Fin and tube heat exchanger

Abstract

The application relates to the technical field of heat exchange, in particular to a heat exchange fin and tube fin heat exchanger which can be used for heat exchange with fluid outside a tube, wherein the heat exchange fin is provided with a plurality of heat exchange tube holes, and the heat exchange fin is connected to a heat exchange tube bundle through the heat exchange tube holes; the heat exchange fin is provided with a first arc-shaped structure and a second arc-shaped structure which are formed by concave and / or convex surfaces of the heat exchange fin, and the circle where the first arc-shaped structure and the second arc-shaped structure are located and the circular section of the heat exchange tube hole are concentric circles; along the width direction of the heat exchange fin, the first arc-shaped structure and the second arc-shaped structure are distributed on both sides of the heat exchange tube hole; along the length direction of the heat exchange fin, the first arc-shaped structure and the second arc-shaped structure are symmetrically arranged along the flow direction of the fluid outside the tube, an air inlet flow channel is formed between adjacent first arc-shaped structures, and an air outlet flow channel is formed between adjacent second arc-shaped structures. The heat exchange fin provided by the application arranges the first arc-shaped structure and the second arc-shaped structure around the heat exchange tube hole, guides the flow to deviate from the heat exchange tube, reduces the area of a wake zone, and improves the heat exchange effect.

Description

[Technical Field]

[0001] This application relates to the field of heat exchange technology, and in particular to a heat exchange finned and tube-finned heat exchanger. [Background Technology]

[0002] A tube-fin heat exchanger is a highly efficient heat exchange device that improves heat transfer efficiency by increasing the heat exchange area. It mainly consists of heat exchange tube bundles and heat exchange fins. The temperature of the fluid inside the tube bundle is transferred to the heat exchange fins, and the heat is then transferred away by the heat exchange fins through heat exchange with the fluid outside the tubes. The specific structure of a tube-fin heat exchanger is as follows: multiple heat exchange fins are stacked, and the fins have staggered heat exchange tube holes that run through the stacking direction. The heat exchange tubes connect the heat exchange fins through these tube holes.

[0003] In the process of developing this application, the inventors discovered at least the following technical problems in the prior art:

[0004] In the tube-fin heat exchanger with the above structure, when the fluid outside the tube flows perpendicular to the axis of the heat exchange tube, some of the fluid bypasses the heat exchange tube and forms a flow around the heat exchange tube. As the heat exchange process proceeds, when the fluid outside the tube bypasses the heat exchange tube, the fluid behind the tube separates. The fluid velocity near the tube wall gradually decreases, the fluid momentum decreases, and it becomes increasingly difficult to overcome the rising pressure, thus forming a wake region. The low-velocity fluid region of the wake region leads to a decrease in the heat exchange efficiency between the fluid and the heat exchange tube, thereby reducing the heat exchange performance of the heat exchanger. [Summary of the Invention]

[0005] In view of this, this application provides a heat exchange fin and tube-fin heat exchanger, which can reduce the area of ​​the wake region and improve the heat exchange effect of the heat exchange fins.

[0006] In a first aspect, this application provides a heat exchange fin, which is provided with a plurality of heat exchange tube holes, and the heat exchange fin can be used to connect to a heat exchange tube bundle through the heat exchange tube holes;

[0007] The heat exchange fins are further provided with a first arc-shaped structure and a second arc-shaped structure. Along the thickness direction of the heat exchange fins, the first arc-shaped structure and the second arc-shaped structure are formed by recesses and / or protrusions from the surface of the heat exchange fins, and the circles containing the first arc-shaped structure and / or the second arc-shaped structure are concentric circles with the circular cross-section of the heat exchange tube hole.

[0008] Along the width direction of the heat exchange fins, the first arc-shaped structure and the second arc-shaped structure are distributed on both sides of the heat exchange tube hole; along the length direction of the heat exchange fins, the first arc-shaped structure and the second arc-shaped structure are symmetrically arranged along the flow direction of the fluid outside the tube, and an air inlet channel is formed between adjacent first arc-shaped structures, and an air outlet channel is formed between adjacent second arc-shaped structures.

[0009] In some embodiments, the central angle of the first arc structure is α1, and the angle between the first end of the first arc structure and the flow direction of the fluid outside the pipe is β1, wherein the central angle α1 and the angle β1 satisfy: 10°<α1+β1<90°.

[0010] The central angle of the second arc-shaped structure is α2, and the angle between the tail end of the second arc-shaped structure and the flow direction of the fluid outside the pipe is β2. The central angle α2 and the angle β2 satisfy: 10°<α2+β2<90°.

[0011] In some embodiments, the spacing between adjacent heat exchange fins is Fp, and the heights of the first arc-shaped structure and the second arc-shaped structure are H;

[0012] The relationship between the spacing Fp between adjacent heat exchange fins and the height H of the first arc-shaped structure and the second arc-shaped structure satisfies: 0.2Fp < H < 0.9Fp.

[0013] In some embodiments, the widths of the first arc-shaped structure and the second arc-shaped structure are L;

[0014] The relationship between the width L and height H of the first arc-shaped structure and the second arc-shaped structure satisfies: H < L < 2H.

[0015] In some embodiments, the diameter of the heat exchange tube hole is d, the spacing between the rows of the heat exchange tube holes along the width direction of the heat exchange fins is P, and the radius of the circle containing the first arc-shaped structure and the second arc-shaped structure is R.

[0016] The relationship between the radius R of the circles containing the first and second arc-shaped structures, the diameter d of the heat exchange tube holes, and the spacing P of the heat exchange tube holes satisfies: d <R+L<P。

[0017] In some embodiments, the surfaces of the first arc-shaped structure and the second arc-shaped structure are arc surfaces, and the beginning and end ends of the first arc-shaped structure and the second arc-shaped structure are provided with rounded corners.

[0018] In some implementations, the concentric circles containing the first arc-shaped structure and the second arc-shaped structure do not coincide.

[0019] In some embodiments, the first arc-shaped structure and the second arc-shaped structure protrude only on one side of the heat exchange fins.

[0020] In some embodiments, the heat exchange tube holes in adjacent rows of heat exchange tube holes are staggered along the width direction of the heat exchange fins.

[0021] Secondly, this application provides a tube-fin heat exchanger, the tube-fin heat exchanger comprising a heat exchange tube bundle and heat exchange fins as described in any one of the first aspects.

[0022] By adopting the above technical solution, this application has at least the following beneficial effects:

[0023] The heat exchange fins provided in this application have surface depressions and / or protrusions forming a first arc-shaped structure and a second arc-shaped structure. The first and second arc-shaped structures are arranged around the heat exchange tube orifice, and the circles containing the first and second arc-shaped structures are concentric circles with the heat exchange tube orifice. First, when the fluid outside the tube flows through the first and second arc-shaped structures, it interacts with them, generating a velocity component perpendicular to the flow direction of the fluid outside the tube. This perpendicular velocity component shears the boundary layer, thereby disrupting and thinning the boundary layer, and improving the heat exchange efficiency between the fluid outside the tube and the surface of the heat exchange fins. Second, when the fluid outside the tube flows from the inlet channel to the heat exchange tube, the first and second arc-shaped structures guide the fluid outside the tube to flow backward. The cooperation between the second arc-shaped structure and the heat exchange tube reduces the flow cross-section of the fluid outside the tube and increases the flow velocity, causing the fluid outside the tube to eventually flow towards the heat exchange tube, thereby reducing the wake area on the leeward side of the heat exchange tube and improving the heat exchange performance of the heat exchange fins. [Attached Image Description]

[0024] Figure 1 A partial structural schematic diagram of the heat exchange fins provided in this application;

[0025] Figure 2 A cross-sectional view of the heat exchange fins provided in this application;

[0026] Figure 3 A schematic diagram of the arc-shaped structure of the heat exchange fins provided in this application;

[0027] Figure 4 A cross-section of an arc-shaped structure of the heat exchange fins provided in this application;

[0028] Figure 5 The cross-section of another arc-shaped structure of the heat exchange fins provided in this application;

[0029] Figure 6 This is another arc-shaped structure of the heat exchange fins provided in this application;

[0030] Figure 7 A comparison diagram of the Nusselt number Nu of Example 1 and Comparative Examples 1-2 provided in this application.

[0031] Attached image labels:

[0032] 1. Heat exchange tube holes; 2. First arc-shaped structure; 3. Second arc-shaped structure.

Detailed Implementation Methods

[0033] To better understand the technical solution of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0034] It should be understood that the described embodiments are merely some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0035] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0036] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0037] It should be noted that the directional terms such as "upper," "lower," "left," and "right" described in the embodiments of this application are used to describe the angles shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should be understood that when it is mentioned that an element is connected "upper" or "lower" to another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected to the other element "upper" or "lower" through an intermediate element.

[0038] A tube-fin heat exchanger is a highly efficient heat exchange device that improves heat transfer efficiency by increasing the heat exchange area. It mainly consists of heat exchange tube bundles and heat exchange fins. The temperature of the fluid inside the tube bundle is transferred to the heat exchange fins, and the heat is then transferred away by the heat exchange fins through heat exchange with the fluid outside the tubes. The specific structure of a tube-fin heat exchanger is as follows: multiple heat exchange fins are stacked, and the fins have staggered heat exchange tube holes that run through the stacking direction. The heat exchange tubes connect the heat exchange fins through these tube holes.

[0039] In the tube-fin heat exchanger with the above structure, when the fluid outside the tube flows perpendicular to the axis of the heat exchange tube, some of the fluid bypasses the heat exchange tube and forms a flow around the heat exchange tube. As the heat exchange process proceeds, when the fluid outside the tube bypasses the heat exchange tube, the fluid behind the tube separates. The fluid velocity near the tube wall gradually decreases, the fluid momentum decreases, and it becomes increasingly difficult to overcome the rising pressure, thus forming a wake region. The low-velocity fluid region of the wake region leads to a decrease in the heat exchange efficiency between the fluid and the heat exchange tube, thereby reducing the heat exchange performance of the heat exchanger.

[0040] In view of this, this application provides a heat exchange fin that can be configured with a heat exchange tube bundle to form a tube-fin heat exchanger. The heat exchange fin can be used for heat exchange with the fluid outside the tubes (the fluid outside the heat exchange tube bundle, usually air). Please refer to [reference needed]. Figures 1-6 The heat exchange fins are provided with multiple heat exchange tube holes 1, and the heat exchange fins can be used to connect to the heat exchange tube bundle through the heat exchange tube holes 1.

[0041] The heat exchange fins are also provided with a first arc-shaped structure 2 and a second arc-shaped structure 3. Along the thickness direction of the heat exchange fins, the first arc-shaped structure 2 and the second arc-shaped structure 3 are formed by recesses and / or protrusions from the surface of the heat exchange fins, and the circles containing the first arc-shaped structure 2 and / or the second arc-shaped structure 3 are concentric circles with the circular cross-section of the heat exchange tube hole 1.

[0042] Along the width direction of the heat exchange fins, the first arc-shaped structure 2 and the second arc-shaped structure 3 are distributed on both sides of the heat exchange tube hole 1; along the length direction of the heat exchange fins, the first arc-shaped structure 2 and the second arc-shaped structure 3 are symmetrically arranged along the flow direction of the fluid outside the tube, and an air inlet channel is formed between adjacent first arc-shaped structures 2, and an air outlet channel is formed between adjacent second arc-shaped structures 3.

[0043] In the above solution, the heat exchange fins provided in this application have surface depressions and / or protrusions forming a first arc-shaped structure 2 and a second arc-shaped structure 3. The first arc-shaped structure 2 and the second arc-shaped structure 3 are arranged around the heat exchange tube hole 1, and the circles containing the first arc-shaped structure 2 and the second arc-shaped structure 3 are concentric circles with the heat exchange tube hole 1. Firstly, when the fluid outside the tube flows through the first arc-shaped structure 2 and the second arc-shaped structure 3, it will interact with them, generating a velocity component perpendicular to the flow direction of the fluid outside the tube. It shears the boundary layer, thereby breaking down and thinning it, and improving the heat exchange efficiency between the fluid outside the tube and the surface of the heat exchange fins. Secondly, when the fluid outside the tube flows from the inlet channel to the heat exchange tube, the first arc structure 2 and the second arc structure 3 guide the fluid outside the tube to flow backward. The cooperation between the second arc structure 3 and the heat exchange tube reduces the flow cross section of the fluid outside the tube and increases the flow velocity, causing the fluid outside the tube to eventually flow towards the heat exchange tube. This reduces the wake area on the leeward side of the heat exchange tube and improves the heat exchange performance of the heat exchange fins.

[0044] In some embodiments, the tube-fin heat exchanger includes a heat exchange tube bundle and a plurality of heat exchange fins. Further, the plurality of heat exchange fins are stacked.

[0045] The heat exchange tube bundle consists of multiple slender tubes made of materials with good thermal conductivity; for example, copper or aluminum can be used, and the material can be selected according to actual needs, without limitation. The heat exchange tube bundle contains a fluid that absorbs heat from the object to be cooled. After absorbing heat, the fluid transfers the heat to the outside of the heat exchange tube bundle through the tube walls.

[0046] The heat exchange fins are connected to the heat exchange tube bundle. Since the heat exchange rate is proportional to the surface area, the heat exchange area of ​​the tube-fin heat exchanger can be increased by setting the heat exchange fins, thereby improving the heat exchange efficiency. Moreover, the material of the heat exchange fins also has good thermal conductivity. For example, it can be copper or aluminum. The material of the heat exchange fins can be selected according to actual needs, and there is no limitation here.

[0047] The heat exchange fins and heat exchange tube bundle are connected through multiple heat exchange tube holes 1. Specifically, the heat exchange tube holes 1 are distributed in a dotted pattern on the heat exchange fins, and the heat exchange tube holes 1 in adjacent rows are staggered along the width direction of the heat exchange fins. This staggered arrangement (e.g., staggered layout) allows the external fluid to more evenly cover each heat exchange tube during flow, reducing obstruction of the preceding heat exchange tube by the following heat exchange tube and improving the heat exchange effect. When the heat exchange fins are fitted onto the heat exchange tube bundle through the heat exchange tube holes 1, they can be fixed by mechanical connections such as welding or interference fits, or by bonding with thermally conductive adhesive, to ensure a stable connection between the heat exchange fins and the heat exchange tube bundle. The connection method can be selected according to actual needs and is not limited here.

[0048] The heat exchange tube hole 1 used in this application has a shape of at least one of circular, elliptical, or regular polygonal. The shape of the heat exchange tube hole 1 can be selected according to actual needs and is not limited here. Preferably, the heat exchange tube hole 1 is circular with a diameter of d. The specific value of d can be selected according to the volume of the heat exchange fins. Adjacent heat exchange tube holes 1 are equally spaced. Along the width direction of the heat exchange fins, the row spacing of the heat exchange tube holes 1 is P. The size of P can be adjusted according to the volume of the tube-fin heat exchanger and is not limited here.

[0049] Optionally, the heat exchange fins on the heat exchange tube bundle can be arranged radially or in equal-spaced stacked configurations. Preferably, the heat exchange fins in this application are arranged in equal-spaced stacked configurations, with the spacing between adjacent heat exchange fins being Fp. The size of Fp can be adjusted according to the volume of the tube-fin heat exchanger. The heat exchange fins can increase the heat exchange area of ​​the tube-fin heat exchanger and improve heat exchange efficiency. In actual use, the heat transferred by the fluid inside the tubes through the tube walls of the heat exchange tube bundle is transferred to the heat exchange fins, at which point the heat exchange fins exchange heat with the fluid outside the tubes.

[0050] In some embodiments, along the thickness direction of the heat exchange fins, the surface of the heat exchange fins is recessed and / or protruded to form a first arc-shaped structure 2 and a second arc-shaped structure 3. For example, the first arc-shaped structure 2 and the second arc-shaped structure 3 can be formed by the back side of the heat exchange fins being recessed towards the front side, or by the front side of the heat exchange fins being recessed towards the back side, or by a portion of the heat exchange fins being recessed towards the front side, or by the front side of the heat exchange fins being recessed towards the back side to form a second first arc-shaped structure 2 and a second arc-shaped structure 3. The protrusion direction of the first arc-shaped structure 2 and the second arc-shaped structure 3 can be selected according to actual needs and is not limited here. Preferably, in the heat exchange fins of this application, the first arc-shaped structure 2 and the second arc-shaped structure 3 are formed by the back side of the heat exchange fins being recessed towards the front side, that is, they are only protruded on one side of the heat exchange fins.

[0051] Along the width direction of the heat exchange fins, the first arc-shaped structure 2 and the second arc-shaped structure 3 are distributed on both sides of the heat exchange tube hole 1. That is, the first arc-shaped structure 2 is used to guide the fluid outside the tube to flow to the heat exchange tube, and the second arc-shaped structure 3 is used to guide the fluid outside the tube at the front of the heat exchange tube to flow to the rear of the heat exchange tube.

[0052] Along the length of the heat exchange fins, the first arc-shaped structure 2 and the second arc-shaped structure 3 are symmetrically arranged along the flow direction of the fluid outside the tube. That is, in this application, each heat exchange tube is surrounded by two first arc-shaped structures 2 and two second arc-shaped structures 3. An inlet air channel is formed between adjacent first arc-shaped structures 2, and an outlet air channel is formed between adjacent second arc-shaped structures 3. It can be understood that when the fluid outside the tube flows from the inlet air channel to the heat exchange tube, the first arc-shaped structure 2 and the second arc-shaped structure 3 guide the fluid outside the tube to flow backward. The cooperation between the second arc-shaped structure 3 and the heat exchange tube reduces the flow cross-section of the fluid outside the tube and increases the flow velocity, causing the fluid outside the tube to eventually flow towards the heat exchange tube. This reduces the wake area on the leeward side of the heat exchange tube, improves the heat exchange performance of the heat exchange fins, and the fluid outside the tube that has completed heat exchange flows out from the outlet air channel.

[0053] The concentric circles containing the first arc-shaped structure 2 and the second arc-shaped structure 3 can be the same or different. For example, the radius of the concentric circle containing the first arc-shaped structure 2 can be larger than the radius of the concentric circle containing the second arc-shaped structure 3, or the radius of the concentric circle containing the second arc-shaped structure 3 can be larger than the radius of the concentric circle containing the first arc-shaped structure 2. Alternatively, the concentric circles containing the first arc-shaped structure 2 and the second arc-shaped structure 3 can coincide. The choice can be made according to actual needs and is not limited here. Preferably, the concentric circles containing the first arc-shaped structure 2 and the second arc-shaped structure 3 do not coincide, and the radius of the concentric circle containing the second arc-shaped structure 3 is larger than the radius of the concentric circle containing the first arc-shaped structure 2.

[0054] The central angle of the first arc-shaped structure 2 is α1, and the angle between the first end of the first arc-shaped structure 2 and the flow direction of the fluid outside the pipe is β1. The central angle α1 and the included angle β1 satisfy: 10° < α1 + β1 < 90°. Optionally, the sum of the central angle α1 and the included angle β1 can be 11°, 20°, 30°, 40°, 50°, 60°, 70°, 80°, and 89°, or other values ​​within this range, without limitation. It can be understood that the central angle α1 represents the arc length of the first arc-shaped structure 2, and the included angle β1 represents the width of the air intake channel. Furthermore, α1 + β1 represents the spatial position of the first arc-shaped structure 2. When the value of α1 + β1 is within the aforementioned range, adjacent first arc-shaped structures 2 can form an air intake channel, and the length of the first arc-shaped structure 2 is moderate, simultaneously serving to shear the boundary layer and guide the flow of the fluid outside the pipe.

[0055] The central angle of the second arc-shaped structure 3 is α2, and the angle between the first end of the second arc-shaped structure 3 and the flow direction of the fluid outside the pipe is β2. The central angle α2 and the included angle β2 satisfy: 10° < α2 + β2 < 90°. Optionally, the sum of the central angle α2 and the included angle β2 can be 11°, 20°, 30°, 40°, 50°, 60°, 70°, 80°, and 89°, or other values ​​within this range, without limitation. It can be understood that the central angle α2 represents the arc length of the second arc-shaped structure 3, and the included angle β2 represents the width of the airflow channel. Furthermore, α2 + β2 represents the spatial position of the second arc-shaped structure 3. When the value of α2 + β2 is within the aforementioned range, adjacent second arc-shaped structures 3 can form an airflow channel, and the length of the second arc-shaped structure 3 is moderate, simultaneously serving to shear the boundary layer and guide the flow of the fluid outside the pipe.

[0056] The surfaces of the first arc-shaped structure 2 and the second arc-shaped structure 3 are curved, and the beginning and end of the first arc-shaped structure 2 and the second arc-shaped structure 3 are rounded. It is understood that the curved surfaces and rounded corners on the first arc-shaped structure 2 and the second arc-shaped structure 3 can reduce the flow resistance to the fluid outside the pipe. Preferably, the cross-section of the first arc-shaped structure 2 and the second arc-shaped structure 3 of this application can be a combination of a rounded trapezoid and a rounded triangle, or a semicircle, or a combination of a semicircle and a rounded rectangle; the choice can be made according to actual needs and is not limited here.

[0057] The height of the first arc-shaped structure 2 and the second arc-shaped structure 3 is H. The relationship between the spacing Fp of adjacent heat exchange fins and the height H of the first arc-shaped structure 2 and the second arc-shaped structure 3 satisfies: 0.2Fp < H < 0.9Fp. Optionally, the relationship between the spacing Fp of adjacent heat exchange fins and the height H of the first arc-shaped structure 2 and the second arc-shaped structure 3 can be 0.21Fp, 0.31Fp, 0.41Fp, 0.51Fp, 0.61Fp, 0.71Fp, 0.81Fp, and 0.89Fp, or other values ​​within the range, which are not limited here. Understandably, the relationship between the spacing Fp between adjacent heat exchange fins and the height H of the first arc-shaped structure 2 and the second arc-shaped structure 3 is within the aforementioned range. The obstruction of the first arc-shaped structure 2 and the second arc-shaped structure 3 allows the fluid outside the pipe to generate a velocity component perpendicular to the flow direction, thereby shearing the boundary layer. At the same time, the protruding first arc-shaped structure 2 and the second arc-shaped structure 3 do not occupy a large space, ensuring that there is still a certain amount of space between adjacent heat exchange fins, guaranteeing the flow space of the fluid outside the pipe, and reducing flow resistance.

[0058] The widths of the first arc-shaped structure 2 and the second arc-shaped structure 3 are L, wherein the relationship between the width L and the height H of the first arc-shaped structure 2 and the second arc-shaped structure 3 satisfies: H < L < 2H. Optionally, the width of the second arc-shaped structure 3 can be 1.1H, 1.2H, 1.4H, 1.6H, 1.8H, and 1.9H, or other values ​​within this range, which are not limited here. It is understood that having the relationship between the width L and the height H of the first arc-shaped structure 2 and the second arc-shaped structure 3 within the above range can enhance the boundary layer reduction effect of the first arc-shaped structure 2 and the second arc-shaped structure 3 while reducing the volume of the first arc-shaped structure 2 and the second arc-shaped structure 3, so that there is still a certain space between adjacent heat exchange fins, ensuring the flow space of the fluid outside the pipe and reducing flow resistance.

[0059] The radius of the circles where the first arc-shaped structure 2 and the second arc-shaped structure 3 are located is R. Among them, the relationship between the radius R of the circles where the first arc-shaped structure 2 and the second arc-shaped structure 3 are located, the diameter d of the heat exchange tube holes 1, and the row spacing P of the heat exchange tube holes 1 satisfies: d < R + L < P. It can be understood that the radius R of the circles where the first arc-shaped structure 2 and the second arc-shaped structure 3 are located can be characterized by the central angle α and the included angle β for the arc lengths of the first arc-shaped structure 2 and the second arc-shaped structure 3. When the radius R of the circle is relatively small, the range of the flow cross-section is small, and the flow of the fluid outside the tube near the convex structure will be subject to a stronger guiding effect; when the radius R of the circle is relatively large, the range of the flow cross-section is large, and the flow of the fluid near the convex structure will be subject to a weaker guiding effect. When the radius R of the circles where the first arc-shaped structure 2 and the second arc-shaped structure 3 are located and the width are within the above range, the flow path of the fluid outside the tube can be optimized, the drainage effect can be enhanced, and the heat exchange efficiency of the finned tube heat exchanger can be improved.

[0060] It should be noted that when the concentric circles where the first arc-shaped structure 2 and the second arc-shaped structure 3 are located do not coincide, the radius of the circle where the first arc-shaped structure 2 is located is R1, the radius of the circle where the second arc-shaped structure 3 is located is R2, and both R1 and R2 satisfy d < R + L < P.

[0061] In the actual application process, different heat exchange effects and pressure drop values under different heat exchange conditions can be obtained by changing the specifications, placement positions, etc. of the first arc-shaped structure 2 and the second arc-shaped structure 3, and the manufacturing cost is not increased.

[0062] The technical solutions of the present application are described below in conjunction with specific embodiments:

[0063] Embodiment 1 [[ID=!4]]

[0064] The first arc-shaped structure and the second arc-shaped structure of the present application are arranged on the heat exchange fins. Among them, the width L1 of the first arc-shaped structure is 2 mm, the height H1 is 1.1 mm, the central angle α1 is 60°, β1 is 2°, and the radius R1 of the circle where it is located is 11 mm; the width L2 of the second arc-shaped structure is 2 mm, the height H2 is 1.5 mm, the central angle α2 is 30°, β2 is 42°, and the radius R2 of the circle where it is located is 9 mm.

[0065] Comparative Example 1

[0066] Different from Embodiment 1, no arc-shaped structure is provided on the heat exchange fins, and the heat exchange fins are flat fins.

[0067] Comparative Example 2

[0068] Different from Embodiment 1, no arc-shaped structure is provided on the heat exchange fins, and the heat exchange fins are corrugated fins.

[0069] The heat exchange fins and heat exchange tube bundles of Example 1 and Comparative Examples 1-2 were respectively assembled into a first tube-fin heat exchanger, a second tube-fin heat exchanger, and a third tube-fin heat exchanger.

[0070] test:

[0071] The heat exchange performance of the first, second, and third tube-fin heat exchangers was tested under the same air volume.

[0072] Test results:

[0073] Table 1

[0074]

[0075] Test Result Analysis:

[0076] First, the test results in the table show that the surface depressions and / or protrusions of the heat exchange fins form a first arc-shaped structure and a second arc-shaped structure. These structures are arranged around the heat exchange tube holes, and the circles containing them are concentric with the heat exchange tube holes. Compared to flat and corrugated structures, the Nusselt number Nu, heat transfer capacity Q, and heat transfer factor j of Example 1 are all increased, indicating enhanced heat exchange performance of the heat exchange fins. Simultaneously, based on the resistance coefficient f and j / f of Example 1… ^1 / 3 The numerical values ​​show that although the first and second arc-shaped structures increase the flow resistance of the fluid outside the pipe, they also reduce the area of ​​the wake region due to their guiding effect, thereby enhancing the heat exchange performance of the heat exchange fins.

[0077] Figure 7 For a comparison chart of the Nusselt number Nu of Embodiment 1 and Comparative Examples 1-2 provided in this application, please refer to... Figure 6 Based on the parameter settings for the arc-shaped flow guide, under the structure of the present invention, the heat exchange fins of the present invention have a 32.08% higher Nusselt number (Nu) compared to flat fins at the same Reynolds number, which significantly improves the heat exchange capacity.

[0078] This application also provides a tube-fin heat exchanger, which includes a heat exchange tube bundle and heat exchange fins of any of the above embodiments. Since the tube-fin heat exchanger uses the heat exchange fins of any of the above embodiments, it has the same technical effects as the heat exchange fins of any of the above embodiments, and will not be described again here.

[0079] The above description, based on the embodiments shown in the figures, details the structure, features, and effects of the present invention. The above description is only a preferred embodiment of the present invention, but the present invention is not limited to the scope of implementation shown in the figures. Any changes made in accordance with the concept of the present invention, or equivalent embodiments modified to have equivalent changes, that do not exceed the spirit covered by the specification and figures, should be within the protection scope of the present invention.

Claims

1. A heat exchange fin, characterized by, The heat exchange fin is provided with a plurality of heat exchange tube holes, and the heat exchange fin can be connected to a heat exchange tube bundle through the heat exchange tube holes; The heat exchange fin is further provided with a first arc-shaped structure and a second arc-shaped structure, which are recessed and / or protruded from the surface of the heat exchange fin along the thickness direction of the heat exchange fin, and the circle where the first arc-shaped structure and / or the second arc-shaped structure is located is concentric with the circular cross section of the heat exchange tube hole; Along the width direction of the heat exchange fin, the first arc-shaped structure and the second arc-shaped structure are distributed on both sides of the heat exchange tube hole; along the length direction of the heat exchange fin, the first arc-shaped structure and the second arc-shaped structure are symmetrically arranged along the flow direction of the fluid outside the tube, and the adjacent first arc-shaped structures form an inlet flow channel, and the adjacent second arc-shaped structures form an outlet flow channel; The central angle of the circle where the first arc-shaped structure is located is α1, the central angle of the circle where the second arc-shaped structure is located is α2, and α2<α1; the radius of the circle where the first arc-shaped structure is located is R1, and the radius of the circle where the second arc-shaped structure is located is R2, and R2<R1.

2. The heat exchange fin according to claim 1, wherein The central angle of the circle where the first arc-shaped structure is located is α1, and the included angle between the leading end of the first arc-shaped structure and the flow direction of the fluid outside the tube is β1, wherein the central angle α1 and the included angle β1 satisfy: 10°<α1+β1<90°; The central angle of the circle where the second arc-shaped structure is located is α2, and the included angle between the trailing end of the second arc-shaped structure and the flow direction of the fluid outside the tube is β2, wherein the central angle α2 and the included angle β2 satisfy: 10°<α2+β2<90°.

3. The heat exchange fin according to claim 2, wherein The fin spacing of adjacent heat exchange fins is Fp, and the height of the first arc-shaped structure and the second arc-shaped structure is H; Wherein, the relationship between the fin spacing Fp of adjacent heat exchange fins and the height H of the first arc-shaped structure and the second arc-shaped structure satisfies: 0.2Fp<H<0.9Fp.

4. The heat exchange fin according to claim 3, wherein The width of the first arc-shaped structure and the second arc-shaped structure is L; Wherein, the relationship between the width L and the height H of the first arc-shaped structure and the second arc-shaped structure satisfies: H<L<2H.

5. The heat exchange fin according to claim 4, wherein The tube diameter of the heat exchange tube hole is d, the row spacing of the heat exchange tube hole along the width direction of the heat exchange fin is P, and the radius of the circle where the first arc-shaped structure and the second arc-shaped structure are located is R; Wherein, the relationship between the radius R of the circle where the first arc-shaped structure and the second arc-shaped structure are located, the tube diameter d of the heat exchange tube hole, and the row spacing P of the heat exchange tube hole satisfies: d<R+L<P.

6. The heat exchange fin according to any one of claims 1 to 5, wherein The surface of the first arc-shaped structure and the second arc-shaped structure is arc surface, and the leading end and the trailing end of the first arc-shaped structure and the second arc-shaped structure are provided with a round corner.

7. The heat transfer fin according to any one of claims 1 to 5, wherein The concentric circles where the first arc-shaped structure and the second arc-shaped structure are located are not coincident.

8. The heat exchange fin according to any one of claims 1 to 5, wherein The first arc-shaped structure and the second arc-shaped structure are only protruded on one side of the heat exchange fin.

9. The heat exchange fin according to any one of claims 1 to 5, wherein Along the width direction of the heat exchange fin, the heat exchange tube holes in each adjacent row of heat exchange tube holes are distributed in a staggered manner.

10. A tube-fin heat exchanger, characterized by comprising: The tube fin heat exchanger comprises a heat exchange tube bundle and the heat exchange fin according to any one of claims 1-9.

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