Heat exchange tube and air conditioning system

Abstract

The utility model provides a heat exchange tube and an air conditioning system. The heat exchange tube comprises a tube body; a fin; and a protruding structure. According to the heat exchange tube and the air conditioning system, the portions, away from the tube body, of the fins are inclined to form the inclined sections, the surfaces of the inclined sections and the surfaces of the fins are not located on the same plane, the surface tension of condensation liquid on the side faces of the fins can be changed, and compared with the side faces, located on the same plane, of the fins in the prior art, the surface tension of the condensation liquid can be changed. According to the heat exchange tube, the first groove structures and the protruding structures are arranged, so that a liquid film can be thinned, the heat exchange efficiency of the heat exchange tube can be improved, the bottoms of the pocket structures formed by the first groove structures and the protruding structures are not parallel to the tube body position where the fins are located, and condensate can further rapidly fall off; the problem that the heat transfer efficiency is affected due to the fact that a pocket structure formed in the prior art enables condensation liquid to be gathered at the bottom is solved, efficient condensation can be promoted, and the heat exchange efficiency of the heat exchange pipe can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of heat exchange equipment, in particular to a heat exchange tube and an air conditioning system. Background Art

[0002] There are two ways of the condensation process, dropwise condensation and filmwise condensation. For dropwise condensation, current technologies use means such as spraying and ionization to change the surface energy of the metal to achieve it, but this method has problems such as low sustainability and is not conducive to applications in the industrial refrigeration field. While filmwise condensation is based on strengthening the "Gregorig" effect, thinning the condensate film and reducing the thermal resistance. It has been widely used in industry and has become the main heat transfer enhancement method in industrial applications.

[0003] In the existing heat exchange tubes, generally, a notched structure is formed at the top of the fin by using a knurling die at the top of the fin and a raised structure is formed on both sides of the fin side. The raised structure and the notched structure not only increase the heat exchange area but also have a positive impact on the condensation process. However, the raised structure and the notched structure intersect to form a pocket structure. Due to the influence of capillary force, the condensate condensed at the top of the fin preferentially accumulates in the pocket structure, hindering the contact between the saturated steam and the fin and further condensation. Moreover, when the refrigerant condensate of a common flat fin condenses at the top of the fin, the fin is almost perpendicular to the tube wall and the liquid-phase partial pressure difference on both sides of the fin is relatively small, resulting in the condensate on the fin not being able to be quickly and significantly thinned, seriously affecting the heat exchange performance of the heat exchange tube. Summary of the Utility Model

[0004] In order to solve the technical problem that the fin shape of the heat exchange tube in the existing technology affects the heat exchange performance, a heat exchange tube and an air conditioning system are provided, in which the fin is bent to form an inclined section, and a first groove structure and a raised structure are arranged on the inclined section to promote the detachment of the condensate to improve the heat exchange efficiency.

[0005] A heat exchange tube includes:

[0006] A tube body;

[0007] Fins, the fins are arranged on the outer wall of the tube body, and a flow channel is formed between two adjacent fins;

[0008] The part of the fin away from the tube body is bent towards one side of the fin to form an inclined section, a first groove structure is arranged on the inclined section, and two adjacent flow channels are communicated through the first groove structure;

[0009] A raised structure, the raised structure is arranged on at least one side surface of the inclined section, and the raised structure is located at the bottom of the first groove structure.

[0010] The convex structure has a top surface facing away from the tube body. The top surface is connected to the bottom surface of the first groove structure, and the bottom surface of the first groove structure is in the same plane as the top surface; or, the top surface is a curved surface, and along the direction away from the connection position between the top surface and the first groove structure, the top surface is bent towards the tube body relative to the first groove structure.

[0011] The inclined section has opposite first and second side surfaces. The first side surface is located on the side of the second side surface away from the tube body, and the convex structures are provided on both the first side surface and the second side surface.

[0012] The convex height of the convex structure on the first side surface is less than the convex height of the convex structure on the second side surface.

[0013] The inclined section has a first side surface facing away from the tube body, and a second groove structure is provided on the first side surface.

[0014] The central axis of the second groove structure has a first included angle with the central axis of the tube body, and the angular range of the first included angle is 85° to 89.9°.

[0015] Along the direction away from the inclined section, the thickness of the convex structure gradually decreases.

[0016] Along the direction towards the tube body, the thickness of the inclined section gradually increases.

[0017] Along the direction towards the tube body, the width of the first groove structure gradually decreases.

[0018] The fin also has a straight plate section. The inclined section is arranged on the tube body through the straight plate section. The inclined section has a first side surface facing away from the tube body, and the included angle β between the plane where the first side surface is located and the plane where the straight plate section is located has a numerical range of β≤48°.

[0019] The maximum thickness of the fin is less than the width of the flow channel.

[0020] Internal tooth structures are provided on the inner wall of the tube body.

[0021] An air conditioning system includes the above heat exchange tube.

[0022] The heat exchange tube and the air conditioning system provided by the present utility model form an inclined section by inclining the part of the fin away from the tube body, so that the surface of the inclined section and the surface of the fin are not in the same plane. The surface tension of the condensate on the side surface of the fin will change. Compared with the side surface of the fin in the same plane in the prior art, it can promote the thinning of the liquid film, thereby improving the heat exchange efficiency of the heat exchange tube. Moreover, the bottom of the pocket structure formed by the first groove structure and the protrusion structure is not parallel to the position of the tube body where the fin is located, which can further make the condensate fall off quickly, avoiding the problem that the pocket structure formed in the prior art will cause the condensate to accumulate at the bottom and affect the heat transfer efficiency, and can promote the efficient occurrence of condensation and improve the heat exchange efficiency of the heat exchange tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a perspective view of the flattened state of the heat exchange tube provided by an embodiment of the present utility model;

[0024] Figure 2 is a schematic structural view of the flattened state of the heat exchange tube provided by an embodiment of the present utility model;

[0025] Figure 3 is another schematic structural view of the flattened state of the heat exchange tube provided by an embodiment of the present utility model;

[0026] Figure 4 is another schematic structural view of the flattened state of the heat exchange tube provided by an embodiment of the present utility model;

[0027] In the figure:

[0028] 1, tube body; 2, fin; 3, flow channel; 21, inclined section; 22, first groove structure; 23, protrusion structure; 24, second groove structure; 4, internal tooth structure. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] In order to make the objectives, technical solutions and advantages of the present utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0030] In order to enable those skilled in the art to better understand the solution of the present utility model, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0031] It should be noted that in the description of the specification and claims of the present utility model and the above-mentioned drawings, the terms "first", "second", etc. are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that such terms can be interchanged under appropriate circumstances for the embodiments of the present utility model described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0032] It should be noted that in the description of the present utility model, the terms indicating directions or positional relationships such as "upper", "lower", "left", "right", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings. This is only for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0033] In addition, it should also be noted that in the description of the present utility model, unless otherwise clearly specified and defined, the terms "installation", "setting", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and can also be the communication inside two elements. For those skilled in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0034] Heat transfer occurs in many engineering technologies, especially in the fields of chemical engineering and refrigeration and air conditioning. In the condensers used in refrigeration and air conditioning, heat is transferred from the medium on the side with a higher temperature to the medium on the other side. The heat exchange tubes in the condenser not only need to consider efficient heat exchange but also are pressure-bearing components that play a partition role, separating the two media inside and outside the tubes. The heat transfer process should be that heat always transfers from the side with a higher temperature to the side with a lower temperature. However, when heat is transferred through the heat exchange tubes, there is always a certain resistance, and this resistance is called the heat transfer resistance. The total transfer resistance is the sum of the resistance inside the tube, outside the tube, the tube wall, and the fouling resistance. To improve the heat transfer efficiency, materials with relatively high thermal conductivity such as copper and stainless steel are generally used for processing to reduce the thermal resistance of the tube wall material. The phase change heat transfer outside the tube improves the heat transfer by improving the structure of the heat transfer surface to reduce the thermal resistance outside the tube. Inside the tube, measures such as increasing the turbulence intensity inside the tube and increasing the area are taken to reduce the thermal resistance inside the tube.

[0035] In the prior art, heat exchange tubes generally form a notch structure at the top of the fins by using a knurling die at the top of the fins and a raised structure on both sides of the fin side. The raised structure and the notch structure not only increase the heat exchange area but also have a positive impact on the condensation process. However, the raised structure and the notch structure extend along the tube axis and circumferentially, forming a curved surface with two protrusions on both sides of the fin. The raised structure protrudes into the gap between adjacent fins, and each radially extending protrusion has an intersection line with the notch, so that a pocket structure can be formed at the top of the fin. Due to the influence of capillary force, the condensate condensed at the top of the fin preferentially accumulates in the pocket structure, hindering the contact between the saturated steam and the fin and further condensation. Moreover, when the common three-dimensional fin refrigerant condensate condenses at the top of the fin, the fin is almost perpendicular to the tube wall, and the liquid phase partial pressure difference on both sides of the fin is relatively small, resulting in the condensate not being able to quickly and significantly thin on the fin, seriously affecting the heat exchange performance of the heat exchange tube.

[0036] For this reason, the present application provides a heat exchange tube as Figures 1 to 4 shown, including: a tube body 1; fins 2, the fins 2 are arranged on the outer wall of the tube body 1, and a flow channel 3 is formed between two adjacent fins 2; a part of the fin 2 away from the tube body 1 is bent towards one side of the fin 1 to form an inclined section 21, and a first groove structure 22 is arranged on the inclined section 21, and two adjacent flow channels 3 are communicated through the first groove structure 22; a raised structure 23, the raised structure 23 is arranged on at least one side surface of the inclined section 21, and the raised structure 23 is located at the bottom of the first groove structure 22. By inclining the part of the fin 2 away from the tube body 1 to form the inclined section 21, the surface of the inclined section 21 is not in the same plane as the surface of the fin 2, and the surface tension of the condensate on the side surface of the fin 2 will change. Compared with the side surface of the fin 2 in the same plane in the prior art, it can promote the thinning of the liquid film, thereby improving the heat exchange efficiency of the heat exchange tube. Moreover, the bottom of the pocket structure formed by the first groove structure 22 and the raised structure 23 is not parallel to the position of the tube body 1 where the fin 2 is located, which can further make the condensate fall off quickly, avoiding the problem that the pocket structure formed in the prior art will cause the condensate to accumulate at the bottom and affect the heat transfer efficiency, and can promote efficient condensation and improve the heat exchange efficiency of the heat exchange tube.

[0037] As an implementation manner, the convex structure 23 has a top surface away from the pipe body 1, the top surface is connected to the bottom surface of the first groove structure 22, and the bottom surface of the first groove structure 22 and the top surface are in the same plane, that is, the convex structure 23 is located below the bottom surface of the first groove structure 22, which can avoid the convex structure 23 from hindering the fluid flowing in the first groove structure 22. At the same time, since the first groove structure 22 is arranged on the inclined section 21, the bottom surface of the first groove structure 22 is also inclined, that is, the convex structure 23 is also inclined at this time, so that the bottom of the pocket structure formed by the convex structure 23 is not parallel to the position of the pipe body 1 where the fin 2 is located, and the condensate falls off as soon as possible under the action of gravity, making the condensation occur efficiently.

[0038] As another implementation manner, the difference from the previous implementation manner is that the top surface is a curved surface, and along the direction away from the connection position between the top surface and the first groove structure 22, the top surface is curved towards the pipe body relative to the first groove structure 22. By setting the top surface as a curved surface, the non-parallel degree between the bottom of the pocket structure and the pipe body 1 is further increased, thereby further increasing the effect of the condensate falling off.

[0039] As Figure 1 As shown, the inclined section 21 has opposite first side surface and second side surface, the first side surface is located on the side of the second side surface away from the pipe body 1, and the convex structure 23 is arranged on both the first side surface and the second side surface. By arranging the convex structure 23 on both the first side surface and the second side surface, the heat exchange area of the fin 2 is further increased. At the same time, the convex structure 23 on the second side surface protrudes into the flow channel 3, which can better drain the condensate into the flow channel 3, improve the rate of the condensate leaving the fin 2. At the same time, due to the action of gravity, the amount of condensate generated by the convex structure 23 on the first side surface is less than the amount of condensate generated by the convex structure 23 on the second side surface. Therefore, the protruding height of the convex structure 23 on the first side surface can be less than the protruding height of the convex structure 23 on the second side surface, reducing the processing material amount of the fin 2 and reducing the production cost, and also avoiding the convex structure 23 on the first side surface from shielding the upper opening of the flow channel 3, ensuring the heat exchange efficiency of the heat exchange tube. Preferably, the top surface of the convex structure 23 on the first side surface, the top surface of the convex structure 23 on the second side surface and the bottom surface of the first groove structure 22 are in smooth transition.

[0040] The inclined section 21 has a first side surface away from the tube body 1, and a second groove structure 24 is arranged on the first side surface. By using the second groove structure 24, the surface area of the first side surface is increased, thereby improving the heat exchange efficiency of the fin 2. Moreover, the second groove structure 24 can further utilize the capillary suction effect of the groove to further thin the liquid film on the first side surface, thereby reducing the heat exchange resistance of the fin 2 and improving the heat exchange efficiency of the fin 2. Preferably, the cross-sectional shape of the second groove structure 24 is arc-shaped or rectangular to ensure the capillary suction effect of the second groove structure 24, and further ensure the heat exchange efficiency of the heat exchange tube. Preferably, the central axis of the second groove structure 24 and the central axis of the tube body 1 have a first included angle, and the angle range of the first included angle is 85° to 89.9°, which can increase the heat exchange area of the tube body 1 and is convenient for processing the fin by an extrusion process. During the extrusion process, it advances spirally, and the first included angle is the deflection angle during the processing.

[0041] Along the direction away from the inclined section 21, the thickness of the convex structure 23 gradually decreases. The thickness at the connection position between the convex structure 23 and the inclined section 21 is the largest, which can ensure the connection reliability between the convex structure 23 and the inclined section 21. At the same time, gradually reducing the thickness of the convex structure 23 can reduce the obstruction and occlusion of the flow area of the flow channel 3 by the convex structure 23, ensure that the condensate in the flow channel 3 can flow smoothly along the flow channel 3, and also ensure that the gaseous working medium enters the flow channel 3 and directly contacts and exchanges heat with the surface of the tube body 1, further improving the heat exchange efficiency of the heat exchange tube.

[0042] Along the direction close to the tube body 1, the thickness of the inclined section 21 gradually increases. By using the thickness change of the inclined section 21, the surface tension on the side surface of the fin 2 can increase gradiently, thereby increasing the difference in the curvature radius of the condensate on the inclined section 21. At the same time, the difference in the surface tension on the two side surfaces of the fin 2 will also increase, further promoting the thinning of the liquid film, reducing the heat exchange resistance of the fin 2, and improving the heat exchange efficiency of the fin 2. As Figure 2 shown, the thickness b at the top of the inclined section 21 is less than the thickness a at the bottom of the inclined section 21.

[0043] Along the direction close to the tube body 1, the width of the first groove structure 22 gradually decreases. By utilizing the change in the width of the first groove structure 22, the side width of the inclined section 21 between two adjacent first groove structures 22 also changes. Similarly, the surface tension on the side surface of the fin 2 can increase in a gradient manner, thereby increasing the difference in the curvature radius of the condensate on the inclined section 21. At the same time, the difference in the surface tension on the two side surfaces of the fin 2 also increases, further promoting the thinning of the liquid film, reducing the heat transfer resistance of the fin 2, and improving the heat transfer efficiency of the fin 2. Preferably, the cross-section of the first groove structure 22 is triangular, inverted trapezoidal, etc., which is convenient for processing the first groove structure 22 and can also ensure the reliable change in the width of the first groove structure 22. When the cross-section of the first groove structure 22 is triangular, the tangent plane where the vertex at the lowest end of the triangle is located constitutes the bottom surface of the first groove structure 22, and this tangent plane is in the same plane as the top surface; or, this tangent plane is tangent to the top surface at the connection position.

[0044] Preferably, the fin further has a straight plate section. The inclined section 22 is arranged on the tube body through the straight plate section. The inclined section 22 has a first side surface far from the tube body 1, and the numerical range of the included angle β between the plane where the first side surface is located and the plane where the straight plate section is located is β ≤ 48°. This avoids the excessive inclination degree of the inclined section 21 from overly shielding the upper opening of the flow channel 3, ensuring that the gaseous working medium enters the flow channel 3 and directly contacts and exchanges heat with the surface of the tube body 1, and further improving the heat transfer efficiency of the heat exchange tube.

[0045] The maximum thickness of the fin 2 is less than the width of the flow channel 3, ensuring that the condensate in the flow channel 3 can flow smoothly, avoiding the accumulation of condensate in the flow channel 3 and affecting the heat transfer efficiency of the outer surface of the tube body 1, and thus improving the overall heat transfer efficiency of the heat exchange tube.

[0046] The inner wall of the tube body 1 is provided with an internal tooth structure 4, which is used to increase the heat transfer area of the inner wall of the heat exchange tube, enhance the heat transfer efficiency of the working medium flowing inside the tube body 1, and can also increase the structural strength of the heat exchange tube and improve the structural reliability of the heat exchange tube. Preferably, the internal tooth structure 4 is a spiral tooth distributed in a multi-start spiral along the axis direction. The spiral tooth makes the working medium inside the tube body 1 flow spirally, which can not only increase the flow distance of the working medium inside the tube body 1, but also increase the contact ability between the working medium and the inner wall of the tube body 1 by using the centrifugal force generated during the spiral flow process, thereby improving the heat transfer efficiency of the heat exchange tube. Among them, the internal tooth structure 4 is processed by rolling and spinning techniques, which can solve the production cost of the heat exchange tube without increasing the manufacturing materials of the heat exchange tube. Optionally, the fins 2 are arranged in a straight line on the outer surface of the tube body 1, so as to form a flow channel parallel to the central axis of the tube body 1 on the outer surface of the tube body 1. At this time, the channel inside the tube body 1 formed by the internal tooth structure 4 does not coincide with the flow channel 3 formed outside the tube body 1 by the fins 2, thereby effectively improving the heat transfer efficiency of the heat exchange tube.

[0047] An air conditioning system includes the above heat exchange tube.

[0048] The above embodiments only represent several implementation manners of the present invention, and the description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the appended claims.

Claims

1. A heat exchange tube, characterized in that: include: tube body(1); Fins (2), the fins (2) being arranged on the outer wall of the tube body (1), and a flow channel (3) being formed between two adjacent fins (2); The portion of the fin (2) away from the tube body (1) is bent toward one side of the fin (2) to form an inclined section (21), and a first groove structure (22) is provided on the inclined section (21), and two adjacent flow channels (3) are connected through the first groove structure (22); A protruding structure (23), wherein the protruding structure (23) is arranged on at least one side surface of the inclined section (21), and the protruding structure (23) is located at the bottom of the first groove structure (22).

2. The heat exchange tube according to claim 1, characterized in that: The protrusion structure (23) has a top surface away from the tube body (1), the top surface is connected to the bottom surface of the first groove structure (22), and the bottom surface of the first groove structure (22) and the top surface are in the same plane; or, the top surface is a curved surface, and along a direction away from the connection position between the top surface and the first groove structure (22), the top surface is bent relative to the first groove structure (22) in a direction close to the tube body (1).

3. The heat exchange tube according to claim 1, characterized in that: The inclined section (21) has a first side surface and a second side surface that are opposite to each other, the first side surface is located on a side of the second side surface that is away from the tube body (1), and the protruding structure (23) is provided on both the first side surface and the second side surface.

4. The heat exchange tube according to claim 3, characterized in that: The protrusion height of the protrusion structure (23) on the first side surface is smaller than the protrusion height of the protrusion structure (23) on the second side surface.

5. The heat exchange tube according to claim 1, characterized in that: The inclined section (21) has a first side surface away from the tube body (1), and a second groove structure (24) is provided on the first side surface.

6. The heat exchange tube according to claim 5, characterized in that: The central axis of the second groove structure (24) and the central axis of the tube body (1) have a first angle, and the angle range of the first angle is 85° to 89.9°.

7. The heat exchange tube according to claim 1, characterized in that: Along the direction away from the inclined section (21), the thickness of the protruding structure (23) gradually decreases.

8. The heat exchange tube according to claim 1, characterized in that: The thickness of the inclined section (21) gradually increases in a direction approaching the tube body (1).

9. The heat exchange tube according to claim 1, characterized in that: Along the direction approaching the tube body (1), the width of the first groove structure (22) gradually decreases.

10. The heat exchange tube according to claim 1, characterized in that: The fin also has a straight plate section, the inclined section is arranged on the tube body (1) through the straight plate section, the inclined section (21) has a first side surface away from the tube body (1), and the value range of the angle β between the plane where the first side surface is located and the plane where the straight plate section is located is β≤48°.

11. The heat exchange tube according to claim 1, characterized in that: The maximum thickness of the fin (2) is smaller than the width of the circulation channel (3).

12. The heat exchange tube according to claim 1, characterized in that: The inner wall of the tube body (1) is provided with an inner tooth structure (4).

13. An air conditioning system, characterized in that: The heat exchange tube comprises the heat exchange tube according to any one of claims 1 to 12.

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