Heat exchanger and use thereof

• US 20070084593A1
• Filed: 09/30/2004
• Published: 04/19/2007
• Est. Priority Date: 10/02/2003
• Status: Active Grant

• Current Assignee: Hiflux Limited
• Original Assignee: Hiflux Limited
• Inventors: Demargne, Albert, Besant, Tanzi, Pratt, Arnold James, Coplin, John
• Granted Patent: US 8,616,269 B2
• Time in Patent Office: Days
• US Class Current: 165/167
• CPC Class Codes: F28D 9/005 the plates having openings therein for both heat-exchange media
• CPC Class Codes: F28F 3/022 the means being wires or pins

Abstract

A heat exchanger comprises a plurality of plates (7, 9, 11, 13) each having first (15, 19) and second (17, 21) heat transfer surfaces on reverse sides. The plates are arranged in a stack with spacings between mutually facing heat transfer surfaces of adjacent plates. Alternate spacings in the stack providing respectively, a first fluid path (51, 52) for a first fluid and a second fluid path (57, 59) for a second fluid. The plates are arranged in a plurality of groups, each comprising at least two plates. Pin means are provided in the form of a plurality of groups of pins (23). The pins of each pin group are arranged to bridge plates of a respective plate group.

Claims

1. A heat exchanger comprising a plurality of plates each having first and second heat transfer surfaces on reverse sides thereof, said plates being arranged in a stack with spacings between mutually facing heat transfer surfaces of adjacent plates, alternate spacings in the stack providing respectively, a first fluid path for a first fluid and a second fluid path for a second fluid, and wherein the plates are arranged in a plurality of groups, each comprising at least two plates, pin means being provided comprising a plurality of groups of pins, the pins of each pin group being arranged to bridge plates of a respective plate group, wherein the pin means also comprises outer pins extending from the outermost heat transfer surfaces of at least one group of plates, said outer pins terminating in respective pin free ends, and wherein at least some pins extend only from the first heat transfer surface of at least one plate in at least one group and are offset with respect to pins extending only from the second heat transfer surface of that plate, said pins which are offset from each other being brazed or welded to said plate.

2. A heat exchanger according to claim 1, wherein the groups of plates are arranged so that there is a gap between the free ends of the outer pins extending from an outermost heat transfer surface of one group and the free ends of the outer pins extending from an outermost heat transfer surface of an adjacent group.

3. A heat exchanger according to claim 1, wherein pins having mutually facing free ends are substantially in-line.

4. A heat exchanger according to claim 3, when dependent upon claim 3, wherein pins having mutually facing free ends are substantially offset.

5. A heat exchanger according to claim 1, wherein each group of plates consists of an even number of the plates.

6. A heat exchanger according to claim 1, wherein each group of plates consists of two of the plates.

7. A heat exchanger according to claim 1, wherein the first fluid path is connected to a source of first fluid to receive the first fluid therefrom and the second fluid path is connected to a source of second fluid to receive the second fluid therefrom.

8. A heat exchanger according to claim 7, wherein the pressure of the first fluid at its source is from 100% to 2000% of the pressure of the second fluid at its source.

9. A heat exchanger according to claim 1, wherein the pin means comprises pins which are aligned in substantially uniformly spaced rows and the first and second fluids are directed to flow in substantially the same direction or substantially in counter direction in the respective first and second fluid paths.

10. A heat exchanger according to claim 9, wherein the rows are substantially perpendicular to the direction of flow of the first and second fluids.

11. A heat exchanger according to claim 9, wherein the rows are at an angle at from 45 to 85 relative to the direction of flow of the first and second fluids.

12. A heat exchanger according to claim 9-11, wherein the pins in alternate rows are respectively staggered relative to each other.

13. A heat exchanger according to claim 1, wherein the pin means comprises at least some pins which are substantially circular in cross-section.

14. A heat exchanger according to claim 13, wherein the ratio of average distance between pin centers to average pin diameter is from 1.25 to 4.0.

15. A heat exchanger according to claim 1, wherein the pin means comprises at least some pins which are provided with at least one surface feature for enhancing aerodynamic flow and/or heat transfer.

16. A heat exchanger according to claim 1, wherein the ratio of the mean spacing between plates defining the first fluid path in a central region of the exchanger to the mean spacing between plates defining the second fluid path in the same region is from 1:

10 to 100;

1, preferably from 1;

10 to 10;

1.

17. A heat exchanger according to claim 1, wherein the width across the plates in a direction approximately or substantially orthogonal to the direction of flow of at least one of the first and second fluids, progressively narrows in a respective region approaching inflow of the first fluid and/or of the second fluid.

18. A heat exchanger according to claim 1, wherein inflow and/or outflow of one of the first and second fluids is directed through respective tube means passing through the stack of plates and provided with at least one opening into the respective first fluid path and/or second fluid path.

19. A heat exchanger according to claim 18, wherein inflow and/or outflow of said other of the first and second fluids is directed within a respective manifold wall at least partially surrounding the respective tube means.

20. A heat exchanger according to claim 1, wherein the plates are substantially flat.

21. A heat exchanger according to claim 1, wherein the plates are at least partially curved.

22. A heat exchanger according to claim 1, wherein the stack is substantially cubic.

23. A heat exchanger according to claim 1, wherein the plates are arranged radially, preferably in involute form.

28. A power producing apparatus comprising a power producing plant and a heat exchanger according to claim 1.

29. An apparatus according to claim 28, wherein the heat exchanger is arranged to recover heat from exhaust fluids from the power producing plant to heat fluids following compression.

30. An apparatus according to claim 29, arranged such that the exhaust gases exiting the power plant heat air from the plant after compression.

31. An apparatus according to claim 28, wherein the power producing plant comprises a gas turbine.

32. An apparatus according to claim 28, wherein the heat exchanger is applied to a turbo-charger or a super-charger of a reciprocating engine power producer.

33. An apparatus according to claim 28, wherein the heat exchanger is used to cool air before the air enters the reciprocating power producer.

34. An apparatus according to claim 33, wherein the heat exchanger is used to cool air after compression of the air in the turbo-charger or super-charger.

35. An apparatus according to claim 28, wherein the heat exchanger is segmented and the segments are arranged around a shaft of the power plant.

36. An apparatus according to claim 28, wherein the heat exchanger is cylindrical and a shaft of the power plant passes axially through the centre of the cylinder.

37. An apparatus according to claim 28, wherein the power producing plant comprises a fuel cell.

24. A heat exchanger comprising a plurality of stacked pairs of spaced apart plates, the plates in each pair each having a respective mutually facing inner surface defining therebetween, a first fluid path for a first fluid and the plates in each pair each having a respective outer facing surface reverse from said respective inner surface, the outer facing surface of a plate in one pair being spaced apart from and facing an outer facing surface of a plate in an adjacent pair to define therebetween a second fluid path for a second fluid, the plates in a pair being bridged across the first fluid path by a plurality of pins, wherein the pin means also comprises outer pins extending from the outermost heat transfer surfaces of at least one pair of plates, said outer pins terminating in respective pin free ends, and wherein at least some pins extend only from the first heat transfer surface of at least one plate in at least one pair and are offset with respect to pins extending only from the second heat transfer surface of that plate, said pins which are offset from each other being brazed or welded to said plate.

25. A heat exchanger according to claim 24, wherein the pairs of plates are arranged so that there is a gap between the free ends of the outer pins extending from an outermost heat transfer surface of one pair and the free ends of the outer pins extending from an outermost heat transfer surface of an adjacent pair.

26. A heat exchanger according to claim 24, wherein pins having mutually facing free ends are substantially in-line.

27. A heat exchanger according to claim 24, wherein pins having mutually facing free ends are substantially offset.

38. A method for manufacturing a heat exchanger comprising a plurality of plates each having first and second heat transfer surfaces on reverse sides thereof, said plates being arranged in a stack with spacings between mutually facing heat transfer surfaces of adjacent plates, alternate spacings in the stack providing respectively, a first fluid path for a first fluid and a second fluid path for a second fluid and wherein the plates are arranged in a plurality of groups, each comprising at least two plates, pin means being provided comprising a plurality of groups of pins, the pins of each pin group being arranged to bridge plates of a respective plate group, wherein the pin means also comprises outer pins extending from the outermost heat transfer surfaces of at least one group of plates, said outer pins terminating in respective pin free ends, and wherein at least some pins extend only from the first heat transfer surface of at least one plate in at least one group and are offset with respect to pins extending only from the second heat transfer surface of that plate, said pins which are offset from each other being brazed or welded to said plate, the method comprising providing one or more workpieces and forming the plates and pin means integrally from said workpiece or workpieces by welding or brazing said pin means to said plates.