FIELD OF DISCLOSURE
The present subject matter relates to an apparatus, assembly, and method for exchanging heat.
BACKGROUND
In some industrial, commercial, or residential settings, there may be pipes, ducts or other conduits that transport a hot fluid. The hot fluid may be a hot exhaust gas from a furnace, a hot water heater, a component used in an industrial process, or the like. It may be advantageous in some instances to use a heat exchanger to capture heat from the hot fluid and transfer it to a cool fluid. The cool fluid may be cool air to be heated for environmental or industrial process purposes, water that must be heated for use as tap water or for use in an industrial process, etc. Generally speaking, existing heat exchangers are coil-shaped to maximize the surface area available for heat exchange and are disposed inside the hot fluid conduit. The heat exchanger is connected to a fluid circuit that supplies a heat exchange fluid that flows through the heat exchanger to capture heat from the hot fluid traversing through the conduit.
Known heat exchangers can be complex and time consuming to fabricate and install. Also, such heat exchangers have inlet and outlet structures forming flow paths that necessarily pass through the walls of the hot fluid conduit, requiring sealing component(s) that can fail resulting in the escape of hot fluid from the conduit. This escape can be unacceptable given the presence of toxic substances therein, such as carbon monoxide in the case of combusted flue gas. Still further, a failure in a weld, for example, in the heat exchanger requires the heat exchanger to be removed from the hot fluid conduit, or at least exposed inside the conduit, so that access can be had thereto for repair. As should be evident, gaining such access is typically a difficult and time consuming process.
SUMMARY
According to one aspect, a heat exchanger module includes a curved inner surface adapted to enclose at least a portion of an outside surface of a conduit. The heat exchanger module further includes a curved outer surface at least partially enclosing the curved inner surface. The heat exchanger module further includes a first port adapted to receive heat exchanger fluid and a second port spaced from the first port and adapted to exhaust heat exchanger fluid. The heat exchanger module further comprises a plurality of curved flow guides disposed between the curved inner surface and the curved outer surface. The curved flow guides are disposed between the first and second ports and they define a closed flow path between the first port and the second port.
According to another aspect a heat exchanger includes a plurality of substantially identical and separate heat exchanger modules. Each heat exchanger module includes at least one surface defining at least one thermally conductive closed flow path extending between an inlet port and an outlet port. The at least one thermally conductive flow path has a serpentine shape in a first dimension and has a shape in a second dimension adapted to conform at least substantially to a particular shape. The heat exchanger further comprises connection elements adapted to couple the plurality of heat exchanger modules to one another in fluid communication. The connection elements are further adapted to couple the plurality of heat exchanger modules about and in heat transfer relationship with an outer surface of a conduit of the particular shape.
According to yet another aspect, a method of exchanging heat includes arranging a first heat exchanger module around an outside surface of a conduit. The method further includes arranging a second heat exchanger module adjacent the first heat exchanger module to form a first band that substantially surrounds the outside surface of a conduit. The method further includes arranging a second band substantially identical to the first band along a length of the conduit.
Other aspects and advantages will become apparent upon consideration of the following detailed description and the attached drawings wherein like numerals designate like structures throughout the specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of a heat exchanger comprised of a plurality of heat exchanger modules arranged around an outside surface of a conduit that transports a hot fluid, with other devices shown in schematic view;
FIG. 1A is an enlarged view of two adjacent ports of two adjacent heat exchanger modules, wherein the two ports are connected by a connection member;
FIG. 1B is an enlarged view of two adjacent ports of two adjacent heat exchanger modules, wherein the two ports are adapted to interfit with one another;
FIG. 2 is an isometric view of a heat exchanger module of the heat exchanger;
FIG. 2A is a plan view of the heat exchanger module;
FIG. 2B is a side elevational view of the heat exchanger module;
FIG. 2C is a front elevational view of the heat exchanger module with flow guides of the heat exchanger module shown in dotted line through an inner curved plate of the heat exchanger module, wherein the curved heat exchanger module is shown in flattened form for clarity;
FIG. 3 is an enlarged plan view of one of the flow guides of the heat exchanger module;
FIG. 3A is a front elevational view of the flow guide of the heat exchanger module;
FIG. 4 is a plan view of two adjacent flow guides of the heat exchanger module;
FIG. 5 is a front elevational view of a second embodiment of the heat exchanger module with flow guides and a vertical spine for creating two flow paths shown in dotted line through an inner curved plate of the second embodiment of the heat exchanger module, wherein the curved heat exchanger module is shown in flattened form for clarity;
FIG. 5A is an isometric view of the second embodiment of a heat exchanger module of the heat exchanger;
FIG. 5B is a side elevational view of the second embodiment of the heat exchanger module;
FIG. 5C is a plan view of the second embodiment of the heat exchanger module;
FIG. 6 is an enlarged plan view of one of the flow guides of the second embodiment of the heat exchanger module;
FIG. 7 is a plan view of two adjacent flow guides of the second embodiment of the heat exchanger module;
FIG. 8 is a plan view of a vertical spine of the second embodiment of the heat exchanger module;
FIG. 8A is a side elevational view of the vertical spine of the second embodiment of the heat exchanger module;
FIG. 9 is an isometric view of a tube-like third embodiment of the heat exchanger module;
FIG. 10 is a flowchart of a method of exchanging heat by arranging heat exchanger modules around an outside surface of a conduit for hot fluid;
FIG. 11 is an isometric view of a heat exchanger module arranged around an outside surface of a conduit for hot fluid;
FIG. 12 is an isometric view of the heat exchanger module of FIG. 11 disposed opposite from another heat exchanger module to form a first band that substantially surrounds the outside surface of the conduit;
FIG. 13 is an isometric view of a plurality of bands, each made of two heat exchanger modules disposed opposite from one another, with a port of one heat exchanger module being connected by a connecting member to a port of a downstream or upstream heat exchanger module; and
FIG. 14 is an isometric view of the bands of heat exchanger modules wrapped in insulation, with other devices shown in schematic view.
DETAILED DESCRIPTION
FIG. 1 shows a thermal source 44 such as a furnace in fluid communication with a conduit 48 that transports hot fluid 52 from the thermal source 44 along a primary fluid circuit 56. The conduit 48 has an outside surface 58, as further shown in FIG. 1. The hot fluid 52 may be a hot gas or a hot liquid. A heat exchanger 60 that is adapted to extend about the conduit 48 is comprised of a plurality of bands 64 arranged along a length of the conduit 48, with each band 64 preferably including at least one, and more preferably at least two substantially or completely identical and separate heat exchanger modules 68 disposed opposite from one another and at least partially surrounding the conduit 48, as further shown in FIG. 1. The heat exchanger modules 68 of the heat exchanger 60 are in fluid communication with one another, together with a pump 72 and one or more additional devices, such as a conventional heat exchanger 76, to form a secondary fluid circuit 80, as shown in FIG. 1. As the pump 72 supplies a heat exchanger fluid under pressure through the secondary fluid circuit 80, heat exchanger fluid traversing through the heat exchanger modules 68 absorbs heat from the conduit 48. The heat in the heat exchanger fluid is preferably transferred to a thermal destination via another device, fluid, environment (ambient or another), or the like. In the illustrated embodiment, the conventional heat exchanger 76 transfers heat from the heat exchanger fluid of the secondary fluid circuit 80 to a fluid flowing through a tertiary fluid circuit 84 so that a thermal destination 88 that is connected to the tertiary fluid circuit 84 can receive heat. The thermal destination 88 may be, for example, a water tank that stores water to be heated. In this way, the heat exchanger 60 provides an improvement in energy efficiency by capturing the heat of the fluid flowing through the conduit 48 that would otherwise be lost.
One embodiment of the heat exchanger modules 68 of the heat exchanger 60 is shown in greater detail in FIG. 2, it being assumed that the wall of the conduit 48 is thermally conductive and has a circular cross section that is substantially constant for at least a portion of the length of the conduit. The heat exchanger module 68 illustrated in FIG. 2 includes a curved inner plate 92 having a semi-circular shape in cross section and a curved outer plate 96 having a semi-circular shape in cross section. The curved inner plate 92 has a curved inner surface 98 that forms a concave face of the module 68 that is adapted to enclose at least a portion of the outside surface 58 of the conduit 48. Preferably, the radius of curvature of the curved inner surface 98 is at least substantially equal to the radius of curvature of the outside surface 58 of the conduit 48. Moreover, the curved outer plate 96 has a curved outer surface 99 that at least partially encloses the curved inner surface 98. In the illustrated embodiment the curved outer plate 96 has a larger radius of curvature than the curved inner plate 92, thereby creating a curved space 100 between the curved inner and outer plates 92 and 96, as shown in FIG. 2A. Referring again to FIG. 2, the heat exchanger module 68 further includes first and second elongate end plates 104a, 104b, respectively. As shown in FIG. 2, the first end plate 104a extends between the curved inner plate 92 and the curved outer plate 96 at one circumferential end of the heat exchanger module 68. The second end plate 104b extends between the curved inner plate 92 and the curved outer plate 96 at the other circumferential end of the heat exchanger module 68.
As further shown in FIG. 2, the heat exchanger module 68 includes a curved end member 108 disposed atop the curved inner plate 92 and the curved outer plate 96 at one axial end of the module 68. The curved end member 108 has an upper wall 112 that extends from the curved inner plate 92 to the curved outer plate 96 radially along the heat exchanger module 68, as shown in FIG. 2B. The curved end member 108 thus comprises a top cover of the heat exchanger module 68 when the heat exchanger module is oriented as shown in FIG. 2B. The curved end member 108 further comprises a first port or opening 116 adapted to receive or exhaust a heat exchanger fluid such as thermal oil or water, either alone or in combination with one or more of ethylene glycol, ethyl alcohol, propylene glycol, glycerol, or the like together with one or more known anti-corrosion agents, flowing through the heat exchanger 60. As further shown in FIG. 2, the heat exchanger module 68 further includes a second curved end member 120 disposed at bottom edges of the curved inner plate 92 and the curved outer plate 96. The curved end member 120 has a lower wall 124 that radially extends from the curved inner plate 92 to the curved outer plate 96 along the heat exchange module 68, as shown in FIG. 2B. In this way, the curved end member 120 comprises a bottom cover of the heat exchanger module 68, when the module 68 is oriented as shown in FIG. 2B. The curved end member 108 further comprises a second port or opening 128 adapted to receive or exhaust a heat exchanger fluid flowing through the heat exchanger 60. As shown in FIG. 2, the port 116 is spaced from the port 128. In this way, the space 100 is enclosed by the curved inner plate 92, curved outer plate 96, the end plates 104, and the curved end members 108, 120. Two or more of the elements 92, 96, 104, 108, 120 may be integral with one another and/or such elements may be secured together in any suitable fashion, such as by welding, brazing, one or more fasteners, or the like.
As further shown in the embodiment of FIG. 2C, the heat exchanger module 68 further comprises a plurality of arcuate or curved flow guides 132 disposed between the curved inner plate 92 and the curved outer plate 96. The flow guides 132 are disposed at spaced axial locations between the port 116 and the port 128 and define a closed flow path between the port 116 and the port 128. Preferably, the flow guides are disposed at equidistant axial locations, although this need not be the case. As shown in FIG. 3, each flow guide 132 has an arcuate length short of a semi-circle such that a gap 136 is created at one end of the flow guide 132. The flow guides 132 are arranged within the module 68 such that the gap 136 is disposed at alternate circumferential ends of the module 68 for successive flow guides 132, as shown in FIG. 4. The alternating nature of the gaps 136 of the flow guides 132 creates a back-and-forth or serpentine flow path 134 for the heat exchanger fluid, as shown in FIG. 2C. As shown in FIG. 3A, the curved flow guides 132 are thin plates having a flat surface 138 that is disposed substantially perpendicularly to the curved inner plate 92 and the curved outer plate 96, as shown in FIG. 2C. To fit within the space 100, the flat surface 138 of the curved flow guide 132 has a width substantially identical to a distance between the curved inner plate 92 and the curved outer plate 96. The flow guides 132 are integral with or are secured to and/or sealed against an outer surface 139 of the curved inner plate 92 (shown in FIG. 2A) and to an inner surface 140 of the curved outer plate 96 (shown in FIG. 2A) in any suitable fashion, such as by one or more of welding, brazing, compression sealing, fasteners, adhesive, or the like.
In operation, the module 68 (and, optionally, other modules 68 fluidically interconnected therewith as noted in greater detail hereinafter) are secured to the outer surface 58 of the conduit 48 such that the inner surface 98 is in intimate thermal contact with the outer surface 58 of the conduit 48, as shown in FIG. 1. The module(s) 68 are maintained in place on the conduit 48 by any suitable means, such as by straps, bands, clamps, cable ties, or the like. Thus, as shown in the embodiment of FIG. 2C, the heat exchanger fluid enters the heat exchanger module 68 at the port 128 and flows to the right under pressure toward a gap 136 of a first flow guide 132. The gap 136 is disposed at a circumferential end of the first flow guide 132 shown on the right side of FIG. 2C. The heat exchanger fluid flows through the gap 136 and flows leftward toward a gap 136 of a second flow guide 132. Furthermore, the heat exchanger fluid flows through the gap 136 of the second guide 132 and flows rightward toward a gap 136 of the third flow guide 132, as shown in FIG. 2C. The heat exchanger fluid zig-zags (or flows in a serpentine, looping, winding, or twisting manner) in this manner through a back-and-forth or serpentine flow path 134 formed by the twenty-one (21) flow guides 132 that are spaced between the curved end member 120 and the curved end member 108, as further shown in FIG. 2C. As should be evident, any appropriate number of flow guides 132 can be used within the heat exchanger module 68 to create the flow path 134.
As the heat exchanger fluid is traversing the flow path 134 defined by the flow guides 132, the heat exchanger fluid absorbs heat from the conduit 48 and the temperature of the heat exchanger fluid rises as a result. As further shown in FIG. 2C, the heat exchanger fluid flows through a gap 136 at the rightward end of the uppermost flow guide 132, flows leftward toward the port 116, and exits the heat exchanger module 68 at the port 116. In this way, heat is transferred from the hot fluid 52 to the conduit 48 at least by convection, from the conduit 48 to the curved inner plate 92 at least by conduction (the conduit 48 and the curved inner plate 92 preferably intimately contact one another over substantially all of the surface area of the curved inner plate 92), and from the curved inner plate 92 to the heat exchanger fluid at least by convection as the heat exchanger fluid is traversing the flow path 134 from the port 128 to the port 116.
In the illustrated embodiment of FIG. 2C, the port 128 is used as an inlet and the port 116 is used as an outlet. In some embodiments, the port 128 can be used as an outlet and the port 116 can be used as an inlet. Furthermore, in the illustrated embodiment of FIG. 2C, the port 128 and the port 116 are disposed on the same circumferential end of the heat exchanger module 68, meaning both are proximal one end plate of the end plates 104a, 104b. In other embodiments, the port 128 and the port 116 can be disposed at opposite circumferential ends, meaning each is proximal to a different end plate 104a, 104b.
Since the heat exchanger fluid absorbs heat by convection, it is advantageous to provide a large magnitude of thermal coupling between the outer surface 58 of the conduit 48 and the curved inner plate 92 and between the curved inner plate 92 and the heat exchanger fluid in order to increase heat transfer from the conduit 48 to the heat exchanger fluid. One way to accomplish this is to have a serpentine flow path such as the flow path 134 shown in FIG. 2C, which ensures that the heat exchanger fluid contacts a substantial portion or virtually the entirety of the curved surface of the inner plate 92, as further shown in FIG. 2C.
In the illustrated embodiment of FIG. 2C, the serpentine flow path 134 snakes in a longitudinal direction of the conduit 48 (i.e., the axial direction in the illustrated embodiment, although other embodiments can be used with conduits that are not circular in cross section) when the heat exchanger module 68 is positioned about the conduit 48. In another embodiment, a serpentine flow path 134 may snake in a circumferential direction of the conduit 48. In such other embodiment the inlet and outlet ports of such a heat exchanger module may be disposed at diagonally opposed corners of the heat exchanger module or at the same circumferential end of the heat exchanger module.
As shown in FIG. 1, two sets of four substantially identical and separate heat exchanger modules 68a-1 through 68a-4 and 68b-1 through 68b-4 of the type described above (and shown in FIG. 2) are positioned along a length of the conduit 48. Specifically, each heat exchanger module 68a is disposed in intimate thermal contact with and surrounding or enclosing roughly the left half (as seen in FIG. 1) of the circumference of the outside surface 58 of the conduit 48. Additionally, each heat exchanger module 68b is disposed in intimate thermal contact with and surrounding or enclosing roughly the right half (as seen in FIG. 1) of the circumference of the outside surface 58 of the conduit 48. The four heat exchanger modules 68a and the four heat exchanger modules 68b are fluidically interconnected together as described in detail hereinafter and together comprise modules of the heat exchanger 60.
As further shown in FIG. 1, the modules 68a-1 through 68a-4 are connected together in series by three connection members 144a-144c while the modules 68b-1 through 68b-4 are connected together in series by three connection members 144d-144f. Specifically, each connection member 144, such as the connection member 144a couples a top port, for example, a top port 116a-1 of a first heat exchanger module 68a-1 to a bottom port 128a-2 of a second heat exchanger module 68a-2 disposed farther along (i.e., above as seen in the FIG.) a length of the conduit 48 in relation to the first heat exchanger module 68a-1. The connection member 144b interconnects a second top port 116a-2 and a third bottom port 128a-3 while the connection member 144c interconnects a third top port 116a-3 and a fourth bottom port 128a-3. The connection members 144 may connect two adjacent ports 116 and 128 to one another by a brazed or soldered joint, as shown in FIGS. 1 and 1A. Additionally, or alternatively, a port 128 of one heat exchanger module may include a female end that mates with a male end of a port 116 of another heat exchange module, as shown in FIG. 1B. In the latter case, sealing may be effectuated by an o-ring 145 and/or another seal disposed in the joint. As further shown in FIG. 1, a port 116a-4 of the uppermost heat exchanger module 68a-4 is coupled in fluid communication with a port 128b-1 of the uppermost complementary heat exchanger module 68b-1 via a connector 148 that couples the port 116a-4 and the port 128b-1. The connector 148 may be similar or identical to the connection members 144 shown in FIGS. 1A and 1B with the exception that the connector 148 is U-shaped.
The four modules 68b-1 through 68b-4 are coupled together by the connection members 144d-144f in series downstream of the modules 68a-1 through 68a-4 in the same fashion that the connection members interconnect the modules 68a.
Other interconnection schemes are possible. For example, the series-connected modules 68a may be coupled in parallel with the series-connected modules 68b by suitable use of connectors. In other embodiments, one or more modules may be coupled in a first fluidic circuit, one more modules may be coupled in a further fluidic circuit, and so on, wherein each circuit is coupled to a pump that may or may not be shared by one or more other fluidic circuits. Generally, any interconnection scheme may be used with any number of fluidic circuits, as necessary or desirable.
As further shown in FIG. 1, the heat exchanger 60 further comprises two C-shaped connectors 152, one for connecting the port 128a-1 of the lowermost heat exchanger module 68a-1 to the secondary circuit 80 (for example, for receiving heat exchanger fluid under pressure) and the other for connecting the port 116b-4 of the lowermost complementary heat exchanger module 68b-4 to the secondary circuit 80 (for example, for exhausting heat exchanger fluid). Furthermore, the heat exchanger comprises circumferential securement members 156 in the form of ring-shaped straps (or other suitable devices as noted above) to secure a heat exchanger module 68 to a complementary heat exchanger module 68a and to secure both modules 68 and 68a to the conduit 48 to form a band 64 of the heat exchanger 60. It should be understood that connection elements including the connection members 144, the U-shaped connector 148, the C-shaped connectors 152, and the securement rings 156 are only one example of connection elements that are adapted to couple the heat exchanger modules 68a, 68b in fluid communication with one another and in heat transfer relationship about the conduit 48.
The plurality of substantially identical and separate heat exchanger modules 68a, 68b that are secured in this manner by the connection elements include at least one surface defining at least one thermally conductive closed flow path extending between an inlet port and an outlet port, wherein the at least one thermally conductive flow path has a serpentine shape in a first dimension and has a shape in a second dimension adapted to conform at least substantially to a particular shape of a conduit. The at least one surface may be one of the flat surfaces 138 of one of the flow guides 132 of FIG. 2C. The flow path 134 is an example of a thermally conductive closed flow path defined by the flat surfaces 138, as shown in FIG. 2C. The flow path 134 extends between an inlet port 128 and an outlet port 116 of the heat exchanger module 68, for example. As shown in FIG. 2, the flow path 134 has a curved semi-circular shape adapted to conform at least substantially to the shape of the conduit 48 in an x dimension. Furthermore, as shown in FIG. 2C, the flow path 134 has a serpentine shape in a y dimension.
In this manner, the heat exchanger 60 shown in FIG. 1 facilitates the transfer of heat from the hot fluid 52 to the heat exchanger fluid. The heat exchanger fluid transfers the heat to the conventional heat exchanger 76 via the secondary circuit 80, as shown in FIG. 1. Furthermore, the heat exchanger 76 transfers the heat to a thermal destination 88 via the tertiary circuit 80, as further shown in FIG. 1.
It should be noted that the heat exchanger 60 shown in FIG. 1 can have any number of bands 64 of heat exchanger modules 68. To achieve increased heat transfer, the heat exchanger 60 may include an increased number of bands 64 of heat exchanger modules 68 that absorb heat from a greater surface area of the conduit 48. To achieve decreased heat transfer, the heat exchanger 60 may include a decreased number of bands 64 of heat exchanger modules 68. Furthermore, it is not necessary that the heat exchanger fluid traverse the modules 68a up the left side of the conduit 48 shown in FIG. 1 and traverse the modules 68b down the right side of the conduit 48 shown in FIG. 1. Instead, in an alternative embodiment, the heat exchanger fluid may first traverse the modules 68b and thereafter traverse the modules 68a.
Moreover, while each of the bands 64 shown in FIG. 1 comprises two heat exchanger modules 68a, 68b that together form a sheath or ring around the conduit 48, the quantity of heat exchanger modules used to form the band 64 around the conduit 48 may be 3, 4, or another suitable quantity. For example, four heat exchanger modules, each having a quarter-circle shape can be arranged to form a band 64 that substantially surrounds the conduit 48.
One advantage of the heat exchanger 60 is that since the heat exchanger 60 is in the form of a sheath disposed on the outside surface of the conduit 48 (as shown in FIG. 1), there is no need to modify the conduit to provide a volume of space within the conduit 48 specifically for heat transfer, as is the case with some conventional heat exchangers. Furthermore, the ability to remove increasing amounts of heat by adding modules to the outside of the conduit 48 means that adequate heat transfer may be accomplished without the need for high heat exchanger fluid flow rates that, in turn, can only be effectuated by high pump pressures. Thus, the risk of dangerous pressure build-up in the heat exchanger fluid flow path is reduced or eliminated. Pressure drops within the conduit 48 are also advantageously eliminated.
In one embodiment, the heat exchanger 60 shown in FIG. 1 may include heat exchanger modules 68a, 68b that are sized to conform to a conduit 48 that has a diameter of 12 inches. Alternatively, the heat exchanger modules 68a, 68b are sized to conform to a conduit 48 that has a diameter of 24 inches, or any other size conduit 48. Furthermore, the relative sizes of various parts of the heat exchange modules 68a, 68b can be modified to achieve desired levels of heat transfer. For example, the distance between the curved inner plate 92 and the curved outer plate 96 and/or the distances between adjacent flow guides 132 may be increased or decreased. It should be noted that the heat exchanger modules 68a, 68b and the connection elements of the heat exchanger 60 can be made of copper, composite material, or another appropriate material.
Referring again to FIG. 1, the pump 72 supplies heat exchanger fluid under pressure through a secondary fluid circuit 80, which includes the serpentine flow paths 134 of the modules 68a, 68b of the heat exchanger 60. The pump 72 may further comprise a control system that can be used to control the flow rate of the heat exchanger fluid through the secondary circuit 80. Controlling the flow rate, in turn, determines certain aspects of the heat transfer from the conduit 48 to the heat exchanger 60. For example, decreasing the flow rate of the heat exchanger fluid results in a higher temperature of the heat exchanger fluid because each cubic foot of heat exchanger fluid gains thermal interaction with the conduit 48 for a longer period of time before being expelled from the heat exchanger 60. A heat exchanger 60 with such a low flow rate is desirable in some situations. Following the same rationale, increasing the flow rate of the heat exchanger fluid results in a lower temperature of the heat exchanger fluid, which may be desirable in other situations. As an example, the conduit 48 of FIG. 1 may contain a gas having a temperature of eight-hundred (800) degrees Fahrenheit and the heat exchanger fluid may be water that is driven through the heat exchanger 60 at such a flow rate that the water maintains a temperature of eighty (80) degrees Fahrenheit, for example. In this way, the adjustability, modularity, and simple design of the heat exchanger 60 allows it to be used in a variety of contexts that have different heat transfer needs.
Different types of heat exchanger modules 68 can be used as parts of the heat exchanger 60. For example, the heat exchanger 60 may comprise a plurality of substantially identical and separate heat exchanger modules 68c of the type shown in FIG. 5. Generally speaking, the heat exchanger module 68c of FIG. 5 is substantially identical to the heat exchanger module 68 described above (and shown in FIG. 2C) except that the heat exchanger module 68c encloses two separate serpentine flow paths 134c-1 and 134c-2 instead of one serpentine flow path. The two serpentine flow paths 134c-1, 134c-2 are adjacent one another and each occupy about half of the space 100c enclosed by the heat exchanger module 68c, as further shown in FIG. 5. The heat exchanger module 68c includes two inlet ports 128c and two outlet ports 116c, with each flow path 134c-1 and 134c-2 having its own inlet port 128c and its own outlet port 116c. In other respects, the heat exchanger module 68c is identical to the heat exchanger module 68 of FIG. 2, as shown in FIGS. 5A, 5B, and 5C. The heat exchanger module 68c further includes a divider 157 (shown in FIGS. 8 and 8A) comprising an elongate plate that extends between upper wall 112c and lower wall 124c, as shown in FIG. 5. The divider 157 is further disposed transverse to the inner curved plate 92c such that the space 100c is divided into two. The heat exchanger module 68c includes two sets of curved flow guides 132c, one set being disposed on one side of the divider 157 and defining the first flow path 134c-1 and the other set being disposed on the other side of the divider 157 and defining the second flow path 134c-2, as shown in FIG. 5. Each set of curved flow guides 132c includes a plurality of curved flow guides 132c spaced apart from one another from the upper wall 112c to the lower wall 124c.
Referring now to FIG. 6, each flow guide 132c is a curved plate that has an arcuate length somewhat short of a quarter-circle, thereby leaving a gap 136c through which heat exchanger fluid can flow. The flow guides 132c of each set of curved flow guides 132c are arranged between the upper wall 112c and the lower wall 124c such that the gap 136c is positioned alternatively proximal the divider 157 and proximal an end plate of the end plates 104c-1, 104c-2. In other words, each successive flow guide 132c is positioned such that a gap 136c of one flow guide 132c is located at a different end than a gap 136c of a flow guide 132c immediately above or below the one flow guide 132c, as shown in FIG. 7. The first and second set of flow guides 132c are arranged with gaps 136c that alternate in this manner to define first and second flow paths 134c-1, 134c-2, respectively, as shown in FIG. 5. A first flow of heat exchanger fluid enters at the inlet port 128c shown on the left side of FIG. 5 and exits via an outlet port 116c shown on the left side of FIG. 5. A second flow of heat exchanger fluid enters at the inlet port 128c shown on the right side of FIG. 5 and exits via an outlet port 116c on the right side of FIG. 5.
In some instances, a heat exchanger 60 having two flow paths 134c-1, 134c-2 as described above may provide increased heat transfer from the conduit 48 to the heat exchanger 60 because twice as much heat exchanger fluid can be circulated through the double-path heat exchanger 60 in comparison with a single-path heat exchanger 60. In some situations, the heat exchanger 60 having two flow paths 134c-1, 134c-2 can maintain a greater temperature differential between the hot fluid 52 and the heat exchanger fluid. For example, the double-path heat exchanger 60 may maintain the heat exchanger fluid at seventy (70) degrees Fahrenheit while the hot fluid 52 has a temperature of eight-hundred (800) degrees Fahrenheit. It should be noted that the heat exchanger 60 comprised of heat exchanger modules 68c can be modified, controlled, or modularly extended in a substantially identical manner as a heat exchanger 60 of modules 68 of FIG. 2C and also may have substantially identical advantages.
In another embodiment, the heat exchanger 60 may comprise a plurality of substantially identical and separate heat exchanger modules 68d of the type shown in FIG. 9. The heat exchanger module 68d of FIG. 9 has a flow path 134d that has a shape substantially identical to the flow path 134 but the heat exchanger module 68d forms this flow path 134d using a tube-like structure 158 rather than a tank-like heat exchanger module that has plates and gaps within to define a flow path. A heat exchanger 60 comprises a plurality of heat exchanger modules 68d, each having a tube-like structure 158 that includes at least one surface defining at least one closed flow path 134d extending between an inlet port 128d and an outlet port 116d. The tube-like structure 158 is made of a thermally conductive material such that the flow path 134d is itself thermally conductive to allow heat exchanger fluid to absorb heat. The tube-like structure 158 has a serpentine or zig-zag shape in a first dimension y shown in FIG. 9 and has a shape in a second dimension x adapted to conform at least substantially to a conduit having a particular shape. In this instance, the tube-like structure 158 has a semi-circular or curved shape in the x dimension to conform to a conduit that has a cylindrical shape.
The heat exchanger 60 having a tube-like heat exchanger module 68d may further include connection elements adapted to couple the plurality of heat exchanger modules 68d to one another in fluid communication. These connection elements may be the connection members 144 and the U-shaped connector 148 shown in FIG. 1 and described in connection with FIG. 1. The connection elements may further be adapted to couple the heat exchanger modules 68d about and in heat transfer relationship with an outer surface of a conduit having a particular shape. For example, the securement ring 156 (shown in FIG. 1) may secure bands of modules 68d about and in heat transfer relationship with an outer surface 58 of the conduit 48 (again, shown in FIG. 1) that has a cylindrical shape. It should be noted that the heat exchanger 60 comprised of tube-like heat exchanger modules 68d can be modified, controlled, or modularly extended in a substantially identical manner as the heat exchanger 60 of FIG. 1 and also may have substantially identical advantages.
A flowchart for a method 160 of exchanging heat by arranging heat exchanger modules around an outside surface of a conduit for hot fluid is shown in FIG. 10. As shown in FIG. 10, the method 160 may include a step of arranging a first heat exchanger module around an outside surface of a conduit (FIG. 10—block 180). For example, a complementary heat exchanger module 68b-4 is arranged around the outside surface 58 of the conduit 48 shown in FIG. 11. As further shown in FIG. 10, the method 160 may further include a step of arranging one or more additional heat exchanger modules adjacent the first heat exchanger to form a first band that substantially surrounds the outside surface of the conduit (FIG. 10 block 200). For example, a heat exchanger module 68a-1 is arranged adjacent and opposite to the complementary heat exchanger module 68b-4 to form a first band 64, as shown in FIG. 12. As further shown in FIG. 10, the method 160 may further include a step of securing the first band to the conduit (FIG. 10—block 220). For example, a securement ring 156 may be wrapped around the pair of heat exchanger modules 68a-1, 68b-4 and tightened until the band 64 of heat exchanger modules 68a-1, 68b-4 is secured to the conduit 48, as further shown in FIG. 12. In this way, a lowermost band 64 is secured to the conduit 48.
As further shown in FIG. 10, the method 160 of exchanging heat may further include arranging one or more additional bands along a length of the conduit (FIG. 10—block 240). The one or more additional bands 64 may be arranged upstream or downstream of the first band 64 and may be arranged using a process substantially identical to the process used to arrange the lowermost band 64, which is shown in the blocks 180, 200, and 220. As shown in FIG. 13, three additional bands 64 are arranged and secured along the length of the conduit 48 in this manner.
As further shown in FIG. 10, the method 160 of exchanging heat may further include connecting a port of a first heat exchanger module with a port of a downstream or upstream heat exchanger module to create a flow path (FIG. 10—block 260). For example, as further shown in FIG. 13, connection member 144a couples an outlet port 116a-1 of a first heat exchanger module 68 to an inlet port 128a-2 of another heat exchanger module 68a-2 immediately above the first heat exchanger module 68a-1. In addition, the method 160 may include securing a U-shaped or other suitably shaped connector 148 to adjacent ports 116a-4, 128b-1 of respective adjacent heat exchanger modules 68a-4, 68b-1, as shown in FIG. 13. In this way, a flow path 134 is created that traverses the eight heat exchanger modules 68a, 68b of the heat exchanger 60.
The method 160 may further include connecting the flow path to a thermal destination (FIG. 10—block 280). This step may include coupling an inlet port 128a-1 of the lowermost heat exchanger module 68a-1 to one end of a secondary fluid circuit 80 using a C-shaped or other suitably shaped connector 152, as shown in FIG. 1. Moreover, this step may include coupling an outlet port 116b-4 of the lowermost heat exchanger module 68b-4 to another end of a secondary fluid circuit 80 using another C-shaped or other suitably shaped connector 152, as further shown in FIG. 1. The secondary fluid circuit 80 may include a pump 72 that provides heat exchanger fluid under pressure into the bottom port 128a-1 of the lowermost heat exchanger module 68a-1 such that the heat exchanger fluid is expelled at the outlet port 116b-4 of the lowermost heat exchanger module 68b-4. The secondary circuit may further include a conventional heat exchanger 76 that is in turn in fluid communication with the thermal destination 88 via a tertiary fluid circuit 84, as further shown in FIG. 1.
The method 160 may further include wrapping the bands of heat exchanger modules with insulation (FIG. 10—block 300). For example, a sheath of insulation 304 may be wrapped around the four bands 64 that make up the heat exchanger 60, as shown in FIG. 14. As further shown, insulating the heat exchanger 60 in this manner reduces heat loss from the heat exchanger 60 to the surrounding air thereby improving the efficiency of heat transfer from the conduit 48 to the thermal destination 88.
It should be noted that the method 160 can be carried out using any one or more of the alternative or modified heat exchanger modules described herein. For example, the method 160 can be carried out using the single-path heat exchanger module 68 of FIG. 2C, any modification thereof, the double-path heat exchanger module 68c of FIG. 5, any modification thereof, the tube-like heat exchanger module 68d, or any modification thereof, or any combination of these or other suitable heat exchanger modules.
The advantages of the method 160 of exchanging heat by arranging heat exchanger modules around an outside surface of a conduit for hot fluid and of the heat exchanger 60 itself are numerous. One advantage is that installation or replacement of the heat exchanger 60 is not costly or time consuming because it does not require cutting out a portion of the conduit 48 or any other modification to the conduit 48. In addition, since the conduit 48 is not substantially modified, whatever function the conduit 48 is providing can continue without interruption while the heat exchanger 60 is being installed or replaced. In addition, the modularity of the heat exchanger 60 allows for substantial changes to the magnitude of heat transfer without substantial modifications to the conduit 48.
INDUSTRIAL APPLICABILITY
In summary, a heat exchanger adapted to conform to an outside surface of a conduit for a hot fluid provides ease of adjustability regarding magnitude of heat transfer, lower manufacturing costs, and reduction of risks associated with conventional heat exchangers. In addition, a method of exchanging heat by arranging heat exchanger modules around an outside surface of a conduit for hot fluid provides easy installation and maintenance.
All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.
The use of the terms “a” and “an” and “the” and similar references in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the disclosure and does not pose a limitation on the scope of the disclosure unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure.
Numerous modifications to the present disclosure will be apparent to those skilled in the art in view of the foregoing description. It should be understood that the illustrated embodiments are exemplary only, and should not be taken as limiting the scope of the disclosure.
Patent Application
20180292139
