Large-size solar heat collector with adjustable flow resistance

Abstract

The invention provides a large-size solar heat collector with adjustable flow resistance, belongs to the technical field of solar photo-thermal utilization, and aims to solve the problem of low photo-thermal efficiency caused by resistance imbalance and non-uniform liquid separation caused by parallel connection of large-size runners in the prior art. Comprising a heat collector body, a plurality of micro-channel flat pipes, an upper collecting pipe, a lower collecting pipe and an adjusting assembly, and the plurality of micro-channel flat pipes are arranged in the heat collector body at equal intervals in the length direction of the heat collector body; the upper collecting pipe and the lower collecting pipe are respectively communicated with two ends of the micro-channel flat pipe; the adjusting assembly is arranged in the heat collector body and used for adjusting the area of the cross section of each micro-channel flat pipe. According to the solar heat collector, the adjusting assembly can adjust the area of the cross section of each micro-channel flat pipe, so that the flow resistance of liquid flowing through the micro-channel flat pipes can be adjusted, and the overall flow resistance adjustment and performance of the solar heat collector are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of solar thermal utilization, and in particular relates to a large-size solar thermal collector with adjustable flow resistance. Background Art

[0002] Building energy consumption accounts for 22% of the total social energy consumption. Striving to reduce building carbon emissions is an important measure. Using solar energy to provide hot water and heating for buildings has great development potential. The use of solar energy is not only restricted by the local solar energy resources, but also by the development level of solar thermal technology.

[0003] Solar thermal utilization technology mostly uses solar collectors for collection and conversion. In order to facilitate the integrated application of solar buildings, most solar collectors currently have a collection area of ​​1m 2 -2m 2 The series and parallel connection of multiple collectors will reduce the effective collection area, and multiple interfaces will cause leakage and additional heat loss. Therefore, large-size flat-plate collectors (effective area>10m 2 ) can effectively solve the above problems.

[0004] In order to complete the above tasks, a variety of solutions have been proposed in the prior art. For example, a large-size flat-plate solar collector (CN201420590489.8) and a new large-size PVT collector (CN201910282199.4) use copper tubes and heat-absorbing plates to weld to form a large-size heat-absorbing plate core, reducing the frame area and heat loss; an integrally coated high-efficiency plate-type solar collector (201821102111.3) uses microchannel flat tubes as heat collection / heat transfer channels to reduce the thermal resistance caused by welding. However, the above designs all ignore the unbalanced resistance and uneven liquid distribution caused by the parallel connection of large-size flow channels, which leads to the problem of low photothermal efficiency. Summary of the invention

[0005] In view of this, the present invention provides a large-sized solar collector with adjustable flow resistance to solve the problem in the prior art that the resistance imbalance and uneven liquid distribution caused by parallel connection of large-sized flow channels are ignored, resulting in low photothermal efficiency.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A large-size solar thermal collector with adjustable flow resistance, comprising:

[0008] Collector body;

[0009] Microchannel flat tubes, the microchannel flat tubes are in plurality, and the plurality of microchannel flat tubes are arranged in the collector body at equal intervals along the length direction of the collector body;

[0010] An upper header and a lower header, wherein the upper header and the lower header are respectively connected to two ends of the microchannel flat tube;

[0011] The regulating component is arranged in the collector body and is used to adjust the cross-sectional area of ​​each microchannel flat tube.

[0012] In this technical solution, it should be noted that the upper and lower collecting pipes are existing technologies, and their function is to provide a general channel. No further explanation will be given here. The walls of the upper and lower collecting pipes are provided with welding holes of the same size and equal spacing for connecting with the microchannel flat tubes. The upper and lower ends of the microchannel flat tubes are respectively connected with the welding holes of the lower and upper collecting pipes and welded and fixed; in this solution, the adjustment component can adjust the cross-sectional area of ​​each microchannel flat tube, so that the flow resistance of the liquid flowing through the microchannel flat tube can be adjusted, so that the overall flow resistance of the solar collector can be adjusted and the performance can be improved. Therefore, the present invention achieves the technical effect of structural optimization and improved photothermal efficiency.

[0013] Preferably, each of the microchannel flat tubes includes a plurality of microfluidic holes, and the regulating assembly includes a closing block, and the closing block is used to close the microfluidic holes.

[0014] In this technical solution, it should be noted that the microchannel flat tube is a flat structure having a number of separated channels, that is, a number of microfluidic holes. The number of microfluidic holes and the hole size are different. In this solution, a closing block is used to adjust the number, size, and position of the microchannel holes in the microchannel flat tube to achieve micro-resistance regulation, and ultimately complete the overall flow resistance regulation and performance improvement of the large-size solar collector.

[0015] Preferably, fins are respectively provided on both wings of the microchannel flat tube, and the surfaces of the microchannel flat tube and the fins have a heat absorbing coating.

[0016] In this technical solution, it should be noted that fins are usually formed by adding metal sheets with strong thermal conductivity to the surface of a heat exchange device where heat transfer is required, so as to increase the heat exchange surface area of ​​the heat exchange device.

[0017] Preferably, a plurality of microchannel flat tubes are arranged at equal intervals.

[0018] Preferably, the distance between two adjacent microchannel flat tubes is 45-50 mm.

[0019] Preferably, the edges of two adjacent fins overlap each other, and the overlapping width is 3-5 mm.

[0020] Preferably, the collector body comprises a bottom plate, the bottom plate is provided with a frame around it, and a transparent glass cover is provided on the top of the frame.

[0021] Preferably, an air insulation layer is provided between the transparent glass cover plate and the microchannel flat tubes.

[0022] Preferably, the microchannel flat tubes, the frame and the bottom plate are filled with heat-insulating materials.

[0023] Preferably, the area of ​​the collector body is 10m 2 -20m 2 , width is 2m, length is 5-10m, thickness is 140mm, the thickness of the air layer is 30mm, and the thickness of the thermal insulation material is 80mm.

[0024] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0025] 1. In the present invention, the regulating component can adjust the cross-sectional area of ​​each microchannel flat tube, thereby adjusting the flow resistance of the liquid flowing through the microchannel flat tube, so that the overall flow resistance of the solar collector can be adjusted and the performance can be improved;

[0026] 2. In the present invention, a closing block is used to adjust the number, size, and position of the microchannel flat tube microchannel holes to achieve micro-resistance control, and ultimately complete the overall flow resistance adjustment and performance improvement of the large-size solar collector. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] The present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0029] Figure 1 is a schematic structural diagram of a large-size solar thermal collector with adjustable flow resistance disclosed in an embodiment of the present application at a first viewing angle;

[0030] Figure 2 is a schematic structural diagram of a large-size solar thermal collector with adjustable flow resistance disclosed in an embodiment of the present application at a second viewing angle;

[0031] Figure 3 It is a schematic diagram of the structure of the fin microchannel heat collection flat tube disclosed in the embodiment of the present application;

[0032] Wherein: 1-transparent glass cover, 2-air insulation layer, 31-fin, 32-microchannel flat tube, 33-microchannel hole, 34-closing block, 35-lower header, 36-upper header, 4-insulation material, 5-frame, 6-bottom plate. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0036] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0037] In addition, the terms "installed", "set", "provided with", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0039] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0040] Example

[0041] like Figure 1-Figure 3 As shown, an embodiment of the present invention discloses a large-size solar thermal collector with adjustable flow resistance, comprising:

[0042] Collector body;

[0043] Microchannel flat tubes 32, there are a plurality of microchannel flat tubes 32, and the plurality of microchannel flat tubes 32 are arranged in the collector body at equal intervals along the length direction of the collector body;

[0044] An upper header 36 and a lower header 35, wherein the upper header 36 and the lower header 35 are respectively connected to two ends of the microchannel flat tube 32;

[0045] The regulating component is arranged in the collector body and is used to adjust the cross-sectional area of ​​each micro-channel flat tube 32 .

[0046] It should be noted that the walls of the upper manifold 36 and the lower manifold 35 are provided with welding holes of the same size and equal spacing for communicating with the microchannel flat tubes 32. The upper and lower ends of the microchannel flat tubes 32 are respectively connected to the welding holes of the lower manifold 35 and the upper manifold 36 and welded and fixed; in this solution, the adjustment component can adjust the cross-sectional area of ​​each microchannel flat tube 32, so that the flow resistance of the liquid flowing through the microchannel flat tube 32 can be adjusted, so that the overall flow resistance of the solar collector can be adjusted and the performance can be improved, so the present invention achieves the technical effect of structural optimization and improved photothermal efficiency.

[0047] like Figure 2 and Figure 3 As shown, in this embodiment, each of the microchannel flat tubes 32 includes a plurality of microchannel holes 33, and the regulating assembly includes a closing block 34, and the closing block 34 is used to close the microchannel hole 33. It should be noted that the microchannel flat tube 32 is a flat structure, which has a plurality of separated channels, that is, a plurality of microchannel holes 33, and the number and size of the microchannel holes 33 are different. In this solution, the closing block 34 is used to adjust the number, size, and position of the microchannel holes 33 of the microchannel flat tube 32 to achieve micro-resistance regulation (similar to plugging the hole with a plug), and finally complete the overall flow resistance regulation and performance improvement of the large-size solar collector.

[0048] like Figure 2 and Figure 3 As shown, in this embodiment, the two wings of the microchannel flat tube 32 are respectively provided with fins 31, and the surfaces of the microchannel flat tube 32 and the fins 31 have a heat absorbing coating. It should be noted that the fins 31 are usually added to the surface of the heat exchange device where heat transfer is required by adding a metal sheet with strong thermal conductivity to increase the heat exchange surface area of ​​the heat exchange device.

[0049] like Figure 2 As shown, in this embodiment, a plurality of microchannel flat tubes 32 are arranged at equal intervals.

[0050] In this embodiment, the distance between two adjacent microchannel flat tubes 32 is 45-50 mm.

[0051] In this embodiment, the edges of two adjacent fins 31 overlap each other, and the overlapping width is 3-5 mm.

[0052] like Figure 2 As shown, in this embodiment, the collector body includes a bottom plate 6 , a frame 5 is provided around the bottom plate 6 , and a transparent glass cover plate 1 is provided on the top of the frame 5 .

[0053] like Figure 2 As shown, in this embodiment, an air insulation layer 2 is provided between the transparent glass cover plate 1 and the microchannel flat tube 32 .

[0054] like Figure 2 As shown, in this embodiment, the space between the microchannel flat tube 32 and the frame 5 and the bottom plate 6 is filled with a heat-insulating material 4 .

[0055] In this embodiment, the area range of the collector body is 10m 2 -20m 2 , width is 2m, length is 5-10m, thickness is 140mm, thickness of the air layer is 30mm, thickness of the thermal insulation material 4 is 80mm.

[0056] The circuits, electronic components and modules involved are all prior art and can be fully implemented by those skilled in the art. Needless to say, the content protected by the present invention does not involve improvements to software and methods.

[0057] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0058] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A large-size solar collector with adjustable flow resistance, characterized in that: include: Collector body; A plurality of microchannel flat tubes (32) are provided in the heat collector body at equal intervals along the length direction of the heat collector body; An upper header (36) and a lower header (35), wherein the upper header (36) and the lower header (35) are respectively connected to two ends of the microchannel flat tube (32); An adjustment component is arranged in the collector body and is used to adjust the cross-sectional area of ​​each microchannel flat tube (32).

2. A large-size solar thermal collector with adjustable flow resistance according to claim 1, characterized in that: Each of the microchannel flat tubes (32) includes a plurality of microchannel holes (33), and the regulating component includes a closing block (34), and the closing block (34) is used to close the microchannel holes (33).

3. A large-size solar thermal collector with adjustable flow resistance according to claim 1, characterized in that: The two wings of the microchannel flat tube (32) are respectively provided with fins (31), and the surfaces of the microchannel flat tube (32) and the fins (31) have a heat absorbing coating.

4. A large-size solar thermal collector with adjustable flow resistance according to claim 3, characterized in that: A plurality of microchannel flat tubes (32) are arranged at equal intervals.

5. A large-size solar thermal collector with adjustable flow resistance according to claim 4, characterized in that: The distance between two adjacent microchannel flat tubes (32) is 45-50 mm.

6. A large-size solar thermal collector with adjustable flow resistance according to claim 4, characterized in that: The edges of two adjacent fins (31) are overlapped with each other, and the overlap width is 3-5 mm.

7. A large-size solar thermal collector with adjustable flow resistance according to claim 1, characterized in that: The heat collector body comprises a bottom plate (6), a frame (5) is arranged around the bottom plate (6), and a transparent glass cover plate (1) is arranged on the top of the frame (5).

8. A large-size solar thermal collector with adjustable flow resistance according to claim 7, characterized in that: An air heat insulation layer (2) is provided between the transparent glass cover plate (1) and the microchannel flat tube (32).

9. A large-size solar thermal collector with adjustable flow resistance according to claim 8, characterized in that: The space between the microchannel flat tube (32) and the frame (5) and the bottom plate (6) is filled with a heat-insulating material (4).

10. A large-size solar thermal collector with adjustable flow resistance according to claim 9, characterized in that: The area of ​​the collector body is 10m 2 -20m 2 , width is 2m, length is 5-10m, thickness is 140mm, thickness of the air layer is 30mm, thickness of the thermal insulation material (4) is 80mm.

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