Heat exchange tubes, heat exchangers and air conditioning equipment

Abstract

This invention provides a heat exchange tube, a heat exchanger, and an air conditioning device. The heat exchange tube includes a tube body, outer fins, and a grooved structure. The heat exchange tube, heat exchanger, and air conditioning device provided by this invention, by setting an installation groove on the top of the outer fins and setting a grooved structure within the installation groove, can increase the heat exchange area of ​​the outer fins and optimize the heat conduction path. Furthermore, the shape of the grooved structure can be used to adjust the shape of the top of the outer fins, overcoming the problems of fluid stagnation and "bridging" on the surface of the outer fins in existing technologies. This improves the convective heat transfer coefficient and the degree of fluid turbulence, effectively increasing the heat exchange efficiency of the heat exchange tube.

Description

Technical Field

[0001] This utility model relates to the field of heat exchange technology, and in particular to a heat exchange tube, a heat exchanger, and an air conditioning device. Background Technology

[0002] In existing condensing heat exchange equipment, the condenser tube is a core component, and its heat transfer performance directly affects the efficiency of the entire system. Currently, the widely used condenser tube structures mainly include smooth tubes, straight finned tubes, and some heat exchange tubes with internal turbulence structures. However, these traditional structures generally suffer from problems such as insufficient heat transfer efficiency, high refrigerant film thermal resistance, and easy refrigerant retention between fins in practical applications.

[0003] Specifically, traditional smooth tubes suffer from limited heat transfer area and a thick fluid boundary layer between the inside and outside of the tube, resulting in a low overall heat transfer coefficient that fails to meet the demands of high-efficiency heat exchange. To address this issue, existing technologies have introduced improved solutions by incorporating fins on the outer wall, such as linear or helical fin structures. While finned structures can increase the heat transfer area to some extent, limitations in fin shape and arrangement can lead to localized stagnation or uneven heat transfer as the fluid flows between the fins, resulting in limited improvement in heat transfer performance.

[0004] Furthermore, in terms of fin structure design, most existing fins are continuous structures, lacking an effective mechanism for refrigerant film disturbance. Fluid tends to stagnate and "bridge" on the fin surface, reducing condensation heat transfer efficiency. Although some technologies attempt to disrupt the boundary layer by setting cuts or segmented structures on the fins, these designs often fail to achieve a good synergistic effect with fluid flow characteristics, severely affecting the heat transfer efficiency of the heat exchange tube. Utility Model Content

[0005] To address the technical problem of low heat exchange efficiency in existing heat exchange tubes, a heat exchange tube, heat exchanger, and air conditioning equipment are provided that features a grooved structure on the top of the outer fins to enhance turbulence and heat exchange effects.

[0006] A heat exchange tube, comprising:

[0007] tube body;

[0008] The outer fin is disposed on the outer wall of the tube body, and the outer fin has a first edge away from the tube body, the first edge being recessed in the direction of the tube body to form a mounting groove;

[0009] A groove-shaped structure is provided at the mounting groove, and the groove opening of the groove-shaped structure faces away from the pipe body.

[0010] The maximum outer diameter of the groove structure is greater than the thickness of the outer fin, and the groove structure protrudes at least partially from the outer fin.

[0011] The groove structure is shaped like a spherical cap or a bowl, with the top of the spherical cap or the top of the bowl abutting against the bottom surface of the mounting groove.

[0012] The cross-sectional dimensions of the groove structure gradually increase in the direction away from the tube body.

[0013] The slot is circular in shape, and the relationship between the diameter d of the slot and the height h1 of the outer fin is: 0.16≤d / h1≤0.87; or, the diameter d of the slot is in the range of 0.05mm to 1.3mm.

[0014] The groove structure is provided with a slit gap, which extends from the groove opening of the groove structure toward the pipe body.

[0015] The relationship between the depth h3 of the slit gap and the height h2 of the groove structure is: 0.03≤h3 / h2≤1; or, the depth h3 of the slit gap ranges from 0.02mm to 0.65mm.

[0016] The relationship between the width h4 of the slit gap and the height h2 of the groove structure is: 0.38≤h4 / h2≤1; or, the width of the slit gap is in the range of 0.05mm to 0.2mm.

[0017] The sidewall of the groove structure and the sidewall of the outer fin have an included angle α, the angle α being in the range of 15° to 75°.

[0018] The height of the groove structure is less than or equal to the depth of the mounting groove.

[0019] The relationship between the height h2 of the groove structure and the height h1 of the outer fin is 0.03≤h2 / h1≤0.43; or, the height h2 of the groove structure ranges from 0.05mm to 0.65mm.

[0020] The heat exchange tube includes at least two auxiliary fins. The first end of the auxiliary fin is located at the bottom surface of the mounting groove, and the second end extends away from the tube body. All the auxiliary fins together form the groove structure.

[0021] The slot of the groove structure has a slit gap opening towards the top of the groove structure, and there is a gap between two adjacent auxiliary fins, the gap forming the slit gap.

[0022] The spacing ranges from 0 mm to 0.2 mm.

[0023] There is a gap between two adjacent auxiliary fins, and the gap gradually increases along the direction from the first end to the second end of the auxiliary fin.

[0024] The angle α between the line connecting the first and second ends of the auxiliary fin and the sidewall of the outer fin ranges from 15° to 75°.

[0025] There is a clearance between two adjacent groove structures, and the clearance ranges from 0.05 mm to 1.1 mm.

[0026] Along the length direction of the outer fins, the circumferential clearance s1 between two adjacent groove structures ranges from 0.1 mm to 1.1 mm; and / or, along the axial direction of the heat exchange tube, the axial clearance s2 between two adjacent groove structures ranges from 0.05 mm to 1 mm.

[0027] The heat exchange tube has internal teeth on its inner wall.

[0028] The outer fins are spirally arranged on the outer wall of the tube, and the spiral angle of the outer fins ranges from 0.2° to 2.5°.

[0029] A heat exchanger comprising the heat exchange tubes described above.

[0030] An air conditioning device includes the aforementioned heat exchange tube or heat exchanger.

[0031] The heat exchange tube, heat exchanger, and air conditioning equipment provided by this utility model, by setting an installation groove on the top of the outer fins and setting a groove-shaped structure within the installation groove, can increase the heat exchange area of ​​the outer fins and optimize the heat conduction path. Furthermore, the shape of the groove-shaped structure can be used to adjust the shape of the top of the outer fins, maximizing the liquid phase pressure at the top of the fluid. This increases the pressure difference between the top and root of the outer fins, promoting refrigerant flow towards the root of the outer fins. Additionally, the groove opening edge can cut the liquid film, resulting in uneven liquid film distribution. By reducing the average thermal resistance ("Gregorig effect"), the problem of fluid stagnation and "bridging" on the surface of the outer fins in existing technologies is overcome. Moreover, the shape of the groove structure can be matched with the spiral arrangement of the outer fins. The fluid flowing spirally through the outer fins can generate local eddies in the groove structure, further enhancing the turning point of the fluid when it flows through the groove structure. The surface tension effect promotes the refrigerant to flow faster, reduces the thermal resistance of the heat exchange tube, improves the convective heat transfer coefficient and the degree of fluid turbulence, and effectively improves the heat exchange efficiency of the heat exchange tube. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of the heat exchange tube provided in an embodiment of the present utility model;

[0033] Figure 2 This is another structural schematic diagram of the heat exchange tube provided in an embodiment of the present utility model;

[0034] Figure 3 This is another structural schematic diagram of the heat exchange tube provided in an embodiment of the present utility model;

[0035] Figure 4 This is another structural schematic diagram of the heat exchange tube provided in an embodiment of the present utility model;

[0036] Figure 5 A schematic diagram of the structure of the heat exchange tube with a slit gap width of 0 mm provided in this embodiment of the utility model;

[0037] Figure 6 Another structural schematic diagram of the heat exchange tube provided in this embodiment of the present invention when the width of the slit gap is 0mm;

[0038] Figure 7 A schematic diagram of the structure when the depth of the slit gap in the heat exchange tube reaches its maximum, as provided in this embodiment of the utility model;

[0039] Figure 8 Another structural schematic diagram showing the maximum depth of the slit gap in the heat exchange tube provided in this embodiment of the utility model;

[0040] Figure 9 Another structural schematic diagram showing the maximum depth of the slit gap in the heat exchange tube provided in this embodiment of the utility model;

[0041] Figure 10 This is a performance comparison chart of the external heat transfer coefficient ho of this utility model and the prior art;

[0042] Figure 11 This is a performance comparison chart of the total heat transfer coefficient Uo of this utility model and the prior art;

[0043] In the picture:

[0044] 1. Tube body; 2. Outer fins; 3. Groove structure; 31. Slot gap; 32. Auxiliary fins; 4. Inner teeth. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of this 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 for explaining this utility model and are not intended to limit this utility model.

[0046] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0047] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate for the embodiments of the utility model described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0048] It should be noted that in the description of this utility model, the terms "upper," "lower," "left," "right," "inner," and "outer," which indicate directional or positional relationships, are based on the directional or positional relationships shown in the accompanying drawings. These are merely for ease of description and do not indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0049] Furthermore, it should be noted that, in the description of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "setting," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection, an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0050] In existing condensing heat exchange equipment, the condenser tube is a core component, and its heat transfer performance directly affects the efficiency of the entire system. Currently, the widely used condenser tube structures mainly include smooth tubes, straight finned tubes, and some heat exchange tubes with internal turbulence structures. However, these traditional structures generally suffer from problems such as insufficient heat transfer efficiency, high refrigerant film thermal resistance, and easy refrigerant retention between fins in practical applications.

[0051] Specifically, traditional smooth tubes suffer from limited heat transfer area and a thick fluid boundary layer between the inside and outside of the tube, resulting in a low overall heat transfer coefficient that fails to meet the demands of high-efficiency heat exchange. To address this issue, existing technologies have introduced improved solutions by incorporating fins on the outer wall, such as linear or helical fin structures. While finned structures can increase the heat transfer area to some extent, limitations in fin shape and arrangement can lead to localized stagnation or uneven heat transfer as the fluid flows between the fins, resulting in limited improvement in heat transfer performance.

[0052] Furthermore, in terms of fin structure design, most existing fins are continuous structures, lacking an effective mechanism for refrigerant film disturbance. Fluid tends to stagnate and "bridge" on the fin surface, reducing condensation heat transfer efficiency. Although some technologies attempt to disrupt the boundary layer by setting cuts or segmented structures on the fins, these designs often fail to achieve a good synergistic effect with fluid flow characteristics, severely affecting the heat transfer efficiency of the heat exchange tube.

[0053] Therefore, this application provides a method such as Figures 1 to 11 The heat exchange tube shown includes: a tube body 1; an outer fin 2, which is disposed on the outer wall of the tube body 1 and has a first edge away from the tube body 1, the first edge being recessed towards the tube body 1 to form a mounting groove; and a groove structure 3, which is disposed at the mounting groove and has its groove opening facing away from the tube body 1. By setting a mounting groove on the top of the outer fin 2 and setting the groove structure 3 within the mounting groove, the heat exchange area of ​​the outer fin 2 can be increased and the heat conduction path optimized. Furthermore, the shape of the groove structure 3 can be used to adjust the top shape of the outer fin 2, allowing the liquid phase pressure at the top of the fluid to reach its maximum value, increasing the pressure difference between the top and root of the outer fin 2, and promoting refrigerant flow towards the root of the outer fin 2. Additionally, the groove opening edge of the groove structure 3 can cut the liquid film, resulting in a non-uniform distribution of the liquid film and reducing the average thermal resistance ("G"). The "regorig effect" overcomes the problem of fluid stagnation and "bridging" on the surface of the outer fin 2 in the prior art. Moreover, the shape of the groove structure 3 can match the spiral arrangement of the outer fin 2. The fluid flowing spirally through the outer fin 2 can generate local vortices in the groove structure 3, further enhancing the turning point of the fluid when it flows through the groove structure 3. The surface tension effect promotes the refrigerant to flow faster, reduces the thermal resistance of the heat exchange tube, improves the convective heat transfer coefficient and the degree of fluid turbulence, and effectively improves the heat exchange efficiency of the heat exchange tube.

[0054] By recessing the top of the outer fin 2 to form an installation groove, the outer diameter of the heat exchange tube can be avoided after installing the groove structure 3. The installation groove can also be used to reliably fix the groove structure 3, ensuring the structural reliability of the heat exchange tube.

[0055] Preferably, the groove structure 3 can be formed by processing the outer fins 2. The top of the outer fins 2 is extruded and formed by a preset tool. At this time, the extruded part of the outer fins 2 will be recessed towards the tube body 1 to form the mounting groove. At the same time, the extruded part will move to both sides of the outer fins 2 to form the groove structure 3. This method will not increase the weight of the heat exchange tube, does not require additional groove structure 3, and does not require fixed connection between the groove structure 3 and the outer fins 2, effectively optimizing production efficiency and improving the structural reliability of the heat exchange tube.

[0056] like Figure 1 As shown, the maximum outer diameter of the groove structure 3 is greater than the thickness of the outer fin 2. The groove structure 3 protrudes at least partially from the outer fin 2. Specifically, the width of the groove structure 3 is greater than the thickness of the outer fin 2. Part of the groove structure 3 is located on the first side of the outer fin 2, and part of the groove structure 3 is located on the second side of the outer fin 2. That is, the groove structure 3 protrudes outward from both sides of the outer fin 2, but the groove structures 3 do not contact each other. The size of the groove structure 3 can be fully utilized to increase the heat exchange area of ​​the outer fin 2. It can also use two adjacent groove structures 3 to block the upper part of the spiral flow channel formed at the root of the outer fin 2 to a certain extent. The protruding effect of this blocking enhances the surface tension of the fluid, increases the pressure difference between the top and root of the outer fin 2, and promotes the flow of refrigerant to the root of the outer fin 2. This overcomes the problem of fluid stagnation and "bridging" on the surface of the outer fin 2 in the prior art, and further improves the heat exchange efficiency of the heat exchange tube.

[0057] In particular, when the trough structure 3 is formed directly on the heat exchange tube, the squeezed part can deform to both sides of the outer fin 2. At this time, it is only necessary to guide the deformation, which reduces the difficulty of controlling the deformed part of the outer fin 2, effectively optimizes production efficiency, and improves the structural reliability of the heat exchange tube.

[0058] In one embodiment, the groove structure 3 is bowl-shaped, with the top of the bowl abutting against the bottom surface of the mounting groove. The bowl-shaped top refers to the reliable flow guidance of fluid through the top of the outer fins 2 using the groove structure 3, reliably generating local eddies within the groove structure 3. This further enhances the deflection of the fluid as it flows through the groove structure 3, utilizing surface tension to accelerate refrigerant flow, reduce the thermal resistance of the heat exchange tube, increase the convective heat transfer coefficient and the degree of fluid turbulence, effectively improving the heat exchange efficiency of the heat exchange tube. The shape of the mounting groove is the same as the outer wall shape of the groove structure 3, ensuring a reliable and fixed connection between the groove structure 3 and the mounting groove.

[0059] Along the direction away from the tube body 1, the cross-sectional dimensions of the groove structure 3 gradually increase. This maximizes the cross-sectional area of ​​the groove structure 3 at the groove opening, ensuring that the fluid can smoothly enter and flow into the groove structure 3, thus improving the heat exchange efficiency. It also allows the fluid to flow smoothly out of the groove structure 3, preventing the fluid from being blocked by the groove opening and affecting its flow, thereby further ensuring the heat exchange efficiency of the heat exchange tube.

[0060] In another embodiment, the groove structure 3 is shaped like a spherical cap. A spherical cap is formed by cutting a sphere with a plane, resulting in two spherical caps. The cross-section formed on the sphere during the cutting process constitutes the groove of the spherical cap, and a straight line perpendicular to this cross-section and passing through the center of the sphere forms the top of the spherical cap. Compared to a bowl shape, the spherical cap shape is more regular, making the design of the heat exchanger tubes faster. Furthermore, for the scheme of forming the groove structure 3 by extrusion, the design difficulty of the structure used to extrude the outer fins 2 is reduced, which is beneficial to the design and production of the heat exchanger tubes.

[0061] Preferably, the height of the spherical segment is not greater than the radius of the sphere corresponding to the spherical segment, so that the cross-sectional area of ​​the groove structure 3 at the groove opening is maximized. This ensures that the fluid can smoothly enter the groove structure 3 for diversion, thus ensuring the improvement of the heat exchange efficiency of the groove structure 3. It also allows the fluid to flow smoothly out of the groove structure 3, avoiding the fluid being blocked by the groove opening and affecting the flow of the fluid, thereby further ensuring the heat exchange efficiency of the heat exchange tube.

[0062] like Figure 2 As shown, the groove is circular in shape. The relationship between the diameter d of the groove and the height h1 of the outer fin 2 is: 0.16≤d / h1≤0.87. That is, the diameter of the groove is limited according to the height h1 of the outer fin 2. Under the premise of ensuring that there is no interference between the groove structures 3, the size of the groove structure 3 can be limited according to the range of the d / h1 ratio, which facilitates the design of the groove structure 3. Specifically, when the d / h1 ratio is too large, structural interference or "bridging" will inevitably occur between the groove structures 3. When the d / h1 ratio is too small, the volume of the groove structure 3 relative to the outer fin 2 is too small and its influence on the fluid is small, which will also affect the heat exchange efficiency of the heat exchange tube. Only when 0.16≤d / h1≤0.87 can the influence of the groove structure 3 on the fluid be guaranteed and the "bridging" phenomenon be avoided, thus ensuring the heat exchange efficiency of the heat exchange tube.

[0063] Optionally, the diameter d of the slot is in the range of 0.05 mm to 1.3 mm. In this embodiment, the number of outer fins 2 per inch along the axial direction of the heat exchange tube is 11 to 60, that is, the distance between two adjacent outer fins 2 in the axial direction of the heat exchange tube is in the range of 0.42 mm to 2.3 mm. If the diameter d of the slot is too large, structural interference will occur between two adjacent slot structures 3, making it impossible to process the slot structure 3, and also causing a "bridging" phenomenon between the outer fins 2, affecting the heat exchange efficiency of the heat exchange tube; if the diameter d of the slot is too small, the influence of the slot structure 3 on the fluid will be small, which will also affect the heat exchange efficiency of the heat exchange tube. Only when the diameter d of the slot is in the range of 0.05 mm to 1.3 mm can the influence of the slot structure 3 on the fluid be guaranteed and the "bridging" phenomenon be avoided, thus ensuring the heat exchange efficiency of the heat exchange tube.

[0064] Furthermore, the groove structure 3 is provided with a slit gap 31, which extends from the groove opening of the groove structure 3 toward the tube body 1. By providing the slit gap 31 on the groove structure 3, the sharp edges and sharp points on the groove structure 3 are increased, enhancing the effect of piercing the liquid film, allowing the metal outer fins 2 to effectively contact the refrigerant vapor, and further improving the heat exchange effect.

[0065] Wherein, the depth h3 of the slit gap 31 refers to the height value of the crack shape formed along the shape of the groove structure 3 from the groove opening to the top of the groove structure 3. The relationship between the depth h3 of the slit gap 31 and the height h2 of the groove structure 3 is: 0.03≤h3 / h2≤1. That is, the depth h3 of the slot gap 31 can be designed according to the height h2 of the slot structure 3, which facilitates the design of the slot structure 3. Specifically, when h3 / h2 equals 1, it means that the slot structure 3 is completely divided into at least two parts. At this time, the parts of the slot structure 3 are relatively independent and the structural reliability is low. When h3 / h2 is less than 0.03, the depth of the slot gap 31 is too small, the size of the sharp edge formed on the slot structure 3 is small, the ability to pierce the liquid film is reduced, and the heat exchange efficiency of the heat exchange tube cannot be effectively improved. Only when 0.03≤h3 / h2≤1 can the improvement of the slot gap 31's ability to pierce the liquid film of the slot structure 3 be guaranteed. At the same time, the liquid film retention and "bridging" phenomenon generated in the slot gap 31 are weakened, which can effectively improve the "Gregorig" effect, thereby achieving the purpose of improving the heat exchange efficiency of the heat exchange tube.

[0066] Optionally, the depth h3 of the slit gap 31 ranges from 0.02mm to 0.65mm. When the depth h3 of the slit gap 31 is too large, it will reduce the structural strength of the trough structure 3. Moreover, in this embodiment, the maximum dimension of the height h2 of the trough structure 3 is 0.65mm, and the depth h3 of the slit gap 31 cannot exceed the height h2 of the trough structure 3. When the depth h3 of the slit gap 31 is too small, the size of the sharp edge formed on the trough structure 3 is small, the ability to pierce the liquid film is reduced, and the heat exchange efficiency of the heat exchange tube cannot be effectively improved. Only when the depth h3 of the slit gap 31 is within the range of 0.02mm to 0.65mm can the ability of the slit gap 31 to pierce the liquid film of the trough structure 3 be guaranteed. At the same time, the liquid film retention and "bridging" phenomenon generated in the slit gap 31 are weakened, which can effectively improve the "Gregorig" effect, thereby achieving the purpose of improving the heat exchange efficiency of the heat exchange tube.

[0067] The relationship between the width h4 of the slit gap 31 and the height h2 of the groove structure 3 is: 0.38 ≤ h4 / h2 ≤ 1. When the width of the slit gap 31 is larger, the more parts of the groove structure 3 are formed, the stronger the ability to pierce the liquid film, and the better the effect of using surface tension to accelerate the flow of refrigerant, resulting in faster downward flow of the liquid film. However, at this time, the parts of the structure are finer, and the reliability of the structure is lower, causing a decrease in the reliability of both the groove structure 3 and the heat exchange tube. Conversely, when the width of the slit gap 31 is smaller, the fewer parts of the groove structure 3 are formed, the weaker the ability to pierce the liquid film, the worse the flow effect of the liquid film, and the lower the heat exchange efficiency of the heat exchange tube. Only when 0.38 ≤ h4 / h2 ≤ 1 can the ability to pierce the liquid film be guaranteed while ensuring the structural reliability of the heat exchange tube, thus improving the heat exchange efficiency of the heat exchange tube.

[0068] Optionally, the width of the slit gap 31 ranges from 0.05 mm to 0.2 mm. In this embodiment, the number of outer fins 2 per inch along the axial direction of the heat exchange tube is 11 to 60. That is, the distance between two adjacent outer fins 2 along the axial direction of the heat exchange tube ranges from 0.42 mm to 2.3 mm, the height h2 of the groove structure 3 ranges from 0.05 mm to 0.65 mm, and the groove diameter d of the groove structure 3 ranges from 0.05 mm to 1.3 mm. In this case, the perimeter of the groove structure 3 ranges from 0.05 mm to 1.3 mm. If the width of the slit gap 31 exceeds 0.2 mm, the width of the portion formed by dividing the groove structure 3 will be too small. Taking a groove diameter d of 0.5 mm as an example, when the width of the slit gap 31 is 0.25 mm, the groove structure 3 is divided into two parts, each with a width of only 0.54 mm, which seriously affects the structural strength of the groove structure 3. If the width of the slit gap 31 is less than 0.05 mm, the slit gap 31 is too small to achieve the piercing effect on the liquid film, which will also reduce the heat exchange efficiency of the heat exchange tube. Only when the width of the slit gap 31 is between 0.05 mm and 0.2 mm can the ability to pierce the liquid film be guaranteed while ensuring the structural reliability of the heat exchange tube, thereby improving the heat exchange efficiency of the heat exchange tube.

[0069] The shape of the slit gap 31 can be triangular, trapezoidal, rectangular, etc.

[0070] Preferably, the number of slit gaps 31 is 2 to 8. The more slit gaps 31 there are, the smaller the width of the part divided by the groove structure 3, and the lower the structural strength. The fewer slit gaps 31 there are, the fewer sharp edges and sharp points used to pierce the liquid film, and the lower the piercing ability of the liquid film. Only when the number of slit gaps 31 is between 2 and 8 can the structural strength and the piercing ability of the liquid film be guaranteed, and the heat exchange efficiency of the heat exchange tube be improved.

[0071] like Figure 5 and Figure 6 As shown, the slit gap 31 can also be omitted, that is, the size of the slit gap 31 is 0mm. At this time, there are no gaps on the outer wall of the trough structure 3. The trough structure 3 can only use the edge of the trough opening to pierce the liquid film and use the shape of the trough structure 3 to generate vortices in the fluid. It cannot pierce the liquid film or guide the fluid at the side wall of the trough structure 3. However, the structural strength of the trough structure 3 reaches the maximum, which effectively improves the structural strength of the heat exchange tube.

[0072] like Figures 7 to 9As shown, the depth h3 of the slit gap 31 is equal to the side wall length of the trough structure 3. At this time, the slit gap 31 reaches its maximum value, and the trough structure 3 is completely divided into several independent parts. The sharp edges and sharp points formed by the trough structure 3 reach their maximum, and the ability to pierce the liquid film is stronger. This can maximize the heat exchange efficiency of the heat exchange tube. However, the independent parts have lower structural strength, which will affect the structural strength of the heat exchange tube.

[0073] like Figure 3 As shown, the sidewall of the groove structure 3 and the sidewall of the outer fin 2 have an included angle α, which ranges from 15° to 75°. Adjusting the included angle α can also adjust the extent of the groove structure 3 extending to both sides of the outer fin 2 and the height h2 of the groove structure 3, thus limiting the shape of the groove structure 3. If the included angle α is too small, it cannot form a large deformation at the top of the outer fin 2, resulting in a poor piercing effect of the groove structure 3 on the liquid film and a poor ability to generate eddies. It cannot utilize surface tension to accelerate the flow of refrigerant, thus failing to improve the heat exchange efficiency of the heat exchange tube. Conversely, if the included angle α is too large, the groove structure 3 forms a planar structure at the top of the outer fin 2, which not only fails to guide the fluid but also causes the distance between the tops of the outer fins 2 to be too small, increasing the "bridging" phenomenon and also affecting the heat exchange efficiency of the heat exchange tube. Only when the included angle α is within the range of 15° to 75° can the shape of the groove structure 3 be ensured to be within the range of the top of the outer fin 2. The shape adjustment effect maximizes the liquid phase pressure at the top of the fluid, increasing the pressure difference between the top and root of the outer fin 2, thus promoting refrigerant flow towards the root of the outer fin 2. Furthermore, the groove edge of the groove structure 3 can cleave the liquid film, resulting in uneven liquid film distribution and reducing average thermal resistance ("Gregorig effect"). This overcomes the problems of fluid stagnation and "bridging" on the surface of the outer fin 2 in existing technologies. Moreover, the shape of the groove structure 3 within this range can match the spiral arrangement of the outer fin 2. The fluid flowing spirally through the outer fin 2 generates local eddies within the groove structure 3, further enhancing the turning point of the fluid as it flows through the groove structure 3. Surface tension promotes faster refrigerant flow, reduces the thermal resistance of the heat exchange tube, increases the convective heat transfer coefficient and the degree of fluid turbulence, effectively improving the heat exchange efficiency of the heat exchange tube.

[0074] The height of the groove structure 3 is less than or equal to the depth of the mounting groove. In this case, the groove structure 3 will not affect the height of the outer fins 2, that is, it will not affect the maximum outer diameter of the heat exchange tube, thereby ensuring that the heat exchange tube can be used interchangeably with heat exchange tubes without the groove structure 3, avoiding the need for structural adaptation of the heat exchange tube in this application, and further reducing production costs.

[0075] The relationship between the height h2 of the groove structure 3 and the height h1 of the outer fin 2 is 0.03 ≤ h2 / h1 ≤ 0.43. When the height h2 of the groove structure 3 is too large, the protruding position of the groove structure 3 on the outer fin 2 is closer to the root of the outer fin 2, resulting in a smaller cross-sectional area of ​​the flow channel formed between the outer fins 2. This reduces the amount of fluid that can pass through the flow channel, which in turn affects the heat exchange efficiency of the heat exchange tube. Conversely, when the height h2 of the groove structure 3 is too small, the deformation effect of the groove structure 3 on the top of the outer fin 2 becomes worse. The groove structure 3 cannot reliably generate eddies in the fluid, and the piercing effect on the liquid film also becomes lower, which also affects the heat exchange efficiency of the heat exchange tube. Only when 0.03 ≤ h2 / h1 ≤ 0.43 can the deformation effect of the groove structure 3 on the top of the outer fin 2 and the piercing effect on the liquid film be guaranteed, effectively improving the heat exchange efficiency of the heat exchange tube.

[0076] Optionally, in this embodiment, the height h1 of the outer fin 2 ranges from 0.3mm to 1.5mm, and the height h2 of the groove structure 3 ranges from 0.05mm to 0.65mm. If the height h2 of the groove structure 3 is too large; for example, if the height h1 of the outer fin 2 is 1.3mm and the height h2 of the groove structure 3 is 0.7mm, then the groove structure 3 occupies more than half the height of the outer fin 2, and the height of the flow channel formed between adjacent outer fins 2 is only 0.6mm. Compared with the height of 1.3mm when the groove structure 3 is not provided, the cross-sectional area of ​​the flow channel is greatly reduced, and the amount of fluid that can flow through it will also be severely reduced. The fluid flowing through the flow channel can pass through the pipe. The heat exchanger 1 directly exchanges heat with the heat exchange medium inside the tube body 1. A reduction in the fluid volume will seriously affect the heat exchange efficiency. When the height of the trough structure 3 is too small, for example, if the height h of the outer fin 2 is 1.5 mm and the height h2 of the trough structure 3 is 0.04 mm, the height of the outer fin 2 occupied by the trough structure 3 is only 2.7%, which has little impact on the top shape of the outer fin 2. Liquid film and "bridging" problems can still occur between the outer fins 2. Only when the height h2 of the trough structure 3 is in the range of 0.05 mm to 0.65 mm can the deformation effect of the top of the outer fin 2 and the piercing effect of the liquid film by the trough structure 3 be guaranteed, thus effectively improving the heat exchange efficiency of the heat exchange tube.

[0077] In one embodiment, the heat exchange tube includes at least two auxiliary fins 32. The first end of each auxiliary fin 32 is located at the bottom surface of the mounting groove, and the second end extends away from the tube body 1. All the auxiliary fins 32 together form the groove structure 3. That is, by setting auxiliary fins 32 on the heat exchange tube, all auxiliary fins 32 are arranged in a ring around the center point of the bottom surface of the mounting groove, thereby forming the groove structure 3. When the groove structure 3 is formed by extruding the outer fins 2, a slit gap 31 can be set in the groove structure 3 during or after the extrusion process to form the auxiliary fins 32. Alternatively, the groove structure 3 can also be obtained by independently setting auxiliary fins 32 and welding them within the mounting groove.

[0078] The slot of the groove structure 3 has a slot gap 31 extending towards the top of the groove structure 3, and there is a gap between two adjacent auxiliary fins 32, the gap forming the slot gap 31.

[0079] The spacing ranges from 0 mm to 0.2 mm. When the spacing is 0 mm, adjacent auxiliary fins 32 are sealed together, and the groove structure 3 is a complete groove. The sidewalls of the groove structure 3 cannot pierce the liquid film, nor can fluid pass through. The groove structure 3 can only pierce the liquid film using the edge of the groove opening, and the shape of the groove structure 3 can generate eddies in the fluid. When the spacing is not 0 mm, the edges of the auxiliary fins 32 can pierce the liquid film, and this spacing can also allow fluid to pass through, thereby generating eddies in the fluid, increasing the turbulence of the fluid, and thus improving the heat exchange efficiency.

[0080] Preferably, there is a gap between two adjacent auxiliary fins 32, and the gap gradually increases along the direction from the first end to the second end of the auxiliary fin 32. That is, the shape of the gap (the shape of the slot gap 31) can form a triangle or a trapezoid. At the same time, when the groove structure 3 is formed by extruding the outer fins 2, the gradual increase in the gap can reduce the extension of the deformed part of the outer fin 2, thereby further ensuring the thickness and structural strength of the auxiliary fins 32, and thus improving the structural strength of the heat exchange tube.

[0081] The angle α between the line connecting the first and second ends of the auxiliary fin 32 and the sidewall of the outer fin 2 ranges from 15° to 75°. Figure 3As shown, the line connecting the first end and the second end of the auxiliary fin 32 is the profile of the auxiliary fin 32 on this cross section. Therefore, the angle formed between the connecting line and the sidewall and the angle between the sidewall of the groove structure 3 and the sidewall of the outer fin 2 are both α. Adjusting the included angle α can also adjust the extent of the expansion of the groove structure 3 to both sides of the outer fins 2 and the height h2 of the groove structure 3, thus limiting the shape of the groove structure 3. If the included angle α is too small, it cannot form a large deformation at the top of the outer fins 2, resulting in a poor piercing effect of the groove structure 3 on the liquid film and a poor ability to generate eddies. It cannot utilize surface tension to accelerate the flow of refrigerant, thus failing to improve the heat exchange efficiency of the heat exchange tube. Conversely, if the included angle α is too large, the groove structure 3 forms a planar structure at the top of the outer fins 2, which not only fails to guide the fluid but also causes the distance between the tops of the outer fins 2 to be too small, increasing the "bridging" phenomenon and also affecting the heat exchange efficiency of the heat exchange tube. Only when the included angle α is within the range of 15° to 75° can the shape of the groove structure 3 be guaranteed to be within the range of the top of the outer fins 2. The shape adjustment effect maximizes the liquid phase pressure at the top of the fluid, increasing the pressure difference between the top and root of the outer fin 2, thus promoting refrigerant flow towards the root of the outer fin 2. Furthermore, the groove edge of the groove structure 3 can cleave the liquid film, resulting in uneven liquid film distribution and reducing average thermal resistance ("Gregorig effect"). This overcomes the problems of fluid stagnation and "bridging" on the surface of the outer fin 2 in existing technologies. Moreover, the shape of the groove structure 3 within this range can match the spiral arrangement of the outer fin 2. The fluid flowing spirally through the outer fin 2 generates local eddies within the groove structure 3, further enhancing the turning point of the fluid as it flows through the groove structure 3. Surface tension promotes faster refrigerant flow, reduces the thermal resistance of the heat exchange tube, increases the convective heat transfer coefficient and the degree of fluid turbulence, effectively improving the heat exchange efficiency of the heat exchange tube.

[0082] There is a clearance between two adjacent trough structures 3, and the clearance ranges from 0.05 mm to 1.1 mm. By setting the clearance, interference between the two trough structures 3 can be avoided, which would cause "bridging" between the outer fins 2, thus ensuring the heat exchange efficiency of the heat exchange tube.

[0083] Specifically, along the length of the outer fin 2, the circumferential clearance s1 between two adjacent groove structures 3 ranges from 0.1 mm to 1.1 mm. This avoids structural interference between the groove structures 3, ensures the structural reliability of the outer fin 2, and thus guarantees the structural strength of the heat exchange tube.

[0084] Along the axial direction of the heat exchange tube, the axial clearance distance s2 between two adjacent groove structures 3 ranges from 0.05 mm to 1 mm. At this distance, the two groove structures 3 are positioned close together above the flow channel between the two outer fins 2. The two groove structures 3 simultaneously restrict the flow channel, enabling the top liquid phase pressure of the fluid to reach its maximum value as quickly as possible. This increases the pressure difference between the top and root of the outer fins 2, promoting refrigerant flow towards the root of the outer fins 2 and preventing refrigerant stagnation on the surface of the outer fins 2, thus improving heat exchange efficiency. If the axial clearance distance s2 is too large, it will not be able to increase the top liquid phase pressure of the fluid, affecting heat exchange efficiency. Conversely, if the axial clearance distance s2 is too small, the amount of refrigerant entering the flow channel will decrease, reducing heat exchange efficiency. Only when the axial clearance distance s2 is between 0.05 mm and 1 mm can the heat exchange efficiency of the heat exchange tube be guaranteed.

[0085] To further improve the heat exchange efficiency of the heat exchange tube, internal teeth 4 are provided on the inner wall of the heat exchange tube. The internal teeth 4 are used to turbulent the fluid flowing through the heat exchange tube, enhance the heat exchange efficiency between the inside and outside of the heat exchange tube, and thus improve the heat exchange efficiency of the heat exchange tube.

[0086] The inner teeth 4 are spirally arranged on the inner wall of the tube body 1. The cross-section of the inner teeth 4 is triangular or other shapes. The tooth tip angle of the inner teeth 4 ranges from 10° to 120°. The tooth tip angle of the inner teeth 4 is used to turbulent the fluid flowing in the heat exchange tube, forcing the fluid to adhere to the inner wall of the heat exchange tube to enhance the heat exchange efficiency.

[0087] The angle between the internal thread teeth 4 and the axis of the tube body 1 ranges from 0° to 75°, the number of internal threads 4 is 6 to 90, and the height of the internal threads 4 is 0.1 mm to 0.6 mm.

[0088] The outer fins 2 are spirally arranged on the outer wall of the tube body 1, and the spiral angle of the outer fins 2 ranges from 0.2° to 2.5°. By spirally arranging the outer fins 2, a spiral flow channel is formed on the outer wall of the tube body 1. While ensuring the spiral flow of the fluid, the spiral angle is used to limit the distance of the outer fins 2 on the axis, so that the axial clearance s2 of the groove structure 3 set at the top of the outer fins 2 is within the range of 0.05mm to 1mm, thereby improving the heat exchange efficiency of the heat exchange tube.

[0089] The following table compares and illustrates the heat exchange tubes (ordinary fins) in the prior art that do not have a groove structure with the heat exchange tubes (patented fins) in this application that have a groove structure 3:

[0090]

[0091] The prior art and the present application have the same four parameters for the internal teeth of the tube; the only difference is the fin shape on the outside of the tube. The single-tube heat transfer performance of the prior art and the present application was tested at a saturation temperature of 36°C and with refrigerant R134a. See [link to comparison]. Figure 10 and Figure 11 .

[0092] Figure 10 A performance comparison chart of the external heat transfer coefficient ho of existing technology and this application. From Figure 10 As can be seen from the data, with the increase of heat flux density q", the external performance ho of this application is about 8.7% to 23.1% higher than that of the prior art, with an average increase of 16.1%.

[0093] Figure 11 A performance comparison chart of the overall heat transfer coefficient Uo of existing technologies and this application. From Figure 11 As can be seen from the data, the overall heat transfer performance Uo of this application can increase with the increase of the flow velocity v in the pipe, which is about 5.1% higher than that of the prior art on average.

[0094] Specifically, the processing method for the heat exchange tube is as follows: First, outer fins 2 are machined on the tube body 1. Then, a special tool is used to press a groove-shaped structure 3 and an installation groove downwards on the top of the outer fins 2. The slot gap 31 of the groove-shaped structure 3 can be formed simultaneously during the pressing process with the special tool. The use of rolling and spinning techniques does not increase the manufacturing material of the tube body 1, which saves production costs and increases the strength and heat transfer area of ​​the tube body 1.

[0095] A heat exchanger comprising the heat exchange tubes described above.

[0096] An air conditioning device includes the aforementioned heat exchange tube or heat exchanger.

[0097] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A heat exchange tube, characterized by: include: tube body(1); The outer fin (2) is disposed on the outer wall of the tube body (1), and the outer fin (2) has a first edge away from the tube body (1), and the first edge is recessed in the direction of the tube body (1) to form an installation groove; The groove structure (3) is provided at the mounting groove, and the groove opening of the groove structure (3) faces away from the pipe body (1).

2. The heat exchange tube of claim 1, wherein: The maximum outer diameter of the groove structure (3) is greater than the thickness of the outer fin (2), and the groove structure (3) protrudes at least partially from the outer fin (2).

3. The heat exchange tube of claim 1, wherein: The groove structure (3) is shaped like a spherical cap or a bowl, with the top of the spherical cap or the top of the bowl abutting against the bottom surface of the mounting groove.

4. The heat exchange tube of claim 3, wherein: Along the direction away from the tube body (1), the cross-sectional dimensions of the groove structure (3) gradually increase.

5. The heat exchange tube of claim 3, wherein: The slot is circular in shape, and the relationship between the diameter d of the slot and the height h1 of the outer fin (2) is: 0.16≤d / h1≤0.87; or, the diameter d of the slot is in the range of 0.05mm to 1.3mm.

6. The heat exchange tube of claim 1, wherein: The groove structure (3) is provided with a slit gap (31), which extends from the groove of the groove structure (3) toward the pipe body (1).

7. The heat exchange tube of claim 6, wherein: The relationship between the depth h3 of the slot gap (31) and the height h2 of the groove structure (3) is: 0.03≤h3 / h2≤1; or, the depth h3 of the slot gap (31) ranges from 0.02mm to 0.65mm.

8. The heat exchange tube of claim 6, wherein: The relationship between the width h4 of the slit gap (31) and the height h2 of the groove structure (3) is: 0.38≤h4 / h2≤1; or, the width of the slit gap (31) is in the range of 0.05mm to 0.2mm.

9. The heat exchange tube of claim 1, wherein: The sidewall of the groove structure (3) and the sidewall of the outer fin (2) have an included angle α, the angle α being in the range of 15° to 75°.

10. The heat exchange tube of claim 1, wherein: The height of the groove structure (3) is less than or equal to the depth of the mounting groove.

11. The heat exchange tube of claim 1, wherein: The relationship between the height h2 of the groove structure (3) and the height h1 of the outer fin (2) is 0.03≤h2 / h1≤0.43; or, the height h2 of the groove structure (3) is in the range of 0.05mm to 0.65mm.

12. The heat exchange tube according to any one of claims 1 to 11, characterized in that: The heat exchange tube includes at least two auxiliary fins (32). The first end of the auxiliary fin (32) is located at the bottom surface of the mounting groove, and the second end extends away from the tube body (1). All the auxiliary fins (32) together form the groove structure (3).

13. The heat exchange tube of claim 12, wherein: The slot of the groove structure (3) has a slot gap (31) opening towards the top of the groove structure (3), and there is a gap between two adjacent auxiliary fins (32), the gap forming the slot gap (31).

14. The heat exchange tube of claim 13, wherein: The spacing ranges from 0 mm to 0.2 mm.

15. The heat exchange tube according to claim 13, characterized in that: There is a gap between two adjacent auxiliary fins (32), and the gap gradually increases along the direction from the first end to the second end of the auxiliary fin (32).

16. The heat exchange tube according to claim 12, characterized in that: The angle α between the line connecting the first and second ends of the auxiliary fin (32) and the sidewall of the outer fin (2) ranges from 15° to 75°.

17. The heat exchange tube according to claim 1, characterized in that: There is a clearance between two adjacent groove structures (3), and the clearance ranges from 0.05 mm to 1.1 mm.

18. The heat exchange tube according to claim 17, characterized in that: Along the length direction of the outer fin (2), the circumferential clearance s1 between two adjacent groove structures (3) ranges from 0.1 mm to 1.1 mm; and / or, along the axial direction of the heat exchange tube, the axial clearance s2 between two adjacent groove structures (3) ranges from 0.05 mm to 1 mm.

19. The heat exchange tube according to claim 1, characterized in that: The heat exchange tube has internal teeth (4) on its inner wall.

20. The heat exchange tube according to claim 1, characterized in that: The outer fins (2) are arranged in a spiral shape on the outer wall of the tube (1), and the spiral angle of the outer fins (2) ranges from 0.2° to 2.5°.

21. A heat exchanger, characterized in that: It includes the heat exchange tube according to any one of claims 1 to 20.

22. An air conditioning device, characterized in that: It includes the heat exchange tube according to any one of claims 1 to 20 or the heat exchanger according to claim 21.

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