Single-channel flow heat exchange test piece for printed circuit board type heat exchanger

Abstract

The invention provides a single-channel flow heat exchange test piece for a printed circuit board heat exchanger, and belongs to the field of heat exchanger research and design. The problem that in the prior art, a PCHE core cannot meet the research requirements for diversity and flexibility of different working conditions and different runner types is solved. The invention relates to a metal plate, which comprises a metal plate, steel plates and a medium flow channel, the medium flow channel is arranged at the center of the metal plate, the upper end and the lower end of the metal plate are respectively provided with six steel plates, the diameter of the medium flow channel is 1-2mm, the thickness of the steel plates is 1mm, the thickness of the metal plate is 3mm, the width of the steel plates and the metal plate is 15mm, and the length of the steel plates and the metal plate is 500mm. Five round holes with the diameter of 0.5 mm are evenly formed in every two adjacent steel plates from the interval of 0-200 mm, nine round holes with the diameter of 0.5 mm are evenly formed in the interval of 200-300 mm, and five round holes with the diameter of 0.5 mm are evenly formed in the interval of 300-500 mm. The device is mainly used for heat exchanger research.

Description

Technical Field

[0001] The invention belongs to the field of heat exchanger research and design, and in particular relates to a single-channel flow heat exchange test piece of a printed circuit board type heat exchanger. Background Art

[0002] Printed circuit board heat exchangers have a wide range of applications, including solar thermal power generation, natural gas transportation, hydrogen liquefaction precooling, nuclear industry and other fields. PCHE has a small structure, a larger heat exchange area, and a lighter weight compared to traditional heat exchangers. It is resistant to high temperature and high pressure, low temperature and corrosion. It is widely used in many heat transfer equipment and systems. The heat exchange core is the core component of PCHE. It is made of metal plates etched with medium flow channels and then stacked and diffused. The application scenario of the present invention is experimental use. The PCHE core in the laboratory environment pays more attention to the flexibility and diversity of the experiment, rather than the compactness and high efficiency in large-scale commercial production. There is no need for dense arrangement. The PCHE core in the laboratory needs to be customized according to different experimental needs, including the design of the flow channel type and the structure of the PCHE assembly, etc., to adapt to different experimental conditions and test purposes. However, the PCHE core in the prior art cannot meet the research needs for different working conditions and the diversity and flexibility of different flow channel types. Summary of the invention

[0003] In view of this, the present invention aims to propose a printed circuit board type heat exchanger single-channel flow heat exchange test piece to solve the problem that the PCHE core in the prior art cannot meet the research requirements for diversity and flexibility of different working conditions and different flow channel types.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A single-channel flow heat exchange test piece comprises a metal plate, a steel plate and a medium flow channel. The center of the metal plate is provided with a medium flow channel, and six steel plates are installed at both upper and lower ends of the metal plate.

[0006] Furthermore, the medium flow channel has a diameter of 1-2 mm.

[0007] Furthermore, the thickness of the steel plate is 1 mm, the thickness of the metal plate is 3 mm, the width of the steel plate and the metal plate is 15 mm, and the length of the steel plate and the metal plate is 500 mm.

[0008] Furthermore, each of the two adjacent steel plates has 5 circular holes with a diameter of 0.5 mm evenly arranged in the range of 0-200 mm, 9 circular holes with a diameter of 0.5 mm evenly arranged in the range of 200-300 mm, and 5 circular holes with a diameter of 0.5 mm evenly arranged in the range of 300-500 mm.

[0009] Furthermore, the medium flow channel is a straight channel, an S-shaped channel or a Zigzag-shaped channel.

[0010] Furthermore, the single-channel flow heat exchange test piece is applied to the core of a printed circuit board type heat exchanger.

[0011] Furthermore, it also includes a heating layer, a thermocouple and a joint. The thermocouple is wound around the outside of the core, the outside of the thermocouple is the heating layer, and the thermocouple is connected to the joint.

[0012] Furthermore, a heat-insulating layer is provided on the outside of the heating layer.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] The present invention aims to manufacture a PCHE core for laboratory use, which can meet the research needs of diversity and flexibility of different working conditions and different flow channel types, reveal the influence of different flow channels on fluid flow and heat transfer, find the best manifold and boundary conditions to achieve the best heat exchange effect, and provide practical guidance and scientific basis for the commercial design and manufacture of PCHE through the accumulation and analysis of experimental data. For commercial PCHE cores, the channels are arranged closely, and the thermal hydraulic properties in a single channel cannot be studied. The channel spacing is too small to effectively cut out a single channel. The PCHE microchannels in the experimental environment are required to be wider, and the spacing between the flow channels is required to be larger, so that the core can be cut into a single channel for convenient experimental use. In addition, a part on which a measuring device can be installed is designed. Compared with the commercial PCHE core that can only measure the inlet and outlet temperatures, the real-time temperature of the flow channels in different areas can also be monitored, making the experimental data more specific and accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0016] Figure 1 A perspective view of a single-channel flow heat exchange test piece according to the present invention;

[0017] Figure 2 It is a structural schematic diagram of a single-channel flow heat exchange test piece according to the present invention;

[0018] Figure 3 It is a structural schematic diagram of the steel plate;

[0019] Figure 4 is a schematic diagram of a straight channel;

[0020] Figure 5 It is a schematic diagram of S-shaped access;

[0021] Figure 6 It is a schematic diagram of a Zigzag channel;

[0022] Figure 7 A schematic diagram of the interior of a printed circuit board heat exchanger.

[0023] 1-metal plate, 2-steel plate, 3-medium flow channel, 4-core, 5-heating layer, 6-thermocouple, 7-insulation layer, 8-joint. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely explain the technical solutions in the embodiments of the present invention. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict, and the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0025] See also Figure 1-7 To illustrate the present embodiment, a single-channel flow heat exchange test piece of a printed circuit board type heat exchanger includes a metal plate 1, a steel plate 2 and a medium flow channel 3. The medium flow channel 3 is opened at the center of the metal plate 1, and 6 steel plates 2 are installed at the upper and lower ends of the metal plate 1. The diameter of the medium flow channel 3 is 1-2mm, the thickness of the steel plate 2 is 1mm, the thickness of the metal plate 1 is 3mm, the width of the steel plate 2 and the metal plate 1 are both 15mm, and the length is both 500mm. The medium flow channel 3 is a straight channel, an S-shaped channel or a Zigzag channel.

[0026] This single-channel flow heat exchange test piece is used in the laboratory to explore the thermal and hydraulic changes of different flow channels and different working fluids in PCHE. The diameter of the fluid channel is generally between 1-2mm. Each core is made of 12 pieces of 1mm thick stainless steel and a 3mm thick metal plate etched with a medium flow channel through diffusion welding. Figure 1 and Figure 2 As shown in the figure, each core has a width of 15mm and a thickness of 15mm, with a total length of 500mm. The test piece adopts a looser channel layout, and the volume occupied by a single flow channel is correspondingly expanded to better adapt to the specific requirements and experimental conditions of the laboratory environment. The single-channel test piece is used to explore the influence of different working fluids and boundary conditions on the heat transfer efficiency of PCHE, as well as the specific role of different flow channel types on heat transfer performance. The single-channel PCHE not only provides an experimental basis for the optimization of the heat transfer performance of PCHE, but also provides an in-depth understanding and prediction of the heat transfer characteristics of different working fluids in practical applications, enhances the understanding of the heat transfer performance of PCHE heat exchangers under different operating conditions, and provides scientific design guidance for industrial applications.

[0027] Moreover, the test piece can meet the research needs for diversity and flexibility of different working conditions and different flow channel types, reveal the influence of different flow channels on fluid flow and heat transfer, find the best manifold and boundary conditions to achieve the best heat exchange effect, and provide practical guidance and scientific basis for the commercial design and manufacture of PCHE through the accumulation and analysis of experimental data. For the commercial PCHE core, the channels are arranged closely, and the thermal-hydraulic properties in a single channel cannot be studied. The channel spacing is too small to effectively cut out a single channel. The PCHE microchannels in the experimental environment are required to be wider and the spacing between the flow channels is required to be larger so that the core 4 can be cut into a single channel for easy experimental use. A part on which measuring equipment can be installed is designed. Compared with the commercial PCHE core that can only measure the inlet and outlet temperatures, the real-time temperature of the flow channels in different areas can also be monitored, making the experimental data more specific and accurate.

[0028] Furthermore, five circular holes with a diameter of 0.5 mm are evenly arranged in the interval of 0-200 mm between each two adjacent steel plates 2, nine circular holes with a diameter of 0.5 mm are evenly arranged in the interval of 200-300 mm, and five circular holes with a diameter of 0.5 mm are evenly arranged in the interval of 300-500 mm. The circular holes are used to install small thermocouples or temperature sensors for experimental measurement of flow channel temperature.

[0029] In order to install a 0.5mm round hole, we need to open a semicircular hole groove with a diameter of 0.5mm on each added steel plate, and put the two steel plates together to form a round hole with a diameter of 0.5mm. Figure 3 As shown. The circular hole is required to be able to form a gap with a 0.5mm circular thermocouple. Each etched plate is welded together with 12 1mm thick steel plates by diffusion welding. Each two steel plates are buckled together in six groups. There are 19 0.5mm circular holes between each group of steel plates for installing measuring equipment.

[0030] Furthermore, in order to meet different fluid channel types, a straight channel, an S-shaped channel or a Zigzag-shaped channel can be processed.

[0031] The single-channel flow heat exchange test piece is applied to the core 4 of the printed circuit board type heat exchanger. The printed circuit board type heat exchanger also includes a heating layer 5, a thermocouple 6 and a joint 8. The thermocouple 6 is wrapped around the outside of the core 4. The outside of the thermocouple 6 is the heating layer 5. The thermocouple 6 is connected to the joint 8. The outside of the heating layer 5 is provided with an insulation layer 7.

[0032] First, the chemical etching method is used to etch out the required flow channels, and to ensure that the flow channels are smooth and free of barbs or other factors that affect the flow of the fluid. Each type of flow channel is etched to ensure that the distance between the two flow channels is 15mm, which is conducive to wire cutting out a single channel. The etched flow channel plate is then diffusely welded to 6 groups of 2mm thick steel plates, three groups on the upper and lower sides of the etched plate, each group is composed of two 1mm thick steel plates buckled together, and each group has 19 circular holes with a diameter of 0.5mm for installing the measuring device. The matching relationship between the circular holes and the measuring equipment is preferably a clearance fit. The final assembly is completed as shown in the figure. Figure 7 As shown, the outermost part is insulated with thermal insulation materials, and the second part is the heating part. The electric heating wire is tightly wound around the core surface to make it evenly heated and convenient to heat. The core is composed of 4 parts of the core. There is a 0.5mm diameter round hole on the non-flow channel side of the core to embed the measuring equipment to connect the computer to observe the fluid temperature. Secondly, the fluid pipelines are welded at the inlet and outlet to facilitate the introduction and export of the fluid into the channel.

[0033] The working method is to guide the working fluid from the cylinder to the pipe welded on the core 4 and enter the core 4, turn on the heating switch, use a multimeter to measure the current, voltage, and resistance, calculate the Joule heat, and calculate the heating power to obtain the wall heat flux density from the surface to the flow channel. When the thermoelectric 6 monitors that the flow channel temperature is unchanged, the experimental data is recorded, and other physical quantities at the inlet and outlet such as flow rate, inlet and outlet temperature, pressure, etc. are detected at the same time to facilitate researchers' research and summary, change a working fluid, channel type or boundary conditions, etc., repeat the above operations to obtain experimental data, and record them.

[0034] The embodiments of the present invention disclosed above are only used to help illustrate the present invention. The embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. According to the content of this specification, many modifications and changes can be made. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well.

Claims

1. A single-channel flow heat exchange test piece of a printed circuit board type heat exchanger, characterized in that: It comprises a metal plate (1), a steel plate (2) and a medium flow channel (3); the medium flow channel (3) is opened at the center of the metal plate (1), and six steel plates (2) are installed at the upper and lower ends of the metal plate (1).

2. A printed circuit board type heat exchanger single-channel flow heat exchange test piece according to claim 1, characterized in that: The medium flow channel (3) has a diameter of 1-2 mm.

3. A printed circuit board type heat exchanger single-channel flow heat exchange test piece according to claim 1, characterized in that: The thickness of the steel plate (2) is 1 mm, the thickness of the metal plate (1) is 3 mm, the width of the steel plate (2) and the metal plate (1) are both 15 mm, and the length is both 500 mm.

4. A printed circuit board type heat exchanger single-channel flow heat exchange test piece according to claim 3, characterized in that: Every two adjacent steel plates (2) have five circular holes with a diameter of 0.5 mm evenly arranged in the range of 0-200 mm, nine circular holes with a diameter of 0.5 mm evenly arranged in the range of 200-300 mm, and five circular holes with a diameter of 0.5 mm evenly arranged in the range of 300-500 mm.

5. The single-channel flow heat exchange test piece of a printed circuit board type heat exchanger according to claim 1, characterized in that: The medium flow channel (3) is a straight channel, an S-shaped channel or a Zigzag-shaped channel.

6. A printed circuit board type heat exchanger single-channel flow heat exchange test piece according to claim 1, characterized in that: The single-channel flow heat exchange test piece is applied to a core (4) of a printed circuit board type heat exchanger.

7. A printed circuit board type heat exchanger single-channel flow heat exchange test piece according to claim 6, characterized in that: The printed circuit board type heat exchanger also includes a heating layer (5), a thermocouple (6) and a joint (8); the thermocouple (6) is wound around the outside of the core (4); the outside of the thermocouple (6) is the heating layer (5); and the thermocouple (6) is connected to the joint (8).

8. A printed circuit board type heat exchanger single-channel flow heat exchange test piece according to claim 7, characterized in that: A heat-insulating layer (7) is provided outside the heating layer (5).

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