U.S. patent application number 12/844658 was filed with the patent office on 2011-09-22 for systems and methods for cooling computer data centers.
This patent application is currently assigned to MECHANICAL SERVICE & SYSTEMS, INC.. Invention is credited to William Addison Gast, JR., Dan Russell Wells.
Application Number | 20110225997 12/844658 |
Document ID | / |
Family ID | 44646121 |
Filed Date | 2011-09-22 |
United States Patent
Application |
20110225997 |
Kind Code |
A1 |
Gast, JR.; William Addison ;
et al. |
September 22, 2011 |
SYSTEMS AND METHODS FOR COOLING COMPUTER DATA CENTERS
Abstract
A data center cooling system is provided to maintain data center
temperatures without introducing detrimental conditions into the
data center. The computer data center cooling system has a cooling
tower that controllably provides cooling water at a temperature in
a particular range. The cooling water is then pumped through a
series of filtration, treatment, monitoring and separation
subsystems to reliably clean the cooling water of particles and
treat the cooling water to reduce the harmful effects of corrosion
and scaling. Further control subsystems utilize PID loop
controllers to maintain the temperature to the air-handler unit
cooling coils to within one (1) degree Fahrenheit of a set point
that is determined by the computer data center air conditions. The
cooling system utilizes either a primary loop or a combination of
primary/secondary loops to achieve the highest system
efficiency.
Inventors: |
Gast, JR.; William Addison;
(Lehi, UT) ; Wells; Dan Russell; (Riverton,
UT) |
Assignee: |
MECHANICAL SERVICE & SYSTEMS,
INC.
Midvale
UT
|
Family ID: |
44646121 |
Appl. No.: |
12/844658 |
Filed: |
July 27, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61314879 |
Mar 17, 2010 |
|
|
|
Current U.S.
Class: |
62/121 ;
62/171 |
Current CPC
Class: |
F28F 27/003 20130101;
H05K 7/20745 20130101; G06F 1/20 20130101; H05K 7/20836
20130101 |
Class at
Publication: |
62/121 ;
62/171 |
International
Class: |
F28C 1/00 20060101
F28C001/00; F28D 5/00 20060101 F28D005/00 |
Claims
1. An open-loop cooling system that provides cooling water for use
in cooling environmentally sensitive volumes of air, the open-loop
cooling system comprising: an evaporative heat exchanger that mixes
cooling water with air having a low wet bulb temperature to cool
the cooling water; a temperature control subsystem, connected to
the evaporative heat exchanger, that controls the temperature of
the cooling water circulating in the open-loop cooling system, the
temperature control subsystem comprising: a temperature monitor
that measures the temperature of the cooling water exiting the
evaporative heat exchanger; and a mechanical cooler that provides
supplementary mechanical cooling to the cooling water if the
temperature monitor indicates the temperature of the cooling water
is higher than a desired cooling temperature; and at least one
air-handler unit that facilitates the transfer of heat from the
environmentally sensitive volume of air to the cooling water.
2. The open-loop cooling system recited in claim 1, wherein the
environmentally sensitive volume is a data center.
3. The open-loop cooling system recited in claim 1, wherein the
evaporative heat exchanger is a cooling tower.
4. The open-loop cooling system recited in claim 1, wherein the
mechanical cooler comprises: a chiller, that provides the
supplementary mechanical cooling to the cooling water; and a
condenser, wherein the condenser is configured to use cooling water
exiting the evaporative heat exchanger as inlet water to cool the
mechanical cooler condenser, thereby utilizing the cooling
occurring in the evaporative heat exchanger.
5. The open-loop cooling system recited in claim 1, wherein the
desired cooling temperature of the cooling water is determined by
the wet bulb temperature of air in the data center.
6. The open-loop cooling system recited in claim 1, further
comprising a chemical treatment and monitoring subsystem.
7. The open-loop cooling system recited in claim 3, wherein the air
utilized in the cooling tower is atmospheric air with a low wet
bulb temperature.
8. The open-loop cooling system recited in claim 7, wherein
following the cooling of the cooling water, the atmospheric air is
exhausted to an ambient atmosphere, thereby using the ambient
atmosphere as a heat sink of the open-loop cooling system.
9. The open-loop cooling system recited in claim 1, further
comprising a mixing element that heats the cooling water if the
temperature control subsystem indicates the temperature of the
cooling water is cooler than the desired cooling temperature.
10. The open-loop cooling system recited in claim 9, wherein the
mixing element is a three-way valve that mixes warmer cooling water
returning from the air-handler with cooler cooling water from the
cooling tower.
11. The open-loop cooling system recited in claim 1, further
comprising an air removal subsystem having a piping configuration,
wherein the air-handler supply piping stems from a bottom or a side
of a system pump outlet piping section, such that air is not
directed to the air-handler unit.
12. An open-loop cooling system for use in cooling a data center,
comprising: at least one air-handler unit configured to facilitate
the transfer of heat from air in the data center to cooling water
that circulates through a cooling water system, the cooling water
system comprising: a cooling tower connected to the air-handler
unit, wherein the cooling tower allows cooling water to mix with
air having a low wet bulb temperature; and a temperature control
subsystem, connected to the cooling tower and the air-handler unit,
that controls the temperature of the cooling water circulating in
the cooling water system, the temperature control subsystem
comprising: a temperature monitor that measures the temperature of
the cooling water exiting the cooling tower; a mechanical cooler
that provides supplementary mechanical cooling to the cooling water
if the temperature control subsystem indicates the temperature of
the cooling water is higher than the desired cooling temperature;
and a mixing element that heats the cooling water if the
temperature control subsystem indicates the temperature of the
cooling water is cooler than the desired cooling temperature.
13. The open-loop cooling system recited in claim 11, wherein the
desired cooling temperature of the cooling water is determined by
the wet bulb temperature of air in the data center.
14. The open-loop cooling system recited in claim 11, further
comprising a chemical treatment and monitoring subsystem.
15. The open-loop cooling system recited in claim 11, wherein the
air utilized in the cooling tower is atmospheric air with a low wet
bulb temperature.
16. The open-loop cooling system recited in claim 12, wherein
following the cooling of the cooling water, the atmospheric air is
exhausted to an ambient atmosphere, thereby using the ambient
atmosphere as a heat sink of the open-loop cooling system.
17. A method for data center cooling using an open-loop evaporative
system that facilitates the production of cooling water at a
desired cooling temperature, the method comprising: mixing heated
cooling water with air having a low wet bulb temperature in a
cooling tower, thereby utilizing the latent heat of vaporization to
cool the cooling water; circulating at least a portion of the
cooling water through a temperature control subsystem, wherein the
temperature control subsystem measures the temperature of the
cooling water; comparing the temperature measured in the
temperature control subsystem to the desired cooling water
temperature; altering the temperature of the cooling water in the
temperature control subsystem if the cooling water temperature is
different from the desired cooling temperature; circulating the
cooling water through one or more cooling coils of an air-handler
unit, wherein air from the data center is forced across the cooling
coil such that the air from the data center transfers its heat to
the cooling water; and returning the heated cooling water to the
cooling tower.
18. The method as recited in claim 17, further comprising
determining the desired temperature from the wet bulb temperature
of air in the data center.
19. The method as recited in claim 16, further comprising:
utilizing atmospheric air having a low wet bulb temperature in the
cooling tower; and exhausting the atmospheric air after cooling the
cooling water occurs back to the ambient atmosphere.
20. The method as recited in claim 19, further comprising
monitoring the chemical composition of the cooling water.
Description
BACKGROUND OF THE INVENTION
[0001] 1. The Field of the Invention
[0002] This invention relates to cooling systems that provide
cooling to computer data centers.
[0003] 2. Background and Relevant Art
[0004] Generally, modern computer data centers have servers,
switches, and networking equipment that are maintained to
environmental standards, such as those discussed in ASHRAE TC 9.9,
which is hereby incorporated by reference in its entirety. Data
centers use a significant amount of energy to operate, and in fact,
data center energy use is one of the fastest growing segments of
energy consumption in the United States. Experts predict that by
the year 2020, data center energy use will surpass the metals
industry as the largest segment of energy consumption in the United
States. This fact is driving data centers, especially large data
centers, to find and use more energy efficient methods and
systems.
[0005] One way in which data centers may become more energy
efficient is through increasing the efficiency of the cooling
systems used to cool the data center. Conventional cooling systems
may include a chiller, direct expansion gas cooling, water-side
economizer, air-side economizer, or some combination of these
components. In addition, conventional cooling systems often utilize
water or glycol as a cooling medium in closed loop systems.
Alternatively, conventional cooling systems may utilize computer
room air cooling (CRAC) units placed near the server racks in a
data center. In these systems, cooling is accomplished by direct
expansion, water-side economizer, or chilled water.
[0006] Conventional cooling systems typically use between 0.5 and
1.8 kilowatts per ton of cooling produced. As an example, a
conventional large collocation facility may use 400 tons of
cooling, and therefore, a data center cooling system that decreases
this load would significantly reduce overall energy costs.
[0007] Efforts directed at energy efficient cooling systems have
focused on efficient air or other fluid distribution. For example,
there have been inventions directed towards increasing the
efficiency of chillers (US Pub. 20030067745), air distribution (US
Pub. 20090168345, US Publ. 20040206101, U.S. Pat. No. 7,112,131,
U.S. Pat. No. 6,859,366), hot and cold aisle isolation (US Pub.
20080185446), using outside air (US Pub. 20090210096), and even
locating data centers on barges and using seawater to cool them (US
Pub. 20080209234).
BRIEF SUMMARY OF THE INVENTION
[0008] Embodiments of the present invention include systems,
devices and methods used to increase the energy efficiency of data
center cooling systems. In particular, example embodiments of the
present invention include an indirect open-loop evaporative cooling
system that provides cooling to data centers. By using a unique
open-loop system, higher energy efficiencies are obtained because
the system cooling water is exposed to ambient air with a low wet
bulb temperature. This exposure allows the cooling water to utilize
the energy transfer involved in vaporization to cool the cooling
water to within approximately three to five degrees Fahrenheit of
the dew point. The system therefore, uses the dry ambient air as
the ultimate thermal sink of the system.
[0009] In this way, embodiments of the present invention can
provide cooling systems that produce cooled water at an energy cost
ranging from approximately 0.05 to 0.15 kilowatts per ton. At this
rate, in a 400-ton conventional large collocation facility, the
energy savings would be between approximately 2 and 6 gigawatt
hours per year.
[0010] Example embodiments of the present invention are
advantageous because they provide a significant increase in the
operating efficiency compared to conventional data center cooling
systems. For example, the use of an open-loop system gains
efficiencies in power consumption and water usage. The electrical
power is saved through the increases in cooling efficiency, and
water consumption is reduced by the elimination of the need to
reject large amounts of heat generated by mechanical cooling
devices, such as chillers.
[0011] In a preferred configuration of the invention, an open-loop
cooling system that provides cooling water of a desired cooling
temperature is used for cooling environmentally sensitive volumes
of air. This system includes an evaporative heat exchanger. Within
the evaporative heat exchanger, cooling water is cooled by mixing
the cooling water with air that has a low wet bulb temperature.
[0012] Also, the system includes a temperature control subsystem
which is connected to the evaporative heat exchanger and controls
the temperature of the cooling water circulating in the open-loop
cooling system. The temperature control subsystem includes a
temperature monitor that measures the temperature of the cooling
water. The subsystem also includes a mechanical cooler that
provides supplementary mechanical cooling to the cooling water when
the temperature control subsystem indicates the temperature of the
cooling water is hotter than the desired cooling temperature. The
subsystem also includes a mixing element that heats the cooling
water if the temperature control subsystem indicates the
temperature of the cooling water is cooler than the desired cooling
temperature.
[0013] The open-loop cooling system also includes at least one
air-handler unit, which is connected to the evaporative heat
exchanger and the temperature control subsystem. The air-handler
unit facilitates the transfer of heat from the environmentally
sensitive volume of air to the cooling water.
[0014] According to another configuration of the invention, an
open-loop cooling system used in cooling a data center includes at
least one air-handler unit. The air-handler unit is configured to
facilitate the transfer of heat from air in the data center to
cooling water that circulates through a cooling water system. The
cooling water system provides cooling water at a desired cooling
temperature.
[0015] The cooling water system includes a cooling tower, which is
connected to the air-handler unit. Within the cooling tower, the
cooling water mixes with air that has a low wet bulb temperature.
The mixing cools the cooling water.
[0016] The cooling water system also includes a temperature control
subsystem, which is connected to the cooling tower and the
air-handler unit. The temperature control subsystem controls the
temperature of the cooling water circulating in the cooling water
system. The subsystem includes a temperature monitor that measures
the temperature of the cooling water. The subsystem also includes a
mechanical cooler that provides supplementary mechanical cooling to
the cooling water if the temperature control subsystem indicates
the temperature of the cooling water is hotter than the desired
cooling temperature. The subsystem also includes a mixing element
that heats the cooling water if the temperature control subsystem
indicates the temperature of the cooling water is cooler than the
desired cooling temperature.
[0017] The invention extends to a method for data center cooling
using an open-loop evaporative system that facilitates the
production of cooling water at a desired cooling temperature. The
method includes the step of mixing heated cooling water with air
that has a low wet bulb temperature in a cooling tower. This step
utilizes the latent heat of vaporization to cool the cooling water.
The cooling water circulates through one or more cooling coils of
an air-handler unit. Within the air-handler unit, the air from the
data center is forced across the cooling coil such that the air
transfers its heat to the cooling water. This step heats the
cooling water, which returns to the evaporative cooling tower.
[0018] Additional features and advantages of embodiments of the
present invention will be set forth in the description that
follows, and in part will be obvious from the description, or may
be learned by the practice of such exemplary embodiments. The
features and advantages of such embodiments may be realized and
obtained by means of the instruments and combinations particularly
pointed out in the appended claims. These and other features will
become more fully apparent from the following description and
appended claims, or may be learned by the practice of such
exemplary embodiments as set forth hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to describe the manner in which the above-recited
and other advantages and features of the invention can be obtained,
a more particular description of the invention briefly described
above will be rendered by reference to specific embodiments thereof
which are illustrated in the appended drawings. Understanding that
these drawings depict only typical embodiments of the invention and
are not therefore to be considered to be limiting of its scope, the
invention will be described and explained with additional
specificity and detail through the use of the accompanying drawings
in which:
[0020] FIG. 1 illustrates a block diagram of an example of the data
center cooling system;
[0021] FIG. 2 illustrates a piping diagram of an example of the
data center cooling system;
[0022] FIG. 3 illustrates a psychometric chart showing the cooling
process that can be accomplished by embodiments of the cooling
system;
[0023] FIG. 4 illustrates an embodiment of the air-handler
unit;
[0024] FIG. 5 illustrates air entrapment remedies used in an
embodiment of the cooling system; and
[0025] FIG. 6 illustrates a system that may be used for freeze
protection in standby pumps.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] Embodiments of the present invention include systems,
devices and methods used to increase the energy efficiency of data
center cooling systems, e.g., computer data centers. In particular,
example embodiments of the present invention include an indirect
open-loop evaporative cooling system that provides cooling to data
centers. By using a unique open-loop system, higher energy
efficiencies are obtained because the system cooling water is
exposed to ambient air with a low wet bulb temperature. This
exposure allows the cooling water to utilize the energy transfer
involved in vaporization to cool the cooling water to within
approximately three to five degrees Fahrenheit of the dew point.
The system therefore, uses the dry ambient air as the ultimate
thermal sink of the system.
[0027] As an overview, FIG. 1 shows an example of an open-loop
cooling system 50 according to one embodiment of the present
invention. For example, FIG. 1 illustrates that the open-loop
cooling system 50 can include a cooling tower 100, one or more
tower pumps 101, one or more system pumps 106, a filtration
subsystem 102, a chemical treatment and monitoring subsystem 103, a
temperature control subsystem 104, one or more air-handler units
105, a computer data center 140, data center air 145, and cooling
water 55 that circulates through the open-loop cooling system
50.
[0028] Generally, the open-loop cooling system 50 can include
piping sections through which the cooling water 55 circulates and
which connect components making up the open-loop cooling system 50.
For example, in the embodiment illustrated in FIG. 1, the cooling
water 55 circulates through a cooling tower outlet piping section
116, a tower pump inlet piping section 117, a tower pump outlet
piping section 136, a chemical treatment inlet piping section 118,
a chemical treatment outlet piping section 119, a filter inlet
piping section 120, a filter outlet piping section 121, a
mechanical cooling inlet piping section 122, a mechanical cooling
outlet piping section 123, a mixing element inlet piping section
128, a mixing element outlet piping section 129, a mixing element
cross-over piping section 130, a system pump inlet piping section
131, a system pump outlet piping section 132, an air-handler inlet
piping section 133, and a system return piping section 135. In
alternate embodiments, the configuration of the piping sections as
well as the inclusion of various sections may vary from one
embodiment to the next depending the cooling requirements of the
data center 140.
[0029] Notwithstanding the various piping sections configurations,
FIG. 1 illustrates that the open-loop cooling system 50 includes
cooling tower 100. In one example embodiment, cooling tower 100 has
a high efficiency counter-flow design with an induced draft fan. In
alternate embodiments, the cooling tower may utilize other designs
and configurations that perform the same or similar function as
will be described below.
[0030] In particular, the cooling tower 100 uses the induced draft
fan to draw or blow atmospheric air 51 through an atmospheric air
inlet 107. The atmospheric air 51 interacts with the cooling water
55 that exits the system return piping section 135 and enters the
cooling tower 100. As the cooling water 55 exiting the return
piping section 135 mixes with the atmospheric air 51, the latent
heat of vaporization is absorbed from the cooling water 55 and the
atmospheric air 51. As a result, the cooling water 55 is
cooled.
[0031] The rate and amount of cooling performed within the cooling
tower 100 may depend on the wet bulb characteristics of the
atmospheric air 51. Generally, the lower the wet bulb temperature
of the atmospheric air 51, the more cooling that takes place within
the cooling tower 100. Thus, the open-loop cooling system 50 can be
installed in geographic locations known to have atmospheric air 51
with low wet bulb temperatures, such as deserts or arid climates.
In these optimal climates, the cooling tower 100, may cool the
cooling water 55 to within three to five degrees Fahrenheit of the
dew point. Aside from the optimal climates, the open-loop cooling
system 50 can be installed in a wide-range of geographic locations,
although the exact efficiencies of the open-loop cooling system 50
may vary with atmospheric characteristics.
[0032] Returning to the open-loop cooling system 50, after the
atmospheric air 51 is cooled within the cooling tower 100, the
atmospheric air 51 is exhausted to the atmosphere through an
atmospheric air exhaust 110. For example, FIG. 1 illustrates that
the cooling tower 100 includes an atmospheric air exhaust 110. In
one example embodiment, the atmospheric air exhaust 110 is located
opposite of the atmospheric air inlet 107 to form a defined flow
path of the atmospheric air 51 through the cooling tower 100. In
alternate embodiments, the location of the atmospheric air exhaust
110 can vary.
[0033] Just as the atmospheric air 51 exhausts from the cooling
tower 100, the cooling water 55 which has been cooled also exits
the cooling tower 100. In one example embodiment, the cooling tower
100 is connected to the tower pumps 101 via the tower outlet piping
section 116. In particular, after the cooling water 55 is cooled
within the cooling tower 100, the cooling water 55 accumulates
within the cooling tower 100 and the tower pumps 101 pump the
cooling water 55 through the tower outlet piping section 116, into
the tower pump inlet piping section 117, and through the tower
pumps 101.
[0034] Although one or more tower pumps 101 can be employed in
various configurations, FIG. 2 illustrates one example embodiment
in which the tower pumps 101a and 101b are configured in parallel.
In the parallel configuration, one of tower pumps is designated as
the operating tower pump 101a, while the other tower pump is
designated as the standby tower pump 101b. Thus, the operating
tower pump 101a normally pumps the cooling water 55, while the
standby tower pump 101b remains in standby in case the operating
tower pump 101a fails or another system condition requires the use
of the standby tower pump 101b. In alternate embodiments, the tower
pumps 101 may be configured in series or a single pump may be
utilized.
[0035] The tower pumps 101 are used to circulate the cooling water
55 through various components and subsystems of the open-loop
cooling system 50. In one example embodiment, the tower pumps 101
are connected to the chemical treatment and monitoring subsystem
103 and the filtration subsystem 102 via the tower pump outlet
piping section 136. In particular, the tower pump outlet piping
section 136 can connect to the chemical treatment inlet piping
section 118 to circulate water through the chemical treatment and
monitoring subsystem 103. The chemical treatment outlet piping
section 119 is configured to return cooling water 55 that has been
chemically treated to the tower pump outlet piping section 136.
[0036] In one embodiment of the open loop cooling system 50, at
least a portion of the cooling water 55 may be routed through the
chemical treatment and monitoring subsystem 103. For example, in
the configuration illustrated in FIG. 1, a portion of the cooling
water 55 exiting the tower pumps 101 into the tower pump outlet
piping section 136 enters the chemical treatment and monitoring
subsystem 103 via the chemical treatment inlet piping section 118.
The remainder of the cooling water 55 exiting the tower pumps 101
remains in the tower pump outlet piping section 136 and proceeds to
the filter inlet piping section 120. In alternative embodiments,
none or all of the cooling water 55 exiting the tower pumps 101 may
enter the chemical treatment and monitoring subsystem 103.
[0037] The portion of cooling water that enters the chemical
treatment and monitoring subsystem 103 can be controlled by one or
more valves. The valves can be electronically controlled and
coupled with other devices, such as flow rate meters, to direct
substantially exact portions of the cooling water 55 to the
chemical treatment and monitoring subsystem 103 in order to
maintain consistent chemical properties in the cooling water
55.
[0038] Additionally, a dedicated chemical subsystem pump may
circulate the portion of cooling water 55 that enters the chemical
treatment and monitoring subsystem 103. For example in the
embodiment illustrated in FIG. 2, a dedicated chemical subsystem
pump 210 circulates the cooling water 55 through the chemical
treatment and monitoring subsystem 103. In alternate embodiments,
the open-loop cooling system 50 may utilize an alternate pressure
source to circulate the cooling water 55 through the chemical
treatment and monitoring subsystem 103.
[0039] In addition to the various components used to direct cooling
water 55 to the chemical treatment and monitoring subsystem 103,
the chemical treatment and monitoring subsystem 103 can include
various components to chemically monitor the cooling water 55 and
chemically treat the cooling water 55. For example, FIG. 2
illustrates that the chemical treatment and monitoring subsystem
103 can include a corrosion coupon rack 202. In operation, the
corrosion coupon rack 202 includes coupons of known size/weight of
a material that can corrode when exposed to the cooling water 55,
such as copper. In alternative embodiments, other corrodible
materials can be used within the corrosion coupon rack 202.
[0040] The coupons are positioned on the corrosion coupon rack 202
such that the coupons interface with the cooling water 55. The rate
at which the coupons corrode depends upon the corrosive properties
of the cooling water 55. The coupons can then be removed from the
corrosion coupon rack 202 and measured and/or weighed to determine
and monitor the corrosive properties of the cooling water 55. For
example, if the cooling water 55 becomes too corrosive, remedial
actions can be taken, such as adding additional chemicals to the
cooling water 55 to make the cooling water 55 less corrosive.
[0041] In one example embodiment, the chemical treatment and
monitoring subsystem 103 includes a chemical injection pump 204, as
illustrated in FIG. 2. The chemical injection pump 204 allows an
operator to inject chemicals as required into the open-loop cooling
system 50 via the chemical treatment and monitoring subsystem 103.
In one example, an operator can control the chemical injection pump
204 from a control center. In alternate embodiments, the chemical
treatment and monitoring subsystem 103 automatically injects
chemicals as required by the open-loop cooling system 50.
[0042] In addition to the chemical injection pump 204, the chemical
treatment and monitoring subsystem 103 may include additional
components. For example, FIG. 2 illustrates an embodiment of the
chemical treatment and monitoring subsystem 103 that includes a
centrifuge 203. The centrifuge 203 can separate particulate matter
contained in the cooling water 55 that is routed to the chemical
treatment and monitoring subsystem 103. In alternate embodiments,
the chemical treatment and monitoring subsystem 103 can include
similar components and processes that separate corrosive particular
matter from the cooling water 55.
[0043] In addition to the components described above, the chemical
treatment and monitoring subsystem 103 can include a wide array of
chemical monitoring equipment used to monitor a wide array of
chemical properties of the cooling water 55, depending on the
desired chemical properties of the cooling water 55. For example,
in one embodiment, the cooling water 55 is substantially pure
water. In alternative embodiments, however, the cooling water 55
can be chemically treated water, a water-based chemical solution,
or another cooling medium with carefully engineered thermodynamic
properties.
[0044] Once the cooling water 55 or a portion of cooling water 55
is processed through the chemical treatment and monitoring
subsystem 103, the cooling water 55 can enter the filtration
subsystem 102. For example, as shown in FIG. 1, the chemical
treatment and monitoring subsystem 103 is connected to the
filtration subsystem 102 via the chemical treatment outlet piping
section 119, and the filter inlet piping section 120. The cooling
water 55 exiting the chemical treatment and monitoring subsystem
103 via the chemical treatment outlet piping section 119 mixes with
the cooling water 55 that did not enter the chemical treatment and
monitoring subsystem 103 in the filter inlet piping section 120,
and then enters the filtration subsystem 102. In alternative
embodiments, the cooling water 55 exiting the chemical treatment
and monitoring subsystem 103 via the chemical treatment outlet
piping section 119 may mix with the cooling water 55 that did not
enter the chemical treatment and monitoring subsystem 103 at
another point in the open-loop cooling system 50.
[0045] The filtration subsystem 102 filters the cooling water 55
before it enters the filter outlet piping section 121. The
filtration subsystem 102 can include, but is not limited to media
filters, screen filters, disk filters, slow sand filter beds, rapid
sand filters and cloth filters that can be configured to various
sizes of particles from the cooling water 55. In at least one
embodiment, the filtration subsystem 102 substantially prevents a
particle of a predetermined size or larger from circulating with
the cooling water 55 through the portion of the open-loop cooling
system 50 behind the filtration subsystem 102.
[0046] Once the cooling water 55 passes through the filtration
subsystem 102, the cooling water 55 can enter one or more
subsystems within the open-loop cooling system 50. For example, as
shown in FIG. 1, the filtration subsystem 102 is connected to the
temperature control subsystem 104 via the filter outlet piping
section 121. In alternate embodiments, the connection between the
filtration subsystem 102 and the temperature control subsystem 104
can exist in an alternate location in the open-loop cooling system
50.
[0047] Generally, the temperature control subsystem 104 provides
the cooling water 55 with supplementary temperature control in the
event that the cooling tower 100 was unable to produce cooling
water 55 with a desired temperature for the cooling cycle. For
example, in the event that the atmospheric air 51 becomes humid,
the atmospheric air 51 will have a higher wet bulb temperature.
This condition reduces the efficiency of the cooling that occurs in
the cooling tower 100 and may necessitate supplementary mechanical
cooling in the temperature control subsystem 104.
[0048] Additionally, the temperature control subsystem 104 can be
configured to function only if the cooling water 55 is not at the
desired temperature. For example, if the cooling water 55 is at the
desired temperature, the cooling water 55 can bypass the
temperature control subsystem 104.
[0049] Depending on the temperature of the cooling water 55
entering the temperature control subsystem 104, the temperature
control subsystem 104 can employ various components to adjust the
temperature of the cooling water 55. In one example embodiment, the
temperature control subsystem 104 can include a mechanical cooler
137, such as a chiller, that can provide supplementary mechanical
cooling to the cooling water 55 as required to produce cooling
water 55 with the desired temperature for the cooling cycle.
[0050] Thus, the combination of the cooling tower 100 (high
efficient cooling) and the mechanical cooler 137 (lower efficient
cooling) used to control the temperature of the cooling water 55 is
highly energy efficient and may allow temperature control of the
cooling water 55 to within one (1) degree Fahrenheit. For example,
under certain conditions, the atmospheric air 51 has wet bulb
temperature properties that allow the cooling tower 100 to
adequately cool the cooling water 55, thus providing the highest
efficiency possible as no supplementary mechanical cooling is
needed. With other conditions, for example when the atmospheric air
51 has a higher wet bulb temperature, the cooling water 55 can
require supplementary mechanical cooling. However, because the
cooling tower 100 has provided most of the cooling, the mechanical
cooler 137 only needs to lower the temperature of the cooling water
55 a few degrees. Thus, the majority of the work performed in the
open loop cooling system 50 is provided by the high efficient
cooling component while the lower efficient cooling is only
utilized as required and in a limited fashion. Therefore, the
temperature of the cooling water 55 is controlled in a highly
energy efficient manner.
[0051] In addition, FIG. 1 illustrates that the temperature control
subsystem 104 can be configured in series with the cooling tower
100. Configuring the temperature control subsystem 104 in series
with the cooling tower 100 eliminates the need for an additional
cooling tower, heat exchangers, or secondary closed loop for
chilled water or glycol, as with conventional systems.
[0052] As shown in FIG. 1, the mechanical cooler 137 is connected
to the filter outlet piping section 121 via the mechanical cooling
inlet piping section 122 and the mechanical cooling outlet piping
section 123. A controlled portion of the cooling water 55 exiting
the filtration subsystem 102 through the filter outlet piping
section 121 enters the mechanical cooling inlet piping section 122.
The remainder of the cooling water 55 remains in the filter outlet
piping section 121. Depending on the wet bulb temperature of the
data center air 145, the amount of cooling water 55 that enters the
mechanical cooler 137 can range from none of the cooling water 55
to all of the cooling water 55.
[0053] In alternative embodiments, the portion of the cooling water
55 entering the mechanical cooler 137 could be based on other
physical conditions in the open-loop cooling system 50. For
example, the portion of the cooling water that enters the
mechanical cooler 137 from the filter outlet piping section 121 may
be controlled such that condensation does not form in the
air-handler units 105.
[0054] In addition, in the embodiment illustrated in FIG. 1, the
cooling water 55 that entered the mechanical cooler 137 via the
mechanical cooling inlet piping section 122 is cooled in the
mechanical cooler 137 then exits the mechanical cooler 137 via the
mechanical cooling outlet piping section 123. The cooling water 55
exiting the mechanical cooler 137 via the mechanical cooling outlet
piping section 123 mixes with the portion of the cooling water 55
that exited the filtration subsystem 102 via the filter outlet
piping section 121. The result of the mixing of the cooling water
55 exiting the mechanical cooler 137 via the mechanical cooling
outlet piping section 123 with the cooling water 55 exiting the
filtration subsystem 102 via the filter outlet piping section 121
is the cooling water 55 in the mixing element inlet piping section
128 is cooler than the cooling water 55 exiting the filtration
subsystem 102.
[0055] In one example embodiment of the temperature control
subsystem 104, twenty-five percent of the cooling water 55 exiting
the filtration subsystem 102 via the filter outlet piping section
121 enters the mechanical cooler 137 via the mechanical cooling
inlet piping section 122. In this example embodiment, the cooling
water 55 is cooled twenty degrees Fahrenheit in the mechanical
cooler 137. The cooling water 55 then exits the mechanical cooler
137 via the mechanical cooling outlet piping section 123. The
cooling water 55 exiting the mechanical cooler 137 via the
mechanical cooling outlet piping section 123 mixes with the cooling
water 55 that exited the filtration subsystem 102 via the filter
outlet piping section 121 and entered the mixing element inlet
piping section 128. When this mixing occurs, the cooling water 55
entering the mixing element inlet piping section 128 is cooled five
degrees Fahrenheit.
[0056] If a ten degree Fahrenheit cooling was needed, fifty percent
of the cooling water 55 can be directed into the mechanical cooler
137 to be cooled by twenty degrees. Thus, when the fifty percent
portion is mixed with the cooling water 55 that was not
mechanically cooled, the overall temperature drop of the cooling
water 55 would be ten degrees.
[0057] FIG. 2 illustrates another example of a mechanical cooler.
In particular, FIG. 2 illustrates a temperature control subsystem
104 that includes a multi-element mechanical cooler 221 consisting
of a condenser 223 and a chiller 222. In the embodiment illustrated
in FIG. 2, the condenser 223 is connected to the filter outlet
piping section 121 via a condenser cooling inlet piping section
126. The condenser 223 is connected to system return piping section
135 via a condenser cooling outlet piping section 127.
[0058] In the embodiment illustrated in FIG. 2, a portion of the
cooling water 55 exiting the filtration subsystem 102 enters the
condenser 223 via the condenser cooling inlet piping section 126.
The condenser 223 utilizes the cooling water 55 as the cooling
medium for the chiller 222. The cooling water 55 utilized in the
condenser 223 as a cooling medium exits the condenser 223 via the
condenser cooling outlet piping section 127 and is routed to the
system return piping section 135. Thus, the configuration
illustrated in FIG. 2 utilizes the cooling capacity of the cooling
tower 100 to a maximum extent as well as prevents the heat absorbed
in the condenser 223 from being introduced into the open-loop
cooling system 50.
[0059] In some atmospheric conditions, it may be the case that the
cooling tower 100 cooled the cooling water 55 to a temperature
below the desired temperature of the cooling cycle. Under these
conditions, the cooling water 55 needs to be heated to provide the
required cooling of the data center air 145 through the air-handler
units 105 (discussed further below). Thus, in one example
embodiment, the temperature control subsystem 104 can include a
mixing element 138 to increase the temperature of the cooling water
55 if the cooling water 55 is too cold, as illustrated in FIG.
1.
[0060] In one example embodiment, the mixing element 138 is a valve
that mixes cooling water 55 with a high temperature exiting the
air-handler units 105 with the cooling water 55 with a low
temperature in the temperature control subsystem 104. For example,
FIG. 2 illustrates a mixing element 138 that is a three-way bypass
valve 220. In alternate embodiments, the mixing element 138 may be
an injection pump. The mixing element 138 can be communicably
connected to a control center that automatically controls the
mixing element 138 based on the temperature of the cooling water 55
entering the temperature control subsystem 104.
[0061] As shown in FIG. 1, the mixing element 138 is connected to
the mechanical cooler 137 and the filtration subsystem 102 via the
mixing element inlet piping section 128 which is connected to the
filter outlet piping section 121 and the mechanical cooling outlet
piping section 123. As further illustrated in FIG. 1, the mixing
element 138 is connected to the system return piping section 135
via the mixing element cross-over piping section 130. As further
illustrated in FIG. 1, the mixing element 138 is connected to the
system pump inlet piping section 131 via the mixing element outlet
piping 129.
[0062] Furthermore, FIG. 1 illustrates that the mixing element 138
mixes the cooling water 55 entering the mixing element 138 via the
mixing element inlet piping section 128 with the cooling water 55
in the system return piping section 135 via the mixing element
cross-over piping 130 then routes the cooling water 55 that has
been mixed to the mixing element outlet piping section 129. By
mixing the cooling water 55 entering the mixing element 138 via the
mixing element inlet piping section 128 with the cooling water 55
entering the mixing element 138 via the mixing element cross-over
piping section 130 from the in the system return piping section
135, the mixing element 138 increases the temperature of the
cooling water 55 exiting the mixing element 138 into the mixing
element outlet piping section 129.
[0063] In addition, in the example embodiment illustrated in FIG.
1, the quantity of cooling water 55 entering the mixing element 138
via the mixing element cross-over piping section 130 from the
system return piping section 135 may be determined by the wet bulb
temperature of the data center air 145. In alternate embodiments,
the quantity of cooling water 55 entering the mixing element 138 is
determined by other physical properties of the open-loop cooling
system 50. For example, the quantity of the cooling water 55
entering the mixing element 138 via the mixing element cross-over
piping section 130 from the system return piping section 135 is
determined such that condensation does not form in the one or more
air-handler units 105.
[0064] In addition, in an embodiment of the invention, the
temperature control subsystem 104 may use a dedicated condenser
pump and a dedicated chiller pump. For example, in the embodiment
illustrated in FIG. 2, the temperature control subsystem 104
includes a dedicated condenser pump 212 and a dedicated chiller
pump 211.
[0065] In this embodiment, an alternative piping configuration can
be utilized. For example, as illustrated in FIG. 2, the condenser
cooling inlet piping section 126 is connected to the filter outlet
piping section 121. The mechanical cooling inlet piping section 122
is connected to the mixing element outlet piping section 129 rather
than the filter outlet piping section 121 as illustrated in FIG. 1.
Additionally, in this embodiment, cooling water 55 exiting the
chiller 222 circulates into the system pump inlet piping section
131 rather than into the mixing element inlet piping section 128 as
illustrated in FIG. 1. In alternate embodiments, the piping
configuration between the temperature control subsystem 104 and the
open-loop cooling system 50 may take other configurations.
[0066] In the embodiment illustrated in FIG. 2, the dedicated
condenser pump 212 circulates cooling water 55 through the
condenser 223 via the condenser cooling inlet piping section 126.
The dedicated condenser pump 212 then circulates the cooling water
55 out of the condenser 223 into the system return piping section
135 via the condenser cooling outlet piping section 127.
[0067] As further illustrated in FIG. 2, the dedicated chiller pump
211 circulates cooling water 55 into the chiller 222 via the
mechanical cooling inlet piping section 122. The dedicated chiller
pump 211 then circulates the cooling water 55 out of the chiller
222 into the system pump inlet piping section 131 via the
mechanical cooling outlet piping section 123. In alternate
embodiments, the open-loop cooling system 50 may utilize
configurations without a dedicated condenser pump and/or a
dedicated chiller pump.
[0068] As discussed above, the cooling tower 100 is in series with
the temperature control subsystem 104. This allows the cooling
tower 100 and the temperature control subsystem 104 to cool the
cooling water 55 to within a zone of efficient cooling. For
example, FIG. 3 illustrates a zone of efficient cooling 301 for the
example embodiment illustrated in FIG. 1 at average atmospheric
conditions at approximately 4200 feet above sea level. In alternate
embodiments, the zone of efficient cooling would shift due to
atmospheric conditions.
[0069] The open-loop cooling system 50 would be most efficient
below a given atmospheric wet bulb temperature. For example, the
open-loop cooling system 50 illustrated in FIG. 1 may be most
efficient in areas of the world with a maximum atmospheric wet bulb
temperature of 70 degrees Fahrenheit. FIG. 3 illustrates the
psychometric properties below the maximum wet bulb temperature of
70 degrees Fahrenheit 302. This physical condition produces the
highest efficiencies in the cooling tower 100. In alternate
embodiments, the maximum atmospheric wet bulb temperature producing
the highest efficiencies may vary with the particular system
configuration, ambient atmospheric conditions, and elevation.
[0070] As the cooling water 55 circulates through the open-loop
cooling system 50 the cooling water 55 is subject to psychometric
changes. A psychometric change of cooling water 55 in a cooling
tower 100 includes an initial physical state, a final physical
state, and a change line illustrating the intermediate physical
states between the initial and final physical state. For example,
FIG. 3 illustrates a cooling tower psychometric change 303 of the
cooling water 55 in the cooling tower 100. The cooling tower
psychometric change 303, for example, includes an initial physical
state 304, a final physical state 305, and a change line 306.
[0071] The cooling tower psychometric change 303 represents the
psychometric changes of the cooling water 55 as the cooling water
55 circulates from the system return piping section 135 through the
cooling tower 100 and into the cooling tower outlet piping section
116. The initial physical state 304 represents the physical
properties of the cooling water 55 in the system return piping
section 135. The final physical state 305 represents the physical
properties of the cooling water 55 in the cooling tower outlet
piping section 116. The change line 306 represents the cooling
occurring in the cooling tower 100 due to the mixing of the cooling
water 55 with the atmospheric air 51 with a low wet bulb
temperature. In alternate embodiments, the cooling tower
psychometric change 303 will vary with physical properties of the
system and the ambient conditions of the atmospheric air 51.
[0072] As illustrated in FIG. 3, the final physical state 305 is
located in the zone of efficient cooling 301. This illustrates that
in the embodiment illustrated in FIG. 1 during the cooling tower
psychometric change 303 the cooling tower 100 normally has the
ability of to provide sufficient cooling to the cooling water 55
for circulation in the open-loop cooling system 50.
[0073] Alternatively, if adverse ambient conditions exist such as
atmospheric air 51 with a high wet bulb temperature, the cooling
tower 100 may produce a cooling tower psychometric change in which
the final physical state of the cooling water 55 is outside the
zone of efficient cooling 301. For example, FIG. 3 illustrates an
inadequate cooling tower psychometric change 303a. The inadequate
cooling tower psychometric change 303a includes the initial
physical state 304, an intermediate physical state 305a, and an
intermediate change line 306a.
[0074] The inadequate cooling tower psychometric change 303a
represents the psychometric changes of the cooling water 55 as the
cooling water 55 circulates from the system return piping section
135 through the cooling tower 100 and into the cooling tower outlet
piping section 116. The initial physical state 304 represents the
physical properties of the cooling water 55 in the system return
piping section 135. The intermediate physical state 305a represents
the physical properties of the cooling water 55 in the cooling
tower outlet piping section 116. The intermediate change line 306a
represents the cooling occurring in the cooling tower 100 due to
the mixing of the cooling water 55 and atmospheric air 51 with a
higher-than-optimal wet bulb temperature. In alternate embodiments,
the inadequate cooling tower psychometric change 303a will vary
with physical properties of the system and the ambient conditions
of the atmospheric air 51.
[0075] As illustrated in FIG. 3, the intermediate physical state
305a is located outside of the zone of efficient cooling 301. This
illustrates that in the embodiment illustrated in FIG. 1 during the
inadequate cooling tower psychometric change 303a when adverse
atmospheric conditions exist, the cooling tower 100 may be unable
to provide sufficient cooling to the cooling water 55 for
circulation in the open-loop cooling system 50.
[0076] In this situation, additional cooling may be necessary. For
example, FIG. 3 illustrates a mechanical cooler psychometric change
307 of the cooling water 55 in the mechanical cooler 137. In this
situation, the open-loop cooling system 50 embodied in FIG. 1
introduces the cooling water 55 into a mechanical cooler 137.
Within the mechanical cooler 137, the cooling water 55 undergoes
psychometric changes. For example, FIG. 3 illustrates a mechanical
cooler psychometric change 307 of the cooling water 55 in the
mechanical cooler 137.
[0077] As with the cooling tower psychometric change 303, the
mechanical cooler psychometric change 307 can include an initial
psychometric state, a final psychometric state, and a trend line
illustrating the intermediate psychometric states between the
initial and final psychometric states. For example, in FIG. 3, the
mechanical cooling psychometric change 307 includes an initial
psychometric state 308 (which may coincide with intermediate
physical state 305a), a final psychometric state 310, and a trend
line 309.
[0078] The mechanical cooler psychometric change 307 represents the
psychometric changes of the cooling water 55 as the cooling water
55 circulates from the filter outlet piping section 121 through the
mechanical cooler 137 and into the mixing element inlet piping
section 128. The initial psychometric state 308 represents the
physical properties of the cooling water 55 in the filter outlet
piping section 121. The final psychometric state 310 represents the
physical properties of the cooling water 55 in the mixing element
inlet piping section 128. The trend line 309 represents the cooling
occurring due to the mechanical cooler 137. In alternate
embodiments, the mechanical cooler psychometric change 307 will
vary with physical properties of the mechanical cooler 137 and the
system configuration.
[0079] As illustrated in FIG. 3, the final psychometric state 310
is located within the zone of efficient cooling 301. Thus, the
cooling water 55 mechanically has been cooled from a physical state
outside the zone of efficient cooling 301, such as the intermediate
physical state 305a that resulted from the inadequate cooling tower
psychometric change 303a, to be within the zone of efficient
cooling 301. This illustrates that during the mechanical cooling
psychometric change 307 the mechanical cooler 137 has the ability
to provide supplemental mechanical cooling to the cooling water 55
for circulation in the open-loop cooling system 50.
[0080] Returning to FIG. 1, the remaining components of the
open-loop cooling system 50 will be described. As shown in FIG. 1,
the mixing element 138 is connected to the one or more system pumps
106 via the mixing element outlet piping section 129 and the system
pump inlet piping section 131. In the example embodiment
illustrated in FIG. 1, after the cooling water 55 exits the mixing
element 138 via the mixing element outlet piping section 129, the
one or more system pumps 106 pump the cooling water 55 in through
the system pump inlet piping section 131, out through the system
pump outlet piping section 132, and into the air-handler inlet
piping section 133. In alternate embodiments, the particular
configuration of these components may vary.
[0081] In addition to the system pumps 106 pumping the cooling
water exiting the mixing element 138, the system pumps 106 can have
various configurations. For example, in the embodiment illustrated
in FIG. 2, the system pumps 106a and 106b are configured in
parallel. In this configuration, one of system pumps is designated
as the operating system pump 106a, and the other system pump is
designated as the standby system pump 106b. That is, the operating
system pump 106a pumps the cooling water 55 while the standby
system pump 106b remains in standby. In alternate embodiments, the
system pumps 106 may be configured in series or a single pump may
be utilized.
[0082] As shown in FIG. 1, the one or more system pumps 106 are
connected to the one or more air-handler units 105 via the system
pump outlet piping section 132 and the air-handler inlet piping
section 133. As further shown in FIG. 1, the air-handler units 105
are connected to the cooling tower 100 via the system return piping
section 135.
[0083] Generally, the air-handler units 105 provide an interface
between the cooling water 55 cooled by the open-loop cooling system
50 and data center air 145 that has been heated in the computer
data center 140. For example, FIG. 1 illustrates that the data
center air 145 is moved into the air-handler units 105 though
ducting. Specifically, FIG. 1 illustrates the air-handler units 105
connected to the computer data center 140 via inlet ducting 141 and
outlet ducting 142.
[0084] Because the cooling water 55 entering the air-handler units
105 via the air-handler inlet piping section 133, is cooler than
the data center air 145 entering the air-handler units 105 via the
inlet ducting 141, the heat in the data center air 145 transfers to
the cooling water 55, thus cooling the data center air 145. The
data center air 145 having been cooled, returns to the computer
data center 140 via the outlet ducting 142, while the cooling water
55 which has been heated enters the system return piping section
135 to be directed to the cooling tower 100 to begin the cooling
cycle as described above.
[0085] In one example embodiment of the air-handler units 105, the
air-handler units 105 contain a cooling coil 401. For example, FIG.
4 illustrates an air-handler unit 105 containing a cooling coil
401. In the embodiment illustrated in FIG. 4, the air-handler inlet
piping section 133 connects to the cooling coil 401. The system
pumps 106 pump the cooling water 55 into the cooling coil 401 via
the air-handler inlet piping section 133. The cooling water 55
circulates through the cooling coil 401 then exits the cooling coil
401 into the system return piping section 135.
[0086] In the example embodiment of the air-handler unit 105
illustrated in FIG. 4, the data center air 145 enters the
air-handler unit 105 via the inlet ducting 141 then moves across
the cooling coil 401. As the data center air 145 moves across the
cooling coil 401, the data center air 145 transfers heat to the
cooling water 55 moving through the cooling coil 401. The data
center air 145 exits the air-handler unit 105 through the outlet
ducting 142.
[0087] As shown in FIG. 1, the inlet ducting 141 may contain a
humidification element 143. In the embodiment illustrated in FIG.
1, the humidity of the data center air 145 may be controlled by the
humidification element 143. For example, if the humidity level
needs to be increased to maintain the correct data center
environment, the humidification element 143 may inject water into
the inlet ducting 141 as the data center air 145 enters the
air-handler units 105. In alternate embodiments, the humidity of
the data center air 145 could be controlled through use of an
evaporative media section, or directly in the data center 140.
[0088] In an example embodiment of the open-loop cooling system 50,
an air removal subsystem 500 may be included to remove atmospheric
air 51 from the cooling water 55. For example, FIG. 5 illustrates
an example of an air removal subsystem 500 that may be included in
an embodiment of the open loop cooling system 50 to remove
atmospheric air 51 from the cooling water 55. In the embodiment
illustrated in FIG. 5, the air removal subsystem 500 includes a
supply piping port 502, a vent piping section 504, and a return
piping port 505.
[0089] As shown in FIG. 5, the supply piping port 502 is provided
on the top of the air-handler inlet piping section 133. The return
piping port 505 is provided on the top of the system return piping
section 135. The supply piping port 502 is connected via the vent
piping section 504 to the return piping port 505. In alternate
embodiments, the supply piping port 502 may be located on a
different section or multiple piping sections of the open-loop
cooling system 50.
[0090] In addition, in the embodiment illustrated in FIG. 5, the
air removal subsystem 500 may function due to a differential
pressure between the air-handler inlet piping section 133 and the
system return piping section 135. The differential pressure forces
atmospheric air 51 in the air-handler inlet piping section 133
through the supply piping port 502, through vent piping section
504, and through the return piping port 505. The atmospheric air 51
is mixed with the cooling water 55 in the system return piping
section 135 and is directed back to the cooling tower 100. The air
removal subsystem 500 illustrated in FIG. 5 can be located at a
high point of the open-loop cooling system 50. In alternate
embodiments, multiple air removal subsystems 500 may be located
throughout the system.
[0091] In an example embodiment of the open-loop cooling system 50,
air prevention subsystems 510 and 510a may be included to prevent
air from entering the air-handler units 105. For example, FIG. 5
illustrates examples of air prevention subsystems 510 and 510a that
may be included in an embodiment of the open loop cooling system to
prevent atmospheric air 51 remaining in the cooling water 55 from
entering the air-handler units 105.
[0092] As illustrated in FIG. 5, the air prevention subsystems 510
and 510a include the air-handler inlet piping section 133 connected
to the system pump outlet piping section 132 at the bottom
(illustrated in 510) or the side (illustrated in 510a) of the
piping and a vent valve 511. In alternate embodiments, the specific
piping sections utilized to prevent air from entering the
air-handler units 105 may vary.
[0093] As illustrated in FIG. 5, the cooling water 55 is allowed to
exit the system pump outlet piping section 132 and enter the
air-handler inlet piping section 133 without the atmospheric air 51
entering the air-handler inlet piping section 133. Therefore, the
cooling water 55 enters the air-handler units 105 without the
atmospheric air 51. The atmospheric air 51 is vented via the vent
valve 511. In alternate embodiments, the air remaining may be
disposed of through other means known in the art.
[0094] In an example embodiment illustrated in FIG. 2 of the
open-loop cooling system 50, the system pumps 106a and 106b and the
tower pumps 101a and 101b are configured in parallel (as discussed
above, FIG. 2 specifically illustrates examples of the operating
tower pump 101a and standby tower pump 101b along with the
operating system pump 106a and the standby system pump 106b
configured in parallel) that may require a freeze protection
subsystem 600 to prevent damage if the parallel pumps are exposed
to temperatures below thirty-two degrees Fahrenheit. For example,
FIG. 6 illustrates an embodiment of a freeze protection subsystem
600. The freeze protection subsystem 600 includes a standby pump
602, a standby pump check valve 603, a freeze protection cross-over
piping section 606, a standby pump outlet piping section 607, an
operating pump 601, an operating pump outlet piping section 605,
and a temperature sensor 604.
[0095] The freeze protection subsystem 600 operates by forming a
hole in the disc of the standby pump check valve 603. This hole
allows a small amount of the cooling water 55 pumped by the
operating pump 601 to flow from the operating pump outlet piping
section 605, through the freeze protection cross-over piping
section 606, down the standby pump outlet piping section 607,
through the hole drilled in the disc of the standby pump check
valve 603, and into the standby pump 602.
[0096] In addition, the freeze protection subsystem 600 may include
a temperature sensor 604. The temperature sensor 604 measures the
temperature of the cooling water 55 backflowing through the standby
pump 602. If the temperature of the cooling water 55 backflowing
through the standby pump 602 is below a preset temperature, the
standby pump 602 becomes the operating pump 601 and the operating
pump 601 becomes the standby pump 602.
[0097] The present invention can be embodied in other specific
forms without departing from its spirit or essential
characteristics. Thus, the described embodiments are to be
considered in all respects only as illustrative and not
restrictive. The scope of the invention is, therefore, indicated by
the appended claims rather than by the foregoing description. All
changes that come within the meaning and range of equivalency of
the claims are to be embraced within their scope.
* * * * *