Unpowered phase change vaporization flat plate solar water heater

Abstract

The invention provides an unpowered phase change vaporization flat plate solar water heater, and belongs to the technical field of flat plate collectors. The unpowered phase change vaporization flat plate solar water heater comprises a heat preservation water tank and a heat collection flat plate, heat conduction water is injected into an inner cavity of the heat preservation water tank, a heat exchange pipe transversely penetrates through the heat preservation water tank, a closed red copper straight pipe and a closed header flow channel are fixed in the heat collection flat plate, and phase change heat conduction media easy to vaporize are injected into the red copper straight pipe and the header flow channel. A heat dissipation head inserted into the header runner is arranged at the end of the red copper straight pipe, a condensation head protruding upwards and penetrating out of the heat collection flat plate is arranged in the middle of the header runner, a heat absorption head connected with the inner cavity is arranged on the heat preservation water tank, and a heat exchange assembly for heat exchange is connected between the condensation head and the heat absorption head. The red copper straight pipes and the collecting pipe flow channels in the heat collecting flat plates are of a closed structure, phase change heat-conducting media in the heat collecting flat plates do not make contact with the outside, scaling is avoided, the heat collecting flat plates are resistant to low temperature, and heat-conducting water in the heat preservation water tank is not afraid of the influence of the low-temperature environment.

Description

Technical Field

[0001] The present invention belongs to the technical field of flat plate collectors, and relates to a non-powered phase change vaporization flat solar water heater. Background Art

[0002] Flat plate collectors mainly include an absorber plate, a diversion pipe, and a superconducting vacuum tube. The superconducting vacuum tube is mainly made of a glass tube or a copper tube. The superconducting vacuum tube is fixed on the absorber plate. A superconducting medium is filled in the vacuum glass tube or copper tube. The lower end of the superconducting vacuum tube is the evaporation section, and the upper end is the condensation section. The condensation section of the superconducting vacuum tube is inserted into the diversion pipe. The vaporized superconducting medium moves up to the condensation section, and water flows in a circulating manner in the diversion pipe, absorbing the heat of the condensation section. The cooled superconducting medium condenses into a liquid and flows back to the evaporation section.

[0003] For example, the Chinese published invention patent [Application No. 201610095142.X] discloses a new type of water-flowing anti-freezing flat solar collector, which includes a metal outer frame. An internally water-flowing heat collection diversion pipe is arranged inside the metal outer frame. The left and right ends of the heat collection diversion pipe are provided with a liquid inlet and a liquid outlet. A plurality of slots are formed in the middle section of the diversion pipe wall and extend out of the heat collection diversion pipe. A plurality of superconducting vacuum tubes pass through the slots and are connected to the heat collection diversion pipe. The superconducting vacuum tube contains a superconducting medium. The superconducting vacuum tube is divided into a condensation section and an evaporation section, and both ends are sealed and evacuated; the condensation section of the superconducting vacuum tube penetrates into the slot formed in the heat collection diversion pipe, and the other end is provided with an evaporation section, which is installed inside the metal frame. Existing flat heat collection devices are similar in structure to the above-mentioned solar collector. After the ambient temperature drops below zero, the water in the diversion pipe stops flowing, and the volume of the ice formed is larger than that of water, which will cause the space inside the diversion pipe to expand to a certain extent, resulting in the pipeline cracking and damaging the flat heat collection device. To solve the above problems, the current main solution is to add antifreeze in the diversion pipe, but the antifreeze needs to be replenished regularly, and the antifreeze is prone to blockage and caking during flow.

[0004] Another example is a Chinese published utility model patent [Application No. 202320969625.3], which introduces an anti-freezing solar flat heat pipe collector. To solve the problem of the bursting of the metal flow channel with water flowing inside the heat collection flat plate, a silica gel airbag tube is placed inside the metal flow channel. When the water inside the metal flow channel freezes, the silica gel airbag tube shrinks, absorbing the expanded volume after the water freezes, and preventing the metal flow channel from being damaged due to the expansion of the water after freezing. However, the silica gel airbag tube is prone to aging, and the manufacturing cost is high and the technical difficulty is great when the silica gel airbag tube is inserted into the metal tube. Summary of the Invention

[0005] The object of the present invention is to address the above problems existing in the prior art, and a non-powered phase-change vaporization flat-plate solar water heater is proposed. The heat collection flat plate uses a low-temperature-resistant phase-change heat-conducting medium for heat transfer to avoid freezing of the heat-conducting water and bursting of the pipeline.

[0006] The object of the present invention can be achieved by the following technical solutions: A non-powered phase-change vaporization flat-plate solar water heater, including a heat preservation water tank and a heat collection flat plate. The inner cavity of the heat preservation water tank is filled with heat-conducting water, and a heat exchange tube penetrates horizontally through the heat preservation water tank. It is characterized in that a closed copper straight tube and a closed header flow channel are fixed in the heat collection flat plate. The copper straight tube and the header flow channel are filled with an easily vaporizable phase-change heat-conducting medium. The end of the copper straight tube has a heat dissipation head inserted into the header flow channel, and the middle of the header flow channel has a condensing head protruding upward through the heat collection flat plate. The heat preservation water tank has a heat absorption head connected to the inner cavity, and a heat exchange component for heat exchange is connected between the condensing head and the heat absorption head.

[0007] Further, the heat exchange component includes a heat-conducting rod. The inside of the heat absorption head is hollow, and both the end faces of the condensing head and the heat absorption head have slots for the ends of the heat-conducting rod to be inserted. The heat-conducting rod is tightly fitted with the slots.

[0008] The heat preservation water tank is filled with heat-conducting water. Since the heat absorption head is connected to the heat preservation water tank, the heat absorption head is also filled with heat-conducting water. After the heat-conducting rod is installed, the heat of the condensing head can be transferred to the heat absorption head. Since the slots wrap the ends of the heat-conducting rod, the contact area is large and the heat conduction efficiency is high. During installation, only need to align the heat-conducting rod with the slots, and then push the heat collection flat plate upward to clamp the heat-conducting rod.

[0009] Further, the heat-conducting rod is a solid copper rod, and the outer wall of the middle part of the copper rod is wrapped with a heat-insulating protective layer, and the heat-insulating protective layer is made of sponge material. The heat-insulating protective layer can protect the heat-conducting rod, prevent the copper rod from rusting, and can also prevent the heat from being dissipated when the copper rod conducts heat by contacting the outside air to a certain extent.

[0010] Further, as another solution, the heat exchange component includes a silica gel sleeve and a heat-conducting cap. The heat absorption head is a water outlet pipe communicating with the inner cavity of the heat preservation water tank. The heat-conducting cap is sleeved on the condensing head, and both ends of the silica gel sleeve are respectively sleeved on the heat absorption head and the heat-conducting cap.

[0011] Further, the heat-conducting cap has a retaining edge, and the retaining edge is closely attached to the inner wall of the silica gel sleeve.

[0012] Further, the heat-conducting cap is made of copper.

[0013] Further, clamping rings are respectively sleeved at both ends of the silica gel sleeve. The clamping rings improve the sealing effect, prevent the heat-conducting water in the heat preservation water tank from overflowing from the gap between the heat absorption head and the silica gel sleeve, and also prevent the influence of the external temperature on the heat-conducting water in the heat absorption head, avoiding the heat-conducting water in the heat absorption head from freezing and bursting at low temperatures.

[0014] Further, the header flow channel is in a herringbone shape and the inclination angles of the two legs are 5° to 15°. Connecting holes for inserting the heat dissipation head are formed on the legs of the header flow channel, and the contact part between the heat dissipation head and the connecting holes is sealed by welding.

[0015] Further, the inside of the purple copper straight pipe is evacuated and the phase change heat-conducting medium only accounts for 10% to 15% of the internal volume.

[0016] Further, the inside of the header flow channel is evacuated and the phase change heat-conducting medium only accounts for 10% to 15% of the internal volume.

[0017] Further, the phase change heat-conducting medium is one of hexane, acetone, ethanol, methanol, toluene, pure water, and naphthalene.

[0018] Working principle: The heat absorption plate in the heat collection flat plate absorbs solar energy and converts it into heat energy. After the heat energy is absorbed by the purple copper straight pipe, the phase change heat-conducting medium inside it is vaporized. The vaporized phase change heat-conducting medium rises along the purple copper straight pipe to the heat dissipation head. The heat dissipation head transfers the heat energy to the phase change heat-conducting medium in the header flow channel. The vaporized phase change heat-conducting medium rises to the condensation head. The condensation head transfers it to the heat absorption head through the heat exchange component. The heat absorption head heats the heat-conducting water in the heat preservation water tank. The heat exchange pipe is in full contact with the heat-conducting water and heats the flowing domestic water in the heat exchange pipe. The heated domestic water can be directly used by people.

[0019] Compared with the prior art, the non-powered phase change vaporization flat solar water heater has the following advantages:

[0020] 1. The phase change heat-conducting medium is a superconducting material that can be vaporized at 18°C to 25°C and will not freeze even at -70°C. The exposed diversion pipe is cancelled, and the heat exchange component is directly used for heat exchange with the heat-conducting water in the heat preservation water tank to achieve the low-temperature resistance function.

[0021] 2. The silica gel sleeve wraps the heat absorption head and the heat-conducting cap. The silica gel sleeve has the same heat preservation effect as the heat preservation water tank, avoiding freezing the heat-conducting water in a low-temperature environment and causing the silica gel sleeve or the heat absorption head to burst.

[0022] 3. When the heat exchange component is a heat conduction rod, liquid heat conduction is cancelled, and a solid copper rod is used to achieve the heat exchange between the heat collection flat plate and the heat preservation water tank. All the heat conduction water is in the heat preservation water tank. The heat exchange component will not be damaged and is not afraid of the influence of low temperature environment. The heat insulation protection layer outside the heat conduction rod can also protect the copper rod to avoid heat dissipation and rust; the heat conduction rod is connected by a plug-in method, and the installation and disassembly are relatively fast and convenient.

[0023] 4. There is no heat conduction water in the heat collection flat plate, so it will not freeze and burst in a low temperature environment. Due to the low temperature resistance of the phase change heat conduction medium, it will not freeze above -70°C. Therefore, the purple copper straight pipe and the header flow channel are not easy to burst.

[0024] 5. The heat collection flat plate of this application is a phase change flat plate that does not pass water or antifreeze, has a long service life, avoids the operation of frequently replenishing antifreeze, and has low maintenance costs.

[0025] 6. The purple copper straight pipe and the header flow channel in the heat collection flat plate are of a closed structure, and the internal phase change heat conduction medium does not contact the outside world, does not produce dirt, and will not scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic structural diagram of a non-powered phase change vaporization flat plate solar water heater in Embodiment 1.

[0027] Figure 2 is a schematic structural diagram of a non-powered phase change vaporization flat plate solar water heater in Embodiment 2.

[0028] Figure 3 is an exploded view of the heat exchange component in Embodiment 1.

[0029] Figure 4 is Figure 2 an enlarged view at A.

[0030] In the figure, 1. Heat preservation water tank; 2. Heat collection flat plate; 3. Heat exchange tube; 4. Purple copper straight pipe; 41. Heat dissipation head; 5. Header flow channel; 51. Condensation head; 6. Heat absorption head; 7. Heat conduction rod; 71. Heat insulation protection layer; 8. Silicone sleeve; 9. Heat conduction sleeve cap; 91. Baffle edge; 10. Clamp ring; 11. Phase change heat conduction medium; 12. Slot. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] The following are specific embodiments of the present invention in combination with the drawings, and the technical solutions of the present invention will be further described, but the present invention is not limited to these embodiments.

[0032] Embodiment 1

[0033] As Figure 1 , Figure 3As shown in the figure, this non-powered phase-change vaporization flat-plate solar water heater includes a heat preservation water tank 1 and a heat collection flat plate 2. The inner cavity of the heat preservation water tank 1 is filled with heat-conducting water. A heat exchange tube 3 runs horizontally through the heat preservation water tank 1. A closed copper straight tube 4 and a closed header flow channel 5 are fixed inside the heat collection flat plate 2. The copper straight tube 4 and the header flow channel 5 are filled with an easily vaporizable phase-change heat-conducting medium 11. The end of the copper straight tube 4 has a heat dissipation head 41 inserted into the header flow channel 5. The middle part of the header flow channel 5 has a condensing head 51 that protrudes upward through the heat collection flat plate 2. The heat preservation water tank 1 has a heat absorption head 6 connected to the inner cavity. A heat exchange component for heat exchange is connected between the condensing head 51 and the heat absorption head 6.

[0034] The heat exchange component includes a heat-conducting rod 7. The inside of the heat absorption head 6 is hollow. Both the end faces of the condensing head 51 and the heat absorption head 6 have slots 12 for the ends of the heat-conducting rod 7 to be inserted into, and the heat-conducting rod 7 is tightly fitted with the slots 12.

[0035] The heat preservation water tank 1 is filled with heat-conducting water. Since the heat absorption head 6 is connected to the heat preservation water tank 1, the heat absorption head 6 is also filled with heat-conducting water. After the heat-conducting rod 7 is installed, the heat of the condensing head 51 can be transferred to the heat absorption head 6. Since the slot 12 wraps the end of the heat-conducting rod 7, the contact area is large and the heat-conducting efficiency is high. During installation, only need to align the heat-conducting rod 7 with the slot 12, and then push the heat collection flat plate 2 upward to clamp the heat-conducting rod 7.

[0036] The heat-conducting rod 7 is a solid copper rod. The outer wall of the middle part of the copper rod is wrapped with a heat insulation protection layer 71, and the heat insulation protection layer 71 is made of sponge material. The heat insulation protection layer 71 can protect the heat-conducting rod 7, prevent the copper rod from rusting, and can also prevent the heat from being dissipated when the copper rod conducts heat by contacting the outside air to a certain extent.

[0037] The header flow channel 5 is in a herringbone shape and the inclination angles of the two legs are 5°. Connection holes for the heat dissipation head 41 to be inserted are opened on the legs of the header flow channel 5, and the contact part between the heat dissipation head 41 and the connection holes is sealed by welding. The inside of the copper straight tube 4 is evacuated and the phase-change heat-conducting medium 11 only accounts for 10% of the internal volume. The inside of the header flow channel 5 is evacuated and the phase-change heat-conducting medium 11 only accounts for 10% of the internal volume. The phase-change heat-conducting medium 11 is ethanol.

[0038] Working principle: The heat absorption plate in the heat collection flat plate 2 absorbs solar energy and converts it into heat energy. After the heat energy is absorbed by the purple copper straight pipe 4, the phase change heat conduction medium 11 inside it is vaporized. The vaporized phase change heat conduction medium 11 rises along the purple copper straight pipe 4 to the heat dissipation head 41. The heat dissipation head 41 transfers the heat energy to the phase change heat conduction medium 11 in the header flow channel 5. The vaporized phase change heat conduction medium 11 rises to the condensation head 51. The condensation head 51 transfers it to the heat absorption head 6 through the heat conduction rod 7. The slot 12 of the heat absorption head 6 extends into the heat preservation water tank 1, increasing the contact area between the heat conduction rod 7 and the heat absorption head 6, and also increasing the contact surface between the heat absorption head 6 and the heat conduction water. The heat exchange tube 3 is in full contact with the heat conduction water, heating the flowing domestic water in the heat exchange tube 3. The heated domestic water can be directly used by people.

[0039] Embodiment 2

[0040] As Figure 2 , Figure 4 shown, the difference lies in the structure of the heat exchange component. The heat exchange component of this embodiment includes a silica gel sleeve 8 and a heat conduction cap 9. The heat absorption head 6 is a water outlet pipe communicating with the inner cavity of the heat preservation water tank 1. The heat conduction cap 9 is sleeved on the condensation head 51, and both ends of the silica gel sleeve 8 are respectively sleeved on the heat absorption head 6 and the heat conduction cap 9. The heat conduction water in the heat preservation water tank 1 enters the silica gel sleeve 8 through the heat absorption head 6.

[0041] The heat conduction cap 9 has a retaining edge 91, and the retaining edge 91 is in close fit with the inner wall of the silica gel sleeve 8. The heat conduction cap 9 is made of copper.

[0042] Both ends of the silica gel sleeve 8 are respectively sleeved with a clamp ring 10. The clamp ring 10 improves the sealing effect, prevents the heat conduction water in the heat preservation water tank 1 from overflowing from the gap between the heat absorption head 6 and the silica gel sleeve 8, and can also prevent the influence of the external temperature on the heat conduction water in the heat absorption head 6, avoiding the heat conduction water in the heat absorption head 6 from freezing and bursting at low temperatures.

[0043] Working principle: The heat absorption plate in the heat collection flat plate 2 absorbs solar energy and converts it into heat energy. After the heat energy is absorbed by the purple copper straight pipe 4, the phase change heat conduction medium 11 inside it is vaporized. The vaporized phase change heat conduction medium 11 rises along the purple copper straight pipe 4 to the heat dissipation head 41. The heat dissipation head 41 transfers the heat energy to the phase change heat conduction medium 11 in the header flow channel 5. The vaporized phase change heat conduction medium 11 rises to the condensation head 51. The outside of the heat conduction cap 9 is surrounded by the heat conduction water. The condensation head 51 transfers it to the heat conduction water in the silica gel sleeve 8 through the heat conduction cap 9. The heat conduction water in the heat absorption head 6 and the silica gel sleeve 8 is mixed with the heat conduction water in the heat preservation water tank 1 and then heated. The heat exchange tube 3 is in full contact with the heat conduction water, heating the flowing domestic water in the heat exchange tube 3. The heated domestic water can be directly used by people.

[0044] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Those skilled in the art to which the present invention pertains can make various modifications or supplements to the described specific embodiments or use similar means for substitution, but will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. A non-powered phase-change vaporization flat-plate solar water heater, comprising a heat-insulating water tank (1) and a heat-collecting flat plate (2), wherein the inner cavity of the heat-insulating water tank (1) is filled with heat-conducting water, and a heat-exchange pipe (3) is horizontally passed through the heat-insulating water tank (1), characterized in that: A closed copper straight tube (4) and a closed manifold flow channel (5) are fixed in the heat collecting plate (2); an easily vaporizable phase-change heat conducting medium (11) is injected into the copper straight tube (4) and the manifold flow channel (5); a heat dissipation head (41) is inserted into the manifold flow channel (5) at the end of the copper straight tube (4); a condensation head (51) protruding upward and passing through the heat collecting plate (2) is provided in the middle of the manifold flow channel (5); a heat absorbing head (6) connected to the inner cavity is provided on the heat preservation water tank (1); a heat exchange component for heat exchange is connected between the condensation head (51) and the heat absorbing head (6).

2. The unpowered phase change vaporization flat-plate solar water heater according to claim 1, characterized in that: The heat exchange component comprises a heat conducting rod (7), the interior of the heat absorbing head (6) is hollow, and the end surfaces of the condensing head (51) and the heat absorbing head (6) are provided with a slot (12) for inserting the end of the heat conducting rod (7), and the heat conducting rod (7) is tightly matched with the slot (12).

3. The unpowered phase change vaporization flat-plate solar water heater according to claim 2, characterized in that: The heat conducting rod (7) is a solid copper rod, and the outer wall of the middle part of the copper rod is wrapped with a heat insulating protective layer (71), and the heat insulating protective layer (71) is made of sponge material.

4. The unpowered phase change vaporization flat-plate solar water heater according to claim 1, characterized in that: The heat exchange component comprises a silicone sleeve (8) and a heat-conducting sleeve cap (9); the heat-absorbing head (6) is a water outlet pipe connected to the inner cavity of the heat-insulating water tank (1); the heat-conducting sleeve cap (9) is sleeved on the condensing head (51); and the two ends of the silicone sleeve (8) are respectively sleeved on the heat-absorbing head (6) and the heat-conducting sleeve cap (9).

5. The unpowered phase change vaporization flat-plate solar water heater according to claim 4, characterized in that: The heat-conducting sleeve cap (9) has a retaining edge (91), and the retaining edge (91) is tightly fitted with the inner wall of the silicone sleeve (8).

6. The unpowered phase-change vaporization flat-plate solar water heater according to claim 5, characterized in that: The heat-conducting sleeve cap (9) is made of copper.

7. The unpowered phase-change vaporization flat-plate solar water heater according to claim 6, characterized in that: The two ends of the silicone sleeve (8) are respectively sleeved with clamp rings (10).

8. The unpowered phase-change vaporization flat-plate solar water heater according to claim 1, characterized in that: The manifold flow channel (5) is in a herringbone shape and the inclination angles of the two legs are 5° to 15°. The legs of the manifold flow channel (5) are provided with connection holes for inserting the heat sink (41). The contact between the heat sink (41) and the connection hole is sealed by welding.

9. The unpowered phase-change vaporization flat-plate solar water heater according to claim 8, characterized in that: The copper straight tube (4) is evacuated and the phase-change heat-conducting medium (11) only occupies 10% to 15% of the internal volume; the manifold flow channel (5) is evacuated and the phase-change heat-conducting medium (11) only occupies 10% to 15% of the internal volume.

10. The unpowered phase-change vaporization flat-plate solar water heater according to claim 9, characterized in that: The phase-change heat-conducting medium (11) is a phase-change heat-conducting medium selected from the group consisting of hexane, acetone, ethanol, methanol, toluene, pure water, and naphthalene.

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