HEAT EXCHANGING APPARATUS AND METHOD OF SUPPORTING TUBE BUNDLE WITHIN HEAT EXCHANGER
A heat-exchange apparatus comprising a plurality of tubes bundled together, each having segmented twisted segments is disclosed. Each of the plurality of tubes provides a tube body defining an interior passageway for carrying a first fluid and a plurality of segments along its length comprising a straight section and a twisted section that are in fluid communication with each other. Each of the plurality of tubes provides a central longitudinal axis along its length. The tube body along the twisted section exhibits rotation about the central longitudinal axis and the tube body along the straight section exhibits no rotation. An exterior surface of the tube body of a tube can come into contact with an exterior surface of the tube body of another tube along the twisted section, whereas the exterior surfaces of such tubes avoid contact along the straight section.
Latest Koch Heat Transfer Company, LP Patents:
- SEG-LOK BAFFLE FOR HEAT EXCHANGER
- System and method for testing shell and tube heat exchangers for defects
- SYSTEM AND METHOD FOR TESTING SHELL AND TUBE HEAT EXCHANGERS FOR DEFECTS
- System and method for testing shell and tube heat exchangers for defects
- SYSTEM AND METHOD FOR TESTING SHELL AND TUBE HEAT EXCHANGERS FOR DEFECTS
Embodiments of the present invention relate generally to a heat exchanging apparatus, heat exchanger, method of use and method of manufacturing, and more particularly to embodiments providing a plurality of bundled round heat exchange tubes comprising individually segmented sections generally having a twisted configuration capable of operably self-supporting the respective tubes within the heat exchanger.
CROSS-REFERENCE TO RELATED APPLICATIONSThe present application claims priority to and incorporates by reference in its entirety U.S. Provisional Patent Application No. 62/660,089 titled “Tube Bundle for Heat Exchanger and Method of Supporting Same within Heat Exchanger Shell” filed on Apr. 19, 2018.
BACKGROUNDTubular heat exchangers, including shell-and-tube and hairpin (multitube) type heat exchangers, are used in a wide variety of applications to create heat exchange between streams of various fluids. Such heat exchangers generally include a combination, or bundle, of tubes housed within a cylindrically shaped shell. In operation, a first fluid, commonly referred to as the “tube-side fluid,” is directed through at least some of the tubes of the tube bundle. Concurrently, a second fluid, commonly referred to as the “shell-side fluid,” is directed within the shell and into any void around the tubes comprising the tube bundle, wherein the tube wall of each tube can permit heat exchange between the tube-side fluid stream flowing within the tubes and the shell-side fluid stream flowing around the tubes.
Generally, the tube bundle of a tubular heat exchanger includes a plurality of separate, self-contained individual tubes that extend in parallel to each other, wherein one or both of the ends of each respective tube is fixed to a header plate or a plurality of header plates, which are known as tube sheets. In applications that demand generally elongated heat exchangers of various lengths, known tubes and tube bundles, and the various designs thereof, of tubular heat exchangers, including shell-and-tube or hairpin (multitube) type heat exchangers, are subject to sagging and vibrations, both of which can negatively affect the heat exchanger and its components. To mitigate the negative effects of tube sagging and vibration, known tubes and tube bundles of tubular heat exchangers require intermediate support structures or members at various points over the length of the tubes or tube bundle. Such intermediate support structures or members can include spaced-apart baffles (e.g., segmented baffles), which generally consist of plates having holes or openings to receive and support the tubes and may further include spaces or voids for permitting the flow of shell-side fluid. In addition to supporting the tubes and maintaining the desired position of the same within the shell, such baffles may generally redirect the flow of the shell-side fluid, such that it flows across, rather than along, the tubes. In this way, such baffles generally inhibit the flow of the shell-side fluid along the length of the tubes. Other types of supports can consist of grids or rods.
Although baffles designs can vary and have any number of configurations and features to suit a particular application, baffle positioning and spacing can pose a difficult design challenge and create an impediment to efficient and optimal heat exchanger operation. In particular, when the spacing between a series of baffles is reduced to address the sagging and vibration of a specific tube or tube bundle, the limited space between the baffles can adversely affect the heat exchanger by reducing the flow area for the shell-side fluid, which results in excessive shell-side pressure drop.
Thus, there is a need in the art for an improved design for a tube, a tube bundle, and a heat exchanger that can effectively support the tube or the tube bundle within the shell for use in connection with low shell-side pressure drop designs or applications, while also avoiding sagging and vibration of the tubes.
Embodiments presented herein are generally directed to a heat-exchanging apparatus, a heat exchanger, a method of manufacture and method of carrying out heat exchange providing segmented twisted sections of bundled heat exchange tubes. Embodiments disclosed herein can be provided or practiced with any number of exemplary heat exchanger designs, including for example a shell-and-tube or hairpin (multitube) type heat exchanger or multi-pass arrangements, and/or designs implementing parallel (co-current) or counter-flow arrangements.
With reference to the drawings,
Although
As shown schematically in
As shown schematically in
The twisted sections 154, interspersed between straight sections 152, are advantageous because they can generally result in a more efficient conversion of pressure drop across the shell-side of the tubes 120 and the tube bundle 140. Specifically, the twisted sections 154, and the arrangement thereof, can mitigate the negative effects of tube sagging and vibration of the tubes 120, because the twisted sections 154, and the arrangement thereof, increases the mechanical resonant frequency of the tube 120, which can make the tubes 120 and any bundle 140 of such tubes 120 more resistant to lateral deflection from forces generated by shell-side fluid flow through the heat exchanger 100. In this way, the twisted sections 154, and the arrangement thereof with straight sections 152, eliminate the need for closely-spaced intermediate support structures or members at various points along the length thereof and, in some instances, the need for intermediate support structures or members at all. The improvement being advantageous over tubes, arrangements of tubes, and tube bundles that comprise either entirely straight tubes or tubes that are twisted over their entire lengths, without the alternating series of individually segmented straight sections and twisted sections 150. Further, the twisted sections 154 can promote the efficiency of heat transfer between tube-side fluid and shell-side fluid when compared to known tube arrangements. First, by eliminating the need for closely-spaced intermediate support structures or members at various points on the length of the tube 120 or tube bundle 140, such configuration requires less baffles, or even no baffles, to support and maintain the tubes 120 or the tube bundle 140, which reduces the inhibiting effect of such baffles on the flow of the shell-side fluid along the length of the tubes. Second, by eliminating the need for closely-spaced intermediate support structures or members at various points on the length of the tube 120 or tube bundle 140, such configuration does not create the excessive shell-side pressure drop common to known configurations and spacings of baffles used in heat exchangers.
As shown schematically in
Each of
According to embodiments presented herein, and shown representatively in
Further, because a twisted section 154 is generally adjacent to an at least one straight section 152, wherein the tubes 120 of the tube bundle 140 are generally arranged in a tighter arrangement with fewer and smaller voids between the tubes, the overall mechanical resonance of the tube 120 is not adversely affected by the spacing and voids 180 of the twisted section 154. The intermittent twisted segments 154 can support the tubes 120 and tube bundles 140 within the shell in a manner that provides a highly flexible support system with enhanced heat transfer on the tube- and shell-side flows, such that each tube 120 or tube bundle 140 is generally self-supporting, even without the use of baffles. Such support can be achieved, at least in part, by the twisted segments 154 which can produce tube-to-tube spaced-apart contact points 170 between adjacent tubes 120, while also defining the voids 180 discussed herein, with each individual tube 120 being secured in place by adjacent tubes 120, and facilitating securement of adjacent tubes 120. Such arrangement can reduce vibration and promote easier cleaning on the shell-side through the heat exchanger 100.
It is important to note that the present inventions (e.g., inventive concepts, and so on) have been described in the specification and/or illustrated in the FIGURES of the present patent document according to exemplary embodiments; the embodiments of the present inventions are presented by way of example only and are not intended as a limitation on the scope of the present inventions. The construction and/or arrangement of the elements of the inventive concepts embodied in the present inventions as described in the specification and/or illustrated in the FIGURES is illustrative only. Although exemplary embodiments of the present inventions have been described in detail in the present patent document, a person of ordinary skill in the art will readily appreciate that equivalents, modifications, variations, and so on of the subject matter of the exemplary embodiments and alternative embodiments are possible and contemplated as being within the scope of the present inventions; all such subject matter (e.g., modifications, variations, embodiments, combinations, equivalents, and so on) is intended to be included within the scope of the present inventions. It should also be noted that various/other modifications, variations, substitutions, equivalents, changes, omissions, and so on may be made in the configuration and/or arrangement of the exemplary embodiments (e.g., in concept, design, structure, apparatus, form, assembly, construction, means, function, system, process/method, steps, sequence of process/method steps, operation, operating conditions, performance, materials, composition, combination, and so on) without departing from the scope of the present inventions; all such subject matter (e.g., modifications, variations, embodiments, combinations, equivalents, and so on) is intended to be included within the scope of the present inventions. The scope of the present inventions is not intended to be limited to the subject matter (e.g., details, structure, functions, materials, acts, steps, sequence, system, result, and so on) described in the specification and/or illustrated in the FIGURES of the present patent document. It is contemplated that the claims of the present patent document will be construed properly to cover the complete scope of the subject matter of the present inventions (e.g., including any and all such modifications, variations, embodiments, combinations, equivalents, and so on); it is to be understood that the terminology used in the present patent document is for the purpose of providing a description of the subject matter of the exemplary embodiments rather than as a limitation on the scope of the present inventions.
It is also important to note that according to exemplary embodiments the present inventions may comprise conventional technology (e.g., as implemented and/or integrated in exemplary embodiments, modifications, variations, combinations, equivalents, and so on) or may comprise any other applicable technology (present and/or future) with suitability and/or capability to perform the functions and processes/operations described in the specification and/or illustrated in the FIGURES. All such technology (e.g., as implemented in embodiments, modifications, variations, combinations, equivalents, and so on) is considered to be within the scope of the present inventions of the present patent document.
Claims
1. A heat-exchanging apparatus comprising:
- a plurality of tubes bundled adjacent one another, each of the plurality of tubes having a tube body defining an interior passageway for carrying a first fluid, each of the plurality of tubes having a plurality of segments along its length comprising a straight section and a twisted section in fluid communication with each other;
- wherein each of the plurality of tubes has a central longitudinal axis along its length, the tube body along the twisted section exhibiting rotation about the central longitudinal axis, the tube body along the straight section exhibiting no rotation about the central longitudinal axis, and
- an exterior surface of the tube body of a first tube of the plurality of tubes coming into contact with an exterior surface of the tube body of a second tube of the plurality of tubes along the twisted section, the exterior surfaces of the first and second tubes avoiding contact along the straight section.
2. The heat-exchanging apparatus of claim 1 further comprising an area around and between the plurality of tubes, the area forming a passageway for carrying a second fluid.
3. The heat-exchanging apparatus of claim 1 wherein the plurality of segments of each tube comprises an alternating arrangement of straight and twisted sections, wherein the twisted section is located between first and second straight sections and the straight section is located between first and second twisted sections.
4. The heat-exchanging apparatus of claim 3 wherein the alternating arrangement of straight and twisted sections of each of the plurality of tubes are in line with one another, the twisted section of the first tube being adjacent the twisted section of the second tube, the straight section of the first tube being adjacent to the straight section of the second tube.
5. The heat exchanging apparatus of claim 1 wherein rotation of the tube body of each of the plurality of tubes in the twisted section is synchronized such that rotation of the first tube corresponds with rotation of the second tube.
6. The heat-exchanging apparatus of claim 2 wherein rotation of the tube body along the at least one twisted section causes the second fluid to exhibit a swirling action as it flows along the twisted section.
7. The heat exchanging apparatus of claim 1 wherein the tube body of each of the plurality of tubes is rotated at least 360° about its central longitudinal axis along each of the twisted sections, contact points between the twisted section of the first tube and adjacent twisted sections of other adjacent tubes of the plurality of tubes being made at rotation intervals on the order of 60° through said 360° rotation.
8. The heat exchanging apparatus of claim 1 wherein upon entering the twisted section the each of the plurality of tubes are in a first rotation orientation whereby the exterior surface of the tube body of the first tube contacts the exterior surface of the tube body of the second tube, the exterior surfaces of the tube bodies of the first and second tubes separating from one another as the tubes rotate through the twisted section away from the first rotation orientation and coming back into contact with one another when the tubes are rotated at rotation intervals on the order of 180° from the first rotation orientation.
9. The heat exchanging apparatus of claim 8 wherein the exterior surface of the tube body of the first tube comes into contact with an exterior surface of a tube body of a third tube of the plurality of tubes when the tubes are rotated at rotation intervals on the order of 60° and 240° from the first rotation orientation.
10. The heat exchanging apparatus of claim 1 wherein the tube body of each of the plurality of tubes has a substantially round cross-section profile occupying a given area along the straight section, the round cross-section profile being compressed through the twisted section, said compression causing a reduction of the given area and flattening of the round cross-section profile whereby opposing points of said round cross-sectional profile protrude outward.
11. The heat exchanging apparatus of claim 10 wherein outward protrusion of opposing points of the tube body of the first tube in the twisted section permits contact with opposing points of the tube body of the second tube.
12. A heat exchanger comprising:
- a plurality of tubes bundled adjacent one another, each of the plurality of tubes having a tube body defining an interior passageway for carrying a first fluid, each of the plurality of tubes having a plurality of segments along its length comprising a plurality of alternating straight sections and a plurality of twisted sections in fluid communication with each other, the straight sections of the plurality of tubes being in alignment with one another and the twisted sections of the plurality of tubes being in alignment with one another;
- a shell surrounding the plurality of tubes, the shell defining an area around and between the plurality of tubes, the area forming a passageway for carrying a second fluid;
- wherein each of the plurality of tubes has a central longitudinal axis along its length, the tube body along the twisted sections exhibiting rotation about the central longitudinal axis, the tube body along the straight sections exhibiting no rotation about the central longitudinal axis;
- an exterior surface of the tube body of a first tube of the plurality of tubes coming into contact with an exterior surface of the tube body of a second tube of the plurality of tubes along the twisted sections, the exterior surfaces of the first and second tubes avoiding contact along the straight sections.
13. The heat exchanger of claim 12 wherein rotation of the tube body of each of the plurality of tubes in the twisted sections is synchronized where rotation of the first tube corresponds to rotation of the second tube.
14. The heat exchanger of claim 12 wherein rotation of the tube body along the twisted sections causes the second fluid to exhibit a swirling action as it flows along the twisted sections.
15. The heat exchanger of claim 12 wherein the tube body of each of the plurality of tubes is rotated at least 360° along the twisted sections, contact between adjacent tubes being made at rotation intervals on the order of 60° through said rotation of said tube bodies.
16. The heat exchanger of claim 12 wherein the tube body of each of the plurality of tubes has a substantially round cross-section profile occupying a given area along the straight sections, the round cross-section profile being compressed through the twisted sections, said compression causing a reduction of the given area and flattening of the round cross-section profile whereby opposing points on said profile protrude outward.
17. The heat exchanger of claim 16 wherein outward protrusion of opposing points of the tube body of the first tube in the twisted sections permits contact with opposing points of the tube body of the second tube.
18. A method of carrying out heat exchange comprising:
- introducing a first fluid into a plurality of tubes of a heat exchanging apparatus, the plurality of tube being bundled together, the each of the plurality of tubes having a central longitudinal axis along its respective length and comprising a plurality of straight sections and a plurality of twisted sections, the plurality of straight sections and plurality of twisted sections being in an alternating arrangement along a length of the tubes, the plurality of twisted sections exhibiting rotation about the about the central longitudinal axis, the plurality of straight sections exhibiting no rotation about the central longitudinal axis;
- directing a second fluid into the heat exchanging apparatus into an area adjacent the plurality of bundled tubes;
- permitting the first fluid to flow within the plurality of tubes through the alternating arrangement of straight sections and twisted sections;
- supporting the plurality of tubes within the heat exchanging apparatus at contact points along the plurality of twisted sections, the contact points being locations along the plurality of twisted sections where adjacent tubes of the plurality of tubes contact one another.
19. The method of claim 16 further comprising causing the second fluid to exhibit a swirling action as it flows along the plurality of twisted sections.
20. (canceled)
21. The method of claim 19 wherein forming the plurality of segments along the length of each of the plurality of tubes further comprising rotating each tube body of each twisted section at least 360° about its central longitudinal axis, said rotation of each twisted section along a first tube of the plurality of tubes providing contact points with adjacent twisted sections of other adjacent tubes of the plurality of tubes at rotation intervals on the order of 60°.
Type: Application
Filed: Apr 18, 2019
Publication Date: May 13, 2021
Applicant: Koch Heat Transfer Company, LP (Houston, TX)
Inventors: Byron BLACK (Houston, TX), Prashant JADHAV (Houston, TX), Marco FAZZINI (Houston, TX), Donald WOODS (Houston, TX), Nathan BARNETT (Houston, TX)
Application Number: 17/046,304