A refrigerator appliance includes a fresh food working fluid circuit that couples a hot side heat exchanger, a fresh food cold side heat exchanger and a fresh food regenerator. A first pair of diverter valves and a hot side reservoir are coupled to the fresh food working fluid circuit. The hot side reservoir is positioned below one or both of the first pair of diverter valves. A freezer working fluid circuit couples a freezer cold side heat exchanger and a freezer regenerator. A second pair of diverter valves and a fresh food cold side reservoir are coupled to the freezer working fluid circuit. The fresh food cold side reservoir is positioned below one or both of the second pair of diverter valves. A liquid-liquid heat exchanger is also coupled to the fresh food working fluid circuit.

A process for liquefying hydrogen gas into liquid hydrogen that includes: continuously introducing hydrogen gas into an active magnetic regenerative refrigerator module, wherein the module has one, two, three or four stages, wherein each stage includes a bypass flow heat exchanger that receives a bypass helium heat transfer gas from a cold side of a low magnetic or demagnetized field section that includes a magnetic refrigerant bed at a hydrogen gas first cold inlet temperature and discharges hydrogen gas or fluid at a first cold exit temperature; wherein sensible heat of the hydrogen gas is entirely removed by the bypass flow heat exchanger in the one stage module or a combination of the bypass flow heat exchangers in the two, three or four stage module, the magnetic refrigerant bed operates at or below its Curie temperature throughout an entire active magnetic regeneration cycle, and a temperature difference between the bypass helium heat transfer first cold inlet temperature and the hydrogen gas first cold exit temperature is 1 to 2 K for each bypass flow heat exchanger.

This invention relates to magnetocaloric materials comprising alloys useful for magnetic refrigeration applications. In some embodiments, the disclosed alloys may be Cerium, Neodymium, and/or Gadolinium based compositions that are fairly inexpensive, and in some cases exhibit only 2.sup.nd order magnetic phase transitions near their curie temperature, thus there are limited thermal and structural hysteresis losses. This makes these compositions attractive candidates for use in magnetic refrigeration applications. Surprisingly, the performance of the disclosed materials is similar or better to many of the known expensive rare-earth based magnetocaloric materials.

A method for forming a caloric regenerator includes depositing layers of additive material. The additive material includes a caloric material. The method also includes joining the layers of additive material to one another. After joining the layers of additive material, the caloric regenerator includes a regenerator body that extends longitudinally between a hot end portion and a cold end portion. A working fluid is flowable through the regenerator body between the hot and cold end portions of the regenerator body. The layers of additive material are deposited such that one or more of a cross-sectional area of the regenerator body, a void fraction of the regenerator body, a characteristic size of the caloric material, and a composition of the caloric material varies along a length of the regenerator body between the hot and cold end portions of the regenerator body.

A refrigerator appliance includes a fresh food working fluid circuit that couples a hot side heat exchanger, a fresh food cold side heat exchanger and a fresh food regenerator. A first pair of diverter valves and a hot side reservoir are coupled to the fresh food working fluid circuit. The hot side reservoir is positioned below one or both of the first pair of diverter valves. A freezer working fluid circuit couples a freezer cold side heat exchanger and a freezer regenerator. A second pair of diverter valves and a fresh food cold side reservoir are coupled to the freezer working fluid circuit. The fresh food cold side reservoir is positioned below one or both of the second pair of diverter valves. A liquid-liquid heat exchanger is also coupled to the fresh food working fluid circuit.

A refrigeration apparatus (1) includes a main refrigerant circuit (2) including a positive displacement compressor (4), a condenser (6), an expansion valve (8), and an evaporator (10), through which a refrigerant circulates successively in a closed loop circulation, a lubrication refrigerant line (18) connected to the main refrigerant circuit (2) between the condenser (6) and the expansion valve (8) or to the condenser (6), in which circulates a portion of the refrigerant of the main refrigerant circuit (2) and connected to the compressor (4) for lubrication of said compressor (4) with the refrigerant, at least one lubrication refrigerant storing cavity (70) connected to the lubrication refrigerant line (18), the lubrication refrigerant storing cavity (70) being configured to store liquid refrigerant for lubrication of the compressor (4) said at least one lubrication refrigerant storing cavity (70) being provided within the compressor (4).

Magnetocaloric refrigerator or heat pump comprising an externally activatable thermal switch for transferring heat from a heat source to a heat sink, comprising: an insulator cage with thermally conductive windows for the source and sink; a magnetic nanofluid, comprised within said cage, wherein said magnetic nanofluid is able to flow under a magnetic field inside the insulator cage between a contact of the thermally conductive window of the heat source and a contact of the thermally conductive window of the heat sink; and a activatable magnet placed at either one of the thermally conductive windows, such that the produced magnetic field is aligned substantially parallel to the temperature gradient from heat source to heat sink. The apparatus alternates between: activating the magnet, such that the nanofluid flows to establish a thermal contact with the thermal source but not with the sink; deactivating the magnet, such that the nanofluid flows to establish a thermal contact with the thermal sink but not with the source.

Process of refrigeration induced by an external stimulus comprising the application of an external stimulus selected among hydrostatic pressure, uniaxial pressure, electric field and illumination with light, to an organic-inorganic hybrid material of crystalline structure with hexagonal packing, of formula ABX.sub.3 (I), where A is a given monovalent organic cation or a given mixture of monovalent organic cations or a given mixture of monovalent organic cations and monovalent inorganic cations, B is a given divalent metal cation, a given mixture of divalent metal cations, or a given 50/50% atomic mixture of a monovalent cation and a trivalent cation, and X is a halide anion or a mixture thereof. A device with cooling capacity induced by an external stimulus, comprising the above organic-inorganic hybrid material.

A process is disclosed for producing a magnetocaloric composite material for a heat exchanger. The process comprises the following steps: Providing (S110) a plurality of particles (110) of a magnetocaloric material in a shaped body (200) and immersing the plurality of particles (110) present in the shaped body (200) into a bath in order to coat the particles by a chemical reaction and bond them to one another.

A magnetic refrigerator includes a magnetic working substance, and a magnetic field application unit that causes a relative movement with respect to the magnetic working substance in a first direction and applies a magnetic field to the magnetic working substance. The magnetic field application unit includes magnetic poles arranged on one side of the magnetic working substance in a second direction orthogonal to the first direction, and spaced from each other in a third direction orthogonal to the first and second directions of the magnetic working substance. A refrigeration apparatus includes the magnetic refrigerator and a heating medium circuit to exchange heat with the magnetic refrigerator.