Compact heat exchanger core with fin supporting structure

Abstract

The utility model relates to the technical field of high-temperature and high-pressure heat exchangers, and discloses a compact heat exchanger core with a fin supporting structure, which comprises fins, supporting blocks, a base plate, side plates, etching plates, an upper cover plate and a lower cover plate, the fins, the supporting blocks and the side plates have the same height and are all positioned on the base plate, and the side plates are positioned on two sides of the base plate; a plurality of supporting blocks are arranged between the two side plates at equal intervals, and fins are embedded between every two adjacent supporting blocks and between the side plates and the supporting blocks. The fins, the supporting blocks, the base plate and the side plates form a flow channel structure. The etching surface of the etching plate is provided with a plurality of micro-channels; the etching plates and the flow channel structures are alternately stacked between the upper cover plate and the lower cover plate, and the etching surfaces of the etching plates are in butt joint with the substrate. The utility model solves the problem that the unclean working medium side runner is easy to block, the vertical bearing capacity is increased through the support structure, the loading capacity of the new core body of the heat exchanger is enhanced, and the structure has higher machining efficiency and flexibility.

Description

Technical Field

[0001] The utility model relates to the technical field of high-temperature and high-pressure heat exchangers, in particular to a compact heat exchanger core with a fin support structure. Background Art

[0002] As a kind of high-efficiency compact heat exchanger, a printed circuit board heat exchanger (PCHE) is formed with micro-sized flow channels on the surface of a heat exchange plate through a photochemical etching process. The heat exchange plates on the hot side and the cold side are stacked alternately and welded into a heat exchange core through a diffusion welding process. This kind of heat exchanger has the characteristics of high heat exchange efficiency, compact volume, strong temperature and pressure resistance, etc., and has been applied in the fields of supercritical carbon dioxide power generation, offshore oil and gas, hydrogen energy, aerospace, etc. However, due to factors such as the precision, productivity, and cost of the etching flow channel forming process, the flow channel size of the PCHE is small, and its flow channel diameter is less than 3 mm. In order to avoid blockage of the microchannels by impurity particles and corrosive scaling, it can only be used for heat exchange of working fluids with high cleanliness and low corrosiveness, resulting in limited application scope of the printed circuit board heat exchanger. There is an urgent need for a compact heat exchanger core suitable for heat exchange between corrosive or low-cleanliness working fluids and high-cleanliness and low-corrosive media.

[0003] In order to solve the above problems, patent application CN107782181A and patent CN106403688B disclose a heat exchange core with a combined structure of an etched heat exchange plate, a formed plate, and a partition plate. The formed plate is a stamped rectangular fin, with a larger flow channel size and a low forming process cost, and can be used for working fluids with low cleanliness; however, there are technical deficiencies: limited by the stamping process, the fin thickness is insufficient, the vertical bearing capacity is small, and the fins are prone to deformation or even structural collapse after applying a vertical pressure. Therefore, the pressure applied during the diffusion welding process should not be too large, which reduces the tightness of the diffusion connection, resulting in a decrease in the welding strength of the etched plate and a lower pressure-bearing capacity of the microchannels on the etched plate. Patent CN212482206U discloses a diffusion-welded compact heat exchanger with a combined heat exchange plate. The heat exchange core part is composed of an etched plate and a ribbed plate. The ribbed plate forms a larger-sized flow channel through machining. The ribs can be processed to have sufficient width to ensure a higher pressure-bearing capacity on the ribbed plate side and meet the requirements of diffusion welding; however, there are technical deficiencies: the machining efficiency of the ribbed plate is not high, and a large number of metal ribs are difficult to be integrally processed and formed quickly, resulting in a long processing cycle and difficult to guarantee the machining accuracy of large-sized plates and various-shaped ribs. It is only applicable to the manufacture of small-sized and small-batch heat exchangers, restricting the large-scale application scope of this technical solution. Summary of the Utility Model

[0004] In view of this, the present utility model provides a compact heat exchanger core with a fin support structure, which solves the problem that the non-clean working medium side flow channel is prone to blockage; the vertical bearing capacity is increased through the support structure, and the pressure-bearing capacity of the new heat exchanger core is enhanced; the structure has high machining efficiency and flexibility.

[0005] The present utility model is realized through the following technical solutions: a compact heat exchanger core with a fin support structure includes fins, support blocks, a base plate, side plates, an etched plate, an upper cover plate and a lower cover plate; the fins, support blocks and side plates have the same height and are all located above the base plate; the side plates are located on both sides of the base plate, the side plates and the base plate have the same length along the flow direction, and the edges of the side plates and the base plate are aligned up and down; a number of support blocks are arranged at equal distances between the two side plates, and fins are embedded between two adjacent support blocks and between the side plates and the support blocks; the fins, support blocks, base plate and side plates form a flow channel structure for the flow of non-clean working medium.

[0006] The etched surface of the etched plate has a number of micro-channels for the flow of clean working medium; the etched plate and the flow channel structure are alternately stacked between the upper cover plate and the lower cover plate, and the etched surface of the etched plate is docked with the base plate; the edges of the flow channel structure, the etched plate, the upper cover plate and the lower cover plate are aligned to form a heat exchanger core.

[0007] Preferably, the fin is a U-shaped continuous fin, which is composed of a plurality of U-shaped units arranged in a straight line, and the formed continuous fin is in the form of a square wave or a sine wave or a combination of the two waveforms; or the fin is composed of rectangular metal tubes arranged in a straight line; or the fin is one or more of the above forms.

[0008] Preferably, the support block is a solid metal block with a rectangular cross-section; or the support block is provided with through holes along the flow direction; or the two sides of the support block in contact with the fin are provided with grooves; or the support block is one or more of the above forms; further, the groove is a semi-circular groove or a trapezoidal groove.

[0009] Preferably, a number of cavities are arranged perpendicular to the flow direction in the flow channel structure; further, the fin and the support block are divided into several sections along the flow direction, and the length of each section of the fin and the support block is the same; the same distance is spaced between each section of the fin and between each section of the support block to form the cavity.

[0010] Compared with the existing technology, the beneficial effects of the present utility model are:

[0011] 1. The combination form of the fin flow channel and the etched plate in the utility model effectively solves the problem of easy blockage on the non-clean working medium side; the support block increases the structural strength of the fin flow channel, solves the problem of insufficient vertical bearing capacity of the fins during the diffusion welding process, and greatly enhances the pressure-bearing capacity of the heat exchanger core after welding; the combined structure of the support block and the fins reduces the number of mechanically processed channels, enables the flow channel to be formed with high processing efficiency and flexibility, and can realize the manufacture of large-size and large-batch heat exchangers.

[0012] 2. The side of the support block in the utility model has grooves or through holes, which has the good effects of increasing the heat transfer area, reducing the flow resistance, and reducing the overall weight of the core.

[0013] 3. The U-shaped continuous fins in the utility model can be formed by one-time stamping of a stainless steel thin plate, with high processing efficiency and high precision; the fins, the support block, and the base plate form a non-clean working medium flow channel, and are combined with the etched plate with micro-channels to form a core. The assembly process is simple and there are various assembly methods, which is easy for large-size and batch manufacturing.

[0014] 4. The fins and the support block in the utility model are provided with cavities at regular intervals along the flow direction, which non-continuizes the non-clean working medium flow channel, further reduces the risk of particle impurities blocking the flow channel, and also has the effect of remixing the working medium to achieve uniform temperature and flow rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic cross-sectional view of the utility model.

[0016] Figure 2 is a top view of the flow channel structure.

[0017] Among them, 1 - fin, 2 - support block, 3 - side plate, 4 - base plate, 5 - etched plate, 6 - micro-channel, 7 - lower cover plate, 8 - upper cover plate, 9 - cavity, 201 - semi-circular groove, 202 - through hole, 203 - metal block, 204 - trapezoidal groove. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] In order to make the purpose, technical solutions and advantages of the utility model clearer, the following further details the utility model with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model.

[0019] The utility model provides a compact heat exchanger core with a fin support structure, as Figure 1As shown in the figure, the compact heat exchanger core includes fins 1, support blocks 2, side plates 3, a base plate 4, an etched plate 5, an upper cover plate 8, and a lower cover plate 7; the fins 1, support blocks 2, and side plates 3 have the same height and are all located above the base plate 4; the side plates 3 are located on both sides of the edge of the base plate 4, the side plates 3 and the base plate 4 have the same length along the flow direction, and the edges of the side plates 3 and the base plate 4 are aligned vertically; a number of support blocks 2 are arranged at equal intervals between the two side plates 3, and fins 1 are embedded between two adjacent support blocks 2 and between the side plates 3 and the support blocks 2; the fins 1, support blocks 2, base plate 4, and side plates 3 form a flow channel structure for the flow of non-clean working medium, and this flow channel structure effectively solves the problem of easy blockage on the non-clean working medium side.

[0020] The etched plate 5 is a single-sided etched plate, that is, a number of micro-channels 6 are processed and formed on one side of the etched plate 5 by a photochemical etching process. The etched surface of the etched plate 5 is the side with a number of micro-channels 6, and the micro-channels 6 are used for the flow of clean working medium; the etched plate 5 and the flow channel structure are alternately stacked between the upper cover plate 8 and the lower cover plate 7, and the etched surface of the etched plate 5 is docked with the base plate 4; the edges of the flow channel structure, etched plate 5, upper cover plate 8, and lower cover plate 7 are aligned and connected by diffusion welding to form a heat exchanger core.

[0021] In the present utility model, the support block 2 strengthens the vertical bearing capacity of the flow channel structure, reduces the deformation amount of the fin 1 structure in the diffusion welding process, and a greater pressure can be applied during the diffusion welding process, thereby enhancing the welding tightness, and further improving the pressure-bearing capacity of the micro-channels 6 on the etched plate 5, and enhancing the pressure-resistant capacity of the heat exchanger core.

[0022] In specific implementation, the support block 2 is formed by machining and can be a solid metal block 203 with a rectangular cross-section; or a through hole 202 is provided at the center of the support block 2 along the flow direction; or grooves are provided on both sides of the support block 2 in contact with the fin 1, and the grooves can be semi-circular grooves 201 or trapezoidal grooves 204; or the support block 2 is one or more of the above forms.

[0023] The fin 1 can be a continuous fin in the shape of a "J", which is composed of a number of "J" - shaped units arranged in a straight line and is formed by one-time stamping of a stainless steel thin plate. The continuous fin formed thereby can be in the form of a square wave waveform or a sine waveform or a combination of the two waveforms; or the fin 1 is composed of a straight arrangement and connection of rectangular metal tubes; or the fin 1 is one or more of the above forms.

[0024] As an improvement, as Figure 2As shown in the figure, the flow channel structure is provided with a plurality of cavities 9 perpendicular to the flow direction, so that the fins 1 and the support blocks 2 are divided into several sections along the non-clean working medium flow direction. The lengths of each section of the fins 1 and the support blocks 2 are the same, and the same distance is spaced between each section of the fins 1 and between each section of the support blocks 2 to form the cavities 9. The flow channel structure adopts a discontinuous flow channel design, which further solves the problem that the flow channel on the non-clean working medium side is prone to blockage, and can also achieve the purpose of uniform temperature and flow rate of the non-clean working medium.

[0025] Before diffusion welding, the core body of the present utility model is assembled: In the first step, the assembly of the flow channel structure is completed. The fins 1, the support blocks 2, and the side plates 3 are placed on the substrate 4 with all outer edges aligned, and the contact positions of the fins 1, the support blocks 2, the side plates 3 and the substrate 4 are spot welded by argon arc welding to temporarily fix the relative positions of the components and prevent dislocation. In the second step, a plurality of flow channel structures and a plurality of etched plates 5 are alternately aligned and tightly stacked, and the etched surface of the etched plate 5 is butted against the substrate 4. In the third step, after adding the lower cover plate 7 and the upper cover plate 8, all the components are aligned up and down, and then the components are permanently welded together in a diffusion welding device to form a core body with a reliable structure.

[0026] During the above assembly process, in the first step, the fins 1 and the support blocks 2 can be temporarily fixed first to form a fin assembly, and then the fin assembly is placed in the area temporarily fixed by the side plate 3 and the substrate 4. It is also possible to temporarily fix the support block 2 and the side plate 3 to the substrate 4 first, then embed the fin 1 into the space between the support block 2 and the side plate 3, and then temporarily fix the fin 1 to the support block 2 and the substrate 4. The processing process of the present utility model has high flexibility, is suitable for different working conditions, and has high machining efficiency and high precision, and can realize the manufacture of large-size and large-batch heat exchangers.

[0027] The above are only the preferred embodiments of the present utility model, and are not intended to limit the present utility model. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. A compact heat exchanger core with a fin support structure, characterized in that: It includes fins, support blocks, substrates, side plates, etching plates, upper cover plates and lower cover plates; the fins, support blocks and side plates have the same height and are all located on the substrate; the side plates are located on both sides of the substrate, the side plates and the substrate have the same length along the flow direction, and the edges of the side plates and the substrate are aligned up and down; a number of support blocks are arranged equidistantly between two side plates, and fins are embedded between two adjacent support blocks and between the side plates and the support blocks; the fins, support blocks, substrates and side plates constitute a flow channel structure, and the flow channel structure is used for the flow of non-clean working fluids; The etched surface of the etched plate has a plurality of microchannels, and the microchannels are used for the circulation of clean working fluids; the etched plate and the flow channel structure are alternately stacked between the upper cover plate and the lower cover plate, and the etched surface of the etched plate is butted against the substrate; the flow channel structure, the etched plate, the upper cover plate and the lower cover plate are aligned at their edges to form a heat exchanger core.

2. The compact heat exchanger core according to claim 1, characterized in that: The fins are continuous fins in the shape of an "X", which are composed of multiple "X"-shaped units arranged in a straight line, and the continuous fins formed thereby are in the form of square waves, sinusoidal waves, or a combination of the two waves; or the fins are composed of rectangular metal tubes arranged in a straight line; or the fins are in one or more of the above forms.

3. The compact heat exchanger core according to claim 1, characterized in that: The support block is a solid metal block with a rectangular cross section; or the support block is provided with through holes along the flow direction; or grooves are provided on both sides of the support block contacting the fins; or the support block is one or more of the above forms.

4. The compact heat exchanger core according to claim 3, characterized in that: The groove is a semicircular groove or a trapezoidal groove.

5. The compact heat exchanger core according to any one of claims 1 to 4, characterized in that: The flow channel structure is provided with a plurality of cavities perpendicular to the flow direction.

6. The compact heat exchanger core according to claim 5, characterized in that: The fins and the support blocks are divided into several sections along the flow direction, and each section of the fins and the support blocks has the same length; each section of the fins and each section of the support blocks are spaced at the same distance to form the cavity.

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