US20200370841A1

US20200370841A1 - Heat exchanger assembly for an hvac system

Info

Publication number: US20200370841A1
Application number: US16/508,122
Authority: US
Inventors: Kirankumar A. Muley; Sumedh J. Suryawanshi; Manian A K S
Original assignee: Johnson Controls Technology Co
Current assignee: Johnson Controls Tyco IP Holdings LLP
Priority date: 2019-05-24
Filing date: 2019-07-10
Publication date: 2020-11-26

Abstract

A heat exchanger includes a tube configured to direct a working fluid therethrough. The heat exchanger also includes a fin disposed about the tube and having a louver, where the tube and the fin are made of a polymeric material.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from and the benefit of U.S. Provisional Application Ser. No. 62/852,856, entitled “HEAT EXCHANGER ASSEMBLY FOR AN HVAC SYSTEM,” filed May 24, 2019, which is herein incorporated by reference in its entirety for all purposes.

BACKGROUND

This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present techniques, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light and not as an admission of any kind.
A heating, ventilation, and/or air conditioning (HVAC) system may be used to thermally regulate an environment, such as a space within a building, home, or other structure. The HVAC system may include heat exchangers, such as a condenser, an evaporator, and/or a hydronic coil, which may be utilized to transfer thermal energy between the HVAC system and the environment. The heat exchangers generally include an arrangement of heat transfer tubes that are configured to receive a flow of working fluid. A fan may be used to direct an air flow across the heat transfer tubes to facilitate heat exchange between the working fluid circulating through the heat transfer tubes and the air flow. In some cases, an array of fins may be coupled to the heat transfer tubes to enhance a heat exchange rate between the working fluid and the air flow. Unfortunately, conventional heat exchangers may incur wear over time, which may result in performance degradation of the heat exchangers. Additionally, conventional heat exchangers may be heavy and cumbersome to move.

SUMMARY

The present disclosure relates to a heat exchanger that includes a tube configured to direct a working fluid therethrough. The heat exchanger also includes a fin disposed about the tube and having a louver, where the tube and the fin are made of a polymeric material.
The present disclosure also relates to a heat exchanger that includes a fin having an opening and a louver formed therein. The heat exchanger includes a tube positioned within the opening and configured to receive a flow of working fluid. The tube and the fin of the heat exchanger are made of a polymeric material.
The present disclosure also relates to a heat exchanger for a heating, ventilation, and/or air conditioning (HVAC) system. The heat exchanger includes a fin made of a first polymeric material, where the fin includes a louver formed therein. The heat exchanger also includes a tube made of a second polymeric material. The tube is coupled to the fin and is configured to receive a flow of working fluid.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of this disclosure may be better understood upon reading the following detailed description and upon reference to the drawings in which:

FIG. 1 is a perspective view of an embodiment of a building that may utilize a heating, ventilation, and/or air conditioning (HVAC) system in a commercial setting, in accordance with an aspect of the present disclosure;

FIG. 2 is a perspective view of an embodiment of a packaged HVAC unit, in accordance with an aspect of the present disclosure;

FIG. 3 is a perspective view of an embodiment of a split, residential HVAC system, in accordance with an aspect of the present disclosure;

FIG. 4 is a schematic diagram of an embodiment of a vapor compression system that may be used in an HVAC system, in accordance with an aspect of the present disclosure;

FIG. 5 is a perspective view of an embodiment of a polymeric heat exchanger for an HVAC system, in accordance with an aspect of the present disclosure;

FIG. 6 is a front perspective view of an embodiment of a heat transfer fin for a polymeric heat exchanger, in accordance with an aspect of the present disclosure;

FIG. 7 is a rear perspective view of an embodiment of a heat transfer fin for a polymeric heat exchanger, in accordance with an aspect of the present disclosure;

FIG. 8 is an axial view of an embodiment of a fin block having heat transfer fins, in accordance with an aspect of the present disclosure; and

FIG. 9 is a heat distribution diagram of a heat transfer fin for a polymeric heat exchanger, in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION

One or more specific embodiments of the present disclosure will be described below. These described embodiments are only examples of the presently disclosed techniques. Additionally, in an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
When introducing elements of various embodiments of the present disclosure, the articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.
As briefly discussed above, a heating, ventilation, and/or air conditioning (HVAC) system may include various heat exchangers, such as a condenser, an evaporator, and/or a hydronic coil, which may be utilized to facilitate heating or cooling of a space within a building, home, or other suitable structure. The heat exchangers are typically constructed from metallic materials including, for example, copper, aluminum, and/or brass. Unfortunately, such metallic heat exchangers may incur wear over time, which may result in performance degradation of the heat exchangers. Additionally, metallic heat exchangers may be heavy and cumbersome to move, thereby complicating installation and/or transportation of the heat exchangers.
It is now recognized that constructing heat exchangers from polymeric materials may mitigate or substantially eliminate performance degradation of the heat exchangers due to wear or other physical degradation. Accordingly, polymeric heat exchangers may have an increased operational life, as compared to an operational life of metallic heat exchangers. Therefore, polymeric heat exchangers may reduce overall maintenance costs and/or operating costs associated with the HVAC system. Moreover, it is now recognized that constructing heat exchangers from polymeric materials may reduce a weight of the heat exchangers, thus facilitating improved installation and/or transportation of the heat exchangers.
Accordingly, embodiments of the present disclosure are directed toward a polymeric heat exchanger that is formed from one or more polymeric materials. As an example, such polymeric materials may include plastic, high-density polyethylene, low-density polyethylene, poly vinyl chloride, high conductivity polymers, polypropylene, or various other polymeric materials. The polymeric heat exchanger includes one or more heat transfer tubes that are configured to receive a working fluid, such water, oil, refrigerant, or another suitable working fluid. The heat transfer tubes are placed in thermal communication with one or more heat transfer fins that are configured to facilitate heat transfer between the working fluid an ambient environment, such as the atmosphere. As discussed herein, in some embodiments, the heat transfer tubes and the heat transfer fins may be separate components that may be coupled to one another via a suitable adhesive, such as bonding glue, and/or via an interference fit. Particularly, the heat transfer tubes may extend through respective apertures or openings formed within the heat transfer fins, such that the heat transfer tubes may be coupled to the heat transfer fins along a perimeter of the apertures. Accordingly, the heat transfer tubes and the heat transfer fins may collectively form a heat exchanger assembly that defines a heat exchange area of the polymeric heat exchanger. In other embodiments, the heat transfer fins may be integrally formed with the heat transfer tubes. For example, the heat transfer fins and the heat transfer tubes may be formed as a single piece component via a suitable injection molding process or an additive manufacturing process. Accordingly, in such embodiments, the heat exchanger may be a single piece component that includes the heat transfer tubes and the heat transfer fins, amongst other components of the polymeric heat exchanger. These and other features will be described below with reference to the drawings.
Turning now to the drawings, FIG. 1 illustrates an embodiment of a heating, ventilation, and/or air conditioning (HVAC) system for environmental management that may employ one or more HVAC units. As used herein, an HVAC system includes any number of components configured to enable regulation of parameters related to climate characteristics, such as temperature, humidity, air flow, pressure, air quality, and so forth. For example, an “HVAC system” as used herein is defined as conventionally understood and as further described herein. Components or parts of an “HVAC system” may include, but are not limited to, all, some of, or individual parts such as a heat exchanger, a heater, an air flow control device, such as a fan, a sensor configured to detect a climate characteristic or operating parameter, a filter, a control device configured to regulate operation of an HVAC system component, a component configured to enable regulation of climate characteristics, or a combination thereof. An “HVAC system” is a system configured to provide such functions as heating, cooling, ventilation, dehumidification, pressurization, refrigeration, filtration, or any combination thereof. The embodiments described herein may be utilized in a variety of applications to control climate characteristics, such as residential, commercial, industrial, transportation, or other applications where climate control is desired.
In the illustrated embodiment, a building 10 is air conditioned by a system that includes an HVAC unit 12. The building 10 may be a commercial structure or a residential structure. As shown, the HVAC unit 12 is disposed on the roof of the building 10; however, the HVAC unit 12 may be located in other equipment rooms or areas adjacent the building 10. The HVAC unit 12 may be a single package unit containing other equipment, such as a blower, integrated air handler, and/or auxiliary heating unit. In other embodiments, the HVAC unit 12 may be part of a split HVAC system, such as the system shown in FIG. 3, which includes an outdoor HVAC unit 58 and an indoor HVAC unit 56.
The HVAC unit 12 is an air cooled device that implements a refrigeration cycle to provide conditioned air to the building 10. Specifically, the HVAC unit 12 may include one or more heat exchangers across which an air flow is passed to condition the air flow before the air flow is supplied to the building. In the illustrated embodiment, the HVAC unit 12 is a rooftop unit (RTU) that conditions a supply air stream, such as environmental air and/or a return air flow from the building 10. After the HVAC unit 12 conditions the air, the air is supplied to the building 10 via ductwork 14 extending throughout the building 10 from the HVAC unit 12. For example, the ductwork 14 may extend to various individual floors or other sections of the building 10. In certain embodiments, the HVAC unit 12 may be a heat pump that provides both heating and cooling to the building with one refrigeration circuit configured to operate in different modes. In other embodiments, the HVAC unit 12 may include one or more refrigeration circuits for cooling an air stream and a furnace for heating the air stream.
A control device 16, one type of which may be a thermostat, may be used to designate the temperature of the conditioned air. The control device 16 also may be used to control the flow of air through the ductwork 14. For example, the control device 16 may be used to regulate operation of one or more components of the HVAC unit 12 or other components, such as dampers and fans, within the building 10 that may control flow of air through and/or from the ductwork 14. In some embodiments, other devices may be included in the system, such as pressure and/or temperature transducers or switches that sense the temperatures and pressures of the supply air, return air, and so forth. Moreover, the control device 16 may include computer systems that are integrated with or separate from other building control or monitoring systems, and even systems that are remote from the building 10.
FIG. 2 is a perspective view of an embodiment of the HVAC unit 12. In the illustrated embodiment, the HVAC unit 12 is a single package unit that may include one or more independent refrigeration circuits and components that are tested, charged, wired, piped, and ready for installation. The HVAC unit 12 may provide a variety of heating and/or cooling functions, such as cooling only, heating only, cooling with electric heat, cooling with dehumidification, cooling with gas heat, or cooling with a heat pump. As described above, the HVAC unit 12 may directly cool and/or heat an air stream provided to the building 10 to condition a space in the building 10.
As shown in the illustrated embodiment of FIG. 2, a cabinet 24 encloses the HVAC unit 12 and provides structural support and protection to the internal components from environmental and other contaminants. In some embodiments, the cabinet 24 may be constructed of galvanized steel and insulated with aluminum foil faced insulation. Rails 26 may be joined to the bottom perimeter of the cabinet 24 and provide a foundation for the HVAC unit 12. In certain embodiments, the rails 26 may provide access for a forklift and/or overhead rigging to facilitate installation and/or removal of the HVAC unit 12. In some embodiments, the rails 26 may fit into “curbs” on the roof to enable the HVAC unit 12 to provide air to the ductwork 14 from the bottom of the HVAC unit 12 while blocking elements such as rain from leaking into the building 10.
The HVAC unit 12 includes heat exchangers 28 and 30 in fluid communication with one or more refrigeration circuits. Tubes within the heat exchangers 28 and 30 may circulate refrigerant, such as R-410A, through the heat exchangers 28 and 30. The tubes may be of various types, such as multichannel tubes, conventional copper or aluminum tubing, and so forth. Together, the heat exchangers 28 and 30 may implement a thermal cycle in which the refrigerant undergoes phase changes and/or temperature changes as it flows through the heat exchangers 28 and 30 to produce heated and/or cooled air. For example, the heat exchanger 28 may function as a condenser where heat is released from the refrigerant to ambient air, and the heat exchanger 30 may function as an evaporator where the refrigerant absorbs heat to cool an air stream. In other embodiments, the HVAC unit 12 may operate in a heat pump mode where the roles of the heat exchangers 28 and 30 may be reversed. That is, the heat exchanger 28 may function as an evaporator and the heat exchanger 30 may function as a condenser. In further embodiments, the HVAC unit 12 may include a furnace for heating the air stream that is supplied to the building 10. While the illustrated embodiment of FIG. 2 shows the HVAC unit 12 having two of the heat exchangers 28 and 30, in other embodiments, the HVAC unit 12 may include one heat exchanger or more than two heat exchangers.
The heat exchanger 30 is located within a compartment 31 that separates the heat exchanger 30 from the heat exchanger 28. Fans 32 draw air from the environment through the heat exchanger 28. Air may be heated and/or cooled as the air flows through the heat exchanger 28 before being released back to the environment surrounding the HVAC unit 12. A blower assembly 34, powered by a motor 36, draws air through the heat exchanger 30 to heat or cool the air. The heated or cooled air may be directed to the building 10 by the ductwork 14, which may be connected to the HVAC unit 12. Before flowing through the heat exchanger 30, the conditioned air flows through one or more filters 38 that may remove particulates and contaminants from the air. In certain embodiments, the filters 38 may be disposed on the air intake side of the heat exchanger 30 to prevent contaminants from contacting the heat exchanger 30.
The HVAC unit 12 also may include other equipment for implementing the thermal cycle. Compressors 42 increase the pressure and temperature of the refrigerant before the refrigerant enters the heat exchanger 28. The compressors 42 may be any suitable type of compressors, such as scroll compressors, rotary compressors, screw compressors, or reciprocating compressors. In some embodiments, the compressors 42 may include a pair of hermetic direct drive compressors arranged in a dual stage configuration 44. However, in other embodiments, any number of the compressors 42 may be provided to achieve various stages of heating and/or cooling. As may be appreciated, additional equipment and devices may be included in the HVAC unit 12, such as a solid-core filter drier, a drain pan, a disconnect switch, an economizer, pressure switches, phase monitors, and humidity sensors, among other things.
The HVAC unit 12 may receive power through a terminal block 46. For example, a high voltage power source may be connected to the terminal block 46 to power the equipment. The operation of the HVAC unit 12 may be governed or regulated by a control board 48. The control board 48 may include control circuitry connected to a thermostat, sensors, and alarms. One or more of these components may be referred to herein separately or collectively as the control device 16. The control circuitry may be configured to control operation of the equipment, provide alarms, and monitor safety switches. Wiring 49 may connect the control board 48 and the terminal block 46 to the equipment of the HVAC unit 12.
FIG. 3 illustrates a residential heating and cooling system 50, also in accordance with present techniques. The residential heating and cooling system 50 may provide heated and cooled air to a residential structure, as well as provide outside air for ventilation and provide improved indoor air quality (IAQ) through devices such as ultraviolet lights and air filters. In the illustrated embodiment, the residential heating and cooling system 50 is a split HVAC system. In general, a residence 52 conditioned by a split HVAC system may include refrigerant conduits 54 that operatively couple the indoor unit 56 to the outdoor unit 58. The indoor unit 56 may be positioned in a utility room, an attic, a basement, and so forth. The outdoor unit 58 is typically situated adjacent to a side of residence 52 and is covered by a shroud to protect the system components and to prevent leaves and other debris or contaminants from entering the unit. The refrigerant conduits 54 transfer refrigerant between the indoor unit 56 and the outdoor unit 58, typically transferring primarily liquid refrigerant in one direction and primarily vaporized refrigerant in an opposite direction.
When the system shown in FIG. 3 is operating as an air conditioner, a heat exchanger 60 in the outdoor unit 58 serves as a condenser for re-condensing vaporized refrigerant flowing from the indoor unit 56 to the outdoor unit 58 via one of the refrigerant conduits 54. In these applications, a heat exchanger 62 of the indoor unit 56 functions as an evaporator. Specifically, the heat exchanger 62 receives liquid refrigerant, which may be expanded by an expansion device, and evaporates the refrigerant before returning it to the outdoor unit 58.
The outdoor unit 58 draws environmental air through the heat exchanger 60 using a fan 64 and expels the air above the outdoor unit 58. When operating as an air conditioner, the air is heated by the heat exchanger 60 within the outdoor unit 58 and exits the unit at a temperature higher than it entered. The indoor unit 56 includes a blower or fan 66 that directs air through or across the indoor heat exchanger 62, where the air is cooled when the system is operating in air conditioning mode. Thereafter, the air is passed through ductwork 68 that directs the air to the residence 52. The overall system operates to maintain a desired temperature as set by a system controller. When the temperature sensed inside the residence 52 is higher than the set point on the thermostat, or a set point plus a small amount, the residential heating and cooling system 50 may become operative to refrigerate additional air for circulation through the residence 52. When the temperature reaches the set point, or a set point minus a small amount, the residential heating and cooling system 50 may stop the refrigeration cycle temporarily.
The residential heating and cooling system 50 may also operate as a heat pump. When operating as a heat pump, the roles of heat exchangers 60 and 62 are reversed. That is, the heat exchanger 60 of the outdoor unit 58 will serve as an evaporator to evaporate refrigerant and thereby cool air entering the outdoor unit 58 as the air passes over outdoor the heat exchanger 60. The indoor heat exchanger 62 will receive a stream of air blown over it and will heat the air by condensing the refrigerant.
In some embodiments, the indoor unit 56 may include a furnace system 70. For example, the indoor unit 56 may include the furnace system 70 when the residential heating and cooling system 50 is not configured to operate as a heat pump. The furnace system 70 may include a burner assembly and heat exchanger, among other components, inside the indoor unit 56. Fuel is provided to the burner assembly of the furnace system 70 where it is mixed with air and combusted to form combustion products. The combustion products may pass through tubes or piping in a heat exchanger, separate from heat exchanger 62, such that air directed by the blower 66 passes over the tubes or pipes and extracts heat from the combustion products. The heated air may then be routed from the furnace system 70 to the ductwork 68 for heating the residence 52.
FIG. 4 is an embodiment of a vapor compression system 72 that can be used in any of the systems described above. The vapor compression system 72 may circulate a refrigerant through a circuit starting with a compressor 74. The circuit may also include a condenser 76, an expansion valve(s) or device(s) 78, and an evaporator 80. The vapor compression system 72 may further include a control panel 82 that has an analog to digital (A/D) converter 84, a microprocessor 86, a non-volatile memory 88, and/or an interface board 90. The control panel 82 and its components may function to regulate operation of the vapor compression system 72 based on feedback from an operator, from sensors of the vapor compression system 72 that detect operating conditions, and so forth.
In some embodiments, the vapor compression system 72 may use one or more of a variable speed drive (VSDs) 92, a motor 94, the compressor 74, the condenser 76, the expansion valve or device 78, and/or the evaporator 80. The motor 94 may drive the compressor 74 and may be powered by the variable speed drive (VSD) 92. The VSD 92 receives alternating current (AC) power having a particular fixed line voltage and fixed line frequency from an AC power source, and provides power having a variable voltage and frequency to the motor 94. In other embodiments, the motor 94 may be powered directly from an AC or direct current (DC) power source. The motor 94 may include any type of electric motor that can be powered by a VSD or directly from an AC or DC power source, such as a switched reluctance motor, an induction motor, an electronically commutated permanent magnet motor, or another suitable motor.
The compressor 74 compresses a refrigerant vapor and delivers the vapor to the condenser 76 through a discharge passage. In some embodiments, the compressor 74 may be a centrifugal compressor. The refrigerant vapor delivered by the compressor 74 to the condenser 76 may transfer heat to a fluid passing across the condenser 76, such as ambient or environmental air 96. The refrigerant vapor may condense to a refrigerant liquid in the condenser 76 as a result of thermal heat transfer with the environmental air 96. The liquid refrigerant from the condenser 76 may flow through the expansion device 78 to the evaporator 80.
The liquid refrigerant delivered to the evaporator 80 may absorb heat from another air stream, such as a supply air stream 98 provided to the building 10 or the residence 52. For example, the supply air stream 98 may include ambient or environmental air, return air from a building, or a combination of the two. The liquid refrigerant in the evaporator 80 may undergo a phase change from the liquid refrigerant to a refrigerant vapor. In this manner, the evaporator 80 may reduce the temperature of the supply air stream 98 via thermal heat transfer with the refrigerant. Thereafter, the vapor refrigerant exits the evaporator 80 and returns to the compressor 74 by a suction line to complete the cycle.
In some embodiments, the vapor compression system 72 may further include a reheat coil in addition to the evaporator 80. For example, the reheat coil may be positioned downstream of the evaporator relative to the supply air stream 98 and may reheat the supply air stream 98 when the supply air stream 98 is overcooled to remove humidity from the supply air stream 98 before the supply air stream 98 is directed to the building 10 or the residence 52.
It should be appreciated that any of the features described herein may be incorporated with the HVAC unit 12, the residential heating and cooling system 50, or other HVAC systems. Additionally, while the features disclosed herein are described in the context of embodiments that directly heat and cool a supply air stream provided to a building or other load, embodiments of the present disclosure may be applicable to other HVAC systems as well. For example, the features described herein may be applied to mechanical cooling systems, free cooling systems, chiller systems, or other heat pump or refrigeration applications.
FIG. 5 is a perspective view of an embodiment of a polymeric heat exchanger 100 that may be included in the HVAC unit 12, the residential heating and cooling system 50, a rooftop unit, a terminal unit, or any other HVAC system that utilizes heat exchangers. It should be appreciated that, in certain embodiments, the polymeric heat exchanger 100 may be included in other heat transfer applications such as, for example, automotive heating and cooling systems or heating and cooling systems for electronic devices. In any case, as shown in the illustrated embodiment, the polymeric heat exchanger 100 includes a plurality of heat transfer fins 102 that are positioned adjacent to one another to define a fin block 104 of the polymeric heat exchanger 100. The polymeric heat exchanger 100 may include a plurality of heat transfer tubes 106 that are configured to extend through respective apertures 110, as shown in FIG. 6, formed within each of the heat transfer fins 102. The heat transfer tubes 106 may be fluidly coupled to one another via a plurality of elbows 114 to form a serpentine fluid flow path 116 that extends between an inlet 118 and an outlet 120 of the polymeric heat exchanger 100. Accordingly, the heat transfer fins 102, the heat transfer tubes 106, and the elbows 114 may collectively define a heat exchanger assembly 122 of the polymeric heat exchanger 100.
The fluid flow path 116 may be configured to receive a flow of working fluid from a suitable fluid source to place the working fluid in thermal communication with the heat exchanger assembly 122. For example, in some embodiments, the fluid flow path 116 may be configured to receive a heated working fluid from a boiler or to receive a chilled working fluid from a chiller. In such embodiments, the working fluid may include water, oil, or another suitable working fluid. In other embodiments, the working fluid may include a flow of refrigerant provided via a vapor compression system, such as the vapor compression system 72. In any case, the polymeric heat exchanger 100 may facilitate heat transfer between the working fluid circulating through the fluid flow path 116 and an air flow 126 that may be directed across heat transfer tubes 106 and the heat transfer fins 102. For example, a fan or other suitable flow generating device may be configured to generate the air flow 126 and to force the air flow 126 in a downstream direction 128 across the heat transfer tubes 106 and the heat transfer fins 102 from an upstream end portion 130 of the heat transfer fins 102 to a downstream end portion 132 of the heat transfer fins 102. However, it should be understood that, in other embodiments, another suitable heat transfer fluid may be directed across the heat transfer tubes 106 and the heat transfer fins 102 in addition to, or in lieu of, the air flow 126. Indeed, in some embodiments, polymeric heat exchanger 100 may be utilized in a variety of heat transfer applications to facilitate heat transfer from one fluid to another fluid.
In some embodiments, the heat transfer fins 102, the heat transfer tubes 106, the elbows 114, or any combination thereof, may be formed from one or more polymeric materials. As discussed above, such polymeric materials may include, but are not limited to, plastic, high-density polyethylene, low-density polyethylene, poly vinyl chloride, high conductivity polymers, polypropylene, or various other polymeric materials. Accordingly, the heat transfer fins 102, the heat transfer tubes 106, and/or the elbows 114 may be substantially inhibited from or resistant to corrosion, which may increase an operational life of the polymeric heat exchanger 100. As such, the polymeric heat exchanger 100 may reduce overall maintenance costs associated with an HVAC system having the polymeric heat exchanger 100, as compared to an HVAC system having conventional metallic heat exchangers. Moreover, constructing the polymeric heat exchanger 100 from polymeric materials may reduce an overall assembly cost of the polymeric heat exchanger 100. Indeed, as discussed in detail herein, the heat transfer fins 102, the heat transfer tubes 106, and/or the elbows 114 may be produced relatively inexpensively via, for example, an injection molding process, an extrusion process, or an additive manufacturing process. It should be appreciated that, in some embodiments, the heat transfer tubes 106 and the elbows 114 may be formed from a first polymeric material, while the heat transfer fins 102 are formed from a second polymeric material that is different from the first polymeric material. In other embodiments, the heat transfer tubes 106, the elbows 114, and the heat transfer fins 102 may each be formed from different polymeric materials or from the same polymeric material.
FIG. 6 is a front perspective view of an embodiment of a portion of a heat transfer fin 136, such as one of the heat transfer fins 102 of the polymeric heat exchanger 100. FIG. 7 is a rear perspective view of an embodiment of the portion of the heat transfer fin 136. FIGS. 6 and 7 will be discussed concurrently below. The heat transfer fin 136 includes a body panel 138 having the apertures 110, also referred to herein as openings, formed therein. The apertures 110 may include a cross-sectional profile that is substantially similar to a cross-sectional profile of the heat transfer tubes 106. As an example, in some embodiments, the apertures 110 and the heat transfer tubes 106 may each include a generally oval or oblong cross-sectional profile. In some embodiments, respective surface areas of the heat transfer tubes 106 may be increased by forming the heat transfer tubes 106 to include oblong cross-sectional profiles. Such a tube configuration of the heat transfer tubes 106 may therefore increase interaction between the air flow 126 and the heat transfer tubes 106, and thus, may enhance a heat transfer rate between the air flow 126 and the working fluid circulating through the fluid flow path 116. Moreover, in some embodiments, forming the heat transfer tubes 106 to include a generally oblong cross-sectional profile may reduce fluidic restriction across the polymeric heat exchanger 100, as compared to heat transfer tubes including, for example, a circular cross-sectional profile. Accordingly, the heat transfer tubes 106 discussed herein may increase an operational efficiency of a fan configured to direct the air flow 126 across the polymeric heat exchanger 100 from the upstream end portion 130 to the downstream end portion 132 of the polymeric heat exchanger 100. However, it should be appreciate that, in other embodiments, the apertures 110 and the heat transfer tubes 106 may include any other suitable cross-sectional profiles that are complementary to one another.
In some embodiments, each of the heat transfer tubes 106 may be configured to extend through a respective one of the apertures 110. Multiple heat transfer fins 102 may be engaged with the heat transfer tubes 106 in a stacked manner to form the fin block 104. In some embodiments, the heat transfer tubes 106 may include exterior dimensions that are marginally greater than interior dimensions of the corresponding apertures 110. Accordingly, an interference fit may be generated between the heat transfer tubes 106 extending through the apertures 110 that may facilitate coupling the heat transfer fins 102 to the heat transfer tubes 106. That is, in such embodiments, interior surfaces of the apertures 110 may be configured to apply and maintain a compressive force on the exterior surfaces of the heat transfer tubes 106. In certain embodiments, an adhesive, such as bonding glue, may be used to couple the heat transfer fins 102 to the heat transfer tubes 106 in addition to, or in lieu of such an interference fit.
In some embodiments, the heat transfer fin 136 may include respective flanges 140 that extend about a perimeter of one or more of the apertures 110. The flanges 140 may extend generally orthogonal to the body panel 138 from a first surface 144 or a first side of the body panel 138, from a second surface 146 or a second side of the body panel 138, or both. Indeed, in some embodiments, the flanges 140 may extend bi-directionally from the body panel 138 in directions that extend generally orthogonal or cross-wise to the body panel 138. The heat transfer tubes 106 may be configured to engage with the flanges 140 in a similar manner as the engagement between the heat transfer tubes 106 and the inner perimeter of the apertures 110 discussed above. That is, the heat transfer tubes 106 may be coupled to an inner perimeter of the flanges 140 via an interference fit or via a suitable adhesive.
In some embodiments, when the heat transfer fins 102 are stacked in the fin block 104, the flanges 140 of neighboring heat transfer fins 102 may be configured to engage with one another. Accordingly, the flanges 140 may form continuous tunnels that extend along a length 150, as shown in FIG. 5, of the fin block 104 through a corresponding set of the apertures 110. To better illustrate and to facilitate the following discussion, FIG. 8 is an axial view of an embodiment of the fin block 104. As shown in the illustrated embodiment, when arranged in the fin block 104, the flanges 140 of adjacent heat transfer fins 102 may engage with one another to define a plurality of tunnels 152 that extend along the length 150 of the fin block 104. The heat transfer tubes 106 may each be configured to extend through a corresponding one of the tunnels 152. In some embodiments, each of the tunnels 152 may form a substantially fluid tight flow path that is defined by respective interior surfaces of the flanges 140 and that extends between a first lateral end 156 and a second lateral end 158 of the fin block 104. As noted above, exterior surfaces of the heat transfer tubes 106 may be configured to abut the interior surfaces of the flanges 140. Accordingly, when the heat transfer fins 102 are positioned to form the tunnels 152, the flanges 140 may cover substantially all of the exterior surfaces of the heat transfer tubes 106 positioned between the first and second lateral ends 156, 158 of the fin block 104. In some embodiments, this configuration may provide additional structural rigidity to the heat transfer tubes 106 and the entire polymeric heat exchanger 100. In particular, the flanges 140 may reduce or substantially mitigate expansion or swelling of the heat transfer tubes 106 when a pressure within the fluid flow path 116 is elevated. It should be understood that, in certain embodiments, a gap may remain between adjacent flanges 140 when the heat transfer fins 102 are arrayed in the fin block 104.
The subsequent discussion continues with reference to FIGS. 6 and 7. In some embodiments, the body panel 138 may include a plurality of louvers 160 that extend outwardly from the first surface 144 of the body panel 138, that extend outwardly from the second surface 146 of the body panel 138, or both. For example, the louvers 160 may include a set of first louvers 162 that extend outwardly from the first surface 144 of the body panel 138. Accordingly, first louvers 162 may form respective first fluid passages 164 that extend from the first surface 144 to the second surface 146 of the heat transfer fin 136. The first fluid passages 164 may initiate at respective louver openings that are formed between the first surface 144 and corresponding ones of the first louvers 162.
The louvers 160 may include a set of second louvers 168 that extend outwardly from the second surface 146 of the body panel 138. Similar to the first louvers 162, the second louvers 168 may form respective second fluid passages 170 that extend from the second surface 146 to the first surface 144 of the body panel 138. The second fluid passages 170 may initiate at respective louver openings that are formed between the second surface 146 and corresponding ones of the second louvers 168. As one of skill in the art will appreciate, the first and second louvers 162, 168 may facilitate fluid flow between the first and second surfaces 144, 146 of the body panel 138 which, in some embodiments, may facilitate and/or improve heat transfer between the air flow 126 and the heat transfer fin 136.
In some embodiments, the louvers 160 may be configured to generate fluidic turbulences within the air flow 126 as the air flow 126 is directed across the heat transfer fins 102 in the downstream direction 128. As such, the louvers 160 may reduce or substantially eliminate the generation of relatively large wake regions that may be formed downstream of each of the heat transfer tubes 106. Indeed, such wake regions may typically be formed during laminar air flow conditions across the heat transfer tubes 106. Accordingly, by reducing or mitigating such wake regions, the louvers 160 may increase an effective surface area of the heat transfer tubes 106 with which the air flow 126 interacts. As such, the louvers 160 may facilitate heat transfer between the air flow 126 and the working fluid circulating through the fluid flow path 116.
In some embodiments, the louvers 160 may be arranged in various louver groups 180 along the heat transfer fin 136. In certain embodiments, certain of the louver groups 180 may be oriented toward particular apertures 110, while other louver groups 180 are oriented away from particular apertures 110. For example, as shown in the illustrated embodiment of FIG. 6, the louver groups 180 may include a first louver group 182 that includes four of the first louvers 162. Each of the first louvers 162 within the first louver group 182 may be oriented such that the respective louver openings of the first fluid passages 164 of these first louvers 162 are positioned adjacent to a perimeter of one of the apertures 110, referred to herein as a pilot aperture 184. As shown in the illustrated embodiment of FIG. 7, the louver groups 180 may also include a second louver group 190 that includes four of the second louvers 168. Each of the second louvers 168 within the second louver group 190 may be oriented such that respective louver openings of the second fluid passages 170 of these second louvers 168 are positioned distal to the perimeter of the pilot aperture 184.
As noted above, in some embodiments, the heat transfer fins 102, the heat transfer tubes 106, and/or the elbows 114 may be formed as individual components from various polymeric materials via, for example, an injection molding process, an extrusion process, or an additive manufacturing process, also referred to as a three dimensional (3D) printing process. Accordingly, the heat transfer fins 102, the heat transfer tubes 106, and the elbows 114 may be assembled to collectively form the heat exchanger assembly 122. In other embodiments, the heat transfer fins 102, the heat transfer tubes 106, the elbows 114, or any combination thereof, may be integrally formed as a single piece component. That is, in some embodiments, the heat exchanger assembly 122 may be manufactured as a single piece component using, for example, an additive manufacturing process.
In some embodiments, the polymeric material used to the construct the polymeric heat exchanger 100 may be selected to enhance a heat transfer ability of the polymeric heat exchanger 100. In other words, the polymeric material may be tailored to facilitate heat transfer between the air flow 126 and a working fluid circulating through the fluid flow path 116. As a non-limiting example, such a polymeric material may include high density polyethylene having a thermal conductivity value of at least 10 Watts per meter-Kelvin. However, in other embodiments, the polymeric material used to construct the polymeric heat exchanger 100 may include any other suitable polymeric material having a thermal conductivity value that is less than or greater than 10 Watts per meter-Kelvin. FIG. 9 is an embodiment of a heat distribution diagram 200 illustrating a heat distribution across the heat transfer fin 136 for a particular polymeric material.
As set forth above, embodiments of the present disclosure may provide one or more technical effects useful for substantially eliminating performance degradation of heat exchangers due to corrosion or other wear. Indeed, the polymeric heat exchanger 100 of the present disclosure may be constructed of one or more polymeric materials that are substantially resistant to corrosion, such that the polymeric heat exchanger 100 may have an increased operational life, as compared to an operational life of metallic heat exchangers. Therefore, polymeric heat exchanger 100 may reduce overall maintenance costs and/or operating costs associated with an HVAC system. Moreover, constructing the polymeric heat exchanger 100 from polymeric materials may reduce a weight of the polymeric heat exchanger 100, as compared to a weight of metallic heat exchangers, thus facilitating installation and/or transportation of the heat exchangers. The technical effects and technical problems in the specification are examples and are not limiting. It should be noted that the embodiments described in the specification may have other technical effects and can solve other technical problems.
While only certain features and embodiments of the present disclosure have been illustrated and described, many modifications and changes may occur to those skilled in the art, such as variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, such as temperatures and pressures, mounting arrangements, use of materials, colors, orientations, and so forth, without materially departing from the novel teachings and advantages of the subject matter recited in the claims. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the present disclosure. Furthermore, in an effort to provide a concise description of the exemplary embodiments, all features of an actual implementation may not have been described, such as those unrelated to the presently contemplated best mode of carrying out the present disclosure, or those unrelated to enabling the claimed embodiments. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation specific decisions may be made. Such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, without undue experimentation.

Claims

1. A heat exchanger, comprising:

a tube configured to direct a working fluid therethrough; and

a fin disposed about the tube and having a louver, wherein the tube and the fin are made of a polymeric material.

2. The heat exchanger of claim 1, wherein the tube and the fin are integrally formed as a single piece component.

3. The heat exchanger of claim 1, wherein the polymeric material is a high density polyethylene.

4. The heat exchanger of claim 1, wherein the polymeric material has a thermal conductivity value of at least 10 Watts per meter-Kelvin.

5. The heat exchanger of claim 1, wherein the tube has an oblong cross-sectional profile.

6. The heat exchanger of claim 1, wherein the fin includes an opening, and the tube is disposed within the opening and is secured within the opening via an interference fit.

7. The heat exchanger of claim 6, wherein the fin includes a flange extending about a perimeter of the opening, and the flange is engaged with the tube via the interference fit.

8. The heat exchanger of claim 1, wherein the louver is a first louver, and the fin includes a second louver, wherein the first louver extends from a first side of the fin, and the second louver extends from a second side of the fin opposite to the first side.

9. A heat exchanger, comprising:

a fin having an opening and a louver formed therein; and

a tube positioned within the opening and configured to receive a flow of working fluid, wherein the tube and the fin are made of a polymeric material.

10. The heat exchanger of claim 9, wherein the opening has an oblong cross-sectional profile that is configured to engage with the tube via an interference fit.

11. The heat exchanger of claim 9, wherein an adhesive is configured to couple the tube to a perimeter of the opening.

12. The heat exchanger of claim 9, wherein the fin is a first fin, and the heat exchanger includes a second fin positioned adjacent to the first fin and having an additional opening, wherein the tube is positioned within the additional opening.

13. The heat exchanger of claim 12, comprising a first flange extending about a perimeter of the opening and a second flange extending about a perimeter of the additional opening, wherein the first flange is configured to abut the second flange to form a tunnel extending through the first fin and the second fin in an assembled configuration of the heat exchanger.

14. The heat exchanger of claim 13, wherein the tunnel includes an interior surface, and an exterior surface of the tube is configured to abut the interior surface.

15. The heat exchanger of claim 9, wherein the louver forms a fluid flow path that extends from a first surface of the fin to a second surface of the fin disposed opposite to the first surface.

16. The heat exchanger of claim 9, wherein the louver is one of a plurality of louvers arrayed in a louver group, wherein each louver in the louver group forms a respective fluid flow path through the fin from a first surface of the fin to a second surface of the fin, opposite to the first surface, wherein the fluid flow paths include louver openings defined between respective ones of the louvers and the first surface, and wherein each of the louver openings is oriented toward a perimeter of the opening.

17. The heat exchanger of claim 9, wherein the tube is configured to contain and facilitate flow of water as the working fluid.

18. The heat exchanger of claim 9, wherein the polymeric material is a high density polyethylene having a thermal conductivity value of at least 10 Watts per meter-Kelvin.

19. A heat exchanger for a heating, ventilation, and/or air conditioning (HVAC) system, comprising:

a fin made of a first polymeric material and having a louver formed therein; and

a tube made of a second polymeric material and coupled to the fin, wherein the tube is configured to receive a flow of working fluid.

20. The heat exchanger of claim 19, wherein the first polymeric material is different from the second polymeric material.

21. The heat exchanger of claim 19, wherein the first polymeric material and the second polymeric material are a high density polyethylene.

22. The heat exchanger of claim 19, wherein the louver is formed integrally with the fin via an injection molding process or an additive manufacturing process.

23. The heat exchanger of claim 19, wherein the fin includes an opening, and the tube extends through the opening.

24. The heat exchanger of claim 23, wherein the fin includes a flange that extends about a perimeter of the opening and that extends bi-directionally from the fin in directions generally orthogonal to the fin.

25. The heat exchanger of claim 24, wherein the tube is coupled to an interior surface of the flange via an interference fit, via an adhesive, or both.

26. The heat exchanger of claim 19, wherein the tube and the fin are integrally formed as a one piece structure.