Note: Descriptions are shown in the official language in which they were submitted.
;~2~
1 PLASTIC FILL SHEET FOR
WATER COOLING TOWER WITH AIR GUIDING SPACERS
Background of the Invention
1. Eield of the Invention
This invention relates to water cooling
towers and especially an improved film fill assembly
for use in an evaporative type cooling tower.
In particular, the invention is concerned
~ 10 with a film fill assembly made of packs of fill
! sheets arranged in vertically oriented, side-by-side
relationship. The individual sheets are each formed
to present not only a chevron-patterned central
air-water contact zone, but also to define corru-
gated upper marginal sections which mutually cooper-
ate with the same sections of adjacent sheets to
provide for even distribution of hot water over the
plan area of the fill assembly. Each of the sheets
is further provi-ded with partial honeycomb side
marginal portions which are mutually cooperable in
an assembled fill pack to define passages which
control the path of inflowing or outflowing cooling
air or the flow of air between horizontally aligned
packs. An integral hori~ontally extending corru-
gated section may be provided if desired between the
upper and lower edges of each sheet to effect redis-
tribution of the hot water as it flows downwardly
over the main air-water contact zone oE respective
fill sheets.
The unique shape of the film fill sheets
not only permits fabrication of the individual
sheets using conventional vacuum forming techniques,
but also allows minimization of the number of dif-
ferent types of sheets which must be formed and
s
1 thereafter assembled to present a pack which retains
required thermal performance characteristics without
untoward air pressure drop.
2. Description of the Prior Art
Water cooling tower fill assemblies for
many years typically were made up of a series of
horizontally oriented, flat splash bars located in
horizontal and vertically spaced relationship in
disposition such that hot water gravitating through
the fill impacted on the bars and was broken up into
droplets to increase the surface area of the water
and thereby increase cooling efficiency.
- In recent years, film fill packs made up
of vertically positioned, horizontally spaced syn-
thetic resin sheets have replaced the splash bars
because of the flame retardant nature of such mate-
rials, the decreased size of the overall fill assem-
bly thus lowering pumping heights, and minimization
of the overall size of towers incorporating film
fill units.
Film fill design parameters include the
requirements of spreading the water out over the
surface of the fill sheets in a thin film for maxi~
mum surface area, retarding of the gravitational
flow of the water to the extent feasible to assure
maximum exposure of the water to cooling air, and
providing turbulent airflow without excessive air
pressure drop.
To these ends, each face of sheet Eill
members forming multiple-sheet fill assemblies are
oEten formed with sets of zig-zag chevron patterns
which effectively increase the available surface
area of the fill and decrease the velocity of flow
of the descending films of water. The chevron
pattern also lends itself to being produced by
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l conventional vacuum-forming techniques, long
employed in the plastics industry. During the
vacuum-forming process, selected areas of the ini-
tially flat, synthetic resinous sheet are subjected
to negative pressures to draw the areas into cavi-
ties of a forming die, thereby creating the desired
pattern of peaks and valleys on one face of the
sheet which each define a respective valley and peak
on the opposite face of the sheet. In this regard,
exemplary chevron pattern film fill sheets are
depicted and described in U.S. Patent Nos.
! 3,733,063, 4,320,073 and 4,548,766, all of which are
assigned to the assignee of the present application.
Moreover, it is highly important to main-
tain the required spatial relationship between the
chevron-patterned cooling zones of adjacent sheets
of the fill assembly in order to avoid development
of undue localized air pressure drops which can
significantly decrease the thermal performance of
the film fill. During operation of a cooling tower,
it has been found that when thin synthetic resin
sheets assembled into a fill are loaded with hot
water, the sheets sometimes have a tendency to warp,
bend or buckle thus reducing the cross~sectional
area of the adjacent space available for passage of
air. Additionally, because the relatively thin
sheets are normally fashioned of a thermoplastic
such as polyvinyl chloride, the sheets have an
increased tendency to sag and warp under the normal
operating conditions of the cooling tower.
At the top of the fill pack, marginal top
edge portions of sheets also tend to deflect toward
each other on a random basis thus precluding equal
distribution of hot water across the full plan area
of the film fill assembly and hindering uniform
2425
l gravitational flow of water downwarclly across
opposed faces of each sheet of the fill pack.
In the past, integral, individual spacers
have often been formed in the film ill sheets in an
effort to maintain uniform spacing of the sheets
throughout the pack. One example of such spacers
is shown in the aforementioned U.S. Patent No.
4,320,073 wherein outwardly extending indexing units
are disposed at spaced locations throughout the
chevron-shaped cooling zones of the sheet member for
engagement with respective recess-defining walls
located on the next adjacent sheet. While such
indexing units have been found to be satisfactory
when present in sufficient numbers for maintaining
the desired spacing between adjacent sheets in areas
within the chevron-patterned cooling zones, the
spaced, integral indexing units of the cooling zones
cannot be relied upon to entirely prevent warpage of
top marginal edge portions of each sheet. Further-
more, if an adequate number of the spacers is pro--
vided to insure against deflection of the fillsheets, the spacers represent an impedence to air-
flow which alters the thermal performance of the
fill pack.
For the most part, film fill assemblies
have been used in small package-type water cooling
towers. Recently, however, more and more emphasis
has been placed on adapting such film fill assem-
blies for use in larger, industrial-type water
cooling towers. However, the characteristics and
construction of conventional vacuum forming machines
limit for practical purposes the width of each sheet
which may be formed on such equipment. Typically,
this is a dimension oE no more than about four feet.
As a result, two packs of fill members are often
_~_
9L25
1 arranged in side-by-side relationship in the direc-
tion of airflow to present a fill assembly which is
of adequate dimensions between the air inlet and the
air outlet. The outwardmost edge portions of the
outboard fill pack sheets are normally formed to
present an upright series of air inlet louvers,
while the marginal, innermost edge portions of the
inboard fill pack may be formed to present drift
eliminator structure for separating entrained water
droplets from the currents of air flowing out of the
fill assembly.
Although these inclined air inlet louvers
and drift eliminator components presenting air inlet
and air outlet passages are of convoluted shape
which prevents for the most part suhstantial deflec-
tion and warpage of the upright outermost edge
portions of the fill sheets under normal hot watertemperature conditions, the same has not been the
case as to the upright edges of the fill packs which
are in directly abutting, proximal relationship.
However, there is also a significant need to pre-
clude warpage and deflection of the edge portions of
the fill packs which are in abutting relationship
since uniform transfer of air from the outboard fill
pack into the inboard fill pack is essential for
maximum thermal performance efficiency.
Finally, it has often been necessary to
provide a deck assembly or other water distribution
structure in direct overlying relationship to the
upper faces of the film fill packs underneath the
hot water distribution deck or distributor apparatus
in order to assure uniform loading of water across
the entire plan area of the fill. Even with the
attendant extra expense incurred by the provision of
distribution structure overlying the film fill
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l~Z~25
l packs, the incorporation of such added equipment
often has not resolved the problem because of warp-
age and deflection of the upper edges of the Eilm
fill sheets thus preventing the water from flowing
in substantially equal proportional amounts into all
of the spaces between proximal fill sheets rather
than channeling into certain of the passages depend-
ing upon the actual extent of the open areas pre-
sented at the top of the film fill packs.
Summary of the Invention
In view of the factors set forth above, it
is a primary object of the present invention to
provide structure for reliably maintaining openings
of equal size between the edges of the sheets of a
multiple-sheet film fill assembly, particularly in
the regions thereof which directly receive hot water
delivered onto the film fill packs, and in adjacent,
abutting areas of packs which are located in tandem
relationship in the direction of airflow through the
cooling tower. The present invention provides
spacing and water dispersing structure which extends
along the top marginal edge portions of each sheet
as well as horizontally along intermediate regions
thereof. Spacing and air direction structure is
incorporated in the fill sheets which extends in an
upright direction along the facing, side edge por-
tions of the sheets of adjacent packs.
More specifically, the spacing and water
dispersing structure includes a corrugated water
distribution and spacing section integrally formed
along the top edge of each sheet as well as across
the entire width of intermediate regions of each
sheet. The corrugated pattern presents a spaced
series of peaks and valleys having respective longi-
~%~?2~2~ii
1 tudinal axes which are inclined in a directiongenerally opposite to the longitudinal axes of the
facing peaks and valleys of the next adjacent
sheets. Preferably, the peaks of the corrugations
are of a length to contact the peaks of the adjacent
sheets at two spaced locations or crossings so that
sufficient stability is provided for each sheet to
avoid excessive warpage of individual sheets over
the expected lifetime of the fill assembly.
At the top of each fill pack, the corru-
gated spacing and water dispersing structure func-
tions to receive water directed onto the top of the
fill pack from overlying nozzles or orifices and
divide the same into flows which assure relatively
uniform loading of the associated regions of the
underlying, chevron-patterned cooling zones. The
corrugated configuration of the spacing structure is
such as to block the fall of water from the overly-
ing hot water distribution basin and assure conver-
sion of the separate streams or droplets of water
into water films which flow downwardly across
opposed faces of the fill sheets. In this manner,
tower efficiency is significantly improved by pre-
venting water from channeling in certain of the
spaces between adjacent sheets.
In the case where intermediate regions of
the film fill sheets are also provided with hori-
zontally extending corrugated spacer and water
dispersing sections, such corrugated sections serve
to relieve stresses which may otherwise develop in
the interior part thereof thus precluding warpage
and deflection of such portions of the sheets, as
well as maintaining the clesired interior sheet
spacings between the cooling zones of adjacent
sheets. The corrugated conEiguration of the inter~
~Z~2~
1 mediate spacing and water dispersing structure
operates to redistribute the descending films of
water and assures uniform loading of the lower part
of each fill pack.
In a preferred embodiment of the inven-
tion, the longitudinal axis of the peaks of every
other corrugated section of each sheet are inclined
at an angle of about 30 from horizontal, while the
longitudinal axis of the peaks of the remaining
sheets are inclined in an opposite direction at an
angle of about 30 from horizontal. The projected
vertical extent of each corrugation is selected so
that each peak contacts two peaks of the next adja-
cent sheet at two spaced locations or crossing
points, so that the corrugations impart adequately
stability to the pack without unduly reducing the
overall extent of the chevron-patterned main cooling
zones of respective fill sheets. The angle of
inclination of the..spacing and water dispersing
corrugations is preferably not greater than about
30 to avoid an unsatisfactory pressure drop of air
flowing through the fill packs.
The spacing and air orientation structure
which extends vertically along the directly opposed,
proximal side portions of the tandem located, adja-
cent fill packs is of a honeycomb configuration invertical section with upright wall segments of each
sheet being in contact with wall segments of the
adjacent sheets. The sheets are formed to present
smooth transitions between the chevron-patterned
3 cooling zones and the honeycomb structure, so that
air exiting the outboard fill pack is guided in a
horizontal direction for entry into the honeycomb
structure of the air inlet face of the adjacent
pack. This honeycomb structure and the transition
l surfaces reduce turbulence of air Elowing ~etween
the packs and minimizes the effect of any misalign-
ment of the sheets of each pack as may occur, for
example, when a sheet of the outboard fill pack does
not lie in a common plane with the directly adjacent
sheet of the inboard fill pack.
The cooperative effect of the horizontally
extending, corrugated spacing and water dispersing
structure as well as the honeycomb air orientation
structure extending along the adjacent edges of the
sheets of both fill packs is to maintain proper
sheet spacing around the perimeter of the sheets as
well as the boundary of each cooling zone with a
minimum of resistance to airflow through the tower.
These and other objects of the invention will become
apparent in the course of the following description
of a preferred embodiment of our invention.
srief Description of the Drawings
Figure 1 is a side elevational view of a
fill assembly constructed .in accordance with the
principles of the present invention, wherein the
assembly is comprised of two side-by-side, multiple-
sheet fill packs and wherein a portion of one sheet
of each pack has been cut away to reveal the next
adjacent sheet;
Fig. 2 is an enlarged, fragmentary, per-
spective view of a corner portion of three sheets of
the outboard fill pack depicted in Fig. 1, illu-
strating vertically extendiny spacer structure of a
honeycomb configuration, as well as horizontally
extending spacer structure of a corrugated configur-
ation;
Fig. 3 is an enlarged, fragmentary end
view of an inner, top corner portion of three sheets
s
1 of the outboard fill assembly depicted in Fig.
taken in a direction toward outer regions of the
fill pack through the honeycomb structure;
Fig. 4 is an enlarged, fragmentary, plan
view of the corner portion of the fill pack that is
depicted in Fig. 3; and
Fig. S is an enlarged, fragmentary, hori-
zontal sectional view taken through the honeycomb
structure and chevrons of the cooling zone of a
portion of the outboard fill pack shown in Fig. 1.
Detailed Descri~tion of the Drawings
Referring initially to Eig. 1, a film fill
assembly for water cooling towers is broadly desig-
nated by the numeral 10 and includes an outboard
film fill pack 12 as well as an adjacent, inboard
film fill pack 14. Although not shown, it is to be
understood that the fill packs 12, 14 are used in a
crossflow mechanical draft cooling tower having a
hot water distribution means in the form of a series
of nozzles, apertures or other means for delivering
hot water to be cooled across the plan area of the
fill assembly 10. A cold water collection basin is
conventionally provided in underlying relationship
to the film packs 12, 14.
Conventionally, a fan of the cooling tower
draws currents of air through the film packs 12, 14
in generally transverse relationship to the flow of
water descending by gravity therethrough.
The film packs 12, 14 are each in the Eorm
of a series of spaced, opposed, upright, face-to-
face alternate sheet fill members 16 and 18, and 20
and 22, respectively. Each of the sheets 16-22 is
advantageously of integral construction and prefer-
ably shaped by a vacuum forming process from a
--10--
2~;
l suitable synthetic resinous material such as poly-
vinyl chloride.
The outermost edges of the alternate
sheets 16, 18 of the outboard fill pack 12 are
formed to present a series of air inlet louvers 24
which extends along the entire height of the assem-
bly 10. In addition, the outwardmost edge portions
of the alternate sheets 20, 22 of the inboard film
fill pack 14 have a series of molded drift elimi-
nators 26 extending from the top to the bottom of
assembly 10. The louvers 24 and the eliminators 26
have respective longitudinal axes which are inclined
from horizontal for reasons as will be apparent to
those skilled in the art.
Cooling zones 28 extend across the major
extent of both faces of each of the sheets 16-22.
As depicted in Fig. 1, each of the sheets 16-20 have
been provided for illustrative purposes with two
cooling zones 28 respectively, although a greater
number of cooling zones 28 may be desirable where,
for example, the length of the parallelogram-shaped
sheets 16-22 of the fill packs 12, 14 is extended to
match the space available in larger towers.
Referring now to Figs. 1-3 and 5, the
cooling zones 28, in more detail, are comprised of a
vacuum-formed undulating, repeating pattern repre-
sented by a series of zig-zag, serpentine, chevron
defining spaced ridges 30 on opposed faces of sheets
16-22 which define respective complementally con-
figured zig-zag grooves 32 between each adjacent
pair of ridges 30. The ridges 30 and grooves 32 of
cooling zones 28 may be identical in construction to
the æig-zag ridges and grooves of the cooling zones
depicted in the aforementioned U.S. Patent No.
9,548,766, the disclosure of which is hereby ex-
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l pressly incorporated into the disclosure of the
present application.
Referring now to Figs. 1, 2 and 4, each of
the sheets 16-22 is shaped to present a top sheet
spacing and water dispersing section 34 and an
intermediate sheet spacing and air orientation
section 36, and optionally sheet spacing sections
may be provided where, for example, the vertical
length of the respective fill sheet is greater than
that which is depicted in the drawings. soth of the
sheet spacing sections 34, 36 extend substantially
across the entire width of the respective fill sheet
16-22.
The sheet spacing sections 34, 36 are
formed in a corrugated pattern integral with the
respective fill sheets 16-22 and present a spaced
series of elongated peaks 38 on each face of the
fill sheets 16-22. The peaks 38 are interconnected
by a spaced series of corresponding valleys 40, and
the peaks on one face of each fill sheet 16-22
define the valleys 40 on the opposite face thereof
and vice-versa.
The peaks 38 on each face of the sheets
16-22 extend outwardly in a horizontal direction
past the tops of the ridges 30 of the adjacent
cooling zones 28. As an example, the thickness of
the cooling zone 28 (i.e., the horizontal distance
from the top of each ridge 30 on one face of the
sheet to the top of the adjacent ridge 30 on the
opposite face of the same sheet) may be in the order
of about 0.180 inch to 0.30 inch, while the thick-
ness oE the spacing section (i.e., the horizontal
distance from the top of one peak 38 to the top of
the opposed, adjacent peak 38 on the opposite face
of the same sheet) may be in the order of approxi-
24Z~
1 mately 0.75 inch, although other dimensions are also
possible.
The longitudinal axes of each of the peaks
38 and the valleys 40 on each face of any one sheet
16-22 are oppositely inclined relative to the longi-
tudinal axes of the peaks 38 and the valleys 40 of
the adjacent face of the next adjacent sheet 16-22,
as can best be appreciated by reference to the cut-
away sections of the sheets 16, 20 which are illu-
strated in Fig. 1. The longitudinal axes of each
peak 38 and valley 40 are inclined from horizontal
at an angle preferably within the range of about 20
to about 30, and in particularly preferred embodi-
ments of the invention, the inclination of the
longitudinal axes of peaks 38 and valleys 40 is
approximately 30 from horizontal.
Viewing Fig. 4, the peaks 38 oE each face
of each sheet 16-22 are in contact with peaks 38 of
the proximal face of the next adjacent, respective
sheet 16-22 in order to retain the fill sheets at
0 regular, horizontal intervals apart and to thereby
maintain a desired pre-selected horizontal spacing
between the corresponding cooling zones 28 of the
adjacent sheets 16-22. Importantly, the smoothly
curved configuration of the peaks 38 and the oppo-
sitely inclined orientation of the peaks 38 of
adjacent fill sheets 16-22 enables the corrugated
spacing sections 34, 36 to engage the adjacent
sections 34, 36 without the need for indexing of the
sheets 16-22 in directions parallel to the planes of
extension of the latter.
Preferably, the corrugated sections 34, 36
are of such a height that the peaks 38 contact the
peaks 38 of the adjacent sheets 16-22 at two loca-
tions or crossing points in order to provide a
~2~2S
l desired amount of stability to the sheets 16-22 and
thereby to the fill packs 12, 14. By the same
token, the projected vertical extent of the corru-
gated sections 34, 36 is advantageously not greater
than is sufficient for providing two crossing points
of contact between adjacent, facing peaks 38, so
that the area of the fill sheets 16-22 available for
cooling zones 28 is not unduly diminished. The
spacing of the sheets 16-22 is determined by the
configuration of the peaks 38 and associated valleys
40, and it has been found that the preferred, 30
inclination of the peaks 38 provides two points of
contact sufficient for the required stability of the
sheets 16-22 within a limited projected vertical
extent.
Furthermore, the corrugated sections 34,
36 function to evenly distribute water uniformly
across the top of the respective cooling zones 28
disposed therebelow. Along the top marginal edge
portions of each sheet 16-22, the upper sheet spac-
~o ing section 34 receives streams or droplets of water
dispersed from nozzle apparatus, apertures or other
types of distribution structure, and the water
disperses and forms a film on the surface of each
face of the corrugated section 34 for gravitational
flow downwardly thereacross with additional disper-
sion at each point of contact of adjacent peaks 38.
Upon reaching the lower extremities of the upper
corrugated section 34, the film continues to descend
toward associated regions of the cooling zone 28,
and as shown for example in Fig. 2 the face of the
fill sheets 16-22 is smoothly blended in areas
between the corrugated sections 34, 36 and the
cooling zone 28 therebelow in order to avoid unnec-
essary channeling of the film of water.
2~25i
1 Referring to Fig. 4, it can be appreclated
that the configuration of the peaks 38 is such as to
block the fall of substantially all of the water
that is dispersed from the overlyin~ spray appara-
tus. The water impacts the upper corrugated section
32 and is converted into films of water on the faces
of the sheets 16-22 to avoid free-fall passage of
the water through the space between the cooling
zones 28 until reaching the collection basin of the
tower therebelow, since otherwise such free-fall,
bypassing action of the water would adversely affect
the thermal performance of the fill assembly.
The upper corrugated spacing and water
dispersing section 34 also advantageously maintain
the top edge of respective sheets 16-22 in substan-
tially a straight, vertical reference plane so that
warpage of the top, free edge of each of the fillsheets is avoided. Moreover,~it has been found that
the corrugated section 3~ relieves a substantial
amount of sheet stress that would otherwise be
present in the interior thereof.
In similar fashion, the intermediate
corrugated section 36 relieves a substantial amount
of stress which would otherwise be present in the
associated fill sheet 16-22. In addition, the
intermediate corrugated section 36, besides func-
tioning to maintain the spacing between adjacent
fill sheets is operable to receive the film of water
descending from associated regions of the cooling
zone 28 thereabove and evenly distribute the same
along the length of the top edge of the adjacent,
underlying cooling zone 28.
Referring again to Fig. 1, an innermost,
side or marginal edge portion of adjacent fill
sheets 16, 18 of the outboard fill pack 12 is inte-
2~ii
1 grally formed at a location remote from the air
inlet louvers 24 to present a honeycomb structure 42
which is shown in more detail in Figs. 2-5. Simi-
larly, inner sides or marginal edge portions of
sheets 20, 22 of the outboard fill pack 12 are
constructed to present a honeycomb structure 44
complemental to and facing the honeycomb structure
42. soth of the honeycomb structures 42, 44 extend
along the entire vertical extent of the respective
fill packs 12, 14.
More specifically, and referring to Figs.
2 and 3, the marginal side edge portion of fill
sheet 16 comprises a first upright wall segment 46,
a first inclined wall segment 4S~ that depends from
wall segment 46, a second upright wall segment 50
laterally offset from segment 46, and a second
inclined wall segment 52 that depends from segment
50 in a direction opposite~to the direction of
inclination of wall segment 48.. In opposite fash-
ion, the marginal side edge portion of fill sheet 18
is formed to present upright, offset wall segments
54, 58 that are connected to oppositely inclined
wall segmen.ts 56, 60. The segments 46-52 continue
in a repeating pattern along the length of the edge
portion of fill sheet 16, while the segments 54-60
continue in a repeating cycle down the length of the
side portion of fill sheet 18.
When the fill pack 12 is assembled such
that the corrugated spacing sections 34, 36 are in
contact with each other, the upright wall segments
46 of fill sheet 16 engage upright wall segments 54
of fill sheet 18. At the same time, the upright
segments 58 of the fill sheet 18 contact upright
wall segments 50 of thè fill sheet 16. As a result,
the segments 46-60 combine to present a repeating,
l nested, staggered pattern of hexagons in vertical
section, thus yielding the honeycomb-type appear-
ance.
In preferred forms of the invention, the
wall segments 46, 58 of sheets 16, 18 respectively
are formed to present horizontally extending index-
ing units 62 having a generally conical configura-
tion. The units 62 are received within correspond-
ing, complementally configured recess defining walls
64 that are integrally formed as part of upright
wall segments 50, 54. The units 62 interlock with
the recess defining wall 64 when the packs 12, 14
are assembled in order to increase the rigidity of
the packs 12, 14 while retaining adjacent regions of
the sheets 16-22 in a desired position and orienta-
tion.
The wall segments 46-60 are blended into
adjacent regions of the cooling zones 28 (or, alter-
natively, the corrugated spacing sections 34 or 36)
by inclined wall portions such as portions 66, 68
which can best be appreciated by reference to Fig.
2. Thus, the adjacent ends of the ridges 30 and
grooves 32 of the adjacent cooling zone 28 directly
connect with respective areas of the inclined wall
portions 66, 68.
The honeycomb structure 42, 44 and par-
ticularly the wall segments 46-60 thereof function
to guide the currents of air which are flowing in a
generally horizontal direction through the fill
assembly 10. More particularly, the honeycomb
structure 42, 44 guides along a horizontal path and
with minimal pressure loss air that is exiting from
the outboard fill pack 12 and is entering the in-
board fill pack 14. In this regard, fill packs 12,
14 are often spaced a slight distance apart (such as
-17-
3L2~2~
l 0.25 inch) for ease of assembly and so that stresses
developed in one of the fill packs 12, 14 are not
transmitted to the other pack.
In addition to horizontally guidlng the
air from fill pack 12 to fill pack 14, the honeycomb
structures 42, 44 assure that the flow rate of air
discharged from the fill pack 12 and entering fill
pack 14 is substantially uniform across the entire
vertical extent of the assembly 10, so that a uni-
form supply of air is provided to all areas of the
cooling zones 28. ~lso, the upright wall segments
46, 50, 5g and 58 provide a means ~or retaining
adjacent fill sheets 16-22 a predetermined hori-
zontal distance apart from each other, so that the
space between adjacent areas of the cooling zones 28
is reliably maintained at a certain, preselected
dimension.
In this regard, th~ horizontal distance
between offset, upright wall segments 46, 50 and 54,
58 is substantially equal to the horizontal distance
between peaks 38 and valleys 40 of corrugated sec-
tions 34, 36 so that the honeycomb structures 42, 44
cooperate with the corrugated sections 34, 36 to
maintain the spacing between adjacent areas of the
cooling zones 28.
Finally, and again referring to Fig. 1,
the sheets 16-22 are formed with integral spacers 70
interspersed throughout the cooling zones 28. Also,
circular knockouts 72 which interrupt the serpentine
pattern of ridges 30 and grooves 32 may be removed
to receive tubular supports secured to opposite side
walls of the water cooling casing for mounting the
fill packs 12, 14 within the tower. soth the circu-
lar knockouts 72 and the spacers 70 may be of the
-18-
~L2~24;~5
l type described in more detail in the aforementioned
U.S. Patent No. 4,548,766.
The cooperative effect of the honeycomb
structures 42, 44, the corrugated sections 3~, 36 as
well as spacers 70, louvers 24 and eliminators 26 is
to maintain proper spacing around the entire peri~
meter of the fill sheets 16, 22 within practical
dimensions of the latter. In this manner, stresses
within the sheets 16, 22 are reduced and the likeli-
hood of warpage of the fill sheets 16-22 is largely
avoided. As a consequence, air which is drawn into
the assembly 10 encounters a uniform pressure drop
throughout all regions of the fill packs 12, 14 so
that uniform cooling of the descending water is
assured and channeling of both the air and water is
substantially eliminated.
~0
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