KR20170089594A - The heat exchangers using a 3D printer - Google Patents

Abstract

The present invention relates to a heat exchanger using a three-dimensional printer in which a plurality of heat transfer tubes penetrating an upper plate and a lower plate are arranged in a column and a line inside a frame surrounded by the upper plate, the lower plate and both side plates, the heat transfer tubes arranged in the transverse direction are formed of a plurality of branch pipes, which are divided in both directions and joined together, in multiple stages to allow the outside air to pass through the branch pipes, and each adjacent branch pipes of the heat transfer tubes are combined such that objects to be heat-exchanged are spread to each of the heat transfer tubes, thereby expanding the heat dissipation area and enabling the components thereof to be simultaneously formed by electron beam melting (EBM) or selective laser sintering (SLS) printing techniques. To achieve this, the heat exchanger is configured such that a frame having an upper plate, a lower plate and both side plates three-dimensionally printed such that the outside air horizontally passes therethrough is integrally formed; a plurality of heat transfer tubes are three-dimensionally printed in a column and a line inside the frame, and are integrally provided such that upper ends and lower ends thereof penetrate the upper plate and the lower plate to allow the objects to be heat-exchanged to flow therethrough; and the heat transfer tubes are formed of a plurality of branch pipes which are divided in both directions and joined again in multiple stages, and have merging portions to allow portions of the transverse branch pipes in contact with each other to communicate with each other, and are three-dimensionally printed such that the transverse heat transfer tubes are connected into one tube.

Description

[0001] The present invention relates to a heat exchanger using a 3D printer,

[0001] The present invention relates to a heat exchanger for a gas using a 3D printer, and more particularly, to a heat exchanger for a gas using a 3D printer, in which a plurality of heat transfer tubes are arranged in a row and a row by passing through the upper plate and the lower plate inside a frame surrounded by upper and lower plates and side plates The heat transfer tubes are divided into two and joined together to form a multistage so that outside air passes through the center of the branch tubes. The transverse heat transfer tubes are joined to each other so as to be connected to each other, The present invention relates to a heat exchanger using a 3D printer in which an area is enlarged and these components are simultaneously formed by electron beam melting (EBM) or selective laser sintering (SLS) printing techniques.

In general, a plate-type heat exchanger for a gas means a heat exchanger for warming a supply air such as cold air using a hot gas such as waste gas and exhaust gas. The air and the heat-mediated gas to be heated are discharged through a horizontal passage formed by the heat transfer plate material It is a structure that is heat exchanged while intersecting in vertical passage. The plate heat exchanger forms a structure in which the horizontal passage and the vertical passage cross each other by stacking the heat transfer plates. The four corners of the heat transfer plate are portions where the ends of the horizontal passage and the vertical passage face each other. The corner portion is a portion that is opened in a three-dimensional form in which the horizontal passage on the horizontal side intersects with the vertical passage on the vertical side at right angles and is vertically staggered, so it is necessary to prevent the leakage of the gas during heat exchange by blocking the corner portion.

Conventionally, a method of welding a corner sealing means bent at a right angle to the four corners of the heat transfer plate and welding it from the inside of the vertical passage or the horizontal passage was used. Therefore, when the worker inserts the welding rod into the horizontal passage and the vertical passage, the work posture is inconvenient and it is difficult to directly confirm the welding position toward the inside. Especially, in case of a small thin plate having a side passage and a vertical passage of less than 1 mm and a heat transfer plate having a thickness of 0.1 mm to 0.15 mm, it was impossible to seal the corner portion by welding.

The present inventor has proposed a plate heat exchanger in Korean Patent No. 1356474 in order to solve this problem. This has an upper frame and a lower frame provided with a fitting seat for stably fixing the upper and lower ends of the heat transfer plate so that a plurality of small heat transfer plates of the thin flat plates are arranged to repeatedly form transverse passages and vertical passages crossing each other, The pressure and temperature difference prevent the expansion of the heating plate. If the heating plate is inserted into the upper frame and the lower frame, the gap between the horizontal and vertical passages can be kept constant and the fitting seat with the heating plate can be easily welded with brazing or laser .

However, the technique of bending a small thin plate of the heat transfer plate and fixing it by fixing it to the upper and lower frames is difficult to mass-produce because it requires precision. Particularly, when the gas velocity is high, the heat transfer area or heat transfer length should be increased so as not to lower the heat exchange efficiency. However, there is a limit to increase the heat transfer area or length within a limited size.

In recent years, 3D printers are being developed which can be integrally produced even if they are compact and have complicated internal structures. Two well known methods for depositing successive layers to produce a product are Selective Laser Sintering (SLS) and Electron Beam Melting (EBM). All of these methods deposit continuous thin sections of material to produce three-dimensional products. Which involves dispersing a thin layer of the powder on a flat surface. After the layer is dispersed on the surface, a laser or electron beam contacts the selected powder region to fuse these regions. Continuous layers of the powder are dispersed on the preceding layers and a three-dimensional product is made by sintering or fusing by laser or electron beam.

With such a 3D printer, it becomes possible to arrange heat transfer tubes in longitudinal and transverse directions within a frame of a limited size, to connect the heat transfer tubes to each other, and to make the heat transfer tube into a complicated lattice type heat radiation structure, thereby increasing the heat exchange area.

SUMMARY OF THE INVENTION The present invention has been developed in consideration of the conventional problems, and an object of the present invention is to provide a heat exchanger having a plurality of heat transfer tubes passing through the upper plate and the lower plate within a frame surrounded by upper and lower plates and side plates, The heat transfer tubes are divided into two and joined together to form a multistage so that the outside air passes through the center of the branch tubes and the heat transfer tubes in the lateral direction are joined to each other so that the heat transfer tubes are connected to each other, And also to provide a heat exchanger using a 3D printer in which these components are simultaneously formed by electron beam melting (EBM) or selective laser sintering (SLS) printing techniques.

To this end, the present invention is characterized in that a top plate, a bottom plate, and side plates of both sides are 3D-printed and a frame through which the outside air passes horizontally is integrally formed; In the frame, a plurality of heat transfer tubes are printed in a row and a row by a plurality of columns of 3D heat transfer tubes, the upper and lower ends penetrating the upper and lower plates to integrally flow the object to be heat exchanged; The heat transfer tubes are provided with a plurality of branch tubes which are divided into two parts and then joined together in a multi-stage manner, and the horizontal branch tubes are formed by merging sections so that the horizontal heat pipes are connected to one another. have.

According to the present invention, a plurality of small heat transfer tubes having a diameter of about 1 mm are arranged in a row in a row and a row in a row, and the upper and lower ends of the heat transfer tubes pass through the upper and lower plates of the frame. Therefore, the heat exchange objects supplied from the upper plate are simultaneously supplied to the respective heat transfer tubes, and then, the heat transfer objects escape to the lower ends of the respective heat transfer tubes.

The heat transfer tubes arranged in the transverse direction are provided with a plurality of branch pipes which are divided into two parts and joined together, and these branch pipes are formed into a hexagonal shape. In the hexagonal center of each of the branch pipes, a passageway for escaping the outer edge is formed, and heat exchange is performed with the heat exchange object flowing into the heat transfer pipe and the branch pipes. Further, the adjacent branches of the respective heat transfer tubes are combined so that the object to be heat exchanged spreads widely inside the heat transfer tubes.

As a result, the object to be heat exchanged does not pass through each of the heat transfer tubes alone, but the heat transfer area is increased because the passage length is increased while spreading in the zigzag form into the plurality of heat transfer tubes arranged in the transverse direction. In addition, since auxiliary passages through which the outside air passes are formed between the heat transfer tubes arranged in the transverse direction, there is an advantage that heat exchange efficiency is improved.

The framework, heat transfer tubes and branching tubes are formed by selective laser sintering (SLS) or electron beam melting (EBM) printing techniques, in which a thin layer of metal powder is formed on a flat surface and a laser or electron beam By fusing these regions, successive layers of the powder are dispersed on the preceding layers and sintered or fused by a laser, whereby the three-dimensional frame, heat transfer tube and branch tubes are integrally completed and a complicated heat exchanger can be produced rapidly There is an advantage.

1 is an assembled perspective view of a heat exchanger according to an embodiment of the present invention;
Figure 2 is a partial perspective view of a heat exchanger of one embodiment of the present invention;
3 is a front view of a heat exchanger of an embodiment of the present invention;
4 is a partially enlarged section of a heat exchanger of an embodiment of the present invention
5 is a sectional view taken along line A-A in Fig. 3
6 is a sectional view taken along the line B - B in Fig. 3

The heat exchanger of the embodiment of the present invention as shown in FIGS. 1 to 6 is a three-dimensional printed hollow body 10 having a rectangular shape with an upper plate 11, a lower plate 12 and both side plates 13, ) Is a portion where the outside air passes horizontally. A plurality of heat transfer tubes 30 through which the heat exchange object passes vertically is integrally 3D-printed inside the frame 10. The upper and lower ends of the heat transfer tubes 30 are 3D printed so as to pass through the upper plate 11 and the lower plate 12 and connected to the outside of the frame 10. The heat transfer tubes 30 have an inner diameter of about 1 mm, It is 3mm in size, and it is made compact.

The heat transfer tubes 30 are arranged in a row in a row and in a row in a row in the transverse direction of the frame 10. The heat transfer tubes 30 arranged in a transverse direction are divided into a plurality of branch tubes 31 And is provided in multiple stages. These branch pipes 31 are divided into an arcuate shape or a polygonal shape, and the passage 40 is formed by these cracks to allow the outside air to pass through. Preferably, the branches 31 form a shape which is divided into hexagons and merged, and a passage 40 through which the outside air passes is formed at the center of the hexagons. In addition, the branch pipe (31) and the heat transfer pipe (30) are configured to have a hexagonal cross section and have a surface area that is larger than that of the circular pipe.

The heat transfer tubes 30 arranged in the transverse direction have a merging portion 32 in which the adjacent branches 31 are merged into one unit and the transverse heat transfer tubes 30 are connected to each other through the merging portion 32 . Therefore, the heat exchange object flowing into the upper end of the heat transfer tubes 30 in the lateral direction spreads into all of the heat transfer tubes 30 due to the merging portion 32, thereby increasing the heat exchange length. The auxiliary passage 41 is formed by the upper and lower merging portions 32 adjacent to each other of the lateral heat transfer tubes 30. The auxiliary passage 41 is also formed into a hexagonal honeycomb shape.

As a result, the heat transfer tubes 30 in the lateral direction have a hexagonal honeycomb shape with the multi-stage branch tubes 31 merging with the merging section 32, and a honeycomb shape is formed between the center of the branch tubes 31 and the heat transfer tubes 30. [ The hexagonal passage 40 and the auxiliary passage 41 are formed.

The hemispherical upper cover 20 and the lower cover 21 are integrally formed by 3D printing on the upper and lower plates 11 and 12, An inlet space 23 for supplying a heat exchange object to the upper portion of the upper cover 20 and an inlet 22 communicating with the input space portion 23 are formed in the upper cover 20 in a 3D printing process. The lower cover 21 is provided with a discharge space portion 24 communicating with a lower end of the heat transfer tubes 30. An outlet 25 communicating with the discharge space portion 24 is provided in the lower cover 21, . Reference numeral 33 denotes a support for holding the branch pipe 31 adjacent to the side plate 13. [

The frame 10, the covers 20 and 21 and the heat transfer tubes 30 are formed by a selective laser sintering (SLS) or electron beam melting (EBM) printing technique. In the 3D printing process, the frame 10 may be raised or laid down. The operator may determine the efficiency of the 3D printer according to the size of the 3D printer device.

In the case of the 3D printing process, a thin layer of metal powder is formed on a flat surface, and a laser or an electron beam is contacted with a selected powder region to fuse these regions, The layers are dispersed on the preceding layers and sintered / fused by the laser / electron beam. The lower cover 21 is first formed and the lower cover 12, side plate 13, heat transfer tube 30, upper plate 11, (20) in this order to complete a three-dimensional heat exchanger.

The upper and lower ends of the heat transfer tubes 30 communicate with the outside of the upper and lower plates 11 and 12. The upper and lower plates 11 and 12 are provided with an upper cover 20 and a lower cover 21, The object is supplied to the inside of the heat transfer pipe 30. In addition, the transversely arranged portions of the respective heat transfer tubes 30 are formed with multi-stage branch tubes 31, and the adjacent tubes 31 are composed of merging portions 32 communicating with each other. Therefore, all of the heat transfer tubes 30 in the lateral direction are connected to each other to increase the heat transfer length.

The heat exchange process of the embodiment of the present invention will be described. First, an object to be heat-exchanged is introduced into the input space portion 23 through the inlet 22. Since the upper ends of a plurality of heat transfer tubes 30 arranged in a row and a row are connected to the input space portion 23, the object to be heat-exchanged enters the heat transfer tubes 30.

The heat transfer tubes 30 arranged in the transverse direction are connected to each other through the merging portion 32. Therefore, the length of the heat exchange object is increased by passing through the branch pipe (31) and the confluent portion (32), which are introduced into the heat transfer pipes (30) arranged in the transverse direction. Further, a passage 40 and an auxiliary passage 41 are formed between the center of the branch pipe 31 and the heat transfer pipes 30 to allow outside air to pass therethrough. Therefore, the heat exchange object and the outside air intersect with each other to perform heat exchange. Since the heat transfer tubes 30 and the branch tubes 31 have hexagonal cross sections and have increased surface area, the heat exchange performance is improved.

The heat exchange object having passed through each heat transfer pipe 30 is collected in the discharge space portion 24 through the lower end of the heat transfer pipe 30 and then supplied to the next process along the outlet 25 of the lower cover 21.

10: frame 11: top plate
12: lower plate 13: side plate
20: upper cover 21: lower cover
22: inlet 23:
24: exhaust space part 25: outlet
30: heat transfer pipe 31: branch pipe
32: merging section 40: passage
41: auxiliary passage

Claims (4)

A top plate, a bottom plate and side plates of both sides are 3D-printed so that a frame through which the outside air passes horizontally is integrally formed;
In the frame, a plurality of heat transfer tubes are printed in a row and a row by a plurality of columns of 3D heat transfer tubes, the upper and lower ends penetrating the upper and lower plates to integrally flow the object to be heat exchanged;
The heat transfer tubes are divided into a plurality of tubes and a plurality of tubes are joined in multiple stages. The tubes in the transverse direction are 3D-printed so that the portions in contact with each other are connected to each other and the transverse heat transfer tubes are connected to each other. A heat exchanger using a 3D printer. The method according to claim 1,
Wherein the lateral branch pipes are formed in a polygonal shape, a passage through which the outside air passes is formed at the center of the branch pipes,
Wherein the heat transfer tubes in the lateral direction are 3D-printed together with the auxiliary passages through which the outside air passes between the upper and lower merging portions. 3. The method of claim 2,
Wherein the heat transfer tubes and the branch tubes have a hexagonal cross section,
Wherein the branch pipe and the joining portion are integrally 3D-printed so that the passage and the auxiliary passage are hexagonal. 4. The method according to any one of claims 1 to 3,
The 3D printing uses selective laser sintering (SLS) or electron beam melting (EBM) printing,
Wherein a thin layer of metal powder is formed and a laser or an electron beam is contacted with a selected powder region to sinter or fuse these regions.

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