Solar-driven interfacial seawater evaporation device based on garlic root biomimetic fabric

Abstract

This invention relates to the field of solar-powered seawater desalination technology, and in particular to a solar-driven seawater interface evaporation device based on garlic root-inspired biomimetic fabric. The device includes a photothermal layer and a water supply layer, which are integrally woven together and possess self-supporting properties after absorbing water. The photothermal layer includes a fabric substrate with vertically drawn pile tissue on its surface through a napping process. The water supply layer includes a garlic root-like biomimetic root system immersed in seawater, suspended on the side of the fabric substrate away from the pile tissue, arranged in an array to transfer seawater to the photothermal layer. This application can achieve precise water supply control, efficient photothermal conversion, and excellent heat localization, improving evaporation efficiency and system stability, while simplifying the structure, reducing costs, and enhancing maintenance and storage convenience.

Description

Technical Field

[0001] This invention relates to the field of solar-powered seawater desalination technology, and in particular to a solar-driven seawater interface evaporation device based on garlic root biomimetic fabric. Background Technology

[0002] Traditional seawater desalination technologies suffer from drawbacks such as high energy consumption, complex equipment, and high maintenance costs. In contrast, solar-driven interfacial evaporation (SDIE) has attracted significant attention due to its zero carbon emissions, simple equipment, and low operating costs. SDIE achieves efficient solar energy utilization by concentrating photothermal conversion at the gas-liquid interface. Among the diversified developments of SDIE technology, fabric-based interfacial evaporation has become a research hotspot due to its unique advantages. Fabrics themselves possess a porous structure and good flexibility; their micro- and nano-pores and fiber gaps can construct efficient water transport channels through capillary action. Furthermore, the fabric surface is easily modified to achieve multiple light scattering, enhancing photothermal capture capabilities. Moreover, it is inexpensive, easily scalable, and flexibly adaptable to different application scenarios.

[0003] However, existing fabric-based SDIE systems still have significant technical shortcomings, severely restricting their long-term stable operation and practical application: First, water supply control is difficult; insufficient water supply can easily lead to salt crystallization and blockage of water delivery channels, thereby reducing evaporation efficiency; excessive water supply will cause heat to diffuse into the water body, resulting in heat loss and affecting the photothermal conversion effect. Second, the integration of structure and function is insufficient; most systems require additional insulation layers, floating modules, and connecting components, which not only increases system complexity and manufacturing costs but also reduces the convenience of system maintenance and storage.

[0004] Therefore, this invention designs a solar-driven seawater interface evaporation device based on garlic root biomimetic fabric to solve the above-mentioned technical problems. Summary of the Invention

[0005] The purpose of this invention is to provide a solar-driven seawater interface evaporation device based on garlic root biomimetic fabric to solve the problems existing in the prior art.

[0006] To achieve the above objectives, the present invention provides the following solution: The present invention provides a solar-driven seawater interface evaporation device based on garlic root biomimetic fabric, comprising a photothermal layer and a water supply layer, wherein the photothermal layer and the water supply layer are woven together in an integrated manner and have self-supporting properties after absorbing water. The photothermal layer includes a fabric substrate, the surface of which is vertically drawn out with pile structure through a pile raising operation; The water supply layer includes a biomimetic root system immersed in seawater. The biomimetic root system is configured as a garlic root-shaped biomimetic tissue. The biomimetic root system is suspended on the side of the fabric substrate away from the pile tissue. The biomimetic root system is arranged in an array and transmits seawater to the photothermal layer.

[0007] Preferably, the photothermal layer and the water supply layer are integrally formed by a weft-laid wool weaving process.

[0008] Preferably, the villous tissue is composed of polymer fibers.

[0009] Preferably, the polymer fiber is polyethylene terephthalate fiber.

[0010] Preferably, the biomimetic root system comprises an array of hydrophilic yarns, which are suspended and fixed to the fabric substrate.

[0011] Preferably, the hydrophilic yarn is a natural fiber yarn rich in hydroxyl groups and having a microporous structure inside.

[0012] Preferably, the number and distribution density of the biomimetic root system array are configured to match the water supply rate of the water supply layer with the evaporation rate of the photothermal layer.

[0013] Preferably, a natural height difference is formed between the photothermal layer and the water supply layer, so that the evaporation interface of the device is separated from the water to be treated, and the low thermal conductivity of air forms a natural heat insulation structure to achieve the effect of heat localization.

[0014] Preferably, the molding process includes the following steps: Provide warp and weft yarns, and interweave the warp and weft yarns on a loom to form the fabric base; The pile structure is formed by lifting the weft yarns between adjacent warp yarns to the fabric surface to create a photothermal layer, and then introducing weft yarns to fix the pile structure. After each weft yarn is inserted, ramie yarn is suspended below the warp yarn to form a garlic root-like biomimetic root system, and then the biomimetic root system is fixed by the weft yarn; After weaving, the fabric is set and finished to stabilize its structure and properties; Repeat the above steps to complete the weaving of the entire device.

[0015] Preferably, the hydrophilic yarn is bonded to the fabric substrate through a weaving fixing structure to achieve synchronous forming of the photothermal layer pile and the water supply layer array.

[0016] Compared with existing technologies, this invention has the following advantages and technical effects: This application provides a solar-driven seawater interface evaporation device based on garlic root biomimetic fabric. The photothermal layer and water supply layer are integrated into a single fabric, eliminating the need for additional insulation layers, floating modules, or connecting components. It is self-supporting after absorbing water, significantly simplifying the system structure, reducing manufacturing costs, and improving maintenance and storage convenience. The vertically extended pile structure on the fabric substrate surface increases the light reflection path, improves light capture efficiency, and achieves highly efficient photothermal conversion. The garlic root-shaped biomimetic root array utilizes capillary action to transfer seawater to the photothermal layer, achieving a continuous water supply. The biomimetic root system is suspended on the side of the fabric substrate away from the pile structure, creating a natural height difference that separates the evaporation interface from the water to be treated. The low thermal conductivity of the fiber yarn forms a natural insulation structure, effectively preventing heat diffusion into the water and achieving excellent heat localization. This design tightly integrates the photothermal layer and water supply layer through a unified weaving process, ensuring the structural integrity and stability. Simultaneously, an array of biomimetic root systems achieves a dynamic balance between water supply and evaporation rates, effectively solving the challenge of water supply regulation. The optimized number and density of the biomimetic root array, based on Darcy's law, allows the water supply layer to precisely match the evaporation demands of the photothermal layer, avoiding salt crystallization due to insufficient water supply or heat loss caused by excessive water supply. Using natural fiber yarns rich in hydroxyl groups and possessing a microporous structure as the biomimetic root system, the water transport efficiency is improved through physical structural optimization, achieving long-term stable operation. The entire device employs a full woven fabric structure, conforming to green manufacturing principles, and possesses excellent corrosion resistance, mechanical strength, and washability. It can stably produce freshwater that meets drinking water standards and is suitable for various application scenarios. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 This is a schematic diagram of the solar-driven seawater interface evaporation device based on garlic root biomimetic fabric of the present invention. In the diagram: 1. Photothermal layer; 2. Bionic root system; 3. Water storage tank; 4. Seawater; 5. Water supply layer. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] Reference Figure 1 As shown, this embodiment provides a solar-driven seawater interface evaporation device based on garlic root biomimetic fabric, including a photothermal layer 1 and a water supply layer 5. The photothermal layer 1 and the water supply layer 5 are woven together and have self-supporting properties after absorbing water. Photothermal layer 1 includes a fabric substrate, the surface of which a pile structure is vertically drawn out through a pile raising operation; The water supply layer 5 includes a biomimetic root system 2 immersed in seawater 4. The biomimetic root system 2 is configured as a garlic root-shaped biomimetic tissue. The biomimetic root system 2 is suspended on the side of the fabric substrate away from the pile tissue. The biomimetic root system 2 is arranged in an array and transmits the seawater 4 to the photothermal layer 1.

[0021] To address the aforementioned issues, this application proposes a solar-driven seawater interface evaporation device based on garlic root biomimetic fabric. The core idea is to abandon the traditional approach of relying on external structures for insulation and support, and instead use an integrated weaving process to construct a single, physically coupled, and functionally synergistic fabric entity from an upper structure with photothermal conversion capabilities and a lower structure with biomimetic water-absorbing capabilities. Specifically, the photothermal layer 1 forms a vertical pile structure through napping to enhance the light path and surface area, while the water supply layer 5 mimics the shape of a garlic root with a suspended array structure to achieve capillary-driven, directional, and controllable water delivery. The two layers are spatially fixed and mechanically interdependent; after water absorption, fiber swelling and structural tension spontaneously form a stable, self-supporting configuration, thus simultaneously solving the triple challenges of water supply compatibility, heat localization, and structural simplicity without introducing additional components. This application provides a solar-driven seawater interface evaporation device based on garlic root-inspired biomimetic fabric. The device integrates the photothermal layer 1 and the water supply layer 5 through a single weave, eliminating the need for additional insulation layers, floating modules, or connecting components. It is self-supporting after absorbing water, significantly simplifying the system structure, reducing manufacturing costs, and improving maintenance and storage convenience. The vertically extended pile structure on the fabric substrate surface increases the light reflection path, improves light capture efficiency, and achieves highly efficient photothermal conversion. An array of garlic root-shaped biomimetic roots 2 utilizes capillary action to transfer seawater 4 to the photothermal layer 1, ensuring a continuous water supply. The biomimetic roots 2 are suspended on the side of the fabric substrate away from the pile structure, creating a natural height difference that separates the evaporation interface from the water to be treated. The low thermal conductivity of the fiber yarn forms a natural insulation structure, effectively preventing heat diffusion into the water and achieving excellent heat localization. This design tightly integrates the photothermal layer 1 and the water supply layer 5 through an integrated weaving process, ensuring the integrity and stability of the structure. Simultaneously, the arrayed biomimetic root system 2 achieves a dynamic balance between water supply and evaporation rates, effectively solving the problem of water supply regulation. The optimized number and distribution density of the biomimetic root system 2 array, based on Darcy's law, allows the water supply layer 5 to precisely match the evaporation requirements of the photothermal layer 1, avoiding salt crystallization due to insufficient water supply or heat loss caused by excessive water supply. Natural fiber yarns rich in hydroxyl groups and possessing a microporous structure serve as the biomimetic root system 2, improving water transport efficiency through physical structure optimization and achieving long-term stable operation. The entire device utilizes a full woven fabric structure, conforming to green manufacturing principles, and possesses excellent corrosion resistance, mechanical strength, and washability. It can stably produce freshwater that meets drinking water standards and is suitable for various application scenarios.

[0022] In one embodiment of the present invention, an integrated double-layer biomimetic architecture is constructed, which takes the fabric body as the sole carrier, the warp and weft interlacing as the structural skeleton, and pile raising and hanging as functional shaping means. This architecture internalizes the four functions of light absorption, water transport, heat localization and structural support, which are traditionally designed separately, into the physical structure of a single fabric. Through the spatial misalignment, mechanical interlocking and transport coupling of the pile tissue and garlic root-like root system, the functional integration of one material with four functions is achieved. When the device is placed on the surface of seawater 4, the biomimetic root system 2 first rapidly absorbs water through capillary action and transports it upward along the yarn; the water passes through the fabric substrate and enters the internal pores of the villous tissue of the photothermal layer 1; under sunlight, the villous tissue significantly improves the photon capture efficiency due to its high specific surface area and multiple light scattering effect, and the light energy is converted into heat energy and localized on the villous surface and near-surface thin layer; due to the natural height difference between the photothermal layer 1 and the water supply layer 5, the evaporation interface is located at the top of the villous tissue and is separated from the main body of seawater below by fiber yarns. The extremely low thermal conductivity of the fiber yarns forms a natural heat insulation barrier, inhibiting the longitudinal conduction of heat to the water body; at the same time, the water vaporizes on the villous surface and the steam escapes rapidly, while the unevaporated water is continuously replenished under the drive of capillary force, thus forming a closed-loop working link of water absorption-water transport-light absorption-heat collection-evaporation.

[0023] In one embodiment of the present invention, the garlic root-like biomimetic root system 2 refers to a cluster-like branching shape, with each cluster consisting of 3-7 parallel or slightly divergent hydrophilic yarns. Each yarn is 40mm-70mm long and 0.3mm-0.8mm in diameter, with its ends naturally spreading out to form micro-whisker-like tips. The biomimetic root system 2 is suspended, meaning that its upper end is fixed to the warp and weft interlacing node on the lower surface of the fabric substrate, while its lower end hangs freely into the seawater 4 without contacting the bottom of the container, thereby maintaining an air gap between the root system and the water to avoid short circuits in heat conduction.

[0024] In one embodiment of the present invention, the length of each yarn is preferably 50 mm.

[0025] Further optimization of the design resulted in the photothermal layer 1 and the water supply layer 5 being integrally formed using a weft-laid knitting process. This integrated knitting of the photothermal layer 1 and the water supply layer 5 avoids the risk of interface weakening associated with step-by-step assembly. It contains no supporting frames, floats, adhesive layers, or mechanical fasteners independent of the fabric itself. After absorbing water, it possesses self-supporting properties. This self-supporting property stems from the hydration and swelling of the fibers after water absorption, generating anisotropic tension within the warp and weft interlacing structure, resulting in an upwardly arched curved surface. This shape remains stable under the balance of gravity and surface tension, allowing it to detach from external support and float independently on the water surface.

[0026] In a further optimized design, the pile structure is composed of polymer fibers. The pile structure is a vertically erected structure made of polymer fibers, its function being to form a photothermal interface with a high specific surface area and multiple light scattering capabilities, used to capture sunlight and achieve localized heating at the water-air interface. The pile structure is vertically drawn from the surface of the fabric substrate through a pile-forming process, and its height can be set according to the actual light intensity, ambient humidity, and evaporation requirements. In this application, the polymer fibers serve as the photothermal conversion material, forming an integrated light absorption and heat transfer unit, avoiding localized overheating or uneven light absorption.

[0027] Further optimization of the design resulted in the use of polyethylene terephthalate (PET) fiber as the polymer fiber. The selection of PET fiber was based on a balance of mechanical strength, water resistance, thermal stability, and compatibility with photothermal conversion materials. The overall solar energy absorption rate reached ≥98.5%, while maintaining good spinnability and weaving adaptability. This efficiently converts incident solar photon energy into heat energy, which is then rapidly conducted through the fiber body to the contact area between the fiber tip and the surface water film, thereby enhancing the driving force for interfacial evaporation.

[0028] In one embodiment of the present invention, when sunlight shines on the surface of the fluff, the doped photothermal conversion material preferentially absorbs broadband photons, excites electron transitions, and releases heat energy in a non-radiative relaxation manner. This heat diffuses rapidly along the axial and radial directions of the polymer fiber matrix, causing the temperature of the entire fluff to rise uniformly. A significant temperature gradient is formed between the heated fluff surface and the thin layer of seawater adsorbed on it, driving water molecules to accelerate phase change at the gas-liquid interface. Since the fluff is arranged in a vertical array, the gaps between them also form microscale vapor escape channels, further enhancing the evaporation flux. This process does not rely on an external heat source or forced convection and is entirely light-driven. Because the polymer fiber itself has corrosion resistance and mechanical stability, it can maintain high-efficiency evaporation performance for a long time in high-salt and acid-base alternating environments, solving the technical problem that conventional photothermal materials are prone to deactivation and difficult to reuse in seawater environments.

[0029] Further optimization of the design involves an array of hydrophilic yarns suspended and fixed to the fabric substrate. The suspension position of each hydrophilic yarn on the fabric substrate within the biomimetic root system 2 has a spatial synergy with the distribution of the fluff tissue in the corresponding photothermal layer 1: the suspension point of each hydrophilic yarn is located below the substrate gap between two adjacent fluff clumps, allowing seawater, after being transported upwards via the yarn, to preferentially diffuse laterally through this gap to the adjacent fluff roots, and then rise longitudinally along the fluff fibers to the surface evaporation zone. This synergy avoids uneven wetting and dry spot formation caused by water concentration in local fluff clumps, and also prevents the water supply path from being blocked by dense fluff, thus reducing water delivery efficiency. The suspension structure also allows the hydrophilic yarns to naturally droop and straighten after absorbing water, enhancing capillary driving force, while shrinking and rebounding in the dry state, maintaining the overall flexibility and foldability of the fabric.

[0030] In one embodiment of the present invention, since the biomimetic root system 2 is made of an array of hydrophilic yarns and is fixed to the fabric substrate in a suspended manner, a stable and expandable water intake channel can be constructed without damaging the integrity of the substrate. Since the suspended structure naturally forms an air gap between the photothermal layer 1 and the seawater 4, it provides a structural basis for heat localization. Since the array density and yarn material are adapted to the evaporation requirements of the photothermal layer 1, it supports the dynamic matching of water supply rate and evaporation rate. Since the fixing method relies entirely on the weaving process itself, it avoids the risk of interface failure and water flow obstruction caused by additional connections such as adhesives and sewing, and improves the long-term reliability and scalable manufacturing of the device.

[0031] Further optimization of the design involves using a hydrophilic yarn made from natural fibers rich in hydroxyl groups and possessing a microporous structure. The high hydroxyl content of the hydrophilic yarn enhances the hydrogen bonding between it and seawater molecules, thus improving initial wetting speed and interfacial stability. Furthermore, its nano- to micron-scale interconnected microporous structure generates considerable capillary pressure, providing a continuous and controllable mechanical driving force for the active upward transport of seawater. This synergistic effect enables the water supply layer to have dynamic response capabilities, automatically adjusting the water delivery intensity based on the instantaneous evaporation load of the photothermal layer. This supports a precise match between the water supply rate and the evaporation rate, ultimately ensuring the system's long-term stable operation under high-salt conditions, achieving 12 hours of salt-free crystallization and 1.5 hours of surface salt crystal self-dissolution.

[0032] In one embodiment of the present invention, the hydrophilic yarn is preferably ramie yarn, and the ramie yarn array is optimized based on Darcy's law, with the water delivery rate precisely matching the evaporation requirements.

[0033] In one embodiment of the present invention, the number (N) of the garlic root-shaped array of the water supply layer and the water supply rate (Q) are optimized based on Darcy's law. total） The following relationship must be satisfied: Where k is the inherent permeability of ramie yarn (m²), and A total The total effective water conveyance cross-sectional area (m²) is given by ΔP≈Pc (Pc is the capillary pressure generated by the micropores inside the ramie fiber, Pa), μ is the dynamic viscosity of seawater (Pa·s), and L is the length of the water conveyance path (m); the total effective water conveyance cross-sectional area A total =N×A single (Asingle is the average cross-sectional area of ​​a single ramie yarn, m²). Therefore, this microporous structure does not only serve a passive water storage function, but also acts as the core mechanical source for actively driving the directional transport of seawater from bottom to top, forming a dual-mechanism water absorption system of chemical affinity + physical drive in synergy with hydroxyl groups.

[0034] Further optimization of the scheme involves configuring the array quantity and distribution density of the biomimetic root system 2 to match the water supply rate of the water supply layer 5 with the evaporation rate of the photothermal layer 1. Because the array quantity and distribution density of the biomimetic root system 2 are configured to match the water supply rate with the evaporation rate, the water supply layer 5 can spontaneously establish a water transport rhythm consistent with the energy conversion rhythm of the photothermal layer 1 based on capillary action and Darcy flow laws without external driving force. This solves the problem of salt crystallization blockage and heat loss caused by the dynamic imbalance between water supply and evaporation, ensuring the stability and high efficiency of the device during long-term continuous operation.

[0035] Further optimization of the scheme involves creating a natural height difference between the photothermal layer 1 and the water supply layer 5, separating the evaporation interface of the device from the water to be treated. The low thermal conductivity of air forms a natural insulation structure, achieving a heat localization effect. The height difference between the water supply layer 5 and the photothermal layer 1 separates the evaporation interface from the water, utilizing the low thermal conductivity of air for natural insulation. The temperature of the photothermal surface can rapidly rise by more than 50°C, while the water temperature remains relatively unchanged, achieving excellent heat localization and preventing heat diffusion into the water.

[0036] In one embodiment of the present invention, after the device absorbs water, the biomimetic root system 2 included in the water supply layer 5 extends vertically in a suspended manner on the side of the fabric substrate away from the pile tissue, with its ends submerged in seawater 4. The top of the pile tissue of the photothermal layer 1 constitutes the actual evaporation interface, and there is a vertical gap filled with air between the top and the free liquid surface of the seawater 4. The height of this gap is determined by the hanging length of the biomimetic root system 2, and it does not rely on external supports or rigid partitions. It belongs to a stable geometric configuration formed by the gravity-capillary synergy of the woven structure itself. When sunlight irradiates the surface of the photothermal layer 1, the pile tissue absorbs light energy and converts it into heat energy, causing the liquid water at the interface to vaporize rapidly. Since there is an air insulation layer between the photothermal layer 1 and the seawater 4, the heat is difficult to dissipate downward to a large amount of water through heat conduction, resulting in a rapid increase in the surface temperature of the photothermal layer 1, while the temperature of the seawater 4 below remains basically unchanged. This temperature gradient strengthens the vapor pressure difference at the interface, further promoting the transition of water molecules from the liquid phase to the gas phase and increasing the evaporation flux per unit area.

[0037] The design was further optimized, and the molding process includes the following steps: The system provides warp and weft yarns, which are interwoven on a loom to form the fabric base. Ramie yarn is selected as the base material for the garlic root-like bionic root system. This material is not only inexpensive but also has excellent water absorption capacity, enabling rapid water transfer and meeting the evaporator's functional requirements for a water-absorbing base material. PET fiber is selected as the base material for the top photothermal layer. PET fiber has a light absorption rate of ≥95%, which can efficiently absorb sunlight and convert it into heat energy. PET fiber is also inexpensive, water-resistant, and suitable for the long-term use of the evaporator. It also has good compatibility with the ramie yarn base material, facilitating subsequent structural assembly. Ramie yarn is used as the warp yarn, and warping and tension control are achieved through the loom's heald frame and stop-warp system to form a uniformly distributed warp layer. PET (polyethylene terephthalate) fiber is used as the weft yarn, which is interwoven with the warp yarn under the action of the loom's weft insertion mechanism to form the fabric base. The weft yarns between adjacent warp yarns are lifted to the fabric surface using a pile-raising method to form a pile structure for the photothermal layer 1. Then, weft yarns are introduced to fix the pile structure. During the weft yarn interlacing process, PET is vertically drawn out from the fabric substrate surface in the form of loops or pile through a pile-raising operation. These protruding piles constitute the photothermal layer 1 of the evaporator. After each weft yarn is inserted, ramie yarn is suspended below the warp yarn to form a garlic root-like biomimetic root system 2, which is then fixed by the weft yarn. After the PET napping operation, a weft beat-up is performed to make the nap compact. Then, ramie yarn segments are suspended sequentially on the weft yarn to form a stable suspension structure, ensuring that the nap does not fall off during subsequent hot pressing and evaporation. At the same time, the natural porosity and capillary action of the ramie yarn segments are utilized to achieve efficient and continuous water transport from the substrate to the photothermal layer. After weaving, the fabric is set and finished to stabilize its structure and properties. The final integrated fabric consists of an upper PET photothermal layer 1 and a lower water supply layer 5 with ramie biomimetic root system 2. The two layers are interwoven to form an inseparable whole structure. Repeat the above steps to complete the weaving of the entire device.

[0038] In one embodiment of the present invention, the material selection should focus on three key factors: the controllability of material cost, the water absorption capacity of water-absorbing materials, and the light absorption rate of photothermal materials, so as to ensure that the selected materials not only meet the low cost requirements, but also match the core functional positioning of the evaporator in water absorption and photothermal conversion.

[0039] In one embodiment of the present invention, the steps for determining the key optimization parameters affecting the evaporator evaporation efficiency and clarifying the candidate ranges for each parameter are as follows: The number of ramie threads for the garlic root-shaped biomimetic root system 2 is as follows: Considering the water absorption capacity of the ramie threads, material costs, and the overall size of the evaporator, the alternative values ​​for the number of ramie threads are determined to be 100, 200, and 300 threads; among them, 100 threads is the lower limit of low cost to meet basic water absorption needs, and 300 threads is the upper limit of water absorption capacity to avoid material waste that would lead to increased costs.

[0040] Alternative heights for the PET fibers in the top photothermal layer 1: Considering the photothermal conversion efficiency of the PET fibers, the heat conduction effect, and the rationality of the evaporator structure, alternative heights for the PET fibers are determined to be 1mm, 5mm, and 10mm; where 1mm is the lower limit of the photothermal layer thickness to meet the basic photothermal absorption requirements, and 10mm is the upper limit of the thickness to avoid excessive thickness leading to heat loss.

[0041] In one embodiment of the present invention, a determined number of ramie threads and the height of PET fibers are combined to design multiple sets of control experiments. By testing the evaporation rate of each group of evaporators, the parameter combination with the highest evaporation rate is selected. Variables are strictly controlled during the experiment to ensure the accuracy of the results. The experimental data are closely related to the core objective of improving evaporation efficiency in the invention. The specific implementation process is as follows: Combination scheme design: Three alternative values ​​for the number of ramie threads (100, 200, 300) and three alternative values ​​for the height of PET fibers (1mm, 5mm, 10mm) were combined to obtain a total of 9 experimental combinations, as follows: Option 1: 100 strands of ramie thread + 1mm of PET fiber; Option 2: 100 strands of ramie thread + 5mm of PET fiber; Option 3: 100 strands of ramie thread + 10mm of PET fiber; Option 4: 200 strands of ramie thread + 1mm of PET fiber; Option 5: 200 strands of ramie thread + 5mm of PET fiber; Option 6: 200 strands of ramie thread + 10mm of PET fiber; Option 7: 300 strands of ramie thread + 1mm of PET fiber; Option 8: 300 strands of ramie thread + 5mm of PET fiber; Option 9: 300 ramie threads + 10mm PET fiber.

[0042] Evaporation experiments were conducted as follows: Nine integrated fabric-based solar interface evaporator samples were prepared according to the nine combination schemes described above. The preparation process and material specifications (except for the number of ramie threads and the height of PET fibers) of each sample were kept completely consistent, ensuring that the experimental variables were unique. All nine samples were simultaneously tested in the same experimental environment, with strictly controlled environmental parameters: room temperature 25℃, standard atmospheric pressure, and solar irradiance of 1000 W / m². The initial mass of water for each sample was set to 500 g, and the experiment lasted for 8 hours. During the experiment, the remaining mass of water for each sample was recorded every hour, and the real-time evaporation rate was calculated based on the recorded data.

[0043] Evaporation rate calculation method: In the formula, Δm is the mass loss during the evaporation process, A is the effective evaporation area (m²), and t is the evaporation time (h).

[0044] Evaporation efficiency calculation method: In the formula, h LV q is the enthalpy of evaporation of water. in This represents the incident light flux.

[0045] Half an hour after the xenon lamp is turned on, uniform sunlight power is projected onto the upper surface of the evaporator. The mass change of the evaporation system is recorded every 10 seconds using an electronic balance, and the evaporation rate and efficiency are calculated accordingly.

[0046] Determination of optimal parameters: Through statistical analysis and calculation of experimental data, evaporation rate data of 9 schemes were obtained. Comparative analysis revealed that Scheme 6 (200 ramie threads + 10mm PET fiber height) had the highest evaporation rate, with an average evaporation rate of 1.66kg / (m²·h) over 8 hours, which was significantly higher than the other 8 schemes. Analysis of the reasons: The water absorption capacity of 200 ramie threads is moderate, which can quickly transfer water without the material stacking due to excessive quantity affecting heat conduction; the 10mm high PET fiber photothermal layer can fully absorb sunlight and has a moderate thickness, reducing the loss of heat energy to the deeper layers of water. The two work together to achieve the highest evaporation efficiency. Therefore, the specific implementation parameters of this invention are determined as follows: 200 ramie threads in the garlic root biomimetic root system, and 10mm high PET fiber photothermal layer at the top.

[0047] Additional notes: The ramie thread used in this embodiment has a diameter of 0.6 mm, and the PET fiber has a diameter of 0.2 mm. This embodiment is a structural component assembly, focusing on structural parameters. All materials meet the requirements of low cost and easy availability. The preparation process is simple and can be mass-produced, fully conforming to the inventive concept and core requirements of this invention.

[0048] Further optimization of the scheme: the hydrophilic yarn is combined with the fabric substrate through a weaving fixed structure to achieve the synchronous forming of the photothermal layer 1 pile and the water supply layer 5 array.

[0049] In one embodiment of the invention, the system adopts an all-fabric structure, requiring no chemical modification, conforming to the concept of green manufacturing, and possessing excellent corrosion resistance (resistant to acid, alkali, and high-salt environments), mechanical strength, and washability. After 8 cycles (8 hours per cycle), its evaporation performance shows no decline, and it exhibits no salt crystallization after 12 hours of continuous operation. Furthermore, surface salt crystals can self-dissolve within 1.5 hours, demonstrating long-term stable operation. In outdoor applications, it can stably produce fresh water. After desalination, the concentration of ions (Na⁺, Mg²⁺, K⁺, Ca²⁺) in the water is significantly reduced, meeting WHO drinking water standards. It can be used in agricultural irrigation and other scenarios, with a wide range of applications.

[0050] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0051] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A solar-driven seawater interface evaporation device based on garlic root biomimetic fabric, characterized in that: It includes a photothermal layer (1) and a water supply layer (5), wherein the photothermal layer (1) and the water supply layer (5) are integrally woven and have self-supporting properties after absorbing water; The photothermal layer (1) includes a fabric substrate, the surface of which a pile structure is vertically drawn out through a pile raising operation; The water supply layer (5) includes a biomimetic root system (2) immersed in seawater (4). The biomimetic root system (2) is configured as a garlic root-shaped biomimetic tissue. The biomimetic root system (2) is suspended on the side of the fabric substrate away from the fluff tissue. The biomimetic root system (2) is arranged in an array. The biomimetic root system (2) transmits seawater (4) to the photothermal layer (1).

2. The solar-driven seawater interface evaporation device based on garlic root biomimetic fabric according to claim 1, characterized in that: The photothermal layer (1) and the water supply layer (5) are integrally formed by weft-laid wool weaving process.

3. The solar-driven seawater interface evaporation device based on garlic root biomimetic fabric according to claim 1, characterized in that: The villous tissue is composed of polymer fibers.

4. The solar-driven seawater interface evaporation device based on garlic root biomimetic fabric according to claim 3, characterized in that: The polymer fiber is polyethylene terephthalate fiber.

5. The solar-driven seawater interface evaporation device based on garlic root biomimetic fabric according to claim 1, characterized in that: The biomimetic root system (2) includes an array of hydrophilic yarns, which are suspended and fixed on the fabric substrate.

6. The solar-driven seawater interface evaporation device based on garlic root biomimetic fabric according to claim 5, characterized in that: The hydrophilic yarn is a natural fiber yarn rich in hydroxyl groups and with a microporous structure inside.

7. The solar-driven seawater interface evaporation device based on garlic root biomimetic fabric according to claim 1, characterized in that: The array number and distribution density of the biomimetic root system (2) are configured in a way that the water supply rate of the water supply layer (5) matches the evaporation rate of the photothermal layer (1).

8. The solar-driven seawater interface evaporation device based on garlic root biomimetic fabric according to claim 1, characterized in that: A natural height difference is formed between the photothermal layer (1) and the water supply layer (5), which separates the evaporation interface of the device from the water to be treated. The low thermal conductivity of air forms a natural heat insulation structure, thereby achieving the effect of heat localization.

9. The solar-driven seawater interface evaporation device based on garlic root biomimetic fabric according to claim 5, characterized in that, The molding process includes the following steps: Provide warp and weft yarns, and interweave the warp and weft yarns on a loom to form the fabric base; The pile structure is formed by lifting the weft yarn between adjacent warp yarns to the fabric surface to form a photothermal layer (1) through the pile raising method, and then the weft yarn is introduced to fix the pile structure; After each weft yarn is inserted, ramie yarn is suspended below the warp yarn to form a garlic root-like bionic root system (2), and then the bionic root system (2) is fixed by the weft yarn; After weaving, the fabric is set and finished to stabilize its structure and properties; Repeat the above steps to complete the weaving of the entire device.

10. The solar-driven seawater interface evaporation device based on garlic root biomimetic fabric according to claim 9, characterized in that: The hydrophilic yarn is combined with the fabric substrate through a weaving fixed structure to achieve synchronous forming of the fluff of the photothermal layer (1) and the array of the water supply layer (5).

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