Countercurrent heat exchanger

Abstract

The present invention relates to the field of heat exchange technology, and discloses a countercurrent heat exchanger, comprising a heat exchange plate group and a distributor group, wherein the heat exchange plate group comprises a first heat exchange plate and a second heat exchange plate, and the distributor group comprises two distributors both installed between the first heat exchange plate and the second heat exchange plate; the inner surfaces of the first heat exchange plate and the second heat exchange plate are both provided with a first groove group and two distributor grooves respectively located at both ends of the first groove group; the groove bottom of the distributor groove is recessed inward to form a first groove group, and the first groove in the first groove group is correspondingly connected with the first groove in the first groove group; the first groove on the first heat exchange plate and the corresponding first groove on the second heat exchange plate are matched to form a first flow channel, and the inner surface is the surface of the first heat exchange plate and the second heat exchange plate facing the distributor; one side of the distributor is recessed inward to form a cavity, and the top wall and / or bottom wall of the cavity are provided with a plurality of through holes connected to the cavity, and the through holes are connected to the first groove. The efficiency of countercurrent heat exchange can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of heat exchange, and in particular to a countercurrent heat exchanger. Background Art

[0002] The PCHE heat exchanger includes a core and side plates. The core includes a plurality of hot side plates and a plurality of cold side plates that are alternately stacked and arranged in parallel. The side plates are parallel to the stacking plane and are distributed on both sides of the core. The cold side plates and the hot side plates are formed with flow channels by a chemical etching process. The hot side plates and the cold side plates are regularly stacked and welded together by brazing or diffusion welding.

[0003] PCHE heat exchangers can be divided into countercurrent heat exchange, cocurrent heat exchange and cross-current heat exchange according to the flow direction of the heat exchange fluid. Countercurrent heat exchange refers to the heat exchange of cold and hot fluids in the heat exchanger in opposite directions. In practical applications, countercurrent heat exchange is usually preferred because it has a higher average temperature difference, less heat transfer area requirements and lower heat exchange medium consumption. Figures 1 to 3 As shown, an existing counter-flow heat exchanger includes a first heat exchange plate, a second heat exchange plate and a third heat exchange plate stacked together in sequence. The front of the first heat exchange plate is arranged opposite to the front of the second heat exchange plate, and the front here is the surface of the first heat exchange plate and the second heat exchange plate facing each other. A Z-shaped first groove group is respectively provided on the front of the first heat exchange plate and the front of the second heat exchange plate. The first groove group includes a plurality of mutually parallel Z-shaped first grooves. The first groove on the first heat exchange plate is matched with the corresponding first groove on the second heat exchange plate to form a first flow channel. A plurality of linear second grooves are provided on the third heat exchange plate, and the second groove on the third heat exchange plate is matched with the back of the second heat exchange plate to form a second flow channel. The low-temperature fluid enters from one end of the first flow channel and exits from the other end of the first flow channel. During the flow of the low-temperature fluid, heat is exchanged with the high-temperature fluid flowing along the second flow channel.

[0004] The disadvantage of the existing counter-flow heat exchanger is that the first groove group includes a horizontal section 01 and two vertical sections 02 which are perpendicular to the two ends of the horizontal section 01. Since the first grooves of the vertical section 02 correspond to the first grooves of the horizontal section 01 one by one and have equal spacing, the width of the vertical section 02 (the width direction is as shown in FIG. Figure 3 The width of the horizontal segment 01 (as shown by the dashed arrow in the middle) Figure 3 This results in a larger cross-flow area in the existing countercurrent heat exchanger, while the countercurrent heat exchange area is concentrated in the horizontal section 01, resulting in a small area of ​​the countercurrent heat exchange area, which ultimately affects the countercurrent heat exchange efficiency.

[0005] In view of the above shortcomings, it is necessary to design a new countercurrent heat exchanger. Summary of the invention

[0006] Therefore, the technical problem to be solved by the present invention is that the existing counterflow heat exchanger has a large cross-flow heat exchange area, which results in a small counterflow heat exchange area, affecting the counterflow heat exchange efficiency, thereby providing a counterflow heat exchanger.

[0007] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0008] A counter-flow heat exchanger, comprising a heat exchange plate group and a distributor group, wherein the heat exchange plate group comprises a first heat exchange plate and a second heat exchange plate, and the distributor group comprises two distributors, both of which are installed between the first heat exchange plate and the second heat exchange plate; the inner surfaces of the first heat exchange plate and the second heat exchange plate are provided with a first groove group and two distributor grooves respectively located at both ends of the first groove group, and the inner surfaces are surfaces of the first heat exchange plate and the second heat exchange plate facing the distributor; the distributor groove is used to accommodate the distributor, and the groove bottom of the distributor groove is inwardly recessed to form a first groove group, and a plurality of first grooves in the first groove group are connected with a plurality of first grooves in the first groove group in a one-to-one position correspondence; the first groove on the first heat exchange plate and the corresponding first groove on the second heat exchange plate are matched to form a first flow channel;

[0009] One side surface of the distributor is recessed inward to form a cavity, and a top wall and / or a bottom wall of the cavity are provided with a plurality of through holes connected to the cavity, and the through holes are connected to the first groove.

[0010] Furthermore, the cavity gradually narrows from the side toward the inside of the dispenser.

[0011] Furthermore, the longitudinal section of the cavity is a right-angled trapezoid.

[0012] Furthermore, the lower base angle of the right trapezoid is 5 degrees to 12 degrees.

[0013] Furthermore, the two distributors are respectively an inflow distributor and an outflow distributor. In the inflow distributor, the lower base of the trapezoid corresponds to the inlet of the low-temperature fluid, and in the outflow distributor, the lower base of the trapezoid corresponds to the outlet of the low-temperature fluid.

[0014] Further, the first groove on the first heat exchange plate and the corresponding first groove extend along the same straight line, and the first groove on the second heat exchange plate and the corresponding first groove extend along the same straight line.

[0015] Further, the bottom of the first groove on the first heat exchange plate is flush with the bottom of the corresponding first groove, and the bottom of the first groove on the second heat exchange plate is flush with the bottom of the corresponding first groove.

[0016] Furthermore, a plurality of second grooves are provided on outer surfaces of the first heat exchange plate and the second heat exchange plate, and the outer surfaces are surfaces of the first heat exchange plate and the second heat exchange plate facing away from the distributor; the counterflow heat exchanger also includes another heat exchange plate group stacked with the heat exchange plate group, and the second grooves on the second heat exchange plate in one heat exchange plate group are matched with the second grooves on the first heat exchange plate in another second heat exchange plate group to form the second flow channel.

[0017] Furthermore, the projections of the first groove and the second groove on the first heat exchange plate on the plane where the first heat exchange plate is located completely overlap or partially overlap; the projections of the first groove and the second groove on the second heat exchange plate on the plane where the second heat exchange plate is located completely overlap or partially overlap.

[0018] Furthermore, the first heat exchange plate and the second heat exchange plate are mirror-image structures.

[0019] The technical solution of the present invention has the following advantages:

[0020] 1. In the countercurrent heat exchanger provided by the present invention, since the two distributor grooves are located at the two ends of the first groove group, the through holes on the top wall and / or the bottom wall of the distributor are connected to the first groove through the first groove, and the first groove on the first heat exchange plate and the corresponding first groove on the second heat exchange plate are matched to form a first flow channel. After the low-temperature liquid enters the cavity in a distributor, it is distributed into the first groove along the thickness direction of this distributor, and enters the first flow channel along the first groove, and then enters the cavity of the other distributor through the first flow channel and flows out of this cavity. This makes the first heat exchange plate and the second heat exchange plate have low-temperature fluid distributed in almost the entire length direction, and then can realize countercurrent heat exchange with high-temperature fluid in almost the entire length direction, thereby improving the countercurrent heat exchange efficiency.

[0021] 2. In the counterflow heat exchanger provided by the present invention, the cavity gradually narrows from the side of the distributor to the inside of the distributor, which can improve the distribution uniformity of the low-temperature fluid and further improve the heat exchange efficiency.

[0022] 3. The counterflow heat exchanger provided by the present invention has a lower base angle of the right-angled trapezoid of 5 to 12 degrees. Such a design can take into account the need to reduce the width of the distributor (the width direction of the distributor is parallel to the length direction of the first heat exchange plate) and provide sufficient flow area for the low-temperature fluid.

[0023] 4. In the counterflow heat exchanger provided by the present invention, the projections of the first groove and the second groove on the first heat exchange plate on the plane where the first heat exchange plate is located completely overlap or partially overlap; and the projections of the first groove and the second groove on the second heat exchange plate on the plane where the second heat exchange plate is located completely overlap or partially overlap, thereby further improving the counterflow heat exchange efficiency.

[0024] 5. In the counterflow heat exchanger provided by the present invention, a plurality of second grooves are provided on the outer surfaces of the first heat exchange plate and the second heat exchange plate, and the outer surfaces are the surfaces of the first heat exchange plate and the second heat exchange plate facing away from the distributor; the counterflow heat exchanger also includes another heat exchange plate group stacked with the heat exchange plate group, and the second grooves on the second heat exchange plate in one heat exchange plate group are matched with the second grooves on the first heat exchange plate in another second heat exchange plate group to form a second flow channel, so that there is no welding transition layer between the first flow channel and the second flow channel, thereby maximizing the heat exchange efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 It is a three-dimensional schematic diagram of an existing counter-flow heat exchanger;

[0027] Figure 2 is a top view of an existing counter-flow heat exchanger;

[0028] Figure 3 A schematic diagram of the flow passage on the cold side plate of an existing counter-flow heat exchanger;

[0029] Figure 4 is a three-dimensional schematic diagram of a counter-flow heat exchanger in an embodiment of the present invention;

[0030] Figure 5 A top view of a counter-flow heat exchanger according to an embodiment of the present invention;

[0031] Figure 6 for Figure 5 The enlarged view of A0 in the middle;

[0032] Figure 7 A side view of a counter-flow heat exchanger according to an embodiment of the present invention;

[0033] Figure 8 A bottom view of the first heat exchange plate in an embodiment of the present invention;

[0034] Fig. 9 for Figure 8 Sectional view along line BB;

[0035] Fig.10 for Fig. 9 The enlarged view of point D in the middle;

[0036] Fig.11for Figure 8 Enlarged view of point C in the middle;

[0037] Fig.12 It is a front view of the first heat exchange plate in the embodiment of the present invention;

[0038] Fig.13 for Fig.12 Enlarged view of point E in the middle;

[0039] Fig.14 is a top view of the first heat exchange plate in an embodiment of the present invention;

[0040] Fig.15 for Fig.14 The enlarged view of F in the middle;

[0041] Fig.16 is a schematic longitudinal section diagram of a dispenser in an embodiment of the present invention;

[0042] Fig.17 for Fig.16 Enlarged view of G in the middle;

[0043] Fig.18 for Fig.16 Sectional view along line HH;

[0044] Fig.19 for Fig.18 The enlarged view of point I in the middle;

[0045] Fig. 20 is a schematic diagram of a second flow channel in an embodiment of the present invention;

[0046] Fig.21 is a schematic diagram of a first flow channel and a distributor in an embodiment of the present invention;

[0047] Fig. 22 It is a three-dimensional exploded schematic diagram of the heat exchange plate group and the distributor group in an embodiment of the present invention.

[0048] Description of reference numerals:

[0049] 01, horizontal section; 02, vertical section; 1, first heat exchange plate; 2, second heat exchange plate; 3, distributor; 31, cavity; 32, through hole; 5, side plate; A, countercurrent heat exchanger; A1, first groove; A2, distributor groove; A3, first groove; A4, second groove. DETAILED DESCRIPTION

[0050] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only 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.

[0051] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0052] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0053] like Figures 1 to 22 As shown, the present invention provides a countercurrent heat exchanger A, specifically a countercurrent PCHE (Printed Circuit Heat Exchanger) heat exchanger. The countercurrent heat exchanger A includes a heat exchange plate group and a distributor group. The heat exchange plate group includes a first heat exchange plate 1 and a second heat exchange plate 2. The distributor group includes two distributors 3. Both distributors 3 are installed between the first heat exchange plate 1 and the second heat exchange plate 2. The inner surfaces of the first heat exchange plate 1 and the second heat exchange plate 2 (the inner surfaces here are the surfaces on the first heat exchange plate 1 and the second heat exchange plate 2 facing the distributor 3) are provided with a first groove group and two distributor grooves A2 respectively located at both ends of the first groove group. The distributor groove A2 is used to accommodate the distributor 3. The bottom of the distributor groove A2 is recessed inward to form a first groove group. The multiple first grooves A1 in the first groove group are connected to the multiple first grooves A3 in the first groove group in a one-to-one position correspondence. The first groove A1 on the first heat exchange plate 1 and the corresponding first groove A1 on the second heat exchange plate 2 are matched to form a first flow channel, and the first flow channel provides a flow path for the low-temperature fluid. One side of the distributor 3 is recessed inward to form a cavity 31. The top wall and / or the bottom wall of the cavity 31 are provided with a plurality of through holes 32 connected to the cavity 31. The through holes 32 are connected to the corresponding first grooves A3.

[0054] In the present invention, since the two distributor grooves A2 are located at the two ends of the first groove group, the through holes 32 on the top wall and / or bottom wall of the distributor 3 are connected to the first groove A1 through the first groove A3, and the first groove A1 on the first heat exchange plate 1 is matched with the corresponding first groove A1 on the second heat exchange plate 2 to form a first flow channel. After the low-temperature liquid enters the cavity 31 in a distributor 3, it is distributed into the first groove A3 along the thickness direction of this distributor 3, and enters the first flow channel along the first groove A3, and then enters the cavity 31 of the other distributor 3 through the first flow channel and flows out of this cavity 31. This makes the first heat exchange plate 1 and the second heat exchange plate 2 have low-temperature fluid distributed in almost the entire length direction, and then can realize countercurrent heat exchange with high-temperature fluid in almost the entire length direction, thereby improving the countercurrent heat exchange efficiency.

[0055] In this embodiment, the through holes 32 are evenly distributed on the top wall and the bottom wall of the distributor 3, so that after the cryogenic fluid enters the cavity 31, it can simultaneously enter the corresponding first groove A3 upward and downward, which is conducive to the cryogenic fluid quickly entering the first groove A1. The top wall and the bottom wall of the distributor 3 seal the corresponding opening of the first groove A3 toward the distributor 3, so that the first groove A3 is connected to the cavity 31 only through the through holes 32 on the distributor 3. In other embodiments, the through holes 32 can also be selectively distributed on the top wall and the bottom wall of the distributor 3.

[0056] In this embodiment, the cavity 31 gradually narrows from the side of the distributor 3 to the inside of the distributor 3. The longitudinal section of the distributor 3 is a right-angled trapezoid, which is not only conducive to the regular appearance of the countercurrent heat exchanger A (for example, the right-angled side of the distributor 3 is aligned with the end faces of the first heat exchange plate 1 and the second heat exchange plate 2), but also takes into account the needs of the low-temperature fluid for a larger inlet cross-section and a larger outlet cross-section. Specifically, the two distributors 3 are an inflow distributor and an outflow distributor, respectively. In the inflow distributor, the lower base of the trapezoid corresponds to the inlet of the low-temperature fluid, and in the outflow distributor, the lower base of the trapezoid corresponds to the outlet of the low-temperature fluid, which can improve the uniformity of the distribution of the low-temperature fluid and improve the heat exchange efficiency. Preferably, the lower base angle of the right-angled trapezoid is 5 to 12 degrees. Such a design can take into account reducing the width of the distributor 3 (the width direction is as shown in FIG. 2 ). Fig.21 The arrow direction in the figure is parallel to the length direction of the first heat exchange plate 1), and sufficient flow area can be provided for the low-temperature fluid.

[0057] In this embodiment, the first groove A1 on the first heat exchange plate 1 and the corresponding first groove A3 extend along the same straight line, and the first groove A1 on the second heat exchange plate 2 and the corresponding first groove A3 extend along the same straight line, so that the low-temperature fluid can flow into the first groove A1 along a straight line after entering the first groove A3. Preferably, the bottom of the first groove A1 is flush with the bottom of the corresponding first groove A3, and of course, the bottom of the first groove A1 may not be flush with the bottom of the first groove A3.

[0058] In this embodiment, the distributor groove A2 on the first heat exchange plate 1 and the distributor groove A2 on the second heat exchange plate 2 are mirror-imaged, the through holes 32 on the top wall and the bottom wall of the distributor 3 are also mirror-imaged, and the first groove group on the first heat exchange plate 1 and the first groove group on the second heat exchange plate 2 are also mirror-imaged, so that the first heat exchange plate 1 and the second heat exchange plate 2 are mirror-imaged. In addition, the outer surfaces of the first heat exchange plate 1 and the second heat exchange plate 2 (the outer surfaces here are the surfaces of the first heat exchange plate 1 and the second heat exchange plate 2 facing away from the distributor 3) are both provided with a plurality of second grooves A4, and the second grooves A4 are parallel to the first grooves A1. Of course, the first heat exchange plate 1 and the second heat exchange plate 2 do not need to be mirror-imaged.

[0059] The counter-flow heat exchanger A also includes another adjacent heat exchange plate group. For the convenience of explanation, one of the two adjacent heat exchange plate groups is defined as the first heat exchange plate group, and the other is defined as the second heat exchange plate group. The second groove A4 on the second heat exchange plate 2 in the first heat exchange plate group is matched with the second groove A4 on the first heat exchange plate 1 in the second heat exchange plate group to form a second flow channel, so that there is no welding transition layer between the first flow channel and the second flow channel, thereby maximizing the heat exchange efficiency. It should be noted that the heat exchange plate groups in a counter-flow heat exchanger A can also be three, four or even more, which is not specifically limited here and can be set according to actual needs.

[0060] Preferably, the projections of the first groove A1 and the second groove A4 on the first heat exchange plate 1 on the plane where the first heat exchange plate 1 is located completely overlap or partially overlap, and the projections of the first groove A1 and the second groove A4 on the second heat exchange plate 2 on the plane where the second heat exchange plate 2 is located completely overlap or partially overlap, so that the heat exchange efficiency can be further improved.

[0061] In this embodiment, the counterflow heat exchanger A further includes a side plate 5, which is parallel to the first heat exchange plate 1 and the second heat exchange plate 2. The first heat exchange plate 1 and the second heat exchange plate 2, the distributor 3 and the first heat exchange plate 1, and the distributor 3 and the second heat exchange plate 2 are all welded by brazing or diffusion welding.

[0062] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A countercurrent heat exchanger, characterized in that: It comprises a heat exchange plate group and a distributor group, the heat exchange plate group comprises a first heat exchange plate (1) and a second heat exchange plate (2), the distributor group comprises two distributors (3), and the two distributors (3) are both installed between the first heat exchange plate (1) and the second heat exchange plate (2); The inner surfaces of the first heat exchange plate (1) and the second heat exchange plate (2) are both provided with a first groove group and two distributor grooves (A2) respectively located at the two ends of the first groove group; the inner surface is the surface of the first heat exchange plate (1) and the second heat exchange plate (2) facing the distributor (3); the distributor groove (A2) is used to accommodate the distributor (3); the bottom of the distributor groove (A2) is recessed inward to form a first groove group; a plurality of first grooves (A1) in the first groove group are connected to a plurality of first grooves (A3) in the first groove group in a one-to-one corresponding manner; the first groove (A1) on the first heat exchange plate (1) and the corresponding first groove (A1) on the second heat exchange plate (2) are matched to form a first flow channel; One side surface of the distributor (3) is recessed inward to form a cavity (31), and a top wall and / or a bottom wall of the cavity (31) are provided with a plurality of through holes (32) connected to the cavity (31), and the through holes (32) are connected to the corresponding first grooves (A3).

2. The counterflow heat exchanger according to claim 1, characterized in that: The cavity (31) gradually narrows from the side surface toward the inside of the distributor (3).

3. The counterflow heat exchanger according to claim 2, characterized in that: The longitudinal section of the cavity (31) is a right-angled trapezoid.

4. The counterflow heat exchanger according to claim 3, characterized in that: The lower base angle of the right trapezoid is 5 degrees to 12 degrees.

5. The counterflow heat exchanger according to claim 3, characterized in that: The two distributors (3) are respectively an inflow distributor and an outflow distributor; in the inflow distributor, the lower base of the trapezoid corresponds to the inlet of the low-temperature fluid, and in the outflow distributor, the lower base of the trapezoid corresponds to the outlet of the low-temperature fluid.

6. The counterflow heat exchanger according to claim 1, characterized in that: The first groove (A1) on the first heat exchange plate (1) and the corresponding first groove (A3) extend along the same straight line, and the first groove (A1) on the second heat exchange plate (2) and the corresponding first groove (A3) extend along the same straight line.

7. The counterflow heat exchanger according to claim 1, characterized in that: The bottom of the first groove (A1) on the first heat exchange plate (1) is flush with the bottom of the corresponding first groove (A3), and the bottom of the first groove (A1) on the second heat exchange plate (2) is flush with the bottom of the corresponding first groove (A3).

8. The counterflow heat exchanger according to any one of claims 1 to 7, characterized in that: The outer surfaces of the first heat exchange plate (1) and the second heat exchange plate (2) are both provided with a plurality of second grooves (A4), and the outer surfaces are surfaces of the first heat exchange plate (1) and the second heat exchange plate (2) facing away from the distributor (3); the counterflow heat exchanger (A) further comprises another heat exchange plate group stacked with the heat exchange plate group, and the second grooves (A4) on the second heat exchange plate (2) in one heat exchange plate group are matched with the second grooves (A4) on the first heat exchange plate (1) in the other heat exchange plate group to form a second flow channel.

9. The counterflow heat exchanger according to claim 8, characterized in that The projections of the first groove (A1) and the second groove (A4) on the first heat exchange plate (1) on the plane where the first heat exchange plate (1) is located completely overlap or partially overlap; the projections of the first groove (A1) and the second groove (A4) on the second heat exchange plate (2) on the plane where the second heat exchange plate (2) is located completely overlap or partially overlap.

10. The counter-flow heat exchanger according to claim 9, characterized in that The first heat exchange plate (1) and the second heat exchange plate (2) are mirror-image structures.

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