Wave energy efficient in-situ energy supply ocean profile buoy system for prolonging service time

Abstract

The invention discloses a service time improvement-oriented wave energy efficient in-situ energy supply ocean profile buoy system, which belongs to the field of ocean observation and comprises a main buoy subsystem, a floating drum subsystem and an anchoring subsystem. Wherein the main buoy subsystem is provided with an ocean profile element sensor, a communication system and the like, is used for observing an ocean profile, and is also provided with an oscillating water column wave energy conversion device for capturing long-period waves; the floating drum subsystem is provided with an oscillating water column wave energy conversion device used for capturing short-period waves, the oscillating water column wave energy conversion device is complementary with the wave energy capturing frequency band of the main buoy subsystem, and stable electric energy supply is provided for the buoy system. And the anchoring subsystem is used for anchoring the buoy system at a fixed position to guarantee fixed-point observation. According to the method, the conversion of the anchoring type ocean profile buoy from a battery dependent type to an in-situ energy supply type is promoted, the operation and maintenance cost of an ocean observation network can be remarkably reduced, and high-reliability technical support is provided for real-time monitoring of deep and far sea and early warning of extreme climate.

Description

Technical Field

[0001] This invention belongs to the field of marine observation and relates to wave energy utilization devices, especially to a high-efficiency in-situ powered wave energy ocean profiling buoy system for extending service life. Background Technology

[0002] Ocean observation, as a core means of understanding the ocean, is a key capability supporting the development of marine resources, the protection of rights and interests, and ecological governance. It is of great significance to meeting major national needs such as the security of strategic deep-sea channels and disaster prevention and mitigation.

[0003] Moored ocean profiling buoys, with their fixed-point continuous observation capabilities, can accurately acquire the vertical distribution and transport characteristics of matter and energy in specific sea areas, providing long-term continuous data support for typhoon forecasting, fisheries resource assessment, and other purposes, becoming a key infrastructure for analyzing ocean dynamic processes and ecological responses. However, moored ocean profiling buoys face challenges such as high energy consumption and inability to connect to the power grid due to their remote deployment, resulting in high maintenance costs and poor sustainability. This leads to problems such as low data collection frequency, short endurance, and difficulty in continuously operating high-energy-consuming sensors. Looking back at the development history of moored ocean profiling buoys, early buoys integrating diesel generators were gradually phased out due to their daily fuel consumption of up to 10 liters and susceptibility to leakage. Although photovoltaic-cell combinations became mainstream for a period, they could not solve the problem of power interruption at night and in severe weather, and the photovoltaic equipment was susceptible to surface corrosion and salt crystallization, challenging their long-term operational reliability. While wind-solar hybrid solutions improved system power redundancy, they failed to become widespread because they increased the risk of buoy capsizing. There is an urgent need to explore new energy supply technologies to overcome the bottleneck of long-term in-situ energy supply for ocean profiling buoys.

[0004] Among diverse renewable ocean energy sources, wave energy stands out as the most promising technological pathway for in-situ ocean energy supply due to its wide distribution, high energy density, high energy grade, and long utilization period. Utilizing wave energy to achieve energy self-sufficiency for moored ocean profiling buoys can effectively improve profiling capabilities, extend operation and maintenance cycles, increase service life, and significantly enhance the buoy's ability to analyze ocean dynamic processes and ecological responses. However, directly integrating wave energy devices with ocean profiling buoys faces complex technical challenges. First, there is a fundamental contradiction between the stable observation requirements of profiling buoys and the efficient energy capture capabilities of wave energy conversion devices. To ensure the measurement accuracy of the profiling buoy, resonance of the buoy itself under wave excitation must be avoided. Therefore, the buoy's resonance period must be designed to be much shorter than the wave period. This causes the buoy to exhibit passive following characteristics under wave excitation, hindering the capture of wave energy. Furthermore, wave energy exhibits strong temporal variability, making it difficult for traditional wave-energy ocean profiling buoys to accommodate different wave conditions and achieve efficient and stable power generation. Summary of the Invention

[0005] This invention discloses a high-efficiency in-situ powered wave energy ocean profiling buoy system designed to extend service life. It fundamentally solves the problem of insufficient energy self-sufficiency of traditional anchored ocean observation buoys under complex and random sea conditions, as well as the mechanistic contradiction between the still-water stability requirements of profiling observation platforms and the need for efficient wave energy capture (resonance excitation). The measurement and control system of this invention enhances the research capabilities on the flow field characteristics and hydrodynamic performance of oscillating water column wave energy conversion devices, providing a highly reliable in-situ power supply technology solution for real-time monitoring in deep-sea areas and extreme weather early warning.

[0006] To achieve the above-mentioned technical functions, the present invention adopts the following technical solution: This invention first discloses a wave energy-efficient in-situ powered ocean profiling buoy system for extending service life. The system comprises three core subsystems: a main buoy subsystem, a buoy drum subsystem, and an anchoring subsystem.

[0007] The main buoy subsystem comprises a main buoy body and oceanographic profile observation equipment. The main buoy body adopts a stepped cylindrical structure, with a lower diameter larger than the upper diameter. A first oscillating water column wave energy conversion device, containing a first air chamber, is installed along the central axis of the main buoy body. The first oscillating water column wave energy conversion device is connected to surface seawater at the bottom and to air at the top. Under long-period wave conditions, it captures wave energy and converts it into electrical energy to power the system. The oceanographic profile observation equipment is lowered to the observation position to carry out observation operations and transmit observation data to satellites or shore-based platforms. The aforementioned float subsystem includes a float body, which has a cylindrical structure with a lower diameter larger than the upper diameter. A second oscillating water column wave energy conversion device, which includes a second air chamber, is installed through the float body along its central axis. The second oscillating water column wave energy conversion device is connected to seawater at the bottom and air at the top, and captures wave energy and converts it into electrical energy under short-period wave conditions. The mooring subsystem includes connecting cables and anchor chains, and mooring anchor chains; wherein the connecting cables and anchor chains are used to connect the main buoy body and the buoy drum body, and to transmit the electrical energy generated by the second oscillating water column wave energy conversion device to the main buoy body; the mooring anchor chains connect the buoy drum body and the seabed anchor block, and are used to fix the system.

[0008] Preferably, the first oscillating water column wave energy conversion device includes a first air chamber; the first air chamber penetrates the main buoy body, gradually narrowing from the flat cylindrical section to the long cylindrical section, and forming a variable radius structure with large radii at both ends and small radii in the middle within the long cylindrical section, the middle section with reduced radius constituting the throat of the first air chamber, the diameter of the first air chamber at the water surface is 5-8m, and the draft of the main buoy body is 1-2m; the main buoy body remains basically stable under short-period wave conditions, and generates a weak wave-following motion under long-period wave drive, the water column within the radius of the first air chamber resonates under long-period wave drive, thereby driving the air above the water column to flow back and forth; an air turbine and generator are installed at the throat of the first air chamber for outputting electrical energy under the drive of the reciprocating air flow.

[0009] Preferably, the second oscillating water column wave energy conversion device includes a second air chamber; the second air chamber penetrates the float body and gradually narrows from the thick cylindrical section to the thin cylindrical section. The radius of the second air chamber at the water surface is 1.5-2m, and the draft of the float body is 1.5-2m, so that the water column inside the second air chamber will undergo inherent oscillation under the drive of short-period waves, while the float body will undergo structural resonance in the heave direction under the short-period wave conditions. Moreover, the heave of the float body structure is opposite in phase to the oscillation of the water column inside the second air chamber, driving the air above the water column inside the second air chamber to flow at high speed; an air turbine and a generator are installed at the upper end of the second air chamber for outputting electrical energy to the outside under the drive of high-speed air flow.

[0010] Preferably, the wave periods for capturing wave energy by the main buoy body and the buoy drum body are complementary to each other and cover the wave periods corresponding to the actual sea conditions, ensuring that the buoy system can generate electricity stably under any wave period conditions.

[0011] Preferably, there are multiple float bodies, which are arranged around the main buoy body to form a float body array, which serves to stabilize the position of the buoy system and capture high-frequency waves.

[0012] Preferably, the air turbine and generator include, from bottom to top, a forward fixed guide vane, a forward rotor, a reverse rotor, and a reverse fixed guide vane; both the forward and reverse fixed guide vanes include multiple inclined blades, and the airflow rotates under the action of the blades; the forward and reverse fixed guide vanes have the same inclination direction, and the forward and reverse rotors rotate in opposite directions, both used to convert fluid energy into electrical energy; guide cones are provided below the forward fixed guide vane and above the reverse fixed guide vane to increase the airflow velocity, and two generators are installed inside the guide cones, one for the forward rotor and one for the reverse rotor; driven by the airflow in and out of the air chamber, the forward and reverse rotors rotate in opposite directions, driving the generators to generate electricity.

[0013] One of the aforementioned methods for designing the float of an ocean profiling buoy system involves considering the natural inherent period of heave under wave excitation for a given float.T heave satisfy: ; In the formula, m The total mass of the floating body m 33 Add mass to the heave of the floating body. r The density of seawater, g It is the acceleration due to gravity. S r The surface area of ​​the floating body at the waterline at the still water surface; To ensure the data accuracy of the oceanographic profile observation equipment during the deployment process, the main buoy body must avoid generating violent vertical motion in short waves. Therefore, the heave-added mass of the main buoy body is increased to raise the natural heave period of the main buoy body to more than 20s. In order to fill the gap that the main buoy body cannot capture energy in short-period waves, the total mass of the buoy body and the heave-added mass are reduced to keep the natural heave period of the buoy body between 4s and 8s. For the cylindrical oscillating water column within the gas chamber, the natural period of piston-mode oscillation occurs. T 0 satisfies: ; In the formula, D The draft of the buoy. R is the radius of the air chamber at the water surface, where 0.848 is an empirical coefficient; To match the energy-harvesting frequency band of the water column in the first air chamber with long-period waves, the draft of the main buoy body is set to 1-2m, and the radius of the first air chamber at the water surface is 5-8m; to match the energy-harvesting frequency band of the water column in the second air chamber with short-period waves, the draft of the buoy body is set to 1.5-2m, and the radius of the second air chamber at the water surface is 1.5-2.5m.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) This invention innovatively solves the fundamental physical contradiction between "the observation platform needs to maintain still water stability" and "wave energy conversion requires the excitation of structural resonance" in marine observation buoys. By decoupling the macroscopic waterline parameters of the main buoy from the microscopic dimensions of the internal air chamber, the main buoy effectively avoids the excitation frequency of the main waves and achieves extremely low wave-following response. At the same time, by utilizing the added mass effect of the large-radius internal air chamber, the water column in the air chamber resonates significantly under long-period waves, thus achieving the unity of high-precision observation of "static platform and moving water column" and efficient long-wave energy capture.

[0015] (2) This invention proposes a novel frequency-response complementary broadband energy harvesting configuration based on a "main buoy-float array," which overcomes the shortcomings of traditional single oscillating water column devices, such as narrow effective bandwidth and inability to adapt to the real ocean random broadband wave spectrum. By allowing the main buoy to specifically capture low-frequency long-period waves, the float array undergoes heave and water column "double resonance" to efficiently capture high-frequency short-period waves, thus broadening the overall energy harvesting bandwidth of the system and significantly improving the reliability of in-situ power supply under low sea states and complex random wave conditions.

[0016] (3) This invention innovatively integrates a coaxial dual-rotor reversing air turbine and combines it with a wide-condition high-efficiency generator, fundamentally overcoming the bottlenecks of traditional single-rotor impulsive air turbines, such as large wake swirl energy loss and difficulty in low-pressure starting under reciprocating unsteady airflow. The counter-rotating structure effectively recovers tangential aerodynamic energy and improves aerodynamic conversion efficiency; at the same time, the counter-rotating dual-rotor system perfectly cancels the yaw gyro torque caused by high-speed operation, eliminating attitude disturbances to the buoy observation platform and further consolidating the data reliability of ocean profile measurement. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the present invention.

[0018] Figure 2 This is a partial schematic diagram of the air turbine of the present invention.

[0019] In the diagram: 1. Main buoy body, 2. First air chamber, 3. Working compartment, 4. Main buoy air turbine and generator, 5. Communication system, 6. Oceanographic profile observation equipment, 7. Buoy body, 8. Buoy air turbine and generator, 9. Second air chamber, 10. Connecting cable and anchor chain, 11. Mooring anchor chain, 12. Forward fixed guide vane, 13. Forward rotor, 14. Reverse rotor, 15. Reverse fixed guide vane, 16. Guide cone. Detailed Implementation

[0020] To facilitate understanding of the present invention, embodiments of the present invention will be described below with reference to the accompanying drawings. Those skilled in the art should understand that the following description is only for the purpose of explaining the invention and is not intended to limit its scope.

[0021] This invention addresses the challenge of long-term in-situ power supply for anchored ocean profiling buoys by innovatively proposing a wave energy-efficient in-situ power supply ocean profiling buoy system for extending service life, comprising a main buoy subsystem, a buoy drum subsystem, and an anchoring subsystem.

[0022] The main buoy subsystem includes the main buoy body 1, the working compartment 3, the communication system 5, and the oceanographic profile observation equipment 6.

[0023] The main buoy body 1 is a stepped cylindrical structure, comprising a coaxial flat cylindrical section and a long cylindrical section. The flat cylindrical section is located at the bottom and its lower part contacts the water surface. The diameter of the flat cylindrical section is larger than that of the long cylindrical section. The main buoy body 1 is equipped with an oscillating water column wave energy conversion device for capturing long-period waves. This oscillating water column wave energy conversion device for capturing long-period waves includes a first air chamber 2 and a main buoy air turbine and generator 4. The first air chamber 2 is located at the central axis of the main buoy body 1 and extends axially through the main buoy body 1. That is, the first air chamber 2 is connected to the surface seawater at the bottom and to the air at the top. The first air chamber 2 gradually narrows from the flat cylindrical section to the long cylindrical section within the main buoy body 1, and forms a variable radius structure with large radii at both ends and small radii in the middle within the long cylindrical section. The section with the reduced radius in the middle constitutes the throat of the first air chamber 2. The radius of the first air chamber 2 at the water surface is significantly larger than the diameter of the throat. This design allows the main buoy 1 to maintain basic stability under short-period wave conditions due to its large inertia and small waterline. Under long-period wave drive and nonlinear control of the anchor chain, it only produces weak wave-following motion. At the same time, the confined water within the first air chamber 2 undergoes strong piston resonance under the dynamic pressure of long-period waves, achieving asymmetric and efficient energy capture of "platform stationary, water column resonant," thereby ensuring the high-precision operation of the observation equipment. In this embodiment, the diameter of the flat cylindrical section is 15-20m, the height of the flat cylindrical section above the waterline is 0.5-1m, the diameter of the first air chamber 2 at the water surface is 5-8m, and the draft of the main buoy 1 is 1-2m. The main buoy air turbine and generator 4 are located in the throat of the first air chamber 2. Long-period waves drive the free water surface in the first air chamber 2 to oscillate violently up and down, thereby driving the air above the free water surface in the first air chamber 2 to flow back and forth. The reciprocating air flows as a carrier to drive the main buoy air turbine and generator 4 to work, outputting stable electrical energy. The draft of the main buoy body 1 is matched with the height of the flat cylindrical section to prevent the water surface from submerging the main buoy air turbine and generator 4.

[0024] The working chamber 3 adopts a circular spatial layout, surrounding the long cylindrical section of the main buoy. The oceanographic profiling equipment 6 can be selected from instruments such as a CTD (Conductivity, Temperature, Depth) meter, and is lowered to a specific water depth to observe multi-dimensional ocean data during operation. The working chamber 3 houses the necessary precision control equipment and energy management module, responsible for controlling the oceanographic profiling equipment 6 to conduct deep-sea profiling operations in undisturbed, calm water environments. The communication system 5, installed at the top of the main buoy 1, is used to transmit the observed multi-dimensional ocean data in real time to satellites or shore-based platforms, and to receive remote commands and send them to the working chamber 3 to adjust the observation strategy.

[0025] The float subsystem includes a float body 7, which is a cylindrical structure comprising a coaxial thick cylindrical section and a thin cylindrical section. The thick cylindrical section is located at the bottom, with its lower part contacting the water surface. The diameter of the thick cylindrical section is larger than that of the thin cylindrical section. The float subsystem is equipped with a specially designed oscillating water column wave energy conversion device for capturing short-period waves. This oscillating water column wave energy conversion device for capturing short-period waves includes a float air turbine and generator 8 and a second air chamber 9. The second air chamber 9 is located at the central axis of the float body 7 and extends through the float body 7 along the axis. That is, the lower part of the second air chamber 9 is connected to the surface seawater, and the upper part is connected to the air. The upper end of the second air chamber 9 is fixed to the float air turbine and generator 8. The draft of the float body 7 is matched with the height of the thick cylindrical section to prevent the water surface from submerging the float air turbine and generator 8. In this embodiment, the diameter of the thick cylindrical section is 3-4m, and the height of the thick cylindrical section is greater than 4m, with the height above the waterline being greater than 2m. The second air chamber 9 gradually narrows from the thick cylindrical section of the float body 7 to the thin cylindrical section. The second air chamber 9 has a small radius at the water surface and a shallow draft, leading to inherent fluid resonance under short-period wave conditions. Meanwhile, the float body 7, under short-period wave conditions, has its inherent motion period adjusted to match the short-period wave period, making it highly susceptible to structural resonance in the heave direction. Through the anti-phase "double resonance" mechanism of the heave of the float body 7 and the oscillation of the water column inside the second air chamber 9, extremely high relative displacement is generated under short-wave sea conditions. This drives high-speed airflow above the free water surface inside the second air chamber 9. The high-speed airflow acts as a carrier, driving the float air turbine and generator 8 to generate electricity, achieving efficient short-period energy harvesting.

[0026] Multiple float bodies 7 can be arranged to form an array around the main buoy body 1, which serves to stabilize the position of the buoy system and capture high-frequency waves. In this embodiment, the number of float bodies 7 is set to three.

[0027] The main buoy air turbine and generator 4, and the float drum air turbine and generator 8 all adopt a high aerodynamic efficiency coaxial dual-rotor reversing air turbine structure with similar configurations but different aerodynamic dimensions. The flow channel of this turbine structure includes a forward fixed guide vane 12, a forward rotor 13, a reverse rotor 14, and a reverse fixed guide vane 15 arranged sequentially from bottom to top. A guide cone 16 is provided on the upper and lower sides of the flow channel. The forward fixed guide vane 12 and the reverse fixed guide vane 15 each include multiple inclined blades. The airflow rotates under the action of the blades. The blades of the forward fixed guide vane 12 and the reverse fixed guide vane 15 have the same inclination direction. The forward rotor 13 and the reverse rotor 14 rotate in opposite directions and are both used to convert fluid energy into electrical energy. The guide cone 16 is used to increase the airflow velocity. Driven by the reciprocating high-pressure airflow in and out of the air chamber, the forward rotor 13 of the front stage generates forward rotation to do work, while the exhaust airflow with strong swirling characteristics directly impacts the reverse rotor 14 of the rear stage, allowing the reverse rotor 14 to recover swirling energy and maintain rotation in the opposite direction without additional guide structures. The forward rotor 13 and the reverse rotor 14 are each connected and drive a generator installed in the closed guide cone 16 to generate electricity in tandem. At the same time, the dual rotor system rotating in opposite directions perfectly cancels the yaw gyro torque caused by high-speed operation, eliminates attitude disturbances to the buoy system, and further consolidates the data reliability of ocean profile measurement. During the conversion of wave energy into aerodynamic energy, the equivalent aerodynamic damping coefficient of the air turbine directly determines whether the hydrodynamic radiation damping of the air chamber is in an optimal absorption state. In implementation, the system controls the pressure drop and flow characteristics of the air turbine by specifically adjusting the air turbine's flow area and rotor blade density. The equivalent damping of the air turbine is configured to be equal to the radiation damping coefficient when the oscillating water column radiates waves outward, in order to satisfy the "impedance matching" principle, prevent the water surface in the air chamber from becoming stagnant due to excessive resistance or overflowing due to insufficient resistance, and ensure wideband and efficient conversion under different wave input characteristics.

[0028] The mooring subsystem includes connecting cables and anchor chains 10 and mooring anchor chains 11. Connecting cables and anchor chains 10 connect the main buoy body 1 and the float bodies 7, serving a dual function of energy transmission and stiffness coupling: they transmit and converge the distributed AC power generated by the wave energy conversion devices of the oscillating water column on each float body 7 to the central main buoy body 1; simultaneously, they dynamically regulate the added mass, radiation damping, and relative motion response of the main buoy body 1 and the outer float body array through changes in sag profile and pretension. Mooring anchor chains 11 connect the bottom of each float body 7 to the seabed anchor block, not only physically fixing the entire buoy system in the target sea area, but also regulating the nonlinear motion response and wave energy capture efficiency of the float bodies 7 under irregular waves through changes in sag profile and pretension. The main buoy body 1, connecting cable and anchor chain 10, float array, mooring anchor chain 11 and seabed anchor block constitute a "three-anchor" configuration. This "three-anchor" configuration provides static restoring torque to resist capsizing by wind and waves. On the other hand, the reasonable spacing of the floats 7 can generate wave radiation and diffraction interference within the array when waves propagate, creating local flow field conditions for amplified wave height for the central main buoy body 1.

[0029] It should be noted that the wave frequencies at which the main buoy body 1 and the float array 7 efficiently capture wave energy can achieve precise spatial and frequency domain complementarity. The overall system design ensures that the energy absorption peak of the main buoy body 1 is located in the low-frequency long-wave band, while the absorption peak of the float array is located in the high-frequency short-wave band. The coherent superposition of the two effectively covers the broadband wave cycles corresponding to most actual complex sea states, ensuring that the buoy system can achieve all-weather, efficient, and stable in-situ power self-sufficiency under any season and any wave cycle conditions.

[0030] The present invention also provides a float design method for the aforementioned wave energy efficient in-situ functional ocean profiling buoy system aimed at extending service life, including the parameter design of the main buoy body 1 and the parameter design of the buoy body 7.

[0031] Main buoy body 1 parameter design: The main buoy 1 carries the oceanographic profile observation equipment 6. To ensure the data accuracy of the oceanographic profile observation equipment 6 during the deployment process, the main buoy 1 must avoid violent vertical movements in the waves. Simultaneously, the first air chamber 2 needs to stimulate internal water column resonance to extract energy from low-frequency, long-period waves. This necessitates the following decoupling parameter matching during the design phase: The natural period of heave of the main buoy 1 under wave excitation T heave The calculation formula depends on the total mass of the main buoy body 1, the heave-added mass, and the waterline area. In the formula, m The total mass of the main buoy body 1, m 33 The heave-added mass of the main buoy body 1, r The density of seawater, g It is the acceleration due to gravity. S r The waterline area of ​​the main buoy body 1 at the still water surface.

[0032] To avoid resonance between the main buoy body 1 and the dominant waves commonly found in the ocean (with periods typically between 6 and 12 seconds), the main buoy's... T heave Significantly moving away from this frequency band, the implementation method involves substantially increasing the heave-added mass. m 33 (Increasing inertia). Through a physical design of "large inertia and low stiffness," the heave of the main buoy body 1 naturally achieves its inherent period. T heave Increase to over 20 seconds. Since the frequency of the ambient waves is much higher than the natural frequency of the main buoy 1 at this time, the main buoy 1 exhibits excellent still water characteristics under normal wave conditions and does not experience significant heaving motion.

[0033] Assuming the main buoy 1 is essentially stationary, the first air chamber 2 at its center needs to resonate with long-wavelength waves. For a cylindrical oscillating water column, the natural period of piston-mode oscillation within the water column of the first air chamber 2... T 0 can be calculated using a modified formula: In the formula, D The draft of the main buoy body 1, R denoted as the radius of the first air chamber 2 at the water surface, where 0.848 is an empirical coefficient.

[0034] In order to match the efficient energy-harvesting frequency band of the water column in the first air chamber 2 with long-period waves (the period is usually between 9 and 15 seconds), the main buoy body 1 is designed to have a large draft. D And, while meeting the overall size requirements of the main buoy body 1, maximize the radius of the first air chamber 2 at the water surface. R The resulting large additional length significantly elongates the natural period of water oscillation within the first air chamber 2. T 0. In this embodiment, the draft of the main buoy 1 is... D The radius of the first air chamber 2 at the water surface is 1-2m, and the radius R is 5-8m.

[0035] Based on the above parameter design, when the incident wave enters the bottom of the main buoy body 1, the main buoy body 1 remains stable due to its extremely large inertia, while the water in the first air chamber 2 inside is excited to undergo large-amplitude piston oscillation due to its similar period, thus achieving a perfect integration of the "static water platform" and "dynamic water column" required for observation.

[0036] Floating drum body 7-parameter design: The outer array of float bodies is responsible for filling the gap in the main buoy body 1's inability to efficiently capture energy in the short-period high-frequency wave band. Therefore, in contrast to the main buoy body 1's pursuit of stability, the design of the float body 7 implements an aggressive "float-water column" dual-resonance coupling mechanism.

[0037] The high-frequency resonance of the float body 7 is designed to handle short-period waves with periods of 4 to 8 seconds. The float body 7 employs an extremely shallow draft and a flattened cross-section. (Refer to the above...) T heave The formula reduces the total mass of the float 7 and the heave-added mass of the float 7 (reducing the moment of inertia), so that the natural heave period of the float 7 is precisely adjusted to the 4s to 8s frequency band, causing the float 7 to produce violent up-and-down fluctuations when short-period waves arrive.

[0038] Simultaneously, for the second air chamber 9 inside the floating drum, refer to T The calculation formula, by reducing the draft of the float 7 and shrinking the bottom radius of the second air chamber 9, ensures that the natural period of water oscillation within the second air chamber 9 also falls within the range of 4s to 8s. In this embodiment, the draft of the float 7 is 1.5-2m, and the radius of the second air chamber 9 at the water surface is 1.5-2.5m.

[0039] During operation, when short-period waves arrive, the float 7 rises sharply upwards, while the water column inside its second air chamber 9 may be in a downward phase relative to the float 7 due to inertia and damping. This "strong relative motion of opposite phases" between the structural heave and the water column oscillation causes the volume of the closed air chamber to be compressed or expanded rapidly in an instant, thereby generating extremely high instantaneous air pressure velocity and significantly improving the energy capture and conversion efficiency under short-period sea states.

[0040] The main buoy subsystem designed in this invention is specifically designed to capture long-period waves, while the buoy drum subsystem is specifically designed to capture short-period waves. This overcomes the contradiction between stable observation functions and improved energy capture efficiency, and enhances adaptability to a wide range of sea states, achieving stable and efficient energy capture. This invention promotes the transformation of anchored ocean profiling buoys from "battery-dependent" to "in-situ powered," significantly reducing the operation and maintenance costs of ocean observation networks. Furthermore, through all-weather, high-resolution data acquisition, it provides highly reliable technical support for real-time monitoring of deep-sea areas and early warning of extreme weather conditions. It has significant engineering value and scientific significance for achieving the strategic goal of a "transparent ocean," and will provide crucial support for the leapfrog development of my country's ocean observation technology.

[0041] Based on the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept, all of which are within the scope of protection of this invention. Matters not covered in this invention are common knowledge to those skilled in the art.

Claims

1. A wave energy-efficient in-situ powered ocean profiling buoy system for extending service life, characterized in that, This includes the main buoy subsystem, the buoy subsystem, and the mooring subsystem; The main buoy subsystem comprises a main buoy body and oceanographic profile observation equipment. The main buoy body adopts a stepped cylindrical structure, with a lower diameter larger than the upper diameter. A first oscillating water column wave energy conversion device, containing a first air chamber, is installed along the central axis of the main buoy body. The first oscillating water column wave energy conversion device is connected to surface seawater at the bottom and to air at the top. Under long-period wave conditions, it captures wave energy and converts it into electrical energy to power the system. The oceanographic profile observation equipment is lowered to the observation position to carry out observation operations and transmit observation data to satellites or shore-based platforms. The aforementioned float subsystem includes a float body, which has a cylindrical structure with a lower diameter larger than the upper diameter. A second oscillating water column wave energy conversion device, which includes a second air chamber, is installed through the float body along its central axis. The second oscillating water column wave energy conversion device is connected to seawater at the bottom and air at the top, and captures wave energy and converts it into electrical energy under short-period wave conditions. The mooring subsystem includes connecting cables and anchor chains, and mooring anchor chains; The connecting cable and anchor chain are used to connect the main buoy body and the buoy drum body, and to transmit the electrical energy generated by the second oscillating water column wave energy conversion device to the main buoy body; the mooring anchor chain connects the buoy drum body and the seabed anchor block, and is used to fix the system.

2. The ocean profiling buoy system according to claim 1, characterized in that, The main buoy body includes a lower flat cylindrical section and an upper long cylindrical section. The diameter of the flat cylindrical section is 15-20m, and the height above the waterline is 0.5-1m.

3. The ocean profiling buoy system according to claim 2, characterized in that, The first oscillating water column wave energy conversion device includes a first air chamber. The first air chamber penetrates the main buoy body, gradually narrowing from a flat cylindrical section to a long cylindrical section, and forming a variable radius structure with large radii at both ends and a small radius in the middle within the long cylindrical section. The narrowing section in the middle constitutes the throat of the first air chamber. The diameter of the first air chamber at the water surface is 5-8m, and the draft of the main buoy body is 1-2m. The main buoy body remains basically stable under short-period wave conditions, and generates a weak wave-following motion under the drive of long-period waves. The water column within the radius of the first air chamber resonates under the drive of long-period waves, thereby driving the air above the water column to flow back and forth. An air turbine and a generator are installed at the throat of the first air chamber to output electrical energy driven by the reciprocating air flow.

4. The ocean profiling buoy system according to claim 1, characterized in that, The floating drum body includes a lower thick cylindrical section and an upper thin cylindrical section; the diameter of the thick cylindrical section is 3-4m, and the height of the thick cylindrical section is greater than 4m, of which the height above the waterline is greater than 2m, in order to avoid the water surface submerging the air turbine.

5. The ocean profiling buoy system according to claim 4, characterized in that, The second oscillating water column wave energy conversion device includes a second air chamber. The second air chamber penetrates the float body and gradually narrows from the thick cylindrical section to the thin cylindrical section. The radius of the second air chamber at the water surface is 1.5-2m, and the draft of the float body is 1.5-2m. This causes the water column inside the second air chamber to oscillate naturally under the drive of short-period waves, while the float body undergoes structural resonance in the heave direction under short-period wave conditions. The heave of the float body structure is opposite in phase to the oscillation of the water column inside the second air chamber, driving the air above the water column inside the second air chamber to flow at high speed. An air turbine and a generator are installed at the upper end of the second air chamber to output electrical energy externally under the drive of high-speed air flow.

6. The ocean profiling buoy system according to claim 1, characterized in that, The wave periods of the main buoy body and the buoy drum body that capture wave energy are complementary to each other and cover the wave periods corresponding to the actual sea conditions, ensuring that the buoy system can generate electricity stably under any wave period conditions.

7. The ocean profiling buoy system according to claim 1, characterized in that, The float body consists of multiple float bodies arranged around the main buoy body to form a float body array, which serves to stabilize the position of the buoy system and capture high-frequency waves.

8. The ocean profiling buoy system according to claim 2, characterized in that, The first oscillating water column wave energy conversion device is fixed with a communication system at its upper end, which is used to receive observation data from the ocean element profile observation equipment and send it to a satellite or shore-based platform and receive remote commands; a working chamber is set around the long cylindrical section surrounding the main buoy body, and the working chamber is equipped with control equipment and energy management module, which is used to control the ocean element profile observation equipment to carry out observation operations according to the remote commands received by the communication system.

9. The ocean profiling buoy system according to claim 3 or 5, characterized in that, The air turbine and generator include, from bottom to top, a forward fixed guide vane, a forward rotor, a reverse rotor, and a reverse fixed guide vane. Both the forward and reverse fixed guide vanes include multiple inclined blades, and the airflow rotates under the action of the blades. The forward and reverse fixed guide vanes are inclined in the same direction, and the forward and reverse rotors rotate in opposite directions, both used to convert fluid energy into electrical energy. A guide cone is provided below the forward fixed guide vane and above the reverse fixed guide vane to increase the airflow velocity. Two generators are installed inside the guide cone, with one generator connected to each of the forward and reverse rotors. Driven by the airflow in and out of the air chamber, the forward and reverse rotors rotate in opposite directions, driving the generators to generate electricity.

10. A method for designing the float of a marine profiling buoy system according to any one of claims 1-9, characterized in that, For a floating body, its natural period of heave under wave excitation T heave satisfy: ； In the formula, m The total mass of the floating body μ 33 Add mass to the heave of the floating body. ρ The density of seawater, g It is the acceleration due to gravity. S r The surface area of ​​the floating body at the waterline at the still water surface; To ensure the data accuracy of the oceanographic profile observation equipment during the deployment process, the main buoy body needs to avoid violent vertical motion in short waves. Therefore, the heave-added mass of the main buoy body is increased to raise the natural heave period of the main buoy body to more than 20s. In order to fill the gap that the main buoy body cannot capture energy in short-period waves, the total mass of the buoy body and the heave-added mass are reduced to keep the natural heave period of the buoy body between 4s and 8s. For the cylindrical oscillating water column inside the gas chamber, the natural period of piston-mode oscillation occurs. T 0 satisfies: ； In the formula, D The draft of the buoy. R is the radius of the air chamber at the water surface, where 0.848 is an empirical coefficient; To match the energy-harvesting frequency band of the water column in the first air chamber with long-period waves, the draft of the main buoy body is set to 1-2m, and the radius of the first air chamber at the water surface is 5-8m; to match the energy-harvesting frequency band of the water column in the second air chamber with short-period waves, the draft of the buoy body is set to 1.5-2m, and the radius of the second air chamber at the water surface is 1.5-2.5m.

Images