A solid-liquid friction nanogenerator method and device based on flow state regulation

Abstract

The present application relates to the technical field of new energy, in particular to a kind of solid-liquid friction nano power generation method and device based on flow state regulation.The device includes a liquid storage container, a siphon is arranged in the liquid storage container, one end of the siphon is placed inside the liquid storage container, the other end is communicated with a friction power generation tube, an outer electrode is wound on the outer side wall of the friction power generation tube, an inner electrode is inserted into the lower end of the inner side of the friction power generation tube, and the inner electrode and the outer electrode are connected with an external circuit.The method includes forming a continuous liquid column flow, a transition flow state in which liquid drop flow and liquid column flow appear alternately, or a liquid drop flow state of discrete liquid drop flow in the friction power generation tube by controlling the liquid supply conditions.The present application utilizes the siphon effect, adjusts the injection flow of the liquid in the liquid storage container, thereby actively controls the system to be in the liquid drop flow (charge accumulation mode) or liquid column flow (charge release mode) state, and realizes the precise regulation of the charge accumulation and release process.

Description

Technical Field

[0001] This invention relates to the field of new energy technology, and in particular to a solid-liquid triboelectric nanogenerator method and device based on flow state control. Background Technology

[0002] With the development of new energy technologies, triboelectric nanogenerators (TENGs), as a technology that can convert low-frequency mechanical energy in the environment into electrical energy, have received widespread attention in recent years. Among them, solid-liquid triboelectric nanogenerators (SL-TENGs) have shown good application prospects in the fields of blue energy harvesting and self-powered sensing because they can directly utilize the mechanical energy in natural water resources such as rainwater, water flow, and ocean waves.

[0003] Existing triboelectric nanogenerators typically rely on triboelectric charging and electrostatic induction effects between liquids and solid dielectric materials. However, in most existing technologies, the liquid maintains an electrical connection with the electrode throughout its flow, causing the charge generated at the interface to be gradually released through the liquid after formation. This results in a high degree of coupling between the charge accumulation and release processes, making it difficult to achieve effective charge storage.

[0004] Due to this coupling relationship between charge generation and release, existing SL-TENG devices typically have the following shortcomings:

[0005] 1. The charge accumulation and release processes are highly coupled, making it difficult to store charge effectively. In traditional solid-liquid triboelectric nanogenerators, the generation and release of charge at the solid-liquid interface are inseparable in time. When a liquid comes into contact with a solid medium, triboelectric charges are generated at the interface, and once a continuous conductive path is formed, the charges are immediately dissipated. This synchronicity of charge accumulation and release means that the charge cannot be effectively stored within the device, severely limiting the output energy density.

[0006] 2. Lack of an effective charge release control mechanism limits output power. Because it is impossible to decouple the time sequence of charge accumulation and release, existing technologies struggle to actively control the charge release process. Charge at the interface exhibits a "simultaneous generation and dissipation" state, making concentrated charge output impossible. Therefore, the output power of existing solid-liquid triboelectric nanogenerators is generally limited to the milliwatt level, making it difficult to directly drive commercial high-power electronic devices.

[0007] 3. Relying on external drives and lacking flow regulation methods, the system lacks autonomy and controllability. While existing tubular triboelectric nanogenerators can achieve droplet or column flow, they often rely on energy-intensive components such as external pumps and compressors to regulate the fluid state. This not only increases the system's size, cost, and maintenance complexity but also diminishes the autonomous advantage of harvesting energy from natural water sources (such as rainwater). Furthermore, the lack of methods to actively regulate the timing of charge accumulation and release using flow state changes, coupled with the lack of effective control over charge behavior at the interface, makes the device performance highly sensitive to the liquid flow state and difficult to optimize.

[0008] To improve output performance, existing research mainly focuses on increasing the amount of charge generated by increasing the solid-liquid contact area, optimizing material properties, or increasing the liquid flow rate. However, these methods primarily concentrate on improving the charge generation process, failing to effectively control the charge accumulation and release process from a charge management perspective. Therefore, how to achieve controllable accumulation and on-demand release of interface charge through structural design, thereby improving the efficiency of triboelectric charge utilization, remains a pressing technical problem to be solved in this field.

[0009] Furthermore, existing technologies rarely involve technical solutions for managing interface charge by altering the electrical continuity of the liquid through regulating the liquid flow pattern. In particular, there is a lack of power generation structures that achieve charge accumulation and collective release by switching between electrically isolated and electrically connected states through the conversion between droplet flow and liquid column flow. Summary of the Invention

[0010] In order to decouple the charge accumulation and release processes without external drive (without external devices such as peristaltic pumps, air pumps, etc.) and to achieve charge management through liquid flow regulation, this invention provides a solid-liquid triboelectric nano-power generation method and device based on flow regulation.

[0011] Therefore, the present invention provides the following technical solution: A flow-controlled solid-liquid triboelectric nano-power generation method is disclosed, which employs a flow-controlled solid-liquid triboelectric nano-power generation device. The power generation device includes a liquid storage container with an inverted U-shaped siphon tube on it. One end of the siphon tube is connected to the inside of the liquid storage container, and the other end is connected to a triboelectric power generation tube. An external electrode is wound around the outer wall of the triboelectric power generation tube, and an internal electrode is inserted into the inner side of the lower end of the triboelectric power generation tube. Both the internal and external electrodes are connected to an external circuit. The method includes: The liquid storage container is drained into the friction generator tube through a siphon tube; By controlling the liquid supply conditions, a liquid column flow state with continuous liquid column flow, a transitional flow state with alternating liquid droplet flow and liquid column flow, or a droplet flow state with discrete liquid droplet flow can be formed in the triboelectric generator tube. Select a triboelectric tube with the appropriate length and cross-sectional dimensions to obtain the required power output.

[0012] Furthermore, in the liquid column flow state, the liquid injection flow rate is less than the steady-state discharge flow rate of the siphon tube, and the siphon process can be periodically and naturally interrupted; in this flow state, the liquid passes through the friction generator tube in the form of a continuous and complete liquid column. Under the transitional flow state, the liquid injection flow rate is between that of the liquid column flow state and the liquid droplet flow state, and the siphon process can still be interrupted intermittently; under this flow state, the liquid in the triboelectric generator tube exhibits an unsteady flow pattern in which liquid column flow and liquid droplet flow alternate. In the droplet flow state, the liquid injection flow rate is greater than the steady-state discharge flow rate of the siphon tube, and the siphon process runs continuously without interruption; in this flow state, the liquid passes through the triboelectric generator tube in the form of discrete droplets. The liquid injection flow rate is adjusted according to the length of the triboelectric tube to achieve the above-mentioned flow state conversion; wherein, the longer the triboelectric tube, the smaller the injection flow rate required to achieve the flow state conversion.

[0013] Furthermore, the volume corresponding to the outer electrode winding area on the triboelectric generator tube is matched with the volume of liquid discharged by the siphon tube in a single flow state under liquid column flow conditions; The length of the triboelectric tube should be selected based on the required output voltage. The higher the required output voltage, the longer the triboelectric tube should be.

[0014] A flow-controlled solid-liquid triboelectric nanogenerator is provided for realizing the flow-controlled solid-liquid triboelectric nanogenerator method. The device includes a support and a liquid storage container, wherein the liquid storage container is fixedly installed on the support.

[0015] Furthermore, a collection funnel is also fixedly installed on the support, the collection funnel is located above the liquid storage container, and the inlet of the liquid storage container is located directly below the outlet of the collection funnel.

[0016] Furthermore, a filter funnel is also fixedly installed on the support, and the filter funnel is located above the collection funnel.

[0017] Furthermore, the outlet of the collection funnel is connected to the inlet of the liquid storage container via a pipeline, and a regulating valve is installed on the pipeline.

[0018] Furthermore, the liquid storage container and the siphon tube are integrally molded from a transparent material.

[0019] Furthermore, the triboelectric tube is a fluorinated ethylene propylene copolymer tube or a polytetrafluoroethylene tube, the outer electrode is a conductive copper foil, and the inner electrode is a metal wire.

[0020] Furthermore, the liquid storage containers are arranged in an array, and each liquid storage container is provided with a corresponding siphon tube; the outer electrodes of the triboelectric tubes connected to each siphon tube are connected in parallel, and the inner electrodes are connected in parallel.

[0021] Advantages and positive effects of the present invention: This invention involves injecting liquid into a storage container and then using a siphon tube to introduce the liquid from the storage container into a triboelectric generator tube under siphoning. By changing the flow rate of the injected liquid, the fluid state in the triboelectric generator tube is changed, forming liquid column flow, transition flow, and droplet flow.

[0022] In the droplet flow state, the air gaps between the droplets create electrical isolation, allowing triboelectric charges to gradually accumulate on the inner wall of the triboelectric generator without being immediately dissipated. In the liquid column flow state, the liquid restores electrical continuity, triggering a collective release of charges. In the transitional flow state, droplet flow and liquid column flow alternate, with droplet flow accumulating charges and liquid column flow releasing charges. This "accumulation first, release later" working mode achieves high-density storage and concentrated release of charges.

[0023] By achieving effective accumulation and concentrated release of charge, this invention can output a peak open-circuit voltage of over 4000V, a peak short-circuit current of over 6mA, and a peak power of over 5W without any external driving components. It is the first to achieve watt-level output of a solid-liquid triboelectric nanogenerator, which can directly drive commercial high-power lighting and other electronic devices.

[0024] This invention utilizes the siphon effect to achieve autonomous, intermittent liquid transport, eliminating the need for external energy-intensive components such as pumps and compressors. The system is simple in structure, low in cost, and easy to maintain. Furthermore, since it does not consume external energy, it can fully utilize natural water sources (such as rainwater and river water) for energy harvesting, truly achieving autonomous and green energy supply.

[0025] This invention adjusts the liquid supply frequency, thereby regulating the injection flow rate of the liquid in the storage container. This allows the system to be actively controlled in either droplet flow (charge accumulation mode) or column flow (charge release mode), achieving precise control over the charge accumulation and release process.

[0026] The power generation units of this invention can be easily connected in parallel to form an array structure, flexibly expanding the output power according to application requirements. Simultaneously, the same structure can operate in a transitional flow state to achieve high power output, or in a liquid column flow state to achieve quantitative electrical pulse output, combining the dual functions of high-power power generation and self-powered sensing. It can be widely applied in fields such as blue energy harvesting, marine monitoring, smart agriculture, and urban rainwater management. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A schematic diagram of a solid-liquid triboelectric nanogenerator based on flow regime control is provided for this invention.

[0029] Figure 2 The present invention provides a solid-liquid triboelectric nanogenerator based on flow regime control, showing the working principle of a complete siphon cycle under liquid column flow.

[0030] Figure 3 The figure shows the test results of the output performance of a solid-liquid triboelectric nanogenerator based on flow regime control under the condition of no external drive.

[0031] Figure 4 The figure shows the parameter optimization test results of a solid-liquid triboelectric nanogenerator based on flow regime control provided by the present invention.

[0032] Figure 5 The present invention provides flow diagrams of liquid column, transition flow, and droplet flow of a solid-liquid triboelectric nanogenerator based on flow regime control.

[0033] Figure 6 This is a distribution diagram of droplet frequency and FEP tube length corresponding to different flow regimes.

[0034] Figure 7 The graph shows the voltage output test results for different flow states.

[0035] Figure 8 The graph shows the variation of peak open-circuit voltage with droplet frequency for different FEP tube lengths under different flow conditions.

[0036] Figure 9 The graph shows the peak short-circuit current and transferred charge of a 20 cm FEP tube as a function of droplet frequency.

[0037] Figure 10 This is a line graph showing the change in output power as a function of the external load resistance.

[0038] Figure 11 This is a schematic diagram of the charge accumulation and discharge process.

[0039] Figure 12 This is a local equivalent circuit diagram formed when a single droplet contacts the internal electrode.

[0040] Figure 13This is the global equivalent circuit diagram formed when the liquid column contacts the internal electrode.

[0041] Figure 14 This is a diagram showing the evolution of the surface potential of the inner wall of the FEP during the droplet-liquid column transition.

[0042] Figure 15 This is a diagram showing the charging characteristics of a capacitor under different flow conditions.

[0043] Figure 16 This is a physical diagram of an array parallel structure of a solid-liquid triboelectric nanogenerator based on flow regime control, provided by the present invention.

[0044] Figure 17 The output voltage diagram is shown for the parallel array structure under transient current conditions.

[0045] Figure 18 A physical diagram of a parallel array structure with a light bulb lit.

[0046] Figure 19 The present invention provides a solid-liquid triboelectric nanogenerator based on flow regime control, which, when functioning as a rain gauge, generates water discharge during ten consecutive siphon events.

[0047] Figure 20 The voltage output diagram is used to simulate different rainfall intensities.

[0048] Figure 21 This is a comparison chart of actual measured rainfall and reference values.

[0049] In the diagram: 1. Liquid storage container; 2. Siphon tube; 3. Triboelectric generator tube; 4. External electrode; 5. Internal electrode; 6. Support; 7. Collection funnel; 8. Filter funnel; 9. Regulating valve. Detailed Implementation

[0050] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. 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 should fall within the scope of protection of the present invention.

[0051] This invention provides a solid-liquid triboelectric nano-power generation method based on flow state control, and a solid-liquid triboelectric nano-power generation device based on flow state control.

[0052] Power generation devices such as Figure 1As shown, it includes a support 6 and a liquid storage container 1. The liquid storage container 1 is fixedly installed on the support 6. An inverted U-shaped siphon tube 2 is provided on the liquid storage container 1. One end of the siphon tube 2 is connected to the inside of the liquid storage container 1, and the other end is connected to a triboelectric tube 3. An external electrode 4 is wound around the outer wall of the triboelectric tube 3. An internal electrode 5 is inserted into the inner side of the lower end of the triboelectric tube 3. The internal electrode 5 and the external electrode 4 form an electrode pair. Both the internal electrode 5 and the external electrode 4 are connected to an external circuit.

[0053] The liquid storage container 1 and the siphon tube 2 are integrally molded using 3D printing technology, and the material is selected from transparent photosensitive resin. The aim is to ensure that there are no assembly gaps or leaks between the liquid storage container and the siphon tube, resulting in a strong overall structure; at the same time, it facilitates real-time observation of the liquid flow state and flow pattern changes within the liquid storage container and the siphon tube, thereby improving the accuracy of experimental observation and control.

[0054] The triboelectric generator tube 3 is a fluorinated ethylene-propylene copolymer tube or a polytetrafluoroethylene tube, with an inner diameter of 3-5 mm and a length of 6-20 cm. The outer electrode 4 is a conductive copper foil with a thickness of 50-100 μm. The inner electrode 5 is a metal wire with a diameter of 0.2-0.5 mm.

[0055] A collecting funnel 7 is also fixedly installed on the bracket 6. The collecting funnel 7 is located above the liquid storage container 1, and the inlet of the liquid storage container 1 is connected to the outlet of the collecting funnel 7 through a pipeline. A regulating valve 9 is installed on the pipeline between the collecting funnel 7 and the liquid storage container 1, which can be used to adjust the liquid injection frequency.

[0056] A filter funnel 8 is also fixedly installed on the bracket 6, and the filter funnel 8 is located above the collection funnel 7.

[0057] The methods include: Liquid is pumped into the storage container 1 by a peristaltic pump or external rainwater. The liquid first passes through the filter funnel 8 to remove impurities and then flows into the collection funnel 7, which expands the liquid collection area of ​​the storage container 1.

[0058] When the liquid level in the storage container 1 rises above the top of the inverted U-shaped siphon tube 2, the siphon effect causes the storage container 1 to discharge liquid into the friction generator tube 3 through the siphon tube 2 until the liquid level in the storage container 1 drops below the inlet end of the siphon tube 2, thus completing one transport cycle.

[0059] By controlling the liquid supply conditions, a liquid column flow state with continuous liquid column flow, a transitional flow state with alternating liquid droplet flow and liquid column flow, or a droplet flow state with discrete liquid droplet flow can be formed in the triboelectric tube 3.

[0060] Under liquid column flow conditions, the liquid injection flow rate is less than the steady-state discharge flow rate of the siphon tube, and the siphon process can be interrupted periodically and naturally. Under these conditions, the liquid passes through the triboelectric generator tube in the form of a continuous and complete liquid column. The electrical output signal is most stable under these conditions.

[0061] Under the transitional flow state, the liquid injection flow rate is between that of the liquid column flow state and the liquid droplet flow state, and the siphon process can still be interrupted intermittently; under this flow state, the liquid in the triboelectric tube 3 exhibits an unsteady flow pattern in which liquid column flow and liquid droplet flow alternate; the electrical output intensity is strongest under this state.

[0062] In the droplet flow state, the liquid injection flow rate is greater than the steady-state discharge flow rate of the siphon tube 2, and the siphon process continues to run without interruption; in this flow state, the liquid passes through the triboelectric generator tube 3 in the form of discrete droplets; in this state, the generator tube can continuously accumulate charge.

[0063] Adjust the liquid injection flow rate according to the length of the triboelectric tube 3 to achieve the above-mentioned flow state conversion; take the triboelectric tube 3 with the corresponding length and cross-sectional size to obtain the required power output.

[0064] The volume corresponding to the area where the outer electrode 4 is wound on the triboelectric tube 3 is matched with the volume of liquid discharged by the siphon tube 2 in a single flow state under liquid column conditions; the length of the triboelectric tube 3 is selected according to the required output voltage, and the higher the required output voltage, the longer the selected length of the triboelectric tube 3.

[0065] Example 1 The triboelectric generator tube is made of fluorinated ethylene propylene copolymer (FEP) and is 10 cm long with an inner diameter of 4 mm and an outer diameter of 6 mm. The outer electrode is made of 75 μm thick conductive copper foil tightly wound around the outer wall of the FEP tube. The inner electrode is a 0.4 mm diameter copper wire inserted radially into the FEP tube, located on the side of the FEP tube's outlet. Both the inner and outer electrodes are connected to an external circuit for outputting electrical signals.

[0066] The FEP tube was ultrasonically cleaned for 10 minutes each in ethanol and deionized water to remove surface contaminants. After drying, the inner electrode was inserted into the FEP tube and fixed in place, the outer electrode was wrapped around the outer wall of the FEP tube, and the inlet of the FEP tube was sealed to the outlet of the siphon tube.

[0067] like Figure 2 As shown, liquid is continuously supplied to the storage container (the frequency of the supplied droplets is 4Hz), resulting in a liquid column flow at this frequency. The liquid level in the storage container gradually rises (Ⅰ). When the liquid level exceeds the top of the siphon tube, the siphon effect is activated (Ⅱ), and the liquid is autonomously transported through the siphon tube to the triboelectric generator tube (Ⅲ). When the liquid contacts the internal electrode in the FEP tube (Ⅳ), a significant electrical output is generated. The volume of a single delivery is determined by the geometric parameters of the siphon tube; in this embodiment, it is 1.28 mL. After delivery, the liquid level drops below the inlet end of the siphon tube (Ⅰ), the siphon is interrupted, and a complete siphon-electricity generation cycle is completed. Continuous droplet supply will repeat this process, forming a self-regulating cycle of fluid-driven charge generation.

[0068] The output performance test results of the power generation device under conditions without external drive are as follows: like Figure 3 As shown in (a), the open-circuit voltage was measured using a 100MΩ high-voltage probe and an oscilloscope, and was 1200V. Figure 3 As shown in (b), the short-circuit current was measured to be 850 μA using a low-noise current preamplifier and oscilloscope. Figure 3 As shown in (c), the charge transferred in a single discharge is 41.5 nC, as measured by an electrometer.

[0069] Optimization parameter tests were conducted under liquid column flow conditions. like Figure 4 As shown in (a), the parameters involved in the study include the inner diameter of the FEP pipe ( D ), tilt angle ( θ ), FEP tube length ( L ) and liquid column volume (i.e., siphon drainage volume) V ).

[0070] like Figure 4 As shown in (b), inner diameter D Impact on output voltage (outer diameter fixed at 6mm). The tube with a 3mm inner diameter produces a slightly higher voltage than the tube with a 4mm inner diameter, while the output voltage of the tube with a 5mm inner diameter decreases. Considering overall performance and structural stability, the tube selected... D =4mm ( L =10cm; θ =90°; V =1.28mL).

[0071] like Figure 4 As shown in (c), the tilt angle θ The output voltage increases with increasing angle, reaching its peak at 90°. L =10cm; D =4mm; V =1.28mL).

[0072] like Figure 4 As shown in (d), the length L The output voltage increases with increasing tube length. D =4mm; θ =90°; V =1.28mL).

[0073] like Figure 4 As shown in (e), the volume V The output voltage increases with increasing volume, and... VIt tends to saturate when it approaches the internal volume of the tube. L =15cm; D =4mm; θ =90°).

[0074] like Figure 4 As shown in (f), the effect of liquid type on output voltage is mainly controlled by the difference in liquid ion concentration and conductivity. The optimized configuration uses an FEP tube with an inner diameter of 4mm and a tilt angle of... θ =90°, liquid volume is adjusted according to pipe length, tap water is used unless otherwise specified.

[0075] Example 2 The experiment used a siphon tube with a single delivery volume of 2.55 mL. The FEP tube was 15 cm long, with an inner diameter of 4 mm and an outer diameter of 6 mm. A peristaltic pump was used to precisely control the frequency of the input droplets into the storage container, thereby controlling the injection flow rate. The droplet volume was fixed at 100 μL. A DSLR camera was used to record the flow state inside the FEP tube. The liquid supply frequency was controlled within the range of 1-20 Hz by adjusting the speed of the peristaltic pump. Based on the observation results, the flow state inside the FEP tube was divided into three flow regimes, such as... Figure 5 As shown in (a), when the supply frequency is ≤5Hz, the single delivery volume of the siphon tube is 2.55mL, and the liquid is delivered in the FEP tube in the form of a continuous liquid column, which is a liquid column flow state; Figure 5 As shown in (b), when the supply frequency is 6-12Hz, droplet flow and liquid column flow alternate, which is a transitional flow state; Figure 5 As shown in Figure c, when the supply frequency is ≥13Hz, the liquid is transported in the FEP tube in the form of discrete droplets, which is a droplet flow state.

[0076] Tests were conducted using FEP tubes of different lengths (10cm, 12.5cm, 15cm, 17.5cm, 20cm), such as... Figure 6 As shown, Figure 6 The image shows three different colored regions, from left to right: liquid column flow, transitional flow, and droplet flow. The results indicate that the longer the FEP tube, the lower the critical supply frequency required to form droplet flow. For example, for a 20cm long FEP tube, the critical frequency is approximately 9Hz; for a 10cm long FEP tube, the critical frequency is approximately 19Hz. This phenomenon allows for flexible design of device operating states based on application scenarios.

[0077] In the liquid column flow state, such as Figure 7 As shown in (a), the volume of liquid discharged from the siphon tube remains almost constant during each siphon process, thus generating a relatively stable voltage output. However, in the droplet flow state, as... Figure 7As shown in (b), despite the high electrical triggering frequency, the voltage remains at a low level. In contrast, alternating droplet and column flows occur in the transitional flow state, with charge accumulation during droplet formation and transient ultra-high voltage pulses generated when the column forms, such as... Figure 7 As shown in (c).

[0078] like Figure 8 As shown, a high-voltage probe and oscilloscope were used to measure the peak open-circuit voltage under different flow conditions. The results show that: Under liquid column flow conditions, the output voltage remains stable above 1000V.

[0079] Under transient current conditions, the output voltage increases significantly with increasing frequency, reaching a maximum of 4250V at 8Hz (FEP tube length 20cm); In droplet flow mode, the output voltage drops below 1000V.

[0080] like Figure 9 As shown, under optimal conditions (FEP tube length 20cm, supply frequency 8Hz), the measured peak short-circuit current is 6.8mA, and the maximum single-transfer charge is 450nC.

[0081] like Figure 10 As shown, the output power was measured under different load resistances. The results show that when the load resistance is 900kΩ, the maximum output power reaches 5W, and the corresponding power density is approximately 2MW / m². 3 .

[0082] In droplet flow, such as Figure 11 As shown in (I), discrete droplets repeatedly come into contact with and separate from the inner surface of the FEP tube, causing a gradual accumulation of negative charge on the FEP surface. Because the droplets are separated by air gaps, each droplet / FEP interface is equivalent to an electrically isolated interface. C One unit (the water / FEP interface forms an electric double layer (EDL), which can be regarded as a capacitor) C 1). This isolation prevents electrical continuity along the pipe direction, suppresses continuous charge dissipation, and thus enables efficient charge storage on the FEP surface.

[0083] When a single droplet contacts the internal electrode, such as Figure 11 As shown in (II), a local equivalent circuit will be formed, such as Figure 12 As shown. Among them R L , R W These represent the load resistance and the liquid resistance, respectively; the water / internal electrode interface forms an EDL, which can be considered as a capacitor. C 2, and a capacitor consisting of an FEP and an external electrode. C F Connected. Therefore, only locally accumulated charge (Q local The voltage is released, resulting in a relatively low voltage.

[0084] When a liquid column forms, such as Figure 11 As shown in (III), the air gap disappears, and the originally isolated C Electrical continuity was restored between units 1. For example... Figure 11 As shown in (IV), when the liquid column contacts the internal electrode, a global equivalent circuit is established (e.g., Figure 13 As shown), triggering the collective release of stored charge ( Q global Q local This results in the observed voltage amplification effect. This shift from spatially isolated release to collective release is the physical root of the abnormal voltage pulse in the transition flow state.

[0085] To reveal the mechanism by which flow regime control affects charge behavior, the following verification experiments were conducted in this embodiment: Surface potential measurement: The surface potential of the inner wall of the FEP tube was measured using a non-contact electrostatic field meter (SIMCOFMX-003). The inner wall of the FEP tube was first treated with an ionizer to eliminate residual charge. For example... Figure 14 As shown, in the droplet flow state, the surface potential of the inner wall of the FEP tube gradually increases, indicating that the charge continues to accumulate; when the flow state switches to liquid column flow, the surface potential drops sharply, indicating that the charge is released collectively.

[0086] Capacitor charging test: such as Figure 15 As shown, a 4.7 μF capacitor was used as a load and connected to the output terminal of the solid-liquid triboelectric nanogenerator. Charging curves under different flow conditions were measured. The results show that: Liquid column flow state: The capacitor voltage rises in a step-like manner, and each liquid column flow event produces a significant voltage jump.

[0087] Droplet flow state: The capacitor voltage rises smoothly, the electrical output frequency is high, but the charging amount per event is small.

[0088] Transitional flow state: The capacitor charges the fastest and eventually has the highest voltage.

[0089] Example 3 To meet different power requirements, the liquid storage containers 1 are arranged in an array, and each liquid storage container 1 is equipped with a corresponding siphon tube 2; the outer electrodes 4 of the triboelectric generator tubes 3 connected to each siphon tube 2 are connected in parallel, and the inner electrodes 5 are connected in parallel. Multiple sets of siphon tubes 2 and triboelectric generator tubes 3 are connected in parallel to expand the output power. Figure 16As shown, this embodiment constructs a high-output array solid-liquid power generation device (High-output SSL-TENG) consisting of six liquid storage containers 1, siphon tubes 2, and triboelectric power generation tubes 3. Each unit uses an FEP tube 20cm long, with an inner diameter of 4mm and an outer diameter of 6mm. The siphon tube delivers a single volume of 2.55mL. The support is made of 3mm thick acrylic sheet, and the spacing between adjacent units is approximately 1cm to prevent mutual interference.

[0090] Electrical connection: The output terminals of the six units are connected in parallel, the positive terminals (external electrodes) of each unit are connected to each other, and the negative terminals (internal electrodes) are connected to each other, all connected to the external circuit.

[0091] The open-circuit voltage of the array was measured using an oscilloscope, and the results showed that: Figure 17 As shown, under transient current operating conditions, the array output voltage can still be maintained above 4000V, indicating that parallel integration does not affect power generation performance. Figure 18 As shown in (a), the array can simultaneously light up nine 6W LEDs, or as shown in (a). Figure 18 (b) shows four 8W commercial lamps connected in series, producing bright flashing light, which verifies the high instantaneous power output capability of the present invention.

[0092] Example 4 This embodiment applies a power generation device to self-powered rainfall monitoring, constructing a rain gauge that requires no external power source. A filter funnel and a collection funnel together form a rainwater collector, with the filter funnel determining the effective catchment area. The FEP tube is 6cm long, with an inner diameter of 4mm and an outer diameter of 6mm, and the siphon tube delivers 0.85mL of water per cycle.

[0093] Rainwater enters the storage container through a filter funnel. When the liquid level exceeds the top of the siphon tube, the siphon is activated, and the liquid is transported to the triboelectric generator tube, generating electrical pulses. Each siphon event corresponds to a fixed drainage volume (0.85 mL), therefore the number of electrical pulses is linearly related to the amount of rainfall.

[0094] like Figure 19 As shown, the drainage volume of ten consecutive siphon events was recorded. The total drainage volume was 8.5 ± 0.1 mL, and the average drainage volume per event was 0.85 mL. The small fluctuation range indicates good drainage stability.

[0095] like Figure 20 As shown, the number of electrical pulses output was recorded under simulated rainfall intensities. The results indicate that the number of pulses is positively correlated with rainfall intensity, and the pulse density increases with increasing rainfall intensity. Based on the catchment area (… A =π( d / 2) 2 , d=174mm) and a single drainage volume (0.85mL), the rainfall depth corresponding to each electrical pulse is calculated to be 0.036mm, which is the inherent resolution of the rain gauge.

[0096] Within a wide dynamic range from light rain to heavy rain, such as Figure 21 As shown, the cumulative rainfall depth measured by the rain gauge in this embodiment is compared with the reference value. The results show that the two values ​​are in high agreement, verifying the quantitative monitoring accuracy of this rain gauge across the entire measurement range.

[0097] Rainwater harvesting provides the energy for the siphon drive, and the electrical pulse output serves both as a rainfall signal and as power for subsequent signal processing circuits (such as the wireless transmission module). Compared to traditional rain gauges, this embodiment requires no external power supply or mechanical triggering mechanism, is simple in structure, maintenance-free, and suitable for deployment in remote areas.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A solid-liquid triboelectric nanogenerator method based on flow regime control, characterized in that, A solid-liquid triboelectric nano-power generation device based on flow state control is adopted. The power generation device includes a liquid storage container (1), a siphon tube (2) is set on the liquid storage container (1), one end of the siphon tube (2) is placed inside the liquid storage container (1), and the other end is located outside the liquid storage container (1) and connected to a triboelectric tube (3). An external electrode (4) is wound on the outer wall of the triboelectric tube (3), and an internal electrode (5) is inserted into the inner side of the lower end of the triboelectric tube (3). Both the internal electrode (5) and the external electrode (4) are connected to an external circuit. The method includes: The liquid storage container (1) is drained into the triboelectric tube (3) through the siphon tube (2); By controlling the liquid supply conditions, a liquid column flow state with continuous liquid column flow, a transitional flow state with alternating liquid droplet flow and liquid column flow, or a liquid droplet flow state with discrete liquid droplet flow can be formed in the triboelectric tube (3). Select a triboelectric tube (3) with the corresponding length and cross-sectional dimensions to obtain the required power output; Under the liquid column flow state, the liquid injection flow rate is less than the steady-state discharge flow rate of the siphon tube, and the siphon process can be interrupted periodically and naturally; under this flow state, the liquid passes through the friction generator tube in the form of a continuous and complete liquid column. Under the transitional flow state, the liquid injection flow rate is between that of the liquid column flow state and the liquid droplet flow state, and the siphon process can still be interrupted intermittently; under this flow state, the liquid in the triboelectric tube (3) exhibits an unsteady flow pattern in which liquid column flow and liquid droplet flow alternate; In the droplet flow state, the liquid injection flow rate is greater than the steady-state discharge flow rate of the siphon tube (2), and the siphon process continues to run without interruption; in this flow state, the liquid passes through the triboelectric tube (3) in the form of discrete droplets. The liquid injection flow rate is adjusted according to the length of the triboelectric tube (3) to achieve the above-mentioned flow state conversion; wherein, the longer the triboelectric tube, the smaller the critical injection flow rate required to make the flow state conversion.

2. The solid-liquid triboelectric nanogenerator method based on flow regime control according to claim 1, characterized in that, The volume corresponding to the area where the outer electrode (4) of the triboelectric tube (3) is wound is matched with the volume of liquid discharged by the siphon tube (2) in a single flow state under liquid column flow conditions. The length of the triboelectric tube (3) is selected according to the required output voltage. The higher the required output voltage, the longer the selected triboelectric tube (3) should be.

3. A solid-liquid triboelectric nanogenerator based on flow regime control, used to implement the solid-liquid triboelectric nanogenerator method based on flow regime control as described in any one of claims 1-2, characterized in that, It includes a support (6) and a liquid storage container (1), wherein the liquid storage container (1) is fixedly installed on the support (6).

4. The solid-liquid triboelectric nanogenerator based on flow regime control according to claim 3, characterized in that, A collection funnel (7) is also fixedly installed on the bracket (6). The collection funnel (7) is located above the liquid storage container (1), and the inlet of the liquid storage container (1) is located directly below the outlet of the collection funnel (7).

5. A solid-liquid triboelectric nanogenerator based on flow regime control according to claim 4, characterized in that, A filter funnel (8) is also fixedly installed on the bracket (6), and the filter funnel (8) is located above the collection funnel (7).

6. The solid-liquid triboelectric nanogenerator based on flow regime control according to claim 4, characterized in that, The outlet of the collecting funnel (7) is connected to the inlet of the liquid storage container (1) through a pipeline, and a regulating valve (9) is installed on the pipeline.

7. A solid-liquid triboelectric nanogenerator based on flow regime control according to claim 3, characterized in that, The liquid storage container (1) and the siphon tube (2) are integrally molded from transparent material.

8. A solid-liquid triboelectric nanogenerator based on flow regime control according to claim 3, characterized in that, The triboelectric tube (3) is a fluorinated ethylene propylene copolymer tube or a polytetrafluoroethylene tube, the outer electrode (4) is a conductive copper foil, and the inner electrode (5) is a metal wire.

9. A solid-liquid triboelectric nanogenerator based on flow regime control according to claim 3, characterized in that, The liquid storage containers (1) are arranged in an array, and each liquid storage container (1) is provided with a corresponding siphon tube (2); the outer electrodes (4) of the triboelectric tubes (3) connected to each siphon tube (2) are connected in parallel, and the inner electrodes (5) are connected in parallel.

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