Heat exchanger tube core and heat exchanger

Abstract

The present application discloses a heat exchanger tube core. At least one heat exchange tube of the heat exchanger tube core includes a hollow tube body of the heat exchange tube extending in the longitudinal direction, and a heat exchange tube inlet and a heat exchange tube outlet at both ends of the hollow tube body of the heat exchange tube. The hollow tube body of the heat exchange tube has a non-circular cross-section taken perpendicular to the tube axis at least in a portion between both ends of the hollow tube body of the heat exchange tube, and the width of the non-circular cross-section is greater than the height; the portion with the non-circular cross-section between both ends of the hollow tube body of the heat exchange tube is wound into a spiral around a central axis, and the width direction of the cross-section of the heat exchange tube portion wound into a spiral is parallel to the central axis direction. A heat exchanger including the heat exchanger tube core is also disclosed. The heat exchanger tube core and the heat exchanger of the present application adopt heat exchange tubes with non-circular cross-sections and make the width direction of the cross-section of the non-circular cross-section heat exchange tubes parallel to the central axis direction of the heat exchanger, which can reduce the flow resistance of the fluid medium and the post-tube retention area, increase the heat exchange area, and thus improve the heat exchange efficiency.

Description

Technical Field

[0001] The present invention relates to the field of waste heat recovery in industries such as oil refining and chemical engineering. Specifically, it relates to a heat exchanger tube core and a heat exchanger for improving heat exchange efficiency. Background Art

[0002] In a wound tube heat exchanger, within the space between the wound core and the shell, the heat exchange tubes are alternately wound in a spiral shape, and spacer strips of a certain shape are used to separate the layers to keep a certain distance. Since the heat transfer elements of the existing wound tube heat exchangers are ordinary round tubes, when the fluid medium flows between the outer walls of the upper and lower tubes adjacent axially in the same layer of heat exchange tubes, there will be some stagnant areas and vortices with relatively low flow velocities. The flow velocity here is much smaller than that in the main flow area between the layers of heat exchange tubes, resulting in a decrease in the local heat transfer coefficient, and the vortices formed in the stagnant areas will greatly increase the pressure drop caused when the fluid medium flows through the shell side, increasing the pump work of the heat exchanger under normal operating conditions.

[0003] Therefore, improved heat exchanger tube cores and heat exchangers for improving heat exchange efficiency are needed. Summary of the Invention

[0004] The object of the present invention is to provide a heat exchanger tube core and a heat exchanger that at least partially solve the above problems.

[0005] According to one aspect of the present invention, there is provided a heat exchange tube, including a hollow tube body of the heat exchange tube extending in the longitudinal direction, and a heat exchange tube inlet and a heat exchange tube outlet at both ends of the hollow tube body of the heat exchange tube. At least a part of the hollow tube body of the heat exchange tube in the middle between both ends of the hollow tube body of the heat exchange tube has a non-circular cross-section intercepted perpendicular to the tube axis, and the width of the non-circular cross-section is greater than the height; wherein, the part of the hollow tube body of the heat exchange tube in the middle between both ends having a non-circular cross-section is wound into a spiral shape around a central axis, and the width direction of the cross-section of the spiral-wound part of the heat exchange tube is parallel to the direction of the central axis.

[0006] By using a heat exchange tube with a non-circular cross-section and making the width direction of the cross-section of the non-circular cross-section heat exchange tube parallel to the central axis direction of the heat exchanger, that is, making the width direction of the cross-section of the non-circular cross-section heat exchange tube parallel to the fluid medium flow direction, it is possible to reduce the flow resistance of the fluid medium and the post-tube stagnant area corresponding to the flow direction, and increase the heat exchange area, thereby improving the heat exchange efficiency of the heat exchange tube wound into a spiral shape.

[0007] Preferably, the inner cavity of the hollow tube body of the heat exchange tube includes a support member extending in the longitudinal direction for maintaining the inner cavity of the hollow tube body of the heat exchange tube.

[0008] Setting a support member in the hollow tube body of the heat exchange tube with a non-circular cross-section can prevent the heat exchange tube with a non-circular cross-section from deforming and twisting during the spiral winding process.

[0009] Preferably, the support member is at least one support tube, and the support tube includes a hollow tube body of the support tube and a support tube inlet and a support tube outlet at both ends of the hollow tube body of the support tube. The length of the support tube is greater than or equal to the length of the heat exchange tube.

[0010] Setting the support member in the hollow tube body of the heat exchange tube with a non-circular cross-section as a support tube can, on the one hand, prevent the heat exchange tube with a non-circular cross-section from deforming and twisting during the spiral winding process. On the other hand, due to the difference in the cross-sectional areas of the support tube and the heat exchange tube lumen, the same medium flows at different flow rates in them, resulting in different heat exchange amounts and temperature differences, thereby causing heat exchange between the fluid medium in the support tube and the fluid medium in the heat exchange tube, further enhancing heat transfer and improving the heat exchange efficiency.

[0011] Preferably, at least a part of the side of the cross-section of the support tube along the width direction of the non-circular cross-section coincides with the side of the width direction of the non-circular cross-section.

[0012] The support tube can be a hollow tube with any cross-sectional shape, as long as its cross-sectional shape can at least partially coincide with the side of the width direction of the non-circular cross-section along the width direction of the non-circular cross-section and play a supporting role.

[0013] Preferably, the ratio of the width to the height of the non-circular cross-section is not less than 2:1, and the sides in the width direction of the non-circular cross-section are parallel straight line segments.

[0014] A heat exchange tube with a ratio of the width to the height of the non-circular cross-section not less than 2:1 is more conducive to reducing the resistance of the fluid medium, the retention area, and increasing the heat exchange area. Moreover, a heat exchange tube with parallel straight line segments on the sides in the width direction of the non-circular cross-section is easier to manufacture.

[0015] According to another aspect of the present invention, there is provided a heat exchanger tube core, including an upper tube sheet and a lower tube sheet, the upper tube sheet and the lower tube sheet respectively including through holes; a winding core body connecting the centers of the upper tube sheet and the lower tube sheet; and a heat exchange tube layer wound around the winding core body as the central axis. At least one heat exchange tube is included in one heat exchange tube layer. The upper and lower end portions of the heat exchange tube respectively pass through the through holes in the upper tube sheet and the lower tube sheet and are hermetically connected thereto. The heat exchange tubes in the same heat exchange tube layer are wound with the same spiral radius and spiral angle. Among them, at least one of the heat exchange tubes includes the heat exchange tube with the non-circular cross-section described above.

[0016] By manufacturing the heat exchanger tube core with heat exchange tubes having high heat exchange efficiency, the heat exchanger tube core obtained also has high heat exchange efficiency.

[0017] Preferably, a heat exchange tube layer includes a plurality of heat exchange tubes, and the plurality of heat exchange tubes further includes heat exchange tubes with a circular cross-section. The outer diameter of the heat exchange tubes with a circular cross-section is the same as the height of the heat exchange tubes with a non-circular cross-section.

[0018] Manufacturing a heat exchanger tube core with heat exchange tubes of different cross-sectional shapes can form turbulence between different heat exchange tubes, strengthen the convective heat transfer effect, and thus improve the heat exchange efficiency. Heat exchange tubes with different cross-sectional shapes and the same height are more conducive to the winding arrangement of heat exchange tubes and the support between heat exchange tubes during the manufacturing process.

[0019] Preferably, the at least one heat exchange tube layer is a plurality of heat exchange tube layers, and the heat exchange tubes of at least one or more heat exchange tube layers close to the winding core are heat exchange tubes with a circular cross-section.

[0020] Compared with heat exchange tubes with a non-circular cross-section height equal to the outer diameter of a circular cross-section, the bending strength of heat exchange tubes with a non-circular cross-section is better than that of heat exchange tubes with a circular cross-section. Heat exchange tubes with a circular cross-section have a smaller minimum bending radius. Therefore, setting the heat exchange tubes of the heat exchange tube layer close to the winding core as heat exchange tubes with a circular cross-section having a smaller minimum bending radius is more conducive to the manufacture of the heat exchanger tube core.

[0021] Preferably, the heat exchange tube layer with heat exchange tubes having a circular cross-section and the heat exchange tube layer with heat exchange tubes having a non-circular cross-section are arranged at intervals.

[0022] Since using heat exchange tubes of different shapes between different heat exchange tube layers is easy to form turbulence between the heat exchange tube layers, it can strengthen the convective heat transfer effect and further improve the heat exchange efficiency.

[0023] Preferably, a spacer is provided between the layers of the plurality of heat exchange tube layers. The spacer is used to maintain the relative positions of the heat exchange tubes between the layers of the plurality of heat exchange tube layers and between the individual spirals of the spiral portions of the heat exchange tubes in each layer. The spacer is uniformly arranged along the circumferential direction of the winding core or the heat exchange tube layer and has teeth extending between the individual spirals of the heat exchange tubes.

[0024] The spacer according to the present invention can not only maintain the relative positions of the heat exchange tubes between the heat exchange tube layers but also maintain and support the heat exchange tubes between the spirals of the heat exchange tubes.

[0025] Preferably, the winding directions of the heat exchange tubes of the odd-numbered layers and the even-numbered layers of the plurality of heat exchange tube layers are opposite, and the lengths of the heat exchange tubes are substantially the same.

[0026] The opposite helical winding directions of the heat exchange tubes in the odd layers and even layers of multiple heat exchange tube layers can generate turbulence between the odd layers and even layers, further improving the turbulence effect of the flow of the second fluid medium, forming turbulence, enhancing the convective heat transfer effect, and the substantially identical lengths of the heat exchange tubes can ensure that the pressure drops of the fluid mediums inside the heat exchange tubes are substantially the same.

[0027] Preferably, the heat exchange tubes are divided into multiple groups, and different groups among the multiple groups of heat exchange tubes flow the same or different fluid mediums as required.

[0028] Introducing different fluid mediums into the heat exchange tubes can make the heat exchanger tube core applicable to more heat exchange occasions and meet different requirements.

[0029] Preferably, the heat exchange tubes sequentially include a straight tube section and a transition tube section between the upper tube sheet or the lower tube sheet and the helical part of the heat exchange tubes.

[0030] The arrangement of the straight tube section is conducive to the installation and fixation of the heat exchange tubes, and the transition tube section can prevent the heat exchange tubes from being overly bent and deformed.

[0031] According to another aspect of the present invention, there is provided a heat exchanger, including: a housing extending longitudinally, including a first fluid medium inlet, a first fluid medium outlet, a second fluid medium inlet, a second fluid medium outlet, and a heat exchanger tube core as described above disposed inside the housing, a first fluid medium inlet, a heat exchange tube inlet, a hollow inner cavity of the heat exchange tube, a heat exchange tube outlet, and a first fluid medium outlet form a first fluid medium channel, a second fluid medium inlet, an inner gap of the housing, and a second fluid medium outlet form a second fluid medium channel, the first fluid medium channel and the second fluid medium channel are sealed and isolated, and the first fluid medium in the first fluid medium channel and the second fluid medium in the second fluid medium channel are arranged to be able to perform heat exchange through the tube wall of the heat exchange tubes.

[0032] Preferably, the heat exchange tubes of the heat exchanger tube core sequentially include a straight tube section and a transition tube section between the upper tube sheet or the lower tube sheet and the helical part of the heat exchange tubes, and the second medium inlet and the second medium outlet are correspondingly arranged on the housing at positions corresponding to the straight tube section.

[0033] In summary, according to the heat exchange tubes, the heat exchanger tube core, and the heat exchanger of the present invention, by using heat exchange tubes with non-circular cross-sections and making the width direction of the non-circular cross-section of the heat exchange tubes parallel to the central axis direction of the heat exchanger, that is, making the width direction of the non-circular cross-section of the heat exchange tubes parallel to the fluid medium flow direction, it is possible to reduce the flow resistance of the fluid medium and the post-tube retention area in the corresponding flow direction, increase the heat exchange area, and thereby improve the heat exchange efficiency. Description of the Drawings

[0034] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments read in conjunction with the accompanying drawings:

[0035] Figure 1 is a schematic perspective view of a wound tube heat exchanger according to the present invention;

[0036] Figure 2 is a partial cross-sectional front view of a heat exchanger according to a first embodiment of the present invention and a partial enlarged cross-sectional view showing the arrangement of heat exchange tubes;

[0037] Figure 3 is along Figure 2 a cross-sectional view taken along section C-C in;

[0038] Figure 4 , Figure 5 , Figure 6 and Figure 7 are Figure 2 and Figure 3 examples of different cross-sectional shapes of non-circular cross-section heat exchange tubes in the embodiments shown in;

[0039] Figure 8 is a partial cross-sectional front view of a wound tube heat exchanger according to a second embodiment of the present invention and a partial enlarged cross-sectional view showing the arrangement of heat exchange tubes;

[0040] Figure 9 is a partial cross-sectional front view of a wound tube heat exchanger according to a third embodiment of the present invention and a partial enlarged cross-sectional view showing the arrangement of heat exchange tubes;

[0041] Figure 10 is a partial cross-sectional front view of a wound tube heat exchanger according to a fourth embodiment of the present invention and a partial enlarged cross-sectional view showing the arrangement of heat exchange tubes;

[0042] Figure 11 is a schematic perspective view of a wound tube heat exchanger according to a fifth embodiment of the present invention. Detailed Embodiments

[0043] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only for explaining the relevant invention and are not intended to limit the invention. Additionally, it should be noted that for the sake of description, only parts related to the invention are shown in the drawings.

[0044] In the present invention, the orientation or positional relationship indicated by terms such as "upper", "lower", "inner", "outer", "center", "longitudinal", etc. is based on the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe the present invention and its embodiments, and are not intended to limit that the indicated devices, elements or components must have a specific orientation, or be constructed and operated in a specific orientation.

[0045] Figure 1 FIG. 4 is a schematic perspective view of a wound tube heat exchanger according to a first embodiment of the present invention, in which the housing body is shown in a transparent manner for showing the internal structure.

[0046] The heat exchanger is generally shown by reference numeral 100. The heat exchanger 100 includes a housing 101 and a heat exchanger core 102 disposed inside the housing 101. The housing 101 extends longitudinally and includes a first fluid medium inlet 111 and a first fluid medium outlet 112, as well as a second fluid medium inlet 114 and a second fluid medium outlet 113. The heat exchanger core 102 includes an upper tube sheet 122 and a lower tube sheet 123. The upper tube sheet 122 and the lower tube sheet 123 respectively include through holes (not labeled); a winding core 124 connecting the centers of the upper tube sheet 122 and the lower tube sheet 123; and a heat exchange tube layer wound around the winding core 124 as the center. At least one heat exchange tube 121 is included in one heat exchange tube layer. For clarity of illustration in the figure, only two heat exchange tubes 121 are schematically shown. The upper and lower ends of the heat exchange tube 121 respectively pass through the through holes in the upper tube sheet 122 and the lower tube sheet 123 and are hermetically connected thereto. The heat exchange tubes 121 in the same heat exchange tube layer are wound with the same spiral radius and spiral angle.

[0047] The first fluid medium inlet 111, the hollow inner cavity of the heat exchange tube, and the first fluid medium outlet 112 form a first fluid medium channel. The second fluid medium inlet 114, the internal gap of the housing, and the second fluid medium outlet 113 form a second fluid medium channel. The first fluid medium channel and the second fluid medium channel are hermetically isolated, and are arranged such that the first fluid medium in the first fluid medium channel and the second fluid medium in the second fluid medium channel can perform heat exchange through the tube wall of the heat exchange tube 121.

[0048] The heat exchanger tube core 102 is formed by successively winding heat exchange tube layers around the winding core 124. When winding each heat exchange tube layer, first determine the number, winding angle, and winding direction of the heat exchange tubes 121 in this heat exchange tube layer. The winding angles, winding directions, and winding radii of the heat exchange tubes 121 in the same heat exchange tube layer are the same, and there is a certain gap between adjacent heat exchange tubes 121 along the central axis direction to ensure the heat exchange effect. Then wind the adjacent outer heat exchange tube layers, and it is also necessary to determine the number, winding angle, and winding direction of the heat exchange tubes in this adjacent outer heat exchange tube layer. Usually, the number of the heat exchange tubes 121 in the heat exchange tube layer is determined according to the heat exchange requirements, and the number of the heat exchange tubes 121 is also restricted by actual physical conditions, such as the radius of the heat exchange tubes, the pitch size of the heat exchange tube helix, etc. The winding directions of adjacent heat exchange tube layers are opposite, which can further improve the turbulence effect of the flow of the second fluid medium, form turbulence, thin and destroy the medium boundary layer on the outer wall of the heat exchange tubes 121, achieve a better enhanced convective heat transfer effect than winding in the same direction, and at the same time increase the stability of the heat exchange tube 121 tube bundle to avoid oscillation under the action of the flow of the second fluid medium. The lengths of the heat exchange tubes 121 in different heat exchange tube layers are basically the same, thereby ensuring that the pressure drops of the fluid media in the heat exchange tubes 121 are basically the same.

[0049] The heat exchange tubes 121 successively include straight pipe sections and transition pipe sections between the upper tube sheet 122 or the lower tube sheet 123 and the helical part of the heat exchange tubes 121. The two ends are straight pipe sections, which are used to facilitate passing through the through holes on the upper tube sheet 122 and the lower tube sheet 123, and the part between the helical part and the straight pipe section is the transition section. The setting of the straight pipe sections is beneficial to the installation and fixation of the heat exchange tubes 121, and the transition pipe sections can avoid excessive bending deformation of the heat exchange tubes 121. The second fluid medium inlet 114 and the second fluid medium outlet 113 are arranged on the shell 101 corresponding to the positions of the straight pipe sections.

[0050] Figure 2 is Figure 1 is a partial cross-sectional front view of the heat exchanger shown in and a partial enlarged cross-sectional view showing the arrangement of the heat exchange tubes. In the figure, the heat exchanger shell 101 is normally shown as non-transparent, and is partially sectioned to show the winding structure of the heat exchanger tube core 102. Figure 2 The circular part in the partially sectioned part of the heat exchanger shell 101 in is shown in a partial enlarged cross-sectional view, which shows the arrangement of the heat exchange tube layers in the heat exchanger tube core 102 and the arrangement of the heat exchange tubes 121 in the heat exchange tube layers, and more specifically shows that the heat exchange tubes 121 in the heat exchanger tube core 102 have non-circular cross-sections.

[0051] Combined Figure 1 and Figure 2, it can be seen that the heat exchange tube 121 includes a hollow tube body of the heat exchange tube extending in the longitudinal direction, and a heat exchange tube inlet 1211 and a heat exchange tube outlet (not shown) at both ends of the hollow tube body of the heat exchange tube. At least a part of the hollow tube body of the heat exchange tube 121 in the middle between both ends of the hollow tube body of the heat exchange tube has a non-circular cross-section intercepted perpendicular to the tube axis, and the width of the non-circular cross-section is greater than the height. Among them, the part of the hollow tube body of the heat exchange tube 121 in the middle between both ends with a non-circular cross-section is wound into a spiral around a center (shown in the figure as winding around the winding core 124), and the width direction of the cross-section of the spiral part of the heat exchange tube (that is, the part of the heat exchange tube with a spiral) is parallel to the central axis direction, specifically as Figure 2 shown in the partial enlarged cross-sectional view in

[0052] In this embodiment, the first fluid medium is introduced from the first fluid medium inlet 111 and flows out from the first fluid medium outlet 112, and the second fluid medium is introduced from the second fluid medium inlet 114 and flows out from the second fluid medium outlet 113. Thus, it can be seen that the spiral part of the heat exchange tube 121 is set such that the width direction of its non-circular cross-section is parallel to the central axis direction, that is, the width direction of the cross-section is set to be parallel to the flow direction of the second fluid medium. That is to say, the end of the non-circular cross-section of the spiral part of the heat exchange tube 121 in the width direction faces the flow direction of the second fluid medium. In this way, since the width of the non-circular cross-section of the heat exchange tube 121 is greater than the height, compared with a heat exchange tube with a circular cross-section having the same perimeter, when the second fluid medium passes through the spiral part of the heat exchange tube 121, it has a smaller resistance and a smaller retention area. Therefore, the heat exchange tube 121 with a non-circular cross-section improves the effective heat exchange flow rate, increases the effective heat exchange area, and is more conducive to spatial arrangement, with a higher space utilization rate, and can reduce the volume and weight of the heat exchanger. Thus, the heat exchange efficiency of the heat exchange tube 121 with a non-circular cross-section wound into a spiral, the heat exchanger tube core 102 including it, and the heat exchanger 100 can be improved.

[0053] Figure 3 is a cross-sectional view taken along Figure 2 section C-C in Figure 3 and Figure 2In the enlarged partial cross-sectional view shown in a circle, it can be seen that gaskets 125 are arranged between the heat exchange tube layers of the heat exchanger tube core 102. The gaskets 125 are used to ensure the relative position between the multiple heat exchange tube layers, that is, to ensure the gap along the radial direction of the heat exchange tube layers. At the same time, the gaskets 125 also have teeth 1251 extending into the gaps along the axial direction between the heat exchange tubes 121 in the adjacent heat exchange tube layers, that is, the teeth 1251 extend between the spirals of the spiral part of the heat exchange tube 121 in each layer to ensure the axial gap between the spirals of the heat exchange tube 121 in the same heat exchange layer. It can be seen that the gaskets 125 can prevent the oscillation of the heat exchange tubes 121 caused by the flow of the second fluid medium, which makes the axial gap and radial gap between the heat exchange tubes 121 uneven, thereby reducing the heat exchange efficiency.

[0054] Continuing to refer to 3, the figure also shows that the gaskets 125 are evenly arranged between the heat exchange tube layers along the circumferential direction of the heat exchange tube layers to form a gasket layer. In this embodiment, four gaskets 125 are arranged in each gasket layer, and the gasket layers are staggered along the radial direction of the heat exchange tube layer, preferably at an angle of 45°, to ensure uniform heat exchange and avoid the gaskets 125 located in the same radial direction from obstructing the flow of the second fluid medium.

[0055] Figure 4 , Figure 5 , Figure 6 and Figure 7 yes Figure 1 , Figure 2 and Figure 3 Examples of different non-circular cross-sections of the heat exchange tube 121 of the embodiment shown in FIG. The non-circular cross-section of the heat exchange tube 121 with a non-circular cross-section according to this embodiment of the present invention may be Figure 4 The rectangular cross section shown in Figure 5 The rectangular cross section with rounded corners shown in Figure 6 The wavy flat section shown in , or Figure 7 The support tube 1213 shown in FIG. 1 has a rectangular circular cross-section.

[0056] The non-circular cross-section of the non-circular cross-section heat exchange tube 121 according to the first embodiment of the present invention is not limited to Figures 4 - 7 As shown in , any cross section with a width greater than a height is applicable to the non-circular cross-section heat exchange tube 121 according to an embodiment of the present invention, and preferably the ratio of the width to the height of the non-circular cross section is not less than 2: 1. Preferably, the sides of the width direction of the non-circular cross section are parallel straight line segments, so that the non-circular cross-section heat exchange tube is easy to process.

[0057] Figure 7The support tube 1213 shown in the figure includes a hollow tube body of the support tube and a support tube inlet and a support tube outlet at both ends of the hollow tube body of the support tube. The length of the support tube 1213 is greater than or equal to the length of the heat exchange tube 121. The setting of the support tube 1213 can not only prevent the heat exchange tube 121 with a non-circular cross-section from deforming and twisting during the spiral winding process, but also, due to the difference in the cross-sectional areas of the tube cavities of the support tube 1213 and the heat exchange tube 121, the same medium flows through them at different flow rates, resulting in a temperature difference due to different heat exchange amounts, thereby causing heat exchange between the fluid medium in the support tube 1213 and the fluid medium in the heat exchange tube 121, enhancing the convective heat transfer performance and improving the heat exchange efficiency.

[0058] The number of the support tubes 1213 is not limited to one and can be multiple. The cross-section of the support tube 1213 is not limited to Figure 7 the circular cross-section shown in the figure. It can be a support tube whose cross-section at least partially coincides with the side in the width direction of the non-circular cross-section of the heat exchange tube 121 along the width direction of the non-circular cross-section of the heat exchange tube 121 and plays a supporting role. The support tube 1213 is not limited to the circular cross-section support tube shown in the figure either. It can be any form of support member without a hollow tube body between the sides in the width direction of the cross-section of the heat exchange tube 121, which is used to maintain the inner cavity of the hollow tube body of the heat exchange tube and prevent the heat exchange tube 121 from being distorted and deformed during the winding process around the aforementioned winding core 124, thereby affecting the flow area of the fluid medium in the heat exchange tube 121.

[0059] Figure 2 、 Figure 3 、 Figure 4 、 Figure 5 、 Figure 6 and Figure 7 In the heat exchange tube 121 of the embodiment described in the figure, all use heat exchange tubes with non-circular cross-sections. This embodiment can make full use of the advantages of heat exchange tubes with non-circular cross-sections and improve the heat exchange efficiency of the heat exchange tubes, the heat exchanger core, and the heat exchanger.

[0060] According to the principle of the present invention, compared with a wound tube heat exchanger with heat exchange tubes having circular cross-sections, using at least one heat exchange tube with a non-circular cross-section to replace the heat exchange tube with a circular cross-section will improve the heat exchange efficiency of the original heat exchanger core and the heat exchanger. Moreover, by adopting different combined arrangements of heat exchange tubes with non-circular cross-sections and heat exchange tubes with circular cross-sections, there will be other advantages. For example, the minimum winding radius of the heat exchange tube with a circular cross-section is small. Using heat exchange tubes with circular cross-sections in the inner heat exchange tube layer is more convenient for winding; arranging the heat exchange tubes with circular cross-sections and the heat exchange tubes with non-circular cross-sections alternately will generate turbulence between the heat exchange tubes, promoting heat exchange.

[0061] Next, reference will be made to Figure 8 、Figure 9 and Figure 10 Examples are described that employ different combined arrangements of heat exchange tubes having non-circular cross-sections and heat exchange tubes having circular cross-sections.

[0062] Figure 8 FIG. 7 is a partial cross-sectional front view of a wound tube heat exchanger 200 according to a second embodiment of the present invention and a partially enlarged cross-sectional view showing the arrangement of the heat exchange tubes. The same components as in the first embodiment are denoted by the same reference numerals. For the sake of distinction, the first digit of the reference numeral is increased by 1. The parts identical to those in the first embodiment will not be described in detail.

[0063] The difference between this embodiment and the first embodiment lies only in the heat exchange tubes and their arrangement. The heat exchange tubes are generally denoted by 221. The heat exchange tubes having non-circular cross-sections are denoted by reference numeral 221a, and the heat exchange tubes having circular cross-sections are denoted by reference numeral 221b.

[0064] Referring to Figure 8 the partially enlarged cross-sectional view shown in FIG. 15 and circled, it is shown that all the heat exchange tubes in the heat exchange tube layer closest to the winding core 224 are heat exchange tubes 221b having circular cross-sections, while all the heat exchange tubes in the outer heat exchange tube layer are heat exchange tubes 221a having non-circular cross-sections. The height of the heat exchange tubes 221a having non-circular cross-sections is the same as the outer diameter of the heat exchange tubes 221b having circular cross-sections, for convenient winding arrangement.

[0065] Comparing the heat exchange tubes 221a having non-circular cross-sections and the heat exchange tubes 221b having circular cross-sections with the same height and outer diameter, the bending strength of the heat exchange tubes 221a having non-circular cross-sections is higher than that of the heat exchange tubes 221b having circular cross-sections. Therefore, the minimum winding radius of the heat exchange tubes 221b having circular cross-sections is small. Using the heat exchange tubes 221b having circular cross-sections in the inner heat exchange tube layer is more convenient for winding, while using the heat exchange tubes 221a having non-circular cross-sections in the remaining heat exchange tube layers reduces the retention area and resistance of the second fluid medium, increases the heat exchange area, and improves the heat exchange efficiency of the heat exchanger core 202 and the heat exchanger 200.

[0066] Figure 8 In the heat exchanger 200 according to the second embodiment shown, only the innermost heat exchange tube layer uses the heat exchange tubes 221b having circular cross-sections, and the remaining heat exchange tube layers use the heat exchange tubes 221a having non-circular cross-sections. The present invention is not limited to this embodiment. It is also possible to use the heat exchange tubes 221b having circular cross-sections in multiple inner layers and the heat exchange tubes 221a having non-circular cross-sections in the remaining heat exchange tube layers.

[0067] Figure 9FIG. 0 is a partial cross-sectional front view of a wound tube heat exchanger 300 according to a third embodiment of the present invention and a partial enlarged cross-sectional view showing the arrangement of heat exchange tubes. Components identical to those in the first embodiment in this embodiment are denoted by the same reference numerals. For distinction, the first digit of the reference numerals is increased by 2. Parts identical to those in the first embodiment will not be described in detail.

[0068] The difference between this embodiment and the first embodiment lies only in the heat exchange tubes and their arrangement. The heat exchange tubes are generally denoted by 321. The heat exchange tubes with non-circular cross-sections are denoted by reference numeral 321a, and the heat exchange tubes with circular cross-sections are denoted by reference numeral 321b.

[0069] Referring to Figure 9 the partial enlarged cross-sectional view shown by a circle in FIG., it is shown that all the heat exchange tubes in the heat exchange tube layer closest to the winding core 324 are heat exchange tubes 321b with circular cross-sections, and then successively from the inside to the outside, they are alternately arranged with the heat exchange tube layers all having non-circular cross-section heat exchange tubes 321a.

[0070] This third embodiment is not only more convenient to manufacture because the innermost layer uses heat exchange tubes 321b with circular cross-sections, and secondly, because it uses heat exchange tubes 321a with non-circular cross-sections, thereby reducing the retention area and resistance of the second fluid medium, increasing the heat exchange area, and improving the heat exchange efficiency of the heat exchanger core 302 and the heat exchanger 300. Moreover, because heat exchange tubes with different shapes are used between different heat exchange tube layers, it is easy to form turbulence between the heat exchange tube layers, which can strengthen the convective heat transfer effect, so the heat exchange efficiency is further improved.

[0071] Figure 10 FIG. 15 is a partial cross-sectional front view of a wound tube heat exchanger 400 according to a fourth embodiment of the present invention and a partial enlarged cross-sectional view showing the arrangement of heat exchange tubes. Components identical to those in the first embodiment in this embodiment are denoted by the same reference numerals. For distinction, the first digit of the reference numerals is increased by 3. Parts identical to those in the first embodiment will not be described in detail.

[0072] The difference between this embodiment and the first embodiment lies only in the heat exchange tubes and their arrangement. The heat exchange tubes are generally denoted by 421. The heat exchange tubes with non-circular cross-sections are denoted by reference numeral 421a, and the heat exchange tubes with circular cross-sections are denoted by reference numeral 421b.

[0073] Referring to Figure 10 the partial enlarged cross-sectional view shown by a circle in FIG., it is shown that in each heat exchange tube layer, the heat exchange tubes 421b with circular cross-sections and the heat exchange tubes 421a with non-circular cross-sections are alternately arranged, so that turbulence is formed not only between the heat exchange tube layers but also between different heat exchange tubes in the same heat exchange tube layer.

[0074] In this fourth embodiment, not only is the retention area and resistance of the second fluid medium reduced, the heat transfer area increased, and the heat transfer efficiency of the heat exchanger core 402 and the heat exchanger 400 improved due to the use of the heat exchange tube 421a with a non-circular cross-section, but also the convective heat transfer effect can be enhanced because turbulent flows are formed between the heat exchange tube layers and between different heat exchange tubes in the same heat exchange tube layer due to the use of heat exchange tubes with different shapes in the same heat exchange tube layer, thereby further improving the heat transfer efficiency.

[0075] Figure 11 FIG. is a schematic perspective view of a wound tube heat exchanger 500 according to a fifth embodiment of the present invention. The same components as in the first embodiment are denoted by the same reference numerals, and for the sake of distinction, the first digit of the reference numerals is increased by 4. The parts that are the same as in the first embodiment will not be described in detail.

[0076] The difference between this embodiment and the first embodiment is that the housing 501 further includes a third fluid medium inlet 515 and a third fluid medium outlet 516, whereby the heat exchange tubes 521 are divided into two groups, one group for circulating the first fluid medium and the other group for circulating the third fluid medium to meet different heat transfer requirements.

[0077] Specifically, Figure 11 as schematically shown in FIG., the heat exchange tube inlet 5213 and the heat exchange tube outlet 5214 located in the inner layer are in fluid communication with the first fluid medium inlet 511 and the first fluid medium outlet 512 respectively, and the heat exchange tube inlet 5211 and the heat exchange tube outlet 5212 located in the outer layer are in fluid communication with the third fluid medium inlet 515 and the third fluid medium outlet 516 respectively.

[0078] Compared with the first to fourth embodiments, the fifth embodiment is applicable to heat exchangers with three fluid media and has a wider application range. It can also be configured as a heat exchanger applicable to multiple fluid media as needed, such as for large-sized wound tube heat exchangers.

[0079] In summary, since a retention area with a relatively low flow velocity will be formed behind the tube when the second fluid medium flows through the heat exchange tube, affecting the heat transfer effect, and in addition, the vortices formed in this area are also the main factors causing the kinetic energy loss of the second fluid medium, the heat exchange tube according to the present invention reduces the retention area and the kinetic energy loss caused by this area, thereby reducing the pressure drop during the flow of the second medium, effectively thinning the flow boundary layer and the thermal boundary layer on the outer wall of the heat exchange tube, thus improving the heat transfer performance of the heat exchange tube, the heat exchanger core using this heat exchange tube, and the heat exchanger, and further improving the heat transfer efficiency. The present invention is particularly applicable to high-efficiency heat transfer with a small temperature difference.

[0080] The above description is only a preferred embodiment of the present application and an explanation of the applied technical principles. Those skilled in the art should understand that the scope of the invention involved in the present application is not limited to the technical solution formed by the specific combination of the above technical features, and should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the technical solution formed by mutually replacing the above features with the technical features (but not limited to) disclosed in the present application that have similar functions.

Claims

1. A heat exchanger tube core, comprising an upper tube sheet and a lower tube sheet, the upper tube sheet and the lower tube sheet respectively including through holes; a winding core body connecting the centers of the upper tube sheet and the lower tube sheet; and a heat exchange tube layer wound around the winding core body as the center. At least one heat exchange tube is included in one heat exchange tube layer, and the upper and lower end portions of the heat exchange tube respectively pass through the through holes in the upper tube sheet and the lower tube sheet and are hermetically connected thereto. The heat exchange tubes in the same heat exchange tube layer are wound with the same spiral radius and spiral angle. Among them, at least one of the heat exchange tubes includes a heat exchange tube hollow body extending in the longitudinal direction and a heat exchange tube inlet and a heat exchange tube outlet at both ends of the heat exchange tube hollow body. The heat exchange tube hollow body has a non-circular cross-section intercepted perpendicular to the tube axis at least in the middle part between both ends of the heat exchange tube hollow body, and the width of the non-circular cross-section is greater than the height; among them, the part with a non-circular cross-section in the middle of both ends of the heat exchange tube hollow body is wound into a spiral shape around a central axis, and the width direction of the cross-section of the spiral part of the heat exchange tube is parallel to the direction of the central axis, the heat exchange tube layer is a plurality of heat exchange tube layers, and the heat exchange tubes in at least one or more heat exchange tube layers close to the winding core body are heat exchange tubes with circular cross-sections.

2. The heat exchanger tube core according to claim 1, wherein, The inner cavity of the heat exchange tube hollow body includes a support member extending in the longitudinal direction for maintaining the inner cavity of the heat exchange tube hollow body.

3. The heat exchanger tube core according to claim 2, wherein, The support member is at least one support tube, and the support tube includes a support tube hollow body and a support tube inlet and a support tube outlet at both ends of the support tube hollow body. The length of the support tube is greater than or equal to the length of the heat exchange tube.

4. The heat exchanger tube core according to claim 3, wherein, At least part of the side of the cross-section of the support tube along the width direction of the non-circular cross-section coincides with the side of the width direction of the non-circular cross-section.

5. The heat exchanger tube core according to claim 1, wherein, The ratio of the width to the height of the non-circular cross-section is not less than 2:1, and the sides in the width direction of the non-circular cross-section are parallel straight line segments.

6. The heat exchanger tube core according to claims 1-5, wherein, One heat exchange tube layer includes multiple heat exchange tubes, and the multiple heat exchange tubes further include heat exchange tubes with circular cross-sections. The outer diameter of the heat exchange tubes with circular cross-sections is the same as the height of the heat exchange tubes with non-circular cross-sections.

7. The heat exchanger tube core according to claims 1-5, wherein, The heat exchange tube layers with heat exchange tubes having circular cross-sections and the heat exchange tube layers with heat exchange tubes having non-circular cross-sections are arranged at intervals.

8. The heat exchanger tube core according to claims 1-5, wherein, Gaskets are provided between the layers of the multiple heat exchange tube layers. The gaskets are used to maintain the relative positions of the heat exchange tubes between the layers of the multiple heat exchange tube layers and between the spirals of the spiral parts of the heat exchange tubes in each layer. The gaskets are evenly arranged along the circumferential direction of the winding core body or the heat exchange tube layer and have teeth extending between the various spirals of the heat exchange tubes.

9. The heat exchanger tube core according to claims 1-5, wherein, The spiral winding directions of the heat exchange tubes in the odd-numbered layers and the even-numbered layers of the multiple heat exchange tube layers are opposite, and the lengths of the heat exchange tubes are basically the same.

10. The heat exchanger tube core according to claims 1-5, wherein, The heat exchange tubes are divided into multiple groups, and different groups among the multiple groups of heat exchange tubes flow the same or different fluid media as required.

11. The heat exchanger tube core according to claims 1-5, wherein, The heat exchange tubes successively include straight tube sections and transition tube sections between the upper tube sheet or the lower tube sheet and the spiral parts of the heat exchange tubes.

12. A heat exchanger, comprising: A housing, extending longitudinally, includes a first fluid medium inlet, a first fluid medium outlet, a second fluid medium inlet, a second fluid medium outlet, and a heat exchanger tube core as described in any one of claims 1-11 disposed within the housing. The first fluid medium inlet, the hollow inner cavity of the heat exchange tube, and the first fluid medium outlet form a first fluid medium passage. The second fluid medium inlet, the internal gap of the housing, and the second fluid medium outlet form a second fluid medium passage. The first fluid medium passage and the second fluid medium passage are sealed and isolated, and are arranged such that the first fluid medium in the first fluid medium passage and the second fluid medium in the second fluid medium passage can perform heat exchange through the tube wall of the heat exchange tube.

13. The heat exchanger according to claim 12, wherein, The heat exchange tubes of the heat exchanger tube core sequentially include a straight tube section and a transition tube section between the upper tube sheet or the lower tube sheet and the helical portion of the heat exchange tube. The second fluid medium inlet and the second fluid medium outlet are correspondingly arranged on the housing at positions corresponding to the straight tube section.

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