HEAT EXCHANGER

Abstract

A heat exchanger (10) that is included in a cabinet (11) housing a plurality of baffles (12, 13). The baffles (12, 13) are arranged alternately and are spaced by a sheet material (14) that provides for the transfer of heat between gases passing through the baffles (12, 13). The baffles (12) each have a plurality of dividing walls (21) that provide a plurality of passages (22). The passages (22) extend between opposite longitudinal sides of the heat exchanger (10). The baffles (13) each have a plurality of dividing walls (33) that provide a plurality of passages (34) that extend between opposite end portions of the heat exchanger (10).

Description

FIELD

The present invention relates to baffles employed in heat exchangers.

BACKGROUND

It is known to form heat exchangers from a stack of baffles with the baffles separated by sheet material. The baffles provide a plurality of passages through which air passes, with heat being exchanged between air passing through adjacent baffles. If so required the transfer of moisture was also provided. Such heat exchangers are described in Australian Patent Application 771202 and 771211. Modifications of these heat exchangers are described in International Patent Applications PCT/AU2004/000103, PCT/AU2005/001097, PCT/AU2008001299, PCT/AU2008/001301 and PCT/AU2008/1001703.

A disadvantage of the above discussed heat exchangers is that heat flows between adjacent baffles if not optimized.

OBJECT

It is the object of the present invention to overcome or substantially ameliorate the above disadvantage.

SUMMARY

There is disclosed herein a heat exchanger including:

a first baffle with a configuration providing first and second longitudinal sides joined by first and second transverse ends, the baffle providing a plurality of passages through which a fluid passes from an inlet to an outlet, the inlet being at said first side and the outlet being at said second side, with the passages extending at least partly longitudinally and transversely relative to said longitudinal sides;

a second baffle, the baffle being of a configuration to co-operate with the first baffle and so as to have a first and a second longitudinal side and, a first and a second transverse end, the second baffle having a plurality of passages through which a fluid passes, the passages of the second baffle extending from the second baffle first transverse end to the second baffle second transverse end; and

a sheet material between the first and second baffles to provide for the transfer of heat between the fluid passing through the passages of the first baffle and the fluid passing through the passages of the second baffle.

Preferably, said configuration is square or rectangular.

Preferably, each of the passages of the first baffle include a first length, a second length and a third length arranged in series, the first length extending from the first side of the first baffle, the second length being generally parallel to the sides of the first baffle, and the third length extending to the second side.

Preferably, the first and third lengths are inclined by approximately 90° to the sides of the first baffle.

Preferably, the second lengths are inclined by approximately 90° to the first and third lengths.

Preferably, the passages of the second baffle are generally parallel to the sides of the second baffle.

Preferably, the baffles are generally planar.

Preferably, the sheet material provides for the transfer of moisture between the fluid passing through the passages of the first baffle and the fluid passing through the passages of the second baffle.

In an alternative preferred form, the sheet material substantially prevents the transfer of moisture between the fluid passing through passages of the first baffle and the fluid passing through the passages of the second baffle.

Preferably, both baffles are of a rectangular configuration so that the longitudinal sides each have a length and the transfer ends each have a length less than the length of the longitudinal sides.

Preferably, the heat exchanger is adapted to provide for the transfer of heat between the fluids, when the fluids are a gas.

Preferably, the heat exchanger is adapted to provide for the transfer of heat between the fluids, where the fluids are air.

BRIEF DESCRIPTION OF DRAWINGS

Preferred forms of the present invention will now be described by way of example with reference to the accompanying drawings wherein:

FIG. 1 is a schematic isometric view of a heat exchanger;

FIG. 2 is a schematic isometric view of baffles and sheet material employed in the heat exchanger of FIG. 1;

FIG. 3 is a schematic plan view of one of the baffles of FIG. 2;

FIG. 4 is a schematic side elevation of the baffle of FIG. 3;

FIG. 5 is a schematic plane view of a further baffle shown in FIG. 2; and

FIG. 6 is a schematic and elevation of the baffle of FIG. 4.

DESCRIPTION OF EMBODIMENTS

In the accompanying drawings there is schematically depicted a heat exchanger 10. The heat exchanger 10 includes a cabinet 11 that houses a plurality of baffles 12 and 13. In this embodiment the baffles 12 and 13 are generally vertically oriented, that is they generally each lie in their respective vertical planes. In an alternative arrangement the baffles may be horizontally oriented.

The baffles 12 and 13 are arranged alternately and are separated by sheet material 14. The sheet material 14 (as best seen in FIG. 2) provides a plurality of slots 15 and 16, with the baffles 12 being located in slots 15 and the baffles 13 being located in slots 16. Preferably, the sheet material 15 consists of a plurality of individual sheets 37, each sheet 37 being located between adjacent baffles 12 and 13.

Preferably, the baffle 12 is of a rectangular or square configuration so as to have a first longitudinal side 17 and a second longitudinal side 18, the sides 17 and 18 being generally parallel and co-extensive. Joining the sides 17 and 18 are transverse ends 19 and 20, the ends 19, 20 being generally parallel and co-extensive, and generally perpendicular to the sides 17 and 18.

The baffle 12 (as best seen in FIGS. 3 and 4) includes a plurality of dividing walls 21 that provide a plurality of passages 22 through which air passes from an inlet 23 to an outlet 24. Each of the passages 22 includes a first passage length 25, a second passage length 26 and third passage length 27, with the lengths 25, 26 and 27 arranged in series extending from the inlet 23 to the outlet 24. Air enters the inlet 23 passes along the passages 22 to exit via the outlet 24.

As is best seen in FIG. 3, the first lengths 25 extend generally perpendicular from the side 27, with the lengths 27 extending generally perpendicular to the side 18. The lengths 26 extend generally parallel to the sides 17 and 18.

The baffles 13 are best seen in FIGS. 5 and 6. Each of the baffles 13 is of the same rectangular configuration as the baffles 12, so as to have a pair of longitudinal sides 28 and 29 joined by transverse ends 30 and 31. The baffle 13 has a plurality of dividing walls 33 that extend generally parallel to the sides 28 and 29 so as to provide a plurality of longitudinal extending passages 34. The passages 34 extend generally parallel to the sides 28 and 29 and extend from an inlet 35 to an outlet 36.

The sheet material 14 provides for the transfer of heat between air passing through the passages 22, and the passages 34.

The above described preferred embodiment has the advantage of increasing the length over which the second lengths 26 are aligned with the passages 34, relative to previously known heat exchangers as described previously. This provides for an increase in the total length of counter current air flow within the heat exchanger 10, thereby increasing the heat transfer between air passing through the passages 22 and air passing through the passages 34. If the sheet material 15 is moisture pervious, then the transfer of moisture is also enhanced.

The above described preferred embodiment has the further advantage of increasing the average temperature difference between air passing through the second lengths 26 and the passages 34.

Claims

1. A heat exchanger including:

a first baffle with a configuration providing first and second longitudinal sides joined by first and second transverse ends, the baffle providing a plurality of passages through which a fluid passes from an inlet to an outlet, the inlet being at said first side and the outlet being at said second side, with the passages extending at least partly longitudinally and transversely relative to said longitudinal sides;

a second baffle, the baffle being of a configuration to co-operate with the first baffle and so as to have a first and a second longitudinal side and, a first and a second transverse end, the second baffle having a plurality of passages through which a fluid passes, the passages of the second baffle extending from the second baffle first transverse end to the second baffle second transverse end; and

a sheet material between the first and second baffles to provide for the transfer of heat between the fluid passing through the passages of the first baffle and the fluid passing through the passages of the second baffle.

2. The heat exchanger of claim 1, wherein said configuration is square or rectangular.

3. The heat exchanger of claim 1, wherein each of the passages of the first baffle include a first length, a second length and a third length arranged in series, the first length extending from the first side of the first baffle, the second length being generally parallel to the sides of the first baffle, and the third length extending to the second side.

4. The heat exchanger of claim 3, wherein the first and third lengths are inclined by approximately 90° to the sides of the first baffle.

5. The heat exchanger of claim 4, wherein the second lengths are inclined by approximately 90° to the first and third lengths.

6. The heat exchanger of claim 1, wherein the passages of the second baffle are generally parallel to the sides of the second baffle.

7. The heat exchanger of claim 1, wherein the baffles are generally planar.

8. The heat exchanger of claim 1, wherein the sheet material provides for the transfer of moisture between the fluid passing through the passages of the first baffle and the fluid passing through the passages of the second baffle.

9. The heat exchanger of claim 1, wherein the sheet material substantially prevents the transfer of moisture between the fluid passing through passages of the first baffle and the fluid passing through the passages of the second baffle.

10. The heat exchanger of claim 1, wherein both baffles are of a rectangular configuration so that the longitudinal sides each have a length and the transfer ends each have a length less than the length of the longitudinal sides.

11. The heat exchanger of claim 1, wherein the heat exchanger is adapted to provide for the transfer of heat between the fluids, when the fluids are a gas.

12. The heat exchanger of claim 1, wherein the heat exchanger is adapted to provide for the transfer of heat between the fluids, where the fluids are air.

13. The heat exchanger of claim 5, wherein the passages of the second baffle are generally parallel to the sides of the second baffle.

14. The heat exchanger of claim 13, wherein the baffles are generally planar.

15. The heat exchanger of claim 14, wherein both baffles are of a rectangular configuration so that the longitudinal sides each have a length and the transfer ends each have a length less than the length of the longitudinal sides.

16. The heat exchanger of claim 1, wherein said configuration is rectangular so that both baffles are of a rectangular configuration so that the longitudinal sides each have a length and the transfer ends each have a length less than the length of the longitudinal sides, each of the passages of the first baffle include a first length, a second length and a third length arranged in series, the first length extending from the first side of the first baffle, the second length being generally parallel to the sides of the first baffle, and the third length extending to the second side, the first and third lengths are inclined by approximately 90° to the sides of the first baffle, the second lengths are inclined by approximately 90° to the first and third lengths, the passages of the second baffle are generally parallel to the sides of the second baffle, and the baffles are generally planar.

17. The heat exchanger of claim 16, wherein the heat exchanger is adapted to provide for the transfer of heat between the fluids, when the fluids are a gas.

18. The heat exchanger of claim 16, wherein the heat exchanger is adapted to provide for the transfer of heat between the fluids, where the fluids are air.

19. The heat exchanger of claim 16, wherein the sheet material provides for the transfer of moisture between the fluid passing through the passages of the first baffle and the fluid passing through the passages of the second baffle.

20. The heat exchanger of claim 16, wherein the sheet material substantially prevents the transfer of moisture between the fluid passing through passages of the first baffle and the fluid passing through the passages of the second baffle.