A plate heat exchanger with a multi-layer structure having through holes

Abstract

The present invention provides a plate heat exchanger with a multi-layer structure having through holes, wherein the first layer, the second layer, the third layer and the fourth layer are arranged in sequence from top to bottom, the first layer includes a cold fluid inlet and a cold fluid outlet arranged on the front, the second layer includes an inlet header, an outlet header, an inlet branch pipe, an outlet branch pipe, an inlet flow channel and an outlet flow channel arranged on the front, and the fourth layer is a hot fluid pipeline in thermal contact with the third layer; it is characterized in that a plurality of through holes penetrating the second layer are arranged in each inlet and outlet branch pipe, and the aperture of each through hole gradually increases along the flow direction of the fluid in the inlet header. The present invention aims to provide a plate heat exchanger, which makes the fluid distribution along the flow direction more uniform, and avoids the problems of uneven heat exchange and excessively high or low local temperatures caused by uneven fluid distribution.

Description

Technical Field

[0001] The invention relates to a heat exchanger technology, in particular to a plate heat exchanger. Background Art

[0002] A heat exchanger is a device that exchanges heat between hot and cold fluids, also known as a heat exchanger. Heat exchangers are widely used in many fields. In fields such as electronics, petrochemicals, communications, aerospace, etc., due to their special working scenes, there are special requirements for the size and weight of the heat exchanger, and their heat exchange capacity is required to be stronger. In 1981, some scholars proposed the use of microchannels for heat dissipation, which can not only reduce the volume of the heat exchanger but also greatly improve its heat exchange capacity by utilizing the higher specific surface area of ​​the microchannel. However, although its heat exchange capacity is strong, its overall pressure loss is also high due to the small hydraulic diameter of the microchannel.

[0003] The plate heat exchanger is the heat exchanger with the highest heat exchange efficiency among all types of heat exchangers. It has the advantages of small space occupation and easy installation and disassembly. It is composed of stamped concave and convex stainless steel plates. The concave and convex patterns between two adjacent plates are 180 degrees relative to each other. Therefore, the concave and convex ridges between the two plates of the plate heat exchanger form staggered contact points. After the contact points are combined by vacuum welding, the high-pressure resistant staggered flow structure of the plate heat exchanger is formed. These staggered flow structures make the cold and hot liquids in the plate heat exchanger produce strong turbulence to achieve high heat exchange effect.

[0004] Flat tubes have been widely used in automotive air conditioning units and residential or commercial air conditioning heat exchangers in recent years. This type of flat tube has multiple small channels inside, and when in use, the heat exchange liquid flows through the multiple channels inside the flat tube. Because the flat tube has a large heat exchange area, it can greatly improve the heat exchange effect.

[0005] Flat plate heat exchangers are widely used in industries such as chemical industry, petroleum, refrigeration, nuclear energy and power. Due to the global energy crisis, in order to reduce energy consumption, the demand for heat exchangers in industrial production is increasing, and the quality requirements for heat exchangers are also getting higher and higher. In recent decades, although compact heat exchangers (plate, plate-fin, press-welded plate heat exchangers, etc.), heat pipe heat exchangers, direct contact heat exchangers, etc. have developed rapidly, shell and tube heat exchangers still dominate production and usage due to their high reliability and wide adaptability. According to relevant statistics, the use of shell and tube heat exchangers in industrial devices still accounts for about 70% of all heat exchangers.

[0006] After the flat plate heat exchanger is scaled, conventional steam cleaning and backwashing are used to clean the heat exchanger. Production practice has shown that the effect is not very good. The only way is to disassemble the heat exchanger head and use physical cleaning. However, this method of cleaning is complicated and time-consuming, and requires a large investment in manpower and material resources, which brings great difficulties to continuous industrial production.

[0007] In refrigeration equipment, various refrigeration heat exchangers are indispensable key equipment and important equipment that can improve its performance. In small refrigeration systems, people have put forward higher and higher requirements on the quality, volume and heat exchange performance of heat exchangers. In ordinary fin-tube heat exchangers, there is a large gap thermal resistance between the fins and the pipes, which weakens the heat exchange effect, and the size and volume are large, which is not conducive to the miniaturization and lightweight of the system. However, in the partition-type micro heat exchanger, the heat exchange fins are connected together by brazing, which improves the heat exchange efficiency. In addition, the partition-type micro heat exchanger has outstanding advantages such as small size and high heat transfer coefficient, and its application in small refrigeration systems is becoming more and more common.

[0008] In the indirect liquid cooling solution, a heat exchanger is used for heat exchange. A heat exchanger is a metal heat exchange device with a flow channel structure, usually made of copper or aluminum. The heat exchange liquid is directly in contact with the bottom surface of the heat exchanger base plate, and the heat is transferred to the heat exchanger, and then the heat exchanger and the internal cooling liquid are convectively exchanged to take away the heat. The entire liquid cooling system uses a pump to provide power for the circulation of the working fluid. Compared with the air cooling system, the liquid cooling system has a more compact structure. Moreover, the cooling liquids used are mostly deionized water compatible with the heat exchanger material, a specified percentage of ethylene glycol-deionized water, nano liquids and other media. They have higher specific heat capacity and thermal conductivity than air, and are better than air cooling in heat dissipation effect. In addition, compared with the air cooling system, the noise level of the indirect liquid cooling system is significantly reduced.

[0009] In recent years, in order to meet the needs of heat exchange, research on indirect liquid cooling systems has been carried out, involving many aspects such as heat exchanger structure, cooling liquid selection, and pipeline layout. It is found that the heat exchanger structure has a particularly significant impact on the heat exchange and power consumption of the liquid cooling system. The heat exchanger can generally be divided into three parts: the base plate, the flow channel, and the cover plate. There is no unified standard for the cover plate and the hose connector. Different manufacturers have different structural forms. The base plate and the flow channel can be configured in various ways according to the equipment and thermal design power consumption, which is also the main factor affecting the heat dissipation performance of the heat exchanger.

[0010] Fins: Adding fins can help increase the heat exchange area and enhance the disturbance of the flow field. Intensifying heat exchange by adding fins has been widely used in heat exchangers. However, this design cannot only consider the heat dissipation effect, but also should be based on the economic efficiency of the system to avoid the situation where the pressure drop increases sharply after adding fins while the heat dissipation improvement effect is minimal. Considering that the temperature of the cooling liquid is relatively lower at the inlet, no fins are arranged in the central high flow rate area in order to improve the pressure drop of the heat exchanger, and cylindrical fins are arranged in the peripheral low flow rate area to enhance the disturbance and increase the heat exchange area, thereby compensating for the loss of heat dissipation capacity caused by the increase in the temperature of the cooling liquid.

[0011] Flow guide structure: In order to avoid the occurrence of flow dead zones during the convective heat exchange between the cooling liquid and the heat exchanger, some long straight baffle plates are arranged in the heat exchanger as flow guide structures, drawing on the baffle plates widely used in heat exchangers. The flow direction of the cooling liquid is changed in certain areas of the flow field, in order to improve the flow field distribution of the cooling liquid in the heat exchanger.

[0012] However, when designing a plate heat exchanger, the processing technology must also be considered. Sometimes it is subject to many restrictions, such as complex flow channel structure, which makes it difficult to process; when the total heat exchange area remains unchanged, the thicker the fins, the larger the spacing, the smaller the heat exchange area, and the lower the heat dissipation capacity of the cold plate. In order to increase the heat exchange area, the fin thickness is designed to be too small and the arrangement is dense, which is difficult to process and increases the flow resistance, which is not conducive to the flow distribution of the system. This type of optimization design achieves the purpose of strengthening heat exchange by changing the flow channel form and reducing the fin volume. Since the heat dissipation area of ​​the flow channel is limited, it is extremely important to further increase the heat exchange area and improve the temperature uniformity to enhance its heat dissipation performance.

[0013] In view of the above defects, the present invention improves the current heat exchanger and provides a new plate heat exchanger. The dormitory heat exchanger adopts porous materials and conducts detailed research and optimization on the porous structure, which can ensure the uniform distribution of fluid, improve heat exchange efficiency, further increase the heat exchange area and improve temperature uniformity. In addition, porous materials can be 3D printed, making it simple to process and easy to operate, and can realize structures that are difficult to achieve normally. The hot fluid channel is improved to reduce its flow resistance and improve heat exchange efficiency. Summary of the invention

[0014] The present invention aims to provide a plate heat exchanger with a new structure. The porous structure is adopted, and the porous structure is studied and optimized in detail to ensure the uniform distribution of the fluid, improve the heat exchange efficiency, further increase the heat exchange area and improve the temperature uniformity. The hot fluid channel is improved to reduce the flow resistance and improve the heat exchange efficiency. The hot fluid channel is improved to reduce the flow resistance and improve the heat exchange efficiency.

[0015] In order to achieve the above object, the technical solution of the present invention is as follows:

[0016] A plate heat exchanger with a multi-layer structure having through holes, wherein a first layer, a second layer, a third layer and a fourth layer are arranged in sequence from top to bottom, the first layer includes a cold fluid inlet and a cold fluid outlet arranged on the front side, the second layer includes an inlet header, an outlet header, an inlet branch pipe, an outlet branch pipe, an inlet flow channel and an outlet flow channel arranged on the front side, and the fourth layer is a hot fluid pipeline in thermal contact with the third layer; it is characterized in that a plurality of through holes penetrating the second layer are arranged in each inlet and outlet branch pipe, and the aperture of each through hole gradually increases along the flow direction of the fluid in the inlet header.

[0017] Preferably, along the flow direction of the fluid in the inlet header, the amplitude of the gradual increase of the aperture of each through hole becomes larger and larger.

[0018] Preferably, the upstream of the inlet manifold and the downstream of the outlet manifold are respectively connected to the cold fluid inlet and the cold fluid outlet of the first layer, the inlet manifold and the outlet manifold are respectively connected to the inlet branch pipe and the outlet branch pipe, the front side of the second layer includes a plurality of bent plate structures, one side of the plate structure forms an inlet branch pipe, and the other side forms an outlet branch pipe, the inlet branch pipe and the outlet branch pipe are not directly connected; through holes that penetrate the second layer are arranged in the inlet branch pipe and the outlet branch pipe, thereby forming an inlet flow channel and an outlet flow channel.

[0019] Preferably, the third layer includes a porous material located on the front side, and the porous material is connected to the inlet flow channel and the outlet flow channel; the porous material is printed using 3D printing technology, so that the porous material has a variable pore structure, and the pore diameter at the inlet of the inlet flow channel fluid is larger than the pore diameter at the outlet of the outlet flow channel fluid.

[0020] Preferably, along the flow direction of the fluid in the inlet header, the pore distribution density of the porous material gradually increases.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] 1) The present invention aims to provide a plate heat exchanger that makes the fluid distribution more uniform along the flow direction, thereby avoiding the problems of uneven heat exchange and excessively high or low local temperatures caused by uneven fluid distribution.

[0023] 2) The present invention adopts a capillary structure for the plate heat exchanger and uses 3D printing technology for the capillary structure to realize a variable pore structure, where the pore diameter at the fluid inlet is larger than the pore diameter at the fluid outlet, thereby improving work efficiency and making the pore diameter change more accurate.

[0024] 3) The present invention uses 3D printing technology for the capillary structure to achieve a variable pore density that is gradually distributed along the flow of the fluid, improves the processing technology, and can accurately achieve regular changes by computer. Compared with the existing preparation process, the processing results are more accurate, and the accurate structural amplitude changes are achieved through computer programs, which greatly improves the processing accuracy and thus improves the heat exchange efficiency.

[0025] 4) In the present invention, the aperture at the fluid inlet is larger than the aperture at the fluid outlet, and the convective heat transfer capacity of the cold fluid at different apertures is different, thereby improving the overall temperature uniformity and convective heat transfer capacity of the cold plate.

[0026] 5) The present invention distributes the pore density gradually along the flow of the fluid, so that the fluid is evenly distributed on the entire heat exchange surface, thereby improving the overall temperature uniformity and convection heat transfer capacity of the cold plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the overall structure of the heat exchanger of the present invention;

[0028] Figure 2 It is a schematic diagram of the disassembled structure of the heat exchanger of the present invention;

[0029] Figure 3 It is a second-layer structural diagram of the heat exchanger of the present invention;

[0030] Figure 4 It is a schematic diagram of the flow of cold fluid in the heat exchanger of the present invention;

[0031] Figure 5 is a schematic diagram of a preferred embodiment of the fourth layer fin structure;

[0032] Figure 6 It is a schematic diagram of another preferred embodiment of the fourth layer fin structure. DETAILED DESCRIPTION

[0033] The following is a detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings. The front side in the description refers to the side facing upward during installation.

[0034] Figure 1-6 A plate heat exchanger is disclosed. Figure 1 As shown, a porous material plate heat exchanger comprises a first layer 1, a second layer 2, a third layer 3 and a fourth layer 4 arranged in sequence from top to bottom. The first layer is provided with a cold fluid inlet and outlet at the top. The fourth layer is provided with a hot fluid inlet and outlet.

[0035] Preferably, the fourth layer hot fluid inlet is arranged at the center of the back side of the fourth layer, and the hot fluid outlet is arranged on both sides of the fourth layer, such as Figure 1 As shown in Figure 1. The hot fluid flows in from the center and out from the sides.

[0036] Preferably, the hot fluid flows in from one side of the fourth layer and flows out from the other side of the fourth layer. Figure 1 Flow in from the left and out from the right.

[0037] like Figure 2 As shown, the first layer 1 includes a cold fluid inlet 11 and a cold fluid outlet 12 arranged at both ends of the front side of the third layer, and the second layer 2 includes an inlet header 21, an outlet header 22, an inlet branch pipe 23, an outlet branch pipe 24, an inlet flow channel 25 and an outlet flow channel 26 arranged on the front side of the second layer, wherein the upstream of the inlet header 21 and the downstream of the outlet header 22 are respectively connected to the fluid inlet 11 and the fluid outlet 12 of the first layer, the inlet header 21 and the outlet header 22 are respectively connected to the inlet branch pipe 23 and the outlet branch pipe 24, and the second layer 2 includes a plurality of bent plate-like structures, wherein the plate-like structures are An inlet branch pipe 23 is formed on one side, and an outlet branch pipe 24 is formed on the other side, and the inlet branch pipe 23 and the outlet branch pipe 24 are not directly connected; through holes penetrating the second layer are set in the inlet branch pipe 23 and the outlet branch pipe 24, so as to form an inlet flow channel 25 and an outlet flow channel 26; the third layer 3 includes a porous material 31 located on the front side, and the porous material 31 is connected to the inlet flow channel 25 and the outlet flow channel 26; the porous material 31 adopts 3D printing technology, so that the porous material 31 is a variable pore structure, and the pore size at the inlet flow channel fluid inlet is larger than the pore size at the outlet flow channel fluid outlet. The fourth layer is a hot fluid pipeline in thermal contact with the third layer. The hot fluid flows through the fourth layer and transfers heat to the cold fluid of the third layer.

[0038] The present invention adopts porous materials and manufactures the porous materials using 3D printing technology. The third layer forms a more compact microchannel by adding a porous material structure at the bottom. Compared with the fin channel, the processing difficulty is reduced, the flow space of the cold fluid and the convection heat exchange area are increased, and the temperature uniformity of the bottom surface can be improved by changing the pore size at the inlet and outlet of the porous material.

[0039] Compared with traditional manufacturing technology, the manufacture of porous materials through 3D printing technology can accurately realize the size of the pore size, improve work efficiency, and make the pore size change more accurate.

[0040] The present invention improves the overall temperature uniformity and convective heat transfer capacity of the cold plate by making the pore size at the inlet of the porous medium fluid larger than the pore size at the outlet of the fluid, and making the convective heat transfer capacity of the cold fluid different at different pore sizes. For the flow heat transfer process under uniform pore size, the temperature of the fluid at the inlet is relatively low, and the temperature difference with the cold plate is relatively large, so the heat transfer process is relatively intense. When the fluid flows to the outlet, the temperature of the fluid rises to a certain extent due to the continuous absorption of heat from the heat source during the previous flow process, resulting in a decrease in the heat transfer temperature difference between the fluid and the cold plate at the outlet, and the heat transfer capacity is greatly reduced compared to the inlet. This will cause the holes at the inlet to carry more heat away by the fluid, while the holes at the outlet to carry less heat away, resulting in poor temperature uniformity of the bottom plate. For the flow heat transfer process under variable pore size, the larger pore size at the inlet increases the thermal resistance of thermal conductivity, and the heat absorbed by the fluid here is reduced, which enhances the ability of the fluid at the outlet to carry heat. At the same time, the smaller pore size at the outlet can enhance disturbance and heat transfer. However, the inlet and outlet apertures cannot differ too much. The preferred inlet and outlet aperture ratio is between 1.5 and 2.5. Otherwise, the heat exchange process at the outlet will be too intense, which will also lead to poor temperature uniformity of the bottom plate.

[0041] The present invention adopts 3D printing technology to manufacture the porous medium. First, a three-dimensional model of the porous medium is established in the Spaceclaim software, and the model is imported into the print preparation software PreForm, in which the direction, support material, component material and wall thickness of the model are determined. The porous medium adopts AlSi10Mg aluminum alloy material. After the above preparation work is completed, the Formlabs 3D printer is operated for printing. After printing, the building platform is directly inserted into Form Wash to automatically clean the model efficiently and evenly. After cleaning, the porous medium is removed from the printing surface with the help of rapid peeling technology. The support structure can be removed in just a few seconds. Finally, the porous medium is transferred to Form Cure for curing to maximize material performance and ensure dimensional accuracy.

[0042] Preferably, the pore size of the porous material gradually increases along the flow direction of the fluid in the inlet manifold 21. Through the above distribution, the capillary force gradually increases along the direction away from the inlet manifold inlet, and the flow resistance becomes smaller and smaller, making it more difficult for the fluid with large resistance to flow in relative to the fluid with small resistance, thereby making the fluid distribution along the flow direction more uniform, avoiding the problem of uneven heat exchange and excessively high or low local temperature caused by uneven fluid distribution.

[0043] Preferably, the aperture of the porous material gradually increases along the flow direction of the fluid in the inlet manifold 22. The above-mentioned change amplitude design is also a structure optimized through a large number of experiments and numerical simulations, which can further achieve the technical effect of uniform fluid distribution and better meet the needs of the invention of this application.

[0044] Preferably, the pore size of the porous material changes according to the following rule:

[0045] The total length of the inlet header is L, and the diameter of the downstream aperture of the inlet header is D 末 , the aperture D at a distance l from the inlet of the inlet header is as follows: D 2 =f×(D 末 ) 2 +g×(D 末 ) 2 × (l / L) e , where e, f, and g are coefficients that meet the following requirements:

[0046] 1.083 <e<1.104,0.995<f+g<1.011,0.499<f<0.625。

[0047] Preferably, as l / L increases, e gradually increases.

[0048] As a preference, 0.095 <e<1.100,f+g =1,0.565<f<0.578。

[0049] Through the above-mentioned settings, the fluid distribution is made more uniform. The above-mentioned optimization formula is obtained through a large number of experiments and numerical simulations, which can optimize the technical effect of achieving uniform fluid distribution and better meet the needs of the invention of this application.

[0050] Preferably, the pore distribution density of the porous material gradually increases along the flow direction of the fluid in the inlet manifold 21. Through the above distribution, the capillary force gradually increases along the direction away from the inlet of the inlet manifold, and the flow resistance becomes smaller and smaller, making it more difficult for the fluid with large resistance to flow in relative to the fluid with small resistance, thereby making the fluid distribution along the flow direction more uniform, avoiding the problem of uneven heat exchange and excessively high or low local temperature caused by uneven fluid distribution.

[0051] Preferably, the pore distribution density of the porous material gradually increases along the flow direction of the fluid in the inlet manifold 22. The above-mentioned change range design is also a structure optimized through a large number of experiments and numerical simulations, which can further achieve the technical effect of uniform fluid distribution and better meet the needs of the invention of this application.

[0052] Preferably, the pore distribution density of the porous material changes according to the following rule:

[0053] The total length of the inlet header is L, and the density at the most downstream of the inlet header is M 入 The density M at a distance l from the inlet manifold inlet is as follows: M = b × M 入 +c×M 入× (l / L) a , where a, b, c are coefficients that meet the following requirements:

[0054] 1.082 <a<1.105,0.994<b+c<1.012,0.498<b<0.629。

[0055] Preferably, as l / L increases, a gradually increases.

[0056] As a preference, 0.095 <a<1.100,b+c=1,0.565<b<0.578。

[0057] Through the above-mentioned settings, the fluid distribution is made more uniform. The above-mentioned optimization formula is obtained through a large number of experiments and numerical simulations, which can optimize the technical effect of achieving uniform fluid distribution and better meet the needs of the invention of this application.

[0058] Preferably, a plurality of through holes penetrating the second layer are provided in each inlet and outlet branch pipe. The distribution density of the through holes gradually increases along the flow direction of the fluid in the inlet manifold 21. Through the above distribution, along the direction from the inlet of the inlet manifold, as the flow area changes, the flow resistance becomes smaller and smaller, making it more difficult for the fluid with large resistance to flow in relative to the fluid with small resistance, thereby making the fluid distribution along the flow direction more uniform, avoiding the problem of uneven heat exchange and excessively high or low local temperature caused by uneven fluid distribution.

[0059] Preferably, the distribution density of the through holes gradually increases along the flow direction of the fluid in the inlet manifold 22. The above-mentioned change range design is also a structure optimized through a large number of experiments and numerical simulations, which can further achieve the technical effect of uniform fluid distribution and better meet the needs of the invention of this application.

[0060] Preferably, a plurality of through holes penetrating the second layer are provided in each inlet and outlet branch pipe. The aperture of each through hole gradually increases along the flow direction of the fluid in the inlet manifold 21. Through the above distribution, the flow area gradually increases along the direction away from the inlet of the inlet manifold. As the flow area changes, the flow resistance becomes smaller and smaller, making it more difficult for the fluid with large resistance to flow in relative to the fluid with small resistance, thereby making the fluid distribution along the flow direction more uniform, avoiding the problem of uneven heat exchange and excessively high or low local temperature caused by uneven fluid distribution.

[0061] Preferably, the amplitude of the gradual increase of the aperture of each through hole becomes larger along the flow direction of the fluid in the inlet manifold 22. The above-mentioned amplitude change design is also a structure optimized through a large number of experiments and numerical simulations, which can further achieve the technical effect of uniform fluid distribution and better meet the needs of the invention of this application.

[0062] Preferably, the porous material is manufactured using 3D printing technology. In the prior art manufacturing process, it is very difficult to achieve a gradual change in the pores of porous materials. The present invention uses 3D printing technology for the capillary structure to achieve a gradual distribution of variable pore density along the flow of the fluid, improves the processing technology, and can achieve accurate regular changes by computer. Compared with the existing preparation process, as long as the gradual printing program is designed, the processing result is more accurate, and the accurate structural amplitude change is achieved through the computer program, which greatly improves the processing accuracy and thus improves the heat exchange efficiency.

[0063] Preferably, the inlet header 21 and the outlet header 22 are designed as a conical structure, and the flow channel area becomes smaller and smaller along the flow direction of the fluid in the inlet header, and the flow channel area becomes larger and larger along the flow direction of the fluid in the outlet header 22. This can further ensure the uniform distribution of the fluid in the flow channel, which can improve the heat exchange efficiency and reduce the overall pressure drop.

[0064] Preferably, the second layer 2 includes a plurality of bent plate-like structures, one side of the plate-like structure forms an inlet branch pipe 23, and the other side forms an outlet branch pipe 24, and the inlet branch pipe 23 and the outlet branch pipe 24 are not directly connected. The fluid flows from the inlet branch pipe 23 to the outlet branch pipe 24 due to the capillary force of the hot fluid capillary layer.

[0065] Preferably, the bent plate-like structure is a V-shaped structure or a trapezoidal structure, which can design more heat exchange microchannels within the same width, increase the heat exchange area, and improve the overall heat exchange capacity while reducing the volume.

[0066] As a preference, Figure 3 As shown, the hole penetrating the second layer can be in the shape of a long strip. The present application sets a through hole in the second layer so that the fluid can enter the third layer 3 through the hole in a targeted manner, and the porous material at the corresponding position of the third layer 3 can be set in a targeted manner. For example, the porous material may not be set at the position where the hole is formed, and the porous material is set at the rest of the positions. In this way, the above setting is realized by 3D printing, avoiding the manufacturing difficulties of the prior art.

[0067] Preferably, the cold fluid inlet 11 and the cold fluid outlet 12 are arranged diagonally on the first layer 1. Such an arrangement can ensure the fluid heat exchange area and reduce the occurrence of short circuit.

[0068] The fourth layer is a hot fluid pipeline layer. A cavity is provided in the fourth layer for the hot fluid to pass through. As a preferred embodiment, Figure 5As shown, a fin matrix is ​​arranged in the cavity, and the fin matrix is ​​arranged in a shuttle (spindle) structure. The present invention arranges a new type of spindle-shaped structure to arrange the fins, which can make the fluid flow along the fins, reduce the flow resistance, further fully exchange heat with the capillary structure, and improve the heat exchange efficiency.

[0069] like Figure 5 As shown, there are multiple fin matrices, and two adjacent fin matrices are connected end to end. Preferably, each fin matrix is ​​divided into multiple layers, and each array includes a central fin and multiple layers of peripheral fins surrounding the central fin, and each layer of fins is a shuttle (spindle) structure. By setting multiple layers, the fluid can fully flow and exchange heat therein.

[0070] A plurality of fin matrices form a group, and the head of the first spindle-shaped structure of each group is opposite to the flow direction of the liquid (facing the flow direction of the fluid), and the tail of the first spindle-shaped structure is connected to the head of the second spindle-shaped structure, and so on, thereby forming a group. By setting up multiple layers, the fluid can fully flow and exchange heat therein, and the flow channel of the fluid frequently flows and changes in volume along the shuttle shape as it flows, further improving the heat exchange efficiency.

[0071] Preferably, both the head and the tail of the spindle-shaped structure are pointed.

[0072] Preferably, the tip angle of the head of the spindle-shaped structure is smaller than the tip angle of the tail. The above structure can make the fluid diffuse slowly along the shuttle shape first, avoiding the low heat exchange effect caused by rapid diffusion, promoting heat exchange, and at the same time promoting the guidance of the fluid, reducing resistance, and improving heat exchange efficiency.

[0073] Preferably, the connecting line of the central fins of each group is in the same direction as the fluid flow direction.

[0074] Preferably, multiple groups of fin matrices are arranged in parallel.

[0075] Preferably, the fin matrix is ​​arranged at corresponding positions between the multiple groups of fins.

[0076] The cavity surface is provided with a streamlined flow guide module composed of a spindle-shaped fin matrix. The symmetrically distributed fins also play a flow guide role in a spindle-shaped distribution on a macro scale, further reducing flow resistance, further fully exchanging heat with the capillary structure, and improving heat exchange efficiency.

[0077] Preferably, the fins extend from the top wall surface to the bottom wall surface of the cavity.

[0078] Preferably, the upper plate of the cavity is the back side of the third layer.

[0079] Preferably, the fins are arranged on the back side of the third layer.

[0080] Preferably, the hot fluid flows in from the center of the fourth layer and then flows out from the four sides, for example Figure 1 The fourth layer is set as follows Figure 6 The bottom of the fourth layer cavity is provided with baffle straight plates 43-46 and fins 47-50, wherein the baffle straight plates include a central baffle straight plate 43 located at the center of the bottom plate, a second baffle straight plate 44 surrounding the outside of the central baffle straight plate 43, a third baffle straight plate 45 surrounding the outside of the second baffle straight plate 44, and an outer baffle straight plate 46 surrounding the outside of the third baffle straight plate 45;

[0081] As a preference, Figure 6 As shown, the central baffle straight plate 43 includes four pieces, each of which includes two baffle straight plate walls that are at a certain angle to each other, and the extension lines of the baffle straight plate walls of the four central baffle straight plates form a first prism, and the baffle straight plate walls form a part of the edge of the first prism; a first interval is set between the baffle straight plate walls of adjacent central baffle straight plates;

[0082] The second baffle straight plates 44 include four pieces, each of which includes two baffle straight plate walls perpendicular to each other, and the extension lines of the baffle straight plate walls of the four second baffle straight plates form a first rectangular structure, and the baffle straight plate walls form a part of the side of the first rectangle; a second interval is set between the baffle straight plate walls of adjacent second baffle straight plates;

[0083] The third baffle straight plates 45 include four pieces, each of which includes two baffle straight plate walls that are at a certain angle to each other, and the extension lines of the baffle straight plate walls 451 of the four third baffle straight plates form a second prism structure, and the baffle straight plate walls form a part of the side of the second prism; a third interval is set between the baffle straight plate walls of adjacent third baffle straight plates 45;

[0084] The external baffle straight plates 46 include two pieces, each of which includes a first straight plate wall and two second straight plate walls perpendicular to each other disposed at both ends of the straight plate wall. The extension lines of the baffle straight plate walls of the two external baffle straight plates form a second rectangular structure, and the first straight plate wall and the second straight plate wall form part of the side of the second rectangle; a fourth interval is set between the adjacent second straight plate walls of the two external baffle straight plates 46.

[0085] Preferably, a plurality of fins 47 are arranged inside the central baffle plate 43; a plurality of fins 48 are arranged between the second baffle plate 44 and the central baffle plate 43; a plurality of fins 49 are arranged between the second baffle plate 44 and the third baffle plate 45; and a plurality of fins 50 are arranged between the third baffle plate 45 and the external baffle plate 46.

[0086] The heat exchanger of the present application is provided with a flow guide structure inside, especially by setting up a multi-layer vertical structure of rectangular prism-shaped baffle straight plates, so that the liquid flow range is wide, the dead zone of cold liquid flow is effectively reduced, and the temperature uniformity of the heat flow surface is further improved.

[0087] In the heat exchanger of the present application, cylindrical fins are arranged inside the central baffle straight plate, between the central baffle straight plate and the second baffle straight plate, between the second and third baffle straight plates, and between the third and outer baffle straight plates, so as to increase the disturbance in the external space, that is, enhance the disturbance of the flow field, and expand the heat exchange area, which is beneficial to enhance the heat exchange, avoid excessive flow resistance, and have a wide range of adaptability.

[0088] Preferably, the extension line of the line connecting the midpoints of the relative first intervals and the extension line of the midpoints of the relative third intervals pass through the vertical point of the two mutually perpendicular baffle straight plate walls 441 of the second baffle straight plate 44 and the vertical point of the two mutually perpendicular baffle straight plate walls 461 of the external baffle straight plate 46.

[0089] Preferably, the extension line of the line connecting the midpoints of the second relative intervals and the extension line of the midpoints of the fourth relative intervals pass through the connection point of the two baffle straight plate walls of the center baffle straight plate 43 that are at a certain angle to each other and the connection point of the two baffle straight plate walls of the third baffle straight plate 45 that are at a certain angle to each other.

[0090] Through the above preferred design, the liquid distribution can be more uniform and the heat exchange effect can be better.

[0091] As a preference, Figure 6 The fourth layer includes a hot fluid inlet 41 and a hot fluid outlet 42 arranged on the back side, the hot fluid inlet 41 is arranged at the center of the first prism, and two hot fluid outlets 42 are arranged, which are respectively arranged at the opposite ends of the second rectangle and arranged outside the first straight plate wall, and the line connecting the center lines of the two outlets 42 passes through the center of the first straight plate wall. Through such an arrangement, the fluid can bypass the outlet after flowing out of the fourth interval, thereby increasing the flow area and improving the heat exchange efficiency.

[0092] Through the above structure, hot liquid flows in from the center area of ​​the cover plate. When the hot liquid just enters the heat exchanger, the temperature is high, the temperature difference with the heat source is large, the heat exchange capacity is strong, and the temperature of the heat source area can be more effectively controlled.

[0093] The present application adopts a single-inlet, multiple-outlet flow mode, so that the cold liquid flows from the middle to both sides, improving the phenomenon of gradual temperature increase along the flow direction caused by the previous single-inlet and single-outlet flow mode, and further improving the uniformity of heat dissipation.

[0094] The baffle plates 43-46 are flow-guiding structures and can be regarded as long straight fins of larger size. By arranging these baffle plates, flow disturbance and heat transfer enhancement can also be achieved.

[0095] Preferably, the hot fluid inlet 41 is located in the middle of the two liquid outlets. Through the above arrangement, the liquid distribution is more uniform and the heat dissipation performance is more uniform.

[0096] The ribs 47 - 50 are cylindrical.

[0097] The height of the fins 47-50 is the same as the height of the baffle straight plates 43-46, and is equal to the height of the square cavity.

[0098] As a preference, Figure 6 As shown, the vertical point positions of the vertical walls of the baffle straight plates 43-46 are provided with streamlined structures, preferably arc-shaped structures. By providing the streamlined structures, the flow resistance of the liquid can be reduced, the dead zone of the liquid can be reduced, and the heat exchange effect can be improved.

[0099] Preferably, the fins are arranged on the back side of the third layer.

[0100] Between the second baffle plate and the third baffle plate, from the center of the fourth layer to the outside, the farther from the center of the fourth layer, the farther the distance between adjacent fins 49. Mainly, as the distance from the center increases and the closer to the third baffle plate, the smaller the flow space of the fluid, the greater the flow resistance. By setting the distance between adjacent fins 49 to be farther, the fluid flow rate remains relatively stable, so that the overall heat exchange can be relatively uniform, avoiding uneven local heating and causing local premature damage.

[0101] It is further preferred that, between the second baffle plate and the third baffle plate, from the center of the fourth layer to the outside, the distance between adjacent fins 49 increases as the distance from the center of the fourth layer increases. The above distribution is also in accordance with the distribution law of fluid flow and heat exchange, and it is found through numerical simulation and experiments that the heat exchange efficiency can be further improved.

[0102] Between the third baffle plate and the fourth vertical plate, from the center of the fourth layer to the outside, the farther from the center of the fourth layer, the farther the distance between adjacent fins 50. This is mainly because as the distance from the center increases, the flow space resistance of the fluid increases, and the flow rate becomes relatively slow. By setting the distance between adjacent fins 50 to be farther, the fluid flow rate remains relatively stable, so that the overall heat exchange can be relatively uniform, avoiding uneven local heating and causing local premature damage.

[0103] Further preferably, between the third baffle plate and the fourth vertical plate, from the center of the fourth layer outward, the farther from the center of the fourth layer, the closer the distance between adjacent fins 50 is, and the amplitude increases continuously. The above distribution is also in line with the distribution law of fluid flow and heat exchange, and it is found through numerical simulation and experiments that the heat exchange efficiency can be further improved.

[0104] In the designed central diffusion flat tube, the fluid enters the cavity of the flat tube from the inlet of the central area of ​​the upper cover, passes through the bottom guide structure, and gradually flows from the central inlet area to the surroundings of the flat tube cavity, and performs convective heat exchange with the surface of each flow channel (including fins) during the flow process. Finally, after mixing at the position where the heat exchange area is connected, the fluid flows out from the outlets on both sides of the flat tube to perform heat exchange.

[0105] However, compared with the traditional solar collector tube plates, the central diffusion flat tube changes the flow mode of single inlet and single outlet of the fluid and replaces it with single inlet and double outlet. Therefore, in this design, the outlet is processed on both sides of the flat tube, which can effectively improve the temperature uniformity of the heat flow surface of the flat tube.

[0106] As a preference, Figure 5 , Figure 6 The fins are elastic components, and the elastic components can make the fluid flush the column fins when it flows, and the column fins will swing in a pulsating manner, thereby promoting descaling, and the vibration causes turbulence, which can also enhance heat transfer.

[0107] As a preference, the elasticity of the fins is reduced along the flow direction of the hot fluid. This is because as research has shown, as the fluid undergoes heat exchange, the fluid temperature becomes lower and lower, making it less likely to accumulate scale, and the degree of scaling becomes lighter along the flow direction of the fluid. Therefore, by setting the degree of elasticity to be continuously reduced, the purpose of further descaling and enhancing heat transfer is achieved, reducing the number of highly elastic heat conductors and reducing costs.

[0108] Further preferably, along the flow direction of the hot fluid, the elasticity of the fins is gradually reduced and the amplitude is continuously increased. The above changes are also based on research findings, in line with the law of scaling, and can further reduce costs, improve heat exchange efficiency, and reduce scaling.

[0109] The working process of the heat exchanger is as follows: the cold fluid is driven by the driving pump to flow from the fluid inlet 11 into the inlet branch pipe 21, and then into the porous material flow channel 22, and then diverted through the inlet branch pipe 23. The fluid is forced to flow downward due to the obstruction at the top of the conical branch pipe, and is received by the inlet flow channel 25 below the branch pipe. Since both sides of the inlet flow channel 25 are porous materials 31, the fluid flows in two opposite directions in the porous material, absorbing the heat transferred by the porous material 31 in the process. After the fluid absorbs heat, it is forced to flow upward, flows through the outlet flow channel 26 to the outlet branch pipe 24, flows out through the outlet of the outlet branch pipe 24, and then merges into the outlet branch pipe 22 to flow out of the porous material flow channel, and finally flows out through the fluid outlet 12. At this point, the entire flow heat exchange process is completed.

[0110] Although the present invention has been disclosed as above with preferred embodiments, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, so the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A plate heat exchanger with a through hole multilayer structure, wherein the first layer, the second layer, the third layer and the fourth layer are arranged in sequence from top to bottom, the first layer includes a cold fluid inlet and a cold fluid outlet arranged on the front, the second layer includes an inlet header, an outlet header, an inlet branch pipe, an outlet branch pipe, an inlet flow channel and an outlet flow channel arranged on the front, wherein the upstream of the inlet header and the downstream of the outlet header are respectively connected to the cold fluid inlet and the cold fluid outlet of the first layer, the inlet header and the outlet header are respectively connected to the inlet branch pipe and the outlet branch pipe, the front of the second layer includes a plurality of bent plate-like structures, the plate-like structures An inlet branch pipe is formed on one side of the structure, and an outlet branch pipe is formed on the other side, and the inlet branch pipe and the outlet branch pipe are not directly connected; a through hole penetrating the second layer is arranged in the inlet branch pipe and the outlet branch pipe, thereby forming an inlet flow channel and an outlet flow channel; the third layer includes a porous material located on the front side, and the porous material is connected to the inlet flow channel and the outlet flow channel; the porous material adopts 3D printing technology, so that the porous material has a variable pore structure, and the pore diameter at the inlet flow channel fluid inlet is larger than the pore diameter at the outlet flow channel fluid outlet; the fourth layer is a thermal fluid pipeline in thermal contact with the third layer; it is characterized in that A plurality of through holes penetrating the second layer are arranged in each inlet and outlet branch pipe, and the aperture of each through hole gradually increases along the flow direction of the fluid in the inlet manifold; along the flow direction of the fluid in the inlet manifold, the amplitude of the gradual increase of the aperture of each through hole becomes larger and larger.

2. The plate heat exchanger according to claim 1, characterized in that: Along the flow direction of the fluid in the inlet header, the pore distribution density of the porous material gradually increases.

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