EVAPORATIVE MEDIA PAD WITH REDUCED INTERNAL SPACING

Abstract

Evaporative media pads for direct evaporative cooling systems and, in particular, evaporative media pads that have a reduced internal spacing to increase cooling capacity. In one embodiment, an evaporative media pad includes a plurality of sheets, each of the plurality of sheets including a plurality of flutes, each of the plurality of flutes having a flute height of at most 4.5 mm. In one embodiment, the flute height is at most 4 mm.

Claims

1. An evaporative media pad comprising: a plurality of sheets, each of the plurality of sheets having a width and including a plurality of flutes, each of the plurality of flutes having a same flute height of at most 4.5 mm each of the plurality of flutes having a corresponding one of the plurality of sheets and extending across an entirety of the width of the corresponding one of the plurality of sheets, the evaporative media pad being assembled such that the plurality of flutes of adjacent sheets of the plurality of sheets extend in different directions.

2. The evaporative media pad of claim 1, wherein the flute height is between 3 mm and 4.5 mm.

3. The evaporative media pad of claim 1, wherein the flute height is between 3.5 mm and 4.25 mm.

4. The evaporative media pad of claim 1, wherein the flute height is between 3.75 mm and 4 mm.

5. The evaporative media pad of claim 1, wherein each of the plurality of sheets is composed of cellulose paper.

6. An evaporative cooling system, comprising: an air-water contact body, the air-water contact body including a plurality of sheets, each of the plurality of sheets having a width and a plurality of linear undulations extending across an entirety of the width of the sheet in a single direction, each of the plurality of undulations having a height of at most 4 mm; and a fluid distribution system configured to deliver fluid to the air-water contact body.

7. The evaporative cooling system of claim 6, wherein the height is between 3 mm and 4 mm.

8. The evaporative cooling system of claim 6, wherein the height is between 3.5 mm and 4 mm.

9. The evaporative cooling system of claim 6, wherein the height is between 3.75 mm and 4 mm.

10. The evaporative cooling system of claim 6, wherein each of the linear undulations extends in a direction that is at an angle from horizontal.

11. The evaporative cooling system of claim 7, wherein the air-water contact body is assembled such that alternating sheets of the plurality of sheets include linear undulations extending in a first direction and at a first angle from horizontal and intervening sheets of the plurality of sheets between the alternating sheets of the plurality of sheets include linear undulations extending in a second direction and at a second angle from horizontal.

12. The evaporative cooling system of claim 1, wherein: the first direction and the second direction are different; and the first angle and the second angle are the same.

13. The evaporative cooling system of claim 1, wherein: the first direction and the second direction are different; and the first angle and the second angle are different.

14. The evaporative cooling system of claim 6, wherein the air-water contact body is an evaporative media pad.

15. The evaporative cooling system of claim 14, wherein the evaporative media pad is composed of cellulose paper.

16. The evaporative cooling system of claim 14, wherein the plurality of sheets are assembled such that the plurality of linear undulations of adjacent sheets are in contact with each other.

17. An evaporative media pad for use in a direct evaporative cooling system, the evaporative media pad comprising: a plurality of sheets, each of the plurality of sheets lying in a plane, having a width, and including: a first plurality of flutes extending in a first direction from the plane, each of the first plurality of flutes having a zenith point, the first plurality of flutes extending across an entirety of the width of the sheet; and a second plurality of flutes extending in a second direction from the plane opposite the first direction, each of the second plurality of flutes having a zenith point, the second plurality of flutes extending across an entirety of the width of the sheet, the distance between zenith points of adjacent flutes being at most 4 mm.

18. The evaporative media pad of claim 17, wherein the distance between zenith points of adjacent flutes is at least 3 mm.

19. The evaporative media pad of claim 17, wherein the distance between zenith points of adjacent flutes is at least 3.5 mm.

20. The evaporative media pad of claim 17, wherein the distance between zenith points of adjacent flutes is at least 3.75 mm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] A more complete understanding of the present invention, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:

[0023] FIG. 1 shows a portion of an exemplary direct evaporative cooling system, including an evaporative media pad and water distribution system;

[0024] FIG. 2 shows a close-up view of a portion of an evaporative media pad with reduced internal spacing; and

[0025] FIG. 3 shows a cross-sectional view of a sheet of an evaporative media pad with reduced internal spacing.

DETAILED DESCRIPTION

[0026] The system and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

[0027] As used herein, relational terms, such as first and second, top and bottom, and the like, may be used solely to distinguish one entity or element from another entity or element without necessarily requiring or implying any physical or logical relationship or order between such entities or elements.

[0028] Referring now to FIG. 1, a portion of an exemplary evaporative cooling system is shown. The evaporative cooling system 10 generally includes one or more contact bodies for providing a water-air contact surface. In one embodiment, the contact body is an evaporative media pad 12. The evaporative cooling system 10 also includes a water distribution system 14. The water distribution system 14 includes a water distribution element 16 above the evaporative media pad 12, which includes one or more nozzles or apertures (not shown), a water source 18, and a water collection reservoir 20 beneath the evaporative media pad. In this configuration, water is delivered to the upper surface of the evaporative media pad 12 from the water distribution element 16, water flows downward through the evaporative media pad 12 by gravity distribution, then flows out of the bottom of the evaporative media pad 12 and into the water collection reservoir 20. Water is then recirculated through the water distribution system 14 to the water distribution element 16 and/or is drained from the system 10. Although the evaporative cooling system 10 is discussed herein as including water as the wetting fluid, it will be understood that another suitable fluid may be used instead of or in addition to water. Likewise, one or more additives or other compounds may be added to the water to enhance cooling efficiency and/or operation of the system 10.

[0029] Although one evaporative media pad 12 is shown in FIG. 1, the evaporative cooling system 10 may include any number and configuration of evaporative media pads 12. Each evaporative media pad 12 has a height H, width W, and thickness T. Further, as shown in more detail in FIG. 2, each evaporative media pad 12 is made up of a plurality of sheets or layers 22. Each sheet in formed to include a plurality of undulations or flutes 24 that are linear, or at least substantially linear, and extend across an entirety of the sheet 22 (that is, from one edge of the sheet 22 to another edge of the sheet 22) at an angle to the edges of the sheet 22. When the evaporative media pad 12 is assembled, the flutes 24 create air channels 26 through the evaporative media pad 12. In one embodiment, the sheets 22 are arranged such that the flutes 24 extend of adjacent sheets 22 extend in opposite directions to create a cross-flow arrangement of air channels 26. Put another way, the sheets 22 are arranged such that the flutes 24 have alternating angles of incidence on the horizontal and do not coincide. FIG. 3 shows a close-up view of a portion of the evaporative media pad 12, with a portion of a first sheet 22 and a portion of a second sheet 22 removed so the relationship of the flutes 24 of adjacent sheets 22 can be seen. The flutes 24 of adjacent sheets 22 may extend at the same angle or at different angles from the straight edge of the sheet 22. In one embodiment, the flutes 24 of the first sheet 22 have a first angle of incidence .sub.1 and the flutes 24 of the second or adjacent sheet 22 have a second angle of incidence .sub.2 that is different than the first angle of incidence .sub.1. In one embodiment, the flutes 24 with the steepest angles are presented to the flow of the supply air to provide the greatest amount of water-air contact and to help prevent water droplet carryover. The flutes may have any suitable angle to the horizontal, such as 15, 30, 45, 60 , or 75. The sheets 22 are composed of any suitable material, such as cellulose paper, cellulose composite, natural fibers, wood, plastic, polyvinylchloride (PVC), glass, and/or metal.

[0030] Referring now to FIG. 3, a cross-sectional view of a sheet 22 of the evaporative media pad 12 of FIG. 2 is shown. As described above, each sheet 22 is formed to include a plurality of flutes 24, which function as air channels 26 when the evaporative media pad 12 is assembled. The horizontal line in FIG. 3 represents an adjacent sheet 22, which, although not shown, also includes a plurality of flutes 24. The sheets 22 are arranged such that the flutes 24 of adjacent sheets 22 are in contact with each other. Each flute 24 has a flute height H.sub.F. The flute height H.sub.F is a distance between the highest point 28 of the interior of the flute 24 (zenith point) extending in a first direction from the plane 30 in which the sheet 22 lies and the lowest point 32 of an adjacent flute 24 (nadir point) extending in a second direction opposite the first direction from the plane 30 in which the sheet 22 lies. Although FIG. 3 shows points 32 as being the lowest point of a flute 24, it will be understood that this is also be the highest point 28 of that flute 24 when the sheet 22 is rotated by 180. So, put another way, the flute height H.sub.F is the distance between the highest points 28 of adjacent flutes 24. When the evaporative media pad 12 is assembled, the flute height H.sub.F helps determine the overall size of the air channel 26 formed between adjacent sheets 22. The exact size, or inner diameter, of the air channel 26 will vary throughout the length of the air channel 26, depending on the positions of the adjacent flutes 24 defining the air channel 26. Thus, a larger flute height H.sub.F will produce larger air channels through the evaporative media pad, thereby increasing the air flow volume and velocity potential therethrough. However, having larger air channels also reduces the evaporative media pad's saturation potential and a larger air flow velocity causes an increased pressure drop across the evaporative media pad. Pressure drop is a term used to describe a resistance to air flow, and the greater the pressure drop, the more energy the system requires to preserve or achieve a desired air flow rate.

[0031] Industry standards for currently known evaporative media pads are a flute height of approximately 5 mm or approximately 7 mm. In contrast, the evaporative media pad 12 of the present Application has a flute height H.sub.F of 4.5 mm or less and, in particular, a flute height H.sub.F of 4 mm or less. In one embodiment, the flute height H.sub.F is between 3 mm and 4.5 mm. In one embodiment, the flute height H.sub.F is between 3.5 mm and 4.25 mm. In one embodiment, the flute height H.sub.F is between 3.75 mm and 4 mm. The reduced flute height H.sub.F, and therefore reduced internal spacing, of the evaporative media pad 12, increases the saturation efficiency of the evaporative media pad 12. This increased volume of water retained by the evaporation media pad 12 allows for an increased amount of evaporation and, therefore, a higher cooling efficiency by the evaporative cooling system 10.

[0032] Further, the reduced internal spacing of the evaporative media pad 12 provides an increased surface area over which air and water are brought into contact, thereby increasing evaporation. Still further, the reduced internal spacing of the evaporative media pad 12 provides a reduced boundary layer thickness. The thickness of a boundary layer of air or vapor on the surfaces of the air channels 26 may impede or reduce heat transfer, and therefore affects the cooling efficiency and of the evaporative cooling system 10. The reduced internal spacing of the evaporative media pad 12 results in a slight increase in pressure drop within; however, the increased surface area and decreased boundary layer thickness nonetheless provide increased saturation efficiency and, therefore, cooling performance disproportionally to the power or energy required to overcome the increase in pressure drop. Put another way, the combination of the increased saturation efficiency, increased evaporation area (surface area), and reduced boundary layer thickness provide a multiplier effect that allows the evaporative cooling system 10 using the evaporative media pads 12 with decreased internal spacing to perform more efficiently than currently known systems operating at the same input power.

[0033] It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described herein above. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. A variety of modifications and variations are possible in light of the above teachings without departing from the scope and spirit of the invention, which is limited only by the following claims.