CN211782029U

CN211782029U - Solar vacuum heat collecting tube based on CPC

Info

Publication number: CN211782029U
Application number: CN202020119905.1U
Authority: CN
Inventors: 娄滨; 周园园; 谢维思
Original assignee: Guangzhou Juneng Solar Energy Technology Co ltd
Priority date: 2020-01-19
Filing date: 2020-01-19
Publication date: 2020-10-27
Anticipated expiration: 2030-01-19

Abstract

The embodiment of the application discloses solar vacuum thermal-collecting tube based on CPC includes: the heat absorber comprises a glass tube cover, a heat absorber and a metal tube; the metal tube and the heat absorber are both arranged in the glass tube cover; the number of the heat absorbing bodies is at least three; at least three heat absorbers are arranged on the outer surface of the metal tube at intervals and connected with the metal tube. The utility model discloses an use in the CPC solar panel, can guarantee under the thermal prerequisite of maximum absorption sun, effectively reduce solar vacuum thermal-arrest pipe's manufacturing cost, be a high-quality solar vacuum thermal-arrest pipe based on CPC.

Description

Solar vacuum heat collecting tube based on CPC

Technical Field

The application relates to the technical field of solar radiation transmission, in particular to a solar vacuum heat collecting tube based on a CPC.

Background

Solar energy is increasingly widely used as a clean energy source, wherein the conversion of solar energy into heat energy is the most important application, and the appearance of a Compound Parabolic Concentrator (CPC) directly advances the performance of a solar heat collecting device, so that the non-tracking solar heat collecting device is utilized in the field of medium-high temperature solar energy, and a scene diagram of the solar vacuum heat collecting device in the CPC application is shown in fig. 10.

The solar vacuum heat collecting tube is formed by sealing a receiver by a cylindrical glass tube cover, and the surface of the receiver is attached with a sunlight absorbing coating or a heat absorbing body for quickly collecting sunlight heat. When sunlight irradiates the heat absorber through the glass, the heat absorber absorbs the heat quickly and transfers the heat to the receiver, and then the receiver and an external medium generate heat exchange to finish the work. In order to avoid that the heat collected by the receiver is directly dissipated to the outside of the glass, the space between the glass tube and the receiver is vacuumized, so that the heat collection efficiency is greatly improved, and the tube is called as a solar vacuum heat collection tube for short.

According to the shape division of receiver surface heat-absorbing body, plate receiver and round cast receiver are generally adopted to present current solar vacuum thermal-arrest pipe, but if the solar vacuum thermal-arrest pipe of plate receiver if keep the efficiency equal with round cast receiver in the application of CPC, plate receiver must the large tracts of land, need in addition with the form of outer glass pipe evacuation, the glass pipe also can be done very big, consequently cost is too high, it is unable commercial, and round cast receiver has fine thermal-arrest effect in the application based on CPC, but its manufacturing process is complicated, the cost is higher, for this reason, the utility model provides a solar vacuum thermal-arrest pipe based on CPC.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a solar vacuum heat collecting tube based on CPC for can guarantee under the prerequisite that maximum absorption solar heat, effectively reduce solar vacuum heat collecting tube's manufacturing cost.

In view of this, the present application provides a solar vacuum heat collecting tube based on CPC, including: the heat absorber comprises a glass tube cover, a heat absorber and a metal tube;

the metal tube and the heat absorber are both arranged in the glass tube cover;

the number of the heat absorbing bodies is at least three;

at least three heat absorbing bodies are arranged on the outer surface of the metal pipe at intervals and connected with the metal pipe.

Optionally, the number of heat absorbing bodies is four;

the four heat absorbing bodies form a cross-shaped heat absorbing structure.

Optionally, the metal tube is a metal U-shaped tube.

Optionally, the metal tube is a metal straight tube or a countercurrent tube.

Optionally, the relative position angle between the cross-shaped heat absorption structure and the metal U-shaped pipe is 20-80 °.

Optionally, an included angle between the cross-shaped heat absorption structure and the metal U-shaped pipe is 45 °.

Optionally, the glass tube cover is disposed in an effective light-gathering area of the CPC light-gathering plate, and the relative position of the cross-shaped heat-absorbing structure and the CPC light-gathering plate is parallel to one side and perpendicular to the other side.

Optionally, the front and back faces of the heat absorber are provided with absorbing coatings.

Optionally, the metal tube is sealed with the glass tube cover.

Optionally, the metal tube is fused to the glass tube cover by a fusion seal.

According to the technical scheme, the embodiment of the application has the following advantages: comprises a glass tube cover, a heat absorber and a metal tube; the metal tube and the heat absorber are both arranged in the glass tube cover; the number of the heat absorbing bodies is at least three; at least three heat-absorbing bodies are arranged on the outer surface of the metal tube at intervals and are connected with the metal tube, the manufacturing cost is low, the process is simple, the heat collecting efficiency which is the same as that of a receiver vacuum heat collecting tube of a circular tube type can be achieved in application based on CPC, and therefore the production cost can be effectively reduced on the premise that the maximum absorption of solar heat is guaranteed.

Drawings

FIG. 1 is a schematic structural diagram of a CPC-based solar vacuum heat collecting tube in an embodiment of the present application when a metal U-shaped tube is used;

FIG. 2 is a top view of a CPC-based evacuated solar collector tube in an embodiment of the present application, which is a metal U-tube;

FIG. 3 is a schematic view of the structure of FIG. 1 with the melt seal and CPC collection panel removed;

FIG. 4 is a top view of a CPC-based evacuated solar collector tube in an embodiment of the present application, which is a metal straight tube;

FIG. 5 is a schematic structural diagram of a CPC-based solar vacuum heat collecting tube in the embodiment of the present application when a metal straight tube is adopted;

FIG. 6 is a schematic structural diagram of a Y-shaped heat absorbing structure in an embodiment of the present application;

FIG. 7 is a schematic structural view of a cross-type heat absorbing structure in an embodiment of the present application;

FIG. 8 is a schematic structural diagram of a counter-current tube in an embodiment of the present application;

FIG. 9 is a schematic view of the connection structure of the countercurrent tube and the cross-shaped heat absorbing structure in the embodiment of the present application;

FIG. 10 is a view of a CPC-based evacuated solar collector tube in an embodiment of the present application;

wherein the reference numerals are:

the solar heat collector comprises a glass tube cover 1, a metal U-shaped tube 2, a cross heat absorption structure 3, a fusion sealing part 4, a CPC light gathering plate 5, a metal straight-through tube 6, a heat absorption structure 7-Y, a heat absorption structure 8-cross and a counter-flow tube 9.

Detailed Description

In order to make the technical solutions of the present application better understood, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are intended to be inclusive and mean, for example, that they may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

The inventor finds that: according to the shape division of the receiver surface heat-absorbing body, the receivers on the market at present are mainly divided into flat plate type receivers and round tube type receivers, and the shape of the receiver surface heat-absorbing body can directly influence the heat collection efficiency and the production cost of the solar vacuum heat collection tube. In the application based on the CPC, if the plate type receiver wants to receive the solar rays reflected by the Compound Parabolic Concentrator (CPC) to the maximum extent, the area of a heat absorbing body needs to be very large, and the heat absorbing body is completely covered by a glass tube because the heat collector needs to be in a vacuum environment, so that the caliber of the glass tube of the whole solar vacuum heat collecting tube is very large, and the economy and the practicability are not met; the circular tube receiver has a good heat collection effect, can receive the solar rays reflected by the Compound Parabolic Concentrator (CPC) to the maximum extent, however, the process of making the heat absorber into the circular tube structure is complex, which results in higher cost, secondly, the receiver and the heat absorber are of a 'separated' structure, the problems of firmness and thermal expansion are considered in the fixing mode, and the process is complex and also results in higher cost. Therefore, the CPC-based solar vacuum heat collecting tube can greatly reduce the production cost of the solar vacuum heat collecting tube on the premise of ensuring that the solar energy is received to the maximum extent.

The present application provides an embodiment of a CPC-based solar vacuum thermal-collecting tube, and particularly refers to fig. 1.

The solar vacuum heat collecting tube based on CPC in this embodiment includes: the glass tube cover 1, the heat absorber and the metal tube; the metal tube and the heat absorber are both arranged in the glass tube cover 1; the number of the heat absorbing bodies is at least three; at least three heat absorbers are arranged on the outer surface of the metal tube at intervals and connected with the metal tube.

It should be noted that: the solar heat collector is provided with a glass tube cover 1, a heat absorber and a metal tube; the metal tube and the heat absorber are both arranged in the glass tube cover 1; the number of the heat absorbing bodies is at least three; at least three heat-absorbing bodies are arranged on the outer surface of the metal tube at intervals and are connected with the metal tube, the manufacturing cost is low, the process is simple, the heat collecting efficiency which is the same as that of a receiver vacuum heat collecting tube of a circular tube type can be achieved in application based on CPC, and therefore the production cost can be effectively reduced on the premise that the maximum absorption of solar heat is guaranteed.

The first embodiment of the CPC-based evacuated solar collector tube provided in the embodiments of the present application is described above, and the second embodiment of the CPC-based evacuated solar collector tube provided in the embodiments of the present application is described below, with reference to fig. 1 to 10.

It can be understood that: the number of heat absorbing bodies can be three, and the three heat absorbing bodies form a Y-shaped heat absorbing structure 7 shown in FIG. 6; the number of heat absorbing bodies may be four, the four heat absorbing bodies constituting a cross type heat absorbing structure 8 as shown in fig. 7; similarly, the number of the heat absorbing bodies can be more than four, so as to form a radial heat absorbing structure similar to a Chinese character mi. Preferably, the number of heat absorbers is four, the four heat absorbers constituting a cross-shaped heat absorption structure 3.

As shown in fig. 4 and 5, the metal pipe may be a metal through pipe 6, the metal through pipe 6 is located at the center of the glass tube cover 1, and both ends of the metal through pipe 6 are respectively welded with both ends of the glass tube cover 1 through the welding and sealing members 4, and it can be understood that: the metal through pipe 6 may also be sealed with the glass tube cover 1 by a hot press sealing technique or other methods, which are not limited herein.

As shown in fig. 8 and 9, the metal pipe may also be a counter flow pipe 9, i.e. water flows in from the middle and out from both ends to take away heat, so as to have good heat dissipation effect.

Preferably, as shown in fig. 1 and 2, the metal pipe is a metal U-shaped pipe 2, and the metal U-shaped pipe 2 is adopted without adopting an expansion joint, so that the process complexity is greatly reduced; one end of the metal U-shaped tube 2 is welded to one end of the glass tube cover 1 by a welding piece 4, and it can be understood that: the metal U-shaped tube 2 may also be sealed with the glass tube cover 1 by a hot press sealing technique or other methods, which are not limited herein.

It should be noted that: the sealing process of the melt seal is adopted, namely the metal pipe is welded with the glass pipe cover 1 through the melt seal part 4, wherein the melt seal part 4 is used as a transition material to melt seal glass and metal together, so that the heat collection temperature is increased to more than 100 ℃ without damaging the pipe, the application field can be increased to 80-250 ℃, the application range is wider, and the application of CPC is more met.

As shown in FIG. 3, the relative position angle between the cross-shaped heat absorption structure 3 and the metal U-shaped pipe 2 is 20-80 degrees, preferably, the relative position angle between the cross-shaped heat absorption structure 3 and the metal U-shaped pipe 2 is 45 degrees, and the condition that the metal is deformed by heating can be reasonably buffered.

Glass tube cover 1 sets up in the effective light-gathering area of CPC solar panel 5, and the relative position of cross heat-absorbing structure 3 and CPC solar panel 5 is the parallel one side on one side vertically relation, and this relative position has decided it can guarantee the absorption solar ray of at utmost to guarantee collecting efficiency.

The front surface and the back surface of the heat absorbing body are both provided with absorbing coatings, and the absorbing coatings are sprayed on the cross-shaped heat absorbing structure 3 in a double-surface spraying mode, so that the heat absorbing structure can well absorb heat generated by sunlight and transfer the heat to the metal pipe.

Vacuum is formed between the metal tube and the glass tube cover 1, and the following description is required: the space between the metal tube and the glass tube cover 1 needs to be vacuumized to ensure that the heat of the receiver cannot be directly radiated from the glass tube cover 1.

The cross heat absorption structure 3 is welded on the metal tube, so that the cross heat absorption structure 3 and the metal tube are integrated into a whole, and the manufacturing cost of the solar vacuum heat collection tube is greatly reduced through the process.

The cross-shaped heat absorption structure 3 is not in direct contact with the glass tube cover 1; the cross-shaped heat absorbing structure 3 is made of a copper substrate.

The solar vacuum heat collecting tube can obtain the same sunlight receiving efficiency as a round tube type receiver vacuum heat collecting tube through tests and computer simulation, and has the advantages of low manufacturing cost and simple process, thereby reducing the cost of the receiver.

The above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.

Claims

1. The utility model provides a solar vacuum heat collecting tube based on CPC which characterized in that includes: the heat absorber comprises a glass tube cover, a heat absorber and a metal tube;

the metal tube and the heat absorber are both arranged in the glass tube cover;

the number of the heat absorbing bodies is at least three;

2. The CPC-based solar vacuum thermal collector tube according to claim 1, wherein the number of the heat absorbing bodies is four;

the four heat absorbing bodies form a cross-shaped heat absorbing structure.

3. The CPC-based solar vacuum thermal collector tube according to claim 2, wherein the metal tube is a metal U-tube.

4. The CPC-based solar vacuum thermal collector tube according to claim 2, wherein the metal tube is a metal straight tube or a counterflow tube.

5. The CPC-based solar evacuated collector tube according to claim 3, wherein the relative position angle of the cross heat absorbing structure and the metal U-shaped tube is 20-80 degrees.

6. The CPC-based solar evacuated collector tube according to claim 5, wherein the relative position angle of the cross heat absorbing structure and the metal U-shaped tube is 45 degrees.

7. The CPC-based solar vacuum thermal collector tube according to claim 2, wherein the glass tube cover is disposed in an effective light-collecting area of the CPC light-collecting plate, and the cross-shaped heat absorbing structure is disposed opposite to the CPC light-collecting plate with one side parallel to the other side perpendicular to the other side.

8. The CPC-based solar vacuum thermal collector tube according to claim 1, wherein both front and back sides of the heat absorber are provided with an absorbing coating.

9. The CPC-based solar vacuum thermal collector tube of claim 1, wherein the metal tube is sealed to the glass tube shield.

10. The CPC-based solar vacuum thermal collector of claim 9, wherein the metal tube is fused to the glass tube cover by a fusion seal.