Flow quantitative distribution device and heat exchanger

Abstract

The invention discloses a flow quantitative distribution device and a heat exchanger, the flow quantitative distribution device is assembled in a plate-fin heat exchanger, the plate-fin heat exchanger comprises a heat exchange core body formed by stacking at least two fluid channels, and every two adjacent fluid channels are separated through a partition plate; a medium inlet, a heat exchange fin and a medium outlet are sequentially arranged in each fluid channel from one end to the other end, the flow quantitative distribution device comprises distribution plates, the distribution plates are arranged at the medium inlets, and through holes with preset circulation sectional areas are formed in the distribution plates so as to control the flow of media flowing into the corresponding fluid channels along the medium inlets. The flow of fluid entering each layer of fluid channel is quantitatively adjusted through the circulation sectional area of the through hole of each distribution plate, independent adjustment of each layer of fluid channel can be met, the distribution plate can be directly arranged at the inlet of each layer of fluid channel, the sectional area of the through hole of each distribution plate can be independently adjusted according to the heat exchange design working condition, replacement is convenient, and the cost is low. The efficiency is high.

Description

Technical Field

[0001] The invention relates to the technical field of plate-fin heat exchangers, and in particular to a flow quantitative distribution device and a heat exchanger. Background Art

[0002] Plate-fin heat exchangers are widely used in various industries such as petroleum, chemical industry, and natural gas processing due to their high heat transfer efficiency, good temperature controllability, and compact structure. Plate-fin heat exchangers are usually composed of baffles, fins, seals, and guide vanes. Fins, guide vanes, and seals are placed between two adjacent baffles to form a sandwich called a channel. Such sandwiches are stacked up according to different fluid patterns and brazed into a whole to form a plate bundle. The plate bundle is the core of the plate-fin heat exchanger, and is equipped with necessary heads, pipes, supports, etc. to form a plate-fin heat exchanger.

[0003] When the heat exchange load of the heat exchanger is evenly distributed, in order to ensure the heat exchange efficiency, each fluid needs to be evenly distributed in the heat exchange channel. Due to the deviation caused by uneven structure, the conventional practice is to adjust the number and relative position of the fluid at the head inlet or add guide vanes in front of the heat exchange core in the heat exchanger. However, the structure of the guide vane is mostly a group of fins with the same deflection angle, and the amount of diversion depends on the size of the deflection angle and the density of the diversion channel.

[0004] Guide vanes can improve the uneven distribution of fluid in a certain area to a certain extent, but the following problems still exist: due to the consistency of the guide vane deflection angle, it is difficult to make quantitative distribution for each layer of fluid channels; when the fluid channel space is limited, the guide vane may be inappropriate or difficult to install, and the expected adjustment of flow distribution cannot be achieved; the guide vane has a deflection angle, which causes the fluid entering the head to generate a new velocity vector along the diversion direction, affecting the fluid flow rate entering the channel. The inlet cross-section of each channel is no longer uniform, introducing new uneven factors; the setting of the guide vane requires a certain space, which increases the ineffective heat exchange area of ​​the heat exchanger and increases the overall structure of the heat exchanger.

[0005] Therefore, how to provide a flow quantitative distribution device and a heat exchanger to at least partially solve the above-mentioned drawbacks is a technical problem that technical personnel in this field currently need to solve. Summary of the invention

[0006] The object of the present invention is to provide a flow quantitative distribution device and a heat exchanger, which can perform quantitative distribution on each layer of fluid channels.

[0007] To achieve the above-mentioned purpose, the present invention provides a flow quantitative distribution device, which is assembled inside a plate-fin heat exchanger. The plate-fin heat exchanger includes a heat exchange core composed of at least two stacked fluid channels. Two adjacent fluid channels are separated by a partition. A medium inlet, a heat exchange fin and a medium outlet are sequentially arranged in the fluid channel from one end to the other. The flow quantitative distribution device includes a distribution plate, which is arranged at the medium inlet, and the distribution plate is provided with through holes with a preset flow cross-sectional area to control the flow rate of the medium flowing along the medium inlet to the corresponding fluid channel.

[0008] Preferably, the axis of the through hole is perpendicular to the cross section of the medium inlet.

[0009] Preferably, the fluid channel includes a first fluid channel and a second fluid channel adjacent to the first fluid channel, and fixing portions are provided at both ends of the distribution plate;

[0010] The connecting member fixes the fixing portion to the seal located in the second fluid channel so that the through hole is connected to the first fluid channel; and / or,

[0011] The connecting piece fixes the fixing portion to the sealing strip located in the first fluid channel so that the through hole is connected to the second fluid channel.

[0012] Preferably, the distribution plate is embedded in the fluid channel, and two sides of the distribution plate are brazed to the corresponding partition plates.

[0013] Preferably, the cross section of the through hole perpendicular to its extension direction is circular, and / or elliptical, and / or waist-shaped, and / or strip-shaped.

[0014] Preferably, the distribution plate is specifically a seal arranged at the medium inlet, and a through hole is provided on the seal.

[0015] Preferably, there is a gap greater than or equal to 5 mm between the distribution plate and the heat exchange fins in the corresponding fluid channel, and the gap is used for mixing the media entering the fluid channel along the same distribution plate before entering the heat exchange fins.

[0016] Preferably, the fixing portion is provided with first mounting holes, and the first mounting holes are evenly arranged along the length direction of the distribution plate.

[0017] Preferably, it also includes a sealing structure, which is located between the distribution plate and the fluid channel. The sealing structure includes a second mounting hole corresponding to the first mounting hole, and an opening corresponding to the through hole. The second mounting hole is used for the passage of the connector, and the opening is connected to all the through holes of the same distribution plate.

[0018] A heat exchanger comprises the above-mentioned flow quantitative distribution device.

[0019] Compared with the above background technology, the flow quantitative distribution device provided by the present invention has at least the following technical effects:

[0020] A distribution plate is arranged at the medium inlet, and each of the distribution plates is provided with through holes with preset flow cross-sectional areas. The flow cross-sectional area of ​​the through holes of each distribution plate is used to quantitatively adjust the fluid flow entering each layer of the fluid channel, which can meet the needs of separate adjustment of each layer of the fluid channel. The distribution plate can be directly arranged at the inlet of each layer of the fluid channel without occupying additional internal space of the heat exchanger. At the same time, the distribution plate has a simple structure and is easy to process, and is suitable for a variety of distribution occasions. The cross-sectional area of ​​the through holes of the distribution plate can be individually adjusted according to the heat exchange design conditions, which is convenient for replacement, convenient and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0022] FIG1 is a schematic diagram of the structure of a flow quantitative distribution device provided in an embodiment of the present invention;

[0023] FIG2 is a schematic diagram of the structure of a distribution plate provided in an embodiment of the present invention;

[0024] FIG3 is a schematic structural diagram of a sealing structure provided by an embodiment of the present invention;

[0025] FIG4 is a schematic diagram of a structure in which a distribution plate provided by an embodiment of the present invention is embedded in a fluid channel;

[0026] FIG5 is a schematic diagram of the structure of a distribution plate provided by an embodiment of the present invention when a through hole is provided for a seal;

[0027] FIG6 is a schematic structural diagram of FIG5 from another perspective;

[0028] FIG7 is a schematic structural diagram of a flow cross section of a heat exchanger provided by an embodiment of the present invention;

[0029] FIG8 is a structural schematic diagram of fluid flow in a heat exchanger provided in an embodiment of the present invention.

[0030] in:

[0031] 100- partition, 110- first heat exchange fin, 120- second heat exchange fin, 130- seal;

[0032] 200-distribution plate, 210-through hole, 220-gap, 230-first mounting hole;

[0033] 300-connector, 310-washer;

[0034] 400 - sealing structure, 410 - second mounting hole, 420 - opening. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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.

[0036] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0037] In the description of the present invention, it should be understood that the terms "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the position or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as a limitation of the present invention.

[0038] The object of the present invention is to provide a flow quantitative distribution device and a heat exchanger, which can perform quantitative distribution on each layer of fluid channels.

[0039] Please refer to Figures 1, 2 and 3. To achieve the above-mentioned purpose, the present invention provides a flow quantitative distribution device, which is assembled inside a plate-fin heat exchanger. The plate-fin heat exchanger includes a heat exchange core composed of at least two stacked fluid channels. Two adjacent fluid channels are separated by a partition 100. A medium inlet, a heat exchange fin and a medium outlet are sequentially arranged in the fluid channel from one end to the other. The flow quantitative distribution device includes a distribution plate 200, which is arranged at the medium inlet, and the distribution plate 200 is provided with through holes 210 with a preset flow cross-sectional area to control the flow of the medium flowing along the medium inlet to the corresponding fluid channel.

[0040] A distribution plate 200 is provided at the medium inlet, and a through hole 210 with a preset flow cross-sectional area is provided on the distribution plate 200. The flow cross-sectional area of ​​the through hole 210 of each distribution plate 200 is used to quantitatively adjust the fluid flow entering each layer of the fluid channel, which can meet the needs of separate adjustment of each layer of the fluid channel. The distribution plate 200 can be directly arranged at the entrance of each layer of the fluid channel without occupying additional internal space of the heat exchanger. At the same time, the distribution plate 200 has a simple structure and is easy to process, and is suitable for a variety of distribution occasions. The cross-sectional area of ​​the through hole 210 of the distribution plate 200 can be individually adjusted according to the heat exchange design conditions, which is convenient for replacement, convenient and efficient.

[0041] Among them, the axis of the through hole 210 is perpendicular to the cross-section of the medium inlet, that is, the extension direction of the through hole 210 is perpendicular to the cross-section of the medium inlet. After the fluid passes through the through hole 210, the consistency of the velocity vector of the fluid at the medium inlet cross section of each fluid channel can be guaranteed, which can avoid the fluid flow rate entering the channel from being no longer uniform at the medium inlet cross section of each fluid channel, thereby avoiding the introduction of new uneven factors.

[0042] It can be understood that the preset flow cross-sectional area of ​​the through hole 210 is the sum of the projected areas of the through holes 210 on the same distribution plate 200 in the axial direction thereof. The size of the preset flow cross-sectional area can be adjusted by the size of the through holes 210 or by the number of the through holes 210. For example, the through holes 210 are evenly arranged in the middle of the distribution plate 200 along the length direction of the distribution plate 200. The cross-section of the through hole 210 perpendicular to its own extension direction is circular, and / or elliptical, and / or waist-shaped, and / or strip-shaped, etc. The size and number of the through holes 210 on each distribution plate 200 can be used to quantitatively adjust the fluid flow rate entering each layer of the channel.

[0043] In this embodiment, the fluid channel includes a first fluid channel and a second fluid channel adjacent to the first fluid channel. A first heat exchange fin 110 is installed in the first fluid channel, and a second heat exchange fin 120 is installed in the second fluid channel. Fixed parts are provided at both ends of the distribution plate 200. Taking the overall shape of the fluid channel as a cube as an example, the fluid channel includes two opposite long sides and two opposite short sides. When the medium inlet and the medium outlet are located at the short side position, the long side position must be sealed by the seal 130; when the medium inlet and the medium outlet are located at the long side position, the short side position must be sealed by the seal 130.

[0044] The connector 300 fixes the fixing portion to the seals 130 on the two second fluid channels adjacent to the first fluid channel so that the through hole 210 is connected to the first fluid channel; and / or, the connector 300 fixes the fixing portion to the seals 130 on the two first fluid channels adjacent to the second fluid channel so that the through hole 210 is connected to the second fluid channel. The distribution plate 200 can be directly arranged at the entrance of each layer of fluid channels without occupying additional internal space of the fluid channels.

[0045] Among them, the fixing part is provided with a first mounting hole 230, and the first mounting hole 230 is evenly arranged along the length direction of the distribution plate 200. In order to ensure that the fluid does not leak after passing through the distribution plate 200, a sealing structure 400 is also provided. The sealing structure 400 can adopt a sealing gasket. The sealing structure 400 is located between the distribution plate 200 and the fluid channel. The sealing structure 400 includes a second mounting hole 410 corresponding to the first mounting hole 230, and an opening 420 corresponding to the through hole 210. The second mounting hole 410 is used for the penetration of the connecting piece 300, and the opening 420 is connected to all the through holes 210 on the same distribution plate 200.

[0046] It should be noted that the first mounting hole 230 and the second mounting hole 410 can be set as bolt holes of the same size. The connecting member 300 adopts a bolt, which is passed through the first mounting hole 230 and the second mounting hole 410 and screwed into the corresponding seal 130. A gasket 310 is sleeved on the bolt so that the distribution plate 200 presses the sealing structure 400 to the edge of the partition 100. The opening 420 on the sealing structure 400 can adopt a strip hole, and the cross-sectional size of the strip hole is the same or similar to the cross-sectional size of the medium inlet of the fluid channel. The through hole 210 and the opening 420 correspond to each other, so that the fluid can enter along the through hole 210 and then smoothly enter the fluid channel for heat exchange.

[0047] Please refer to Figures 4 and 5. In some embodiments, the distribution plate 200 can be embedded in the fluid channel, and the two sides of the distribution plate 200 are brazed with the corresponding partitions 100. Specifically, the distribution plate 200 is set between the two partitions 100, and the distribution plate 200 is located at the edge of the partition 100. The two sides of the distribution plate 200 are tightly fitted with the partition 100 through brazing, so that the fluid can only flow into the fluid channel along the through holes 210 on the distribution plate 200.

[0048] Please refer to Figure 6. In other embodiments, the distribution plate 200 is specifically a seal 130 arranged at the medium inlet, and a through hole 210 is provided on the seal 130. Specifically, the seal 130 is provided at the medium inlet. By opening the through hole 210 on the seal 130, the purpose of restricting the flow of the fluid can also be achieved, thereby realizing the multifunctional utilization of the existing structure, and the process operation is simple, which is conducive to the reduction of the overall structure of the heat exchanger and the reduction of the weight of the heat exchanger.

[0049] Among them, there is a gap 220 greater than or equal to 5 mm between the distribution plate 200 and the heat exchange fins in the corresponding fluid channel. When the distribution plate 200 is fixed by bolts, the cross-sectional size of the opening 420 on the sealing structure 400 is the same or similar to the cross-sectional size of the fluid channel entrance, so that the flow area after the fluid passes through the through hole 210 of the distribution plate 200 is a whole. When the distribution plate 200 is brazed, the above-mentioned sealing structure 400 is not used, and the flow area between the distribution plate 200 and the heat exchange fins is also a whole. The gap 220 is used for mixing the medium entering the fluid channel along the same distribution plate 200 before entering the heat exchange fins. Uniform mixing of the fluid can ensure the uniformity of the flow rate of the entire fluid channel cross section.

[0050] Please refer to Figure 7. In the heat exchange condition, there is a situation where the flow section on one side is non-square (for example, circular). According to the existing plate-fin manufacturing process, the heat exchange unit is mostly a combination of several groups of square heat exchangers, and then the required flow section A is obtained by blocking the flow section.

[0051] Please refer to Figure 8. Taking cross-flow heat exchange as an example, the fluid on the X side flows vertically through the cross section of the heat exchanger, and the fluid on the Y side forms a cross flow from top to bottom or from bottom to top to exchange heat with it.

[0052] When the fluid flow rate on the X side and the temperature uniformity of the airflow at the inlet section are good, the Y side that exchanges heat with it has different chord lengths corresponding to the heat exchange area at the centerline position and the edge position (different heat exchange area per unit width), which results in different required heat exchange loads. When the fluid flow rates in each channel on the Y side are the same, the heat exchange in the short chord area will inevitably be greater than that in the center long chord area. Especially for the heat exchanger module B located at the edge of the wind tunnel, the deviation of the left and right chord lengths is more obvious, which will inevitably lead to an increase in the temperature difference on the outlet section of this heat exchange module.

[0053] This balance of heat exchange load can be achieved by adjusting the fluid flow in the channels at different positions on the Y side during design.

[0054] The principle of adjusting the flow distribution in different channels by the distribution plate 200 is:

[0055] When the fin structures in each channel are the same and the flow rates are the same, the pressure loss of the fluid flowing through each channel will be the same.

[0056] The following process takes the flow rate into each layer of channels as an example by adjusting the opening rate, and applies different local resistance losses at the entrance of each channel. The smaller the opening rate, the greater the pressure loss in the opening area. In order to balance the pressure loss of the entire channel, the flow rate in the corresponding channel will be smaller, thereby achieving the purpose of flow regulation.

[0057] For the perforated distribution plate 200, the expression of the power source term is:

[0058] (1);

[0059] In the formula, is the pressure of the distribution plate 200, in Pa. The sum of the pressure drop of the distribution plate 200 of each channel and the pressure drop of the core is the total pressure of the channel, and the total pressure is designed to be consistent; is the thickness of the orifice plate, in meters (m); ρ is the fluid density, in kg / m 3 ; u is the average flow velocity of the flow section, the unit is m / s; The empirical formula is:

[0060] (2);

[0061] In the formula, is the porosity of the distribution plate 200; C is the empirical coefficient, which is related to the Reynolds number and the plate thickness-aperture ratio.

[0062] The number of openings N of the distribution plate 200 is:

[0063] (3);

[0064] is the length of the orifice plate, in meters (m); D is the width of the orifice plate, in meters (m); is the diameter of the opening, in meters (m).

[0065] Based on the calculation results of the above formula, according to the ratio of the chord length of each channel of the distribution plate 200 to the total length, the number and size of the through holes 210 opened in the distribution plate 200 are adjusted. Taking the uniform size of the through holes 210 as an example, the ratio of the number of through holes 210 opened in each fluid channel to the total number of through holes 210 opened is close to the ratio of the corresponding channel chord length. Then, the corresponding calculation model is established through CFD (computational fluid dynamics) software to examine the consistency between the adjustment effect of the opening and the design value, and the design scheme is appropriately adjusted based on the simulation results.

[0066] A heat exchanger includes the above-mentioned flow quantitative distribution device, which also has the beneficial effects of the above-mentioned flow quantitative distribution device, and will not be described in detail here.

[0067] It should be noted that, in this specification, relational terms such as first and second are merely used to distinguish one entity from other entities, but do not necessarily require or imply any actual relationship or order between these entities.

[0068] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0069] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core ideas of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the present invention.

Claims

1. A flow quantitative distribution device, installed inside a plate-fin heat exchanger, wherein the plate-fin heat exchanger comprises a heat exchange core composed of at least two stacked fluid channels, two adjacent fluid channels are separated by a partition (100), and a medium inlet, a heat exchange fin and a medium outlet are sequentially arranged in the fluid channel from one end to the other end, characterized in that: The flow quantitative distribution device comprises a distribution plate (200), the distribution plate (200) being arranged at the medium inlet, and the distribution plate (200) being provided with through holes (210) with a preset flow cross-sectional area, so as to control the flow of the medium flowing along the medium inlet to the corresponding fluid channel.

2. The flow quantitative distribution device according to claim 1, characterized in that: The axis of the through hole (210) is perpendicular to the cross section of the medium inlet.

3. The flow quantitative distribution device according to claim 1 or 2, characterized in that: The fluid channel comprises a first fluid channel and a second fluid channel adjacent to the first fluid channel, and fixing parts are provided at both ends of the distribution plate (200); The connecting member (300) fixes the fixing portion to the seal (130) located in the second fluid channel, so that the through hole (210) is connected to the first fluid channel; and / or, The connecting member (300) fixes the fixing portion to the seal (130) located in the first fluid channel, so that the through hole (210) is connected to the second fluid channel.

4. The flow quantitative distribution device according to claim 1 or 2, characterized in that: The distribution plate (200) is embedded in the fluid channel, and two sides of the distribution plate (200) are brazed to the corresponding partition plates (100).

5. The flow quantitative distribution device according to claim 1 or 2, characterized in that: The cross section of the through hole (210) perpendicular to its own extension direction is circular, and / or elliptical, and / or waist-shaped, and / or strip-shaped.

6. The flow quantitative distribution device according to claim 1 or 2, characterized in that: The distribution plate (200) is specifically a seal (130) arranged at the medium inlet, and the seal (130) is provided with the through hole (210).

7. The flow quantitative distribution device according to claim 1 or 2, characterized in that: There is a gap (220) of greater than or equal to 5 mm between the distribution plate (200) and the heat exchange fin in the corresponding fluid channel, and the gap (220) is used for mixing the medium entering the fluid channel along the same distribution plate (200) before entering the heat exchange fin.

8. The flow quantitative distribution device according to claim 3, characterized in that: The fixing portion is provided with first mounting holes (230), and the first mounting holes (230) are evenly arranged along the length direction of the distribution plate (200).

9. The flow quantitative distribution device according to claim 8, characterized in that: The invention also comprises a sealing structure (400), wherein the sealing structure (400) is located between the distribution plate (200) and the fluid channel, and the sealing structure (400) comprises a second mounting hole (410) corresponding to the first mounting hole (230), and an opening (420) corresponding to the through hole (210), wherein the second mounting hole (410) is used for the connection member (300) to pass through, and the opening (420) is connected to all the through holes (210) of the same distribution plate (200).

10. A heat exchanger, characterized in that: It comprises a flow quantitative distribution device as described in any one of claims 1 to 9 above.

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