage undergoes a temperature drop due to removing or reduction of the magnetic field,
• the at least one circulating member being in fluidic communication with the at least two magnetocaloric stages of each of the at least two magnetocaloric modules and each of the at least one circulating member is connected between ends of the said magnetocaloric stages of a corresponding magnetocaloric module of the at least two magnetocaloric modules, wherein said magnetocaloric stages of said corresponding magnetocaloric module have opposite magnetic phases such that the heat transfer fluid flows through each of said magnetocaloric stages of said corresponding magnetocaloric module in opposite directions,
• the magnetocaloric stages are made of magnetocaloric materials arranged so that a magnetocaloric effect is the same in all of the magnetocaloric stages,
• the cold ends of the at the least two magnetocaloric modules are in fluidic communication via a cold transfer circuit used by the heat transfer fluid and comprising the cold heat exchanger for a heat exchange with a first external circuit,
• the hot ends of the at the least two magnetocaloric modules are in fluidic communication via a hot transfer circuit used by the heat transfer fluid and comprising the hot heat exchanger for a heat exchange with a second external circuit, and
• the cold heat exchanger and the hot heat exchanger are arranged so that the difference of inlet and outlet temperature of the heat transfer fluid in each of the cold heat exchanger and the hot heat exchanger is at most forty percent of the magnetocaloric effect applied to each of the at least two magnetocaloric stages.