BACKGROUND OF THE INVENTION
1. Field of the Invention
Embodiments of the invention generally relate to systems and methods for draining fluids from a heat exchange system to protect against damage resulting from freezing of a fluid within the heat exchange system. Particularly, embodiments of the invention relate to removing liquid from one or more tubes of the heat exchange system using one or more drainage conduits. More particularly, embodiments of the invention relate to a drainage manifold that is in communication with one or more tubes of a (finned or bare tube) tube heat exchange system and is operable to drain a liquid, such as water, from the tubes when the heat exchange system is not in use.
2. Description of the Related Art
Heat exchangers are used to efficiently exchange heat from one fluid to another fluid. The fluids are generally separated by a partition so that the fluids are not in direct contact with each other. A typical heat exchanger may include a series of tubes through which a first fluid is directed, the first fluid being either heated or cooled by a second fluid that is directed over the outer surface of the tubes. The tubes may also include one or more fins connected to their outer surface to increase the contact area between the fluids, which may increase the heat transfer efficiency.
A potential problem with tube heat exchangers is structural damage to the tubes caused by freezing of the fluid within the tubes, particularly when water is employed as the fluid. This can occur in cold weather during storage or transport of the heat exchanger, and can also occur after installation if the heat exchanger is subjected to freezing conditions due to power or mechanical failure. Specifically, when the heat exchange system is not in use, water that remains idle in the tubing will freeze at the appropriate temperature conditions. Such freezing can lead to the rupture of a wall or joint of the heat exchanger tube(s) and therefore lead to failure of the heat exchange system.
One known method of avoiding damage to the heat exchange tubing is to prevent freezing of the fluid by adding anti-freeze agents to the fluid. For example, when water is used as the fluid, ethylene glycol may be added to lower the freezing point of the water. However, large amounts of anti-freeze agents are required to prevent freezing, which produces a mixture whose characteristics differ substantially from those of water. This can result in altered performance and reduced heat transfer by the heat exchange system. Moreover, anti-freeze agents can be expensive when required in large quantities and may be toxic to the surrounding environment in the event of leakage or spillage.
Therefore, there is a need for a system and method for protecting heat exchangers from damage due to freezing.
SUMMARY OF THE INVENTION
In one embodiment, a heat exchange system may include an inlet manifold, an outlet manifold, and a plurality of tubes in communication with the inlet and outlet manifolds. The plurality of tubes may include a first tube located adjacent to a second tube. A first conduit may be in communication with the first tube at a location between the inlet and outlet manifolds. A second conduit may be in communication with the second tube at a location between the inlet and outlet manifolds. The first and second conduits may be configured to drain fluid from the plurality of tubes.
In one embodiment, a heat exchange system may include a housing, an inlet manifold, an outlet manifold, and a first tube in communication with the inlet and outlet manifolds. The first tube may repeatedly extend from a first end to a second end of the housing, thereby forming at least a first bend portion. A first conduit may be in communication with the first bend portion at a location between the inlet and outlet manifolds, such that the first conduit is operable to drain fluid from the first tube.
In one embodiment, a heat exchange system may include a plurality of rows of tubes in communication with an inlet manifold and an outlet manifold. And a drain conduit may be in communication with a tube of each row at a location between the inlet and outlet manifolds to drain fluid from the heat exchange system.
In one embodiment, a heat exchange system may include a drainage conduit in communication with one or more tubes of the heat exchange system at a location between an inlet and an outlet of the one or more tubes. And a plug may be coupled to the drainage conduit to allow drainage of fluid from one or more tubes.
In one embodiment, a method of draining fluid from a heat exchange system may include providing one or more of the heat exchange systems described herein, and draining fluid from the heat exchange system using the drainage manifold when not in use.
In one embodiment, a method of draining fluid from a heat exchange system may include supplying fluid to an inlet manifold; flowing fluid from the inlet manifold through a plurality of tubes; returning fluid to an outlet manifold from the plurality of tubes; and removing a portion of the fluid from the plurality of tubes via a drainage manifold that is in fluid communication with the plurality of tubes at a location between the inlet and outlet manifolds.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above recited features of the invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
FIG. 1A illustrates a top view of a heat exchange system according to one embodiment.
FIG. 1B illustrates a front view of the heat exchange system according to one embodiment.
FIG. 1C illustrates a left side view of the heat exchange system according to one embodiment.
FIG. 1D illustrates a right side view of the heat exchange system according to one embodiment.
FIG. 2 illustrates a top view of a drainage manifold of the heat exchange system according to one embodiment.
FIGS. 3A and 3B illustrate front and side views of the drainage manifold according to one embodiment. The inlet and outlet manifolds omitted for clarity.
FIG. 4 illustrates a top view of the drainage manifold of the heat exchange system according to one embodiment.
FIGS. 5A and 5B illustrate front and side views of the drainage manifold according to one embodiment. The inlet and outlet manifolds omitted for clarity.
FIG. 6 illustrates a top view of the drainage manifold of the heat exchange system according to one embodiment.
FIGS. 7A and 7B illustrate front and side views of the drainage manifold according to one embodiment. The inlet and outlet manifolds omitted for clarity.
FIG. 8A illustrates a top view of the heat exchange system according to one embodiment.
FIG. 8B illustrates a front view of the heat exchange system according to one embodiment.
FIG. 8C illustrates a left side view of the heat exchange system according to one embodiment.
FIG. 8D illustrates a right side view of the heat exchange system according to one embodiment.
FIG. 9 illustrates a top view of FIGS. 8A and 8B which are of the drainage manifold of the heat exchange system according to one embodiment.
DETAILED DESCRIPTION
FIGS. 1A-1D illustrate top, front, left, and right side views of a heat exchange system 10 according to one embodiment. The heat exchange system 10 includes a housing 15, an inlet manifold 20, an outlet manifold 30, a plurality of tubes 40, a plurality of fins 50, and three embodiments of a drainage manifold 60A, 60B, and 60C. The housing 15 may include a rectangular-shaped structure that supports the plurality of tubes 40 and fins 50; the fins 50 being coupled to the tubes 40 to increase the outer surface area of the tubes 40. The fins 50 may also serve to increase the structural integrity of the heat exchange system 10. In one embodiment, the fins 50 may include a variety of shapes and sizes, including straight, wavy, or combinations thereof. The fins 50 may extend radially from the outer surface of the tubes 40 and/or may be in the form of a sleeve surrounding the outer surface of the tubes 40. The plurality of tubes 40 and fins 50 are located in the housing 15 so that a fluid, such as air, may flow through the housing 15 (e.g., from the front of the housing 15 to the back of the housing 15) and directly contact the outer surface area of the tubes 40 and fins 50. The housing 15, tubes 40, and fins 50 may be arranged to provide uniform fluid flow through the housing 15 and maximize fluid contact with the outer surfaces of the tubes 40 and fins 50.
The plurality of tubes 40 may be in communication with the inlet manifold 20 at a first end to receive fluid and may be in communication with the outlet manifold 30 at a second end to expel the fluid. The inlet and outlet manifolds 20, 30 may include any type of fluid-handling members, such as cylindrical housings, headers, conduits, etc. that are configured to disperse, direct, and/or receive fluid into or from the plurality of tubes 40. Each manifold 20, 30 may include an inlet and outlet fluid line connection 25, 35 for supply and return of fluid from one or more supply/return tanks. In one embodiment, the inlet fluid line connection 25 may be coupled to a lower end of the inlet manifold 20, and the outlet fluid line connection 35 may be coupled to an upper end of the outlet manifold 30. Each manifold 20, 30 may also be located adjacent to the housing 15 and/or on similar or different sides of the housing 15.
In one embodiment, the plurality of tubes 40 may include a first tube 42 and a second tube 44 (illustrated in FIG. 2) that each traverse a length 43 of the housing 15 one or more times, beginning at the inlet manifold 20 and terminating at the outlet manifold 30. The first tube 42 may be spaced apart from the second tube 44 in both horizontal and vertical directions (illustrated in FIG. 3). The first and second tubes 42, 44 may each start at a connection with the inlet manifold 20, extend across the length 43 of the housing 15 away from the inlet manifold 20, and then form a 180 degree bend 19 so that the tubes may extend back across the length 43 of the housing 15 toward the inlet and outlet manifolds 20, 30. The first and second tubes 42, 44 may then form another 180 bend upon reaching an end of the housing 15 adjacent to the inlet and outlet manifolds 20, 30 and extend back across the length 43 of the housing 15 as previously described. This tubing pattern may be repeated numerous times, limited only by spatial limitations of the housing 15 and sizing of the plurality of tubes 40, until each tube terminates at a connection with the outlet manifold 30.
The longitudinal lengths of the plurality of tubes 40, including the bend portions, may lie substantially in the same plane to thereby form a row 49 of tubing (also illustrated in FIGS. 3A and 3B). In one embodiment, the plane in which each tube lies is at a downward angle relative to the horizontal axis of the housing 15 in the direction of the outlet manifold 30. In this manner, the first and second tubes 42, 44 are tilted towards the outlet manifold 30 to assist fluid flow into the outlet manifold 30 with the assistance of gravity, as illustrated along edge 17 of the front view of housing 15 in FIG. 1B. In one embodiment, the plane in which each tube lies is substantially parallel to the horizontal axis of the housing 15. In one embodiment, the plurality of tubes 40 may include multiple rows 49 of tubing that extend along the height 41 of the housing 15, and from the top to the bottom of each manifold 20, 30. The rows 49 of tubing may be symmetrically and/or uniformly spaced above and below each other, thereby forming a tubing stack.
FIG. 2 illustrates a top view of the drainage manifold 60A according to one embodiment. The drainage manifold 60A is configured to remove liquid from the plurality of tubes 40 when the heat exchange system 10 is not in use or operation, such as during transportation, storage, and/or a downtime failure of the heat exchange system 10. The drainage manifold 60A includes a plurality of first drain conduits 62, a second drain conduit 64, a third drain conduit 66, and a stop member 68, such as a plug.
In one embodiment, each of the first and second tubes 42, 44 traverse the length 43 of the housing 15, thereby forming bends 46A, 46B and 48A, 48B, respectively, that are located adjacent to the inlet and outlet manifolds 20, 30. In one embodiment, the bends 46A, 46B, 48A, 48B may be U-shaped, V-shaped, square-shaped, triangular-shaped, or combinations thereof.
In one embodiment, there are a total of four first drain conduits 62A, 62B, 62C, 62D that provide communication between the first and second tubes 42, 44 and the second drain conduit 64. Two of the first drain conduits 62A, 62C are in communication with the first tube 42. In particular, each of the first drain conduits 62A, 62C are coupled to one of the bends 46A, 46B of the first tube 42. The other two first drain conduits 62B, 62D are in communication with the second tube 44. In particular, each of the first drain conduits 62B, 62D are coupled to one of the bends 48A, 48B of the second tube 44. The second drain conduit 64 operates like a manifold that channels fluid from all four of the first drain conduits 62A, 62B, 62C, 62D into the third drain conduit 66. The third drain conduit 66 may be sealed at its outlet by the stop member 68 during operation of the heat exchange system 10. The stop member 68 may be removed when desired to remove liquid from the plurality of tubes 40 via the drainage manifold 60A.
As further illustrated in FIG. 2, the bends 46A, 46B of the first tube 42 are configured so that they extend farther away from the housing 15 than the bends 48A, 48B of the second tube 44, and so that they are positioned directly above the second drain conduit 64 of the drainage manifold 60A. The bends 46A, 46B of the first tube 42 are also angled so that they are spaced farther away from the bends 48A, 48B of the second tube 44 to provide a more accessible working space when coupling the drainage manifold 60A to the heat exchange system 10. In one embodiment, the “legs” of the bends 46A, 46B may be positioned at about 45 degree angles relative to the longitudinal length of the first tube 42, thereby forming a generally “V-shaped” bend. The first drain conduits 62A, 62C of the drainage manifold 60A may be coupled to the “tips” of the bends 46A, 46B so that they are positioned directly above the second drain conduit 64. In this manner, the lower ends of the first drain conduits 62A, 62C can be directly connected to a top of the second drain conduit 64. The first drain conduits 62B, 62D may be positioned adjacent to the second drain conduit 64 and may include connection members 69, such as an “L-shaped” or 90 degree bend connector, to facilitate connection to a side of the second drain conduit 64 (also illustrated in FIG. 3B).
FIGS. 3A and 3B illustrate the drainage manifold 60A with the inlet and outlet manifolds 20, 30 removed for clarity. As illustrated, two of the first drain conduits 62A, 62C are directly connected to the upper end of the second drain conduit 64; and the other two of the first drain conduits 62B, 62D are connected to the side of the second drain conduit 64 via connection members 69. Also illustrated is the first tube 42 in communication with first drain conduits 62B, 62D and the second tube 44 in communication with first drain conduits 62A, 62C. The first and second tubes 42, 44 may form the row (or circuit) 49 of tubing described above, and multiple rows 49 are located adjacent to each other, e.g. above and below each other, to form a tubing stack. In this manner, the first drain conduits 62A, 62B, 62C, 62D are in communication with each row 49 of tubing that forms the tubing stack. The first drain conduits 62A, 62C are in communication with the respective bends of each first tube 42 of each row 49 and extend farther away from the housing 15 such that they are positioned directed above the second drain conduit 64. The first drain conduits 62B, 62D are in communication with the respective bends of each second tube 44 of each row 49 and are positioned in the space between the housing 15 and the second drain conduit 64. The first drain conduits 62A, 62B, 62C, 62D extend across the height 41 of the housing 15, from the top to the bottom of the inlet and outlet manifolds 20, 30. The first drain conduits 62A, 62B, 62C, 62D thus also provide communication between each row (or circuit) 49 of tubing that forms the tubing stack.
In one embodiment, the longitudinal lengths of the first drain conduits 62A, 62B, 62C, 62D may be substantially perpendicular to the longitudinal lengths of the second and/or third drain conduits 64, 66. The longitudinal length of the second drain conduit 64 may be substantially perpendicular to the longitudinal length of the third drain conduit 66. In one embodiment, the first drain conduits 62A, 62B, 62C, 62D are sealed at their upper ends to direct fluid into the second drain conduit 64 at their lower ends.
FIG. 4 illustrates a top view of the drainage manifold 60B according to one embodiment. The drainage manifold 60B includes many of the same components of the drainage manifold 60A, which are identified by the same reference numerals. The primary differences between the drainage manifold 60A and 60B are the configuration of the bends 46A, 46B of the first tube 42; and the configuration of the first drain conduits 62A, 62C. As illustrated, the bends 46A, 46B of the first tube 42 are generally “U-shaped,” similarly and symmetrically relative to the bends 48A, 48B of the second tube 44. As further illustrated, the first drain conduits 62A, 62C are connected to the bends 46A, 46B of the first tube 42 equidistant from the housing 15 and the second drain conduit 64 as the first drain conduits 62B, 62D. Each of the first drain conduits 62A, 62B, 62C, 62D may thus be connected to the second drain conduit 64 via bend connectors 69.
FIGS. 5A and 5B illustrate the drainage manifold 60B with the inlet and outlet manifolds 20, 30 removed for clarity. As illustrated, the first drain conduits 62A, 62B, 62C, 62D are in communication with each row (or circuit) 49 of tubing that forms the tubing stack. The first drain conduits 62A, 62C are in communication with the respective bends of each first tube 42 of each row (or circuit) 49 and are positioned in the space between the housing 15 and the second drain conduit 64. The first drain conduits 62B, 62D are in communication with the respective bends of each second tube 44 of each row (or circuit) 49 and are similarly positioned in the space between the housing 15 and the second drain conduit 64, adjacent to the first drain conduits 62A, 62C. The first drain conduits 62A, 62B, 62C, 62D extend across the height 41 of the housing 15, from the top to the bottom of the inlet and outlet manifolds 20, 30. The first drain conduits 62A, 62B, 62C, 62D thus provide communication between each row 49 of tubing that forms the tubing stack. The longitudinal lengths of the first drain conduits 62A, 62B, 62C, 62D may be substantially perpendicular to the longitudinal lengths of the second and/or third drain conduits 64, 66. The longitudinal length of the second drain conduit 64 may be substantially perpendicular to the longitudinal length of the third drain conduit 66. In one embodiment, the first drain conduits 62A, 62B, 62C, 62D are sealed at their upper ends and may direct fluid into the second drain conduit 64 at their lower ends. Finally illustrated are the first drain conduits 62A, 62B, 62C, 62D connected to the side of the second drain conduit 64 via connection members 69.
FIG. 6 illustrates a top view of the drainage manifold 60C according to one embodiment. As illustrated, the bends 46A, 46B, 48A, 48B of the first and second tube 42, 44 are generally “U-shaped” and are symmetrically arranged relative to the housing 15. As further illustrated, the drainage manifold 60C includes only two first drain conduits 62A, 62B that are in communication with the plurality of tubes 40. One of the first drain conduits 62A is coupled to bends 46A, 48A of first and second tubes 42, 44. And the other one of the first drain conduits 62B is coupled to bends 46B, 48B of first and second tubes 42, 44. Each of the bends 46A, 46B, 48A, 48B are in communication with the respective first drain conduit 62A, 62B via a connection member 69. In one embodiment, the connection member 69 may include a tubular member perpendicularly extending between each bend 46A, 46B, 48A, 48B and the respective first drain conduit 62A, 62B. The first drain conduits 62A, 62B may each include an upper portion of the conduit that is substantially parallel to the height of the housing 15 and a lower portion of the conduit that is substantially perpendicular to the height of the housing 15, thereby forming a generally “L-shaped” configuration. The first drain conduits 62A, 62B may also each include a middle portion of the conduit that is angled inward relative to the height of the housing 15 to locate the lower portion of the conduit inward or between the outlet manifolds 20, 30. The first drain conduits 62A, 62B may also include stop members 68A, 68B, respectively, to open and close fluid communication with the drainage manifold 60C. The first drain conduits 62A, 62B may thus be sealed during operation of the heat exchange system 10, and may be configured to drain fluid from the heat exchange system 10 when not in use or operation.
FIGS. 7A and 7B illustrate the drainage manifold 60D with the inlet and outlet manifolds 20, 30 removed for clarity. As illustrated, the first drain conduits 62A, 62B, are in communication with the bends 46A, 48A and 46B, 48B respectively of each row 49 of tubing that forms the tubing stack. The first drain conduits 62A, 62B, extend across the height 41 of the housing 15, from the top to the bottom of the inlet and outlet manifolds 20, 30. The first drain conduits 62A, 62B thus provide communication between each row 49 of tubing that forms the tubing stack. In one embodiment, the first drain conduits 62A, 62B are sealed at their upper ends to direct fluid from the upper portion of the conduits to the lower portions of the conduits. Finally illustrated are the connection members 69 symmetrically positioned (above and below each other, as well as adjacent to each other) with respect to the bends 46A, 46B, 48A, 48B and the first drain conduits 62A, 62B.
FIGS. 8A-8D illustrate a top, front, left, and right side views of a heat exchange system 100 according to one embodiment. The heat exchange system 100 includes many of the same components of the heat exchange system 10, which are identified by the same reference numerals. The plurality of tubes 40 includes the first tube 42, the second tube 44, and a third tube 45 that are each in communication with the inlet and outlet manifolds 20, 30. The first, second, and third tubes 42, 44, 45 each traverse the length 43 of the housing 15 one or more times, beginning at the inlet manifold 20 and terminating at the outlet manifold 30. The first tube 42 may be spaced apart from the second and third tubes 44, 45 in the horizontal and/or vertical directions, and may form a 180 degree bend 19 that has a larger bend radius than the bends of the other tubes. The longitudinal lengths of the plurality of tubes 40, including the bend portions, may lie substantially in the same plane to thereby form rows 49 of tubing. In one embodiment, the plane in which the plurality of tubes 40 lies is at a downward angle relative to the horizontal axis of the housing 15 in the direction of the outlet manifold 30. In this manner, the first, second, and third tubes 42, 44, 45 are tilted towards the outlet manifold 30 to assist fluid flow into the outlet manifold 30 with the assistance of gravity, as similarly illustrated along edge 17 of the front view of housing 15 in FIG. 1B. In one embodiment, the plane in which each tube lies is substantially parallel to the horizontal axis of the housing 15, as illustrated along edge 17 of the front view of the housing 15 in FIG. 8B. In one embodiment, the plurality of tubes 40 may include multiple rows 49 of tubing that extend along the height 41 of the housing 15, and from the top to the bottom of each manifold 20, 30. The rows 49 of tubing may be symmetrically and/or uniformly spaced above and below each other, thereby forming a tubing stack.
FIG. 9 illustrates a top view of a drainage manifold 60D according to one embodiment. The drainage manifold 60D includes a single drain conduit 62 that is in communication with the plurality of tubes 40 between the inlet and outlet manifolds 20, 30. The drain conduit 62 may be positioned between the inlet and outlet manifolds 20, 30 and located equidistant from the housing 15 as well. The drain conduit 62 may be coupled to bends of first, second, and third tubes 42, 44, 45. In one embodiment, a first half of the first, second, and third tubes 42, 44, 45 may extend from the inlet manifold 20 and terminate in the drain conduit 62. A second half of the first, second, and third tubes 42, 44, 45 may extend from the drain conduit 62 and terminate in the outlet manifold 30. The drain conduit 62 is in communication with the first, second, and third tubes 42, 44, 45 of each row 49 of tubing to collect fluid from the plurality of tubes 40 and direct the fluid to a location separate and/or away from the heat exchange system 100. The drain conduit 62 extends across the height 41 of the housing 15, from the top to the bottom of the inlet and outlet manifolds 20, 30. The drain conduit 62 thus provides communication between each row 49 of tubing that forms the tubing stack. In one embodiment, the drain conduit 62 is sealed at its upper end to direct fluid from the upper portion of the conduit to the lower portion of the conduit. The drain conduit 62 may also include stop member 68 located at a bottom end of the conduit to open and close fluid communication with the drainage manifold 60D. The drain conduit 62 may thus be sealed during operation of the heat exchange system 100, and may be configured to drain fluid from the heat exchange system 100 when not in use or operation.
In one embodiment, a plurality of heat exchange systems 10 and/or 100 described herein may be in communication with each other. In one embodiment, a plurality of tubes 40 of a first heat exchange system may be in communication with a plurality of tubes 40 of a second heat exchange system. In one embodiment, an inlet manifold 20 and/or an outlet manifold 30 of a first heat exchange system may be in communication with an inlet manifold 20 and/or outlet manifold 30 of a second heat exchange system. In one embodiment, a drainage manifold 60 of a first heat exchange system may be in communication with a drainage manifold 60 a second heat exchange system to drain fluid from the group of heat exchange systems. In one embodiment, the first, second, and/or third drain conduits 62, 64, 66 of a drainage manifold of a first heat exchange system may be in communication with a first, second, and/or third drain conduit 62, 64, 66 of a drainage manifold of a second heat exchange system. Multiple combinations of heat exchange systems 10, 100 and drainage manifolds 60A-D may be provided using embodiments of the systems and manifolds described herein.
In one embodiment, the various tubing connections between the plurality of tubes 40, the inlet and outlet manifolds 20, 30, and/or the drainage manifolds 60A-D may be formed by brazing, welding, or other methods known by one of ordinary skill in the art. In one embodiment, the housing 15, the plurality of tubes 40, the inlet and outlet manifolds 20, 30, and/or the drainage manifolds 60A-D may be equipped with one or more vent and/or drain ports to facilitate removal of liquid from the heat exchange system 10.
While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
Patent Application
20140076518
