Solar thermal collector with layered heating control of water tank

Abstract

The invention provides a water tank layered heating control solar heat collector, which comprises a heat collection component and a water tank, the heat collection component is a pulsating heat pipe, the pulsating heat pipe comprises a plurality of parallel heat exchange pipes, the adjacent heat exchange pipes are communicated through upper and lower U-shaped pipes, the leftmost heat exchange pipe is communicated with the rightmost heat exchange pipe through a communicating pipe, and the communicating pipe is communicated with the water tank. A series loop structure is formed among the horizontal pipe, the U-shaped pipe and the communicating pipe; the communicating pipe is located on the upper portion of the upper U-shaped pipe, a gap is formed between the communicating pipe and the upper U-shaped pipe, the heat release part comprises the upper portion of the heat exchange pipe, the upper U-shaped pipe and the communicating pipe, an upper layer and a lower layer are arranged in the water tank through a layering partition plate, and the upper layer and the lower layer are provided with an inlet and an outlet respectively. According to the novel solar heat collector, water at different temperatures can be output, different requirements are met, and meanwhile the heat collection effect is improved.

Description

Technical Field

[0001] The present invention relates to a solar collector, and more particularly to a solar collector with stratified heating control for a water tank. Background Art

[0002] With the rapid development of modern social economy, the demand for energy by mankind is increasing. However, the reserves of traditional energy sources such as coal, oil, and natural gas are continuously decreasing and becoming increasingly scarce, resulting in continuous price increases. At the same time, the environmental pollution problems caused by conventional fossil fuels are becoming more and more serious, which greatly restricts the development of society and the improvement of the quality of human life. The energy problem has become one of the most prominent problems in the contemporary world. Therefore, seeking new energy sources, especially pollution-free clean energy, has become a research hotspot for people nowadays.

[0003] Solar energy is a clean energy source that is inexhaustible and has a huge amount of resources. The total amount of solar radiation energy received by the earth's surface every year is 1×10 18 kW·h, which is more than ten thousand times the total annual energy consumption of the world. However, due to the small energy density of solar radiation reaching the earth (about one kilowatt per square meter) and its discontinuity, it brings certain difficulties to large-scale development and utilization. Therefore, in order to widely utilize solar energy, not only technical problems need to be solved, but also it must be economically competitive with conventional energy sources.

[0004] The pulsating heat pipe is a new type of heat pipe technology that emerged in the early 1990s. The world's first pulsating heat pipe was invented by the Japanese Akaji in 1990. It is formed by bending a metal capillary into a serpentine structure without any capillary wick inside. As a new type of heat dissipation and cooling technology, the pulsating heat pipe has the advantages of simple structure, small size, light weight, easy manufacturing, low cost, and excellent performance. The operating principle and heat transfer characteristics of the pulsating heat pipe are very different from those of traditional heat pipes. When the pulsating heat pipe is working, it can generally be divided into three parts. The two ends of the pipe are the heating section and the cooling section respectively, and the middle part of the pipe is the adiabatic section, which can also be omitted. The operating principle of the pulsating heat pipe is as follows: when the pipe diameter is small enough, a series of vapor plugs and liquid plugs will be formed inside the pipe; in the heating section, the liquid film between the vapor bubble or vapor column and the pipe wall will be continuously heated and evaporated, resulting in the expansion of the vapor bubble and the increase of pressure; at the same time, in the cooling section, the vapor bubble will condense, shrink, and burst, resulting in a decrease in pressure, causing a driving pressure difference between the heating section and the condensation section, and promoting the reciprocating movement of the vapor and liquid slugs between the heating section and the cooling section, and the heat is transferred from one end to the other end, thus realizing heat transfer or temperature control. It can be seen that in the pulsating heat pipe, the phase change of the working fluid mainly provides power for the working fluid, and the proportion of phase change heat transfer in the total heat transfer flux of the pulsating heat pipe is relatively small. The heat pipe mainly relies on the sensible heat change of the working fluid to achieve heat transfer.

[0005] There are also technologies that combine pulsating heat pipes with solar energy in the prior art. However, the above combination uses solar energy as a heat source to achieve very simple evaporation and condensation. When the heat release part of the current pulsating heat pipe dissipates heat through condensation, since the heat release part has bent pipes and a connecting pipe that connects the two outermost pipes, when the fluid passes through the heat release part to absorb heat, the best heat absorption effect cannot be achieved, and at the same time, the multifunctional requirements for hot water cannot be met. Summary of the Invention

[0006] In order to overcome the defects and deficiencies existing in the prior art, the present invention provides a solar collector with a new structure, which can achieve sufficient heat release and heat exchange of the heat release part, improve the heat release effect, and also meet diversified requirements.

[0007] In order to achieve the above object, the technical solution of the present invention is as follows:

[0008] A solar collector with stratified heating control for a water tank, comprising a heat collection component and a water tank. The heat collection component includes a heat absorption part and a heat release part. The heat absorption part absorbs solar heat, and the heat release part is inserted into the water tank. The characteristic is that the heat collection component is a pulsating heat pipe, and the pulsating heat pipe includes multiple parallel heat exchange pipes. Adjacent heat exchange pipes are connected through upper and lower U-shaped pipes. Among them, the leftmost and rightmost heat exchange pipes are connected through a connecting pipe. A series loop structure is formed between the horizontal pipes, U-shaped pipes, and connecting pipes. The connecting pipe is located above the upper U-shaped pipe and there is a gap between the connecting pipe and the upper U-shaped pipe. The heat release part includes the upper part of the heat exchange pipe, the upper U-shaped pipe, and the connecting pipe. The water tank is internally provided with an upper layer and a lower layer through a stratified partition board, and the upper layer and the lower layer respectively have an inlet and an outlet.

[0009] As an improvement, the upper layer includes the connecting pipe, the upper part of the leftmost heat exchange pipe, and the upper part of the rightmost heat exchange pipe, and the lower layer includes the upper U-shaped pipe and the upper part of the heat exchange pipe.

[0010] As an improvement, the inlet and outlet of the upper layer are respectively arranged on the left and right sides of the water tank, and the inlet and outlet of the lower layer are respectively arranged on the left and right sides of the water tank, and the inlets of the upper layer and the lower layer are not on the same side.

[0011] As an improvement, the stratified partition board includes a horizontal section located in the gap, extending sections extending downward from both ends of the horizontal section, and connecting sections connecting the extending sections to the left and right walls of the water tank. A baffle is arranged in the lower layer. The baffle includes a first baffle and a second baffle arranged at intervals. The first baffle extends downward from the horizontal section, and the second baffle extends upward from the lower wall of the water tank. The heat exchange pipe is arranged between adjacent baffles, and the upper U-shaped pipe is arranged in the gap between the second baffle and the stratified partition board.

[0012] As an improvement, the flow direction of the water in the upper layer is opposite to that of the fluid in the connecting pipe, and the flow direction of the water in the lower layer is opposite to that of the fluid in the U-shaped pipe.

[0013] As an improvement, along the flow direction of the water in the lower layer, the lengths of the upward baffle plate extending downward and the downward baffle plate extending downward gradually decrease.

[0014] As an improvement, along the flow direction of the water in the lower layer, the amplitude of the gradual decrease in the lengths of the upward baffle plate extending downward and the downward baffle plate extending downward continuously increases.

[0015] As an improvement, the heat absorption part further includes a reflecting mirror, and the heat exchange tube is arranged at the focal position of the reflecting mirror.

[0016] As an improvement, the reflecting mirror includes a plurality of side-by-side arrangements, and each heat exchange tube is correspondingly provided with a reflecting mirror.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. By stratifying the water tank, the present invention can output hot water at different temperatures, which can meet different living needs.

[0019] 2. By stratifying the water tank, the heat release part of the pulsating heat pipe is located in different layers. After the pulsating heat pipe is heated, a circulating flow will be formed. However, due to different heating directions, the flow direction may be uncertain. The present invention includes an upper layer and a lower layer in the water tank, and the two layers are separated by a partition. The inlets of the upper layer and the lower layer are not on the same side, which can enable heat exchange in the upper and lower layers respectively. In this way, no matter which direction the heat pipe flows, sufficient heat exchange can be carried out. If the flow directions of the upper and lower layers are opposite to the flow direction of the fluid in the heat pipe, it is exactly the best countercurrent flow heat exchange effect of the heat exchanger. If the flow directions of the upper and lower layers are the same as the flow direction of the fluid in the heat pipe, heat exchange can be carried out between the two fluids through heat conduction between the partitions, compensating for the problem that the temperature difference change caused by the co-current flow is too large and the heat exchange effect is insufficient, and making the heat exchange more sufficient. Brief Description of the Drawings

[0020] Figure 1 is a schematic structural diagram of the solar collector of the present invention;

[0021] Figure 2 is a schematic structural diagram of the heat collection component and the water tank integration of the water tank of the present invention;

[0022] Figure 3 is a schematic structural diagram of the heat collection component of the present invention. Detailed Embodiment

[0023] The following will make a detailed description of the specific embodiment of the present invention in conjunction with the drawings.

[0024] Figures 1-3 shows the solar collector of the present invention. As Figure 1 shown, the solar collector includes a water tank 1 and a heat collection component. The heat collection component 2 includes a heat absorption part 21 and a heat release part 22. The heat absorption part 21 absorbs solar heat, and the heat release part is inserted into the water tank 1, and the heat is transferred to the water in the water tank 1 through the heat release part 22.

[0025] As an improvement, the heat collection component is a pulsating heat pipe. The pulsating heat pipe includes a plurality of parallel heat exchange pipes 23. Adjacent heat exchange pipes are connected through upper and lower U-shaped pipes 24 and 25. Among them, the leftmost and rightmost heat exchange pipes 23 are connected through a connecting pipe 26. A series loop structure is formed among the heat exchange pipes 23, U-shaped pipes 24, 25 and the connecting pipe 26; the connecting pipe 26 is located above the upper U-shaped pipe 24 and a gap 27 is provided between the connecting pipe 26 and the upper U-shaped pipe 24. The heat release part 22 includes the upper part of the heat exchange pipe 23, the upper U-shaped pipe 24 and the connecting pipe 26. In the water tank 1, an upper layer 12 and a lower layer 13 are arranged through a layered partition 11. The upper layer and the lower layer respectively have inlets 14, 15 and outlets 16, 17.

[0026] By stratifying the water tank, the present invention can output hot water at different temperatures, which can meet different living needs. For example, the heat exchange areas of the upper layer and the lower layer can be set according to needs, so as to achieve different temperature requirements and realize diversified demands.

[0027] As an improvement, the upper layer 12 includes the connecting pipe, the upper parts of the leftmost heat exchange pipe and the rightmost heat exchange pipe, and the lower layer includes the upper U-shaped pipe and the upper part of the heat exchange pipe. The heat exchange area of the upper layer is smaller than that of the lower layer. Therefore, the water temperature output by the upper layer is generally lower than that output by the lower layer, and different demands can be realized for different water temperatures.

[0028] The inlets and outlets of the upper layer and the lower layer of the present invention are respectively located on both sides of the water tank. Because when the heat absorption part of the heat pipe absorbs heat, the circulation direction of the fluid in the heat pipe may change with the size of the heat received at different positions. At this time, setting the inlets and outlets of the upper and lower layers on both sides can determine the positions of the inlets and outlets according to the actual fluid flow direction in the heat pipe, that is, the positions of the inlets and outlets can be changed according to needs, so as to achieve different heat exchange demands. For example, in order to pursue the maximum heat exchange, the fluid in the heat exchange pipe section is counter-flow heat exchanged. Or in order to avoid too high output temperature, the fluid in the upper layer can adopt a co-flow heat exchange in the same direction as the fluid flow direction in the heat pipe, and the lower layer can adopt a counter-flow heat exchange in the direction inconsistent with the fluid flow direction in the heat pipe, so as to transfer the heat that the upper fluid exchanges less to the lower layer.

[0029] As an improvement, the upper inlet 14 and the upper outlet 16 are respectively arranged on the left side and the right side of the water tank, and the lower inlet 15 and the lower outlet 17 are respectively arranged on the left side and the right side of the water tank, wherein the upper inlet and the lower inlet are not on the same side. As Figure 2 shown, the upper and lower inlets are respectively on the left side and the right side. The layered partition is a heat conductor, and the fluids in the upper layer and the lower layer can exchange heat through the partition. By arranging the layered heat-conducting partition, heat exchange between the fluids in the upper and lower layers can be realized, so that the heat of the upper and lower layers is complementary, and the fluid with a higher temperature in the upper and lower layers transfers heat to the fluid with a lower temperature, and then the fluid with a higher temperature cools down and absorbs the heat of the heat pipe, thereby realizing the maximum heat exchange amount. Through the heat conduction and heat complementarity of the partition, the best heat exchange effect can be achieved as much as possible whether it is countercurrent or concurrent heat exchange.

[0030] As an improvement, the layered partition includes a horizontal section 111 located in the interval, extending sections 112 extending downward from both ends of the horizontal section, and connecting sections 113 connecting the extending sections to the left and right walls of the water tank. A baffle is arranged in the lower layer. The baffle includes a first baffle 7 and a second baffle 8 arranged at intervals. The first baffle extends downward from the horizontal section, and the second baffle extends upward from the lower wall of the water tank. The heat exchange tubes are arranged between adjacent baffles, and the upper U-shaped tubes are arranged in the gap between the second baffle and the layered partition.

[0031] By arranging the upper and lower layers in the present invention and arranging a baffle structure in the lower layer, the heat exchange tube sections at different positions of the heat release part of the pulsating heat pipe can be adapted to the layer shape, so that the heat exchange fluid can fully contact the heat exchange tube sections, improving the heat exchange effect.

[0032] As an improvement, the flow direction of the water in the upper layer is opposite to the flow direction of the fluid in the communicating pipe, and the flow direction of the water in the lower layer is opposite to the flow direction of the fluid in the U-shaped pipe. The above can make the flow paths of the fluid and the fluid in the heat pipe in the layer opposite, so as to realize the maximum heat exchange amount. By realizing layered flow, true countercurrent flow can be completely realized.

[0033] As an improvement, along the flow direction of the water in the lower layer, the lengths of the upper baffle extending downward and the lower baffle extending downward first gradually increase, reach the middle position of the lower flow channel and then gradually decrease. Because the positions of the connection sections are the outlets and inlets of the upper and lower layers respectively, or the inlets and outlets of the upper and lower layers respectively, at this time the temperature difference between the two is the largest and the heat exchange effect is the best. Because of the change in the extension length of the baffle, the heat exchange area and the flow disturbance effect in the middle position are increased, thereby increasing the heat transfer coefficient and the heat exchange effect, making the overall heat exchange amount balanced, realizing overall heat exchange balance, and further achieving the best heat exchange effect.

[0034] As an improvement, the left end of the left connecting part is located at a position below the middle of the left side wall of the water tank, and the right end of the right connecting part is located at a position below the middle of the right side wall. Since the area of the lower inner heat exchange tubes is larger than that of the upper inner heat exchange tubes, with the above structure, the heat exchange area of the fluid in the upper layer is increased as much as possible, and the fluid path is as long as possible, so that the upper and lower heat exchanges are relatively balanced.

[0035] As an improvement, along the flow direction of the water in the lower layer, the lengths of the upward baffle plate extending downward and the downward baffle plate extending downward first gradually increase with an increasing amplitude, reach the middle position of the lower flow channel and then gradually decrease with an increasing amplitude. The above setting can further achieve overall heat exchange balance and improve the heat exchange effect.

[0036] As an improvement, the partition plate is a structure symmetric about the middle position of the lower wall surface of the water tank.

[0037] As an improvement, the heat conduction performance of different positions of the partition plate is different. Among them, the heat conduction performance of the horizontal section is greater than that of the extending section, and the heat conduction performance of the extending section is greater than that of the connecting section. Because when the inlets of the upper layer and the lower layer are not on the same side of the water tank, the positions of the first parallel part and the third parallel part are the outlets and inlets of the upper layer and the lower layer respectively, or the inlets and outlets of the upper layer and the lower layer respectively. At this time, the temperature difference between the two is the largest and the heat exchange effect is the best. By increasing the heat conduction coefficient of the middle position, the heat exchange effect is increased, so that the overall heat exchange amount reaches balance and the overall heat exchange balance is realized, thus further achieving the best heat exchange effect.

[0038] As an improvement, the heat absorption capacity of the water in the upper layer is less than that of the water in the lower layer. Because the heat exchange area in the upper part is small, by the different heat absorption capacities of the fluid, the different heat exchange amounts caused by different heat exchange areas are satisfied, so as to realize the heat exchange balance between the upper and lower heat pipes as a whole.

[0039] As an improvement, the heat absorption part further includes a reflecting mirror 6, and the heat exchange tube is arranged at the focal position of the reflecting mirror.

[0040] As an improvement, as Figure 3 shown, the reflecting mirror 6 includes a plurality of arranged side by side, and each heat exchange tube 6 is correspondingly provided with a reflecting mirror.

[0041] The solar collector further includes a transparent cover plate 3, a heat insulation layer 4, and a heat absorption film. The heat absorption film is arranged on the upper surface (i.e., the side facing the sun) of the heat exchange tubes of the heat collection component, the transparent cover plate 3 is arranged on the upper surface of the heat exchange tubes of the heat collection tube, and a heat insulation layer 4 is arranged between the heat exchange tube and the transparent cover plate.

[0042] Although the present invention has been disclosed above in preferred embodiments, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. A solar collector with water tank stratified heating control, comprising a heat collecting component and a water tank, wherein the heat collecting component comprises a heat absorbing part and a heat releasing part, wherein the heat absorbing part absorbs solar heat, and the heat releasing part is inserted into the water tank, characterized in that: The heat collecting component is a pulsating heat pipe, which includes a plurality of parallel heat exchange tubes, wherein adjacent heat exchange tubes are connected via upper and lower U-shaped tubes, wherein the leftmost and rightmost heat exchange tubes are connected via a connecting tube, and a series loop structure is formed between the heat exchange tubes, the U-shaped tubes and the connecting tubes; the connecting tube is located at the upper part of the upper U-shaped tube and a gap is arranged between the connecting tube and the upper U-shaped tube, the heat releasing part includes the upper part of the heat exchange tube, the upper U-shaped tube and the connecting tube, and the upper and lower layers are arranged in the water tank via a layered partition, wherein the upper and lower layers have an inlet and an outlet respectively.

2. The solar thermal collector according to claim 1, characterized in that: The upper layer includes the connecting tube, the upper part of the leftmost heat exchange tube and the upper part of the rightmost heat exchange tube, and the lower layer includes the upper U-shaped tube and the upper part of the heat exchange tube.

3. The solar thermal collector according to claim 2, characterized in that: The inlet and outlet of the upper layer are respectively arranged on the left and right sides of the water tank, and the inlet and outlet of the lower layer are respectively arranged on the left and right sides of the water tank, wherein the inlet of the upper layer and the inlet of the lower layer are not on the same side.

4. The solar thermal collector according to claim 3, characterized in that: The layered partition includes a horizontal section located in the interval, an extension section extending downward from both ends of the horizontal section, and a connecting section connecting the extension section with the left wall and the right wall of the water tank, wherein baffles are arranged in the lower layers, and the baffles include a first baffle and a second baffle arranged at intervals, the first baffle extends downward from the horizontal section, and the second baffle extends upward from the lower wall of the water tank, the heat exchange tube is arranged between adjacent baffles, and the upper U-shaped tube is arranged in the gap between the second baffle and the layered partition.

5. The solar thermal collector according to claim 4, characterized in that: The flow direction of the water in the upper layer is opposite to the flow direction of the fluid in the connecting tube, and the flow direction of the water in the lower layer is opposite to the flow direction of the fluid in the U-shaped tube.

6. The solar thermal collector according to claim 5, characterized in that: Along the flow direction of water in the lower layer, the length of the upper baffle extending downward and the length of the lower baffle extending upward gradually decrease.

7. The solar thermal collector according to claim 6, characterized in that: Along the flow direction of water in the lower layer, the length of the upper baffle extending downward and the length of the lower baffle extending upward gradually decrease at an increasing rate.

8. The solar thermal collector according to claim 1, characterized in that: The heat absorption part also includes a reflector, and the heat exchange tube is arranged at the focal position of the reflector.

9. The solar thermal collector according to claim 8, characterized in that: The reflectors include a plurality of reflectors arranged side by side, and each heat exchange tube is correspondingly provided with a reflector.

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