CORE ASSEMBLY FOR A HEAT EXCHANGER AND METHOD OF ASSEMBLING

Abstract

A core assembly for a heat exchanger includes a plurality of parting sheets defining a plurality of fluid passages including a plurality of first fluid passages and a plurality of second fluid passages arranged in an alternating arrangement, wherein each of the plurality of parting sheets comprises a thickness of about 0.016″. Also included is a plurality of first fluid passage fins disposed between the plurality of parting sheets within each of the plurality of first fluid passages. Further included is a plurality of second fluid passage fins disposed between the plurality of parting sheets within each of the plurality of second fluid passages. Yet further included is a plurality of closure bars disposed between respective pairs of the plurality of parting sheets.

Description

BACKGROUND OF THE INVENTION

The present invention relates to heat exchanger arrangements, and more particularly to a core assembly for a heat exchanger.

A heat exchanger is utilized to cool or heat a fluid medium by flowing two fluid mediums adjacent to each other through a core assembly. The heat exchanger may be employed in various applications and subjected to specific thermal requirements. The dimensions of the components of the heat exchanger, and more particularly the core assembly play a significant role in meeting the operating requirements and in withstanding the thermal requirements noted above.

BRIEF DESCRIPTION OF THE INVENTION

According to one embodiment, a core assembly for a heat exchanger includes a plurality of parting sheets defining a plurality of fluid passages including a plurality of first fluid passages and a plurality of second fluid passages arranged in an alternating arrangement, wherein each of the plurality of parting sheets comprises a thickness of about 0.016″ (about 0.406 mm) Also included is a plurality of first fluid passage fins disposed between the plurality of parting sheets within each of the plurality of first fluid passages. Further included is a plurality of second fluid passage fins disposed between the plurality of parting sheets within each of the plurality of second fluid passages. Yet further included is a plurality of closure bars disposed between respective pairs of the plurality of parting sheets.

According to another embodiment, a method of assembling a heat exchanger is provided. The method includes stacking a plurality of first fins having a fin height of about 0.088″ (about 2.24 mm), a plurality of second fins having a fin height of about 0.324″ (about 8.23 mm), at least one closure bar within a plurality of parting sheets. The method also includes applying a brazing material to the plurality of parting sheets. The method further includes heating the core assembly to activate the brazing material and adhere the plurality of fins, the at least one closure bar and the plurality of parting sheets to each other.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a front perspective view of a heat exchanger;

FIG. 2 is front elevational view of the heat exchanger;

FIG. 3 is a top elevational view of the heat exchanger;

FIG. 4 is a schematic illustration of a core assembly of the heat exchanger;

FIG. 5 is a schematic illustration of a first fluid passage of the core assembly; and

FIG. 6 is a schematic illustration of a second fluid passage of the core assembly.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1-3, a heat exchanger 10 is illustrated. The heat exchanger 10 may be used in conjunction with an assembly or system of a vehicle, such as an aircraft, however, it is contemplated that other vehicles may benefit from the embodiments described herein. In one embodiment, the heat exchanger 10 is part of an air conditioning system or refrigeration system of an aircraft. In particular, a galley cooling refrigeration unit may employ the heat exchanger 10 for cooling purposes.

The heat exchanger 10 includes a core assembly 12 disposed within a housing 14. The core assembly 12 is formed of a width W, a length L, and a height H. In one embodiment, the core assembly 12 is formed of volumetric dimensions of about 4.0″×14.4″×10.1″ (about 10.2 mm×36.6 mm×25.7 mm) The housing 14 includes a first fluid inlet 16 for a first fluid 18, such as a liquid. The first fluid 18 exits through a first fluid outlet 20. Additionally, the housing 14 is configured to allow a second fluid 21, such as ram air, to pass through the core assembly 12 in a cross-flow manner, with respect to the first fluid 18. The core assembly 12 defines a plurality of first fluid passages 22 and a plurality of second fluid passages 24 for the first and second fluids 18, 21. In one embodiment, the number of the plurality of first fluid passages 22 is twenty-two (22), while the number of the plurality of second fluid passages 24 is twenty-three (23).

Referring to FIGS. 4-6, each of the plurality of first and second fluid passages 22, 24 are interspersed within the core assembly 12 to provide for thermal communication and transfer between the first and second fluids 18, 21. Each of the plurality of first and second fluid passages 22, 24 are defined by parting sheets 26 on two sides and by closure bars 28 on two sides. In one embodiment, the parting sheets 26 have a thickness of about 0.016″ (about 0.406 mm) The closure bars 28 provide a desired support structure for the core assembly 12.

A plurality of first fins 30 is disposed within the plurality of first fluid passages 22 between corresponding pairs of the parting sheets 26. Similarly, a plurality of second fins 32 is disposed within the plurality of second fluid passages 24 between corresponding pairs of the parting sheets 26. The fins 30, 32 are shaped to have alternating peaks that extend between corresponding parting sheets. In one embodiment, the fins 30, 32 are formed in a “ruffled” geometry along a continuous sheet within each of the plurality of fluid passages 22, 24. Although the contemplated dimensions of the fins 30, 32 may vary, in one embodiment, each of the plurality of first fluid passage fins 30 comprises a fin height of about 0.088″ (about 2.24 mm) and a fin thickness of about 0.004″ (about 0.102 mm) The continuous sheet of each of the plurality of first fluid passage fins 30 comprises a fin density of about 30 fins per inch. In one embodiment, each of the plurality of second fluid passage fins 32 comprises a fin height of about 0.324″ (about 8.23 mm) and a fin thickness of about 0.003″ (about 0.076 mm) The continuous sheet of each of the plurality of second fluid passage fins comprises a fin density of about 26.5 fins per inch.

Each of the plurality of second fluid passages 24 include a guard fin 34 proximate a leading edge 36 and a trailing edge 38 of the direction of fluid flow. The guard fin 34 protects the plurality of second fins 32 against handling damage during processing, installation and aggressive cleaning and to protect against foreign object damage (FOD) and fin erosion during service. In one embodiment, the guard fin 34 comprises a fin height of about 0.324″ (about 8.23 mm), a fin thickness of about 0.012″ (about 0.305 mm), and a fin length of about 0.250″ (about 6.35 mm)

The core assembly 12 is assembled by stacking the plurality of first fins 30 and the plurality of second fins 32, the closure bars 28 within the parting sheets 26. A brazing material is utilized on the parting sheets 26 to attach each part to adjacent joining parts. Accordingly, the interface between each of the closure bars 28, the parting sheets 26 and the fins 30, 32 fit within each other. Once the parts comprising the core assembly 12 are inter-fit within each other with the brazing material disposed at each interface with the parting sheets 26, the core assembly 12 is heated to activate the brazing material and adhere the several core assembly parts together. The described assembly method for the core assembly 12 is only one such example of a fabrication technique that will benefit from the disclosure and application of this invention.

While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.

Claims

1. A core assembly for a heat exchanger comprising:

a plurality of parting sheets defining a plurality of fluid passages including a plurality of first fluid passages and a plurality of second fluid passages arranged in an alternating arrangement, wherein each of the plurality of parting sheets comprises a thickness of about 0.016″;

a plurality of first fluid passage fins disposed between the plurality of parting sheets within each of the plurality of first fluid passages;

a plurality of second fluid passage fins disposed between the plurality of parting sheets within each of the plurality of second fluid passages; and

a plurality of closure bars disposed between respective pairs of the plurality of parting sheets.

2. The core assembly of claim 1, wherein each of the plurality of first fluid passage fins comprises a continuous sheet including a ruffled fin geometry and a plurality of alternating peaks extending between corresponding parting sheets.

3. The core assembly of claim 2, wherein the continuous sheet of each of the plurality of first fluid passage fins comprises a fin height of about 0.088″ and fin thickness of about 0.004″.

4. The core assembly of claim 2, wherein the continuous sheet of each of the plurality of first fluid passage fins comprises about 30 fins per inch.

5. The core assembly of claim 1, wherein each of the plurality of second fluid passage fins comprises a continuous sheet including a ruffled fin geometry and a plurality of alternating peaks extending between corresponding parting sheets.

6. The core assembly of claim 5, wherein the continuous sheet of each of the plurality of second fluid passage fins comprises a fin height of about 0.324″ and a fin thickness of about 0.003″.

7. The core assembly of claim 5, wherein the continuous sheet of each of the plurality of second fluid passage fins comprises about 26.5 fins per inch.

8. The core assembly of claim 1, further comprising a plurality of guard fins disposed proximate a leading edge and a trailing edge of the plurality of second fluid passage fins.

9. The core assembly of claim 8, wherein each of the plurality of guard fins comprises a fin height of about 0.324″, a fin thickness of about 0.012″, and a fin length of about 0.250″.

10. The core assembly of claim 1, wherein the plurality of first fluid passages comprises a plurality of liquid passages and the plurality of second fluid passages comprises a plurality of ram air passages.

11. The core assembly of claim 10, wherein the plurality of liquid passages comprises about 22 passages and the plurality of ram air passages comprises about 23 passages.

12. The core assembly of claim 1, wherein the heat exchanger is disposed on an aircraft.

13. The core assembly of claim 12, wherein the heat exchanger is in operative association with a galley refrigeration unit.

14. A method of assembling a heat exchanger comprising:

stacking a plurality of first fins having a fin height of about 0.088″, a plurality of second fins having a fin height of about 0.324″, at least one closure bar within a plurality of parting sheets;

applying a brazing material to the plurality of parting sheets; and

heating the core assembly to activate the brazing material and adhere the plurality of fins, the at least one closure bar and the plurality of parting sheets to each other.