Multi-Material-Blade for Active Regenerative Magneto-Caloric and Electro-Caloric Heat Engines

• US 20140216057A1
• Filed: 06/29/2012
• Published: 08/07/2014
• Est. Priority Date: 06/30/2011
• Status: Active Grant

• Current Assignee: Camfridge Ltd.
• Original Assignee: Camfridge Ltd.
• Inventors: Wilson, Neil, Oezcan, Sibel, Burdett, Paul
• Granted Patent: US 10,222,099 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

The present invention describes the design and fabrication of Multi-Material-Blades used as active regenerative regenerators in active regenerative magneto-caloric or electro-caloric engines. The blades consist of a plurality of elements (2) that divide the blade body along its length. Each element (2) is made of a different magneto-caloric or electro-caloric material selected appropriately, and a plurality of dedicated channels (3) penetrates the blade body (1) and extends along the length of the blade. The dedicated channels (3) can be provided with fluid mixing structures, porous layers or hydrophobic coatings to reduce the HE loss in an active regenerative engine. The Multi-Material-Blades are obtainable by ink jet printing techniques to reduce costs. The Multi-Material-Blades can further have a curved shape to form an involute blade body (1). All measures can improve the performance of active regenerative magneto-caloric or electro-caloric engines, and lay the basis for commercial solutions.

Claims

1. Multi-Material-Blade for use in an active regenerative magneto-caloric or electro-caloric engine, the blade comprising

a blade body (1) made from a plurality of elements (2) made from different magneto-caloric or electro-caloric materials, wherein the blade body (1) is divided along its length into said plurality of elements (2);

a plurality of dedicated channels (3), which penetrate the blade body (1) and extend along the length of the blade,

wherein each of the plurality of dedicated channels (3) is provided with a fluid mixing structure (6, 11, 13) and/or each of the plurality of dedicated channels (3) is provided with a hydrophobic coating layer (12).

7. Multi-Material-Blade according to claim 1, wherein

each of the plurality of elements (2) is made from a magneto-caloric material preferably selected from the group of LaFeSi, LaFeSiCo, LaFeSiH, MnPFeAs, MnPFeSi, MnAsSb, MnPFeGe, Gd, GdDy, CoMnSi, CoMnGe, and GdSiGe, or electrocaloric material P(VDF-TrFE-chlorofluoroethylene), PLZT (8/65/35), Pb(Mg1/2Nb2/3)O3-35PbTiO3 (PMN-35PT)), BaTiO3, or (NH4)2SO4, that may additionally be provided with one or more dopants, wherein each material has a different Curie temperature, and each material has a porosity of 20% or less in respect to its volume.

8. Multi-Material-Blade according to claim 1, wherein

each of the plurality of elements (2) has a thermal conductivity in a range of 0.1 W/mK to 30 W/mk, preferably 0.1 W/mK to 10 W/mk, more preferably 0.1 W/mK to 5 W/mk, most preferably 0.1 W/mK to 2 W/mk.

9. Multi-Material-Blade according to claim 7, wherein

said plurality of elements (2) are designed and arranged such that the Curie temperature of the materials trace a temperature gradient established along the blade body (1) in an active regenerative magneto-caloric engine.

10. Multi-Material-Blade according to claim 1, wherein

each of the plurality of elements (2) is formed by a plurality of plates (4), and

the plurality of plates (4) are stacked on top of each other and are separated from each other by at least one spacer (5), preferably printed with ink jet printing techniques ink jet printing techniques, stencil or screen printing, photolithography, or direct application by dotting or jetting system, wherein the separations between the plurality of plates (4) forms the plurality of dedicated channels (3).

11. Multi-Material-Blade according to claim 10, wherein

the spacer (5) is a porous material with a porosity of greater than 25% in respect to its volume, the porous material being preferably at least one of collagen-glycosaminoglycan, collagen foam, polytetrafluoroethylene, spontex, and hydroxyapatite ceramic.

12. Multi-Material-Blade according to claim 10, wherein

each of the plurality of plates (4) has a thickness in a range of 50 μ

m to 1500 μ

m, preferably 60 μ

m to 700 μ

m, more preferably 70 μ

m to 350 μ

m, and

the at least one spacer (5) has a thickness in a range of 5 μ

m to 100 μ

m, preferably 10 μ

m to 75 μ

m, more preferably 15 μ

m to 60 μ

m.

13. Multi-Material-Blade according to claim 10, wherein

a surface texture (6) is provided at least on top of each of the plurality of plates (4) as fluid mixing structure (6), and/or

a hydro-phobic coating layer is provided to each of the plurality of plates (4), wherein preferably a glass layer is provided beneath each hydro-phobic coating layer.

14. Multi-Material-Blade according to claim 13, wherein the surface texture (6) is printed by ink printing techniques, or is formed from sand or a sand-like material that is glued to the plurality of plates (4).

15. Multi-Material-Blade according to claim 1, wherein

each of the plurality of elements (2) is formed by a perforated plate (7), wherein a plurality of perforations (9) in the perforated plates (7) form the plurality of dedicated channels (3).

16. Multi-Material-Blade according to claim 15, wherein

the plurality of perforations are a plurality of round and/or angular holes (9), wherein a diameter or width of each of the plurality of holes (9) is in a range of 10 μ

m to 150 μ

m, preferably 20 μ

m to 85 μ

m, and

a distance between adjacent ones of the plurality of holes (9) is in a range of 60 μ

m to 2 mm, preferably 80 μ

m to 600 μ

m.

17. Multi-Material-Blade according to claim 15, wherein

a symmetry breaker (13) is inserted as fluid mixing structure into each of the plurality of holes (9) and/or

an inner wall of each of the plurality of holes (9) has a rough surface (11) that serves as fluid mixing structure and/or

the inner wall of each of the plurality of holes (9) is provided with a hydrophobic coating layer (12), which is preferably a glass hydro-phobic coating layer.

18. Multi-Material-Blade according to one of the claims according to claim 10, wherein separators are provided between adjacent ones of the plurality of elements, in order to compensate for local temperature gradients at the interfaces of the plurality of elements in an active regenerative magneto-caloric engine, wherein the separators have a lower thermal conductivity than that of the magneto-caloric or electro-caloric materials, and have a preferred thickness in the range of 50 um to 1000 um.

2. Multi-Material-Blade for use in an active regenerative magneto-caloric or electro-caloric engine, the blade comprising

a blade body (1) made from a plurality of elements (2) made from different magneto-caloric or electro-caloric materials, wherein the blade body (1) is divided along its length into said plurality of elements (2);

a plurality of dedicated channels (3), which penetrate the blade body (1) and extend along the length of the blade,

wherein the cross-section of the blade-body (1) perpendicular to the dedicated channels (3) has along a predetermined direction a plurality of regions of different porosity, wherein at an interface of adjacent regions the porosity changes abruptly by at least 10%.

3. Multi-Material-Blade for use in an active regenerative magneto-caloric or electro-caloric engine, the blade comprising

a blade body (1) made from a plurality of elements (2) made from different magneto-caloric or electro-caloric materials, wherein the blade body (1) is divided along its length into said plurality of elements (2);

a plurality of dedicated channels (3), which penetrate the blade body (1) and extend along the length of the blade,

wherein each of the plurality of elements (2) is obtainable using ink jet printing techniques, stencil or screen printing, photolithography, or direct application by dotting or jetting system.

4. Multi-Material-Blade for use in an active regenerative magneto-caloric or electro-caloric engine, the blade comprising

a blade body (1) made from a plurality of elements (2) made from different magneto-caloric or electro-caloric materials, wherein the blade body (1) is divided along its length into said plurality of elements (2);

a plurality of dedicated channels (3), which penetrate the blade body (1) and extend along the length of the blade,

wherein each of the plurality of elements (2) has a curved shape so that the plurality of elements (2) form an involute blade body (1).

5. Multi-Material-Blade for use in an active regenerative magneto-caloric or electro-caloric engine, the blade comprising

a blade body (1) made from a plurality of elements (2) made from different magneto-caloric or electro-caloric materials, wherein the blade body (1) is divided along its length into said plurality of elements (2);

a plurality of dedicated channels (3), which penetrate the blade body (1) and extend along the length of the blade,

wherein each of the plurality of elements (2) in the blade body (1) is rotated in respect to its adjacent elements (2), preferably rotated by 90°

.

6. Multi-Material-Blade for use in an active regenerative magneto-caloric or electro-caloric engine, the blade comprising

a blade body (1) made from a plurality of elements (2) made from different magneto-caloric or electro-caloric materials, wherein the blade body (1) is divided along its length into said plurality of elements (2);

a plurality of dedicated channels (3), which penetrate the blade body (1) and extend along the length of the blade,

wherein the magneto-caloric or electro-caloric materials have a figure of merit greater than that of gadolinium,

wherein the cooling capacity is maximised along the length of the blade body (1), and wherein the cooling capacity at a boundary between two elements (2) along the blade body (1) matches within 30%, and where the lowest cooling capacity in an element (2) is located at one end of the element, and where the cooling capacity of each element (2) rises at a rate proportional to the temperature gradient established along that particular element (2) of the blade body (1) in an active regenerative magneto-caloric or electro-caloric engine.

19. Method for fabricating a Multi-Material-Blade for use in an active regenerative magneto-caloric or electro-caloric engine, comprising the steps of

forming a blade body (1) from a plurality elements (2) made from different magneto-caloric or electro-caloric materials, wherein the plurality of elements (2) are arranged along the length of the blade body (1);

forming a plurality of dedicated channels (3), which penetrate the blade body (1) and extend along the length of the blade body (1);

providing each of the plurality of dedicated channels (3) with a fluid mixing structure (6, 11, 13) and/or a hydrophobic coating layer (12).

20. Method for fabricating a Multi-Material-Blade for use in an active regenerative magneto-caloric or electro-caloric engine, comprising the steps of

forming a blade body (1) from a plurality elements (2) made from different magneto-caloric or electro-caloric materials, wherein the plurality of elements (2) are arranged along the length of the blade body (1);

forming a plurality of dedicated channels (3), which penetrate the blade body (1) and extend along the length of the blade body (1);

wherein each of the plurality of elements (2) is formed by stacking a plurality of plates (4) on top of each other, wherein the plurality of plates (4) are separated from each other by at least one spacer (5) printed with ink jet printing techniques, and clamping and/or gluing together the plurality of plates (4),

wherein each of the plurality of plates (4) is formed by aligning sub-plates (16) made of a magneto-caloric or electro-caloric material in a frame (17), applying strips and/or dots (18) to the sub-plates (16), and baking the aligned sub-plates (16) and the frame (17) to form the plurality of plates (4).