All-glass composite parabolic internal concentrating eccentric vacuum tube type solar medium temperature collector

Abstract

The present invention discloses a solar medium temperature collector with an all-glass composite parabola and an eccentric vacuum tube. It includes a heat collecting tube, a heat receiving tube, an insulation header and a water collecting tube group; the heat collecting tube is arranged on the insulation header; the heat receiving tube is arranged in the heat collecting tube; the water collecting tube group is arranged in the insulation header; the heat receiving tube is connected with the water collecting tube group; the heat collecting tube is provided with a heat receiving tube; the heat collecting tube is approximately elliptical; the heat collecting tube includes a first heat collecting tube structure, a second heat collecting tube structure and a third heat collecting tube structure; the first heat collecting tube structure is a U-shaped structure with an opening downward; the two ends of the first heat collecting tube structure are respectively connected to one end of the second heat collecting tube structure and the third heat collecting tube structure; the second heat collecting tube structure is connected to the other end of the third heat collecting tube structure; the heat receiving tube is located below the center point of the cross section of the heat collecting tube and above the connection point of the second heat collecting tube structure and the third heat collecting tube structure. The present invention has the advantages of small size, light weight and large heat collecting area.

Description

Technical Field

[0001] The invention relates to the technical field of solar energy collection and application, and more specifically to a full-glass composite parabola internal focusing eccentric vacuum tube type solar medium-temperature collector. Background Art

[0002] In recent years, solar water heaters based on ordinary all-glass vacuum tubes are successful products for low-temperature applications of solar thermal conversion (below 100°C). They have been widely popularized in society and have played a positive role in energy saving, environmental protection and carbon reduction. The medium-temperature application of solar thermal conversion (100-250°C) has a wide market demand and positive effects of energy saving, environmental protection and carbon reduction. For example, the chemical, food, textile, catering, clothing, medicine and other industries have urgent needs. At present, this urgent demand has not been met and can only be solved by traditional coal combustion, gas combustion or electricity consumption. The existing ordinary all-glass vacuum tube solar water heaters (including heat pipe solar water heaters) cannot work at a higher working temperature due to their heat collection principle and structural design. In the temperature range of solar medium-temperature application (100-250°C), the heat collection efficiency is very low, thus losing practical value. Faced with the urgent demand for medium-temperature applications of solar energy (100-250℃) and the world trend of energy conservation, environmental protection, and carbon reduction, only by developing a new type of internally concentrating vacuum tube solar collector with relatively high concentration and relatively high thermal efficiency can this demand be met and it is in line with the world trend of energy conservation, environmental protection, and carbon reduction.

[0003] The existing publication number is: CN107228491A, a CPC composite parabola internal concentrating vacuum tube solar collector with an asymmetric receiving angle of a heat-receiving glass tube, which discloses a reflector and a reflective film arranged in the heat collecting tube, which requires the installation of the reflector in the heat collecting tube, and has complex operation, large volume, heavy weight, small heat collecting area, and cannot perform medium-temperature heat collection well.

[0004] Therefore, it is necessary to develop a medium-temperature solar collector that is easy to operate, small in size, light in weight, and has a large solar collection area. Summary of the invention

[0005] The purpose of the present invention is to provide a full-glass composite parabola internal focusing eccentric vacuum tube type solar medium temperature collector, which is easy to operate, small in size, light in weight and has a large heat collection area.

[0006] In order to achieve the above-mentioned object, the technical scheme of the present invention is: a full-glass composite parabola internal focusing eccentric vacuum tube type solar medium temperature collector, characterized in that it includes a heat collecting tube, a heat receiving tube, a heat insulation header and a water collecting tube group;

[0007] The heat collecting tube is arranged on the heat-insulating header;

[0008] The heat receiving tube is arranged in the heat collecting tube;

[0009] The water collecting pipe group is arranged in the heat-insulating header box;

[0010] The heat receiving pipe is connected with the water collecting pipe group;

[0011] The casing of the water collecting tube group extends partially into the heated tube, and the fins are located inside the water collecting tube group;

[0012] The heat collecting tube includes a first heat collecting tube structure, a second heat collecting tube structure and a third heat collecting tube structure; the first heat collecting tube structure is a U-shaped structure with an opening downward; the first heat collecting tube structure is located above the second heat collecting tube structure and the third heat collecting tube structure;

[0013] The two ends of the first heat collecting tube structure are respectively connected to one end of the second heat collecting tube structure and the third heat collecting tube structure; the other end of the second heat collecting tube structure is connected to the other end of the third heat collecting tube structure; the heat receiving tube is located below the center point of the cross section of the heat collecting tube and above the connection point between the second heat collecting tube structure and the third heat collecting tube structure.

[0014] In the above technical solution, the second heat collecting tube structure and the third heat collecting tube structure are connected to form an inner focusing CPC double-sided involute structure with the opening facing upward.

[0015] In the above technical solution, the second heat collecting tube structure and the third heat collecting tube structure are symmetrical structures, and the inner surfaces of both are coated with a layer of metal film to form an inner light focusing reflective coating.

[0016] In the above technical solution, the water collecting pipe group includes a casing, a steam pipe and a water inlet pipe; the steam pipe is located above the water inlet pipe;

[0017] The sleeve comprises a first sleeve and a second sleeve; both ends of the first sleeve are open structures; one end of the first sleeve is connected to the steam pipe, and the other end extends into the second sleeve;

[0018] The second sleeve of the water collecting pipe group extends into the heated pipe;

[0019] One end of the second sleeve is an open structure and the other end is a closed structure; the open end of the second sleeve is connected to the water inlet pipe, and the closed end is located below the first sleeve;

[0020] The fin is located on the outer periphery of the first sleeve and on the inner side of the second sleeve; the first sleeve and the second sleeve are connected through the fin.

[0021] In the above technical solution, the fin is a hollow double-layer arc plate structure with an open upper end.

[0022] In the above technical solution, the heat receiving tube is located directly below the center point of the heat collecting tube and directly above the connection point between the second heat collecting tube structure and the third heat collecting tube structure.

[0023] In the above technical solution, a plurality of fixing brackets are located inside the heat collecting tube; the heat receiving tube is fixed inside the heat collecting tube by fixing brackets arranged at intervals.

[0024] In the above technical solution, the ratio of the height of the internal light-reflecting coating to the maximum outer diameter of the heated tube is greater than or equal to 2:5.

[0025] In the above technical solution, the getter is arranged in the heat collecting tube;

[0026] The insulation layer is arranged in the insulation header; the water collecting pipe group is arranged in the insulation layer;

[0027] A sealing ring is provided at the connection between the heat collecting tube and the insulation header;

[0028] The sealing ring is of a groove structure; the opening end of the sealing ring is clamped on the thermal insulation header, and the closed end is closely attached to the outer wall of the heat collecting tube.

[0029] In the above technical solution, the heat collecting tube, the heat receiving tube, the reflective plate and the fixing bracket are all made of glass.

[0030] The present invention has the following advantages:

[0031] (1) The involute reflector in the heat collecting tube can reflect and concentrate sunlight on the surface of the heat receiving tube with a high concentration ratio through the internal focusing light, and be absorbed by the selective reflective coating with high efficiency and converted into heat energy. Under the specific insulation conditions of the vacuum tube, the solar energy is converted into the heat energy of the water in the heated glass tube, making it superheated water with a temperature of 100-180℃. When the superheated water is released, it is converted into 100-200℃ steam, which can provide users with 100℃ boiling water (under one standard atmospheric pressure) or 100-200℃ steam.

[0032] (2) The present invention increases the heat collection area. The present invention converts the heating of the inner tube into the outer tube, and the steam output is large. The solar projection area is the heat collection area, which is suitable for industrial large-diameter solar energy applications. Optical fibers at any angle between sunrise and sunset can be reflected to the heat receiving tube with reflective coating through the CPC curve.

[0033] (3) The volume and weight of the present invention are reduced (due to the oval shape of the heat collecting tube, the weight is reduced by about 20%); the oval shape of the heat collecting tube in the present invention reduces the distance between the heat collecting tube and the heat receiving tube, reduces the volume, and saves costs;

[0034] (4) The present invention directly coats the inner wall of the heat collecting tube, eliminating the need for reflectors and other mechanisms; since the heat collecting tube refers to a vacuum structure, steam can be directly output;

[0035] (5) The heat collection temperature of the present invention is 80~130℃, which is medium-temperature solar thermal. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the internal structure of the present invention.

[0037] Figure 2 It is a schematic diagram of the cross-sectional structure of the heat collecting tube in the present invention.

[0038] Figure 3 It is a structural schematic diagram of the water collecting pipe group in the present invention.

[0039] Figure 4 It is a schematic diagram of the structure of the fin in the present invention.

[0040] Figure 5 It is a schematic diagram of the cross-sectional structure of the sealing ring in the present invention.

[0041] In the figure, 1-collecting tube, 1.1-first collecting tube structure, 1.2-second collecting tube structure, 1.3-third collecting tube structure, 2-heat receiving tube, 3-sealing ring, 4-insulating header, 5-water collecting tube group, 6-fixing bracket, 7-internal focusing reflective coating, 8-insulating layer, 9-degassing agent, 10-fin. DETAILED DESCRIPTION

[0042] The following is a detailed description of the implementation of the present invention in conjunction with the accompanying drawings, but they do not constitute a limitation of the present invention and are only given as examples. At the same time, the advantages of the present invention are made clearer and easier to understand through the description.

[0043] Referring to the attached drawings, it can be seen that the all-glass composite parabola internal concentrating eccentric vacuum tube type solar medium temperature collector is characterized by comprising a heat collecting tube 1, a heat receiving tube 2, a heat insulation header 4 and a water collecting tube group 5; the heat collecting tube 1 is a glass tube formed along the CPC curve;

[0044] The heat collecting tube 1 is arranged on the heat-insulating header 4;

[0045] The heat receiving tube 2 is arranged in the heat collecting tube 1;

[0046] The water collecting pipe group 5 is arranged in the heat-insulating header box 4;

[0047] The heat receiving tube 2 is connected to the water collecting pipe group 5;

[0048] The casing of the water collecting tube group 5 extends into the heat receiving tube 2, and the fin 10 is located between the casing of the water collecting tube group 5 and the heat receiving tube 2; the casing of the water collecting tube group 5 is connected to the heat receiving tube 2 through the fin;

[0049] The heat collecting tube 1 is approximately elliptical; the heat collecting tube 1 comprises a first heat collecting tube structure 1.1, a second heat collecting tube structure 1.2 and a third heat collecting tube structure 1.3; the first heat collecting tube structure 1.1 is a U-shaped structure with an opening facing downward; the first heat collecting tube structure 1.1 is located above the second heat collecting tube structure 1.2 and the third heat collecting tube structure 1.3;

[0050] The two ends of the first heat collecting tube structure 1.1 are seamlessly connected to one end of the second heat collecting tube structure 1.2 and the third heat collecting tube structure 1.3 respectively; the other ends of the second heat collecting tube structure 1.2 and the third heat collecting tube structure 1.3 are seamlessly connected; the heat receiving tube 2 is located below the center point of the cross section of the heat collecting tube 1 and above the connection point between the second heat collecting tube structure 1.2 and the third heat collecting tube structure 1.3.

[0051] Furthermore, the second heat collecting tube structure 1.2 and the third heat collecting tube structure 1.3 are connected to form an inner focusing CPC double-sided involute structure with the opening facing upward.

[0052] Furthermore, the second heat collecting tube structure 1.2 and the third heat collecting tube structure 1.3 are symmetrical structures, and the inner surfaces of both are coated with a layer of metal film to form an inner light focusing reflective coating 7.

[0053] In the above technical solution, the water collecting pipe group 5 includes a casing 5.1, a steam pipe 5.2 and a water inlet pipe 5.3; the steam pipe 5.2 is located above the water inlet pipe 5.3;

[0054] The sleeve 5.1 includes a first sleeve 5.11 and a second sleeve 5.12; both ends of the first sleeve 5.11 are open structures; one end of the first sleeve 5.11 is connected to the steam pipe 5.2, and the other end extends into the second sleeve 5.12;

[0055] The second sleeve 5.12 of the water collecting pipe group 5 extends into the heated pipe 2;

[0056] One end of the second sleeve 5.12 is an open structure and the other end is a closed structure; the open end of the second sleeve 5.12 is connected to the water inlet pipe 5.3, and the closed end is located below the first sleeve 5.11;

[0057] The fin 10 is located on the outer periphery of the first sleeve 5.11 and on the inner side of the second sleeve 5.12; the first sleeve 5.11 and the second sleeve 5.12 are connected through the fin 10.

[0058] In the above technical solution, the fin 10 is a hollow double-layer arc plate structure with an open upper end. The fin 10 adopts an elastic self-locking fin, which has the functions of heat conduction, self-locking and automatic positioning;

[0059] The fins include a first arc-shaped fin and a second arc-shaped fin; the first arc-shaped fin and the second arc-shaped fin are arranged at intervals, the first arc-shaped fin is located above the second arc-shaped fin, and both side ends of the first arc-shaped fin are respectively connected to both side ends of the second arc-shaped fin; an opening is arranged at the top of the second arc-shaped fin.

[0060] The inner arc of the fin is the same as the outer arc of the water collecting pipe group, and is automatically positioned; the radial fins are evenly distributed along the outer circle of the second sleeve 5.12 of the water collecting pipe group, which plays an automatic locking function; the upper part of the fin is open and positioned axially; because the two cantilever arcs at the opening of the fin 10 are elastically deformed downward by radial force, they can be easily inserted into the inner wall of the vacuum tube by pinching them by hand. After insertion, the cantilever arc of the fin automatically bounces upward and automatically fits tightly against the inner wall of the vacuum tube, which plays an elastic self-locking function.

[0061] Furthermore, the heat receiving tube 2 is located directly below the center point of the heat collecting tube 1 and directly above the connection point between the second heat collecting tube structure 1.2 and the third heat collecting tube structure 1.3.

[0062] Furthermore, a plurality of fixing brackets 6 are located in the heat collecting tube 1 ; the heat receiving tube 2 is fixed in the heat collecting tube 1 by the fixing brackets 6 arranged at intervals.

[0063] Furthermore, the ratio of the height of the inner light reflecting coating 7 to the maximum outer diameter of the heated tube 2 is greater than or equal to 2:5.

[0064] Furthermore, the getter 9 is arranged in the heat collecting tube 1;

[0065] The heat-insulating layer 8 is arranged in the heat-insulating header 4; the water collecting pipe group 5 is arranged in the heat-insulating layer 8;

[0066] A sealing ring 3 is provided at the connection between the heat collecting tube 1 and the heat preservation header 4 ; the open end of the sealing ring 3 is clamped on the heat preservation header 4 , and the closed end is closely attached to the outer wall of the heat collecting tube 1 .

[0067] Furthermore, the heat collecting tube 1, the heat receiving tube 2, the reflective plate and the fixing bracket 6 are all made of glass.

[0068] The working principle of the all-glass composite parabola internal concentrating eccentric vacuum tube type solar medium temperature collector described in the present invention is as follows: the lower part of the heat collecting tube 1 is a double-sided CPC involute internal concentrating structure, which can reflect all the light to the backlight surface of the heat receiving tube 2 to the maximum extent at any angle of the effective sunlight irradiation angle (the light-facing surface of the heat receiving tube 2 directly absorbs the direct sunlight), thereby absorbing the sunlight receiving area with the maximum efficiency under the condition of the minimum tube spacing, that is, the minimum area of ​​the heat collecting frame. At the same time, the water collecting pipe group is set up, which can fully heat the circulating water evenly and fully, and bring the heat out of the collector through the flow channel. Since the water volume in the water pipe group is small and the heating area of ​​the heated pipe is large enough, the collector can efficiently heat the circulating water to about 200℃ superheated water, and after releasing the closed pipeline, it is saturated steam.

[0069] Other parts not described belong to the prior art.

Claims

1. All-glass composite parabolic internal concentrating eccentric vacuum tube type solar medium temperature collector, characterized by: It comprises a heat collecting tube (1), a heat receiving tube (2), a heat-insulating header (4) and a water collecting tube group (5); The heat collecting tube (1) is arranged on the heat-insulating header (4); The heat receiving tube (2) is arranged inside the heat collecting tube (1); The water collecting pipe group (5) is arranged in the heat-insulating header box (4); The heat receiving pipe (2) is connected to the water collecting pipe group (5); The sleeve portion of the water collecting tube group (5) extends into the heat receiving tube (2), and the fin (10) is located inside the water collecting tube group (5); The heat collecting tube (1) comprises a first heat collecting tube structure (1.1), a second heat collecting tube structure (1.2) and a third heat collecting tube structure (1.3); the first heat collecting tube structure (1.1) is a U-shaped structure with an opening facing downward; the first heat collecting tube structure (1.1) is located above the second heat collecting tube structure (1.2) and the third heat collecting tube structure (1.3); The two ends of the first heat collecting tube structure (1.1) are respectively connected to one end of the second heat collecting tube structure (1.2) and the third heat collecting tube structure (1.3); the second heat collecting tube structure (1.2) is connected to the other end of the third heat collecting tube structure (1.3); the heat receiving tube (2) is located below the center point of the cross section of the heat collecting tube (1) and above the connection point between the second heat collecting tube structure (1.2) and the third heat collecting tube structure (1.3); The water collecting pipe group (5) comprises a casing (5.1), a steam pipe (5.2) and a water inlet pipe (5.3); the steam pipe (5.2) is located above the water inlet pipe (5.3); The sleeve (5.1) comprises a first sleeve (5.11) and a second sleeve (5.12); both ends of the first sleeve (5.11) are open structures; one end of the first sleeve (5.11) is connected to the steam pipe (5.2), and the other end extends into the second sleeve (5.12); The second sleeve (5.12) of the water collecting pipe group (5) extends into the heated pipe (2); One end of the second sleeve (5.12) is an open structure, and the other end is a closed structure; the open end of the second sleeve (5.12) is connected to the water inlet pipe (5.3), and the closed end is located below the first sleeve (5.11); The fin (10) is located on the outer periphery of the first sleeve (5.11) and on the inner side of the second sleeve (5.12); the first sleeve (5.11) and the second sleeve (5.12) are connected via the fin (10); A getter (9) is arranged in the heat collecting tube (1); The heat-insulating layer (8) is arranged in the heat-insulating header (4); the water collecting pipe group (5) is arranged in the heat-insulating layer (8); A sealing ring (3) is provided at the connection between the heat collecting tube (1) and the heat-insulating header (4); The sealing ring (3) is in a groove-shaped structure; the open end of the sealing ring (3) is clamped on the thermal insulation header (4), and the closed end is in close contact with the outer wall of the heat collecting tube (1).

2. The all-glass composite parabola internal focusing eccentric vacuum tube type solar medium temperature collector according to claim 1 is characterized by: The second heat collecting tube structure (1.2) and the third heat collecting tube structure (1.3) are connected to form an inner focusing CPC double-sided involute structure with the opening facing upward.

3. The all-glass composite parabola inner focusing eccentric vacuum tube type solar medium temperature collector according to claim 1 or 2, characterized in that: The second heat collecting tube structure (1.2) and the third heat collecting tube structure (1.3) are symmetrical structures, and the inner surfaces of both are coated with a layer of metal film to form an inner light focusing reflective coating (7).

4. The all-glass composite parabola internal focusing eccentric vacuum tube type solar medium temperature collector according to claim 1 is characterized by: The fin (10) is in the form of a hollow double-layer arc plate with an open upper end.

5. The all-glass composite parabola internal focusing eccentric vacuum tube type solar medium temperature collector according to claim 4 is characterized by: The heat receiving tube (2) is located directly below the center point of the heat collecting tube (1) and directly above the connection point between the second heat collecting tube structure (1.2) and the third heat collecting tube structure (1.3).

6. The all-glass composite parabola internal focusing eccentric vacuum tube type solar medium temperature collector according to claim 5 is characterized by: A plurality of fixing brackets (6) are located in the heat collecting tube (1); the heat receiving tube (2) is fixed in the heat collecting tube (1) via the fixing brackets (6) arranged at intervals.

7. The all-glass composite parabola inner focusing eccentric vacuum tube type solar medium temperature collector according to claim 6 is characterized by: The ratio of the height of the internal light-reflecting coating (7) to the maximum outer diameter of the heated tube (2) is greater than or equal to 2:

5.

8. The all-glass composite parabola internal focusing eccentric vacuum tube type solar medium temperature collector according to claim 1 is characterized by: The heat collecting tube (1), the heat receiving tube (2), the reflective plate and the fixing bracket (6) are all made of glass.

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