Evaporative cooler for a gas turbine engine

The present disclosure relates to an evaporative cooler including first and second trays each having a longitudinal axis. Each tray includes a bottom wall and two side walls that project upward from the bottom wall and extend generally parallel to the longitudinal axis of each tray. Each tray also includes two end walls that project upward from the bottom wall and extend between the side walls. Each tray further includes spaced apart cooler media retaining members that are generally parallel to the longitudinal axis of each tray. The trays are positioned in an end-to-end relationship such that the longitudinal axes of the trays are generally aligned with one another, and one of the end walls of the first tray is positioned adjacent to one of the end walls of the second tray. The evaporative cooler also includes an elongated clip adapted to extend the between the adjacent end walls of the first and second trays for inhibiting water leakage between the adjacent walls.

FIELD OF THE INVENTION
 The present invention relates generally to evaporative coolers. More
 particularly, the present invention relates to evaporative coolers for use
 in gas turbine intake air systems, and to methods for assembling
 evaporative coolers.
 BACKGROUND OF THE INVENTION
 A gas turbine engine works more efficiently as the temperature of the
 intake air drawn into the gas turbine decreases. Turbine efficiency is
 dependent upon the temperature of the intake air because turbines are
 constant volume machines. The density of the intake air increases as the
 temperature of the intake air drops. Consequently, by decreasing the
 temperature of the intake air, the mass flow rate to the turbine is
 increased which increases the efficiency of the turbine.
 Evaporative cooling is an economical way to reduce the temperature of the
 intake air drawn into the turbine. An evaporative cooler commonly includes
 a plurality of vertically stacked volumes of cooler media. A distribution
 manifold disperses water over the tops of the volumes of cooler media. The
 water is drawn from a sump, distributed over the volumes of media by the
 distribution manifold, and then recycled back to the sump. Intake air for
 the gas turbine flows through the volumes of cooler media. As the water
 falls or flows through the volumes of cooler media, the air passing
 through the media evaporates some of the water. The evaporation process
 removes some energy from the air, thereby reducing the temperature of the
 air.
 SUMMARY OF THE INVENTION
 One aspect of the present invention relates to an evaporative cooler
 including first and second trays each having a longitudinal axis. Each
 tray includes a bottom wall and two side walls that project upward from
 the bottom wall and extend along the lengths of the trays. Each tray also
 includes two end walls that project upward from the bottom wall and extend
 between the side walls along the widths of the trays. The trays
 additionally include spaced-apart cooler media retaining members that are
 generally parallel to the side walls. The first and second trays are
 positionable in an end-to-end relationship such that the longitudinal axes
 are generally aligned with one another, and one of the end walls of the
 first tray is positioned adjacent to one of the end walls of the second
 tray. The evaporative cooler also includes an elongated clip adapted to
 extend between the first and second trays for inhibiting water leakage
 between the trays.
 Another aspect of the present invention relates to an evaporative cooler
 including a frame defining a plurality of substantially vertical bays
 aligned in a generally side-by-side relationships, and a plurality of
 vertically spaced apart, substantially horizontal levels. Trays that
 support volumes of cooler media are mounted on the frame. The trays are
 positioned in the bays of the frame with trays of common levels being
 arranged in end-to-end relationships. The evaporative cooler also includes
 elongated clips for inhibiting water leakage between end walls of the
 trays.
 A further aspect of the present invention relates to a tray for an
 evaporative cooler. The tray includes a modular tray body sized for
 mounting in a bay of an evaporative cooler frame. The tray body includes a
 longitudinal axis. The tray body also includes a bottom wall, and two side
 walls that project upward from the bottom wall and extend along a length
 of the tray body. The tray further includes two end walls that project
 upward from the bottom wall and extend along a width of the tray body. The
 tray additionally includes spaced-apart cooler media retaining members
 that are generally parallel with respect to the side walls. The
 spaced-apart cooler media retaining members define a gap sized and shaped
 for receiving a portion of a volume of cooler media.
 Still another aspect of the present invention relates to a method for
 assembling an evaporative cooler. The method includes the step of
 providing a frame. The method also includes the step of providing first
 and second trays each having a separate longitudinal axis. Each tray
 includes a bottom wall and two side walls that project upward from the
 bottom wall and extend generally parallel to the longitudinal axis of each
 tray. Each tray also includes two end walls that project upward from the
 bottom wall and extend between the side walls. The trays additionally
 include spaced-apart cooler media retaining members that extend generally
 parallel to the longitudinal axis of each tray. The method further
 includes the step of securing the first and second trays to the frame in
 an end-to-end relationship such that the longitudinal axis of the first
 tray aligns with the longitudinal axis of the second tray, and one of the
 end walls of the first tray is positioned adjacent to one of the end walls
 of the second tray. Finally, the method includes the step of placing an
 elongated clip over a gap defined between the adjacent end walls of the
 first and second trays.
 A variety of advantages of the invention will be set forth in part in the
 description which follows, and in part will be apparent from the
 description, or may be learned by practicing the invention. It is to be
 understood that both the foregoing general description and the following
 detailed description are exemplary and explanatory only and are not
 restrictive of the invention as claimed.

DETAILED DESCRIPTION
 Reference will now be made in detail to exemplary aspects of the present
 invention that are illustrated in the accompanying drawings. Wherever
 possible, the same reference numbers will be used throughout the drawings
 to refer to the same or like parts.
 As described in the background of the invention, evaporative cooling is an
 economical way to reduce the temperature of the intake air drawn into a
 gas turbine. In operating an evaporative cooler, it is important to
 prevent the evaporative cooling water from reaching the gas turbine. If
 water from the evaporative cooler does reach the gas turbine, the gas
 turbine can be damaged.
 Conventional evaporative coolers commonly include multiple levels of trays
 for supporting volumes of evaporative cooler media. The trays of each
 level are arranged in end-to-end relationships with respect to one
 another. Gaps or spaces are formed between the ends of the trays. If the
 gaps or spaces are not sealed, water is likely to leak between the trays
 and migrate downstream toward the gas turbine. To prevent leakage, the
 prior art teaches welding the ends of the trays together. Such a welding
 process is typically a time consuming endeavor. This is particularly true
 if precise alignment cannot be achieved between adjacent trays.
 To overcome the above identified problem, one aspect of the present
 invention relates to using clips to prevent water leakage between adjacent
 trays. In certain embodiments, the clips can be separate pieces from the
 trays. In other embodiments, the clips can be integrally formed with at
 least one of the adjacent trays.
 The use of clips provides numerous advantages over conventional welding.
 For example, clips can be mounted between two trays in a fraction of the
 time it takes to weld two trays together. Also, clips can be used to
 prevent leakage between trays, even if precise alignment is not achieved
 between the trays. Furthermore, the use of clips provides greater
 flexibility in the types of materials that can be used to manufacture the
 trays. For example, by eliminating the need for welding the ends of the
 trays, the trays can be made of a metal material or an alternative
 material such as plastic. The use of plastic material is advantageous over
 metal because plastic is lighter and less expensive than metal. The clips
 can also be made of any number of different types of materials such as
 metal or plastic. The following paragraphs describe one particular
 evaporative cooler that includes features that are examples of the broad
 inventive aspect described above.
 FIGS. 1A and 1B schematically illustrate an embodiment of an evaporative
 cooler 20 constructed in accordance with the principles of the present
 invention. The evaporative cooler 20 is adapted for cooling intake air
 that is drawn into a gas turbine 22. As shown in FIG. 1A, warm air 24
 flows into the left side of the cooler 20, while cooled air 26 exits the
 right side of the cooler 20. The cooled air 26 flows through a turbine air
 intake system to the turbine 22.
 As shown in FIGS. 1A and 1B, the evaporative cooler 20 includes a plurality
 of vertically stacked volumes of cooling media 28. The volumes of cooling
 media 28 are supported on trays 30, 31. The trays 30 are collection trays
 and function to collect water that drains downward through the volumes of
 cooling media 28. The trays 31 are flow-through trays that support volumes
 of cooling media 28, but have openings for allowing water to pass through
 the trays 31. The trays 30, 31 are preferably connected to a rigid frame
 work (not shown in FIGS. 1A and 1B) that holds the trays 30, 31 and
 volumes of cooling media 28 in vertically stacked alignment.
 The volumes of cooling media 28 can be made of any type of material
 conventionally used in evaporative coolers. For example, the cooling media
 can comprise a honeycomb of cellulose based product with resins to enhance
 rigidity. Suitable cooling media are sold by Munters Corporation of Fort
 Myers, Fla.
 The evaporative cooler 20 also includes a sump or reservoir 32 for holding
 a volume of water 34. The reservoir 32 preferably has a volume that is at
 least ten percent the total volume occupied by the volumes of cooling
 media 28. In use of the evaporative cooler 20, the water 34 from the
 reservoir 32 is circulated through the volumes of cooling media 28. As the
 warm air 24 flows through the volumes of cooling media 28, the air
 evaporates some of the water that is being circulated through the cooling
 media 28. The evaporation process removes energy from the air, thereby
 reducing its temperature.
 To circulate the water 34 through the volumes of cooling media 28, the
 water 34 is pumped upward from the reservoir 32 through a manifold flow
 line 36. The manifold flow line 36 conveys the water 34 to a plurality of
 manifolds 38. The manifolds 38 include a plurality of upwardly facing
 spray orifices for spraying the water 34 in an upward direction. As best
 shown in FIG. 1A, the water 34 is sprayed from the manifolds 38 in an
 upward direction against curved dispersion plates 40. After being
 dispersed by the dispersion plates 40, the water 34 flows downward through
 the volumes of cooling media 28 via gravity and is collected in the
 collection trays 30. From the collection trays 30, the water 34 flows
 downward via gravity through a return line 42 that conveys the water 34
 back to the reservoir 32. While a single return line 42 is schematically
 shown, it will be appreciated that multiple return lines can also be used.
 For example, separate return lines can be used for each column or bay of
 the evaporative cooler 20.
 FIG. 2 illustrates an evaporative cooler 50 that is an embodiment of the
 present invention. The evaporative cooler 50 includes a frame 52 defining
 a plurality of substantially vertical bays 54 aligned in generally
 side-by-side relationships. The frame 52 also defines a plurality of
 vertically spaced-apart, substantially horizontal levels. For example, as
 shown in FIG. 2, the evaporative cooler 50 has seven levels that have been
 assigned, from bottom to top, reference numerals 58, 60, 62, 64, 66, 68
 and 70. While FIG. 2 shows that the evaporative cooler 50 includes four
 bays 54 and seven separate levels, it will be appreciated that the present
 invention is not limited to such a configuration and that any number of
 bays or levels can be used.
 The evaporative cooler 50 includes a plurality of separate, modular trays
 that are secured to the frame 52 at the various levels 58-70. For example,
 the evaporative cooler 50 includes collection trays 72A mounted at levels
 62 and 66, flow-through trays 72B mounted at levels 60, 64 and 68, top
 trays 72C (shown in FIG. 4) mounted at level 70, and bottom trays 72D
 mounted at level 58. The collection trays 72A, the flow-through trays 72B
 and the bottom trays 72D are adapted for supporting volumes of evaporative
 cooler media. For clarity, the volumes of the cooler media are not shown
 in FIG. 2. The collection trays 72A are adapted for collecting water that
 is circulated through the volumes of cooling media, and are also adapted
 for dispersing water over the tops of the volumes of cooling media. The
 flow-through trays 72B include openings for allowing water to pass through
 levels 60, 64 and 68. Similar to the collection trays 72A, the bottom
 trays 72D are adapted for collecting water that is circulated through the
 volumes of cooling media. The top trays 72C function exclusively to
 disperse water over the tops of the volumes of cooling media.
 Referring again to FIG. 2, the evaporative cooler 50 includes manifold flow
 lines 74 that convey water from a sump 76 to levels 62, 66 and 70 of the
 evaporative cooler 50. The evaporative cooler 50 also includes return
 lines 78 for returning water from the volumes of cooling media back to the
 sump 76. As shown in FIG. 2, a separate return line 78 is located at each
 bay 54 of the evaporative cooler 50. The return lines 78 drain the water
 that is collected in the collection and bottom trays 72A, 72D, and return
 the collected water back to the sump 76.
 The evaporative cooler 50 includes grates 80 positioned at levels 58, 62
 and 66. The grates allow an operator of the evaporative cooler 50 to
 access the various levels and bays of the cooler. Ladders 82 extend
 between the grates 80.
 FIG. 3 illustrates a frame 52' that corresponds to a single bay 54 of the
 frame 52. The frame 52' is generally rectangular and includes four
 substantially vertical corner supports 84, 86, 88 and 90. A first
 substantially vertical intermediate support 92 is positioned between the
 corner supports 84 and 90, while a second substantially vertical
 intermediate support 94 is positioned between the corner supports 86 and
 88. Generally rectangular tray supports 96 are positioned at the levels
 58, 60, 62, 64, 66, 68 and 70 of the frame 52'. For example, the tray
 supports 96 are mounted between the first and second intermediate supports
 92 and 94, and the corner supports 84 and 86. The tray supports 96 include
 side members 98 that extend along lengths of the supports 96, and end
 members 100 that extend along widths of the supports 96. At levels 58, 62
 and 66, the end members 100 include inwardly projecting bottom flanges
 102. Also at levels 58, 62 and 66, the frame 52' includes generally
 rectangular grate supports 104 for securing the grates 80 to the frame
 52'. At levels 58, 60, 62, 64, 66 and 68, a generally U-shaped layer of
 caulk 93 or other resilient sealing material is positioned along the outer
 surfaces of the end member 100, the corner supports 84 and the
 intermediate supports 92. The caulk 93 forms a seal between adjacent bays
 when the cooler 50 is assembled.
 FIG. 4 shows the frame 52' with the trays 72A, 72B, 72C and 72D secured at
 the various levels 58, 60, 62, 64, 66, 68 and 70. One of the return lines
 78 is shown for draining collected water from the collection trays 72A and
 the bottom tray 72D. Volumes of cooler media 104 are schematically shown
 in FIG. 4. The volumes of cooler media 104 are supported by the collection
 trays 72A, the flow-through trays 72B and the bottom tray 72D.
 FIG. 5 is a schematic end view of the cooler 50. As shown in FIG. 5, the
 volumes of cooler media 104 are shown positioned between each of the
 levels 58-70 of the frame 52. Again, one of the return lines 78 is shown
 for draining water collected in the collection trays 72A. Also, mist
 eliminators 106 are shown mounted on levels 60 and 62 at locations
 downstream from the volumes of cooler media 104. In one particular
 embodiment of the present invention, the mist eliminators 106 are aligned
 at angles in the range of 5-10 degrees relative to vertical, with a top
 end of each mist eliminator being in close proximity to a corresponding
 filter media 104. The mist eliminators 106 can be made of any suitable
 material conventionally used in evaporative coolers. For example, the mist
 eliminators can comprise polyvinyl chloride (PVC). Suitable mist
 eliminators are sold by Munters Corporation of Ft. Myers, Fla. In use,
 mist eliminators are preferably mounted between each of the levels 58, 60,
 62, 64, 66, 68 and 70.
 FIGS. 6-9 illustrate one of the collection trays 72A in isolation from the
 frame 52. As shown in FIG. 6, the collection tray 72A is aligned along
 (i.e., generally parallel to) a central longitudinal axis 107. Generally,
 the collection tray 72A includes an upper pan portion 108 for collecting
 water that flows through the volumes of cooler media 104, and a lower
 dispersion portion 110 for dispersing water over the volumes of cooler
 media 104.
 Referring to FIG. 9, the collection tray 72A includes a bottom wall 112 and
 two oppositely disposed side walls 114 that project upward from the bottom
 wall 112 and extend generally parallel to the longitudinal axis 107. As
 shown in FIG. 6, the upper pan portion 108 also includes two end walls 116
 that project upward from the bottom wall 112 and extend between the side
 walls 114. The end walls 116 are oriented generally transverse with
 respect to the longitudinal axis 107. The side walls 114 and the end walls
 116 intersect or meet at corner edges 118.
 For facilitating mounting the collection tray 72A on the frame 52, the tray
 72A includes side flanges 120 that project transversely outward from the
 side walls 114. Similarly, the tray 72A includes end flanges 122 that
 project transversely outward from upper edges of the end walls 116. As
 best shown in FIG. 7, the side flanges 120 define elongated openings 124
 for use in bolting or otherwise securing the side flanges 120 to the side
 members 98 of the frame 52. The elongated openings 124 are elongated in a
 dimension generally transverse with respect to the longitudinal axis 107
 of the tray 72A. The elongated openings 124 are advantageous because they
 allow the mounting position of the tray 72A to be laterally adjusted (e.g.
 adjusted in the direction transverse with respect to the longitudinal axis
 107) relative to the frame 52. The ability to laterally adjust the
 position of the tray 72A relative to the frame 52 assists in achieving
 longitudinal alignment of the trays 72A that are mounted on common levels.
 The bottom wall 112 includes a continuous top surface that extends between
 the side walls 114 and also between the end walls 116. The bottom wall
 112, the side walls 114, and the end walls 116 cooperate to form a pan
 arranged and configured to hold water. As shown in FIGS. 7-9, the pan
 includes a drain opening 126 defined through the bottom wall 112 for
 allowing collected water to be drained from the pan. Preferably, the drain
 opening 126 is connected in fluid communication with one of the return
 lines 78 of the evaporative cooler 50 such that water collected in the pan
 is drained through the return line 78 and returned to the sump 76.
 The upper pan portion 108 also includes spaced apart cooler media retaining
 members 128 that extend along (i.e., are generally parallel to) the
 longitudinal axis 107 between the end walls 116. The retaining members 128
 define a channel 129 for receiving a lower end of one of the volumes of
 cooling media 104. As shown in FIG. 9, the retaining members 128 include
 base ends 130 connected to the bottom wall 112, and top ends 132 that
 taper outward to facilitate inserting volume of cooler media within the
 channel 129 between the retaining members 128. Support members 134 project
 laterally outward from inner surfaces of the retaining members 128. The
 support members 134 have top surfaces 136 that are substantially parallel
 to the bottom wall 112 and are aligned slightly above the top edges of the
 end walls 116. In use, a volume of cooler media is inserted within the
 channel 129 between the retaining members 128 such that a lower portion of
 the volume of cooler media rests upon the support members 134. In this
 manner, the support members 134 hold the volume of cooler media above the
 bottom wall 112 of the pan portion 108.
 As shown in FIG. 6, the cooler media retaining members 128 have ends 138
 that are connected to inner surfaces of the end walls 116 to enhance the
 structural integrity of the tray 72A. The ends 138 include upper
 shoulders, cut-away portions or notches 140 that provide upper clearance
 gaps 142 between the ends 138 of the retaining members 128, and the inner
 surfaces of the end walls 116.
 The upper pan portion 108 also includes a mist eliminator retaining bracket
 144. The bracket 144 is supported above the top edges of the end walls
 116, and defines a channel 146 that extends generally parallel to the
 longitudinal axis 107 between the end walls 116 of the pan portion 108. As
 shown in FIG. 9, the channel 146 is sized to receive a lower end of one of
 the mist eliminators 106. A lower wall 148 is inclined with respect to
 horizontal in order to align the mist eliminator 106 at an oblique angle
 with respect to vertical.
 The dispersion portion 110 of the collection tray 72A is secured beneath
 the bottom wall 112 of the pan portion 108 by conventional techniques such
 as bolts 150. As shown in FIG. 9, the dispersion portion 110 includes a
 curved dispersion plate 152 positioned above a manifold 154. As previously
 described with respect to the embodiment of FIGS. 1A and 1B, the manifold
 154 preferably includes a plurality of upwardly directed orifices for
 spraying water upward against the lower surface of the curved dispersion
 plate 152. The dispersion plate 152 disperses the water from the manifold
 154 across the top of one of the volumes of cooler media 104 that is
 mounted below the dispersion plate 152. To further enhance dispersion, a
 conventional dispersion pad (not shown) can be positioned between the
 dispersion plates 152 and their corresponding volumes of cooler media 104.
 The top of one of the volumes of cooler media 104 is retained beneath the
 curved dispersion plate 152 by a pair of downwardly projecting retaining
 members 156. Lower ends 158 of the retaining members 156 taper toward one
 another. A top end of the cooler media 104 is inserted between the
 retaining members 156.
 The dispersion portion 110 also includes downwardly projecting retaining
 members 160 defining a channel 162 sized for receiving a top end of one of
 the mist eliminators 106. The channel 162 extends along the longitudinal
 axis 107.
 The dispersion portion 110 further includes substantially parallel end
 walls 164 that are generally transversely aligned with respect to the
 longitudinal axis 107. As shown in FIGS. 6 and 9, at least one of the ends
 walls 164 includes a resilient sealing member or strip 166 for forming a
 fluid tight seal between the dispersion portions 110 when the collection
 trays 72A are aligned end-to-end with respect to one another. The sealing
 strips 166 preferably include straight portions 168 that extend along the
 lower edges of the end walls 164, and curved portions 170 that extend
 along the curved dispersion plates 152. The sealing strips 166 can be made
 of any type of resilient material such as rubber or a closed-cell type of
 foam. In certain embodiments, the resilient material can cover the entire
 outer surface of the end walls 164.
 The collection trays 72A are preferably mounted at levels 62 and 66 of the
 frame 52. Preferably, the collection trays 72A of common levels are
 arranged in end-to-end relationships with one another such that the
 longitudinal axes 107 are in general alignment with one another. To mount
 the collection trays 72A on the frame 52, the trays 72A are placed on the
 tray supports 96 such that the side flanges 120 rest upon the side members
 98 of the tray supports 96, the bottom walls 112 seat upon the bottom
 flanges 102 of the tray supports 96, and the end flanges 122 seat upon the
 end members 100 of the tray supports 96. Once the collection trays 72A
 have been placed on the tray supports 96, the collection trays 72A are
 preferably connected to the tray supports 96 through the use of connecting
 members such as bolts that are inserted through the elongated openings 124
 and secured to the side members 98 of the tray supports 96. The elongated
 openings 124 allow the trays 72A to be laterally adjusted relative to one
 another to achieve longitudinal alignments.
 After the trays 72A have been secured to the frame 52, elongated clips are
 preferably mounted over adjacent end walls 116 of the trays 72A to inhibit
 leakage between the trays 72A. For example, FIG. 10 shows two of the trays
 72A positioned in end-to-end alignment with a clip 178 mounted between the
 trays 72A. As shown in FIG. 11, the end walls 116 of the trays 72A are
 positioned adjacent to one another, bottom walls 112 of the trays 72A are
 seated upon the bottom flanges 102 of the tray supports 96, and the end
 flanges 122 are seated upon the side members 98 of the tray supports 96.
 The end flanges 122 are preferably aligned in substantially the same
 horizontal plane. A space 180 is formed between free ends of the end
 flanges 122. The clip 178 is mounted over the adjacent end walls 116 and
 covers the space 180. As shown in FIG. 10, the clip 178 preferably has a
 length generally equal to the length of the end walls 116. The space 180
 is also sealed by the layer or bead of caulk 93.
 Referring back to FIG. 11, the clip 178 has a generally U-shaped cross
 section and includes two substantially parallel leg portions 182 connected
 by a bridge portion 184. The bridge portion 184 is preferably transversely
 aligned with respect to the leg portions 182. As shown in FIG. 11, the
 clip 178 defines a channel 186 in which the adjacent end walls 116 of the
 trays 72A are received. The bridge portion 184 of the clip 178 rests upon
 the end flanges 122, while the leg portions 182 extend along interior
 surfaces 188 of the end walls 116. Clearance for the legs 182 is provided
 by the clearance gaps 142 formed between the retaining members 128 and the
 end walls 116. In this manner, the clip 178 straddles the adjacent end
 walls 116.
 FIGS. 12-15 illustrate one of the flow-through trays 72B in isolation from
 the frame 52. It will be appreciated that the flow-through tray 72B
 includes many of the same elements or features as the collection tray 72A
 of FIGS. 6-9. In this regard elements of the flow-through tray 72B that
 have been previously described with respect to the collection tray 72A
 will be assigned common reference numerals with the addition of
 apostrophes to distinguish the embodiments.
 The flow-through tray 72B extends along a longitudinal axis 107' and
 includes an upper portion 172 positioned above a lower portion 174. The
 upper portion 172 includes a bottom wall 112' and two substantially
 parallel side walls 114' that project upward from the bottom wall 112' and
 extend along the longitudinal axis 107'. The upper portion 172 also
 includes end walls 116' that extend transversely between the side walls
 114' and intersect the side walls 114' at corner edges 118'. Side flanges
 120' project transversely outward from the side walls 114', while end
 flanges 122' project transversely outward from the end walls 116'. The
 side flanges 120' define elongated openings 124' for bolting or otherwise
 securing the flow-through tray 72B to the frame 52.
 The upper portion 172 of the flow-through tray 72B also includes two spaced
 apart cooler media retaining members 128'. As shown in FIG. 15, the cooler
 media retaining members 128' define a channel 129' for receiving a lower
 portion of one of the volumes of cooler media 104. Support members 134'
 project from the retaining members 128' into the channel 129'. The support
 members 134' are adapted for supporting the lower end of the volume of
 cooler media within the channel 129' such that the bottom of the cooler
 media is spaced from the bottom wall 112' of the flow-through tray 72B.
 The cooler media retaining members 128' of the upper portion 172 have ends
 138' that are connected to interior surfaces of the end walls 116'. As
 shown in FIG. 17, the ends 138' include cut away portions, shoulders or
 notches 140' that define clearance gaps 142 between the ends 138' and the
 interior surfaces of the end walls 116'.
 As shown in FIG. 15, the bottom wall 112' of the tray 72B defines a
 flow-through opening 176 positioned directly beneath the channel 129'
 defined by the cooler media retaining members 128'. The flow-through
 opening 176 extends completely through the bottom wall 112' and is
 elongated in a direction extending along the longitudinal axis 107'. The
 flow-through opening 176 allows water to pass through the bottom wall 112'
 such that water is not accumulated at the upper portion 172 of the
 flow-through tray 72B.
 The upper portion 172 of the flow-through tray 72B also includes a bracket
 144' having an upwardly opening channel 146' adapted for receiving a lower
 end of one of the mist eliminators 106.
 The lower portion 174 of the tray 72B includes retaining members 156'
 positioned on opposite sides of the flow-through opening 176. The
 retaining members 156' project downward from the bottom wall 112' and
 define a channel sized for receiving a top end of one of the volumes of
 cooler media 104.
 The lower portion 174 also includes spaced-apart retaining members 160'
 that project downward from the bottom wall 112'. The retaining members
 160' define a channel 162' sized for receiving a top end of one of the
 mist eliminators 106.
 The flow-through trays 72B are preferably mounted on the frame 52 at levels
 60, 64 and 68. Preferably, the flow-through trays 72B of common levels are
 positioned in an end-to-end relationship such that the longitudinal axes
 107' are aligned with one another. For example, the flow-through trays of
 level 60 are positioned in an end-to-end relationship, the flow-through
 trays of level 64 are positioned in an end-to-end relationship, and the
 flow-through trays of level 68 are positioned in an end-to-end
 relationship. To secure the flow-through trays 72B to the frame 52, the
 trays 72B are placed on and supported by the generally rectangular tray
 supports 96 of the frame 52. For example, the trays 72B are positioned on
 the frame 52 such that the end flanges 122' rest upon the end members 100
 of the tray supports 96, while the side flanges 120' rest upon the side
 members 98 of the tray supports 96. Preferably, the side flanges 120' are
 bolted to the side members 98 by bolts that extend through the elongated
 openings 124'. The elongation of the openings 124' allows the position of
 the flow-through trays 72B to be laterally adjusted relative to the frame
 52 in order to achieve general longitudinal alignment between the
 flow-through trays 72B.
 FIG. 16 shows two of the trays 72B positioned in an end-to-end relationship
 with respect to one another. One of the clips 178 is positioned between
 the trays 72B. The clip 178 has a length which is preferably generally
 equal to the length of the end walls 116'. As shown in FIG. 17, the trays
 72B are positioned such that the end walls 116' of the trays 72B are
 oriented adjacent to one another. The end flanges 122' of the end walls
 116' are seated upon the end members 100 of the tray supports 96 and are
 preferably aligned in a common horizontal plane. A space or gap 180' is
 defined between free ends of the end flanges 122'. The space 180' is
 covered by the clip 178 such that water is inhibited from leaking between
 the trays 72B. The space 180' is also sealed by a layer or bead of
 resilient material 93' such as caulk.
 It will be appreciated that the top trays 72C and the bottom trays 72D are
 modified versions of the collection trays 72A. For example, the top trays
 72C have the same structure as the dispersion portions 110 of the
 collection trays 72A, but do not include the pan portions 108. Similarly,
 the bottom trays 72D have the same configuration as the pan portions 108
 of the collection trays 72A, but do not include the dispersion portions
 110.
 With regard to the foregoing description, it is to be understood that
 changes may be made in detail, especially in matters of the construction
 materials employed, and the size, shape and arrangement of the parts
 without departing from the scope of the present invention. For example,
 the number of media volumes, manifolds and pumps can be varied from those
 specifically illustrated. It is intended that the specification and the
 depicted aspects be considered exemplary only, with the true scope and
 spirit of the invention being indicated by the broad meaning of the
 following claims.