A solar interface vapor production system based on bistable structure

Abstract

The application provides a solar interface vapor preparation system based on a bistable structure and belongs to the technical field of solar vapor generators. The system comprises an interface evaporation assembly and a bistable support assembly. The interface evaporation assembly comprises a photothermal conversion material, a buoyant body and a water transport material. The bottom end of the middle part of the photothermal conversion material is in contact with the water transport material. The lower end of the water transport material extends downward and passes through the middle part of the buoyant body. The bistable support assembly comprises a bistable structure and a plurality of springs. The bistable structure is arranged between the photothermal conversion material and the buoyant body. The water transport material passes through the bistable structure. One end of each of the plurality of springs is connected to one side of the bistable structure. The other end of each of the plurality of springs is arranged on the buoyant body. The system can make the evaporator produce violent shaking or oscillation under slight disturbance, so that salt crystals fall off.

Description

Technical Field

[0001] This invention relates to the field of solar steam generator technology, and more particularly to a solar interface steam preparation system based on a bistable structure. Background Technology

[0002] Seawater desalination, as a key technological approach to solving the global water crisis, is facing real challenges such as high energy consumption and high operating costs. Among the many seawater desalination technologies, solar-driven interfacial evaporation technology has attracted much attention due to its advantages such as low energy consumption and environmental friendliness.

[0003] Solar interface evaporation technology can convert solar energy into heat energy and concentrate it on the evaporation surface, effectively reducing the conduction of heat energy to the liquid, thereby significantly reducing energy loss and improving the efficiency of freshwater production.

[0004] As the evaporation process continues, the salt concentration inside the evaporator gradually approaches saturation, eventually leading to the deposition of a large amount of salt crystals at the photothermal interface. This hinders light absorption and reduces evaporation performance, which is a key bottleneck limiting the long-term stable operation of the evaporator. Therefore, timely removal of the accumulated salt crystals at the photothermal interface is crucial for maintaining a stable evaporation rate. Summary of the Invention

[0005] The purpose of this invention is to provide a solar interface steam preparation system based on a bistable structure, solving the technical problems mentioned in the background art. The system of this invention enables the evaporator to generate violent shaking or oscillation under minute disturbances, causing salt crystals to detach.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A solar interfacial vapor preparation system based on a bistable structure includes an interfacial evaporation component and a bistable support component; The interface evaporation component includes a photothermal conversion material, a buoyancy body, and a water conveying material. The bottom end of the middle part of the photothermal conversion material is in contact with the water conveying material, and the lower end of the water conveying material extends downward and passes through the middle part of the buoyancy body. The bistable support assembly includes a bistable structure and several springs. The bistable structure is disposed between the photothermal conversion material and the buoyancy body. The water conveying material passes through the bistable structure. One end of each of the several springs is connected to one side of the bistable structure, and the other end of each of the several springs is disposed on the buoyancy body.

[0007] Furthermore, the bistable structure includes several cantilever beams and fixed ends. The upper ends of the several cantilever beams are in contact with the photothermal conversion material, and the lower ends of the several cantilever beams are disposed between two fixed ends. The fixed ends are disposed on the buoyancy body, and the water conveying material passes through the two fixed ends in sequence.

[0008] Furthermore, one end of each of the plurality of springs is connected to one end of a plurality of cantilever beams, and the other end of the plurality of springs is disposed on the buoyancy body. When the cantilever beam elastically jumps, the springs can provide rebound support for the cantilever beam.

[0009] Furthermore, the photothermal conversion material is configured with a petal-shaped structure, and the photothermal conversion material is a porous material with high light absorption.

[0010] Furthermore, the high absorbance porous material is one or more of aerogel, hydrogel, carbon felt, or carbonized biomass material that are flexibly loaded.

[0011] Furthermore, a groove is provided in the middle of the buoyancy body, the fixed end is provided in the groove, and a through hole is provided in the middle of both the fixed end and the groove, through which the water conveying material passes.

[0012] Furthermore, the buoyancy body is polyethylene foam or a material that can provide sufficient buoyancy.

[0013] Furthermore, the water conveying material is one of the following: cotton wool, cotton swabs, hemp rope, or hemp thread.

[0014] Furthermore, the cantilever beam is configured as an outwardly concave arc-shaped structure, and the cantilever beam is made of brass sheet or stainless steel sheet.

[0015] Furthermore, the method for preparing the bistable structure includes the following steps: (1) Select several pairs of slender brass or stainless steel sheets as cantilever beams, use adhesive film to evenly bond them between two 1mm thick aluminum plates and tighten them with clamps. (2) Carefully align the lower ends of the opposite cantilever beams on the table, glue them together with adhesive film and tighten them with clips; (3) Place the entire component into an oven and cure it at 120°C for 90 minutes. After curing, remove the component and remove the clamps to obtain the finished bistable structure.

[0016] The present invention, by adopting the above-described technical solution, has the following beneficial effects: 1. The system of the present invention adopts a purely mechanical structure, without the need for electric fields, magnetic fields, smart materials or external electrical control. It can achieve automatic desalination by relying on the accumulated weight of salt and the elastic jump characteristics of the structure itself. It can also use environmental disturbances such as natural wind fields, water surface waves, and water flow impact to assist in triggering desalination, which greatly reduces the structural complexity and manufacturing cost of the interface evaporation system. It is suitable for outdoor, electricity-free, long-term unattended seawater desalination scenarios, and its stability and environmental adaptability are significantly improved.

[0017] 2. When the system of the present invention is applied in saline water, it can actively remove existing salt crystals and can transform external disturbances into mechanical vibrations that are conducive to the shedding of salt crystals in windy and wavey environments or floating conditions on the water surface, so as to avoid the performance degradation of the system due to salt crystals. It can be used stably for a long time in the fields of seawater desalination, drinking water purification and sewage treatment.

[0018] 3. The system of the present invention can flexibly adjust the triggering force and jump amplitude through size, stiffness and geometric configuration, and can be adapted to evaporation interfaces of different sizes, materials and shapes. It can be matched according to salt crystallization rate, water salinity and load weight. It has strong versatility and is easy to modularize and array.

[0019] 4. While achieving self-cleaning, the system of the present invention can simultaneously induce gas-liquid interface instability and oscillation through the shaking process triggered by the bistable structure. This effectively breaks the static liquid film distribution formed by capillary action inside the photothermal porous medium, expands the area of ​​the thin liquid film region on the meniscus inside the porous medium, enhances the local heat transfer coefficient, and thus improves the evaporation preparation efficiency. This design ingeniously converts environmental disturbance energy (such as wind energy and wave energy) into beneficial mechanical vibration, realizing efficient energy utilization and functional coupling, and further improving the overall energy conversion efficiency of the system. Attached Figure Description

[0020] Figure 1 This is a disassembled schematic diagram of the solar interface vapor preparation system of the present invention; Figure 2 This is a schematic diagram of the spring installation in the solar interface vapor preparation system of the present invention; Figure 3 This is a schematic diagram of the operation of the solar interface vapor preparation system of the present invention.

[0021] In the attached diagram, 1-photothermal conversion material, 2-buoyancy body, 3-water conveying material, 4-cantilever beam, 5-fixed end, 6-spring, 7-groove, 8-through hole. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments. However, it should be noted that many details listed in the specification are merely to provide the reader with a thorough understanding of one or more aspects of the present invention, and these aspects of the invention can be implemented even without these specific details.

[0023] like Figure 1-3As shown, a solar interface steam preparation system based on a bistable structure includes an interface evaporation component and a bistable support component. The interface evaporation component includes a photothermal conversion material 1, a buoyancy body 2, and a water conveying material 3. The bottom end of the middle part of the photothermal conversion material 1 is in contact with the water conveying material 3. The photothermal conversion material 1 is supported by the bistable support component. The photothermal conversion material 1 is used to absorb sunlight and convert it into heat. The lower end of the water conveying material 3 extends downward and passes through the middle part of the buoyancy body 2. The water conveying material 3 extends downward and contacts the water body, transporting water to the upper photothermal conversion interface. The buoyancy body 2 is used to provide buoyancy. The bistable support component includes a bistable structure based on cantilever beam warping and several springs 6. The bistable structure is disposed between the photothermal conversion material 1 and the buoyancy body 2. The water conveying material 3 is disposed through the bistable structure. One end of each of the several springs 6 is connected to one side of the bistable structure, and the other end of each of the several springs 6 is disposed on the buoyancy body 2. In this invention, the bistable support component is designed to induce desalination by natural environmental disturbances when the salt crystallization load approaches the critical triggering force; the natural environmental disturbances include one or more of the following: aerodynamic forces generated by wind blowing across the surface of the photothermal conversion material 1, heave, swaying or pitching disturbances caused by waves when the device floats on the water surface, and water flow or water surface vibration.

[0024] like Figure 1-2As shown, the bistable structure includes several cantilever beams 4 and fixed ends 5. The upper ends of the cantilever beams 4 are in contact with the photothermal conversion material 1, and the lower ends of the cantilever beams 4 are positioned between two fixed ends 5. The fixed ends 5 are mounted on the buoyancy body 2, and the water conveying material 3 passes through the two fixed ends 5 sequentially. Each cantilever beam 4 is formed by gluing one end of a pair of slender brass or stainless steel sheets together. Their upper ends are overlapped and glued together, meaning the upper surface of one brass or stainless steel sheet is glued to the lower surface of the other brass or stainless steel sheet. The upper ends of the cantilever beams are overlapped and glued together, while the lower ends are separated at a small angle. The un-glued end is a free end. The free ends of the cantilever beams are glued between the pair of fixed ends 5. The specific bistable structure and materials in the bistable support assembly can be flexibly selected according to actual needs. A typical bistable support assembly is based on the warping of the cantilever beams. One end of each of the several springs 6 is connected to one end of each of the several cantilever beams 4. The springs 6 are welded to the top of the overlapping end of the cantilever beams 4. The other end of each of the several springs 6 is set on the buoyancy body 2. The lower end of the spring is inserted obliquely into the foam. The lower end of the spring 6 is fixed in the buoyancy body 2 according to the actual situation. Taking polyethylene foam as an example, the spring can be stuffed into the foam, or a barb can be welded and then hooked into the foam. The springs 6 are welded to the cantilever beams 4. When the cantilever beams 4 elastically jump, the springs 6 can provide rebound support for the cantilever beams 4. The cantilever beams of the bistable support assembly support the surface of the photothermal conversion material. When salt gradually accumulates on the surface of the photothermal conversion material, the gravitational load of salt crystallization causes the cantilever beams to enter a buckling or critical buckling state. At this time, wind, water waves, water flow impact, buoyancy body swaying, or micro-vibrations caused by its own evaporation process can all act as inducing factors to cause the cantilever beams to elastically jump or vibrate periodically, thereby shaking off the existing salt crystals on the photothermal conversion material. During this period, the gas-liquid interface of the photothermal conversion material is subjected to elastic jumps or periodic swaying disturbances. This dynamic process further expands the area of ​​the thin liquid film region on the meniscus inside the porous medium, induces periodic oscillations at the interface, improves local heat conduction performance, thereby optimizing heat transfer during the phase change process and ultimately achieving an increase in the evaporation rate.

[0025] In an embodiment of the present invention, the photothermal conversion material 1 is configured with a petal-shaped structure, having several petals. The photothermal conversion material 1 is a high-absorbency porous material. The high-absorbency porous material is one or more of aerogel, hydrogel, carbon felt, or carbonized biomass material that can be flexibly loaded. The buoyancy body 2 has a groove 7 in its middle, and the fixed end 5 is disposed in the groove 7. Both the fixed end 5 and the groove 7 have through holes 8 in their middle portions, through which the water conveying material 3 passes. The groove 7 is used to house the bistable structure, and the water conveying material 3 supplies water to the photothermal conversion material 1 through the through holes 8. The size and shape of the through holes 8 are set as needed, allowing the water conveying material 3 to pass through the holes of the fixed end 5 and the buoyancy body 2 simultaneously, thus delivering water to the photothermal conversion material 1. The buoyancy body 2 is polyethylene foam or a material that can provide sufficient buoyancy. The water conveying material 3 is one of cotton wool, cotton swabs, hemp rope, or hemp thread. The cantilever beam 4 is configured as an outwardly concave arc-shaped structure, and the cantilever beam 4 is made of brass sheet or stainless steel sheet.

[0026] In an embodiment of the present invention, the method for preparing the bistable structure includes the following steps: (1) Select several pairs of slender brass or stainless steel sheets as cantilever beams. To prevent the fixed end from deforming in subsequent operations, use adhesive film to evenly bond them between two 1mm thick aluminum plates and tighten them with clamps. (2) Carefully align the lower ends of the opposite cantilever beams on the table, ensuring that the midpoints coincide, glue them together with adhesive film and tighten them with clips; (3) Place the entire component into an oven and cure it at 120°C for 90 minutes. After curing, remove the component and remove the clamps to obtain the finished bistable structure.

[0027] Use appropriately sized dovetail clips, and set the curing time of the oven according to the adhesive film used to ensure that the cantilever beam is firm and reliable after curing.

[0028] System Principles The cantilever beam 4 of the bistable support assembly supports the lower surface of the photothermal conversion material 1. When salt gradually accumulates on the surface of the photothermal conversion material 1, the gravitational load of salt crystallization causes the cantilever beam 4 to be in a buckling or critical buckling state. When the photothermal conversion material 1 is displaced or vibrates due to the gravity of salt crystallization, wind disturbance, wave disturbance, water flow impact, buoyancy body 2 swaying, or the combined effect of the above factors, the cantilever beam 4 undergoes elastic jumps or periodic swaying, shaking off the existing salt crystals on the photothermal conversion material 1. During this period, the gas-liquid interface of the photothermal conversion material 1 is disturbed by elastic jumps or periodic swaying. This dynamic process further expands the area of ​​the thin liquid film region of the meniscus inside the porous medium, induces periodic oscillations at the interface, improves local heat conduction performance, thereby optimizing heat transfer during the phase change process and ultimately achieving an increase in the evaporation rate.

[0029] Example This embodiment provides a typical example of a solar interfacial vapor preparation system based on a bistable structure. The system includes an interfacial evaporation component and a bistable support component.

[0030] like Figure 1 As shown, the interface evaporation assembly includes a buoyancy body, a photothermal conversion material, and a water conveyance material. The buoyancy body is made of polyethylene foam, with a central groove and through-holes. The groove houses the bistable support assembly, and the through-holes allow the water conveyance material to pass through. The photothermal conversion material is carbon felt with high light absorption and a well-defined porous structure, cut into a six-petal flower shape. The water conveyance material is a cotton swab, its upper end passing through the holes in the buoyancy body and the bistable support assembly, and in close contact with the lower center of the carbon felt photothermal conversion material. Its lower end is immersed in the brine to be treated, continuously delivering the brine to the photothermal evaporation interface.

[0031] The bistable support assembly is a bistable structure based on cantilever beam warping. This typical structure employs six cantilever beams, each composed of six pairs of slender brass sheets. The upper ends of each pair of brass sheets are glued together with hot melt adhesive to form a cantilever beam, while the lower ends are glued between a pair of 1mm thick fixed ends. The fixed ends are securely placed within grooves in the buoyancy body. A spring is welded to the upper part of each cantilever beam, and the other end is inserted into foam for support. Petal-shaped carbon felt photothermal conversion material is placed above the six cantilever beams, with each petal supported by one cantilever beam. Figure 3 As shown, under sunlight, the carbon felt absorbs light energy and converts it into heat energy. Moisture transported via cotton swabs evaporates rapidly on the carbon felt surface. As evaporation continues, salt begins to crystallize and gradually accumulate at the edges of the carbon felt. When the salt weight increases to a certain level, the cantilever beam buckles or reaches a critical buckling state due to the increased load. In this state, the gravity of the salt crystals can trigger elastic buckling. Disturbances caused by wind blowing across the evaporation surface, wave heaves and swaying disturbances experienced when the device floats on water, water flow impacts, or micro-vibrations during evaporation can further induce buckling or swaying of the cantilever beam, causing the carbon felt photothermal conversion material above to vibrate, thus causing the salt crystals on its surface to detach. Simultaneously, the vibration induces instability and oscillation at the gas-liquid interface, expanding the area of ​​the thin liquid film region on the meniscus within the porous medium, enhancing the local heat transfer coefficient, and increasing the evaporation rate. Subsequently, under the restoring force of the spring, the cantilever beam returns to its original shape, and the system continues stable evaporation operations.

[0032] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A solar interfacial vapor preparation system based on a bistable structure, characterized in that: Includes an interface evaporation component and a bistable support component; The interface evaporation component includes a photothermal conversion material (1), a buoyancy body (2), and a water conveying material (3). The bottom end of the middle part of the photothermal conversion material (1) is in contact with the water conveying material (3), and the lower end of the water conveying material (3) extends downward and passes through the middle part of the buoyancy body (2). The bistable support assembly includes a bistable structure and several springs (6). The bistable structure is disposed between the photothermal conversion material (1) and the buoyancy body (2). The water conveying material (3) passes through the bistable structure. One end of each of the several springs (6) is connected to one side of the bistable structure, and the other end of each of the several springs (6) is disposed on the buoyancy body (2).

2. The solar interface vapor preparation system based on a bistable structure according to claim 1, characterized in that: The bistable structure includes several cantilever beams (4) and fixed ends (5). The upper ends of the several cantilever beams (4) are in contact with the photothermal conversion material (1), and the lower ends of the several cantilever beams (4) are located between two fixed ends (5). The fixed ends (5) are located on the buoyancy body (2), and the water conveying material (3) passes through the two fixed ends (5) in sequence.

3. The solar interface vapor preparation system based on a bistable structure according to claim 1, characterized in that: One end of each of the several springs (6) is connected to one end of each of the several cantilever beams (4), and the other end of each of the several springs (6) is set on the buoyancy body (2). When the cantilever beam (4) elastically jumps, the springs (6) can provide rebound support for the cantilever beam (4).

4. The solar interface vapor preparation system based on a bistable structure according to claim 1, characterized in that: The photothermal conversion material (1) is configured with a petal-shaped structure and is a porous material with high light absorption.

5. The solar interface vapor preparation system based on a bistable structure according to claim 4, characterized in that: The high absorbance porous material is one or more of aerogel, hydrogel, carbon felt, or carbonized biomass material that are flexibly loaded.

6. The solar interface vapor preparation system based on a bistable structure according to claim 1, characterized in that: The buoyancy body (2) has a groove (7) in the middle, the fixed end (5) is set in the groove (7), and both the fixed end (5) and the groove (7) have through holes (8) in the middle, through which the water conveying material (3) passes.

7. The solar interface vapor preparation system based on a bistable structure according to claim 1, characterized in that: The buoyancy body (2) is polyethylene foam or a material that can provide sufficient buoyancy.

8. The solar interface vapor preparation system based on a bistable structure according to claim 1, characterized in that: The water conveying material (3) is one of the following: cotton wool, cotton swabs, hemp rope, or hemp thread.

9. The solar interface vapor preparation system based on a bistable structure according to claim 1, characterized in that: The cantilever beam (4) is configured as an outwardly concave arc structure, and the cantilever beam (4) is made of brass sheet or stainless steel sheet.

10. A solar interface vapor preparation system based on a bistable structure according to claim 2, characterized in that: The method for preparing the bistable structure includes the following steps: (1) Select several pairs of slender brass or stainless steel sheets as cantilever beams, use adhesive film to evenly bond them between two 1mm thick aluminum plates and tighten them with clamps. (2) Carefully align the lower ends of the opposite cantilever beams on the table, glue them together with adhesive film and tighten them with clips; (3) Place the entire component into an oven and cure it at 120°C for 90 minutes. After curing, remove the component and remove the clamps to obtain the finished bistable structure.

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