HEAT EXCHANGER ELEMENTS AND DIVICES

Abstract

A heat exchanging element. The heat exchanging element is comprised of a plurality of spaced-apart through a common barrier, plates. The plates are capable of transmitting heat from a first end of said plates in contact with a heat source on one side of the common barrier, directly to a second end of the plates that are in contact with a heat sink on the opposite side of the common barrier.

Description

BACKGROUND OF THE INVENTION

Most heat exchangers are made from metals such as brass, copper, aluminum, stainless steel or titanium. Comparatively speaking, these metals are heavy and are subject to corrosion when used in oxidizing environments. Also, these metals have relatively low thermal conductivity when compared to a material such as graphene sheets. Therefore, a heat exchanger utilizing graphene sheet heat transfer plates is especially useful for compact, high efficiency, high temperature, or corrosive fluid applications or applications where weight is of concern.

Heat exchangers based on graphene thermal transfer media are well known, especially solid/gas heat exchangers. The only example of plate type liquid based heat exchangers is U.S. Patent Publication 2015/0083381. It only uses graphene to conduct heat across a plastic membrane. There is no art found in which the heat transfer material is a sheet of pressed graphene taking advantage of the high thermal differential between in-plane and through-plan thermal conductivity.

Other patent and publication disclosures that the patentees are aware of include, U.S. Pat. No. 8,269,098 which discloses a fin formed of carbon composite materials, i. e. graphene. U.S. Patent Publication 2014/0060087 deals with a heat radiation-thermoelectric fin which includes a heterogeneous laminate of graphene and a thermoelectric inorganic material.

U.S. Pat. No. 6,538,892 deals with a radial finned heat sink assembly for electrical component that has planar fins with graphite layers aligned with plane of the fin so that thermal conductivity in a direction parallel to the plane is greater than that in a perpendicular direction.

Publication WO2009/142924 deals with electrodes. The transition metal catalyst may merge with the ductile metallic layer. Then, the electrode is cooled. Upon cooling, the graphene planes are anchored in the ductile metallic layer. The soft and fusible metallic layer provides a bonding interface between the current collector and the graphene planes.

U.S. Patent publication 2012/0285660 deals with a heatsink e.g., a car radiator, that has a heat exchange device having several heat exchange elements in branched configuration and a flat base that is configured to interface with a heat source.

THE INVENTION

Thus, what is disclosed and claimed herein is a heat exchanging element. The heat exchanging element is comprised of a plurality of spaced-apart through a common wall, plates. The plates are capable of transmitting heat from a first end of said plates in contact with a heat source on one side of the common wall, directly to a second end of the plates that are in contact with a heat sink on the opposite side of the common wall.

In a second embodiment, there is the use of such a heat exchanging element in a heat exchanger device.

The instant invention is, in one embodiment, a heat exchanger based on the use of heat plates or fins made for the purpose with specially formulated 2-dimensional thermal conductive sheets or paper made of 2-dimensional thermal conductive materials. Liquid-liquid, liquid—gas or gas-gas heat exchangers may have fins or heat exchanger plates to conduct heat between hot and cold sides of the device. Two-dimensional thermal conductive of sheet or paper have very high thermal conductivity in the direction of the plane and more limited thermal conductivity transverse to the plane of the graphene sheet. An exchanger based on 2-dimensional thermal conductive sheets is, therefore, more uniform in temperature across the entire device, which results in high overall efficiency and lack of relatively hot and cold spots. This allows a more compact design and a better device for heat sensitive fluids or for applications requiring precise temperature ranges. Two-dimensional thermal conductive sheets have high resistance to acids, bases, and solvents making such heat exchangers useful for extreme working fluids or corrosive gases.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a full front view of an illustration of a thermal conductive element of this invention.

FIG. 2 is a full front illustration of a curved thermal conductive element of this invention.

FIG. 3 is an illustration in perspective of a circular heat exchanging element with two heat transfer plates inserted longitudinally through the wall of the tube.

FIG. 4 is an illustration of a full end view of the heat exchanging element of FIG. 3.

FIG. 5 is an illustration of a full end view of a heat exchanger of the tube and shell type with hot fluids flowing through a single circular heat exchanging element.

FIG. 6 is an illustration of a full end view of a heat exchanger with hot fluids flowing through two circular heat exchanging elements.

FIG. 7 is an illustration of a full side view of a rectangular heat exchanger with a heat exchanging element separating hot and cold zones.

FIG. 8 is an illustration of a full side view of an example of two rectangular heat exchanger assembly in series by stacking.

FIG. 9A is a side view of a plate type heat exchanger with heat transfer plates penetrating the separator plates between hot and cold zones.

FIG. 9B is a front view of a plate type heat exchanger with heat transfer plates penetrating the separator plates between hot and cold zones.

FIG. 9C is a view in perspective of stacked plates of a plate type heat exchanger with heat transfer plates penetrating the separator plates between hot and cold zones.

FIG. 10 is an illustration of a full side view of a composite heat exchanger plate.

FIG. 11 is an illustration of a full top view of an example of a heat exchanger element with corrugated heat transfer plates to cause turbulent flow.

FIG. 12 is an illustration of a full top view of a heat exchanger element with heat transfer plates for laminar flow.

DETAILED DISCUSSION OF THE INVENTION

Most, if not all, industrial heat exchangers rely on the thermal conductivity of a metallic material to conduct heat in a direction that is transverse to the plane of the material, that is, through the wall of a tube or across a metal plate, for example. Instead of relying on this transverse thermal conductivity through the wall of material dividing the hot and cold zones, the instant invention makes use of specially constructed 2-dimensional thermal conductive heat exchanger plates or fins that are deployed in a manner in which they interpenetrate the hot and cold zones of a heat exchange device. This type of deployment is novel in that it contemplates the use of specially constructed heat exchange plates to take advantage of the high anisotropic thermal conductivity of the 2-dimensional thermal conductive materials heat exchanger plates across the plane of the materials, and it also exposes a much greater surface area to both hot and cold fluids, resulting in unexpectedly high heat transfer rates. The device is unexpectedly uniform in temperature and performance when compared to conventional heat exchangers, especially those typically used in corrosive environments. Additionally, the use of 2-dimensional thermal conductive materials heat exchanger plates to conduct heat, allows for the use of non-thermally conductive materials like plastics or composites for the structural components of the heat exchanger, which opens a wide range of possibilities to make these devices lighter, more resistant to corrosion, and smaller.

Graphene sheets, for example, can be manufactured in a manner that may or may not utilize binders and that include fillers tailored for specific purposes. These sheets have very high anisotropic thermal conductivity in the plane, but relatively low tensile or mechanical strength. They may also have low resistance to shear forces or surface abrasion, which can cause flaking and delamination of the graphene sheet. Therefore, the sheets may be reinforced to increase strength and resist flaking. The reinforcement may be a surface coating, a laminated sheet of another material, or internal materials such as fibers, or a combination of these reinforcements. Surface coatings may include polymeric or other coating materials specially selected to aid in heat transfer. Internal strengthening aids may include binders and metallic or ceramic fibers or other materials specially selected to improve heat transfer while adding strength. Lamination materials may include sheets of thermoplastic or thermoset materials, sheets of fabric, or sheets composed of metallic materials.

Turning now to the Figures, there is shown in FIG. 1 a full front view of an illustration of a thermal conductive element 1 of this invention. There is also shown heat transfer plates 2 penetrating through a barrier 3 that separates hot 4 and cold 5 zones. Barrier 3 can consist of spacers, gaskets, or solid plates that form a barrier to prevent fluid interchange between hot and cold zones.

The heat spreading heat transfer plate 2 are vertically aligned to a substrate by inserting the heat transfer plates 2 through the barrier 3 of the substrate. The heat transfer plates 2 are coated by the thermal heat conducting 2-dimensional material that is made of metal, ceramic, polymeric, carbonaceous, laminates, or composite materials. The heat transfer plates 2 are made of heat conducting plates of metals, ceramics, carbonaceous, laminates, or composite materials, The heat conducting plates and the barrier 3 are used to separate the hot and cold fluids in a heat exchanger. In one embodiment, the heat exchanger heat transfer plates 2 are made by laminating graphene-based thermal spreading sheets on both side of a substrate such as aluminum plate. Yet, in another embodiment, the heat transfer plates 2 are made by coating a graphene-based thermal ink on a substrate.

The heat exchanger device 1 can be made in many different configurations, depending on the intended end use, as shown in FIGS. 3 to 12, wherein there is shown a circular heat exchanger 6 wherein 7 and 7′ are heat transfer plates that are inserted longitudinally through the wall 8 of a tube 9, which becomes more clear by observing FIG. 4, which is full end view of the heat exchanging element of FIG. 3 showing the heat transfer plates 7/7′ penetrating the tube 9 wall.

FIG. 2 is a full front illustration of a curved thermal conductive element 10 of this invention showing the heat transfer plates 2 penetrating through a barrier 3 that separates hot 4 and cold 5 zones.

FIG. 5 is an illustration of a full end view of a heat exchanger 11 of the tube and shell type with hot fluids 4 flowing through a single circular heat exchanging element.

FIG. 6 is an illustration of a full end view of a heat exchanger 12 with hot fluids 4 flowing through two circular heat exchanging elements 13 and 14.

Turning now to FIG. 7, there is shown an illustration of a full side view of a rectangular heat exchanger 15 with a heat exchanging element 16 separating hot 4 and cold 5 zones. Shown are the hot inlet 16 and the hot outlet 17, along with a cold inlet 18 and a cold outlet 19. Also shown are the heat transfer plates 2 penetrating through the barrier 3.

FIG. 8 shows an example of two rectangular heat exchanges assemble in a series by stacking the. Thus, there is shown the hot inlet 16 and the hot outlet 17, along with a cold inlet 18 and a cold outlet 19. Also shown are the heat transfer plates 2 penetrating through the barrier 3. It should be noted that the hot outlet 17 and hot inlet 16 are joined together on one end as are the cold outlet 19 and the cold inlet 18.

FIGS. 9A, 9B, and 9C show an example of a plate type heat exchanger with heat transfer plates penetrating the barrier plates 3 between hot 4 and cold 5 zones. Thus, there is shown the heat transfer plates 2, the back plate, or barrier 3, and stacked plates 20.

FIG. 10 is an illustration of a composite heat exchanger plate 21, wherein 22 is graphite film, 23 is an adhesive, 24 is a barrier wall, 25 is additional adhesive, and 26 is graphite leaf. The plate is surrounded by a polymeric coating 27.

FIG. 11 shows an illustration showing a top view of a heat exchanger element 28 with corrugated heat transfer plates 29 to cause turbulent flow in the heat exchanger.

Finally, FIG. 12 is an illustration of a heat exchanger element 30 with heat transfer plates 31 for laminar flow in the heat exchanger.

The heat exchanger plates are made by laminating 2-dimensional thermal conductive materials onto thermal spreading sheets on both sides of a substrate such as aluminum plate. In another embodiment, the heat transfer plates are made by coating of a 2-dimensional thermal conductive thermal ink on a substrate.

Claims

1. A heat exchanging element, said heat exchanging element comprising a plurality of spaced-apart heat transfer plates wherein the said plates are assembled in a manner that heat is transferred from a first end of said plates in contact with a heat source on one side of a barrier that separates hot and cold zones, directly to a second end of said plates that are in contact with a heat sink on the opposite side of said barrier.

2. A heat exchanging element as claimed in claim 1 wherein said heat exchanging element has a shape selected from the group consisting of: i. flatii. circular, and,iii. curved.

3. A heat exchanging element as claimed in claim 1 wherein said heat exchanging element is assembled with heat-transfer plates using spacers between said heat-transfer plates that are secured by a mechanical fixture.

4. A heat exchanging element as claimed in claim 1 wherein said heat exchanging element is assembled with heat-transfer plates using spacers between said heat-transfer plates that are secured by glue.

5. A heat exchanging element in as claimed in claim 1 wherein said heat exchanging element is assembled by inserting said heat-transfer plates into slots of a permanent substrate.

6. A heat exchanging element, said heat exchanging element comprising a plurality of spaced-apart heat transfer plates wherein said plates are assembled in a manner that heat is transferred from a first end of said plates in contact with a heat source on one side of a barrier that separates hot and cold zones, directly to a second end of said plates that are in contact with a heat sink on the opposite side of said barrier and said heat-transfer plates being selected from a group of plates consisting of i. single-phase platesii. composite platesiii. laminated plates, and,iv. surface coated plates.

7. A heat-transfer plate as claimed in claim 6 wherein said single phase plate is made with a material selected from a group of materials consisting of i. metals,ii. metal alloys,iii. ceramics,iv. carbonaceous materials, and,v. polymeric materials.

8. A heat-transfer plate as claimed in claim 7 wherein said metal is selected from a group of metals consisting of i. aluminum,ii. copper,iii. steel, and,iv. titanium.

9. A heat-transfer plate as claimed in claim 7 wherein said metal alloy is selected from a group of metals consisting of i. aluminum,ii. copper,iii. steel, and,iv. titanium.

10. A heat-transfer plate as claimed in claim 7 wherein said ceramic material is selected from a group consisting of i. boron nitrideii. aluminum oxideiii. zinc oxideiv. silicon oxidev. aluminum nitride, and,vi. silicon carbide

11. A heat-transfer plate as claimed in claim 7 wherein said carbonaceous material is selected from a group consisting of i. graphite,ii. exfoliated graphite,iii. graphene,iv. graphene nanoplatelets,v. carbon nanotube, and,vi. carbon fiber.

12. A heat-transfer plate as claimed in claim 7 wherein said composite plate is made with a material selected from a group of materials consisting of i. metal-matrix composite with at least one conductive filler,ii. ceramic-matrix composite with at least one conductive filleriii. polymeric-matrix composite with at least one conductive filler, and,iv. carbonaceous-matrix composite with at least one conductive filler.

13. A heat-transfer plate as claimed as claimed in claim 12 wherein said metal matrix is selected from a group of metals consisting of i. aluminum,ii. copper,iii. steel, and,iv. titanium.

14. A heat-transfer plate as claimed in claim 12 wherein said ceramic matrix is selected from a group of materials consisting of i. aluminum oxide,ii. silicon oxide,iii. zirconium oxide,iv. magnesium oxide,v. yttrium oxide,vi. silicon carbide,vii. silicon nitride,viii. titanium carbide, and,ix. titanium nitride.

15. A heat-transfer plate as claimed in claim 12 wherein said polymeric matrix is selected from a group of materials consisting of i. Polyolefin,ii. polyamide,iii. polyimide,iv. nylon,v. polyester,vi. polystyrene,vii. polyacrylate,viii. polyvinylchloride,ix. fluoropolymers,x. polyvinyl acetate,xi. polybutadienes,xii. polychloroprene,xiii. polyurethanes, and, xiv. copolymers of i. to xiii.

16. A heat-transfer plate as claimed in claim 12 wherein said carbonaceous matrix is selected from a group of materials consisting of i. graphite,ii. exfoliated graphite,iii. graphene,iv. graphene nanoplatelets,v. carbon nanotube,vi. carbon fiber,vii. amorphous carbon, and,viii. diamond.

17. A heat-transfer plate as claimed in claim 12 wherein said conductive filler is selected from a group of materials consisting of i. Graphite,ii. exfoliated graphite,iii. Graphene,iv. graphene nanoplatelet,v. carbon nanotube,vi. Carbon fiber,vii. Diamond,viii. boron nitride,ix. zinc oxide, and,x. metallic powders selected from the group consisting of: filaments, flakes, and, nanotubes.

18. A heat-transfer plate as claimed in claim 6 wherein said laminated plate is made from a substrate laminated on at least one side with carbon-based sheet selected from the group consisting of i. graphene nanoplatelet sheet,ii. graphite sheet,iii. exfoliated graphite sheet,iv. carbon nanotube sheet, and,v. carbon fiber sheet.

19. A heat-transfer plate as claimed in claim 18 wherein said substrate is made with a material elected from the group consisting of i. metals,ii. metal alloys,iii. ceramics,iv. carbonaceous materials, and,v. polymeric materials.

20. A heat-transfer plate as claimed in claim 19 wherein said metal is selected from a group consisting of: i. aluminum,ii. copper,iii. stool, and,iv. titanium.

21. A heat-transfer plate as claimed in claim 19 wherein said metal alloy is selected from a group of metals consisting of: i. aluminum,ii. copper,iii. steel, and,iv. titanium.

22. A heat-transfer plate as claimed in claim 19 wherein said ceramic material is selected from a group consisting of i. aluminum oxide,ii. silicon oxide,iii. zirconium oxide,iv. magnesium oxide,v. yttrium oxide,vi. silicon carbide,vii. silicon nitride,viii. titanium carbide, and,ix. titanium nitride.

23. A heat-transfer plate in claim 19 wherein said carbonaceous material is selected from a group consisting of i. graphite,ii. exfoliated graphite,iii. graphene,iv. graphene nanoplatelets,v. carbon nanotube, and,vi. carbon fiber.

24. A heat-transfer plate as claimed in claim 19 wherein said polymeric matrix is selected from a group of materials consisting of i. polyolefin,ii. polyamide,iii. polyimide,iv. nylon,v. polyester,vi. polystyrene,vii. polyacrylate,viii. polyvinylchloride,ix. fluoropolymers,x. polyvinyl acetate,xi. polybutadienes,xii. polychloroprene,xiii. polyurethanes, and,xiv. copolymers of i. to xiii.

25. A heat-transfer plate as claimed in claim 19 wherein said laminated plate is made by a method selected from the group consisting of i. lamination,ii. coating,iii. extrusion,iv. pressing, and, rolling.

26. A heat-transfer plate as claimed in claim 19 wherein said laminated plate is made by a method selected from the group consisting of i. lamination,ii. coating,iii. extrusion,iv. pressing, and, rolling wherein an adhesive is used.

27. A heat-transfer plate as claimed in claim 6 wherein said surface coated plate is made by coating a substrate on at least one side with a thermally conductive layer comprised of one or more materials selected from the group consisting of i. graphene nano platelets,ii. exfoliated graphite,iii. Graphite,iv. carbon nanotube,v. carbon fiber,vi. boron nitride,vii. alumina, and,viii. diamond.

28. A heat-transfer plate in claim 27 wherein said substrate is made with a material elected from the group consisting of i. metals,ii. metal alloys,iii. ceramics,iv. carbonaceous materials, and,v. polymeric materials.

29. A heat-transfer plate as claimed in claim 28 wherein said metal is selected from a group consisting of i. Aluminum,ii. Copper,iii. Steel, and,iv. Titanium.

30. A heat-transfer plate as claimed in claim 28 wherein said metal alloy is selected from a group of metals consisting of i. aluminum,ii. copper,iii. steel, and,iv. titanium.

31. A heat-transfer plate as claimed in claim 28 wherein said ceramic material is selected from a group consisting of i. aluminum oxide,ii. Silicon oxide,iii. zirconium oxide,iv. magnesium oxide,v. yttrium oxide,vi. silicon carbide,vii. silicon nitride,viii. titanium carbide, and,ix. titanium nitride.

32. A heat-transfer plate as claimed in claim 28 wherein said carbonaceous material is selected from a group consisting of i. Graphite,ii. exfoliated graphite,iii. graphene,iv. graphene nanoplatelets,v. carbon nanotube, and,vi. carbon fiber.

33. A heat-transfer plate as claimed in claim 28 wherein said polymeric matrix is selected from a group of materials consisting of i. Polyolefin,ii. polyamide,iii. polyimide,iv. Nylon,v. polyester,vi. polystyrene,vii. polyacrylate,viii. polyvinylchloride,ix. fluoropolymers,x. polyvinyl acetates,xi. polybutadienes,xii. polychloroprene,xiii. polyurethanes,xiv. copolymers of i. to xiii.

34. A heat-transfer plate as claimed in claim 27 wherein said surface coated plate is made by coating a substrate on at least one side with a thermally conductive layer by a method selected from a group consisting of i. spray coating,ii. screen printing,iii. slot-die coating,iv. blade coating,v. ink-jet printing,vi. gravure coating,vii. chemical vapor deposition,viii. physical vapor deposition, and,ix. electrochemical plating.

35. A heat-transfer plate as claimed in claim 6 wherein said heat-transfer plate has a geometric shape selected from a group consisting of i. flat, ii. corrugated, iii. patterned, and, combinations thereof.

36. A heat-transfer plate as claimed in claim 6 wherein said heat-transfer plate is flexible.

37. A heat-transfer plate as claimed in claim 6 wherein said heat-transfer plate is rigid.

38. A heat-transfer plate as claimed in claim 6 wherein thermal conductivity of said heat-transfer plate is isotropic.

39. A heat-transfer plate as claimed in claim 6 wherein thermal conductivity of said heat-transfer plate is anisotropic.

40. A heat-transfer plate as claimed in claim 6 wherein said heat-transfer plate has an in-plane thermal conductivity that is two orders of magnitude of thru-plane thermal conductivity.

41. A heat-exchanging unit, said heat-exchange unit comprising one or more heat exchanging elements as claimed in claim 1.

42. A heat-exchanging unit as claimed in claim 41 wherein said heat exchanging element is oriented parallel to the flow of heating or cooling media.

43. A heat-exchanging unit as claimed in claim 41 wherein said heat exchanging element is oriented perpendicular to the flow of heating or cooling media.

44. A heat-exchanging unit as claimed in claim 41 wherein said heat exchanging element is oriented at an angle to the flow of heating or cooling media.

45. A heat-exchanging unit in claim 41 wherein said heat exchanging element is oriented at an angle to the flow of heating or cooling fluid or gas to regulate flow pattern and maximize heat exchange between heating and cooling media

46. A heat-exchanging unit in claim 34 wherein said heat exchanging element is housed in a case made with a material selected from i. Metal,ii. Plastic,iii. Composite,iv. Ceramic,v. Laminate.

47. A heat-exchanging unit in claim 34 wherein said heat exchanging element is directly used without a housing.

48. A heat-exchanging unit in claim 34 wherein said heat exchanging unit is tubular or rectangular.

49. A heat exchanger, said heat exchanger is assembled by stacking or otherwise assembled in series with the heat-exchanging unit in claim 34.

50. A heat exchanger, said heat exchanger is configured for heat exchange between liquid-liquid, liquid-gas, gas-gas, liquid-solid, gas-solid, and solid-solid medias.

51. A heat exchanger of claim 1 where in the thermal conductivity is 10 times greater in the direction of the plane than through the plane of the heat transfer plate.

52. A heat exchanger of claim 1 where in the thermal conductivity is 100 times greater in the direction of the plane than through the plane of the heat transfer plate.

53. A heat exchanger of claim 43 where the temperature gradient across the heat transfer plate is less than 25° C.

54. A heat exchanger of claim 43 where the temperature gradient across the heat transfer plate is less than 10° C.