Fin structure and heat exchanger

Abstract

The invention relates to the technical field of heat exchangers, and discloses a fin structure and a heat exchanger, the fin structure comprises fin units distributed in a plurality of columns, any fin unit comprises a bottom plate and a guide shell formed on the upper side of the bottom plate, and the interior of the guide shell is hollow; the guide shell is provided with a plurality of first openings formed in the first direction, a plurality of second openings formed in the direction opposite to the first direction, a plurality of third openings formed in the second direction and a plurality of fourth openings formed in the direction opposite to the second direction, and the four openings communicate with the interior of the guide shell. The straight line of the first direction intersects with the straight line of the second direction. Liquid can enter the fin units from any direction, namely, the fin can be selected as an inlet and an outlet from any direction, the fin can normally flow no matter which angle is selected, flowing dead zones in the heat exchanger can be reduced, the effective heat exchange area and the heat exchange efficiency are improved, and the plate-fin heat exchanger is more convenient to design.

Description

Technical Field

[0001] The present invention relates to the technical field of heat exchangers, and particularly relates to a fin structure and a heat exchanger. Background Art

[0002] In the field of heat exchange equipment, plate-fin heat exchangers have been widely used due to their high heat transfer performance and compact structural design. A plate-fin heat exchanger generally consists of side plates, partition plates, fins, and seals. The sandwich formed by placing fins, flow guiding sheets, and seals between two adjacent partition plates is called a channel. Stacking these channels according to different fluid flow patterns and welding them into a whole forms a plate bundle, which is the core component of the plate-fin heat exchanger. On this basis, with necessary components such as end heads, nozzles, and supports, a complete plate-fin heat exchanger is finally formed.

[0003] Currently, the commonly used flow guiding plates in plate-fin heat exchangers are mainly straight wave fins and sawtooth wave fins. The straight wave fins have a relatively small pressure drop when the fluid passes through, which can effectively reduce the energy loss during fluid transportation; the sawtooth wave fins, on the other hand, perform well in heat transfer performance and can achieve heat transfer more efficiently. However, the resistance of the sawtooth wave fins is relatively large, which is 2 - 3 times that of the straight wave fins. At the same time, both of these fins have directionality, and in the entire heat exchanger, only a single direction can be used as the inlet and outlet. This characteristic leads to the easy occurrence of flow dead zones inside the heat exchanger, making the fluid in some areas unable to fully participate in heat exchange, thereby reducing the overall heat transfer efficiency and energy utilization efficiency of the heat exchanger, and restricting the application of plate-fin heat exchangers in some scenarios with high requirements for heat transfer efficiency and uniform fluid distribution.

[0004] Therefore, it is of great practical significance to develop a plate-fin heat exchanger structure that can improve fluid distribution, reduce flow dead zones, and at the same time have good heat transfer performance. Summary of the Invention

[0005] In view of this, the present invention provides a fin structure and a heat exchanger to solve the problem of easy occurrence of flow dead zones inside traditional heat exchangers.

[0006] In a first aspect, the present invention provides a fin structure, including fin units distributed in several columns, and all the fin units are connected to form a plate-shaped fin: any one of the fin units includes a bottom plate and a guiding shell formed on the upper side of the bottom plate. The inside of the guiding shell is hollow, and the guiding shell is provided with a plurality of first openings arranged along a first direction, a plurality of second openings arranged along the reverse direction of the first direction, a plurality of third openings arranged along a second direction, and a plurality of fourth openings arranged along the reverse direction of the second direction. All four openings are communicated with the inside of the guiding shell, and the straight line where the first direction is located intersects with the straight line where the second direction is located.

[0007] Beneficial effects: The fin is composed of several columns of fin units connected together. Among them, any one of the fin units is mainly composed of a bottom plate and a guiding shell firmly formed on the upper side of the bottom plate. The inside of the guiding shell is a hollow structure, and this hollow space is designed specifically for the smooth flow of liquid and is the key channel for realizing efficient heat exchange. The guiding shell is provided with a first opening, a second opening, a third opening, and a fourth opening, and all four openings are communicated with the inside of the guiding shell. During actual use, the liquid can flow into or out of the guiding shell flexibly through these four openings according to the heat exchange requirements. Since most conventional fins have directionality and can only have a single direction as the inlet and outlet in the entire heat exchanger, in the present invention, the first opening is arranged along the first direction, the second opening is arranged along the reverse direction of the first direction, the third opening is arranged along the second direction, the fourth opening is arranged along the reverse direction of the second direction, and the straight line where the first direction is located intersects with the straight line where the second direction is located. Therefore, the liquid can enter the inside of the fin unit from at least the first direction, the reverse direction of the first direction, the second direction, and the reverse direction of the second direction, that is, it is realized that the fin can be selected as the inlet and outlet from multiple directions. No matter which direction is selected, the liquid can flow normally, which can reduce the flow dead zone in the heat exchanger, increase the effective heat exchange area and heat exchange efficiency, and make the design of the plate-fin heat exchanger more convenient.

[0008] In an alternative embodiment, the first opening and the second opening are arranged on the same side of the fin unit, and the cross-sections of the first opening and the second opening are parallel to each other.

[0009] Beneficial effects: The first opening and the second opening are arranged on the left side of the fin unit, and the first opening and the second opening can be regarded as the openings on two opposite sides of the same cavity. The liquid entering this cavity from the first opening can directly flow out from the second opening, or the liquid entering this cavity from the second opening can also directly flow out from the first opening. Of course, this does not limit that the liquid entering the guiding shell from the first opening can only flow out from the second opening. All four openings are communicated with each other. This is only an introduction to a liquid flow mode.

[0010] In an alternative embodiment, the cross-sectional area of the first opening is larger than the cross-sectional area of the second opening.

[0011] In an alternative embodiment, the first opening and the second opening are arranged in a staggered manner. As described above, the first opening and the second opening can be regarded as the openings on two opposite sides of the same cavity. There are multiple such cavities in the length direction of the fin unit, so that the first opening and the second opening are arranged in a staggered manner.

[0012] In an alternative embodiment, the third opening and the fourth opening are arranged on the same side of the fin unit, and the first opening and the third opening are on opposite sides of the fin unit.

[0013] Beneficial effects: The first opening is the same as the second opening, and the third opening and the fourth opening are provided on the left side of the fin unit. Moreover, the third opening and the fourth opening can be regarded as the openings on two opposite sides of the same cavity. The liquid entering the cavity from the third opening can directly flow out from the fourth opening, or the liquid entering the cavity from the fourth opening can also directly flow out from the third opening.

[0014] In an alternative embodiment, the first integral formed by the first opening and the second opening has the same structure as the second integral formed by the third opening and the fourth opening. The two integrals are arranged staggeredly in the length direction of the fin unit, and the first opening in the first integral is located in the middle of the third opening and the fourth opening in the second integral.

[0015] Beneficial effects: The first integral refers to the first opening, the second opening, and the side wall connecting the first opening and the second opening; similarly, the second integral refers to the third opening, the fourth opening, and the side wall connecting the third opening and the fourth opening. By arranging the two integrals staggeredly in the length direction of the fin unit and having the first opening in the first integral located in the middle of the third opening and the fourth opening in the second integral, in two adjacent fin units, the first opening in one fin unit is located in the middle of the third opening and the fourth opening in the other fin unit. This enables the liquid in one fin unit to quickly pass through the third opening and the fourth opening in the other fin unit after flowing out from its first opening. Further, if two adjacent fin units are completely aligned, the distance between the first opening and the third opening in the two fin units is too small, affecting the flow of the liquid.

[0016] In an alternative embodiment, the included angle between the first direction and the horizontal direction is α, and 0° < α < 90°.

[0017] Beneficial effects: By setting 0° < α < 90° and the first direction being symmetric with the second direction about the middle line in the length direction of the fin unit, it can be ensured that the four opening directions of the fin unit are all different.

[0018] In an alternative embodiment, there is a gap between two adjacent columns of fin units.

[0019] Beneficial effects: The gap between two adjacent columns of fin units also serves as the liquid flow channel on the fins. At the same time, by providing a gap between two adjacent columns of fin units, in addition to using this gap as the liquid flow channel, it can also prevent the distance between two adjacent columns of fin units from being too close, thereby restricting the flow of the liquid on the fins.

[0020] In an alternative embodiment, the fin units on the fins are aligned both vertically and horizontally, so as to ensure that the liquid inlet directions at the same positions on two fin units in the same row are the same. This setting can avoid the situation where the adjacent fin units block the inlet of the opening due to the staggered arrangement.

[0021] Second, the present invention also provides a heat exchanger, including:

[0022] Two partition plates;

[0023] A fin structure disposed between the two partition plates;

[0024] Two side strips connected to opposite sides of the fin structure, and the other two sides of the fin structure are for the inflow or outflow of the liquid.

[0025] Beneficial effects: The liquid flow inside the heat exchanger using the above fin structure is more uniform, the flow dead zone inside the heat exchanger can be reduced, the effective heat transfer area and heat transfer efficiency can be improved, and the design of the plate-fin heat exchanger is more convenient. Moreover, there is no flow dead zone in this fin, and it can flow in from any direction, and can be used integrally in the heat exchanger without the need to be divided into multiple sections of fins for combined use. Description of the Drawings

[0026] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required to be used in the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0027] Figure 1 It is a schematic structural diagram of a fin structure in an embodiment of the present invention;

[0028] Figure 2 It is a top view of a fin structure in an embodiment of the present invention;

[0029] Figure 3 It is a schematic structural diagram of a heat exchanger in an embodiment of the present invention.

[0030] Description of the Reference Numerals:

[0031] 1, bottom plate; 2, guiding housing; 3, first opening; 4, second opening; 5, third opening; 6, fourth opening; 7, partition plate; 8, side strip. Specific Embodiments

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0033] In the field of heat exchange equipment, plate-fin heat exchangers have been widely used due to their high heat exchange performance and compact structural design. A plate-fin heat exchanger usually consists of side plates, partition plates, fins, and seals. The sandwich formed by placing fins, flow guiding sheets, and seals between two adjacent partition plates is called a channel. Stacking these channels according to different fluid flow modes and welding them into a whole forms a plate bundle, which is the core component of the plate-fin heat exchanger. On this basis, with necessary components such as end covers, nozzles, and supports, a complete plate-fin heat exchanger is finally formed.

[0034] Currently, the commonly used flow guiding plates in plate-fin heat exchangers are mainly straight fin and serrated fin. The straight fin has a relatively small pressure drop when the fluid passes through, which can effectively reduce the energy loss during fluid transportation; the serrated fin performs well in heat exchange performance and can achieve heat transfer more efficiently. However, the resistance of the serrated fin is relatively large, 2-3 times that of the straight fin. At the same time, both of these fins have directionality, and in the whole heat exchanger, only a single direction can be used as the inlet and outlet. This characteristic leads to the easy occurrence of flow dead zones inside the heat exchanger, making the fluid in some areas unable to fully participate in heat exchange, thereby reducing the overall heat exchange efficiency and energy utilization efficiency of the heat exchanger, and restricting the application of plate-fin heat exchangers in some scenarios with high requirements for heat exchange efficiency and uniform fluid distribution.

[0035] The following will describe the embodiments of the present invention in conjunction with Figures 1 to 3 , the embodiments of the present invention are described.

[0036] According to an embodiment of the present invention, on the one hand, a fin structure is provided, as shown in Figure 1 , which includes fin units distributed in several columns, and all the fin units are connected to form a plate-shaped fin: any fin unit includes a bottom plate 1 and a guiding shell 2 formed on the upper side of the bottom plate 1. The inside of the guiding shell 2 is hollow, and the guiding shell 2 is provided with a plurality of first openings 3 arranged along the first direction (the direction indicated by the arrow c in Figure 2 ), a plurality of second openings 4 arranged along the reverse direction of the first direction, a plurality of third openings 5 arranged along the second direction (the direction indicated by the arrow d in Figure 2 ), and a plurality of fourth openings 6 arranged along the reverse direction of the second direction. All four openings are communicated with the inside of the guiding shell 2, and the straight line where the first direction is located intersects with the straight line where the second direction is located.

[0037] In this embodiment, the fin is composed of several columns of fin units connected together. Among them, any fin unit mainly consists of a bottom plate 1 and a guiding shell 2 stably formed on the upper side of the bottom plate 1. The inside of the guiding shell 2 is a hollow structure, and this hollow space is designed specifically for the smooth flow of liquid and is the key channel for realizing efficient heat exchange. As Figure 1 shown, the guiding shell 2 is provided with a first opening 3, a second opening 4, a third opening 5, and a fourth opening 6. All four openings are in communication with the inside of the guiding shell 2. During actual use, the liquid can flow into or out of the guiding shell 2 through these four openings according to the heat exchange requirements. Since most conventional fins have directionality and can only have a single direction as the inlet and outlet in the entire heat exchanger, in this embodiment, the first opening 3 is arranged along the first direction, the second opening 4 is arranged along the reverse direction of the first direction, the third opening 5 is arranged along the second direction, and the fourth opening 6 is arranged along the reverse direction of the second direction, and the straight line where the first direction is located intersects the straight line where the second direction is located. Therefore, the liquid can at least enter the fin unit from the first direction, the reverse direction of the first direction, the second direction, and the reverse direction of the second direction, that is, it is realized that the fin can be selected as the inlet and outlet from multiple directions. No matter which direction is selected, the liquid can flow normally, which can reduce the flow dead zone in the heat exchanger, increase the effective heat exchange area and heat exchange efficiency, and make the design of the plate-fin heat exchanger more convenient.

[0038] Of course, as Figure 1 shown, the four opening directions mentioned in this embodiment are not absolute and precise direction limitations, but approximately refer to the extension direction of the opening side wall. In the actual hydrodynamic environment, due to the combined influence of various factors on the liquid flow, such as the initial flow rate of the fluid, the convective effect caused by the temperature difference, and the pressure distribution inside the heat exchanger, the liquid inlet direction is not necessarily strictly along the extension direction of the opening side wall. When the included angle between the liquid inlet direction and the opening cross-section is an acute angle, the liquid can still enter the fin unit smoothly along this opening. Therefore, during actual use, the liquid inlet direction of the fin unit in this embodiment has extremely high flexibility, far from being limited only to the extension direction of the side walls of the first opening 3, the second opening 4, the third opening 5, and the fourth opening 6. It can adapt to the liquid inlet conditions in more directions, providing rich and diverse possibilities for the fluid flow in the heat exchange process, and further strengthening the performance advantages of the plate-fin heat exchanger.

[0039] In one embodiment, the first opening 3 and the second opening 4 are arranged on the same side of the fin unit, and the cross-sections of the first opening 3 and the second opening 4 are parallel to each other.

[0040] As Figure 1As shown, the first opening 3 and the second opening 4 are provided on the left side of the fin unit, and the first opening 3 and the second opening 4 can be regarded as the openings on two opposite sides of the same cavity. The liquid entering this cavity from the first opening 3 can directly flow out from the second opening 4, or the liquid entering this cavity from the second opening 4 can also directly flow out from the first opening 3. Of course, this does not limit that the liquid entering the guiding housing 2 from the first opening 3 can only flow out from the second opening 4. The four openings are all interconnected, and this is only to introduce a liquid flow mode.

[0041] As Figure 1 shown, a side wall a of the guiding housing 2 is provided between two adjacent first openings 3 and second openings 4. This side wall a is directly and smoothly transitioned with the side walls of the first opening 3 and the second opening 4. When the liquid flows to this side wall a, after being blocked by this side wall a, the liquid can directly flow into the guiding housing 2 through the first opening 3 and the second opening 4, reducing the flow dead zone.

[0042] In one embodiment, the cross-sectional area of the first opening 3 is larger than that of the second opening 4.

[0043] In one embodiment, the first opening 3 and the second opening 4 are arranged staggeredly. As described above, the first opening 3 and the second opening 4 can be regarded as the openings on two opposite sides of the same cavity. There are multiple such cavities in the length direction of the fin unit, so that the first opening 3 and the second opening 4 are arranged staggeredly.

[0044] In one embodiment, the third opening 5 and the fourth opening 6 are provided on the same side of the fin unit, and the first opening 3 and the third opening 5 are on the opposite sides of the fin unit. Similar to the first opening 3 and the second opening 4, the third opening 5 and the fourth opening 6 are provided on the left side of the fin unit, and the third opening 5 and the fourth opening 6 can be regarded as the openings on two opposite sides of the same cavity. The liquid entering this cavity from the third opening 5 can directly flow out from the fourth opening 6, or the liquid entering this cavity from the fourth opening 6 can also directly flow out from the third opening 5. Of course, this does not limit that the liquid entering the guiding housing 2 from the third opening 5 can only flow out from the fourth opening 6. The four openings are all interconnected, and this is only to introduce a liquid flow mode. At the same time, the first opening 3 and the third opening 5 are on the opposite sides of the fin unit, and this design can increase the liquid inlet direction of the guiding housing 2. Similarly, a side wall b of the guiding housing 2 is provided between two adjacent third openings 5 and fourth openings 6. This side wall b is directly and smoothly transitioned with the side walls of the third opening 5 and the fourth opening 6. When the liquid flows to this side wall b, after being blocked by this side wall b, the liquid can directly flow into the guiding housing 2 through the third opening 5 and the fourth opening 6, reducing the flow dead zone.

[0045] In one embodiment, the first overall structure formed by the first opening 3 and the second opening 4 is the same as the second overall structure formed by the third opening 5 and the fourth opening 6. The two overall structures are staggered in the length direction of the fin unit, and the first opening 3 in the first overall structure is located in the middle of the third opening 5 and the fourth opening 6 in the second overall structure. As Figure 1 shown, the first overall structure refers to the first opening 3, the second opening 4, and the side wall connecting the first opening 3 and the second opening 4; similarly, the second overall structure refers to the third opening 5, the fourth opening 6, and the side wall connecting the third opening 5 and the fourth opening 6. By setting the two overall structures to be staggered in the length direction of the fin unit and the first opening 3 in the first overall structure to be located in the middle of the third opening 5 and the fourth opening 6 in the second overall structure, as Figure 1 shown, in two adjacent fin units, the first opening 3 in one fin unit is located in the middle of the third opening 5 and the fourth opening 6 in the other fin unit. This enables the liquid in one fin unit to flow out from its first opening 3 and then quickly pass through the third opening 5 and the fourth opening 6 in the other fin unit and enter this fin unit. Further, if two adjacent fin units are completely aligned, the distance between the first opening 3 and the third opening 5 in the two fin units is too small, affecting the flow of the liquid.

[0046] In one embodiment, the angle between the first direction and the horizontal direction is α, and 0° < α < 90°. By setting 0° < α < 90° and the first direction and the second direction to be symmetric about the middle line of the length direction of the fin unit, it can be ensured that the four opening directions of the fin unit are all different.

[0047] In one embodiment, the angle between the first direction and the horizontal direction is 45°. Alternatively, in another embodiment, the angle between the first direction and the horizontal direction is 67.5°. Furthermore, in another embodiment, the angle between the first direction and the horizontal direction is 75°.

[0048] In one embodiment, there is a gap between two adjacent columns of fin units. The gap between two adjacent columns of fin units also serves as a liquid flow channel on the fin. At the same time, by providing a gap between two adjacent columns of fin units, in addition to using this gap as a liquid flow channel, it can also prevent the distance between two adjacent columns of fin units from being too close, thereby restricting the flow of the liquid on the fin.

[0049] In one embodiment, as Figure 1 shown, the fin units on the fin are aligned both vertically and horizontally to ensure that the liquid inlet directions of the liquid passing-through housings at the same position on two fin units in the same row are the same. This setting can prevent the occurrence of the situation where the liquid inlet of the blocking opening exists between adjacent fin units due to the staggered setting.

[0050] The fin structure provided in this embodiment has a guiding housing 2 formed by bending the bottom plate 1 upward. Further, the entire plate-shaped fin can be integrated, and all the guiding housings 2 are formed by bending upward at some parts of the fin. The fin can be made of stainless steel, titanium, copper or other materials.

[0051] The fin structure provided in this embodiment has a fin resistance that is 1.2 - 1.3 times that of a straight-wave fin and still retains the structural characteristics of an intermittent fin. This structure can periodically disrupt the fluid boundary layer in the fin channel, keeping the velocity and temperature boundary layers in a developing state, having a relatively high heat transfer coefficient, and being a high-efficiency fin, which enriches the types of fins that can be used in plate-fin heat exchangers.

[0052] According to an embodiment of the present invention, on the other hand, a heat exchanger is also provided, as Figure 3 shown, including two partitions 7, a fin structure disposed between the two partitions 7, and two side strips 8. The two partitions 7 and the two side strips 8 form a placement cavity for placing the fin structure. After the above components are installed, the fin structure serves as liquid inlets and outlets on both sides of the side strips 8. Using the above fin structure, the liquid flow inside the heat exchanger is more uniform, the flow dead zones inside the heat exchanger can be reduced, the effective heat transfer area and heat transfer efficiency can be improved, and the design of the plate-fin heat exchanger is more convenient. Moreover, there are no flow dead zones in this fin, and it can be inlet from any direction, and can be used integrally in the heat exchanger without the need to be divided into multiple sections of fins for cooperation.

[0053] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A fin structure, characterized in that: It includes fin units distributed in several rows, and all the fin units are connected to form a plate-shaped fin: Any of the fin units comprises a base plate (1) and a guide shell (2) formed on the upper side of the base plate (1); the interior of the guide shell (2) is hollow; the guide shell (2) is provided with a plurality of first openings (3) arranged along a first direction, a plurality of second openings (4) arranged in a direction opposite to the first direction, a plurality of third openings (5) arranged in a direction opposite to the second direction, and a plurality of fourth openings (6) arranged in a direction opposite to the second direction; the four openings are all connected to the interior of the guide shell (2), and the straight line on which the first direction is located intersects with the straight line on which the second direction is located.

2. The fin structure according to claim 1, characterized in that: The first opening (3) and the second opening (4) are arranged on the same side of the fin unit, and the cross sections of the first opening (3) and the second opening (4) are parallel.

3. The fin structure according to claim 2, characterized in that: The first openings (3) and the second openings (4) are arranged alternately.

4. The fin structure according to claim 3, characterized in that: The cross-sectional area of ​​the first opening (3) is greater than the cross-sectional area of ​​the second opening (4).

5. The fin structure according to any one of claims 2 to 4, characterized in that: The third opening (5) and the fourth opening (6) are arranged on the same side of the fin unit, and the first opening (3) and the third opening (5) are located on opposite sides of the fin unit.

6. The fin structure according to claim 5, characterized in that: The first whole formed by the first opening (3) and the second opening (4) has the same structure as the second whole formed by the third opening (5) and the fourth opening (6); the two wholes are arranged alternately in the length direction of the fin unit, and the first opening (3) in the first whole is located between the third opening (5) and the fourth opening (6) in the second whole.

7. The fin structure according to claim 6, characterized in that: The angle between the first direction and the horizontal direction is α, and 0°<α<90°.

8. The fin structure according to claim 7, characterized in that: α is 45°, 67.5° or 75°.

9. The fin structure according to any one of claims 1 to 4, characterized in that: There is a gap between two adjacent rows of fin units.

10. A heat exchanger, characterized in that: include: two partitions (7); A fin structure according to any one of claims 1 to 9 arranged between two partitions (7); Two side strips (8) are connected to two opposite sides of the fin structure, and the other two sides of the fin structure are arranged for the inflow or outflow of liquid.

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