Heat transfer component, heat exchange component, parallel flow heat exchanger and air heater

Abstract

The present invention is applied to the field of heat exchange, and provides a heat transfer component, including a heat transfer substrate, characterized in that it also includes a fin, the fin having a bottom surface close to the heat transfer substrate, and a vertical surface connected to the bottom surface; the heat transfer substrate includes a heat transfer base surface, wherein the bottom surface side edge of the fin is close to the heat transfer base surface, and a first melting portion connecting the bottom surface side edge and the heat transfer base surface is formed at the junction of the bottom surface side edge of the fin and the heat transfer base surface. The brazing process can be avoided to reduce pollution and energy consumption; at the same time, the service life and reliability of the heat exchange component are improved.

Description

Technical Field

[0001] The invention relates to the field of heat exchange and heat transfer, and in particular to a heat transfer component, a heat exchange component, a parallel flow heat exchanger and an air heater. Background Art

[0002] At present, the fin heat exchange structure widely used is brazed. The upper and lower sides of the heat transfer substrate are connected to the bottom or top surface of the fin by brazing, and a fusion structure is formed between the bottom or top surface of the fin and the surface of the heat transfer base surface 11, thereby reducing the heat transfer resistance on the one hand and improving the connection strength between the two on the other hand. However, brazing connection requires brazing material and brazing furnace, the use of which causes huge pollution and energy consumption on the one hand. How to produce fin heat exchange components in a more energy-saving and environmentally friendly way, and even the production of flat tube fin heat exchangers, has become an urgent problem to be solved.

[0003] At present, the connection between the heat sink and the bottom surface of the fin in the widely used PTC electric heater is often connected by brazing, such as Figure 7 As shown, the bottom surface of the fin 55 can form a fused structure with the heat dissipation base surface of the heat transfer tube 54, thereby reducing the heat transfer resistance on the one hand and improving the connection strength of the two on the other hand. However, brazing connection requires brazing material and brazing furnace. The use of both causes huge pollution and energy consumption on the one hand. Another solution is to first process the module connected by the fin 55 and then connect it to the PTC heater as a component. The PTC part includes an electrode sheet 52 clamped on both sides of the core 53 arranged in the heat transfer tube 54 and an insulating paper 51 wrapping the electrode sheet and the core. Since the maximum temperature that the insulating paper and the PTC core can withstand is less than 400 degrees, brazing heating cannot be performed. Therefore, the connection between the PTC tube and the heat dissipation strip of the current PTC electric heating element is mostly achieved by applying glue to the contact surface of the PTC tube and the heat dissipation strip and then applying electricity to high temperature extrusion and curing. This connection has low strength and poor reliability, and low thermal conductivity, which may lead to substandard product performance in the later stage of operation. At the same time, this processing technology requires each product to be powered on for curing (power is 1-8KW), which lasts for 4-8 minutes, consuming huge amounts of electricity. In addition, the production efficiency is extremely low, and there are serious production bottlenecks. At the same time, since the PTC heater uses silicone heating and curing connection, there is a silicone layer between the components, and the low thermal conductivity is not conducive to the long-term stable operation of the heating element. In particular, it is difficult to solve the problem of electric heaters in some occasions with high cleanliness requirements. Summary of the invention

[0004] The main purpose of the present invention is to provide a heat transfer component, so as to solve the high energy consumption and high pollution caused by the brazing of the current fin heat transfer components.

[0005] To achieve the above-mentioned purpose, the present invention provides a heat transfer component, including a heat transfer substrate and a fin, wherein the fin has a bottom surface close to the heat transfer substrate and a vertical surface connected to the bottom surface; the heat transfer substrate includes a heat transfer base surface, wherein the bottom surface side edge of the fin is close to the heat transfer base surface, and a first melting portion connecting the bottom surface side edge and the heat transfer base surface is formed at the junction of the bottom surface side edge of the fin and the heat transfer base surface.

[0006] The first melting portion is welded to the heat transfer base surface, and the first melting portion extends along the length direction of the joint. A first melting section is formed between the bottom surface at the side of the fin and the heat transfer base surface 11. The first melting section is connected to the first melting portion, and the first melting section is welded to the heat transfer base surface 11, or / and the first melting section is welded to the fin; the first melting section extends toward the center of the bottom surface.

[0007] There is a second gap between the connection between the bottom surface of the fin and the vertical surface of the fin and the heat transfer base surface. A second melting section connected to the first melting part is formed at the connection point of the fins. The second melting section is welded to the heat transfer base surface, or / and the second melting section is welded to the fin; the second melting section extends toward the center of the bottom surface.

[0008] The heat transfer substrate also has a base folded edge, the bottom side of the fin is close to the base folded edge, and a first melting portion connecting the bottom side and the heat transfer base folded edge is formed at the junction of the bottom side of the fin and the heat transfer base folded edge; the fin includes a continuous top surface, a vertical surface and the bottom surface, and adjacent bottom surfaces are arranged at intervals along the length direction of the heat transfer base surface; a second melting portion is formed on the heat transfer base surface between two adjacent fin bottom surfaces, and the second melting portion is connected to the first melting portion.

[0009] The lower part of the fin side forms a fin melting loss area, and the upper edge formed by the fin melting loss area is spaced H from the lower edge of the fin side surface, and the spacing is 1 / 5-1 / 80 times the fin height; the melting loss distance of the fin side surface is 0.2 to 5mm; the lower part of the fin vertical side is welded with the first melting part, and the connecting surface is a curved surface, which protrudes toward the center of the fin

[0010] The present invention also provides a gas-liquid fluid heat exchange component, including a heat exchange shell, which forms a liquid flow channel, and at least one side of the heat exchange shell is formed with a heat transfer component as described above, and the heat exchange shell forms a flat liquid flow channel. The liquid flowing in the liquid flow channel is one or more of a supercooled liquid, a saturated liquid or a gas-liquid mixture.

[0011] The flat flow channel is divided into multiple small flow channels by multiple partitions; the heat exchange efficiency of the inner wall of the liquid flow channel is different, and the heat exchange efficiency of the upper and lower inner wall surfaces on both sides is higher than that of the inner wall surface of the horizontal part of the shell; the outer surface of the heat exchange shell forms a heat transfer base surface 11, and the heat transfer base surface 11 is a plane or a curved surface; the vertical surface of the base surface folded edge is connected with the heat transfer base surface 11 with a thickened convex edge; the first melting part corresponds to one side of the heat exchange base surface, and the corresponding flow channel is a one side flow channel; the unit width flow area of ​​the one side flow channel is greater than the unit width flow area of ​​the middle flow channel; the inner wall surface of the one side flow channel has a heat exchange enhancement structure, and the heat exchange enhancement structure is an internal tooth structure or an inclined internal thread structure.

[0012] The present invention also provides a parallel flow heat exchanger, comprising the gas-liquid fluid heat exchange component as described above, a flat liquid flow channel formed by the shell, a plurality of flat liquid flow channels arranged at intervals, the fins are arranged on both sides of adjacent flat liquid flow channels, at least one end of the flat liquid flow channel is connected to a collecting pipe; the top surface of the fin is in contact with the shell of the flat liquid flow channel located thereon, and the side edge of the top surface of the fin is close to the heat transfer base surface 11 of the bottom surface of the shell, and a first melting portion connecting the side edge of the top surface and the heat transfer base surface 11 of the bottom surface of the shell is formed at the close joint.

[0013] The present invention also provides an air heater, comprising a heat dissipation shell and a heating core arranged in the heat dissipation shell, wherein at least one side of the heat exchange shell is formed with a heat transfer component as described above, and is characterized in that: the fins are used to exchange heat with the air, and the heat transfer base surface forms an accommodating cavity for arranging the PTC electric heating core.

[0014] Electrode sheets are arranged above and below the PTC electric heating core in the accommodating cavity, and insulating paper is arranged outside the electrode sheets. The power supply supplies power to the PTC heating core through the electrode sheets; the heating capacity of the PTC electric heating core corresponding to the upper and lower heat transfer base surfaces at the left and right sides of the accommodating cavity is greater than the heating capacity of the PTC heating core corresponding to the middle area of ​​the heat dissipation substrate.

[0015] Through the above technical solution, by forming a first molten portion between the side of the fin and the heat transfer base surface 11, the fin and the heat transfer base surface 11 are directly welded together. On the one hand, the structural strength is improved and the process is simplified. On the other hand, the molten portion can be connected to multiple positions of the fin to increase the heat transfer effect and improve the heat exchange efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a three-dimensional schematic diagram of an embodiment of a heat transfer component in the present invention;

[0017] Figure 2 It is a three-dimensional schematic diagram of an embodiment of a gas-liquid fluid heat exchange component in the present invention;

[0018] Figure 3 This is an embodiment of the gas-liquid fluid heat exchange component of the present invention. Figure 2 A partial enlarged view of

[0019] Figure 4 It is a three-dimensional schematic diagram of a heat exchange shell of an embodiment of a gas-liquid fluid heat exchange assembly in the present invention;

[0020] Figure 5 It is a three-dimensional schematic diagram of an embodiment of a gas-liquid fluid heat exchange component in the present invention;

[0021] Figure 6 This is an embodiment of the gas-liquid fluid heat exchange component of the present invention. Figure 4 A partial enlarged view of

[0022] Figure 7 It is an exploded diagram of a PTC electric heater in the prior art;

[0023] Figure 8 It is a three-dimensional schematic diagram of an embodiment of an electric heater in the present invention;

[0024] Fig. 9 This is an embodiment of the electric heater of the present invention. Figure 8 A partial enlarged view of

[0025] Fig.10 It is a three-dimensional schematic diagram of an embodiment of an electric heater in the present invention;

[0026] Fig.11 This is an embodiment of the electric heater of the present invention. Fig.10 A partial enlarged view of .

[0027] Reference numerals:

[0028] Among them: 1 is a heat transfer component, an electric heater 10, a heat transfer base surface 11, a base surface folded edge 12, fins 13, a bottom surface 14, a vertical surface 15, a first melting portion 20, a second melting portion 21, an accommodating cavity 24, a gas-liquid fluid heat exchange component 30, an intermediate flow channel 42, an intermediate heat exchange base surface 43, a fluid channel 44, a side flow channel 45, a side heat exchange base surface 46, a side vertical heat exchange base surface 47, and a groove 49. DETAILED DESCRIPTION

[0029] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0030] In the present invention, the gas-liquid fluid heat exchange assembly refers to the heat exchange through the fins on the air flow side, and the liquid flow side is in the heat exchange shell. The heat exchange shell has a heat transfer base surface 11 connected to the fins, so that the gas-liquid fluid flows on the fin side and in the shell respectively, realizing the heat exchange assembly of air flow and liquid flow. High-energy welding refers to the formation of a local molten area on the metal surface to be processed by concentrating energy, and the metal liquid in the molten area maintains fluidity for a short time, and after the energy supply is stopped, the metal liquid in the molten area is solidified by natural temperature drop. High-energy welding can be but not limited to laser welding, high-temperature plasma welding, etc. The fin brazing process in the prior art mentioned in this embodiment refers to the fin being crimped on the surface to be welded by a tooling, and the fin and the surface to be welded are heated as a whole by a brazing furnace, and there is brazing solder on the fin layer and / or the surface to be welded. After high-temperature melting, a molten connection surface is formed on the fin and the surface to be welded. For example, a molten connection surface is formed between the bottom surface of the corrugated fin and the surface to be welded, and there is no gap between the two (the gap here is the situation where air can enter between the two to form a large thermal resistance). After normal brazing processing, the bottom surface of the fin and the welding surface are connected into one by solder, forming a good heat transfer surface on the entire bottom surface.

[0031] The present invention first discloses a heat transfer component 1, such as Figure 1As shown, it includes a heat transfer substrate and a fin 13, wherein the fin has a bottom surface 14 close to the heat transfer substrate 11 and a vertical surface 15 connected to the bottom surface 14; the heat transfer substrate includes a heat transfer base surface 11, wherein the bottom surface side of the fin is close to the heat transfer base surface 11, and a first melting portion 20 connecting the bottom surface side and the heat transfer base surface 11 is formed at the junction of the bottom surface side of the fin and the heat transfer base surface 11. In this way, the first melting portion 20 is fused with the heat transfer base surface 11, and the heat of the heat exchange substrate can be quickly transferred out; at the same time, the first melting portion 20 is connected to the side of the bottom surface 14 of the fin, and the heat can be transferred to the vertical surface of the fin through the bottom surface and the side of the fin, so that heat exchange can be performed efficiently. At the same time, the first melting portion 20 simultaneously connects the fin and the heat exchange substrate to form a solid integrated structure with high structural strength. Among them, the bottom surface 14 of the fin is close to the heat transfer base surface 11, which means that there is a gap between the two. Although the corrugated fin and the heat transfer base surface 11 will be pressed during the processing, the solid has a high hardness, and there must be a gap between them. Since air can enter the gap, a large thermal resistance is formed. Therefore, technical personnel in this field, without adopting specific means, will think that effective heat transfer cannot be carried out between the bottom surface of the fin and the heat transfer base surface 11 in such contact, and it is a technical means that technical personnel in this field are not inclined to adopt. Generally, the bottom surface of the fin and the heat transfer base surface 11 are molten and welded to each other in the form of brazing, so as to break the air in the gap and achieve a good heat exchange effect. In this embodiment, the heat transfer between the heat transfer base surface 11 and the fin is mainly achieved by connecting the heat transfer base surface 11 and connecting the bottom surface and the vertical surface of the fin by the first molten portion and strengthening the heat transfer. There is a gap between the bottom surface of the remaining part and the heat transfer base surface 11, and the heat transfer capacity is relatively small.

[0032] The manufacturing process of this embodiment illustrates the formation of the first molten portion. First, the materials of the fins and the heat transfer base 11 are metals with similar melting points. In some embodiments of the present invention, an alloy with aluminum as the main body is used. Specifically, the fins are fixed and pressed at the predetermined position of the heat transfer base 11 by a tool, and the contact surface between the bottom surface of the fin and the heat transfer base 11 is set in a vertical direction. The contact surface between the bottom surface of the fin and the heat transfer base 11 is aligned by high-energy welding with a protective gas, that is, the heat transfer base 11 is used as the basis, and at the same time, it is ensured that the bottom surface of the fin and the heat transfer base 11 at the heating position are melted by high-energy welding to form the first molten portion. Because high-energy welding concentrates energy to form a local molten area on the metal surface to be processed, and the metal liquid in the molten area maintains fluidity for a short time, and after the energy supply is stopped, the metal liquid in the molten area solidifies due to the natural temperature drop. During the actual processing, when heated at high temperature, some of the lower part of the fin side will melt, and some of the material of the heat transfer base surface 11 will also melt at the heated part of the heat transfer base surface 11, and together they form molten metal liquid. At this time, the position of the bottom surface of the fin side will be closer to the center of the fin than when it is not heated, and at this time there is a first gap between the bottom surface of the fin side and the heat transfer base surface 11, which has an adsorption effect, and liquid metal will flow into the first gap, thereby welding the heat transfer base surface 11 and the bottom surface of the fin side, so that a first melting section is formed in the original first gap, that is, the bottom surface of the fin side and the heat transfer base surface 11 form a first melting section, the first melting section is connected to the first melting part, and the first melting section is welded to the heat transfer base surface 11, or / and the first melting section is welded to the fin. In this way, the heat in the heat exchange substrate can be easily transferred from the first melting section to the gas fluid through both sides of the bottom surface of the fin. At the same time, the first melting section connected to the first melting part further expands the heat transfer path, and the heat on the outside of the side of the fin is transferred to the first melting section through the first melting section, and then transferred to the vertical surface of the fin, which is conducive to diffusion to the central area of ​​the fin through the vertical surface of the fin, thereby improving the heat transfer efficiency. In the high-energy welding process, when the first melting section is still in liquid, it is easy to weld with the bottom surface of the fin, and because there is a first gap between the bottom surface of the fin and the heat transfer base surface 11, the liquid metal flowing in from one side of the bottom surface of the fin will extend along the first gap to the center of the bottom surface of the fin, and when the liquid metal cools down and condenses, it forms the first melting section extending to the center of the bottom surface of the fin. The extension to the center of the bottom surface of the fin can effectively expand the contact area between the first melting section and the bottom surface of the fin and the heat transfer base surface 11, and can effectively expand the area of ​​heat transfer from the heat transfer base surface 11, and at the same time, improve the connection strength between the fin and the heat transfer base surface 11.

[0033] The heat transfer component disclosed in the present invention is a basic heat transfer structure and can be used in a gas-liquid fluid heat exchange component or an air electric heater to form a product or component that is more suitable for application. The following is a combination of a gas-liquid fluid heat exchange component using the heat transfer component disclosed in the present invention to achieve better gas-liquid fluid heat exchange. The specific implementation method is as follows, refer to Figures 2 to 6 shown.

[0034] The present invention discloses a gas-liquid fluid heat exchange component, such as Figure 2 , Figure 3 As shown, it includes a heat exchange shell, which forms a liquid flow channel 44, wherein the heat exchange shell includes at least a heat transfer base surface 11; the heat exchange component also includes a fin 13, and the fin 13 has a bottom surface 14 close to the heat transfer base surface 11, and a vertical surface 15 connected to the bottom surface 14; wherein the heat exchange shell includes the heat transfer base surface 11, wherein the joint between the side of the bottom surface 14 of the fin and the heat transfer base surface 11 forms a first melting portion 20 connecting the side of the bottom surface 14 and the heat transfer base surface 11. In this way, the first melting portion 20 is welded with the heat transfer base surface 11, and the heat of the heat exchange substrate can be quickly transferred out; at the same time, the first melting portion 20 is connected to the side of the bottom surface 14 of the fin, and the heat can be transferred to the vertical surface of the fin through the bottom surface and the side of the fin, so that heat can be efficiently exchanged. At the same time, the first melting portion 20 connects the fin and the heat exchange base to make the two a solid integrated structure with high structural strength. The above heat transfer base surface 11 and the bottom surface of the fin are fused into one at the joint through the first melting part, which has the core structural characteristics of the heat transfer component. In addition, the bottom surface 14 of the fin is close to the heat transfer base surface 11, which means that there is a gap between the two. Although the corrugated fin and the heat transfer base surface 11 will be pressed during the processing, the solid has a high hardness, and there must be a gap between them. Since air can enter the gap, a large thermal resistance is formed. Therefore, technical personnel in this field, without using specific means, will think that effective heat transfer cannot be carried out between the bottom surface of the fin and the heat transfer base surface 11 in contact in this way, which is a technical means that technical personnel in this field are not inclined to adopt. Generally, the bottom surface of the fin and the heat transfer base surface 11 are melted and welded to each other in the form of brazing, so as to break the air in the gap and achieve a good heat exchange effect. In this embodiment, the heat transfer between the heat transfer base surface 11 and the fin is mainly achieved by connecting the heat transfer base surface 11 and connecting the bottom surface and the vertical surface of the fin by the first melting part and strengthening the heat transfer. There is a gap between the bottom surface of the remaining part and the heat transfer base surface 11, and the heat transfer capacity is relatively small.

[0035] Wherein, the heat exchange shell forms a liquid flow channel 44. Taking the heat transfer of liquid to the outside as an example, the liquid can be water, aqueous solution, oil, or refrigerant. The heat exchange liquid can flow through the liquid flow channel and transfer heat to the outside through the heat exchange shell. Since the bottom side of the fin is connected to the heat transfer base surface 11 of the heat exchange shell through the first melting part, the heat here can be easily transferred to the fin vertical surface 15 through the bottom side or the first melting part, and then transferred to the gas through the fin vertical surface to heat the gas. In this embodiment, the rest of the bottom surface of the fin is close to the heat transfer base surface 11, but due to the gap between the solids, the heat transfer efficiency is affected.

[0036] In some embodiments, Figure 5 and Figure 6As shown, the gas-liquid fluid heat exchange assembly includes a heat exchange shell, which forms a liquid flow channel 44, wherein the heat exchange shell includes at least a heat transfer base surface 11; the heat exchange assembly also includes a fin 13, which has a bottom surface 14 close to the heat transfer base surface 11, and a vertical surface 15 connected to the bottom surface 14; wherein the heat exchange shell includes a heat transfer base surface fold 12, wherein the joint between the side of the bottom surface 14 of the fin and the heat transfer base surface fold 12 close to form a first melting portion 20 connecting the side of the bottom surface 14 and the heat transfer base surface fold 12. The base surface fold 12 is formed by the heat transfer base surface 11 and the adjacent shell vertical surface. Since the cross section formed at the fold is a right angle, more molten metal liquid can be supplied in the case of high-energy welding, so in the case of the welded structural base surface fold 12, more molten metal will be generated, thereby increasing the volume of the first melting portion, and further extending the liquid metal to extend to a distance along the gap, so as to expand the contact area, improve the heat exchange area and the connection consolidation. In this way, the first melting part 20 is welded with the heat transfer base surface fold 12, and the heat of the heat exchange substrate can be quickly transferred from the horizontal and vertical surfaces of the heat transfer base surface fold; at the same time, the first melting part 20 is connected to the side of the bottom surface 14 of the fin, and the heat can be transferred to the vertical surface of the fin through the bottom surface and the side of the fin, so that heat exchange can be performed efficiently. At the same time, the first melting part 20 simultaneously connects the fin and the heat transfer base surface fold 12 to make the two a consolidated integrated structure with high structural strength. Among them, the bottom surface 14 of the fin is close to the heat transfer base surface 11, which means that there is a gap between the two. Although the corrugated fin and the heat transfer base surface 11 will be pressed during the processing, the solid has a high hardness, and there must be a gap between them. Since air can enter the gap, a large thermal resistance is formed. Therefore, technical personnel in this field, without adopting specific means, will think that effective heat transfer cannot be performed between the bottom surface of the fin and the heat transfer base surface 11 in contact, which is a technical means that technical personnel in this field are not inclined to adopt. Generally, the bottom surface of the fin and the heat transfer base surface 11 are melted and welded by brazing, thereby removing the air in the gap and achieving a good heat exchange effect. In this embodiment, the heat transfer between the heat transfer base surface fold 12 and the fin is mainly achieved by connecting the heat transfer base surface 11 and connecting the bottom surface and the vertical surface of the fin by the first molten portion and strengthening the heat transfer. There is a gap between the bottom surface of the remaining part and the heat transfer base surface 11, and the heat transfer capacity is relatively small.

[0037] The heat exchange shell forms a liquid flow channel 44. Taking the heat transfer of liquid outward as an example, the heat exchange liquid can flow through the liquid flow channel and transfer heat outward through the vertical surface and horizontal surface of the heat transfer base surface 11 of the heat exchange shell. Since the bottom side of the fin is connected to the heat transfer base surface fold 12 of the heat exchange shell through the first melting part 20, the heat here can be easily transferred to the fin vertical surface 15 through the bottom side or the first melting part, and then transferred to the gas through the fin vertical surface to heat the gas. In this embodiment, the rest of the bottom surface of the fin (except the side) is close to the heat transfer base surface 11, but due to the gap between the solids, the heat transfer efficiency is affected.

[0038] In some embodiments, Figure 4 As shown, the heat exchange shell forms a flat liquid flow channel, which is conducive to forming a relatively large contact area with the heat transfer base surface 11, and at the same time allows the liquid in the liquid flow channel to flow smoothly. In some other embodiments, the flat liquid flow channel is divided into multiple small flow channels by multiple partitions, so that the heat exchange of the liquid in the flow channel is more uniform, and will not be affected by the refrigerant conditions of the surrounding flow channels. A heat transfer base surface folding edge is provided, wherein the vertical surface of the base surface folding edge is connected to the heat transfer base surface 11 with a thickened convex edge. The thickened convex edge is used to improve the strength of the base surface folding edge on the one hand, and to avoid the molten metal liquid formed by high-energy welding from taking away more materials of the vertical shell, thereby reducing the shell strength at the base surface folding edge. At the same time, the volume of the material that can enter the molten metal liquid is increased, the first melting part is increased, and the length of the first melting section and the second melting section penetrating into the gap is increased, and the heat exchange area is increased. At the same time, the increased heat exchange area can help heat to be transferred from the side vertical heat exchange base surface 47 along the base surface folding edge to the upper and lower base surfaces, thereby improving the heat exchange efficiency. In some embodiments, the thickened convex edge is formed by die extrusion molding. In other embodiments, the convex edge at the folded edge of the base surface is formed by extruding a groove 49 in the middle of the side elevation. Since in the embodiments of the present invention, the heat exchange between the heat exchange substrate and the fin is uneven, the heat exchange at the side edge of the bottom surface of the fin will be more favorable. Relatively speaking, the heat exchange efficiency of the inner wall surface of the liquid flow channel is different, and the heat exchange efficiency of the upper and lower inner wall surfaces on both sides is higher than that of the inner wall surface of the horizontal part of the shell. That is, the inner wall surface of the liquid flow channel of the side flow channel 45 at the corresponding position of the side edge of the bottom surface of the fin has a structure to enhance the heat exchange efficiency, such as the use of local internal teeth, or the formation of inclined internal threads, which increases the area of ​​heat exchange on the one hand, and at the same time, cuts off and reduces laminar flow to improve the turbulent heat exchange efficiency. In some embodiments, as shown in the figure, the outer surface of the heat exchange shell forms a heat transfer base surface 11, and the heat transfer base surface 11 is a plane, which reduces processing costs and reduces the process difficulty of the product; the outer surface of the heat exchange shell forms a heat transfer base surface 11, and the heat transfer base surface 11 can also be a curved surface, such as an arc surface, and the fins are also pressed on the heat transfer base surface 11 on the outer surface of the heat exchange shell in the shape of an arc. In some special occasions, such as direct application in a circular air duct, this reduces the modification of the air duct and reduces the flow resistance of the gas flow channel.

[0039] In some embodiments, the heat exchange shell forms a flat liquid flow channel, and the liquid flowing in the liquid flow channel is water, wherein water is a supercooled liquid at normal temperature, away from its own gas-liquid two-phase line, and heats or cools the gas outside through water. In some cases, the liquid flowing in the liquid flow channel is a volatile refrigerant, such as R290. When the degassing liquid fluid heat exchange component is applied to the evaporation condition, the R290 refrigerant that exchanges heat with the air may be in any form of a supercooled liquid, a saturated liquid or a gas-liquid mixture, that is, under certain circumstances, during the process of flowing in a section of the liquid flow channel, the R290 refrigerant gradually changes from one state to another. When the refrigerant liquid flows along the liquid flow channel, in order to enhance the heat exchange, a partition section is set in the flow channel to separate the flow channel so that the fluid turns and impacts, thereby improving the heat exchange efficiency; or a protrusion that enhances the heat exchange is set in the flow channel to destroy the laminar flow in the flow and improve the heat exchange efficiency on the liquid side.

[0040] In some embodiments, Figure 4As shown, the heat exchange shell forms a flat heat exchange fluid channel 44, which is formed with an intermediate flow channel 42 and a side flow channel 45, wherein the intermediate flow channel 42 corresponds to the intermediate heat exchange base surface 43, on which a fin bottom surface (not shown in the figure) is arranged. Since there is a gap between the fin bottom surface and the heat transfer base surface 11, the heat exchange efficiency is low. On both sides of the flow channel, the first melting portion corresponds to a side heat exchange base surface 46, and the corresponding flow channel is a side flow channel 45, wherein the unit width flow area of ​​the side flow channel 45 is greater than the unit width flow area of ​​the intermediate flow channel 42. Therefore, since the heat exchange between the heat exchange substrate and the fin is uneven, the heat exchange at the side of the fin bottom surface will be more favorable. Relatively speaking, the area of ​​the liquid flow in the flow channel is also different, that is, the flow channel area at the first melting portion on both sides of the flow channel is greater than the flow channel area in the middle of the flow channel. Since the heat exchange capacity on both sides of the flow channel is large, increasing the area of ​​the fluid flowing there can allow more fluid to exchange heat, thereby increasing the local heat exchange amount, thereby improving the overall heat exchange efficiency. At the same time, the method of increasing the local flow channel area in this embodiment can be combined with the technical means for improving the heat exchange efficiency in the previous embodiment to further improve the overall heat exchange efficiency. In this embodiment, the flow channel area corresponding to the first melting part on both sides of the flow channel is greater than the flow channel area in the middle of the flow channel, which is achieved by increasing the height of the flow channel there. In some other embodiments, it is achieved by reducing the flow channel area corresponding to the center of the fin, such as by locally increasing the thickness of the heat exchange shell there. Although this weakens the thickness of the heat transfer body where the bottom surface of the middle fin is attached to the heat transfer base surface 11, it will reduce the refrigerant flow rate at this place and increase the thermal resistance of heat exchange, which does not conform to the conventional technical means and conventional cognition of technicians in this field. However, by reducing the flow area there, more fluid passes through the flow channels corresponding to the first melting parts on both sides, which is a specific occasion where the technical solution of the present invention is used to obtain a better heat exchange effect.

[0041] The manufacturing process of this embodiment illustrates the formation of the first molten portion. First, the materials of the fins and the heat transfer base 11 are metals with similar melting points. In some embodiments of the present invention, an alloy with aluminum as the main body is used. Specifically, the fins are fixed and pressed at the predetermined position of the heat transfer base 11 by a tool, and the contact surface between the bottom surface of the fin and the heat transfer base 11 is set in a vertical direction. The contact surface between the bottom surface of the fin and the heat transfer base 11 is aligned by high-energy welding with a protective gas, that is, the heat transfer base 11 is used as the basis, and at the same time, it is ensured that the bottom surface of the fin and the heat transfer base 11 at the heating position are melted by high-energy welding to form the first molten portion. Because high-energy welding concentrates energy to form a local molten area on the metal surface to be processed, and the metal liquid in the molten area maintains fluidity for a short time, and after the energy supply is stopped, the metal liquid in the molten area solidifies due to the natural temperature drop. During the actual processing, when heated at high temperature, some of the lower part of the fin side will melt, and some of the material of the heat transfer base surface 11 will also melt at the heated part of the heat transfer base surface 11, and together they form molten metal liquid. At this time, the position of the bottom surface of the fin side will be closer to the center of the fin than when it is not heated, and at this time there is a first gap between the bottom surface of the fin side and the heat transfer base surface 11, which has an adsorption effect, and liquid metal will flow into the first gap, thereby welding the heat transfer base surface 11 and the bottom surface of the fin side, so that a first melting section is formed in the original first gap, that is, the bottom surface of the fin side and the heat transfer base surface 11 form a first melting section, the first melting section is connected to the first melting part, and the first melting section is welded to the heat transfer base surface 11, or / and the first melting section is welded to the fin. In this way, the heat in the heat exchange substrate can be easily transferred from the first melting section to the gas fluid through both sides of the bottom surface of the fin. At the same time, the first melting section connected to the first melting part further expands the heat transfer path, and the heat on the outside of the side of the fin is transferred to the first melting section through the first melting section, and then transferred to the vertical surface of the fin, which is conducive to diffusion to the central area of ​​the fin through the vertical surface of the fin, thereby improving the heat transfer efficiency. In the high-energy welding process, when the first melting section is still in liquid, it is easy to weld with the bottom surface of the fin, and because there is a first gap between the bottom surface of the fin and the heat transfer base surface 11, the liquid metal flowing in from one side of the bottom surface of the fin will extend along the first gap to the center of the bottom surface of the fin, and when the liquid metal cools down and condenses, it forms the first melting section extending to the center of the bottom surface of the fin. The extension to the center of the bottom surface of the fin can effectively expand the contact area between the first melting section and the bottom surface of the fin and the heat transfer base surface 11, and can effectively expand the area of ​​heat transfer from the heat transfer base surface 11, and at the same time, improve the connection strength between the fin and the heat transfer base surface 11.

[0042] In some embodiments, the connection between the fin vertical surface and the fin bottom surface is close to the heat transfer base surface 11, such as Figure 2 and Figure 3The corrugated fins in the embodiment, the sinusoidal fins and the rectangular fins used in other embodiments all have a connection close to the heat transfer base surface 11. That is, there is a second gap between the connection between the bottom surface of the fin and the vertical surface of the fin and the heat transfer base surface 11. When high-energy welding concentrates energy to form a local molten area on the metal surface to be processed, and the metal liquid in the molten area maintains fluidity for a short time, and after the energy supply is stopped, the metal liquid in the molten area solidifies due to the natural temperature drop. In the actual processing, when heated at high temperature, some of the lower part of the fin side will melt to form a melt loss area, and some of the material of the heat transfer base surface 11 will melt at the heated part of the heat transfer base surface 11, together forming a molten metal liquid. At this time, the position of the bottom surface of the fin side will be closer to the center of the fin than when it is not heated, and at this time, there is a second gap between the connection between the bottom surface of the fin and the vertical surface of the fin and the heat transfer base surface 11. If there is an adsorption effect, liquid metal will flow into the second gap, so that the heat of the molten metal liquid in the second gap can be easily dissipated from the vertical surfaces on both sides of the bottom surface of the fin, thereby forming a second melting section connected to the first melting part. That is, there is a second melting section between the connection between the bottom surface of the fin and the vertical surface of the fin and the heat transfer base surface 11, the second melting section is connected to the first melting part, the second melting section is welded to the heat transfer base surface 11, or / and the melting section is welded to the fin; the second melting section extends to the center of the bottom surface. In some embodiments, a second melting section connected to the melting part is formed at the connection of the fins, and the second melting section is welded to the heat transfer base surface 11. Therefore, the second melting section can effectively transfer heat from the heat transfer base surface 11, and efficiently transfer it to the fin vertical surface through the connection between the bottom surface and the vertical surface of the fin. During the high-energy welding process, when the second melting section is still in liquid, it is easy to weld with the bottom surface and the vertical surface of the fin, and because there is a second gap between the connection between the bottom surface and the vertical surface of the fin and the heat transfer base surface 11, the liquid metal flowing in from the side of the fin will extend along the second gap to the connection between the bottom surface and the vertical surface of the fin to the center of the fin, and when the liquid metal cools down and condenses, it forms a second melting section extending from the connection between the bottom surface and the vertical surface of the fin to the center of the fin. The extension to the center of the bottom surface and the vertical surface of the fin can effectively expand the contact area of ​​the second melting section with the bottom surface, the vertical surface of the fin, and the heat transfer base surface 11, and can effectively expand the area of ​​heat transfer from the heat transfer base surface 11, and at the same time, improve the connection strength between the fin and the heat transfer base surface 11.

[0043] In some embodiments, Figures 2 to 3As shown, the fin 13 includes a continuous top surface, a vertical surface 15 and the bottom surface 14, and the adjacent bottom surfaces 14 are arranged in the length direction of the heat transfer base surface 11 at intervals, and there is a first gap between the fin bottom surface 14 and the heat transfer base surface 1111, wherein the ratio of the fin width to the length of the heat transfer base surface 11 ranges from 1 / 2 to 1 / 200. Due to the first gap between the fin bottom surface 14 and the heat transfer base surface 1111, the heat exchange performance between the two is poor, and it is necessary to increase the ratio of the first melting portion in the fin connecting the fin and the heat transfer base surface 11. When the fin width is large and the length direction of the heat exchanger base surface is small, the method of the present invention will significantly reduce the overall heat exchange efficiency of the heat exchange component due to too many fin bottom surfaces with poor heat transfer efficiency and the length of the first melting portion formed on the side of the fin bottom surface is too short. Therefore, in multiple embodiments, the ratio range can be 1 / 3; 1 / 8, 1 / 25, 1 / 110, etc., all of which have a high heat exchange effect. In some embodiments, there is a situation where the top surface and the bottom surface of the fin are respectively connected to the top surface or the bottom surface through the first fusion portion and are welded to the heat transfer base surface. This is formed by the different placement positions of the heat transfer structure. In the case of different placement positions, it can be used as a technical solution for the bottom surface or the top surface, and it is also considered that the technical solution of the present invention is adopted.

[0044] In some embodiments, high-energy welding is performed only at the contact point between the side edge of the bottom surface of the fin and the heat transfer base surface 11 or the base surface folded edge, thereby reducing the energy consumption of high-energy welding. Figure 2 and Figure 3 In other embodiments, the high energy welding torch works continuously, i.e. Figure 4 and Figure 5As shown, a second melting portion is formed on the heat transfer base surface 11 between the two adjacent fin bottom surfaces, and the second melting portion is connected to the first melting portion and the second melting section; or a second melting portion is formed on the base surface fold between the two adjacent fin bottom surfaces, and the second melting portion is connected to the first melting portion and the second melting section. Compared with the center height of the first melting portion, the center of the second melting portion is closer to the center of the corresponding fin. Therefore, the first melting portion has a better contact area with the fin, further improving the heat exchange efficiency. At the same time, the heat transfer base surface 11 or the base surface folded edge between the fins is heated and melted by high-energy welding to form liquid molten metal. This part of the molten metal, especially in the case of the second gap between the connection between the vertical surface and the bottom surface of the fin and the base surface, a part of the liquid metal forming the second molten portion is also absorbed into the gap, thereby increasing the heat exchange area of ​​the second molten section, thereby improving the heat exchange efficiency; at the same time, the heat transfer base surface 11 or the base surface folded edge between the fins is heated and melted by high-energy welding to form liquid molten metal. This part of the molten metal, especially in the case of the first gap between the bottom surface of the fin and the base surface, a part of the liquid metal forming the second molten section is also absorbed into the gap, thereby increasing the heat exchange area of ​​the first molten section, thereby improving the heat exchange efficiency.

[0045] In some embodiments, Figure 2 , Figure 3 , Figures 5 and 6 In the invention, corrugated fins are used, which have the advantages of easy purchase and mature technology; in the case of adopting the technical solution of the present invention, the fins can also be rectangular fins, trapezoidal fins, etc., because the connection structure between the fins and the heat transfer base surface 11 or the base surface fold is longer, the length of the bottom side can be effectively increased, thereby increasing the length of the first melting part, which is beneficial to improving the heat exchange efficiency. Moreover, punching seams can be formed on the vertical surface of the fins, which is beneficial to improving the heat exchange on the air side.

[0046] In some embodiments, Figure 2 and Figure 3The lower part of the side of the fin forms a fin melt loss area. The formation of the melt loss area is due to the fact that in order to form more molten metal liquid and keep the liquid molten metal for a longer time during high-energy welding, taking laser welding as an example, the irradiation point of the laser welding gun will reciprocate, that is, forming a laser irradiation area of ​​a certain width to increase the volume of the molten metal liquid and keep it in liquid state for a longer time so that the molten metal liquid can penetrate and expand. The melt loss area is formed at the lower part of the side of the fin here, that is, the vertical side part of the fin is melted by high-energy welding, contributing some fin material to form a melting area, which can effectively increase the amount of molten metal liquid, thereby expanding the heat transfer melting volume and improving the heat exchange efficiency. The distance H between the upper edge formed by the fin melt loss area and the lower edge of the fin bottom surface is 1 / 5-1 / 80 times the fin height; the melt loss distance of the fin side surface is 0.2 to 5mm; the lower part of the side of the fin vertical surface is welded to the first molten part, and the connecting surface is a curved surface, which protrudes toward the center of the fin. There are some melt losses through the vertical surface and the bottom surface of the lower side of the fin. Although some heat transfer area to the vertical surface of the fin is sacrificed, it is not preferred by technical personnel in this field. However, in the technical solution disclosed in the present invention, the melt loss area at the lower part of the side of the vertical surface of the fin can increase the volume of the molten metal liquid to a certain extent, thereby increasing the contact area between the first melting part, the first melting section and the second melting section and the bottom surface of the fin, or the side of the vertical surface; and the melt loss area at the lower part of the side of the vertical surface of the fin can increase the volume of the molten metal liquid to a certain extent, thereby increasing the contact area between the first melting part, the first melting section and the second melting section and the heat transfer base surface 11 or the folded edge of the heat transfer base surface; thereby improving the energy efficiency of heat exchange.

[0047] The present invention also discloses a parallel flow heat exchanger, which adopts the gas-liquid fluid heat exchange assembly mentioned in the above embodiment. The heat exchange shell used in the parallel flow heat exchanger forms a flat liquid flow channel, and a plurality of flat liquid flow channels are arranged at intervals. The fins are arranged between adjacent flat liquid flow channels, and at least one end of the flat liquid flow channel is connected to a header. The parallel flow heat exchanger supplies and discharges liquid to the plurality of flat liquid flow channels through the header, and the plurality of flat liquid flow channels perform heat exchange through a plurality of rows of fins to transfer heat to the air or obtain heat from the air.

[0048] In some embodiments, further, the top surface of the fin contacts the shell of the flat liquid flow channel located thereon, and the side edge of the top surface of the fin is close to the heat transfer base surface 11 of the bottom surface of the shell, and a first melting portion connecting the side edge of the top surface and the heat transfer base surface 11 of the bottom surface of the shell is formed at the close joint; or the side edge of the top surface of the fin is close to the folded edge of the heat transfer base surface of the bottom surface of the shell, and a first melting portion connecting the side edge of the top surface and the folded edge of the heat transfer base surface is formed at the close joint along the extension direction of the folded edge of the heat transfer base surface. In this way, a heat exchange enhancement structure is formed on both sides of the top and bottom of the flat liquid flow channel, which is more conducive to the heat exchange of the liquid fluid. In particular, when there is liquid refrigerant below the flat liquid flow channel, such as in the case of gas-liquid two-phase flow, the liquid will gather in the lower part due to its weight and flow, so that the top surface and side edges of the fins are close to the heat transfer base surface of the bottom surface of the shell, and at the same time, a first melting portion connecting the side edge of the top surface and the folded edge of the heat transfer base surface is formed at the close joint along the extension direction of the folded edge of the heat transfer base surface, which will enhance the heat exchange of the liquid in the lower part of the flat liquid flow channel and significantly improve the heat exchange efficiency.

[0049] The following is a description of an electric heater using the heat transfer assembly disclosed in the present invention to achieve better heat dissipation of the electric heater. Figures 7 to 11 shown.

[0050] The present invention also discloses an electric heater 10, such as Figure 8 and Fig. 9As shown, it includes a heat dissipation shell and a heating core arranged in the heat dissipation shell, the heat dissipation shell at least includes a heat transfer base surface 11 for transferring heat outward; it also includes fins 13, the fins 13 have a bottom surface 14 close to the heat transfer base surface 11, and a vertical surface 15 connected to the bottom surface 14; the heat dissipation shell includes the heat transfer base surface 11, wherein the side of the bottom surface 14 of the fin is close to the heat transfer base surface 11, and a first melting portion 20 connecting the side of the bottom surface 14 and the heat transfer base surface 11 is formed in the extension direction of the junction of the side of the bottom surface of the fin and the heat transfer base surface. In this way, the first melting portion 20 is fused with the heat transfer base surface 11, which can quickly transfer the heat of the heat dissipation substrate; at the same time, the first melting portion 20 is connected to the side of the bottom surface 14 of the fin, and the heat can be transferred to the vertical surface of the fin through the bottom surface and the side of the fin, so that heat exchange can be carried out efficiently. The above heat transfer base surface 11 and the bottom surface of the fin are fused into one at the joint through the first melting part, and have the core structural characteristics of the heat transfer component. The first melting part 20 connects the fin and the heat dissipation substrate at the same time to make the two a consolidated integrated structure with high structural strength. Among them, the bottom surface 14 of the fin is close to the heat transfer base surface 11, which means that there is a gap between the two. Although the corrugated fins and the heat transfer base surface will be compressed during the processing, the solid has a high hardness and there must be a gap between them. Since air can enter the gap, a large thermal resistance is formed. Therefore, technical personnel in this field, without adopting specific means, will think that effective heat transfer cannot be carried out between the bottom surface of the fin and the heat transfer base surface in such contact, which is a technical means that technical personnel in this field are not inclined to adopt. Generally, the bottom surface of the fin and the heat transfer base surface are molten and welded to each other in the form of brazing, thereby breaking the air in the gap and achieving a good heat exchange effect. In this embodiment, the heat transfer between the heat transfer base surface and the fin is mainly achieved by connecting the heat transfer base surface and connecting the bottom surface and the vertical surface of the fin through the first melting portion and strengthening the heat transfer, or by strengthening the heat transfer through the first melting section and the second melting section which will be described in detail later. There is a gap between the bottom surface of the remaining part and the heat transfer base surface, and the heat transfer capacity is very small.

[0051] Among them, the heat dissipation shell forms an accommodating cavity 24, and a heating core is arranged in the accommodating cavity 24. The heating core can be a resistance wire or a PTC heating element. Compared with the PTC electric heater in the background technology, the welding structure of this embodiment can directly weld the fins to the outside of the heat dissipation shell without brazing the fins and the heat sink, thereby reducing the heat sink components; on the other hand, it is no longer necessary to glue the heat sink and the outside of the heat dissipation shell together through self-heating, thereby reducing the heat transfer resistance of the glue layer, as well as the problems of reliability and impurity addition of the glue layer.

[0052] In some embodiments, Fig.10 and Fig.11As shown, the electric heater includes a heat dissipation shell and a heating core 23 (not shown in the figure) arranged in the heat dissipation shell, the heat dissipation shell includes at least a heat transfer base surface 11 for transferring heat outward; and also includes a fin 13, the fin 13 has a bottom surface 14 close to the heat transfer base surface 11, and a vertical surface 15 connected to the bottom surface 14; the heat dissipation shell includes a heat transfer base surface 11, wherein the side edge of the fin is close to the folded edge 12 of the heat transfer base surface, and a first melting portion 20 connecting the side edge of the bottom surface 14 and the folded edge 12 of the heat transfer base surface is formed at the close joint along the side extension direction. The base surface fold 12 is formed by the heat transfer base surface 11 and the adjacent shell vertical surface. Since the cross section formed at the fold is a right angle, more molten metal liquid can be supplied under high-energy welding conditions. Therefore, in the case of the welded structural base surface fold 12, more molten metal will be produced, thereby increasing the volume of the first molten portion, and further extending the liquid metal to extend farther along the gap to expand the contact area, improve the heat exchange area and connection solidity. In this way, the first molten portion 20 is welded with the base surface fold 12, and the heat of the heat exchange substrate can be quickly transferred from the horizontal and vertical surfaces of the heat transfer base surface fold; at the same time, the first molten portion 20 is connected to the side of the bottom surface 14 of the fin, and the heat can be transferred to the vertical surface of the fin through the bottom surface and the side of the fin, so that heat exchange can be carried out efficiently. At the same time, the first molten portion 20 simultaneously connects the fin and the base surface fold 12 to form a solid integrated structure with high structural strength. Among them, the bottom surface 14 of the fin is close to the folded edge 12 of the heat transfer base surface, which means that there is a gap between the two. Although the corrugated fin and the heat transfer base surface will be pressed during the processing, the solid has a high hardness, and there must be a gap between them. Since air can enter the gap, a large thermal resistance is formed. Therefore, technical personnel in this field, without using specific means, will think that effective heat transfer cannot be carried out between the bottom surface of the fin and the heat transfer base surface in such contact, which is a technical means that technical personnel in this field are not inclined to adopt. Generally, the bottom surface of the fin and the heat transfer base surface are molten and welded to each other by brazing, so as to break the air in the gap and achieve a good heat exchange effect.

[0053] Among them, the heat dissipation shell forms an accommodating cavity 24, and a heating core is arranged in the accommodating cavity 24. The heating core can be a resistance wire or a PTC heating element. Compared with the PTC electric heater in the background technology, the welding structure of this embodiment can directly weld the fins to the outside of the heat dissipation shell without brazing the fins and the heat sink, thereby reducing the heat sink components; on the other hand, it is no longer necessary to glue the heat sink and the outside of the heat dissipation shell together through self-heating, thereby reducing the heat transfer resistance of the glue layer, as well as the problems of reliability and impurity addition of the glue layer.

[0054] The manufacturing process of this embodiment illustrates the formation of the first molten portion. First, the materials of the fins and the heat transfer base 11 are metals with similar melting points. In some embodiments of the present invention, an alloy with aluminum as the main body is used. Specifically, the corrugated fins are fixed and pressed at a predetermined position on the heat transfer base by a tool, and the contact surface between the bottom surface of the fin and the heat transfer base is set in a vertical direction. The contact surface between the bottom surface of the fin and the heat transfer base is aligned with high-energy welding with a protective gas, that is, based on the heat transfer base, while ensuring that the gap between the bottom surface of the fin and the heat transfer base is melted by high-energy welding, and the first molten portion is formed at the same time. Because high-energy welding concentrates energy to form a local molten area on the metal surface to be processed, and the metal liquid in the molten area maintains fluidity for a short time, and after the energy supply is stopped, the metal liquid in the molten area solidifies due to the natural temperature drop. In the actual processing, when heated at high temperature, some of the lower part of the fin side will melt, and some of the material of the heat transfer base surface will melt at the heated part of the heat transfer base surface, forming molten metal liquid together. At this time, the position of the bottom surface of the fin side will be closer to the center of the fin than when it is not heated, and there is a first gap between the bottom surface of the fin side and the heat transfer base surface. When there is an adsorption effect, liquid metal will flow into the first gap, so that heat can easily dissipate from the vertical surfaces on both sides of the bottom surface of the fin in the first gap, thereby forming a first melting section connected to the first melting part. That is, the bottom surface of the fin side and the heat transfer base surface 11 form a first melting section, which is connected to the first melting section, and the first melting section is welded to the heat transfer base surface 11, or / and the first melting section is welded to the fin. In this way, the heat in the heat dissipation substrate can be easily dissipated from the first melting section to the gas fluid through both sides of the bottom surface of the fin. At the same time, the first melting section connected to the first melting part further expands the heat transfer path, and the heat on the outer side of the fin side is relayed to the first melting section through the first melting section, and then transferred to the vertical surface of the fin, which is conducive to diffusion to the central area of ​​the fin through the vertical surface of the fin, thereby improving the heat transfer efficiency. In the high-energy welding process, when the first melting section is still in liquid, it is easy to weld with the bottom surface of the fin, and because there is a first gap between the bottom surface of the fin and the heat transfer base surface, the liquid metal flowing in from one side of the bottom surface of the fin will extend along the first gap to the center of the bottom surface of the fin, and when the liquid metal cools down and condenses, it forms the first melting section extending to the center of the bottom surface of the fin. The extension to the center of the bottom surface of the fin can effectively expand the contact area between the first melting section and the bottom surface of the fin and the heat transfer base surface, and can effectively expand the area of ​​heat transfer from the heat transfer base surface, and at the same time, improve the connection strength between the fin and the heat transfer base surface.

[0055] In some embodiments, the connection between the fin vertical surface and the fin bottom surface is close to the heat transfer base surface, such as Figure 8 and Fig. 9The corrugated fins in the embodiment, or the sine wave fins and rectangular fins in other embodiments will have a connection close to the heat transfer base surface. That is, there is a second gap between the connection between the bottom surface of the fin and the vertical surface of the fin and the heat transfer base surface. When high-energy welding concentrates energy to form a local melting area on the metal surface to be processed, and the metal liquid in the melting area maintains fluidity for a short time, and after the energy supply is stopped, the metal liquid in the melting area is solidified by natural temperature drop. In the actual processing process, when heated at high temperature, some of the lower part of the side of the fin will melt to form a melting loss area, and some of the material of the heat transfer base surface will also melt at the heated part of the heat transfer base surface, forming a molten metal liquid together. At this time, the position of the bottom surface of the side of the fin will be closer to the center of the fin than when it is not heated, and at this time, there is a second gap between the connection between the bottom surface of the fin and the vertical surface of the fin and the heat transfer base surface. If there is an adsorption effect, liquid metal will flow into the second gap, so that heat can easily dissipate from the vertical surfaces on both sides of the bottom surface of the fin in the second gap, thereby forming a second melting section connected to the first melting part. That is, there is a second melting section between the connection between the bottom surface of the fin and the vertical surface of the fin and the heat transfer base surface 11, the second melting section is connected to the first melting part, the second melting section is fused to the heat transfer base surface 11, or / and the melting section is fused to the fin; the second melting section extends toward the center of the bottom surface. Thus, the second melting section can effectively transfer heat from the heat transfer base surface and efficiently transfer it to the fin vertical surface through the connection between the bottom surface and the vertical surface of the fin. During the high-energy welding process, when the second molten section is still in liquid, it is easy to weld with the bottom and vertical surfaces of the fins. Since there is a second gap between the connection between the bottom and vertical surfaces of the fins and the heat transfer base surface, the liquid metal flowing in from the side of the fin will extend along the second gap to the connection between the bottom and vertical surfaces of the fins toward the center of the fins. When the liquid metal cools down and condenses, a second molten section extending from the connection between the bottom and vertical surfaces of the fins to the center of the fins is formed. The extension to the center of the bottom and vertical surfaces of the fins can effectively expand the contact area between the second molten section and the bottom and vertical surfaces of the fins, as well as the heat transfer base surface, and can effectively expand the area of ​​heat transfer from the heat transfer base surface. At the same time, the connection strength between the fins and the heat transfer base surface is improved.

[0056] In some embodiments, Figures 8 to 11As shown, the fin 13 includes a continuous top surface, a vertical surface 15 and the bottom surface 14, and the adjacent bottom surfaces 14 are arranged in the length direction of the heat transfer base surface at intervals. There is a first gap between the fin bottom surface 14 and the heat transfer base surface 11, wherein the ratio of the fin width to the length of the heat transfer base surface ranges from 1 / 2 to 1 / 2000. Due to the first gap between the fin bottom surface 14 and the heat transfer base surface 11, the heat exchange performance between the two is poor, and it is necessary to increase the ratio of the first melting portion in the fin connecting the fin and the heat transfer base surface. When the fin width is large and the length direction of the heat exchanger base surface is small, the method of the present invention will significantly reduce the overall heat dissipation efficiency of the electric heater due to too many fin bottom surfaces with poor heat transfer efficiency and the length of the first melting portion formed on the side of the fin bottom surface is too short. In multiple embodiments, the ratio range can be 1 / 5; 1 / 8, 1 / 25, 1 / 110, etc., all of which have a high heat exchange effect.

[0057] In some embodiments, high-energy welding is performed only at the contact point between the side edge of the bottom surface of the fin and the heat transfer base surface 11 or the base surface folded edge, thereby reducing the energy consumption of high-energy welding. Figure 3 and Figure 2 In other embodiments, the high energy welding torch works continuously, i.e. Fig.10 and Fig.11 As shown, a second melting part is formed on the heat transfer base surface between the two adjacent fin bottom surfaces, and the second melting part is connected to the first melting part and the second melting section; a second melting part is formed on the base surface fold between the two adjacent fin bottom surfaces, and the second melting part is connected to the first melting part and the second melting section. Compared with the center height of the first melting part, the center of the second melting part is closer to the center of the corresponding fin. Therefore, the first melting part has a better contact area with the fin, further improving the heat dissipation efficiency. At the same time, the heat transfer base surface or the base surface folded edge between the fins is heated and melted by high-energy welding to form liquid molten metal. This part of the molten metal, especially in the case of the second gap between the connection between the vertical surface and the bottom surface of the fin and the base surface, a part of the liquid metal forming the second molten portion is also absorbed into the gap, thereby increasing the heat exchange area of ​​the second molten section, thereby improving the heat exchange efficiency; at the same time, the heat transfer base surface or the base surface folded edge between the fins is heated and melted by high-energy welding to form liquid molten metal. This part of the molten metal, especially in the case of the first gap between the bottom surface of the fin and the base surface, a part of the liquid metal forming the second molten section is also absorbed into the gap, thereby increasing the heat exchange area of ​​the first molten section, thereby improving the heat exchange efficiency.

[0058] In some embodiments, Figures 8 to 11In the invention, corrugated fins are used, which have the advantages of easy purchase and mature technology; when the technical solution of the present invention is adopted, the fins can also be rectangular fins, trapezoidal fins, etc., because the connection structure between the fins and the heat transfer base or the base fold is longer, the length of the bottom side can be effectively increased, thereby increasing the length of the first melting part, which is beneficial to improving the heat dissipation efficiency. Moreover, punching seams can be formed on the vertical surface of the fins, which is beneficial to improving the heat exchange on the air side.

[0059] In some embodiments, Figure 8 and Fig. 9 The lower part of the fin side forms a fin melt loss area. The formation of the melt loss area is due to the fact that in order to form more molten metal liquid and keep the liquid molten metal for a longer time during high-energy welding, taking laser welding as an example, the irradiation point of the laser welding gun will reciprocate, that is, a laser irradiation area of ​​a certain width is formed to increase the volume of the molten metal liquid and keep it in liquid state for a longer time so that the molten metal liquid can penetrate and expand. The upper edge of the fin melt loss area is spaced H from the lower edge of the fin bottom surface, and the spacing is 1 / 5-1 / 80 times the fin height; the melt loss distance of the fin side surface is 0.2 to 5mm; the lower part of the fin vertical side is welded to the first molten part, and the connecting surface is a curved surface, which protrudes toward the center of the fin. There are some melt losses through the vertical surface and the bottom surface of the lower side of the fin. Although some heat transfer area to the vertical surface of the fin is sacrificed, it is not adopted by technical personnel in this field. However, in the technical solution disclosed in the present invention, the melt loss area at the lower part of the side of the vertical surface of the fin can increase the volume of the molten metal liquid to a certain extent, thereby increasing the contact area between the first melting part, the first melting section and the second melting section and the bottom surface of the fin, or the side of the vertical surface; and the melt loss area at the lower part of the side of the vertical surface of the fin can increase the volume of the molten metal liquid to a certain extent, thereby increasing the contact area between the first melting part, the first melting section and the second melting section and the heat transfer base surface or the folded edge of the heat transfer base surface; thereby improving the energy efficiency of heat exchange.

[0060] In some embodiments, Figures 8 to 11 As shown, heat transfer and connection structures such as the first melting portion, the second melting portion, the first melting section, the second melting section, etc. in the above embodiment are formed between the two sides of the fins of the electric heater and the heat transfer base surface / the base surface folding edge. Figures 8 to 11 The heat dissipation housing includes an upper heat transfer base surface or base surface folding edge, and also includes a lower heat transfer base surface or base surface folding edge, and the lower heat transfer base surface or base surface folding edge thereof also forms heat transfer and connection structures such as the first melting portion, the second melting portion, the first melting section, the second melting section, etc. in the above-mentioned embodiments. That is, multiple heat transfer base surfaces and / or heat transfer base surface folding edges form the heat transfer and connection structures disclosed above.

[0061] The present invention also discloses an air heater, including the electric heater as in the above embodiment, wherein the fins 13 are used to exchange heat with the air, and the heat transfer base surface 11 is surrounded by a receiving cavity 24 for arranging a PTC electric heating core. Figure 7 As shown, further, the upper and lower parts of the PTC electric heating core in the accommodating cavity 24 are provided with electrode sheets, and insulating paper is wrapped outside the electrode sheets, and the power supply supplies power to the PTC electric heating core through the electrode sheets. And the heating capacity of the PTC electric heating core corresponding to the upper and lower heat transfer base surfaces at the left and right sides of the accommodating cavity 24 is greater than the heating capacity of the PTC heating core corresponding to the middle area of ​​the heat dissipation substrate. Due to the use of the heat dissipation structure disclosed in the present invention, the heat dissipation capacity of the upper and lower heat transfer base surfaces at the left and right sides of the heat dissipation housing is the strongest, so when there is a large heating capacity here, it can also be well dissipated. There is a gap between the middle area of ​​the heat dissipation substrate and the corresponding fins and base surfaces, and the heat dissipation is poor, reducing the heating capacity of the corresponding PTC electric heating core, which can avoid local high temperature and affect the reliability of the air heater. In the description of this specification, the description of the reference terms "first embodiment", "second embodiment", "example", etc. means that the specific method, device or feature described in conjunction with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, methods, devices or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without contradicting each other.

[0062] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A heat transfer component, comprising a heat transfer substrate, characterized in that: It also includes a fin, which has a bottom surface close to the heat transfer substrate and a vertical surface connected to the bottom surface; the heat transfer substrate includes a heat transfer base surface, wherein the bottom surface side edge of the fin is close to the heat transfer base surface, and a first melting portion connecting the bottom surface side edge and the heat transfer base surface is formed at the junction of the bottom surface side edge of the fin and the heat transfer base surface; The first melting portion is welded to the heat transfer base surface, the first melting portion extends along the length direction of the joint, a first melting section is formed between the bottom surface at the side of the fin and the heat transfer base surface, the first melting section is connected to the first melting portion, and the first melting section is welded to the heat transfer base surface, or / and the first melting section is welded to the fin; the first melting section extends toward the center of the bottom surface; The heat transfer between the heat transfer base surface and the fin is mainly achieved by connecting the heat transfer base surface and the fin bottom surface through the first fusion portion and strengthening the heat transfer. There is a gap between the remaining part of the fin bottom surface and the heat transfer base surface, and the heat transfer capacity is relatively small.

2. The heat transfer assembly according to claim 1, characterized in that: There is a second gap between the connection between the bottom surface of the fin and the vertical surface of the fin and the heat transfer base surface. A second melting section connected to the first melting part is formed at the connection point of the fins. The second melting section is welded to the heat transfer base surface, or / and the second melting section is welded to the fin; the second melting section extends toward the center of the bottom surface.

3. The heat transfer assembly according to claim 1, characterized in that: The heat transfer substrate also has a base folded edge, the bottom side of the fin is close to the base folded edge, and a first melting portion connecting the bottom side and the heat transfer base folded edge is formed at the junction of the bottom side of the fin and the heat transfer base folded edge; the fin includes a continuous top surface, a vertical surface and the bottom surface, and adjacent bottom surfaces are arranged at intervals along the length direction of the heat transfer base surface; a second melting portion is formed on the heat transfer base surface between two adjacent fin bottom surfaces, and the second melting portion is connected to the first melting portion.

4. The heat transfer assembly according to claim 1, characterized in that: The lower part of the fin side forms a fin melt loss area, and the upper edge formed by the fin melt loss area is spaced H from the lower edge of the fin side surface, and the spacing is 1 / 5-1 / 80 times the fin height; the melt loss distance of the fin side surface is 0.2 to 5mm; the lower part of the side of the fin vertical surface is welded to the first molten part, and the connecting surface is a curved surface, which protrudes toward the center of the fin.

5. A gas-liquid fluid heat exchange component, comprising a heat exchange shell, the heat exchange shell forming a liquid flow channel, and at least one side of the heat exchange shell forming a heat transfer component as claimed in any one of claims 1 to 4, characterized in that: The heat exchange shell forms a flat liquid flow channel, and the liquid flowing in the liquid flow channel is one or more of a supercooled liquid, a saturated liquid or a gas-liquid mixture.

6. The gas-liquid fluid heat exchange assembly according to claim 5, characterized in that: The flat flow channel is divided into multiple small flow channels by multiple partitions; the heat exchange efficiency of the inner wall of the liquid flow channel is different, and the heat exchange efficiency of the upper and lower inner wall surfaces on both sides is higher than that of the inner wall surface of the horizontal part of the shell; the outer surface of the heat exchange shell forms a heat transfer base surface, and the heat transfer base surface is a plane or a curved surface; the vertical surface of the base fold of the heat transfer base surface and the connection with the heat transfer base surface have a thickened convex edge; the first melting part corresponds to one side of the heat exchange base surface, and the corresponding flow channel is a one side flow channel; the unit width flow area of ​​the one side flow channel is greater than the unit width flow area of ​​the middle flow channel; the inner wall surface of the one side flow channel has a heat exchange enhancement structure, and the heat exchange enhancement structure is an internal tooth structure or an inclined internal thread structure.

7. A parallel flow heat exchanger, comprising the gas-liquid fluid heat exchange component as described in claim 5, characterized in that: the flat liquid flow channel formed by the heat exchange shell, a plurality of the flat liquid flow channels are arranged in an interval, the fins are arranged on both sides of adjacent flat liquid flow channels, and at least one end of the flat liquid flow channel is connected to a collecting pipe; the top surface of the fin is in contact with the shell of the flat liquid flow channel located thereon, and the side edge of the top surface of the fin is close to the heat transfer base surface of the bottom surface of the shell, and a first melting portion connecting the side edge of the top surface and the heat transfer base surface of the bottom surface of the shell is formed at the close joint.

8. An air heater, comprising a heat dissipation housing, and a heating core disposed in the heat dissipation housing, wherein at least one side of the heat dissipation housing is formed with a heat transfer component as claimed in any one of claims 1 to 4, characterized in that: The fins are used for exchanging heat with the air, and the heat transfer base surface forms a receiving cavity for arranging the PTC electric heating core.

9. The air heater according to claim 8, characterized in that: The PTC electric heating core in the accommodating cavity is provided with electrode sheets above and below, and insulating paper is provided outside the electrode sheets. The power supply supplies power to the PTC electric heating core through the electrode sheets; the heating capacity of the PTC electric heating core corresponding to the upper and lower heat transfer base surfaces at the left and right sides of the accommodating cavity is greater than the heating capacity of the PTC electric heating core corresponding to the middle area of ​​the heat dissipation substrate.

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