Alternating flow heat exchanger

Abstract

The invention relates to the technical field of heat exchangers, and provides an alternating flow heat exchanger which comprises a plurality of fin plates arranged at intervals in the first direction, and each fin plate is provided with a plurality of airflow holes; every two adjacent fin plates are arranged at intervals, so that gas entering the gas flow holes cannot continuously and directly enter the adjacent gas flow holes in the height direction, but diffuses to the periphery to enter the gas flow channel, a plurality of independent gas flow sections are formed, each section of gas flow generates an inlet effect when entering the gas flow holes, and therefore the gas flow efficiency is improved. Therefore, the overall heat transfer efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of heat exchangers, and in particular to an alternating flow heat exchanger. Background Art

[0002] Alternating flow heat-to-work conversion systems include Stirling engines, Stirling refrigerators, thermoacoustic engines and thermoacoustic refrigerators, which have the advantages of high efficiency, high reliability and compact structure. They have great application potential in aerospace, military, biomedicine and other fields. As a key component for energy conversion, the quality of heat transfer of alternating flow heat exchangers has an important influence on the efficiency of the system. At present, alternating flow alternating flow heat exchangers mainly adopt traditional fin-type heat exchange structures and tube bundle-type heat exchange structures.

[0003] However, since the heat transfer coefficient on the gas side is more than one order of magnitude smaller than that of the liquid phase heat carrier fluid, the gas side heat transfer temperature difference of the alternating flow heat exchanger is large, further affecting the system heat transfer efficiency and overall performance. Existing measures to improve the heat transfer effect include increasing the heat transfer area or reducing the hydraulic diameter, but the current alternating flow heat exchanger gas side area has reached its limit, and the hydraulic diameter is close to the optimal value. Further reduction will increase resistance loss and cannot improve the overall efficiency. Summary of the invention

[0004] The present invention provides an alternating flow heat exchanger, which is used to solve the problem of poor heat exchange mode and effect on the gas side of the alternating flow heat exchanger in the prior art.

[0005] The present invention provides an alternating flow heat exchanger, comprising: A plurality of fin plates are provided, wherein the plurality of fin plates are arranged at intervals along a first direction, and each of the fin plates is provided with a plurality of air flow holes.

[0006] The alternating flow heat exchanger provided according to the present invention also includes a partition, which is arranged between two adjacent fin plates, and the partition partially overlaps with the fin plate, so as to create a gap between the areas where the air flow holes on the two adjacent fin plates are located, and the inner end of the partition and the space enclosed by the two adjacent fin plates form a gas flow channel, and the gas flow channel is connected to the air flow holes.

[0007] According to the alternating flow heat exchanger provided by the present invention, the air flow holes between two adjacent fin plates correspond to each other one by one.

[0008] According to the alternating flow heat exchanger provided by the present invention, the air flow holes between two adjacent fin plates are arranged in a staggered manner.

[0009] According to the alternating flow heat exchanger provided by the present invention, a support member is provided between two adjacent fin plates, and the support member is connected to the inner side ends of the fin plates.

[0010] According to the alternating flow heat exchanger provided by the present invention, the fin plate and the partition plate are both annular structures, and a plurality of the air flow holes are arranged on the inner side of the fin plate at equal intervals along the circumferential direction; the outer end of the partition plate is located on the outer side of the fin plate, and the space enclosed by the outer ends of two adjacent partition plates and the fin plate forms a liquid-phase heat-carrying fluid flow channel for the flow of the heat-carrying fluid.

[0011] According to the alternating flow heat exchanger provided by the present invention, the air flow holes are strip holes, and the length direction of the strip holes is parallel to the radial direction of the fin plate.

[0012] According to the alternating flow heat exchanger provided by the present invention, the portion of the partition plate located outside the fin plate forms an enhanced fin on the heat-carrying fluid side.

[0013] According to the alternating flow heat exchanger provided by the present invention, the thickness of the support member is 0.5-5 mm.

[0014] The alternating flow heat exchanger provided according to the present invention further includes a sleeve and a plurality of circular tubes, the fin plate is axially arranged in each of the circular tubes, a plurality of the air flow holes are circumferentially arranged on the fin plate, and the air flow holes on two adjacent fin plates are staggered.

[0015] The present invention provides an alternating flow heat exchanger, which arranges two adjacent fin plates at intervals. Compared with the traditional scheme, the gas entering the air flow hole of the present invention cannot continue to directly enter the adjacent air flow hole along the height direction, but will diffuse to the surroundings, resulting in the formation of multiple independent air flow segments. Each air flow segment will produce an inlet effect when entering the air flow hole again. The inlet effect makes the heat transfer coefficient significantly increase each time the air flow enters a new air flow hole, thereby improving the overall heat transfer efficiency, helping to quickly homogenize the temperature distribution of the fluid, and reducing the unevenness of the temperature gradient. The inlet effect will also cause the fluid to generate more turbulence near the inlet, thereby enhancing the contact between the fluid and the heat exchange surface, and further enhancing the heat transfer effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a cross-sectional view of an alternating flow heat exchanger provided by an embodiment of the present invention.

[0018] Figure 2It is a cross-sectional view of an alternating flow heat exchanger provided by another embodiment of the present invention.

[0019] Figure 3 It is a schematic diagram of the three-dimensional structure of the alternating flow heat exchanger provided in an embodiment of the present invention.

[0020] Figure 4 It is a cross-sectional view of an alternating flow heat exchanger provided by another embodiment of the present invention.

[0021] Figure 5 It is a schematic diagram of the structure inside the circular tube provided by an embodiment of the present invention.

[0022] Figure 6 It is a cross-sectional view of an alternating flow heat exchanger in the prior art.

[0023] Reference numerals: 1. Fin plate; 2. Partition plate; 3. Gas flow channel; 4. Support member; 5. Liquid heat carrier flow channel; 6. Sleeve; 7. Round tube; 8. Air flow hole; 9. Heat exchange fin. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] like Figure 6 As shown, it is a traditional alternating flow heat exchanger in the prior art, in which a large number of heat exchange fins 9 are processed on a heat conductive substrate by wire cutting, and a gas flow channel 3 is formed between the inner radial fins. The working gas in the alternating flow heat-to-power conversion system is usually helium, and a liquid phase heat carrier fluid flow channel 5 is arranged along the circumferential direction on the outer side. Usually, there is a ring sleeve on the outer circumference of the alternating flow heat exchanger, and the ring sleeve has an inlet and outlet. The heat carrier fluid flows along the circumferential direction of the liquid phase heat carrier fluid flow channel 5, enters from one side of the circumference, and flows out from the other side. The heat exchange principle of this alternating flow heat exchanger is heat exchange between the heat carrier fluid and the wall of the flow channel, and the heat or cold is transferred to the fins, and then further transferred to the working gas inside the system. Because the heat transfer coefficient between the working gas and the wall is small and the heat exchange temperature difference on the gas side is large, the gas side heat exchange performance of the alternating flow heat exchanger is not ideal.

[0026] Combine the following Figure 1-Figure 5 An alternating flow heat exchanger according to the invention is described.

[0027] This embodiment provides an alternating flow heat exchanger, including a fin plate 1, wherein a plurality of fin plates 1 are provided, and the plurality of fin plates 1 are stacked along a first direction, and a plurality of air flow holes 8 are provided on the inner side of each fin plate 1, wherein the first direction is a height direction, i.e., a thickness direction of the fin plate 1.

[0028] It can be seen from the above scheme that there is a gap between the two fin plates 1 of the present invention. Compared with the traditional scheme, the gas entering the air flow hole 8 of the present invention cannot continue to directly enter the adjacent air flow hole 8 along the height direction, but will diffuse to the surroundings, resulting in the formation of multiple independent air flow segments. Each air flow will produce an inlet effect when entering the air flow hole 8 again. The inlet effect makes the heat transfer coefficient significantly increase each time the air flow enters a new air flow hole 8, thereby improving the overall heat transfer efficiency, helping to quickly homogenize the temperature distribution of the fluid, and reducing the unevenness of the temperature gradient. The inlet effect will also cause the fluid to generate more turbulence near the inlet, thereby enhancing the contact between the fluid and the heat exchange surface, and further enhancing the heat transfer effect.

[0029] It should be noted that the inlet effect, also known as the Barus effect, refers to the phenomenon that molten polymer or fluid is oriented and elastically stores energy when passing through a pipe with a changing cross-section. It belongs to the prior art, and the principle is not the focus of this article and will not be elaborated here.

[0030] In some embodiments, a partition plate 2 is also included, which is arranged between two adjacent fin plates 1, and the partition plate 2 partially overlaps with the fin plate 1, so that the area where the air flow holes 8 on the two adjacent fin plates 1 are located can be separated, and the inner end of the partition plate 2 and the space enclosed by the two adjacent fin plates 1 form a gas flow channel 3, and the gas flow channel 3 is connected to the air flow holes 8.

[0031] With such arrangement, the gas entering the air flow hole 8 of the present invention cannot continue to directly enter the adjacent air flow hole 8 along the height direction, but will diffuse to the surrounding and enter the gas flow channel 3, resulting in the formation of multiple independent air flow segments, and each air flow segment will produce an inlet effect when entering the air flow hole 8 again.

[0032] like Figure 1 As shown, in some embodiments, the air flow holes 8 between two adjacent fin plates 1 correspond one to one. After the two adjacent fin plates 1 are separated by the partition plate 2, the gas entering the air flow hole 8 cannot continue to directly enter the corresponding upper and lower air flow holes 8 along the height direction, but will diffuse to the surroundings and enter the gas flow channel 3, thereby increasing the heat exchange area and forming multiple independent air flow segments. Each air flow segment will produce an inlet effect when entering the air flow hole 8 again, thereby enhancing the heat transfer effect of the air flow.

[0033] In other embodiments, the air flow holes 8 between two adjacent fin plates 1 are arranged in a staggered manner, such as Figure 2As shown, after two adjacent fin plates 1 are separated by the partition plate 2, the flow channels are further disturbed by staggered arrangement of the air flow holes 8 on the adjacent fin plates 1, thereby enhancing the heat exchange effect.

[0034] In this embodiment, a support member 4 is provided between two adjacent fin plates 1, and the support member 4 is connected to the inner end of the fin plate 1. In this arrangement, since the fluid flowing through the inner side of the fin plate 1 for heat exchange is mostly high-pressure gas, the arrangement of the support thin member can prevent the fin from being deformed and bent due to the impact of the airflow during the flow of high-pressure gas, thereby improving the strength of the overall structure.

[0035] like Figure 1-Figure 3 As shown, in this embodiment, the fin plate 1 and the partition plate 2 are both annular structures, and a plurality of air flow holes 8 are arranged on the inner side of the fin plate 1 at equal intervals along the circumferential direction. Correspondingly, the support member 4 is a support ring, and the material is the same as that of the fin plate 1, and the thickness is 0.5-5mm. The specific thickness is designed according to the size of the actual alternating flow heat exchanger. The materials of the fin plate 1, the partition plate 2 and the support member 4 are selected from materials with good thermal conductivity and mechanical strength, such as copper, stainless steel, aluminum alloy, etc.

[0036] Optionally, the air flow holes 8 are strip holes, and the length direction of the strip holes is the same as the radial direction of the fin plate 1 .

[0037] like Figure 1-Figure 3 As shown, the outer end of the partition 2 is located on the outer side of the fin plate 1, and the space enclosed by the two adjacent partitions 2 and the outer ends of the fin plates 1 forms a liquid-phase heat-carrying fluid flow channel 5 for the flow of the heat-carrying fluid. The heat-carrying fluid flows along the circumferential direction of the liquid-phase heat-carrying fluid flow channel 5, enters from an opening on one side of the circumference, and flows out from an opening on the other side; that is, the annular partition 2 is cocentrically arranged with the annular fin plate 1 and is staggeredly connected, that is, the partition 2 and the fin plate 1 partially overlap, and the outer end of the partition 2 is located on the outer side of the fin plate 1, and the inner end of the partition 2 is located in the space between the two adjacent fin plates 1, thereby achieving a gap in the area where the air flow holes 8 on the two adjacent fin plates 1 are located, and the inner end of the partition 2 and the space enclosed by the two adjacent fin plates 1 form a gas flow channel 3, and the gas flow channel 3 is connected to each air flow hole 8; the outer end of the fin plate 1 and the space enclosed by the two adjacent outwardly extending partitions 2 form a liquid-phase heat-carrying fluid flow channel 5. A liquid inlet is provided on one side of the liquid phase heat transfer fluid flow channel 5, and a liquid outlet is provided on the other side opposite thereto, so that the heat fluid flows along the circumferential direction of the liquid phase heat transfer fluid flow channel 5, enters from one side of the circumference, and flows out from the other side.

[0038] Furthermore, the fin plate 1 and the partition plate 2 are connected by welding, and the welding methods include but are not limited to brazing, diffusion welding, etc., to ensure that the gas flow channel 3 and the heat carrier fluid flow channel are not connected, improve the reliability of the sealing connection, and prevent air leakage.

[0039] In this embodiment, the portion of the partition plate 2 located outside the fin plate 1 forms a reinforcing fin on the heat transfer fluid side to increase the heat exchange area and heat exchange efficiency with the heat transfer fluid.

[0040] Reference Figure 4 and Figure 5 The embodiment of the present invention also provides an alternating flow heat exchanger, which is a tube bundle heat exchanger, including a sleeve 6 and a plurality of round tubes 7 arranged in the sleeve 6. A plurality of fin plates 1 are arranged in the axial direction in the round tube 7. The fin plates 1 are circular and can be welded to the inner wall of the round tube 7. A plurality of airflow holes 8 are arranged in the circumferential direction on each fin plate 1. Each airflow hole 8 extends in the radial direction, and the airflow holes 8 on two adjacent fin plates 1 are arranged alternately; that is, the fin plates 1 of the adjacent layer can be rotated by a certain angle so that they are arranged alternately with the airflow holes 8 on the fin plates 1 of the current layer, thereby forming a plurality of independent airflow sections. When working, the airflow flows in the round tube 7, and the heat-carrying fluid flows in the sleeve 6 outside the round tube 7. The sleeve 6 is provided with an inlet and an outlet. The external fluid passes through the tube bundle and exchanges heat with the high-pressure gas working medium in the tube bundle, and releases heat or cold to the gas working medium.

[0041] In this arrangement, by welding the fin plate 1 inside the circular tube 7, the heat exchange area on the gas side is increased, the heat exchange effect is improved, and by arranging the fin plates 1 at intervals and in staggered rows, a plurality of independent flow channels are formed, interrupting the continuous flow of the airflow along the axial direction, causing the airflow to change its flow direction each time it enters the next flow channel, so that an inlet effect is generated each time the airflow passes through a layer of the fin plate 1, thereby improving the heat exchange effect.

[0042] The present invention utilizes the inlet effect to enhance heat transfer in the alternating flow heat exchanger. The fin plates 1 are spaced apart to create discontinuities between the fin flow channels. The gas cannot continue to directly enter the adjacent air flow holes 8 along the height direction, but diffuses to the surroundings into the gas flow channel 3, resulting in the formation of multiple independent air flow segments. Each air flow segment will generate an inlet effect when entering the air flow hole 8, and the fin plates 1 can be staggered to further disrupt the flow channel and enhance the heat exchange effect.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An alternating flow heat exchanger, characterized in that: include: A plurality of fin plates (1) are provided, wherein the plurality of fin plates (1) are arranged at intervals along a first direction, and each of the fin plates (1) is provided with a plurality of air flow holes (8).

2. The alternating flow heat exchanger according to claim 1, characterized in that: The invention also comprises a partition plate (2), wherein the partition plate (2) is arranged between two adjacent fin plates (1), and the partition plate (2) partially overlaps with the fin plate (1), so as to generate a gap between the areas where the air flow holes (8) on the two adjacent fin plates (1) are located, and the inner side end of the partition plate (2) and the space enclosed by the two adjacent fin plates (1) form a gas flow channel (3), and the gas flow channel (3) is connected to the air flow hole (8).

3. The alternating flow heat exchanger according to claim 2, characterized in that: The air flow holes (8) between two adjacent fin plates (1) correspond one to one.

4. The alternating flow heat exchanger according to claim 2, characterized in that: The air flow holes (8) between two adjacent fin plates (1) are arranged in a staggered manner.

5. The alternating flow heat exchanger according to claim 2, characterized in that: A support member (4) is provided between two adjacent fin plates (1), and the support member (4) is connected to the inner side ends of the fin plates (1).

6. The alternating flow heat exchanger according to claim 2, characterized in that: The fin plate (1) and the partition plate (2) are both annular structures, and a plurality of the air flow holes (8) are arranged at equal intervals along the circumferential direction on the inner side of the fin plate (1); the outer end of the partition plate (2) is located on the outer side of the fin plate (1), and the space enclosed by the outer ends of two adjacent partition plates (2) and the fin plate (1) forms a liquid phase heat transfer fluid flow channel (5) for the flow of the heat transfer fluid.

7. The alternating flow heat exchanger according to claim 5, characterized in that: The air flow holes (8) are strip-shaped holes, and the length direction of the strip-shaped holes is parallel to the radial direction of the fin plate (1).

8. The alternating flow heat exchanger according to claim 2, characterized in that: The portion of the partition plate (2) located outside the fin plate (1) forms a strengthening fin on the heat transfer fluid side.

9. The alternating flow heat exchanger according to claim 5, characterized in that: The support member (4) has a thickness of 0.5-5 mm.

10. The alternating flow heat exchanger according to claim 1, characterized in that: It also comprises a sleeve (6) and a plurality of circular tubes (7), wherein the fin plate (1) is axially arranged in each of the circular tubes (7), and a plurality of air flow holes (8) are arranged on the fin plate (1) along a circumferential direction, and the air flow holes (8) on two adjacent fin plates (1) are arranged in a staggered manner.

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