A resonant nonlinear wave making system for artificial wave pools and a method of designing the same

Abstract

The application relates to a resonance nonlinear wave making system for an artificial surfing pool and a design method thereof, and the system comprises a plurality of wave making units arranged along a preset axis of the wave making pool; any wave making unit comprises an electrical control subsystem, a variable frequency air blower, a static pressure chamber, an air chamber and a resonance subsystem; the electrical control subsystem is used for controlling the variable frequency air blower to continuously output compressed gas to the static pressure chamber and controlling the compressed gas in the static pressure chamber to be injected into the air chamber; the air chamber is surrounded by a cavity and a top surface of an oscillating water column and is used for continuously extruding the oscillating water column according to internal pressure until the water extruding time reaches a preset time; the resonance subsystem comprises a backward bend pipe which is curved towards the water surface at the tail end, is horizontal at the middle and has an adjustable length of the horizontal section, the head end of the backward bend pipe is communicated with the bottom of the cavity, the tail end is communicated with the wave making pool, is used for guiding the oscillating water column to the wave making pool to realize wave making, and is used for adjusting the guiding length of the oscillating water column by adjusting the length of the horizontal section to realize the resonance of the oscillating water column.

Description

Technical Field

[0001] This application relates to the field of artificial wave generation technology, and in particular to a resonant nonlinear wave generation system for artificial surfing pools and its design method. Background Technology

[0002] With the rapid development of the water sports industry, surfing has gained widespread popularity due to its excitement and fun. However, the instability and unpredictability of natural ocean waves hinder the advancement of competitive surfing techniques, making the demand for professional, safe, and efficient artificial wave pools increasingly urgent. Since artificial wave generation is energy-intensive, the electricity cost for wave generation in pneumatic artificial wave pools accounts for over 50% of their operating costs. Therefore, improving the wave generation efficiency and reducing the cost per wave in pneumatic artificial wave pools are crucial for enhancing the efficiency and profitability of artificial wave pool technology, as well as mitigating its technical and economic risks.

[0003] Existing traditional pneumatic wave generators are limited by their inherent structural frequencies. Under reasonable engineering constraints and cost limitations, they can only achieve simple water-driven wave generation, failing to create a resonance matching mechanism with a frequency range similar to the natural period of ocean waves. This results in insufficient effective length of the oscillating water column, leading to short wave periods that cannot meet the core requirement of professional surfing for long-period waves. Furthermore, they suffer from significant energy loss, resulting in high energy costs. For existing vertical tube pneumatic wave generators, the typical natural period range is 3-6 seconds, far exceeding the common range of 8-20 seconds for surfable natural swells in the ocean. Achieving an 8-second natural period using traditional vertical tube pneumatic wave generators requires a vertical tube depth greater than 17 meters. This significantly increases the required pool depth, technical complexity, and the significantly higher costs associated with deep foundation pits and civil engineering, necessitating a substantial increase in the area of ​​the artificial wave pool.

[0004] Therefore, there is an urgent need for a new wave-generating system that can significantly reduce energy consumption and operating costs, and stably generate long-period nonlinear waves that meet the needs of professional surfing. Summary of the Invention

[0005] To address the shortcomings of traditional vertical tubular air pressure wave generators, it is necessary to provide a novel wave generator system that aims to achieve precise resonance matching between oscillating water columns and artificial high-quality surfable waves, stably generate long-period nonlinear waves that meet the needs of professional surfing, and significantly reduce energy loss and operating costs. Specifically, this involves a resonant nonlinear wave generator system for artificial surf pools and its design method.

[0006] On the one hand, a resonant nonlinear wave generation system for artificial surfing pools is provided, comprising: Several wave-making units are arranged along a preset axis of the wave pool. During wave generation, each wave-making unit is triggered sequentially according to a preset time sequence to generate waves of several different wave types. Each wave-making unit includes: an electrical control subsystem, a variable frequency blower, a static pressure chamber, an air chamber, and a resonance subsystem. The electrical control subsystem is used to control the variable frequency blower to continuously output compressed gas to the static pressure chamber, and to control the injection of compressed gas in the static pressure chamber into the gas chamber; The air chamber is formed by the cavity and the top surface of the oscillating water column, and is used to continuously squeeze the oscillating water column according to the internal pressure until the water pressure time reaches the preset time. The resonant subsystem includes a backward-curved pipe that bends towards the water surface at one end, is horizontal in the middle, and has an adjustable horizontal section length. The first end of the backward-curved pipe is connected to the bottom of the cavity, and the second end is connected to the wave pool. It is used to guide the oscillating water column to the wave pool to generate waves, and to adjust the guiding length of the oscillating water column by adjusting the length of the horizontal section to achieve resonance of the oscillating water column.

[0007] Preferably, the electrical control subsystem further includes a real-time frequency conversion adjustment signal for generating working parameters based on the acquired speed of the frequency converter blower, the pressure of the static pressure chamber, the pressure of the air chamber, and the preset target working pressure, and transmitting it to the frequency converter blower. The variable frequency blower is connected to the electrical control subsystem and is connected to the air inlet of the static pressure chamber through an air supply pipeline. The variable frequency blower is used to adjust the operating parameters according to the real-time variable frequency adjustment signal and continuously output compressed gas to the static pressure chamber.

[0008] Preferably, the electrical control subsystem further includes a pressure relief valve for generating a pressure relief signal and transmitting it to the static pressure chamber when the pressure in the static pressure chamber reaches a preset pressure. The static pressure chamber is connected to the gas chamber via the pressure relief valve, which is used to open the pressure relief valve according to the pressure relief signal to inject compressed gas into the gas chamber.

[0009] Preferably, it also includes a sensor subsystem, which includes: a static pressure chamber pressure sensor arranged in the static pressure chamber and a gas chamber pressure sensor arranged in the gas chamber; The static pressure chamber pressure sensor is electrically connected to the electrical control subsystem and is used to monitor the pressure of the static pressure chamber in real time and transmit it to the electrical control subsystem. The air chamber pressure sensor is electrically connected to the electrical control subsystem and is used to monitor the air chamber pressure in real time and transmit the data to the electrical control subsystem.

[0010] Preferably, the electrical control subsystem further includes an exhaust valve for generating an exhaust signal and transmitting it to the air chamber when the water pressure duration reaches the water pressure stroke duration; The air chamber is connected to the outside atmosphere through the exhaust valve, which is used to open the valve to exhaust air according to the exhaust signal.

[0011] Preferably, the static pressure chamber is provided with a first pressure limiting valve, through which the static pressure chamber is connected to the outside atmosphere; the air chamber is provided with a second pressure limiting valve, through which the air chamber is connected to the outside atmosphere; both the first pressure limiting valve and the second pressure limiting valve are electrically connected to the electrical control subsystem, and the electrical control subsystem further includes a function to control the first pressure limiting valve and / or the second pressure limiting valve to exhaust gas when the operating pressure of the variable frequency blower reaches 90%-98% of a preset stall threshold.

[0012] Preferably, the electrical control subsystem further includes a function for generating a length adjustment signal based on the target resonance period and transmitting it to the resonance subsystem; The resonant subsystem is used to adjust the length of the horizontal segment according to the length adjustment signal.

[0013] Preferably, the resonant subsystem further includes: a back bend actuator, a tailpipe guide plate, a rigid baffle plate, and a tailpipe actuator; The back-bend actuator is installed on the top surface of the horizontal section of the back-bend. One end of the back-bend actuator is fixed to the top surface of the curved part extending from the bottom of the cavity away from the static air chamber toward the wave pool, and the other end is fixedly connected to the rigid baffle. A retractable baffle is arranged on the bottom surface of the back-bend actuator as the top surface of the horizontal section of the back-bend. The back-bend actuator is used to adjust the length of the retractable baffle according to the length adjustment signal to realize the adjustment of the horizontal section length. The bottom of the horizontal section of the back bend pipe away from the cavity is movably connected to the tailpipe guide plate. The tailpipe guide plate and the rigid baffle plate form a curved guide tailpipe structure. The back bend pipe is connected to the wave pool through the guide tailpipe structure at the end, and is used to guide the oscillating water column to the wave pool to realize wave generation. One end of the tailpipe actuator is fixed to the bottom structure of the wave pool facing the tailpipe guide plate, and the other end is fixed to the plane of the tailpipe guide plate facing the bottom structure. It is used to move the tailpipe guide plate synchronously when the back bend actuator moves, so as to keep the geometric dimensions of the guide tailpipe structure unchanged.

[0014] Preferably, the resonant subsystem further includes: a backbend actuator, a U-tube, and a tailpipe actuator; One end of the back-bend actuator is fixed to the top surface of the bend extending from the bottom of the cavity away from the static air chamber toward the wave pool, and the other end extends or shortens toward the wave pool. The bottom surface of the back-bend actuator is provided with a retractable baffle as the top surface of the horizontal section of the back-bend. The back-bend actuator is used to adjust the length of the retractable baffle according to the length adjustment signal to realize the adjustment of the length of the horizontal section. The bottom of the horizontal section of the back bend is movably connected to the U-shaped tube at the end away from the cavity. The U-shaped tube is recessed toward the back bend actuator. The U-shaped tube and the back bend actuator form a curved guide tail pipe structure. The back bend is connected to the wave pool through the guide tail pipe structure at the end, and is used to guide the oscillating water column to the wave pool to generate waves. One end of the tailpipe actuator is fixed to the bottom structure of the wave pool facing the U-shaped tube, and the other end is fixed to the U-shaped tube facing the bottom structure. It is used to move the U-shaped tube synchronously when the back-bend actuator moves, so as to keep the geometric dimensions of the guide tailpipe structure unchanged.

[0015] On the other hand, a design method for the aforementioned resonant nonlinear wave-generating system for artificial surfing pools is provided, including determining the adjustment length of the horizontal section of the back bend based on the target resonance period: Step 1: Obtain the target resonance period and the initial values ​​of the free liquid surface area, vertical cross-sectional area, horizontal cross-sectional area, total length of the vertical part, and total length of the horizontal part of the oscillating water column in the air chamber; Step 2: Based on the initial values ​​of the free surface area, vertical cross-sectional area, horizontal cross-sectional area, total length of the vertical part, and total length of the horizontal part of the oscillating water column, perform fluid dynamics numerical simulation under different water depth conditions to obtain the actual resonance period range; Step 3: Divide the upper and lower bounds of the actual resonance period by the target resonance period to obtain the upper and lower bounds of the resonance period variation coefficient; Step 4: Based on the upper and lower bounds of the resonance period variation coefficient, the free liquid surface area, vertical cross-sectional area, horizontal cross-sectional area, and total vertical length of the oscillating water column, and the target resonance period, calculate the actual range of the total horizontal length of the oscillating water column when resonance is achieved. Step 5: Subtract the initial value of the total length of the horizontal section from the actual value range of the total length of the horizontal section to obtain the adjustment length range of the horizontal section of the back bend. Based on the adjustment length range, adjust the initial value of the total length of the horizontal section of the oscillating water column to the actual value range of the total length of the horizontal section to achieve resonance of the oscillating water column under different water depth conditions.

[0016] Beneficial effects: This method adjusts the guide length of the oscillating water column by setting an adjustable horizontal section. Compared with traditional pneumatic wave generators, it directly increases the total length of the guide pipe of the oscillating water column, thereby dynamically improving the quality of the oscillating water column. It also controls the natural frequency of the pneumatic wave generator system, achieving more efficient resonant wave generation than existing artificial wave generation technologies. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application 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 only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the resonant nonlinear wave-generating system in the embodiments of this application.

[0019] Figure 2 This is a side cross-sectional view of the wave-generating unit excluding the U-shaped tube in the embodiments of this application.

[0020] Figure 3 This is a side cross-sectional view of the wave-generating unit including a U-shaped tube in an embodiment of this application.

[0021] Figure 4 This is a flowchart of the design method for the resonant nonlinear wave-generating system in the embodiments of this application.

[0022] Explanation of reference numerals in the attached figures: 1-Wave-making unit; 2-Wave pool; 3-Electrical control subsystem; 4-Variable frequency blower; 5-Static pressure chamber; 6-Air chamber; 7-Cavity; 8-Oscillating water column; 9-Back bend; 10-Gas pipeline; 11-Pressure relief valve; 12-Static pressure chamber pressure sensor; 13-Air chamber pressure sensor; 14-Exhaust valve; 15-First pressure limiting valve; 16-Second pressure limiting valve; 17-Back bend actuator; 18-Tailpipe guide plate; 19-Rigid baffle; 20-Tailpipe actuator; 21-Retractable baffle; 22-Tailpipe structure; 23-U-shaped pipe. Detailed Implementation

[0023] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0025] like Figure 1 As shown, this embodiment provides a resonant nonlinear wave generation system for artificial surfing pools, including: Several wave-making units 1 are arranged along a preset axis of the wave pool 2. During wave generation, each wave-making unit 1 is triggered sequentially according to a preset time sequence to generate waves of several different wave types. Any one of the wave-making units 1 includes: an electrical control subsystem 3, a variable frequency blower 4, a static pressure chamber 5, an air chamber 6, and a resonance subsystem.

[0026] The electrical control subsystem 3 is used to control the variable frequency blower 4 to continuously output compressed gas to the static pressure chamber 5, and to control the injection of compressed gas in the static pressure chamber 5 into the gas chamber 6.

[0027] In some preferred embodiments, multiple wave-generating units 1, after completing their design, are arranged in an orderly manner along a preset axis of the wave pool 2. Each wave-generating unit 1 receives a coordinated control signal and can share a static pressure chamber 5 in groups. During wave generation, under the control of the electrical control subsystem 3, each wave-generating unit 1 is triggered sequentially according to a preset time sequence to generate a propulsion wave that propagates stably in a specific direction. After the wave pool 2 adapts to terrain disturbances, nonlinear distortion of the wave surface can be achieved, evolving into several strongly nonlinear surfable waveforms that meet the needs of professional surfing. The system reduces energy loss through resonance effects, ensuring wave quality, stability, and economy.

[0028] Specifically, the electrical control subsystem 3 also includes a real-time variable frequency adjustment signal for generating working parameters based on the obtained speed of the variable frequency blower 4, the pressure of the static pressure chamber 5, the pressure of the air chamber 6, and the preset target working pressure, using a PID control algorithm and transmitting it to the variable frequency blower (4), so as to achieve millisecond-level precise sequence actuation control; The variable frequency blower 4 is connected to the electrical control subsystem 3 and is connected to the air inlet of the static pressure chamber 5 through the gas pipeline 10. The variable frequency blower 4 is used to adjust the working parameters according to the real-time variable frequency adjustment signal and continuously output compressed gas to the static pressure chamber 5.

[0029] In some alternative embodiments, a control algorithm similar in principle to high-frequency PID closed-loop control can also be used to generate real-time variable frequency adjustment signals to achieve precise sequential actuation control at the millisecond level.

[0030] In this embodiment, the variable frequency blower 4 adopts a variable frequency controllable design, which can precisely adjust the output flow rate and pressure. The operating parameters include the operating frequency and output power. By dynamically adjusting the operating frequency and output power of the variable frequency blower 4, blade stall of the blower 4 is avoided. At the same time, the flow rate and pressure are dynamically adjusted according to the output power history curve provided by the electrical control subsystem 3, thereby reducing energy waste. The gas transmission pipeline 10 uses high-strength sealing pipe material to ensure the sealing and stability of compressed gas transmission.

[0031] It is worth noting that the wave-making unit 1 also includes a sensor subsystem, which includes: a static pressure chamber pressure sensor 12 arranged in the static pressure chamber and an air chamber pressure sensor 13 arranged in the air chamber. The static pressure chamber pressure sensor 12 is electrically connected to the electrical control subsystem 3 and is used to monitor the pressure of the static pressure chamber 5 in real time and transmit it to the electrical control subsystem 3. The air chamber pressure sensor 13 is electrically connected to the electrical control subsystem 3 and is used to monitor the pressure of the air chamber 6 in real time and transmit it to the electrical control subsystem 3.

[0032] Furthermore, the electrical control subsystem 3 also includes a pressure relief valve 11 for generating a pressure relief signal and transmitting it to the static pressure chamber 5 when the pressure in the static pressure chamber 5 reaches a preset pressure. The static pressure chamber 5 is a pressure-resistant sealed cavity. The static pressure chamber 5 is connected to the gas chamber 6 through the pressure relief valve 11, which is used to open the pressure relief valve 11 according to the pressure relief signal to inject compressed gas into the gas chamber 6.

[0033] The air chamber 6 is formed by the cavity 7 and the top surface of the oscillating water column 8, and is used to continuously compress the oscillating water column 8 according to the internal pressure until the water pressure duration reaches a preset time. The cavity 7 is a pressure-resistant and sealed cavity used to contain compressed gas and the oscillating water column 8, and to form a pressure difference.

[0034] It is worth noting that the electrical control subsystem 6 also includes an exhaust valve 14 for generating an exhaust signal and transmitting it to the air chamber 6 when the water pressure duration reaches the preset water pressure stroke duration; The air chamber 6 is connected to the outside atmosphere through the exhaust valve 14, which is used to open the valve to exhaust air according to the exhaust signal.

[0035] In some embodiments, the pressurization time is obtained by a timer arranged on the side wall of the cavity 7 within the air chamber 6, which contacts the top surface of the oscillating water column 8. The timer is used to obtain the pressurization time and transmit it to the electrical control subsystem 3. The method for determining the preset pressurization stroke duration includes: pre-calibrating the range during the design phase through computational fluid dynamics simulation or scaled-down physical model tests, and after the wave-generating system is installed and constructed, conducting in-situ calibration to accurately determine the pressurization stroke duration value corresponding to different wave types.

[0036] In this embodiment, a first pressure-limiting valve 15 is provided on the static pressure chamber 5, and the static pressure chamber 5 is connected to the outside atmosphere through the first pressure-limiting valve 15; a second pressure-limiting valve 16 is provided on the air chamber 6, and the air chamber 6 is connected to the outside atmosphere through the second pressure-limiting valve 16; both the first pressure-limiting valve 15 and the second pressure-limiting valve 16 are electrically connected to the electrical control subsystem 3, and the electrical control subsystem 3 further includes a function to control the first pressure-limiting valve 15 and / or the second pressure-limiting valve 16 to exhaust gas when the operating pressure of the variable frequency blower 4 approaches a preset stall threshold. The operating pressure of the variable frequency blower 4 is measured and acquired in real time by a pressure sensor (not shown in the figure) installed on the air supply pipeline 10, and transmitted to the electrical control subsystem 3.

[0037] In some embodiments, the working pressure approaching the preset stall threshold includes: the working pressure reaching 90%-98% of the preset stall threshold. The preset stall threshold is calibrated by conducting field tests after construction and installation.

[0038] By equipping the static pressure chamber 5 with a static pressure sensor 12 and a first pressure limiting valve 15, the air pressure remains relatively constant throughout the process, avoiding energy waste and additional vibration losses caused by transient blade stall in the variable frequency blower 4. By equipping the air chamber 6 with an air chamber pressure sensor 13, an exhaust valve 14, and a second pressure limiting valve 16, the exhaust valve 14 enables the energy conversion from potential energy to kinetic energy during the exhaust stroke, completing the oscillation cycle. The two pressure limiting valves prevent surge caused by the pressure in the air chamber 6 exceeding the pressure in the static pressure chamber 5, thereby reducing energy waste.

[0039] It is worth noting that the main technical features of the exhaust valve 14 are rapid operation, good airtightness, and the exhaust area calculated based on the effective exhaust diameter is not less than 15% of the inner surface area of ​​the air chamber top cover, so as to minimize the additional damping and energy loss caused by the air jet during the exhaust stroke.

[0040] The resonant subsystem includes a backward-curved pipe 9 that bends towards the water surface at its end, is horizontal in the middle, and has an adjustable horizontal section length. The backward-curved pipe 9 is made of corrosion-resistant high-strength pipe or concrete, and its end adopts an arc-shaped bending structure. The first end of the backward-curved pipe 9 is connected to the bottom of the cavity 7, and the second end is connected to the wave pool 2. It is used to guide the oscillating water column 8 to the wave pool 2 to generate waves, extend the effective length of the oscillating water column 8, and adjust the guiding length of the oscillating water column 8 by adjusting the length of the horizontal section, thereby widening the resonant frequency adaptation range. By extending the effective length of the oscillating water column 8 and the terrain structure set inside the wave pool 2 to adapt to the nonlinear wave generation, the resonance of the oscillating water column 8 is realized, and the unique terrain structure provides a basis for wave morphology optimization.

[0041] It is worth noting that the electrical control subsystem 3 also includes a function for generating a length adjustment signal based on the target resonance period and transmitting it to the resonance subsystem; The resonant subsystem is used to adjust the length of the horizontal segment according to the length adjustment signal.

[0042] The variable frequency blower 4 continuously outputs compressed gas to the static pressure chamber 5 according to preset working parameters. When the pressure in the static pressure chamber 5 meets the preset pressure, the pressure relief valve 11 is opened to inject compressed gas into the air chamber 6 to enter the compressed air wave generation stroke. The pressure in the air chamber 6 increases, pushing the water level of the oscillating water column 8 to drop. The squeezed oscillating water column 8 flows into the wave pool 2 through the back bend pipe 9. Under the action of the topography of the wave pool 2, wave crests are formed. When the water pressure duration reaches the preset time, the exhaust valve 14 is opened to exhaust gas to the outside atmosphere, reducing the pressure in the air chamber 6 to atmospheric pressure. At this time, the water level rises to form wave troughs, realizing the stable generation of nonlinear waves of a given period. During this period, the oscillating water column 8 is guided through the back bend pipe 9 and the wave pool 2, which significantly extends the length of the oscillating water column 8 compared to the traditional straight pipe device, thereby effectively increasing the natural period of the wave generation system and reducing its natural frequency.

[0043] In this embodiment, as Figure 2 As shown, the resonant subsystem also includes: a back bend actuator 17, a tailpipe guide plate 18, a rigid baffle plate 19, and a tailpipe actuator 20. The back-bend actuator 17 is arranged on the top surface of the horizontal section of the back-bend 9. One end of the back-bend actuator 17 is fixed to the top surface of the curved part extending from the bottom of the cavity 7 away from the static air chamber 5 towards the wave pool 2, and the other end is fixedly connected to the vertical rigid baffle 19. The bottom surface of the back-bend actuator 17 is provided with a telescopic baffle 21 as the top surface of the horizontal section of the back-bend 9. The back-bend actuator 17 is used to adjust the length of the telescopic baffle 21 according to the length adjustment signal to realize the adjustment of the horizontal section length. The bottom of the horizontal section of the back bend 9 away from the cavity is movably connected to the tailpipe guide plate 18. The tailpipe guide plate 18 and the rigid baffle plate 19 form a curved guide tailpipe structure 22. The back bend 9 is connected to the wave pool 2 through the guide tailpipe structure 22 at the end, and is used to guide the oscillating water column 8 to the wave pool 2 to realize wave generation. One end of the tailpipe actuator 20 is fixed to the bottom structure of the wave pool 2 facing the tailpipe guide plate 18, and the other end is fixed to the plane of the tailpipe guide plate 18 facing the bottom structure. It is used to move the tailpipe guide plate 18 synchronously when the back bend actuator 17 moves, so as to keep the geometric dimensions of the guide tailpipe structure 22 unchanged.

[0044] In this embodiment, the back-bend actuator 17 is composed of a servo motor and a lead screw or hydraulic cylinder to achieve linear drive control, and then achieves the matching of the resonant oscillation water column length required for the target resonant period of different wave patterns by adjusting the length of the horizontal section.

[0045] It is worth noting that the rigid water barrier 19 can be made of thick stainless steel plate, galvanized steel plate or reinforced concrete plate with anti-corrosion coating. During the wave generation process, the rigid water barrier 19 can swing under the drive of the horizontal section with adjustable length to achieve further fine control of the wave pattern of the generated artificial wave and to provide some wave energy input.

[0046] As a preferred embodiment, the bottom of the horizontal section of the back bend 9 away from the cavity and the movable connection point of the tailpipe guide plate 18 is a variable bottom plate. The variable bottom plate and the concrete part of the bottom of the wave pool 2 are connected in a watertight manner using a flexible material or a rigid sliding baffle plate to adapt to the adjustable length of the horizontal section of the back bend 9 and form an additional vertical guide tube.

[0047] The working principle of the wave-generating unit excluding the U-tube is as follows: Under the unified timing control of the electrical control subsystem 3, the variable frequency blower 4 continuously outputs compressed gas according to preset parameters. This compressed gas is then delivered into the air chamber 6 via the gas pipeline 10 and the pressure relief valve 11. The increased gas pressure in the air chamber 6 pushes down the water level, causing the water to flow towards the wave pool 2 through the back bend, forming wave crests; this process is the pressurized water stroke. During the pressurized water stroke, the pressure limiting thresholds and activation ratios of each pressure limiting valve can be dynamically adjusted based on the measured timing results of each pressure sensor, thereby preventing system surge and reducing energy waste. After completing the wave-making compression stroke, the exhaust valve opens, and the air chamber 6 quickly connects to the outside atmosphere, entering the exhaust stroke. At this time, the internal pressure returns to atmospheric pressure, and the water on the wave pool 2 side flows back through the back bend, causing the water level in the air chamber 6 to rise and forming wave troughs within the wave pool 2. Through the periodic start-stop and pressure regulation of the variable frequency blower 4 and each valve, the continuous alternation of wave crests and troughs is achieved, generating stable artificial waves. In this system, the compressed air pressure from the blower, gravitational acceleration, the oscillating water column connected to the water tank, the exhaust valve 14 and the second pressure limiting valve 16 located in the air chamber 6, and the generated waves propagating in the water tank together constitute a nonlinear damped oscillation system with a complete nonlinear excitation force-restoring force-mass block-damping effect. Specifically, the compressed air pressure from the variable frequency blower 4 serves as the external nonlinear excitation force, gravity is the main restoring force, the oscillating water column 8 represents the mass block, the viscous loss of the exhaust valve 14 and each pressure limiting valve with the fluid constitutes the dissipative damping force, and the waves generated by the wave-generating system and propagating into the wave pool 2 constitute the radiation damping force. By adjusting the average oscillating mass of the oscillating water column 8, the natural frequency of this nonlinear damped oscillation system can be effectively adjusted. Matching this frequency with the target wave frequency (period) forms a highly efficient resonance system, maximizing wave generation efficiency and effectively reducing the cost per kilowatt-hour for each wave. This invention, by setting an adjustable-length horizontal section and its matching actuation system, directly connects to the vertical oscillating water column pipe of a traditional pneumatic wave generator, directly increasing the total length of the oscillating water column guide pipe, thereby dynamically improving the quality of the oscillating water column and controlling the natural frequency of the pneumatic wave generator system, achieves more efficient resonant wave generation than existing artificial wave generation technologies.

[0048] In some preferred embodiments, such as Figure 3 As shown, the resonant subsystem also includes: a back-bend actuator 17, a U-shaped tube 23, and a tailpipe actuator 20; One end of the back-bend actuator 17 is fixed to the top surface of the curved section extending from the bottom of the cavity 7 away from the static air chamber 5 toward the wave pool 2, and the other end extends or shortens toward the wave pool 2. The bottom surface of the back-bend actuator 17 is provided with a retractable baffle 21 as the top surface of the horizontal section of the back-bend 9. The back-bend actuator 17 is used to adjust the length of the retractable baffle 21 according to the length adjustment signal to realize the horizontal section length adjustment. The bottom of the horizontal section of the back bend 9 away from the cavity 7 is movably connected to the U-shaped tube 23. The U-shaped tube 23 is recessed toward the back bend actuator 17. The U-shaped tube 23 and the back bend actuator 17 form a curved guide tail pipe structure 22. The back bend 9 is connected to the wave pool 2 through the guide tail pipe structure 22 at its end, and is used to guide the oscillating water column 8 to the wave pool 2 to generate waves. One end of the tailpipe actuator 20 is fixed to the side of the bottom structure of the wave pool 2 facing the U-shaped tube 23, and the other end is fixed to the side of the U-shaped tube 23 facing the bottom structure. It is used to move the U-shaped tube 23 synchronously when the back bend actuator 17 moves, so as to keep the geometric dimensions of the guide tailpipe structure 22 unchanged.

[0049] The bottom of the horizontal section of the back bend 9, away from the cavity 7, is connected to the movable part of the U-shaped tube 23 by a variable bottom plate. The variable bottom plate is connected to the concrete part of the bottom of the wave pool 2 by a flexible material or a rigid sliding baffle plate in a watertight manner to adapt to the adjustable length of the horizontal section of the back bend 9 and form an additional vertical guide tube, which further extends the effective length of the oscillating water column 8 and improves the effect of the number of resonance modes and the range of the oscillating water column 8.

[0050] In the wave-generating unit including the U-shaped tube, the U-shaped tube 23 connects to the back bend tube 9 to form an extended oscillating water column channel. The wave pool 2 is equipped with a terrain structure adapted to nonlinear waves. The variable frequency blower 4 continuously outputs compressed gas according to preset parameters. The compressed gas is injected into the air chamber 6 through the gas supply pipe 10 and the pressure relief valve 11. The pressure in the air chamber 6 increases, pushing the water level down. To ensure that the operating pressure of the variable frequency blower does not exceed the stall threshold, when the pressure approaches the stall threshold, each pressure relief valve starts to vent, limiting the pressure in the air chamber 6. The water squeezed out by the pressure in the air chamber 6 flows into the wave pool 2 through the back bend tube 9 and the U-shaped tube 23, forming nonlinear wave crests under the guidance of the terrain. When the duration of water pressure in the air chamber 6 reaches the preset threshold, the variable frequency blower 4 stops supplying gas, the vent valve 14 opens, the pressure in the air chamber 6 drops to atmospheric pressure, the water level rises to form wave troughs, and stable long-period nonlinear waves are continuously generated alternately.

[0051] It is worth noting that artificial surfing pools equipped with this resonant nonlinear wave-generating system can be used in sports venues to generate waves to meet the needs of surfing competitions.

[0052] like Figure 4 As shown, this embodiment provides a design method for the above-mentioned resonant nonlinear wave generation system for artificial surfing pools, including determining the adjustment length of the horizontal section of the back bend 9 according to the target resonance period: Step 1: Obtain the target resonance period and the initial values ​​of the free liquid surface area, vertical cross-sectional area, horizontal cross-sectional area, total length of vertical section, and total length of horizontal section of the oscillating water column 8 in the gas chamber 6; Step 2: Based on the initial values ​​of the free surface area, vertical cross-sectional area, horizontal cross-sectional area, total length of vertical section, and total length of horizontal section of the oscillating water column 8, perform fluid dynamics numerical simulation under different water depth conditions to obtain the actual resonance period range. Step 3: Divide the upper and lower bounds of the actual resonance period by the target resonance period to obtain the upper and lower bounds of the resonance period variation coefficient; based on the determined K value, algebraic calculations can be performed to determine the corrected water column resonance geometric parameter values. , , , Based on actual layout constraints and construction conditions, the design of the wave-generating air chamber unit is carried out using either a backward-curved tube or a U-shaped tube configuration.

[0053] Step 4: Based on the upper and lower bounds of the resonance period variation coefficient, the free liquid surface area, vertical cross-sectional area, horizontal cross-sectional area, and total vertical length of the oscillating water column 8, and the target resonance period, calculate the actual range of the total horizontal length of the oscillating water column 8 when resonance is achieved. The back bend 9, together with the variable frequency blower 4 and various electrically controlled valves, constitute an oscillating water column system. This system possesses a specific resonant frequency, and the specific power frequency corresponds to a specific resonant period. The air chamber operating under resonant period conditions can achieve maximum wave-generating efficiency, thereby significantly reducing energy consumption. Under ideal conditions, the resonant period of the back bend is calculated as follows: ; in, Indicates the target resonance period. This represents the coefficient of variation of the resonance period. The free surface area of ​​the oscillating water column, Indicates the cross-sectional area of ​​the vertical portion of the oscillating water column, Indicates the cross-sectional area of ​​the horizontal portion of the oscillating water column, Indicates the total length of the vertical portion of the oscillating water column. This represents the initial value of the total length of the horizontal portion of the oscillating water column. This represents gravitational acceleration. The target resonance period should, in principle, match the actual wave cycle in the ocean (approximately 6s-30s), and be determined comprehensively considering the wave pool's construction cost, logistical requirements, and operational needs. Based on this formula, and combined with the wave pool's actual configuration, maximum water depth, and facility height restrictions, the actual total length of the horizontal portion of the oscillating water column at resonance is determined.

[0054] Step 5: Subtract the initial value of the total length of the horizontal section from the actual value range of the total length of the horizontal section to obtain the adjustment length range of the horizontal section of the back bend. Based on the adjustment length range, adjust the initial value of the total length of the horizontal section of the oscillating water column 8 to the actual value range of the total length of the horizontal section to achieve resonance of the oscillating water column 8 under different water depth conditions.

[0055] For the horizontal section of the adjustable-length backbend pipe, the adjustment length is: Therefore, the natural frequency of the system can be controlled by adjusting its length, and the control range can be expressed by the following formula: ; In actual engineering design practice, appropriate selection should be made based on the target application requirements of the artificial wave pool project. The value of is determined to achieve precise matching of the target wave pattern resonance cycle.

[0056] Through structural innovation and terrain-coordinated design, the length, cross-sectional area, and volume of the oscillating water column can be flexibly adjusted under the constraints of pit depth and maximum water depth. This enables precise resonance matching between the oscillating water column and artificial high-quality surfable waves, stably generating long-period nonlinear waves that meet the needs of professional surfing, significantly reducing energy loss and operating costs, and creating a professional and efficient artificial wave-making venue for surfing enthusiasts.

[0057] The resonant nonlinear wave generation system and its design method provided in this embodiment have the following beneficial effects: By adjusting the length of the horizontal section to regulate the average oscillating mass of the oscillating water column 8, the natural frequency of the nonlinear damped oscillation system can be effectively adjusted. Matching this to the target wave frequency (period) forms a highly efficient resonance system, maximizing wave generation efficiency and effectively reducing the power cost per wave. This invention, by setting an adjustable-length horizontal section and its associated actuation system, directly connects it to the vertical oscillating water column pipe of a traditional pneumatic wave generator, directly increasing the total length of the oscillating water column guide pipe, thereby dynamically improving the mass of the oscillating water column and controlling the natural frequency of the pneumatic wave generator system. This achieves more efficient resonant wave generation compared to existing artificial wave generation technologies.

[0058] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0059] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A resonant nonlinear wave generation system for artificial surfing pools, characterized in that, include: Several wave-making units (1) are arranged along the preset axis of the wave pool (2). When making waves, each wave-making unit (1) is triggered in sequence according to a preset time sequence to generate waves of several different wave types. Any of the wave-generating units (1) includes: an electrical control subsystem (3), a variable frequency blower (4), a static pressure chamber (5), an air chamber (6), and a resonance subsystem; The electrical control subsystem (3) is used to control the variable frequency blower (4) to continuously output compressed gas to the static pressure chamber (5), and to control the injection of compressed gas in the static pressure chamber (5) into the gas chamber (6). The air chamber (6) is formed by the cavity (7) and the top surface of the oscillating water column (8), and is used to continuously squeeze the oscillating water column (8) according to the internal pressure until the water pressure time reaches the preset time. The resonant subsystem includes a back bend (9) that bends towards the water surface at the end, is horizontal in the middle, and has an adjustable horizontal section length. The first end of the back bend (9) is connected to the bottom of the cavity (7), and the last end is connected to the wave pool (2). It is used to guide the oscillating water column (8) to the wave pool (2) to generate waves, and to adjust the guiding length of the oscillating water column (8) by adjusting the horizontal section length to achieve resonance of the oscillating water column (8).

2. The resonant nonlinear wave generation system according to claim 1, characterized in that, The electrical control subsystem (3) also includes a real-time variable frequency adjustment signal for generating working parameters based on the obtained speed of the variable frequency blower (4), the pressure of the static pressure chamber (5), the pressure of the air chamber (6) and the preset target working pressure, and transmitting it to the variable frequency blower (4). The variable frequency blower (4) is connected to the electrical control subsystem (3) and is connected to the air inlet of the static pressure chamber (5) through the gas pipeline (10). The variable frequency blower (4) is used to adjust the working parameters according to the real-time variable frequency adjustment signal and continuously output compressed gas to the static pressure chamber (5).

3. The resonant nonlinear wave generation system according to claim 2, characterized in that, The electrical control subsystem (3) also includes a pressure relief valve (11) for generating a pressure relief signal and transmitting it to the static pressure chamber (5) when the pressure in the static pressure chamber (5) reaches a preset pressure. The static pressure chamber (5) is connected to the gas chamber (6) through the pressure relief valve (11), which is used to open the pressure relief valve (11) according to the pressure relief signal to inject compressed gas into the gas chamber (6).

4. The resonant nonlinear wave generation system according to claim 3, characterized in that, It also includes a sensor subsystem, which includes: a static pressure chamber pressure sensor (12) arranged in the static pressure chamber (5) and a gas chamber pressure sensor (13) arranged in the gas chamber (6). The static pressure chamber pressure sensor (12) is electrically connected to the electrical control subsystem (3) and is used to monitor the pressure of the static pressure chamber (5) in real time and transmit it to the electrical control subsystem (3). The air chamber pressure sensor (13) is electrically connected to the electrical control subsystem (3) and is used to monitor the pressure of the air chamber (6) in real time and transmit it to the electrical control subsystem (3).

5. The resonant nonlinear wave generation system according to claim 1, characterized in that, The electrical control subsystem (3) also includes an exhaust valve (14) for generating an exhaust signal and transmitting it to the air chamber (6) when the water pressure duration reaches the preset water pressure stroke duration. The air chamber (6) is connected to the outside atmosphere through the exhaust valve (14), which is used to open the valve to exhaust air according to the exhaust signal.

6. The resonant nonlinear wave generation system according to claim 1, characterized in that, The static pressure chamber (5) is provided with a first pressure limiting valve (15), and the static pressure chamber (5) is connected to the outside atmosphere through the first pressure limiting valve (15); the air chamber (6) is provided with a second pressure limiting valve (16), and the air chamber (6) is connected to the outside atmosphere through the second pressure limiting valve (16); the first pressure limiting valve (15) and the second pressure limiting valve (16) are both electrically connected to the electrical control subsystem (3), and the electrical control subsystem (3) further includes a function to control the first pressure limiting valve (15) and / or the second pressure limiting valve to exhaust (16) when the working pressure of the variable frequency blower (4) reaches 90%-98% of the preset stall threshold.

7. The resonant nonlinear wave generation system according to claim 1, characterized in that, The electrical control subsystem (3) also includes a length adjustment signal generated according to the target resonance period and transmitted to the resonance subsystem; The resonant subsystem is used to adjust the length of the horizontal segment according to the length adjustment signal.

8. The resonant nonlinear wave generation system according to claim 7, characterized in that, The resonant subsystem also includes: a back bend actuator (17), a tailpipe guide plate (18), a rigid baffle plate (19), and a tailpipe actuator (20). The back-bend actuator (17) is arranged on the top surface of the horizontal section of the back-bend (9), and one end of the back-bend actuator (17) is fixed to the top surface of the curved part extending from the bottom of the cavity (7) away from the static air chamber (5) towards the wave pool (2), and the other end is fixedly connected to the rigid baffle (19). The bottom surface of the back-bend actuator (17) is provided with a telescopic baffle (21) as the top surface of the horizontal section of the back-bend (9). The back-bend actuator (17) is used to adjust the length of the telescopic baffle (21) according to the length adjustment signal to realize the adjustment of the horizontal section length. The bottom of the horizontal section of the back bend (9) away from the cavity (7) is movably connected to the tailpipe guide plate (18). The tailpipe guide plate (18) and the rigid baffle plate (19) form a curved guide tailpipe structure (22). The back bend (9) is connected to the wave pool (2) through the guide tailpipe structure (22) at the end, and is used to guide the oscillating water column (8) to the wave pool (2) to realize wave generation. One end of the tailpipe actuator (20) is fixed to the bottom structure of the wave pool (2) facing the tailpipe guide plate (18), and the other end is fixed to the plane of the tailpipe guide plate (18) facing the bottom structure. It is used to move the tailpipe guide plate (18) synchronously when the back bend actuator (17) moves, so as to keep the geometric dimensions of the guide tailpipe structure (22) unchanged.

9. The resonant nonlinear wave generation system according to claim 7, characterized in that, The resonant subsystem also includes: a back-bend actuator (17), a U-tube (23), and a tailpipe actuator (20). One end of the back bend actuator (17) is fixed to the top surface of the bend extending from the bottom of the cavity (7) away from the static air chamber (5) toward the wave pool (2), and the other end extends or shortens toward the wave pool (2). A retractable baffle (21) is arranged on the bottom surface of the back bend actuator (17) as the top surface of the horizontal section of the back bend (9). The back bend actuator (17) is used to adjust the length of the retractable baffle (21) according to the length adjustment signal to realize the horizontal section length adjustment. The bottom of the horizontal section of the back bend (9) away from the cavity (7) is movably connected to the U-shaped tube (23). The U-shaped tube (23) is recessed toward the back bend actuator (17). The U-shaped tube (23) and the back bend actuator (17) form a curved guide tail pipe structure (22). The back bend (9) is connected to the wave pool (2) through the guide tail pipe structure (22) at the end, and is used to guide the oscillating water column (8) to the wave pool (2) to realize wave generation. One end of the tailpipe actuator (20) is fixed to the bottom structure of the wave pool (2) facing the U-shaped tube (23), and the other end is fixed to the U-shaped tube (23) facing the bottom structure. It is used to move the U-shaped tube (23) synchronously when the back bend actuator (17) moves, so as to keep the geometric dimensions of the guide tailpipe structure (22) unchanged.

10. A design method for a resonant nonlinear wave-generating system for an artificial surfing pool as described in claim 7, characterized in that, This includes determining the adjustment length of the horizontal section of the back bend (9) based on the target resonance period: Step 1: Obtain the target resonance period and the initial values ​​of the free liquid surface area, vertical cross-sectional area, horizontal cross-sectional area, total length of vertical part, and total length of horizontal part of the oscillating water column (8) in the gas chamber (6); Step 2: Based on the initial values ​​of the free liquid surface area, vertical cross-sectional area, horizontal cross-sectional area, vertical total length, and horizontal total length of the oscillating water column (8) under different water depth conditions, perform fluid dynamics numerical simulation to obtain the actual resonance period range; Step 3: Divide the upper and lower bounds of the actual resonance period by the target resonance period to obtain the upper and lower bounds of the resonance period variation coefficient; Step 4: Based on the upper and lower bounds of the resonance period variation coefficient, the free liquid surface area, vertical cross-sectional area, horizontal cross-sectional area, and total vertical length of the oscillating water column (8), and the target resonance period, calculate the actual range of the total horizontal length of the oscillating water column (8) when resonance is achieved. Step 5: Subtract the initial value of the total length of the horizontal section from the actual value range of the total length of the horizontal section to obtain the adjustment length range of the horizontal section of the back bend. Based on the adjustment length range, adjust the initial value of the total length of the horizontal section of the oscillating water column (8) to the actual value range of the total length of the horizontal section to achieve resonance of the oscillating water column (8) under different water depth conditions.

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