Magnetocaloric thermal generator

摘要

A heat generator (10) which comprises magnetocaloric elements (2) that are arranged in a circle about a central axis. A magnetic arrangement (3) of alternating magnetized and non-magnetized zones (4, 5), that is located within the circle formed by the magnetocaloric elements (2), is rotatable around the central axis and co-operates with a field closing device (6) to loop magnetic flux generated by the magnetic arrangement (3) and alternately subject the magnetocaloric elements (2) to a magnetic field variation and create, alternately in each magnetocaloric element (2), heating and cooling cycles, in synchronization with the circulation of heat transfer fluid which flows through the magnetocaloric elements (2) during the heating and cooling cycles. The field closing device (6) comprises a heat insulation (9).

主权项

1. A heat generator (1, 10, 20) comprising:
a plurality of magnetocaloric elements (2) being arranged in a circumferential arrangement around a central axis (A) and being subjected to a variable magnetic field for facilitating creation of alternating heating and cooling cycles in each of the magnetocaloric elements; a magnetic arrangement (3) comprising alternating magnetized zones (4) and non magnetized zones (5), the magnetic arrangement being rotatable around the central axis (A) for generating the variable magnetic field, and the magnetic arrangement (3) being completely located radially inside the circumferential arrangement defined by the magnetocaloric elements (2); an annular field closing device (6) being arranged around and surrounding the circumferential arrangement of the magnetocaloric elements (2) and concentric with respect to the magnetic arrangement such that, upon rotation of the magnetic arrangement, a magnetic flux generated by the magnetized zones being sequentially looped through the magnetocaloric elements to alternately subject each of the magnetocaloric elements to a magnetic field variation and alternately create the heating cycle and the cooling cycle in each of the magnetocaloric elements, in synchronization with circulation of at least one heat transfer fluid which passes through the magnetocaloric elements during the heating and the cooling cycles; wherein the annular field closing device comprises:
a heat insulation means;a layer of at least one magnetically conductive sheet metal strip that is coiled on itself with a layer of a heat insulating material between successive coil turns of the layer of the at least one magnetically conductive sheet metal strip,the layer of the at least one magnetically conductive sheet metal strip and the layer of a heat insulating material therebetween form an annulus comprising a plurality of concentric, radially alternating layers of the magnetically conductive and the heat insulating material; andthe layer of the at least one magnetically conductive sheet metal strip comprising at least partly either iron, an iron alloy, or a magnetically conductive metal alloy including either cobalt or silicon; and the annular field closing device completely radially surrounding the circumferential arrangement of the magnetocaloric elements (2) such that the magnetocaloric elements are located radially within the annular field closing device.