U.S. patent application number 15/217525 was filed with the patent office on 2017-03-02 for inclined heat exchanger with tapered ends.
The applicant listed for this patent is Trane International Inc.. Invention is credited to Stephen Stewart Hancock.
Application Number | 20170059188 15/217525 |
Document ID | / |
Family ID | 58103826 |
Filed Date | 2017-03-02 |
United States Patent
Application |
20170059188 |
Kind Code |
A1 |
Hancock; Stephen Stewart |
March 2, 2017 |
Inclined Heat Exchanger with Tapered Ends
Abstract
Systems and methods are disclosed that include providing a
heating, ventilation, and/or air conditioning (HVAC) system with a
tapered end heat exchanger (TEHE) having a first tapered end
disposed at a lower end of the TEHE with respect to an incoming
airflow and on the downstream face of the TEHE and having a second
tapered end disposed at an upper end of the TEHE with respect to an
incoming airflow and on the upstream face of the TEHE. A drain pan
having louvers is disposed about the lower end of the TEHE and
configured to restrict airflow through narrow portions of the first
tapered end of the TEHE. A baffle is disposed about the upper end
of the TEHE and configured to restrict airflow through narrow
portions of the second tapered end of the TEHE.
Inventors: |
Hancock; Stephen Stewart;
(Flint, TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Trane International Inc. |
Davidson |
NC |
US |
|
|
Family ID: |
58103826 |
Appl. No.: |
15/217525 |
Filed: |
July 22, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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62212915 |
Sep 1, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F25B 13/00 20130101;
F28F 2280/00 20130101; F24F 1/0003 20130101; F24F 13/08 20130101;
F24F 13/222 20130101; F28F 1/32 20130101; F25B 49/02 20130101; F28D
1/0443 20130101; F25B 39/00 20130101; F28D 2001/0266 20130101; F24F
1/0059 20130101 |
International
Class: |
F24F 1/00 20060101
F24F001/00; F28D 1/04 20060101 F28D001/04; F25B 13/00 20060101
F25B013/00; F28F 1/32 20060101 F28F001/32; F24F 13/08 20060101
F24F013/08; F28D 1/053 20060101 F28D001/053 |
Claims
1. A heat exchanger, comprising: an upstream face and a downstream
face; a plurality of tubes arranged in a plurality of rows; a
plurality of fins disposed along the tubes; and at least one
tapered end disposed on the heat exchanger, wherein the tapered end
is closer to being perpendicular to a primary incoming airflow
direction than at least one of the upstream face and the downstream
face of the heat exchanger.
2. The heat exchanger of claim 1, wherein the tapered end is
disposed on the downstream face of the heat exchanger.
3. The heat exchanger of claim 1, wherein the tapered end is
disposed on the upstream face of the heat exchanger.
4. The heat exchanger of claim 1, wherein a first row of tubes
comprises more tubes than a second row of tubes.
5. The heat exchanger of claim 4, wherein the second row of tubes
comprises more tubes than a third row of tubes.
6. The heat exchanger of claim 2, wherein a baffle is disposed at
least partially about the at least one tapered end.
7. The heat exchanger of claim 3, wherein a drain pan is disposed
at least partially about the at least one tapered end.
8. The heat exchanger of claim 7, wherein the drain pan comprises a
plurality of louvers.
9. The heat exchanger of claim 8, wherein the plurality of louvers
comprise different sizes and are configured to restrict airflow
through the at least one tapered end.
10. The heat exchanger of claim 3, further comprising: a second
tapered end disposed on an upstream side of the heat exchanger.
11. The heat exchanger of claim 10, wherein a baffle is disposed at
least partially about the second tapered end of the heat
exchanger.
12. The heat exchanger of claim 11, wherein the baffle is
configured to restrict airflow through the second tapered end.
13. The heat exchanger of claim 1, further comprising: a second
heat exchanger comprising at least one tapered end, wherein the
heat exchanger and the second heat exchanger are configured in at
least one of an A-frame arrangement and a V-frame arrangement.
14. The heat exchanger of claim 1, further comprising: a plurality
of heat exchangers, each comprising at least one tapered end,
wherein the plurality of heat exchangers are configured in at least
one of an N-frame arrangement, inverted N-frame arrangement,
M-frame arrangement, and a W-frame arrangement.
15. A heating, ventilation, and/or air conditioning (HVAC) system,
comprising: a heat exchanger comprising: an upstream face and a
downstream face; a plurality of tubes arranged in a plurality of
rows; a plurality of fins disposed along the tubes; and at least
one tapered end disposed on the heat exchanger, wherein the tapered
end is closer to being perpendicular to a primary incoming airflow
direction than at least one of the upstream face and the downstream
face of the heat exchanger.
16. The HVAC system of claim 15, wherein the at least one tapered
end is disposed on the downstream face of the heat exchanger.
17. The HVAC system of claim 15, wherein the at least one tapered
end is disposed on the upstream face of the heat exchanger.
18. The HVAC system of claim 16, wherein a baffle is disposed at
least partially about the at least one tapered end.
19. The HVAC system of claim 17, wherein a drain pan is disposed at
least partially about the at least one tapered end.
20. The HVAC system of claim 19, wherein the drain pan comprises a
plurality of louvers.
21. The HVAC system of claim 20, wherein the plurality of louvers
comprise different sizes and are configured to restrict airflow
through the at least one tapered end.
22. The HVAC system of claim 17, further comprising: a second
tapered end disposed on an upstream face of the heat exchanger,
wherein a baffle is disposed at least partially about an upper end
of the heat exchanger and configured to restrict airflow through
the second tapered end.
23. The HVAC system of claim 15, further comprising: a second heat
exchanger comprising at least one tapered end, wherein the heat
exchanger and the second heat exchanger are configured in at least
one of an A-frame arrangement and a V-frame arrangement.
24. The HVAC system of claim 1, further comprising: a plurality of
heat exchangers, each comprising at least one tapered end, wherein
the plurality of heat exchangers are configured in at least one of
an N-frame arrangement, inverted N-frame arrangement, M-frame
arrangement, and a W-frame arrangement.
25. The HVAC system of claim 11, wherein the heat exchanger is
disposed in an indoor unit of the HVAC system.
26. A method of operating a heating, ventilation, and/or air
conditioning (HVAC) system, comprising: providing at least one heat
exchanger comprising an upstream face, a downstream face, and at
least one tapered end in an HVAC system; orienting the tapered end
closer to perpendicular to a primary incoming airflow direction
than at least one of the upstream face and the downstream face of
the heat exchanger; operating the HVAC system in at least one of a
cooling mode and a heating mode; restricting an airflow through the
at least one tapered end of the heat exchanger; and exchanging heat
between the airflow and a refrigerant carried by the at least one
heat exchanger.
27. The method of claim 26, wherein the at least one tapered end is
disposed on an upstream face of the heat exchanger, and wherein a
baffle is disposed at least partially about the at least one
tapered end.
28. The method of claim 26, wherein the at least one tapered end is
disposed on an downstream face of the heat exchanger, and wherein a
drain pan is disposed at least partially about the at least one
tapered end.
29. The method of claim 27, wherein the restricting an airflow
through the at least one tapered end of the heat exchanger is
accomplished by disposing a baffle at least partially about the at
least one tapered end.
30. The method of claim 28, wherein the restricting an airflow
through the at least one tapered end of the heat exchanger is
accomplished by disposing a drain pan comprising a plurality of
louvers at least partially about the at least one tapered end.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority under 35 U.S.C.
119(e) to U.S. Provisional Patent Application No. 62/212,915 filed
on Sep. 1, 2015 by Stephen Stewart Hancock, and entitled "Inclined
Heat Exchanger with Tapered Ends," the disclosure of which is
hereby incorporated by reference in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO A MICROFICHE APPENDIX
[0003] Not applicable.
BACKGROUND
[0004] Heating, ventilation, and/or air conditioning (HVAC) systems
may generally be used in residential and/or commercial areas for
heating and/or cooling to create comfortable temperatures inside
those areas. Some HVAC systems may be split-type heat pump systems
that have an indoor and outdoor unit and are capable of cooling a
comfort zone by operating in a cooling mode for transferring heat
from a comfort zone to an ambient zone using a refrigeration cycle
and also generally capable of reversing the direction of
refrigerant flow through the components of the HVAC system so that
heat is transferred from the ambient zone to the comfort zone,
thereby heating the comfort zone. Such split type heat pump systems
commonly use an inclined heat exchanger as the indoor heat
exchanger due to characteristics such as efficient performance,
compact size, and cost effectiveness.
SUMMARY
[0005] In some embodiments of the disclosure, a heat exchanger is
disclosed as comprising: an upstream face and a downstream face; a
plurality of tubes arranged in a plurality of rows; a plurality of
fins disposed along the tubes; and at least one tapered end
disposed on the heat exchanger, wherein the tapered end is closer
to being perpendicular to a primary incoming airflow direction than
at least one of the upstream face and the downstream face of the
heat exchanger.
[0006] In other embodiments of the disclosure, a heating,
ventilation, and/or air conditioning (HVAC) system is disclosed as
comprising: a heat exchanger comprising: an upstream face and a
downstream face; a plurality of tubes arranged in a plurality of
rows; a plurality of fins disposed along the tubes; and at least
one tapered end disposed on the heat exchanger, wherein the tapered
end is closer to being perpendicular to a primary incoming airflow
direction than at least one of the upstream face and the downstream
face of the heat exchanger.
[0007] In other embodiments of the disclosure, a method of
operating a heating, ventilation, and/or air conditioning (HVAC)
system is disclosed as comprising: providing at least one heat
exchanger comprising an upstream face, a downstream face, and at
least one tapered end in an HVAC system; orienting the tapered end
closer to perpendicular to a primary incoming airflow direction
than at least one of the upstream face and the downstream face of
the heat exchanger; operating the HVAC system in at least one of a
cooling mode and a heating mode; restricting an airflow through the
at least one tapered end of the heat exchanger; and exchanging heat
between the airflow and a refrigerant carried by the at least one
heat exchanger.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] For a more complete understanding of the present disclosure
and the advantages thereof, reference is now made to the following
brief description, taken in connection with the accompanying
drawings and detailed description:
[0009] FIG. 1 is a schematic diagram of an HVAC system according to
an embodiment of the disclosure;
[0010] FIG. 2 is a schematic diagram of a tapered end heat
exchanger (TEHE) according to an embodiment of the disclosure;
[0011] FIG. 3 is a schematic diagram of a plurality of tapered end
heat exchangers (TEHE's) of FIG. 2 configured as an A-coil heat
exchanger according to an embodiment of the disclosure;
[0012] FIG. 4 is a schematic diagram of a plurality of tapered end
heat exchangers (TEHE's) of FIG. 2 configured as a V-coil heat
exchanger according to an embodiment of the disclosure; and
[0013] FIG. 5 is a flowchart of a method of operating an HVAC
system according to an embodiment of the disclosure.
DETAILED DESCRIPTION
[0014] In some cases, it may be desirable to provide a tapered end
heat exchanger (TEHE) in an indoor unit of an HVAC system. For
instance, the performance of traditional style heat exchangers is
often diminished due to poor airflow characteristics to some parts
of the heat exchanger, restricted airflow passing through the heat
exchanger, and/or portions of the heat exchanger that are disposed
in the airflow exhaust path of other portions of the heat
exchanger. By providing a tapered end heat exchanger in the indoor
unit of an HVAC system, the heat transfer efficiency of the tapered
end heat exchanger, the indoor unit, and/or the HVAC system may be
improved over traditional style rectangular and prior tapered-end
heat exchangers since the tapered ends of the tapered end heat
exchanger, the configuration of the tubes of the tapered end heat
exchanger, the configuration of a drain pan of the tapered end heat
exchanger, and/or the configuration of a top air baffle of the
tapered end heat exchanger may provide an increased airflow to
portions of the tapered end heat exchanger, provide a reduced
pressure drop and/or increased airflow through portions of the
tapered end heat exchanger, and/or provide fewer portions of the
tapered end heat exchanger disposed in the airflow exhaust path of
other portions of the tapered end heat exchanger.
[0015] Referring now to FIG. 1, a schematic diagram of an HVAC
system 100 is shown according to an embodiment of the disclosure.
Most generally, HVAC system 100 comprises a heat pump system that
may be selectively operated to implement one or more substantially
closed thermodynamic refrigeration cycles to provide a cooling
functionality (hereinafter "cooling mode") and/or a heating
functionality (hereinafter "heating mode"). The HVAC system 100,
configured as a heat pump system, generally comprises an indoor
unit 102, an outdoor unit 104, and a system controller 106 that may
generally control operation of the indoor unit 102 and/or the
outdoor unit 104.
[0016] Indoor unit 102 generally comprises an indoor air handling
unit comprising an indoor heat exchanger 108, an indoor fan 110, an
indoor metering device 112, and an indoor controller 124. The
indoor heat exchanger 108 may generally be configured to promote
heat exchange between refrigerant carried within internal tubing of
the indoor heat exchanger 108 and an airflow that may contact the
indoor heat exchanger 108 but that is segregated from the
refrigerant. In some embodiments, the indoor heat exchanger 108 may
comprise a plate-fin heat exchanger. However, in other embodiments,
indoor heat exchanger 108 may comprise a microchannel heat
exchanger and/or any other suitable type of heat exchanger.
[0017] The indoor fan 110 may generally comprise a centrifugal
blower comprising a blower housing, a blower impeller at least
partially disposed within the blower housing, and a blower motor
configured to selectively rotate the blower impeller. The indoor
fan 110 may generally be configured to provide airflow through the
indoor unit 102 and/or the indoor heat exchanger 108 to promote
heat transfer between the airflow and a refrigerant flowing through
the indoor heat exchanger 108. The indoor fan 110 may also be
configured to deliver temperature-conditioned air from the indoor
unit 102 to one or more areas and/or zones of a climate controlled
structure. The indoor fan 110 may generally comprise a mixed-flow
fan and/or any other suitable type of fan. The indoor fan 110 may
generally be configured as a modulating and/or variable speed fan
capable of being operated at many speeds over one or more ranges of
speeds. In other embodiments, the indoor fan 110 may be configured
as a multiple speed fan capable of being operated at a plurality of
operating speeds by selectively electrically powering different
ones of multiple electromagnetic windings of a motor of the indoor
fan 110. In yet other embodiments, however, the indoor fan 110 may
be a single speed fan.
[0018] The indoor metering device 112 may generally comprise an
electronically-controlled motor-driven electronic expansion valve
(EEV). In some embodiments, however, the indoor metering device 112
may comprise a thermostatic expansion valve, a capillary tube
assembly, and/or any other suitable metering device. In some
embodiments, while the indoor metering device 112 may be configured
to meter the volume and/or flow rate of refrigerant through the
indoor metering device 112, the indoor metering device 112 may also
comprise and/or be associated with a refrigerant check valve and/or
refrigerant bypass configuration when the direction of refrigerant
flow through the indoor metering device 112 is such that the indoor
metering device 112 is not intended to meter or otherwise
substantially restrict flow of the refrigerant through the indoor
metering device 112.
[0019] Outdoor unit 104 generally comprises an outdoor heat
exchanger 114, a compressor 116, an outdoor fan 118, an outdoor
metering device 120, a reversing valve 122, and an outdoor
controller 126. In some embodiments, the outdoor unit 104 may also
comprise a plurality of temperature sensors for measuring the
temperature of the outdoor heat exchanger 114, the compressor 116,
and/or the outdoor ambient temperature. The outdoor heat exchanger
114 may generally be configured to promote heat transfer between a
refrigerant carried within internal passages of the outdoor heat
exchanger 114 and an airflow that contacts the outdoor heat
exchanger 114 but that is segregated from the refrigerant. In some
embodiments, outdoor heat exchanger 114 may comprise a plate-fin
heat exchanger. However, in other embodiments, outdoor heat
exchanger 114 may comprise a spine-fin heat exchanger, a
microchannel heat exchanger, or any other suitable type of heat
exchanger.
[0020] The compressor 116 may generally comprise a variable speed
scroll-type compressor that may generally be configured to
selectively pump refrigerant at a plurality of mass flow rates
through the indoor unit 102, the outdoor unit 104, and/or between
the indoor unit 102 and the outdoor unit 104. In some embodiments,
the compressor 116 may comprise a rotary type compressor configured
to selectively pump refrigerant at a plurality of mass flow rates.
In alternative embodiments, however, the compressor 116 may
comprise a modulating compressor that is capable of operation over
a plurality of speed ranges, a reciprocating-type compressor, a
single speed compressor, and/or any other suitable refrigerant
compressor and/or refrigerant pump. In some embodiments, the
compressor 116 may be controlled by a compressor drive controller
144, also referred to as a compressor drive and/or a compressor
drive system.
[0021] The outdoor fan 118 may generally comprise an axial fan
comprising a fan blade assembly and fan motor configured to
selectively rotate the fan blade assembly. The outdoor fan 118 may
generally be configured to provide airflow through the outdoor unit
104 and/or the outdoor heat exchanger 114 to promote heat transfer
between the airflow and a refrigerant flowing through the indoor
heat exchanger 108. The outdoor fan 118 may generally be configured
as a modulating and/or variable speed fan capable of being operated
at a plurality of speeds over a plurality of speed ranges. In other
embodiments, the outdoor fan 118 may comprise a mixed-flow fan, a
centrifugal blower, and/or any other suitable type of fan and/or
blower, such as a multiple speed fan capable of being operated at a
plurality of operating speeds by selectively electrically powering
different multiple electromagnetic windings of a motor of the
outdoor fan 118. In yet other embodiments, the outdoor fan 118 may
be a single speed fan. Further, in other embodiments, however, the
outdoor fan 118 may comprise a mixed-flow fan, a centrifugal
blower, and/or any other suitable type of fan and/or blower.
[0022] The outdoor metering device 120 may generally comprise a
thermostatic expansion valve. In some embodiments, however, the
outdoor metering device 120 may comprise an
electronically-controlled motor driven EEV similar to indoor
metering device 112, a capillary tube assembly, and/or any other
suitable metering device. In some embodiments, while the outdoor
metering device 120 may be configured to meter the volume and/or
flow rate of refrigerant through the outdoor metering device 120,
the outdoor metering device 120 may also comprise and/or be
associated with a refrigerant check valve and/or refrigerant bypass
configuration when the direction of refrigerant flow through the
outdoor metering device 120 is such that the outdoor metering
device 120 is not intended to meter or otherwise substantially
restrict flow of the refrigerant through the outdoor metering
device 120.
[0023] The reversing valve 122 may generally comprise a four-way
reversing valve. The reversing valve 122 may also comprise an
electrical solenoid, relay, and/or other device configured to
selectively move a component of the reversing valve 122 between
operational positions to alter the flowpath of refrigerant through
the reversing valve 122 and consequently the HVAC system 100.
Additionally, the reversing valve 122 may also be selectively
controlled by the system controller 106 and/or an outdoor
controller 126.
[0024] The system controller 106 may generally be configured to
selectively communicate with an indoor controller 124 of the indoor
unit 102, an outdoor controller 126 of the outdoor unit 104 and/or
other components of the HVAC system 100. In some embodiments, the
system controller 106 may be configured to control operation of the
indoor unit 102 and/or the outdoor unit 104. In some embodiments,
the system controller 106 may be configured to monitor and/or
communicate with a plurality of temperature sensors associated with
components of the indoor unit 102, the outdoor unit 104, and/or the
ambient outdoor temperature. Additionally, in some embodiments, the
system controller 106 may comprise a temperature sensor and/or may
further be configured to control heating and/or cooling of zones
associated with the HVAC system 100. In other embodiments, however,
the system controller 106 may be configured as a thermostat for
controlling the supply of conditioned air to zones associated with
the HVAC system 100.
[0025] The system controller 106 may also generally comprise a
touchscreen interface for displaying information and for receiving
user inputs. The system controller 106 may display information
related to the operation of the HVAC system 100 and may receive
user inputs related to operation of the HVAC system 100. However,
the system controller 106 may further be operable to display
information and receive user inputs tangentially and/or unrelated
to operation of the HVAC system 100. In some embodiments, however,
the system controller 106 may not comprise a display and may derive
all information from inputs from remote sensors and remote
configuration tools.
[0026] In some embodiments, the system controller 106 may be
configured for selective bidirectional communication over a
communication bus 128. In some embodiments, portions of the
communication bus 128 may comprise a three-wire connection suitable
for communicating messages between the system controller 106 and
one or more of the HVAC system 100 components configured for
interfacing with the communication bus 128. Still further, the
system controller 106 may be configured to selectively communicate
with HVAC system 100 components and/or any other device 130 via a
communication network 132. In some embodiments, the communication
network 132 may comprise a telephone network, and the other device
130 may comprise a telephone. In some embodiments, the
communication network 132 may comprise the Internet, and the other
device 130 may comprise a smartphone and/or other Internet-enabled
mobile telecommunication device. In other embodiments, the
communication network 132 may also comprise a remote server.
[0027] The indoor controller 124 may be carried by the indoor unit
102 and may generally be configured to receive information inputs,
transmit information outputs, and/or otherwise communicate with the
system controller 106, the outdoor controller 126, and/or any other
device 130 via the communication bus 128 and/or any other suitable
medium of communication. In some embodiments, the indoor controller
124 may be configured to communicate with an indoor personality
module 134 that may comprise information related to the
identification and/or operation of the indoor unit 102. In some
embodiments, the indoor controller 124 may be configured to receive
information related to a speed of the indoor fan 110, transmit a
control output to an electric heat relay, transmit information
regarding an indoor fan 110 volumetric flow-rate, communicate with
and/or otherwise affect control over an air cleaner 136, and
communicate with an indoor EEV controller 138. In some embodiments,
the indoor controller 124 may be configured to communicate with an
indoor fan controller 142 and/or otherwise affect control over
operation of the indoor fan 110. In some embodiments, the indoor
personality module 134 may comprise information related to the
identification and/or operation of the indoor unit 102 and/or a
position of the outdoor metering device 120.
[0028] The indoor EEV controller 138 may be configured to receive
information regarding temperatures and/or pressures of the
refrigerant in the indoor unit 102. More specifically, the indoor
EEV controller 138 may be configured to receive information
regarding temperatures and pressures of refrigerant entering,
exiting, and/or within the indoor heat exchanger 108. Further, the
indoor EEV controller 138 may be configured to communicate with the
indoor metering device 112 and/or otherwise affect control over the
indoor metering device 112. The indoor EEV controller 138 may also
be configured to communicate with the outdoor metering device 120
and/or otherwise affect control over the outdoor metering device
120.
[0029] The outdoor controller 126 may be carried by the outdoor
unit 104 and may be configured to receive information inputs,
transmit information outputs, and/or otherwise communicate with the
system controller 106, the indoor controller 124, and/or any other
device via the communication bus 128 and/or any other suitable
medium of communication. In some embodiments, the outdoor
controller 126 may be configured to communicate with an outdoor
personality module 140 that may comprise information related to the
identification and/or operation of the outdoor unit 104. In some
embodiments, the outdoor controller 126 may be configured to
receive information related to an ambient temperature associated
with the outdoor unit 104, information related to a temperature of
the outdoor heat exchanger 114, and/or information related to
refrigerant temperatures and/or pressures of refrigerant entering,
exiting, and/or within the outdoor heat exchanger 114 and/or the
compressor 116. In some embodiments, the outdoor controller 126 may
be configured to transmit information related to monitoring,
communicating with, and/or otherwise affecting control over the
compressor 116, the outdoor fan 118, a solenoid of the reversing
valve 122, a relay associated with adjusting and/or monitoring a
refrigerant charge of the HVAC system 100, a position of the indoor
metering device 112, and/or a position of the outdoor metering
device 120. The outdoor controller 126 may further be configured to
communicate with and/or control a compressor drive controller 144
that is configured to electrically power and/or control the
compressor 116.
[0030] The HVAC system 100 is shown configured for operating in a
so-called heating mode in which heat may generally be absorbed by
refrigerant at the outdoor heat exchanger 114 and rejected from the
refrigerant at the indoor heat exchanger 108. Starting at the
compressor 116, the compressor 116 may be operated to compress
refrigerant and pump the relatively high temperature and high
pressure compressed refrigerant through the reversing valve 122 and
to the indoor heat exchanger 108, where the refrigerant may
transfer heat to an airflow that is passed through and/or into
contact with the indoor heat exchanger 108 by the indoor fan 110.
After exiting the indoor heat exchanger 108, the refrigerant may
flow through and/or bypass the indoor metering device 112, such
that refrigerant flow is not substantially restricted by the indoor
metering device 112. Refrigerant generally exits the indoor
metering device 112 and flows to the outdoor metering device 120,
which may meter the flow of refrigerant through the outdoor
metering device 120, such that the refrigerant downstream of the
outdoor metering device 120 is at a lower pressure than the
refrigerant upstream of the outdoor metering device 120. From the
outdoor metering device 120, the refrigerant may enter the outdoor
heat exchanger 114. As the refrigerant is passed through the
outdoor heat exchanger 114, heat may be transferred to the
refrigerant from an airflow that is passed through and/or into
contact with the outdoor heat exchanger 114 by the outdoor fan 118.
Refrigerant leaving the outdoor heat exchanger 114 may flow to the
reversing valve 122, where the reversing valve 122 may be
selectively configured to divert the refrigerant back to the
compressor 116, where the refrigeration cycle may begin again.
[0031] Alternatively, to operate the HVAC system 100 in a so-called
cooling mode, most generally, the roles of the indoor heat
exchanger 108 and the outdoor heat exchanger 114 are reversed as
compared to their operation in the above-described heating mode.
For example, the reversing valve 122 may be controlled to alter the
flow path of the refrigerant from the compressor 116 to outdoor
heat exchanger 114 first and then to the indoor heat exchanger 108,
the indoor metering device 112 may be enabled, and the outdoor
metering device 120 may be disabled and/or bypassed. In cooling
mode, heat may generally be absorbed by refrigerant at the indoor
heat exchanger 108 and rejected by the refrigerant at the outdoor
heat exchanger 114. As the refrigerant is passed through the indoor
heat exchanger 108, the indoor fan 110 may be operated to move air
into contact with the indoor heat exchanger 108, thereby
transferring heat to the refrigerant from the air surrounding the
indoor heat exchanger 108. Additionally, as refrigerant is passed
through the outdoor heat exchanger 114, the outdoor fan 118 may be
operated to move air into contact with the outdoor heat exchanger
114, thereby transferring heat from the refrigerant to the air
surrounding the outdoor heat exchanger 114.
[0032] Referring now to FIG. 2, a schematic diagram of a tapered
end heat exchanger (TEHE) 200 is shown according to an embodiment
of the disclosure. The TEHE 200 may generally be configured as
and/or employed as the indoor heat exchanger 108 of FIG. 1 and
disposed in the indoor unit 102 of HVAC system 100. The TEHE 200
generally comprises a plurality of tubes 202 arranged in a
plurality of rows 204, 206, 208 and disposed longitudinally through
a plurality of adjacently disposed fins 210, a drain pan 212, and a
baffle 216. Most generally, in this embodiment, the arrangement of
the tubes 202 and the fins 210 give the TEHE 200 a shape that
includes an upstream face 218, a downstream face 220 that is
substantially parallel to the upstream face 218, a first tapered
end 222 that forms an angle 232 with the upstream face 218, a
second tapered end 224 that forms an angle 234 with the downstream
face 220, a lower end 226 that is substantially orthogonal to each
of the faces 218, 220 and disposed between the downstream face 220
and the first tapered end 222, and an upper end 228 that is also
substantially orthogonal to each of the faces 218, 220 and disposed
between the upstream face 218 and the second tapered end 224. In
some embodiments, the upstream face 218 and the downstream face 220
may be not be substantially parallel to one another, and/or the
lower end 226 and/or the upper end 228 may not be orthogonal to the
upstream face 218 and/or the downstream face 220.
[0033] The plurality of longitudinally finned tubes 202 and/or fins
210 are generally configured to carry a refrigerant, gas, liquid,
and/or other suitable heat transfer medium configured to exchange
heat with an airflow 230 passing between adjacent tubes 202 and/or
adjacent fins 210. The tubes 202 and/or the fins 210 may generally
be constructed of copper, stainless steel, aluminum, and/or another
suitable material suitable for promoting heat transfer between the
heat exchange medium carried within the tubes 202 and the airflow
230. In some embodiments, the tubes 202 may extend through and
beyond a fin 210 located at each end of the TEHE 200 and be joined
in fluid communication with another tube 202 and/or plurality of
tubes 202 by a hairpin joint and/or U-joint to form the fluid
circuit through the TEHE 200. However, in other embodiments, the
tubes 202 may be arranged in a plurality of parallel flowpaths and
connected at each end of the TEHE 200 by a header and/or plurality
of header to form the fluid circuit through the TEHE 200.
[0034] The plurality of longitudinally finned tubes 202 are
generally arranged in a plurality of rows 204, 206, 208. The first
row 204 of tubes 202 represents a row of tubes 202 that directly
receives the airflow 230 coming from the primary incoming airflow
direction 236 without first contacting another tube 202 not in the
first row 204 of the TEHE 200. The first row 204 of tubes may
generally extend along the upstream face 218 and the first tapered
end 222 of the TEHE 200. The second row 206 of tubes 202 represents
a row of tubes 202 disposed downstream from the first row 204 of
tubes 202 with respect to the airflow 230 through the TEHE 230 that
receives the airflow 230 after passing between and/or contacting
adjacently located tubes 202 in the first row 204. The third row
208 of tubes 202 represents a row of tubes 202 disposed downstream
from the second row 206 of tubes 202 with respect to the airflow
230 through the TEHE 230 that receives the airflow 230 after
passing between and/or contacting adjacently located tubes 202 in
the second row 206. Additionally, while the TEHE 200 is depicted as
comprising three rows, in some embodiments, the TEHE 200 may
comprise as few as two rows or any number of additional rows as a
result of the size and/or other design criteria of the TEHE
200.
[0035] As stated, the first tapered end 222 and the second tapered
end 224 generally form angles 232, 234 with the upstream face 218
and the downstream face 220, respectively. Accordingly, the angle
formed between the first tapered end 222 and the adjacently located
upstream face 218 may be referred to as the angle 232 of the first
tapered end 222, and the angle formed between the second tapered
end 224 and the adjacently located downstream face 220 may be
referred to as the angle 234 of the second tapered end 224.
Additionally, the tapered ends 222, 224 are oriented so that each
tapered end 222, 224 is closer to being perpendicular to a primary
incoming airflow direction 236 than the respective faces 218, 220
that the tapered ends 222, 224 form an angle with. In some
embodiments, the first tapered end 222 and the second tapered end
224 may comprise substantially similar angles 232, 234. However, in
other embodiments, the first tapered end 222 and the second tapered
end 224 may comprise different angles 232, 234. In some
embodiments, the angles 232, 234 may depend on the number of tubes
202 in each of the first row 204, second row 206, and third row
208. In some embodiments, the angles 232, 234 may be at least about
10 degrees, at least about 15 degrees, at least about 20 degrees,
at least about 25 degrees, at least about 30 degrees, at least
about 35 degrees, at least about 40 degrees, at least about 45
degrees, and/or at least about 50 degrees.
[0036] As compared to a traditional style rectangular and prior
tapered-end heat exchanger, the tapered ends 222, 224 of the TEHE
200 allow more tubes 202 to be disposed in the first row 204. This
is important because the temperature differential between the
airflow 230 and the refrigerant carried within the first row 204 of
tubes 202 is higher than between the airflow 230 and any other row
of tubes 202. Thus, the first row 204 of tubes has a higher heat
transfer efficiency than subsequent downstream rows 206, 208. As a
result of an increased number of first row 204 tubes 202, more
tubes 202 may be disposed in the second row 206, and fewer tubes
may be disposed in the third row 208 as compared to a traditional
style heat exchanger. Accordingly, by providing more tubes 202 in
the first row 204, the number of tubes 202 in the downstream
exhaust flow path of upstream tubes 202, the TEHE 200 provides an
increased efficiency over a traditional style heat exchanger. For
example, in this embodiment, the first row 204 comprises twenty
tubes 202, the second row 206 comprises sixteen tubes 202, and the
third row 208 comprises twelve tubes 202. Because tubes 202
disposed downstream from other tubes may experience about a 20%
heat transfer efficiency loss with respect to the upstream row of
tubes 202, the efficiency of the TEHE 200 may be calculated by
multiplying the number of tubes 202 by the efficiency of the
respective row that the tubes 202 are disposed in. Thus, in this
embodiment, TEHE 200 comprises an efficiency of
20(1.0)+16(0.8)+12(0.64)=40.48. In contrast, a similar size
traditional heat exchanger may comprise fifteen first row tubes,
fourteen second row tubes, and fourteen third row tubes. Thus, the
efficiency of a traditional style heat exchanger may be
15(1.0)+14(0.8)+14(0.64)=35.16.
[0037] Furthermore, traditional style rectangular and prior
tapered-end heat exchangers suffer from a high pressure drop at the
upper and the lower ends of the heat exchanger. The tapered ends
222, 224 of the TEHE 200 however have a fewer number of tubes 202
and thus may provide less resistance to the airflow 230 passing
between the tubes 202 and/or the fins 210 disposed within the
tapered end 222, 224 sections. Accordingly, the TEHE 200 may
experience a reduced pressure drop through the tapered ends 222,
224 of the TEHE 200 as compared to a traditional style heat
exchanger. However, it is well known that excessive airflow through
a heat exchanger may reduce the efficiency. To prevent excessive
airflow through the TEHE 200, the TEHE 200 comprises a drain pan
212 disposed at the lower end 226 of the TEHE 200 and a baffle 216
disposed at the upper end 228 of the TEHE 200.
[0038] The drain pan 212 is disposed about the lower end 226 of the
TEHE 200. The drain pan 212 may generally extend along the first
tapered end 222 and form a concavity 213 in the lower portion of
the drain pan 212 that extends around the lower end 226 of the TEHE
200 and vertically along the downstream face 220. The concavity may
generally be configured to catch and/or receive condensate that may
form on the tubes 202 and/or the fins 210. In some embodiments, the
drain pan 212 may comprise a channel, tube, and/or plurality of
tubes for carrying away condensate from the concavity 213 of the
drain pan 212. The drain pan 212 also comprises a plurality of
louvers 214, each louver 214 forming a vent 215 in the drain pan
212, disposed along the portion of the drain pan 212 that extends
along the first tapered end 222. The louvers 214 may generally be
configured to overlap such that condensate that falls onto an inner
surface of the drain pan 212 is carried into the concavity 213 of
the drain pan 212 and so that condensate does not escape through
the vents 215. Additionally, the louvers 214 are also configured to
allow the airflow 230 to reach the first tapered end 222 of the
TEHE 200 by passing through the vents 215 and subsequently through
the TEHE 200. The louvers 214 and/or the vents 215 may also
regulate air flow through the narrow portions of the TEHE 200 by
increasing the obstruction typically caused by a drain pan without
louvers while maximizing an upstream face 218 contact area of the
TEHE 200.
[0039] In some embodiments, the louvers 214 and/or the vents 215
may comprise substantially similar sizes. However, in some
embodiments, the louvers 214 and/or the vents 215 may comprise
different sizes to control a pressure drop through the TEHE 200
and/or restrict airflow 230 reaching the narrow portions of the
first tapered end 222 of the TEHE 200. In some embodiments, a
larger louver 214 may be associated with a smaller vent 215, and a
smaller louver 214 may be associated with a larger vent 215.
Accordingly, in some embodiments, the vents 215 disposed closer to
the lower end 226 may be smaller and/or the louvers 214 disposed
closer to the lower end 226 may be larger as compared with the
louvers 214 and the vents 215 disposed closer to the upstream face
218 of the TEHE 200. Thus, in some embodiments, the louvers 214 may
gradually decrease in size and the vents 215 may increase in size
with the largest louver 214 and smallest vent being located closest
to the lower end 226, and the smallest louver 214 and the largest
vent 215 being located the furthest from the lower end 226. As
such, the thinnest portion of the TEHE 200 that is disposed closest
to the lower end 226 may receive a substantially more restricted
airflow 230 as compared to thicker portions of the TEHE 200
disposed further from the lower end 226.
[0040] The baffle 216 is disposed about the upper end 228 of the
TEHE 200. The baffle 216 may generally extend slightly along the
second tapered end 224, around the upper end 228 of the TEHE 200,
vertically along the upstream face 218 and parallel with the
primary incoming airflow direction 236, and horizontally from the
vertical portion to the upstream face 218. The baffle 216 may
generally be disposed substantially close to each of the second
tapered end 224, the upper end 228, and the upstream face 218, so
that only a minimal gap exists between the baffle 216 and the
adjacent fins 210 of the TEHE 200. The baffle is generally
configured to restrict the airflow 230 passing through the narrow
portions of the second tapered end 224 of the TEHE 200. In some
embodiments, restricting the airflow 230 may control the pressure
drop through the TEHE 200 and may also increase the efficiency of
the TEHE 200. By providing the louvers 214 in the drain pan 212 and
the baffle 216 at each respective end 226, 228 of the TEHE 200,
airflow 230 is able to contact substantially all tubes 202 of the
TEHE 200, thereby providing no "dead air" and/or "inactive"
portions within the TEHE 200. Additionally, by restricting airflow
230 through the first tapered end 222 and the second tapered end
224 with the drain pan 212 louvers 214 and the baffle 216,
respectively, the airflow 230 through the narrow portions of the
TEHE 200 associated with the tapered ends 222, 224 may be
controlled in order to prevent too much airflow 230 through these
portions of the TEHE 200, thereby providing a more uniform airflow
230 through the TEHE 200 and preserving and/or increasing the heat
transfer efficiency of the TEHE 200 over traditional style heat
exchangers.
[0041] Referring now to FIG. 3, a schematic diagram of a plurality
of tapered end heat exchangers (TEHE's) 200 of FIG. 2 configured as
an A-coil heat exchanger 300 is shown according to an embodiment of
the disclosure. It will be appreciated that the A-coil heat
exchanger 300 may also be referred to as an "A-frame" heat
exchanger. Additionally, in embodiments employing multiple TEHE's
200, each TEHE 200 may be referred to as a "slab." Heat exchanger
300 comprises two TEHE 200 heat exchangers configured in an A-coil
arrangement, at least one drain pan 312, and at least one baffle
316. In some embodiments, the at least one drain pan 312 of the
heat exchanger 300 may comprise two separate drain pans 212 of FIG.
2. However, in other embodiments, the drain pan 312 may be a single
unit and comprise other features that join two drain pans 212 of
FIG. 2 together as a single, unitary drain pan. Additionally, in
some embodiments, the baffle 316 may comprise a single unit that
represents two baffles 216 of FIG. 2 joined together as a single
unitary baffle along the vertical portion vertically that extends
along the upstream face 218 and that is substantially parallel with
a primary incoming airflow direction 336. However, in other
embodiments, the baffle 316 may comprise two separate baffles 216
of FIG. 2 that may substantially abut one another.
[0042] Referring now to FIG. 4, a schematic diagram of a plurality
of tapered end heat exchangers (TEHE's) 200 of FIG. 2 configured as
a V-coil heat exchanger 400 is shown according to an embodiment of
the disclosure. It will be appreciated that the V-coil heat
exchanger 400 may also be referred to as a "V-frame" heat
exchanger. Heat exchanger 400 comprises two TEHE 200 heat
exchangers configured in a V-coil arrangement, at least one drain
pan 412, and at least one baffle 416. In some embodiments, the at
least one drain pan 412 of heat exchanger 400 may comprise two
separate drain pans 212 of FIG. 2 that substantially abut one
another along the vertical portion that extends along the
downstream face 220 of the TEHE 200. In such embodiments, the drain
pan 412 may comprise tubes that connect each concavity 213 in fluid
communication. However, in alternative embodiments, the drain pan
412 may be a single unit that represents two drain pans 212 of FIG.
2 joined together as a single unitary drain pan along the vertical
portion that extends along the downstream face 220 of the TEHE 200.
In such alternative embodiments, the drain pan 412 may not comprise
the vertical portion, such that the drain pan 412 comprises a
single concavity that envelopes the lower end 226 of each TEHE 200
and that is configured to collect condensate. Additionally, in some
embodiments, the baffle 416 may comprise two separate baffles 216
of FIG. 2. However, in other embodiments, the baffle 416 may
comprise a single unit and comprise other features that join two
baffles 216 of FIG. 2 together as a single, unitary baffle.
[0043] It will be appreciated that while A-frame and V-frame heat
exchangers are shown, this disclosure expressly contemplates the
use of other configurations of heat exchangers. For example,
alternative embodiments of heat exchangers may be configured as a
W-coil ("W-frame"), M-coil ("M-frame"), N-coil ("N-frame"),
inverted N-Coil ("inverted N-frame"), and/or any other configured
slab type heat exchanger that employs multiple TEHE's 200 of FIG.
2, multiple heat exchangers 300 of FIG. 3, and/or multiple heat
exchangers 400 of FIG. 4.
[0044] Referring now to FIG. 5 is a flowchart of a method 500 of
operating an HVAC system is shown according to an embodiment of the
disclosure. The method 500 may begin at block 502 by providing at
least one tapered end heat exchanger (TEHE) 200 in an HVAC system.
In some embodiments, the TEHE 200 may be a standalone TEHE 200,
heat exchanger 300, and/or heat exchanger 400. In some embodiments,
the at least one TEHE 200 may be installed in the indoor unit 102
of HVAC system 100. The method 500 may continue at block 504 by
operating the HVAC system in at least one of a cooling mode and a
heating mode. The method may continue at block 506 by restricting
an airflow through tapered end portions of the TEHE 200. In some
embodiments, the airflow 230 may be restricted through a first
tapered end 222 by providing louvers 214 in a drain pan 212, and
the airflow 230 may be restricted through a second tapered end 224
by a baffle 216. The method 500 may conclude at block 508 by
exchanging heat between the airflow and a refrigerant carried by
the at least one TEHE 200. In some embodiments, the airflow may be
airflow 230 generated by indoor fan 110 of HVAC system 100.
Additionally, in some embodiments, the refrigerant may be carried
by tubes 202 of TEHE 200.
[0045] At least one embodiment is disclosed and variations,
combinations, and/or modifications of the embodiment(s) and/or
features of the embodiment(s) made by a person having ordinary
skill in the art are within the scope of the disclosure.
Alternative embodiments that result from combining, integrating,
and/or omitting features of the embodiment(s) are also within the
scope of the disclosure. Where numerical ranges or limitations are
expressly stated, such express ranges or limitations should be
understood to include iterative ranges or limitations of like
magnitude falling within the expressly stated ranges or limitations
(e.g., from about 1 to about 10 includes, 2, 3, 4, etc.; greater
than 0.10 includes 0.11, 0.12, 0.13, etc.). For example, whenever a
numerical range with a lower limit, R.sub.1, and an upper limit,
R.sub.u, is disclosed, any number falling within the range is
specifically disclosed. In particular, the following numbers within
the range are specifically disclosed:
R=R.sub.1+k*(R.sub.u-R.sub.1), wherein k is a variable ranging from
1 percent to 100 percent with a 1 percent increment, i.e., k is 1
percent, 2 percent, 3 percent, 4 percent, 5 percent, . . . , 50
percent, 51 percent, 52 percent, . . . , 95 percent, 96 percent, 97
percent, 98 percent, 99 percent, or 100 percent. Unless otherwise
stated, the term "about" shall mean plus or minus 10 percent of the
subsequent value. Moreover, any numerical range defined by two R
numbers as defined in the above is also specifically disclosed. Use
of the term "optionally" with respect to any element of a claim
means that the element is required, or alternatively, the element
is not required, both alternatives being within the scope of the
claim. Use of broader terms such as comprises, includes, and having
should be understood to provide support for narrower terms such as
consisting of, consisting essentially of, and comprised
substantially of. Accordingly, the scope of protection is not
limited by the description set out above but is defined by the
claims that follow, that scope including all equivalents of the
subject matter of the claims. Each and every claim is incorporated
as further disclosure into the specification and the claims are
embodiment(s) of the present invention.
* * * * *