Note: Descriptions are shown in the official language in which they were submitted.
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REAL-TIME PASSIVE COOLING APPARATUS WITH OPTIONAL
INTEGRATED STORAGE
FIELD OF THE INVENTION
The disclosed apparatus is in the field of passive cooling using a vertical
two-phase closed thermosyphon (TPCT) to displace energy that is used for
cooling
devices located inside buildings.
BACKGROUND
Independent cooling devices located in buildings consume energy to
lower the temperature of an enclosed volume and often reject heat to the air
inside
the building. In some instances, the ambient temperature outside the building
is
colder than the enclosed volume temperature of the independent device. A
passive
cooling apparatus allows reducing building energy loads to enhance the cooling
of
devices inside buildings. By using the colder ambient air and the wind,
intermittent
renewable cooling is possible in real-time at temperatures approximately
between -
20oC to 30oC. A passive cooling apparatus can reduce greenhouse gases when the
building's cooling energy originates from fossil fuels.
Reducing building energy loads is particularly important for near-net
zero buildings. The disclosed apparatus reduces the need for on-site
electricity
generation for near net-zero buildings, while eliminating compressor noise for
extended periods. It is known that cooling loads for air-conditioning and
refrigeration
systems for residential and commercial buildings account for almost 10% of the
electricity usage in Canada (Office of Energy Efficiency, ISBN 989-1-100-17240-
8,
2011). Solar contribution of photovoltaic electricity is 6.5% to 21% of
building loads
depending on orientation (R. Companion, Energy & Buildings, 36(4), p. 321-328,
2004). This implies that the development of near net-zero buildings requires
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displacing energy loads. Moreover, solar assisted cooling absorption systems
contribute to net-zero building applications, but they compete for limited
facade space.
Their cost is considerable making the use of absorption chillers and solar
collectors
economically challenging (M. Tiago and A.C. Oliveira, Applied Energy, 86, p.
949-
957, 2009). As 70% of building facades in urban areas access less than 50% of
available solar irradiation, it becomes mathematically difficult to achieve
near net-zero
buildings. The percentage of buildings that can achieve net-zero through
energy
efficiency and onsite generation becomes even more difficult for multi-floor
buildings:
offsite generation and sprawl remain the main options. In Canada a 10,000 m2
supermarket will consume 1.9 GWhr of electricity for refrigeration a year
which could
be considerably reduced with the invention disclosed.
TPCT are well-known passive heat transfer devices with no moving
parts. They consist of a closed vertical or inclined pipe with a controlled
charge two-
phase fluid and non-condensable gases removed. An important commercial
application for TPCT is to re-freeze permafrost to stabilize foundations made
unstable
due to climate change effects in northern climates (Xu J. and Goering D.J.,
Cold
Regions Science and Technology, 53(3), p 283-297, 2008). For such application,
TPCT design and predictive models are relatively simple: a freezing cycle
occurs over
approximately a 6-month period, predictive accuracy is not important, and the
overall
heat transfer over a year is relatively minimal as the ground acts as an
insulator once
refrozen. Other applications of TPCT is to extract heat from a water reservoir
during
nighttime and use the water during the day to cool buildings with applications
for
seasonal and nocturnal cooling of buildings (Chotivisarut N. and Kiatsiriroat
T.,
International Journal of Energy Research, 33(12), p 1089-1098, 2009). In such
cases, the focus is on air conditioning and is not concerned with reducing the
energy
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consumed by cooling devices located inside buildings in real-time. In
contrast, the
real-time passive cooling apparatus disclosed herein for near net-zero
buildings
requires accurate predictive knowledge of the cross-correlation of temperature
and
wind conditions, the wind shear layer, and the cooling profile of building
cooling
devices.
TPCT have also been used in other applications which are not focused
on reducing cooling loads of buildings. By way of example, cooling engines in
vehicles
(Suzuki M. et al., JSME International Journal, 41(4), p 927-935, 1998) and the
charging and discharging of a thermal energy storage using a thermosyphon loop
(Benne, K.S. and Homan K.0, Numerical Heat Transfer, 54(3), p 235-254, 2008).
United States Patent 5579830 discloses the use of an inclined heat pipe
for passively cooling an enclosure with the heat pipe located inside a thermal
storage
device with the heat exchange occurring on the outside of the storage device.
The
system does not interact with a separate cooling device to lower the overall
net
energy consumption, nor does it have active control of the amount of heat
exchanged.
In a similar application, United States Patent 7096928 teaches how to use a
flexible
thermosyphon loop to extract heat from electronic devices and United States
Patent
Application 2007/0242438 teaches the use of an inclined TPCT for the same
application. Canadian patent CA 2614540 Al teaches how to exchange heat
passively using a TPCT between two air ducts with forced air flow for building
HVAC
applications. There is considerable additional art for cooling electronic
devices,
including CPU's, using inclined TPCT and horizontal heat pipes. In all these
passive
cooling applications heat is extracted from an enclosure in real-time and
rejected
inside the room where the electronic device is located. In all these devices
the net
building heat load is unchanged as the rejected heat adds to the internal room
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temperature which adds to building energy transfer system requirements. The
art
does not teach how to passively reject the heat of cooling devices to the
outside
ambient air that surrounds the building envelop. All these passive electronic
cooling
devices are not subject to the condition that when vu(TR-T.) is negative there
is no
.. heat flow and they do not work. For the passive cooling apparatus
disclosed, this
condition occurs for extended periods of time in the order of hours or even
months.
In prior art, the use of a TPCT to reduce the energy consumed by
building cooling devices in real-time at temperature approximately between -
20oC to
+30oC cannot be found. The disclosed cooling apparatus of buildings adds to
the
known art. Freezers, refrigerators, server rooms, ice making machine for
hockey
arenas, HVAC, are just a few examples of cooling devices located in buildings
for
which the disclosed cooling apparatus can reduce energy use in real time.
There is a
need for an apparatus with the TPCT evaporator coupled to building cooling
devices
using a liquid coolant such that heat is rejected to the air outside the
building envelop.
Each TPCT can reduce the need to install separate vertical columns to secure
third
party devices like solar panels, wind mills, and telecommunication equipment
by way
of example, and can even be integrated into building structures to provide
load
bearing support.
The renewable cooling resource which characterizes energy available
for building cooling devices can be postulated to be v"(TR-T.), where v is the
wind
velocity measured 10 m above the ground available from weather stations, TR is
the
refrigeration temperature (e.g., -18oC for freezers, -5oC for supermarket
coolers,
>20oC for computer data centers, >25oC for barns), and T. is the outside
temperature. The term v"(TR-T.) is an intermittent renewable resource
available to
every type of building when the term is positive and can be integrated inside
building
CA 02925630 2016-03-31
cooling devices. The thermosyphon condenser is located either above the roof,
the
side of the building, or remotely above the ground level¨with the velocity at
the
condenser modified at each of these locations applying wind shear layer
scaling laws
and accounting for building or other structures impacting the boundary layer.
The
5 disclosed real-time passive cooling apparatus displaces energy used to
operate
building cooling devices in an amount that depends on the temperature set
point of
each cooling devices, the latitude and longitude coordinates of the building,
the shape
of the building, and the general landscape surrounding the building.
SUMMARY OF THE INVENTION
According to one aspect of the invention there is provided a heat
transfer system for use with a building having an envelope which separates an
interior
space of the building from a surrounding exterior of the building and a
cooling device
within the interior space of the building which requires cooling, the system
comprising:
a thermosyphon assembly comprising:
a closed thermosyphon chamber extending between an
evaporator section and a condenser section arranged to be located in direct
heat
exchanging relationship with ambient air in the surrounding exterior of the
building;
and
a two-phase fluid within the closed thermosyphon chamber;
a heat exchanger chamber receiving a heat transfer fluid therein which
at least partially surrounds the evaporator section of the thermosyphon
chamber such
that the heat transfer fluid is in direct heat exchanging relationship with
the evaporator
section of the thermosyphon chamber;
an insulation layer which insulates the evaporator section of the
thermosyphon chamber and the heat exchanger chamber relative to respective
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surroundings thereof;
piping for communicating between the heat exchanger chamber and the
cooling device in a closed loop such that the heat exchanger fluid is in heat
exchanging relationship with the cooling device; and
a pump for circulating the heat transfer fluid through the piping between
the cooling device and the heat exchanger chamber.
The present invention relates to using a plurality of TPCT to reduce
energy consumed by cooling devices located inside buildings. Each TPCT is
located
close to the building or is part of the building, and can have its own fluid
and internal
pressure optimized for the cooling device temperature requirement and design
constraints. Furthermore, each TPCT requires flowing a liquid coolant in a
closed-loop
piping network around each thermosyphon evaporator using a pump. The liquid
coolant is then circulated inside a plurality of building cooling devices.
Each TPCT
evaporator then passively extracts the heat from the liquid coolant, rejecting
that heat
via the TPCT condenser that is exposed to an air flow surrounding the building
envelop. The TPCT condenser can be located above the building rooftop, on the
side
of the building, or remotely above the ground level. Each TPCT condenser is
continuously subjected in real-time to a variable ambient air temperature and
wind
shear layer. At the same time, the TPCT evaporator is subjected to a variable
cooling
load depending on the requirements of building cooling devices. The disclosed
apparatus provides a method to remove heat from building cooling devices when
the
renewable cooling resource vcL6(TR-T..) is positive. To better match cooling
loads of
building devices with the renewable cooling resource outside the building
envelop, an
energy storage cavity that surrounds the evaporator and the liquid coolant can
be
added. The storage reduces the impact of the intermittency of the renewable
cooling
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resource to further decrease the energy used by cooling devices inside
buildings by
mitigating relatively large fluctuations in the wind velocity and changes in
ambient air
temperature. In addition, many buildings use vertical steel hollow members to
support
structural loads, and to support external devices like lights in a parking lot
and solar
panels. Each TPCT can be integrated into buildings as a load bearing member
and
can be used to secure third-party devices above ground.
Preferably the heat transfer fluid has a prescribed boiling point which is
outside of an operating temperature range of the heat exchanger chamber such
that
the heat transfer fluid does not undergo a phase change.
Preferably the two-phase fluid in the thermosyphon chamber is a
mixture of fluids having different boiling temperatures which does not undergo
a
phase change.
The heat exchanger chamber may comprise an annular portion which
fully surrounds the evaporator section of the thermosyphon chamber.
Preferably the system further includes an energy storage chamber
including an energy storage fluid therein which at least partially surrounds
one or both
of the evaporator section of the thermosyphon chamber and the heat exchanger
chamber. Preferably the insulation layer insulates the energy storage chamber,
the
evaporator section of the thermosyphon chamber, and the heat exchanger chamber
.. relative to the respective surroundings thereof.
When the heat exchanger chamber comprises an annular portion fully
surrounding the evaporator section of the thermosyphon chamber, the energy
storage
chamber preferably comprises an annular portion fully surrounding the heat
exchanger chamber, and the insulation layer preferably fully surrounds the
energy
storage chamber.
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An auxiliary energy storage tank may be further provided which includes
an energy storage fluid therein which is in heat exchanging relationship with
the piping
at a location downstream from the cooling device and upstream from the
thermosyphon assembly.
A plurality of thermosyphon assemblies may be provided in parallel
relationship with one another, in which each assembly comprises i) a closed
thermosyphon chamber extending between an evaporator section and a condenser
section arranged to be located in contact with ambient air in the surrounding
exterior
of the building, ii) a two-phase fluid within the closed thermosyphon chamber,
and iii)
a heat exchanger chamber which receives the heat transfer fluid therein and
which at
least partially surrounds the evaporator section of the thermosyphon chamber
such
that the heat transfer fluid is in direct heat exchanging relationship with
the evaporator
section thereof.
When provided in combination with a plurality of cooling devices, the
piping is preferably connected between the heat exchanger chamber and each of
the
cooling devices in parallel relationship with one another.
Preferably a controller is operatively connected to the pump so as to be
arranged to turn the pump on and off to control circulation of the heat
transfer fluid
through the piping. Preferably the controller is arranged to actuate the pump
in
response to a sensed temperature which exceeds an upper temperature limit of
the
system. The sensed temperature may be sensed by a temperature sensor in
communication with the cooling device or in communication with the heat
transfer
fluid.
The system may be used in combination with a cooling device
comprising a refrigeration cycle which is operational supplementary to the
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thermosyphon assembly.
When the system is used in combination with a cooling device
comprising a refrigeration cycle having a condenser section, the piping may be
in heat
exchanging relationship with the condenser section of the refrigeration cycle.
The thermosyphon assembly may extend through the envelope of the
building such that the evaporator section is located within the interior space
of the
building. In this instance, the thermosyphon assembly preferably further
comprises
an adiabatic section extending between the evaporator section and the
condenser
section such that the evaporator section and the condenser section are spaced
apart
from one another in which the adiabatic section is insulated relative to
respective
surroundings thereof.
The thermosyphon assembly may extend through a 'roof portion of the
building. The roof portion may include a main roof line and a well portion
recessed
relative to the main roof line, in which the condenser section is at least
partially
received within the well portion below the main roof line.
Preferably the thermosyphon assembly is located fully externally of the
building, for example on building grounds, laterally to one side of the
building.
The evaporator section of the thermosyphon evaporator may be located
below ground.
In some instances, a portion of a boundary wall of the thermosyphon
chamber may support a portion of a load of the building. The boundary wall of
the
thermosyphon chamber may also structurally support a load of an auxiliary
device
supported thereon.
A surface coating may be provided on an outside of the condenser
section of the thermosyphon chamber which reflects solar radiation to increase
the
CA 02925630 2016-03-31
heat transfer rate to ambient air.
A plurality of heat transfer fins may be mounted in conductive
relationship with at least one boundary wall of the condenser section of the
thermosyphon chamber to increase the heat transfer rate to the ambient air.
5 The system may further include an auxiliary refrigerant cycle
operatively
connected in heat exchanging relationship with the thermosyphon chamber in
proximity to the condenser section which actively cools the condenser section
when
ambient air is insufficient to meet cooling demands by the cooling device.
Various embodiments of the invention will now be described in
10 conjunction with the accompanying drawings in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevation cut away of an embodiment of the passive cooling
apparatus of the present invention located inside a building showing one
thermosyphon and one building cooling device.
FIG. 2 is an elevation cut away of a preferred embodiment of the
passive cooling apparatus of the present invention located inside a building
showing
one thermosyphon and one building cooling device with integrated energy
storage to
reduce the impact of the intermittency of the renewable cooling resource.
FIG. 3 is a plan view of an embodiment of multiple passive cooling
apparatus and building cooling devices with separate energy storage tank.
FIG. 4 is an elevation cut away of an embodiment of the passive cooling
apparatus of the present invention with the thermosyphon condenser extending
below
the main roof line.
FIG. 5 is an elevation cut away of an embodiment of the passive cooling
apparatus of the present invention located on the side of a building.
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FIG. 6 is an elevation cut away of an embodiment of the passive cooling
apparatus of the present invention located on the building grounds.
FIG. 7 is an elevation cut away of an embodiment of the passive cooling
apparatus of the present invention located inside a building showing one
thermosyphon and one building cooling device whose load is fully serviced by
disclosed cooling apparatus.
In the drawings like characters of reference indicate corresponding parts
in the different figures.
DETAILED DESCRIPTION
FIG 1 illustrates an embodiment of the invention showing a cross-
sectional view of part of building 2 using a real-time passive cooling system
to reduce
the energy consumed by cooling device 1 located in building 2. Cooling device
1
could be a plurality of such devices that performs a cooling function in real
time in
building 2 which by way of example, may be coolers, freezers, open refrigerate
vegetable counters, ice rink refrigeration systems, air conditioning devices,
heat
pumps, chillers, electronic equipment cabinets, computer server cooling
systems, etc.
Building 2 consists of roof 4, at least one floor 3, and walls which
collectively form a building envelope which separates an interior space of the
building
from ambient air in a surrounding exterior of the building.
Cooling device 1 is consuming energy to keep the temperature inside
cooling device 1 at a set temperature. The cooling device includes a target
object or
space which requires cooling and thus generates on ongoing cooling demand. The
cooling device may rely entirely on the system of the present invention to
meet the
cooling demand. Alternatively, the cooling device may employ a conventional
refrigeration cycle to assist in meeting the cooling demand by cooling the
target object
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or space only when the system of the present invention is not capable of
meeting the
cooling demand. Use of a refrigeration cycle in a supplementary manner to the
cooling of the system of the present invention is shown at the left side of
Figure 3.
Alternatively, the evaporator of the refrigeration cycle may be used to
directly meet
the cooling demands of the target object or space to be cooled, and the system
of the
present serves to remove heat from the condenser of the refrigeration cycle of
the
cooling device, as shown on the right side of Figure 3.
Thermosyphon assembly 5 is composed of closed loop pipe 6 defining a
thermosyphon chamber therein which is functionally subdivided in three
sections: a
thermosyphon evaporator 7, a thermosyphon condenser 9 longitudinally opposed
from the evaporator 7 at opposing ends relative to one another, and an
optional
thermosyphon adiabatic section 8 spanning between the evaporator and
condenser.
The chamber is partially filled with two-phase fluid 16.
Thermosyphon condenser 9 is exposed to and in direct heat exchanging
relationship with ambient air 11 having a variable temperature and moisture,
variable
solar radiation 15, and variable wind shear layer 10. Wind shear layer 10 on
roof 4
may have a lower disturbed region, is a function of the shape of building 2,
the
roughness terrain surrounding building 2, the wind velocity, and the wind
direction.
Fins 12 are optionally added to the outside of thermosyphon condenser 9 to
increase
heat transfer rate 13 to ambient air 11. Thermosyphon condenser 9 has exterior
finish 14 that reflects solar radiation 15 to increase heat transfer 13 to
ambient air 11.
Two-phase fluid 16 boils in thermosyphon evaporator 7 and the vapor
phase rises upwards in pipe 6 when the temperature of ambient air Ills below
the
vapor temperature inside thermosyphon evaporator 7. When the thermosyphon
vapor
flows, it passes through adiabatic section 8 and changes to a liquid phase in
13
thermosyphon condenser 9, creating liquid film 19, which flows downwards back
to
thermosyphon evaporator 7.
Pipe 20 forms cavity 21 between the inner wall of pipe 20 and the outer
wall of thermosyphon evaporator 7. The cavity 21 is a heat exchanger chamber
which
fully surrounds the circumference of the pipe forming the thermosyphon chamber
at
the evaporator section thereof. The heat exchanger chamber receives a heat
transfer
fluid therein which at least partially surrounds the evaporator section of the
thermosyphon chamber such that the heat transfer fluid is in direct heat
exchanging
relationship with the evaporator section of the thermosyphon chamber.
Preferably, insulation 17 is added as a continuous layer to restrict heat
loss to the building ambient air from pipe 20 and thermosyphon adiabatic
section 8.
The insulation layer forms a complete envelope which Insulates the evaporator
section of the thermosyphon chamber and the heat exchanger chamber relative to
respective surroundings thereof.
To reduce energy consumed by cooling device 1, pump 24 circulates
liquid coolant 18 through cavity 21 and cooling device 1 in closed-loop pipe
network
41. Controller 22 measures temperature of liquid coolant 18 and temperature
inside
cooling device 1 and controls operation of pump 24 accordingly. Optionally,
liquid
coolant 18 flowing through closed-loop pipe network 41 can be a slurry
composed of
liquid and solid phases, and can contain nanoparticies to improve heat
transfer. The
controller is thus operatively connected to the pump so as to be arranged to
turn the
pump on and off to control circulation of the heat transfer fluid through
piping which
communicates between the heat exchanger chamber and the cooling device in a
closed loop such that the heat exchanger fluid is in heat exchanging
relationship with
the cooling device. The controller is typically arranged to actuate the pump
in
Date Recue/Date Received 2022-06-06
CA 02925630 2016-03-31
14
response to a sensed temperature which exceeds an upper temperature limit of
the
system and to cease actuation of the pump when below a lower temperature limit
of
the system. The temperature may be sensed by a temperature sensor in
communication with the cooling device and/or a temperature sensor in
communication
with the heat transfer fluid.
Thermosyphon 5 optionally supports part of the weight of roof 4. More
particularly, in this instance at least a portion of a boundary wall of the
thermosyphon
chamber structurally supports at least a portion of a load of the building.
FIG 2 shows an alternative embodiment where an additional pipe 26 is
added to form energy storage cavity 27 formed between the inner wall of pipe
26 and
the outer wall of pipe 20. The energy storage chamber includes an energy
storage
fluid therein which at least partially surrounds one or both of the evaporator
section of
the thermosyphon chamber and the heat exchanger chamber. In this instance, the
insulation layer collectively envelopes and insulates the energy storage
chamber, the
evaporator section, and the heat exchanger chamber relative to the respective
surroundings thereof. Storage fluid 28 fills energy storage cavity 27 and
energy is
transferred through pipe 20. Optionally, storage fluid 28 can undergo phase
change
forming solid phase 29. Should storage fluid 28 expand when turning to solid
phase
29, potential for heaving is reduced by creating fluid layer melt 30 when pump
24 is
on. Controller 22 senses pressure in energy storage cavity 27 resulting from
formation of solid phase 29 and can shut off valve 31 to prevent damage.
Storage
fluid 28 can be a slurry composed of liquid and solid phases and contain
nanoparticles to enhance heat transfer. Thermosyphon condenser 9 can support a
plurality of third-party device 32 that require elevated support like solar
panels in this
embodiment.
CA 02925630 2016-03-31
FIG 3 shows an alternative embodiment where liquid coolant 18
circulates through closed-loop piping network 41, cavities 21, cooling devices
1, pump
24, and energy storage tank 40. Energy storage tank 40 contains storage fluid
28 that
can undergo phase change, can be a slurry composed of liquid and solid phases,
and
5 can
contain nanoparticles to improve heat transfer. The auxiliary energy storage
tank
40 which includes an energy storage fluid therein is thus in heat exchanging
relationship with the piping at a location downstream from the cooling device
and
upstream from the thermosyphon assembly.
FIG 3 also shows a plurality of thermosyphon assemblies in parallel
10
relationship with one another, in which each thermosyphon assembly comprises
i) a
closed thermosyphon chamber extending between an evaporator section and a
condenser section arranged to be located in contact with ambient air in the
surrounding exterior of the building, ii) a two-phase fluid within the closed
thermosyphon chamber, and iii) a heat exchanger chamber which receives the
heat
15
transfer fluid therein and which at least partially surrounds the evaporator
section of
the thermosyphon chamber such that the heat transfer fluid is in direct heat
exchanging relationship with the evaporator section thereof.
FIG 3 also shows a plurality of the cooling devices in which the piping is
connected between the heat exchanger chamber and each of the cooling devices
in
parallel relationship with one another. Liquid coolant 18 can be integrated
into cooling
device 1 by adding by way of example heat exchanger 51 and fan 52 that is
separate
of refrigeration cycle 25, and by way of on other example integrating heat
exchanger
53 into refrigeration cycle 25. Bypass valve 60 can redirect liquid coolant 17
to
energy storage tank 40.
FIG 4 shows an alternative embodiment to Fig 1 where roof 4 has a
16
built-in recess 42 that allows to' extended length of thermosyphon condenser 9
without
extending the height of thermosyphon 5, making more contact with ambient air
11. As
heat transfer rate 13 is mainly controlled by the exposure area of
thermosyphon
condenser 9 to the outside air, recess 42 helps increase heat transfer rate
13. Fins
12 can act as a rain and snow guard to prevent liquid accumulating at the
bottom of
the recess 42.
FIG 5 shows the real-time passive cooling apparatus located adjacent
to building side 52, with condenser 9 exposed to wind shear layer 10. Wind
shear
layer 10 may also be directed 900 to what is shown into or out of the figure.
Therrnosyphon evaporator 7 is shown located below ground level within ground
46.
Liquid coolant 8 circulates in closed-loop piping network 41 (partially shown)
to a
plurality of cooling devices 1 (not shown) inside building 2 (not shown).
FIG 8 shows a real-time passive cooling apparatus located remotely on
building grounds 45. Thermosyphon condenser 9 Is exposed to wind shear layer
10
and thermosyphon condenser 7 is located below ground level within ground 46.
Liquid coolant 18 circulates in closed-loop piping network 41 (partially
shown) to a
plurality of cooling device 1 (not shown) inside building 2. Parking lots
lights 47 are
secured to thermosyphon 5 in this embodiment.
FIG 7 shows an alternative embodiment where heat exchanger 50 is
added around thermosyphon adiabatic section 8 to actively remove the heat from
thermosyphon 5 when required. This allows to remove refrigeration cycles 25 In
cooling devices 1 and replace these with a larger refrigeration plant (not
shown) that
services each thermosyphon condenser 9 when required using refrigerant 52 and
building distribution piping 51.
The thermosyphon evaporator can be also located below ground in FIG
Date Recue/Date Received 2022-06-06
CA 02925630 2016-03-31
17
1, FIG 2 and FIG 4 and above ground in FIG 5 and FIG 6. Two-phase fluid 16
inside
thermosyphon 5 can be replaced by a fluid that does not undergo a phase change
resulting in higher internal heat transfer resistance. Said fluid can be a
mixture
composed of fluids that vaporize at different temperatures to maintain two-
phase heat
transfer rates over a wider range of operating temperatures. The disclosed
invention
can include a plurality of components interconnected using closed-loop piping
network
41: thermosyphon 5, building cooling device 5, energy storage cavity 27, pump
24,
and energy storage tank 40. In addition, the effect of wind shear layer 10
varies
depending if thermosyphon condenser 9 is located above roof 4, adjacent to
building
side 52, and above building ground 45 and can be predicted using fluid
dynamics
boundary layer scaling laws, experimental data, and computational methods to
predict
heat transfer rate 13 based on the available intermittent renewable cooling
resource
v .6(TR-T..).
Since various modifications can be made in my invention as herein
above described, it is intended that all matter contained in the accompanying
specification shall be interpreted as illustrative only and not in a limiting
sense.
