US20090100854A1

US20090100854A1 - Evaporatively cooled condenser

Info

Publication number: US20090100854A1
Application number: US11/975,199
Authority: US
Inventors: Ilya Reyzin; Mohinder Singh Bhatti; Peter E. Fogle
Original assignee: Delphi Technologies Inc
Current assignee: Delphi Technologies Inc
Priority date: 2007-10-18
Filing date: 2007-10-18
Publication date: 2009-04-23

Abstract

An evaporative cooler assembly including a cooler housing in fluid communication with a condenser. A stream of air flows through the cooler housing where it is cooled and across the condenser to dissipate heat from the condenser. The cooler housing includes a plurality of alternating dry and wet channels with a plurality of plates extending between opposite ends of the cooler housing separating the channels. The plates include a plurality of apertures for proportionally increasing from one end to the other the amount of the stream of air flowing from the dry channels through the wet channels and to the condenser.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
An evaporative cooler assembly for pre-cooling a stream of air for a condenser.
2. Description of the Prior Art
Evaporative coolers have been used to pre-cool air, and thus improve the efficiency of heat exchangers. These evaporative coolers typically evaporate a liquid into a stream of air and direct the saturated stream of air across the heat exchanger to dissipate heat from the condenser to the stream of air.
Co-pending Delphi patent application docket number DP-316252 by Wolfe, et al. for an “Evaporatively Pre-Cooled Seat Assembly” discloses an evaporative cooler having a cooler housing including an open air inlet side and a side wall defining opposite ends of the cooler housing. The cooler housing defines a plurality of alternating dry and wet channels, and the cooler housing also includes a plurality of plates extending between the opposite ends for separating the dry and wet channels and providing fluid communication therebetween. The plurality of plates provides a uniform volume of air flowing from the dry channels through the wet channels and to a condenser.

SUMMARY OF THE INVENTION AND ADVANTAGES

The subject invention relates to such an evaporative cooler assembly having a cooler housing in fluid communication with a condenser. The cooler housing defines opposite ends and alternating dry and wet channels. A plurality of plates extends between the opposite ends of the cooler housing to separate the dry and wet channels for proportionally increasing from one end of the cooler housing to the other the volume of a stream of air flowing from the dry channels through the wet channels and to the condenser.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages of the present invention will be readily appreciated, as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 is a fragmentary and perspective view of the evaporatively cooled condenser assembly including a first embodiment of the condenser, a second embodiment of the liquid source and the evaporative cooler;

FIG. 2 is a front elevational view of a plate;

FIG. 3 is a fragmentary and perspective view of the evaporatively cooled condenser including a third embodiment of the condenser, a first embodiment of the liquid source and the evaporative cooler; and

FIG. 4 is a perspective view of a fourth embodiment of the condenser.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the Figures, wherein like numerals indicate corresponding parts throughout the several views, an evaporatively cooled condenser assembly 20 is generally shown including a condenser 22 and an evaporative cooler 24 is shown. The evaporative cooler 24, which is generally indicated, is in fluid communication with the condenser 22, which is also generally indicated. The evaporative cooler 24 provides the condenser 22 with a pre-cooled stream of air. Although the embodiments shown disclose the evaporative cooler 24 in fluid communication with a condenser 22, any heat exchanger may be employed.
A coolant is disposed within the condenser 22, and the condenser 22 has a coolant inlet 26 and a coolant outlet 28 and at least one coolant passage 30 extending therebetween. The at least one coolant passage 30 defines an air gap for allowing a stream of air to flow through the condenser 22. A plurality of air fins 32 is disposed about the coolant passage 30 and in the air gap for transferring heat from the coolant passage 30 to the stream of air.
The coolant enters the coolant inlet 26 of the condenser 22 as a superheated gas and the stream of air cools the coolant to its saturation temperature. The region in which the coolant is cooled from a superheated gas to its saturation temperature is hereinafter referred to as the desuperheat region of the condenser 22. Upon reaching its saturation temperature in the condenser 22, the coolant condenses from the gas phase to a liquid phase while remaining at its saturation temperature. This region where the coolant condenses from a gas to a liquid is hereinafter referred to as the condensation region of the condenser 22. Finally, the liquid coolant undergoes further cooling below its saturation temperature. This region is hereinafter referred to as the subcooling region of the condenser 22. The coolant leaves the condenser 22 through the coolant outlet 28 as a subcooled liquid.
A first embodiment of the condenser 22 is generally indicated in FIG. 1. The condenser 22 includes an upper header 34 extending from the coolant inlet 26 to the coolant outlet 28. A lower header 36 extends parallel to and is vertically spaced from the upper header 34. The at least one coolant passage 30 is further defined by a plurality of tubes 38 having a stadium shaped cross section defining spaced flat sides and round ends. The tubes 38 extend in parallel relationship with each other between the upper and lower headers 34, 36 and establish fluid communication between the upper and lower headers 34, 36. The plurality of air fins 32 is disposed between and brazed to the parallel flat sides of the tubes 38 and extends between the upper and lower headers 34, 36. A first flow separator 40 and a second flow separator 42 are disposed in the upper header 34, and a third flow separator 44 is disposed in the lower header 36. The first flow separator 40 directs the coolant from the upper header 34 to the tubes 38 leading to the lower header 36 and the third flow separator 44 directs the fluid from the lower header 36 to the tubes 38 leading back to the upper header 34. The second flow separator 42 then directs the fluid back to the lower header 36 and then into the coolant outlet 28.
A second embodiment of the condenser 22 is generally indicated in FIG. 4. This embodiment is similar to the first embodiment of the condenser 22 except the plurality of air fins 32 has an incrementally decreasing fin density from the coolant inlet 26 to said coolant outlet 28. The incrementally decreasing fin density provides for the highest rate of cooling in the desuperheat region, which is near the coolant inlet 26 of the condenser 22, and the lowest rate of cooling in the subcooling region, which is near the coolant outlet 28 of the condenser 22.
A third embodiment of the condenser 22 is generally indicated in FIG. 3. The at least one coolant passage 30 is further defined by a tube 38 having a stadium shaped cross-section defining flat sides and round ends. The tube 38 extends through a plurality of U-shapes to form a serpentine pattern from the coolant inlet 26 to the coolant outlet 28. The plurality of U-shapes defines a plurality of tube legs 46 extending in parallel relationship and spaced from one another, and the plurality of air fins 32 is disposed between the tube legs 46 for transferring heat from the tube 38 to the stream of air.
The evaporative cooler 24 has a cooler housing 48 in fluid communication with the condenser 22 for pre-cooling the stream of air. The cooler housing 48 includes a front wall 50 and a side wall 52 in an L-shape having a long leg and a short leg. The cooler housing 48 defines an open air inlet side 54 opposite to the short leg of the L-shape and an open air outlet side 56 opposite to the long leg of the L-shape. A plurality of spaced and parallel plates 58 extending horizontally and transversely to the walls 50, 52 is disposed in the cooler housing 48. The cooler housing 48 is closed over the air outlet side 56 between alternate pairs of plates 58 to define dry channels 60, and the cooler housing 48 is closed over the air inlet side 54 adjacent of the alternate pairs of the plates 58 to define wet channels 62.
Each of the wet channels 62 includes a plurality of spaced wicking partitions 64 extending vertically between the alternate pairs of the plates 58 for separating the wet channels 62 into a plurality of chambers 66 and each of the chambers 66 is lined with a wicking material for retaining a liquid.
A liquid source 68 including a plurality of water inlets 70 is disposed on the cooler housing 48 for supplying the liquid to the chambers 66 of the wet channels 62. A first embodiment of the liquid source 68, generally indicated in FIG. 3, shows the plurality of water inlets 70 extending from a first water inlet 70 disposed near to the air inlet side 54 of the cooler housing 48 to a last water inlet 70 disposed near the side wall 52 of the cooler housing 48. Each of the water inlets 70 has a different water inlet cross-sectional area for controlling the amount of water conveyed into each of the chambers 66 of the wet channels 62 of the evaporative cooler 24. The water inlet cross-sectional area of each of the plurality of water inlets 70 incrementally increases from the first water inlet 70 to the last water inlet 70 for providing the largest volume of water to the chambers 66 near the desuperheat region of the condenser 22 and the smallest volume of water to the chambers 66 near the subcooling region of the condenser 22.
A second embodiment of the liquid source 68 is generally indicated in FIG. 1. In the second embodiment, each of the water inlets 70 has the same cross-sectional area. However, the water inlets 70 may have any cross-sectional area and do not have to either be incrementally increasing or all the same as shown in FIGS. 1 and 3.
Every other plate 58 in the cooler housing 48 includes a plurality of apertures 72 having circular cross sections. The apertures 72 are spaced from each other and extend from a first aperture 72 disposed near desuperheat region of the condenser 22 to a last aperture 72 disposed near the subcooling region of the condenser 22. The plurality of apertures 72 conveys air out of each of the respective dry channels 60 and into at least one of the chambers 66 of the wet channels 62 where the air evaporates the liquid from the wicking material and is then directed out the air outlet side 56 of the cooler housing 48 to the condenser 22.
A first embodiment of the plates 58 is generally shown in FIG. 2. Each of the apertures 72 of the plates 58 corresponds with a single chamber 66 of the wet channels 62, and each of the apertures 72 defines a different cross-sectional area for controlling the amount of air conveyed into each of the chambers 66 of the wet channels 62. The cross-sectional area of each of the plurality of apertures 72 incrementally increases from the first aperture 72 disposed near the desuperheat region of the condenser 22 to the last aperture 72 disposed near the subcooling region of the condenser 22 for providing a proportionally increasing amount of air exiting successive chambers 66 of the wet channels 62. The incrementally increasing cross-sectional areas of the apertures 72 directs the greatest volume of air to the desuperheat region of the condenser 22 and the smallest volume of air to the subcooling region of the condenser 22. Other means may also be employed to direct the greatest volume of air to the desuperheat region of the condenser 22. For example, the plates 58 may also have a plurality of apertures 72, all having the same cross-sectional area, but with a high concentration of apertures 72 on the end of the plates 58 near the desuperheat region of the condenser 22 and a low concentration of apertures 72 on the end of the plates 58 near the subcooling region of the condenser 22.
While the invention has been described with reference to an exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.

Claims

1. An evaporatively cooled condenser assembly for pre-cooling air for a condenser including;

a cooler housing having an open air inlet side and a side wall defining opposite ends of said cooler housing and said cooler housing defining alternating dry channels and wet channels,

a plurality of plates extending between said opposite ends to separate said dry and wet channels for proportionally increasing from one end to the other the amount of a stream of air flowing from said dry channels through said wet channels.

2. An assembly as set forth in claim 1 wherein said plurality of plates includes a plurality of apertures for providing a proportionally greater flow of air to one side of said wet channels and a proportionally lesser flow of air to the other side of said wet channels.

3. An assembly as set forth in claim 2 wherein each of said plurality of apertures defines a different cross-sectional area for controlling the amount of air conveyed into each side of said wet channels.

4. An assembly as set forth in claim 3 wherein said plurality of apertures extends from a first aperture disposed near said open air intake side of said cooler housing to a last aperture disposed near said side wall of said cooler housing, and

said cross-sectional area of each of said plurality of apertures incrementally increases from said first aperture to said last aperture.

5. An assembly as set forth in claim 2 further including a plurality of spaced wicking partitions extending vertically between alternate pairs of said plurality of plates for dividing said wet channels into a plurality of chambers.

6. An assembly as set forth in claim 5 wherein each of said plurality of apertures of said plurality of plates corresponds with a single chamber.

7. An assembly as set forth in claim 5 wherein each of said plurality of chambers is lined with a wicking material for retaining a liquid.

8. An assembly as set forth in claim 5 further including a liquid source having a plurality of water inlets disposed on said cooler housing for supplying the liquid to said chambers of said wet channels.

9. An assembly as set forth in claim 8 wherein said plurality of water inlets of

said liquid source extends from a first water inlet disposed near said air inlet side of said evaporative cooler to a last water inlet disposed near said side wall of said evaporative cooler,

each of said water inlets defines a different water inlet cross-sectional area for controlling the amount of water conveyed into each of said chambers of said wet channels of said evaporative cooler, and

said water inlet cross-sectional area of each of said plurality of water inlets incrementally increases from said first water inlet to said last water inlet for providing an incrementally increasing volume of water to said chambers of said evaporative cooler near said open air intake side of said cooler housing to said chambers disposed near said side wall of said cooler housing.

10. An assembly as set forth in claim 1 wherein said cooler housing further includes a front wall disposed in an L-shape having a long leg and a short leg with said side wall defining said open air inlet side opposite to the short leg of the L-shape and defining an open air outlet side opposite to the long leg of the L-shape.

11. An assembly as set forth in claim 10 wherein said plurality of plates are vertically spaced from each other and extend horizontally and transversely to said walls.

12. An assembly as set forth in claim 11 wherein said cooler housing is closed over said air outlet side between alternate pairs of plates to further define said dry channels.

13. An assembly as set forth in claim 12 wherein said cooler housing is closed over said air inlet side adjacent of said alternate pairs of plates to further define said wet channels.

14. An assembly as set forth in claim 1 further including a condenser in fluid communication with said evaporative pre-cooler assembly and having a coolant inlet and a coolant outlet and at least one coolant passage extending therebetween and defining an air gap for allowing a stream of air to flow through said condenser.

15. An assembly as set forth in claim 14 further including a plurality of air fins disposed about said coolant passage and in said air gap for transferring heat from said coolant passage to the stream of air.

16. An assembly as set forth in claim 15 wherein said condenser further includes an upper header extending from said coolant inlet to said coolant outlet and a lower header extending parallel to and vertically spaced from said upper header.

17. An assembly as set forth in claim 16 wherein said at least one coolant passage is further defined by a plurality of tubes having a cross section defining spaced flat sides and round ends and extending in parallel relationship with each other between said upper and lower headers for establishing fluid communication between said upper and lower headers.

said upper header including a first flow separator and a second flow separator and said lower header including a third flow separator.

18. An assembly as set forth in claim 17 wherein said plurality of air fins is disposed between and brazed to said parallel flat sides of said tubes and extends between said upper and lower headers.

19. An assembly as set forth in claim 18 wherein said upper header includes a first flow separator and a second flow separator and said lower header includes a third flow separator.

20. An assembly as set forth in claim 19 wherein said condenser is further defined by said plurality of air fins having an incrementally decreasing fin density from said coolant inlet to said coolant outlet for providing increased cooling to the condenser near said coolant inlet relative to said coolant outlet.

21. An evaporatively cooled condenser assembly comprising;

a condenser having a coolant inlet and a coolant outlet and at least one coolant passage extending therebetween and defining an air gap for allowing a stream of air to flow through said condenser,

a plurality of air fins disposed about said coolant passage and in said air gap for transferring heat from said coolant passage to the stream of air,

an evaporative cooler having a cooler housing in fluid communication with said condenser for pre-cooling the stream of air,

said cooler housing including a front wall and a side wall in an L-shape having a long leg and a short leg defining an open air inlet side opposite to the short leg of the L-shape and an open air outlet side opposite to the long leg of the L-shape,

a plurality of vertically spaced and parallel plates extending horizontally and transversely to said walls from said open air inlet side to said side wall,

said cooler housing being closed over said air outlet side between alternate pairs of said plates and defining dry channels,

said cooler housing being closed over said air inlet side adjacent of said alternate pairs of said plates and defining wet channels,

each of said wet channels including a plurality of spaced wicking partitions extending vertically between said alternate pairs of said plates for separating said wet channels into a plurality of chambers,

each of said chambers being lined with a wicking material for retaining a liquid,

a liquid source including a plurality of water inlets disposed on said cooler housing for supplying the liquid to said chambers of said wet channels,

alternate of said plates including a plurality of apertures having a cross section being circular in shape being spaced and extending from a first aperture disposed near said coolant inlet of said condenser to a last aperture disposed near said coolant outlet of said condenser for conveying air out of each of said respective dry channels and into at least one of said chambers of said wet channels to evaporate liquid from said wicking material,

a single aperture corresponding with each of said chambers of said wet channels,

each of said plurality of apertures in said plates defining a different cross-sectional area for controlling the amount of air conveyed into each of said chambers of said wet channels, and

said cross-sectional area of each of said plurality of apertures incrementally increasing from said first aperture to said last aperture for providing a proportionally increasing amount of air flowing through successive chambers of said wet channels.

22. An assembly as set forth in claim 21 wherein said condenser further includes:

an upper header extending from said coolant inlet to said coolant outlet and a lower header extending parallel to and vertically spaced from said upper header,

said at least one coolant passage is further defined by a plurality of tubes having a cross section defining spaced flat sides and round ends and extending in parallel relationship with each other between said upper and lower headers for establishing fluid communication between said upper and lower headers,

said plurality of air fins disposed between and brazed to said parallel flat sides of said tubes and extending between said upper and lower headers,

23. An assembly as set forth in claim 22 wherein said condenser is further defined by said plurality of air fins having an incrementally decreasing fin density from said coolant inlet to said coolant outlet for providing increased cooling to said condenser near said coolant inlet relative to said coolant outlet.

24. An assembly as set forth in claim 21 wherein said coolant passage is further defined by a tube having a cross section defining flat sides and rounded ends and extending through a plurality of U-shapes to form a serpentine pattern from said coolant inlet to said coolant outlet,

said plurality of U-shapes defines a plurality of tube legs in parallel relationship with one another, and

said plurality of air fins is disposed between said tube legs of said tube for transferring heat from said tube to the passing air.

25. An assembly as set forth in claim 21 wherein said plurality of water inlets of said liquid source extends from a first water inlet being disposed adjacent to said air inlet side of said evaporative cooler to a last water inlet being disposed adjacent to said side wall of said evaporative cooler,

each of said water inlets having a different water inlet cross-sectional area for controlling the amount of water conveyed into each of said chambers of said wet channels of said evaporative cooler,

said water inlet cross-sectional area of each of said plurality of water inlets incrementally increasing from said first water inlet to said last water inlet for providing an incrementally increasing volume of water from said chambers of said evaporative cooler near said coolant outlet of said condenser to said plurality of chambers near said coolant inlet of said condenser.