Method and system for designing three-section combined structure of ultrahigh wind power generation tower drum

Abstract

The invention relates to the technical field of data processing, and discloses a three-section combined structure design method and system for an ultrahigh wind power generation tower. The method comprises the following steps: analyzing wind speed distribution data through a wind load-structural dynamics-material mechanics coupling algorithm to obtain rigidity distribution functions and frequency avoidance constraints of three functional partitions, performing multi-objective optimization on a lower truss section to obtain geometric parameter configuration, performing fluid-solid coupling vibration control design on a middle multi-edge transition section, and performing multi-functional partition design on the middle multi-edge transition section. And aeroelastic instability prevention and control design is carried out on the upper cylindrical section, integrated dynamic coordination processing is carried out on the three-section structure, multi-working-condition verification is carried out through a large eddy simulation-finite element coupling verification algorithm, and target design parameters are obtained. The wind power tower drum solves the technical problems that the existing wind power tower drum technology cannot break through the limitation of the 360-meter super height and cannot meet the requirements of structural safety, economical efficiency and constructability at the same time.

Description

Technical Field

[0001] The present application relates to the field of data processing technology, and in particular to a design method and system for a three-section combined structure of an ultra-high wind power tower. Background Art

[0002] In the existing wind power generation technology, with the acceleration of the transformation of the global energy structure, wind turbines are developing towards high power and high altitude. The capacity of offshore wind turbines is rapidly iterating from 8-20MW to 30-50MW, and the land wind tower is transforming from 5MW to 30MW. In order to obtain high-quality wind resources at an altitude of 60-700 meters, mainstream wind farms have required the tower height to be increased from the current 120-160 meters to 190 meters, and is developing towards more than 360 meters to ensure the safe operation of the blades in the high-quality wind section. The existing wind power tower technology mainly adopts structural forms such as steel-concrete composite towers, traditional cylindrical steel towers and truss towers.

[0003] However, the existing wind turbine tower technology has significant structural defects, high costs, transportation restrictions and other problems. The concrete and steel connection interface of the steel-concrete composite tower is prone to microcracks and has poor dynamic performance, with resonance risks and collapse risks. Traditional cylindrical steel towers are difficult to transport on roads. In order to meet the stiffness requirements, the wall thickness of the steel plate in the bottom section reaches 60-90mm, resulting in a large amount of material waste. When the upper and middle sections of the truss tower are too high, the lack of anti-sway, anti-bending and anti-seismic performance becomes a bottleneck.

[0004] Based on the analysis of the limitations of existing technologies, when the tower height exceeds 300 meters and develops towards 360 meters, the traditional single structural form cannot simultaneously solve the contradiction between high-strength stiffness requirements, transportation convenience and vibration resistance. The existing technology lacks a multi-physics field coupling design method for ultra-high wind towers, and cannot systematically solve the problem of coordinated optimization of wind load-structural dynamics-material mechanics, resulting in technical bottlenecks such as the inability to avoid resonant frequency, excessive material consumption, high transportation costs, and long installation cycles at an ultra-high height of 360 meters. It is urgent to break through the traditional design concept and establish a systematic design method for ultra-high wind towers. Summary of the invention

[0005] The present application provides a method and system for designing a three-section combined structure of an ultra-high wind power tower, which is used to solve the technical problem that the existing wind power tower technology cannot break through the ultra-high height limit of 360 meters and at the same time meet the requirements of structural safety, economy and constructability.

[0006] In a first aspect, the present application provides a design method for a three - section combined structure of an ultra - high wind power generation tower barrel. The design method for the three - section combined structure of the ultra - high wind power generation tower barrel includes: performing a multi - physical - field collaborative analysis on the wind speed distribution data of a target wind farm through a wind load - structural dynamics - material mechanics coupling algorithm to obtain the stiffness distribution function and frequency avoidance constraints of the three functional partitions; performing multi - objective optimization on the geometric parameters of the lower truss section according to the stiffness distribution function to obtain the optimized configurations of the diagonal bracing crossing angle, the main diagonal tube specifications, and the steel wire rope - concrete composite section; using the dynamic characteristics of the lower truss section as boundary conditions to perform fluid - structure interaction vibration control design on the middle multi - prism transition section to obtain the geometric parameters of the 12 - sided multi - prism, the TMD device parameters, and the layout scheme of 24 viscous dampers; based on the vibration control results of the middle multi - prism transition section, performing aero - elastic instability prevention and control design on the upper cylindrical section to obtain the number distribution of multiple cylindrical structures, the trapezoidal longitudinal rib configuration, and the layered pre - tension distribution; performing an integrated dynamic coordination process on the dynamic characteristics of the three sections to obtain the full - tower frequency avoidance matrix and the impedance matching parameters for the inter - section connection; and performing multi - condition coupling verification on the three - section combined structure design scheme through a large - eddy simulation - finite - element coupling verification algorithm to obtain the target design parameters.

[0007] In a second aspect, the present application provides a design system for a three - section combined structure of an ultra - high wind power generation tower barrel. The design system for the three - section combined structure of the ultra - high wind power generation tower barrel includes: An analysis module, configured to perform a multi - physical - field collaborative analysis on the wind speed distribution data of a target wind farm through a wind load - structural dynamics - material mechanics coupling algorithm to obtain the stiffness distribution function and frequency avoidance constraints of the three functional partitions; An optimization module, configured to perform multi - objective optimization on the geometric parameters of the lower truss section according to the stiffness distribution function to obtain the optimized configurations of the diagonal bracing crossing angle, the main diagonal tube specifications, and the steel wire rope - concrete composite section; A control module, configured to use the dynamic characteristics of the lower truss section as boundary conditions to perform fluid - structure interaction vibration control design on the middle multi - prism transition section to obtain the geometric parameters of the 12 - sided multi - prism, the TMD device parameters, and the layout scheme of 24 viscous dampers; A design module, configured to perform aero - elastic instability prevention and control design on the upper cylindrical section based on the vibration control results of the middle multi - prism transition section to obtain the number distribution of multiple cylindrical structures, the trapezoidal longitudinal rib configuration, and the layered pre - tension distribution; A coordination module, configured to perform an integrated dynamic coordination process on the dynamic characteristics of the three sections to obtain the full - tower frequency avoidance matrix and the impedance matching parameters for the inter - section connection; A verification module, configured to perform multi - condition coupling verification on the three - section combined structure design scheme through a large - eddy simulation - finite - element coupling verification algorithm to obtain the target design parameters.

[0008] In the technical solution provided by this application, a multi-physical field collaborative analysis method established through a wind load - structural dynamics - material mechanics coupling algorithm breaks through the limitations of independent analysis of a single physical field in the prior art. By simultaneously considering the interaction between wind load and structural deformation, and the coupling relationship between structural dynamics response and material mechanics constraints, this coupling algorithm realizes the systematic optimization design of a 360-meter super-high wind tower, effectively solving the resonance risk, material waste, and collapse hidden danger that occur above 185 meters in traditional wind towers. The multi-objective optimization processing method based on the stiffness distribution function realizes the accurate solution of the geometric parameters of the lower truss section by establishing a comprehensive objective function of weight minimization, stress control, displacement limitation, and frequency requirements. The design of the diagonal bracing crossing angle of 50 degrees plus or minus 5 degrees minimizes the wind resistance coefficient. The optimized configuration of the steel wire rope - concrete composite section increases the equivalent stiffness by 35% compared with the traditional pure steel structure while only increasing the weight by 12%. The fluid-structure interaction vibration control design establishes a vortex shedding suppression mechanism for a 12-sided polyhedron, combined with the optimization layout of TMD device parameters and 24 viscous dampers, to increase the structural damping ratio from the traditional 0.5% to 2.8%, effectively solving the wind-induced vibration problem in the middle transition section. The aeroelastic instability prevention and control design determines the distribution of the number of multi-piece cylindrical structures through Reynolds number correlation optimization, combined with the trapezoidal longitudinal rib configuration and hierarchical pre-tension distribution, to increase the critical aeroelastic instability wind speed of the upper cylindrical section from 45 m / s to 65 m / s. The integrated dynamic coordination processing establishes a full-tower frequency avoidance matrix and impedance matching parameters for inter-segment connections to ensure that the first three natural frequencies of 0.12 Hz, 0.31 Hz, and 0.58 Hz all avoid the impeller passing frequency of 0.15 - 0.2 Hz and its multiples, eliminating the resonance risk.

[0009] The large eddy simulation - finite element coupling verification algorithm verifies the design scheme by establishing a large-scale coupling verification matrix and using the time-domain fluid-structure interaction calculation method to ensure that key safety indicators such as the maximum displacement, maximum stress, and fatigue damage degree all meet the design requirements, verifying the feasibility of the ultra-high wind turbine tower design. The comprehensive technical effects of the present invention are reflected in: a significant reduction in steel consumption, resulting in a significant weight reduction; a substantial savings in the transportation cost of a single-stage tower; a significant shortening of the installation period; a substantial reduction in the annual resonance shutdown loss; a significant increase in power generation revenue. At the same time, the use of weather-resistant composite steel plates enables long-term maintenance-free operation, the one-time hot rolling technology of wedge plates effectively saves materials, the seamless welding and internal rib stiffening plates reduce stress concentration, and the modular flange is thickened and designed with high-strength prestressed bolts and multiple shear keys to ensure connection reliability. Description of the Drawings

[0010] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0011] Figure 1 This is a schematic diagram of an embodiment of the design method for the three-section combined structure of an ultra-high wind power generation tower barrel in an embodiment of the present application; Figure 2 This is a schematic diagram of an embodiment of the design system for the three-section combined structure of an ultra-high wind power generation tower barrel in an embodiment of the present application. Detailed implementation manners

[0012] The embodiments of the present application provide a design method and system for the three-section combined structure of an ultra-high wind power generation tower barrel. Terms such as "first", "second", "third", "fourth", etc. (if any) in the specification, claims, and above-mentioned drawings of the present application are used to distinguish similar objects, and do not have to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments described here can be implemented in an order other than that illustrated or described here. In addition, the terms "comprising" or "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0013] For ease of understanding, the following describes the specific process of the embodiments of the present application. Please refer to Figure 1 , an embodiment of the design method for the three-section combined structure of an ultra-high wind power generation tower barrel in an embodiment of the present application includes: Step S101: Perform multi-physical field collaborative analysis on the wind speed distribution data of the target wind farm through the wind load - structural dynamics - material mechanics coupling algorithm to obtain the stiffness distribution function of the three functional partitions and the frequency avoidance constraint; Step S102: Perform multi-objective optimization processing on the geometric parameters of the lower truss section according to the stiffness distribution function to obtain the optimized configuration of the diagonal bracing crossing angle, the main diagonal tube specification, and the steel wire rope - concrete composite section; Step S103: Use the dynamic characteristics of the lower truss section as boundary conditions to perform fluid-structure interaction vibration control design on the middle multi-faceted transition section to obtain the geometric parameters of the 12-sided polyhedron, the parameters of the TMD device, and the layout scheme of 24 viscous dampers; Step S104: Based on the vibration control results of the middle multi-faceted transition section, conduct aeroelastic instability prevention and control design for the upper cylindrical section to obtain the number distribution of multiple cylindrical structures, the configuration of trapezoidal longitudinal ribs, and the layered pre-tension distribution. Step S105: Conduct integrated dynamic coordination processing on the dynamic characteristics of the three-section structure to obtain the full-tower frequency avoidance matrix and the impedance matching parameters for the inter-section connection. Step S106: Conduct multi-condition coupling verification on the design scheme of the three-section combined structure through the large eddy simulation - finite element coupling verification algorithm to obtain the target design parameters.

[0014] It can be understood that the execution subject of this application can be a three-section combined structure design system for ultra-high wind power generation tower barrels, or it can also be a terminal or a server, and specific limitations are not made here. In this embodiment of the application, the server is used as the execution subject for illustration.

[0015] Specifically, collect real-time wind speed distribution data in the height range of 60 meters to 700 meters from the target wind farm. The data includes parameters such as wind speed values, wind direction angles, and turbulence intensities at different heights. The wind speed gradient function corrects the original wind speed data according to the surface roughness index to calculate the accurate wind load values for each height section. Then, input the wind load distribution characteristics into the structural dynamics model, which considers the mass distribution, damping characteristics, and stiffness changes of the tower barrel, and obtains the displacement response and stress distribution data for each height section by solving the motion equation. When constructing the stiffness distribution function based on the displacement response data, the system analyzes the characteristics that the 0 - 120-meter section needs to bear the maximum wind load and gravity load, and designs it as a high-stiffness section; the 120 - 200-meter section is used as a mechanical property transition area, and the stiffness decreases in a gradient; the 200 - 360-meter section has relatively small wind loads and is designed as a lightweight low-stiffness section. During the establishment of the frequency avoidance constraint, the system extracts the impeller passing frequency of 0.15 - 0.2 Hz as the reference frequency, and generates the avoidance matrix for the first three natural frequencies through mathematical operations to ensure that the natural frequencies of the tower barrel are staggered from the impeller excitation frequency and avoid resonance.

[0016] The stiffness distribution function is input into the optimization model as a constraint condition. This model simultaneously considers four objectives: weight minimization, stress control, displacement limitation, and frequency requirements. Through iterative calculations, it determines the main diagonal tube diameter range of 500 - 1500 mm, wall thickness range of 8 - 16 mm, diagonal bracing angle range of 45 - 55 degrees, and chord diameter range of 20 - 30 mm. During the calculation of minimizing the wind resistance coefficient, the system establishes a relationship function between the diagonal bracing angle and the wind resistance coefficient. Through numerical analysis, it is found that the wind resistance coefficient reaches the minimum value at a diagonal bracing crossing angle of 50 degrees, forming an optimal force transmission path. The optimized design of the wire rope pre-tension is based on the principle of maximizing the equivalent stiffness of the composite section. It calculates the stiffness contributions of the wire rope, steel pipe, and concrete, and determines the pre-tension value and wire rope specification parameters. Finally, the optimized main diagonal tube specifications, diagonal bracing crossing angle, and wire rope parameters are input into the C50 concrete casting process to form a steel pipe - wire rope - concrete composite load-bearing system.

[0017] The dynamic characteristics of the lower truss section are used as boundary conditions and input into the fluid-structure interaction control model for the design of the middle transition section. This model uses computational fluid dynamics methods to analyze the flow field characteristics around a 12-sided polyhedron, and calculates the Strouhal number and the corresponding vortex shedding frequency. Based on the vortex shedding frequency data, the geometric shape of the polyhedron is rounded at the edges and corners. By changing the edge curvature radius, the vortex shedding intensity is reduced, and the amplitude of wind-induced vibration is decreased. During the parameter design of the TMD device, the system calculates the mass ratio of 0.02, frequency ratio of 0.95, and damping ratio of 0.1 of the TMD system according to the geometric parameters of the polyhedron, ensuring an optimal tuning relationship between the TMD device and the main frequency of the structure. The layout optimization of 24 viscous dampers uses a position iteration algorithm, taking the TMD device parameters as constraint conditions, and calculates the optimal installation position, damping coefficient of 2000 kN·s / m, and velocity exponent of 0.3 for each damper to form a vibration control layout scheme.

[0018] Based on the results of vibration control, the aeroelastic instability prevention and control design of the upper cylindrical section is carried out. The system inputs the vibration control data of the middle transition section into the aeroelastic stability discrimination model, and calculates key parameters such as the lift coefficient, drag coefficient and aerodynamic derivative through eigenvalue solution. The Reynolds number correlation method is used in the optimization process of the number of slices distribution. According to the wind speed conditions and structural requirements of different height sections, the distribution scheme of 18 slices for 200-280 meters, 12 slices for 280-320 meters, and 6 slices for 320-360 meters is determined. In the design of the trapezoidal longitudinal rib configuration, the system calculates the variation law of the rib height of 200-800 mm, the optimal value of the rib width ratio of 0.6 and the uniform arrangement of rib spacing of 600 mm, and verifies the design scheme through aerodynamic drag reduction analysis. The pre-tension optimization calculation inputs the trapezoidal longitudinal rib configuration into the geometric stiffness matrix, and obtains the pre-tension gradient distribution of 150 kN at the bottom layer, 120 kN at the middle layer, and 90 kN at the top layer. The layered layout design of the wire rope determines the spatial distribution mode of the first layer at 0 degrees, 120 degrees, and 240 degrees, and the second layer at 60 degrees, 180 degrees, and 300 degrees. The dynamic characteristics of the above three-segment structure are input into the segmented coupling dynamic model for integrated coordination. The model establishes the mass matrix, damping matrix, and stiffness matrix of the whole tower, reflecting the coupling characteristics of the three-segment structure. The coordinated calculation of the frequency ratio of adjacent segments ensures that the frequency ratio is controlled within the range of 0.7-1.3 to avoid local resonance. The modal vibration continuity constraint ensures smooth vibration transmission at the connection between segments to prevent stress concentration. In the process of establishing the frequency avoidance matrix of the whole tower, the system calculates the first three frequencies of 0.12Hz, 0.31Hz, and 0.58Hz to ensure that the impeller passing frequency and its multiples are avoided. The impedance matching optimization of the inter-segment connection is carried out by analyzing the vibration energy transfer, calculating the connection stiffness and damping parameters, and controlling the stress concentration factor to be less than 1.5. The overall design scheme is fully verified by the large eddy simulation-finite element coupling verification algorithm. The large eddy simulation numerical test platform establishes a three-dimensional calculation domain with a diameter of 15 times the windward direction, 30 times the leeward direction, and 10 times the lateral diameter, with a total number of grids exceeding 20 million to ensure the calculation accuracy. The multi-condition combination arranges and combines the wind speed of 3-25 meters per second, the turbulence intensity of 5%-25%, and the wind direction angle of 0-180 degrees to form a coupling verification matrix of 525 verification conditions. The fluid-solid coupling algorithm adopts the time domain solution method to calculate the interaction between the fluid and the structure in real time, and obtains key indicators such as maximum displacement, maximum stress and fatigue damage. The verification results show that the maximum displacement is less than 1 / 116 of the tower height, the maximum stress is less than 254 MPa, and the fatigue damage is less than 0.5, meeting the requirements of 360 meters super height and 25 years of design life.

[0019] It should be noted that in the present application, the middle polygonal transition section and the upper cylindrical section are mainly designed as keel reinforcement support points. The keel structure is a trapezoidal area with a clever combination of longitudinal flanges. An inner annular flange is installed every 4 meters in the middle polygonal transition section and the upper cylindrical section. The structure is adjustable by tightening the wire rope.

[0020] In a specific embodiment, the process of executing step S101 may specifically include the following steps: Obtain the wind speed distribution data within the height range of 60 meters to 700 meters of the target wind farm, calculate the wind load field through the wind speed gradient function, and obtain the wind load distribution characteristics of different height segments; Input the wind load distribution characteristics into the structural dynamics model for coupled solution to obtain the displacement response and stress distribution of each height segment; Based on the displacement response, construct the stiffness distribution function in a piecewise continuous manner to obtain the gradient distributions of the stiffness coefficients in the 0 - 120 meter segment, 120 - 200 meter segment, and 200 - 360 meter segment; Establish frequency avoidance constraints according to the impeller passing frequency of 0.15 - 0.2 Hz for resonance avoidance calculation to obtain the avoidance matrix of the first three natural frequencies and the safety frequency bandwidth parameters.

[0021] Specifically, obtaining the wind speed distribution data within the height range of 60 meters to 700 meters of the target wind farm is completed by a multi - layer wind speed sensor array. The sensors are arranged at a vertical interval of 20 meters to collect the instantaneous wind speed, average wind speed, and turbulence intensity data at each height point. The wind speed gradient function corrects the original wind speed data according to the exponential law. This function takes into account the influence of surface roughness on the wind speed, and calculates the wind speed value at any height by taking the exponential power of the height ratio of the reference height wind speed value, where the exponential value is determined according to the surface type. The wind load field calculation substitutes the corrected wind speed data into the wind pressure calculation formula, combines the air density, wind resistance coefficient, and windward area parameters, and calculates the wind load values of each height segment layer by layer to form a wind load distribution characteristic curve from the bottom to the top.

[0022] When inputting the wind load distribution characteristics into the structural dynamics model, the model discretizes the tower barrel into multiple node units, and each unit bears the wind load acting at the corresponding height. The structural dynamics model establishes a mass matrix to reflect the mass distribution of each segment, a damping matrix to reflect the material damping characteristics, and a stiffness matrix to reflect the structural stiffness change, and calculates the dynamic response of the structure under the action of the wind load by solving the motion equation. During the coupled solution process, the wind load and the structural deformation interact with each other. The structural deformation changes the windward area and thus affects the wind load magnitude, forming a coupled calculation cycle of wind - structure interaction. The displacement response calculation obtains the horizontal displacement, vertical displacement, and rotational displacement of each height node, and the stress distribution calculation obtains the distribution laws of the bending stress, axial stress, and shear stress of each cross - section.

[0023] When constructing the piecewise continuous stiffness distribution function based on the displacement response, the stiffness requirements are determined by analyzing the displacement gradient change law in each height segment. The small displacement response in the 0-120 m segment indicates that high stiffness support is needed, and the stiffness coefficient takes the maximum value as the reference stiffness. The displacement response in the 120-200 m segment shows an increasing trend, and the stiffness coefficient is distributed according to the linear decreasing law, and the decreasing amplitude is determined according to the displacement change rate. The displacement response in the 200-360 m segment is large but the load is relatively small, and the stiffness coefficient takes a smaller value to meet the lightweight requirement. The stiffness coefficients of the three segments are connected by a continuous function, and the stiffness value smoothly transitions at the segment joints to avoid stress concentration caused by stiffness mutation. The gradient distribution is numerically fitted to obtain the continuous function expression of the stiffness varying with height.

[0024] When establishing the frequency avoidance constraint according to the impeller passing frequency, first determine the passing frequency interval 0.15-0.2 Hz corresponding to the impeller speed range, and then calculate the first three natural frequencies of the tower structure. The resonance avoidance calculation makes the natural frequency avoid the impeller passing frequency and its multiples by adjusting the structural parameters. The specific method is to leave a safety frequency bandwidth of 0.02 Hz above and below the impeller passing frequency. The avoidance matrix of the first three frequencies arranges the natural frequency of the tower, the impeller passing frequency and its multiples in matrix form, and checks whether the difference between any two frequency values in the matrix meets the safety bandwidth requirement. The safety frequency bandwidth parameter is determined according to the structural damping ratio and the excitation amplitude. The smaller the damping ratio, the larger the required safety bandwidth.

[0025] In a specific embodiment, the process of executing step S102 may specifically include the following steps: Input the stiffness distribution function into the multi-objective optimization model to solve the geometric parameters of the truss, and obtain the main diagonal tube diameter range, wall thickness range, diagonal bracing angle range and chord diameter range; Based on the principle of minimizing the wind resistance coefficient, optimize and calculate the diagonal bracing angle range to obtain the diagonal bracing crossing angle of 50 degrees plus or minus 5 degrees and the corresponding wind resistance coefficient; Optimize the design of the wire rope pretension according to the goal of maximizing the equivalent stiffness of the composite section, and obtain the wire rope specification parameters and pretension values corresponding to the main diagonal tube specifications; Input the main diagonal tube diameter range, the diagonal bracing crossing angle and the wire rope specification parameters into the C50 concrete casting process to construct the composite section, and obtain the optimized configuration of the wire rope-concrete composite section.

[0026] Specifically, when the stiffness distribution function is input into the multi-objective optimization model, the optimization model establishes multiple objective functions including weight minimization, stress control, displacement constraints, and frequency matching, while setting strength constraints, geometric constraints, and manufacturing process constraints as boundary conditions. During the process of solving the geometric parameters of the truss, the model determines the stiffness requirements of each section according to the stiffness distribution function, and through iterative calculation, it determines that the diameter range of the main inclined tube is between 500 and 1500 millimeters. The lower bound of this range is restricted by the minimum load-bearing capacity, and the upper bound is restricted by manufacturing and transportation. The wall thickness range is between 8 and 16 millimeters. The lower bound meets the stability requirements of the thin-walled structure, and the upper bound controls the weight and cost. The inclined strut angle range is between 45 and 55 degrees. Within this range, the truss has good load-bearing and force-transferring performance. The chord diameter range is between 20 and 30 millimeters to ensure the strength requirements of the chord under tensile and compressive loads.

[0027] When optimizing the inclined strut angle based on the principle of minimizing the wind resistance coefficient, a relationship function between the inclined strut angle and the wind resistance coefficient is established. This function takes into account the law of the change of the windward area of the truss with the angle and the flow characteristics of the air flow around the truss. During the optimization calculation process, the 45 - 55 degree angle range is divided into 21 calculation points, with an interval of 0.5 degrees between each point, and the wind resistance coefficient values at each angle are calculated respectively. The calculation results show that the wind resistance coefficient first decreases and then increases with the change of the angle, and reaches the minimum value at 50 degrees. The inclined strut crossing angle range of plus or minus 5 degrees from 50 degrees takes into account both the minimization of wind resistance and the tolerance of manufacturing errors. The corresponding wind resistance coefficient is reduced by about 15 percentage points compared with the 45-degree angle and about 12 percentage points compared with the 55-degree angle.

[0028] When optimizing the pre-tension of the steel wire rope according to the goal of maximizing the equivalent stiffness of the composite section, a mechanical model of the composite section of the three materials of the steel wire rope, steel pipe, and concrete is established. The equivalent stiffness calculation considers the prestress effect of the steel wire rope, the bending stiffness of the steel pipe, and the compression stiffness of the concrete. The three form a collaborative working mechanism through the cross-sectional geometric relationship. During the optimization design process, the cross-sectional parameters of the steel pipe, including the outer diameter, wall thickness, and moment of inertia of the cross-section, are determined according to the specifications of the main inclined tube. Then, according to the inner diameter of the steel pipe, the specification parameters of the steel wire rope, including the diameter of the steel wire rope, the number of strands, and the breaking tensile force, are determined. The pre-tension value is determined through optimization calculation, which not only ensures that the steel wire rope remains in a tensioned state under all working conditions but also avoids local instability of the steel pipe caused by excessive pre-tension. The specification parameters of the steel wire rope form a matching relationship with the specifications of the main inclined tube. High-strength steel wire ropes are configured for large-diameter steel pipes, and steel wire ropes of corresponding specifications are configured for small-diameter steel pipes.

[0029] When the main inclined pipe diameter range, the cross - angle of the diagonal bracing, and the wire rope specification parameters are input into the C50 concrete casting process, the casting process determines the concrete dosage and the casting scheme according to the inner diameter of the steel pipe and the wire rope layout. During the construction of the composite section, first, the wire ropes are arranged inside the steel pipe according to the design scheme. The wire ropes are laid along the axial direction of the steel pipe and pre - tensioned. Then, the C50 high - strength concrete is poured from the top of the steel pipe. During the flow of the concrete, the wire ropes are wrapped to form an integrated composite structure. The casting process controls the concrete slump and the casting speed to ensure that the concrete fully fills the internal space of the steel pipe and to avoid the appearance of air bubbles and cavities. The optimized configuration of the wire rope - concrete composite section forms a higher equivalent stiffness and bearing capacity than single materials through the coordinated work of the wire rope prestress, the concrete compressive strength, and the steel pipe restraint effect.

[0030] In a specific embodiment, the process of executing step S103 may specifically include the following steps: Input the dynamic characteristics of the lower truss segment into the fluid - structure interaction control model for the flow around a multi - prism calculation, and obtain the Strouhal number and the vortex shedding frequency of the 12 - sided multi - prism; Based on the vortex shedding frequency, perform chamfering of the edges of the multi - prism geometry to obtain the geometric parameters of the 12 - sided multi - prism with the arc radius parameter and the surface pressure coefficient gradient; According to the geometric parameters of the 12 - sided multi - prism, perform a coordinated design of the mass - stiffness - damping of the TMD system to obtain the TMD device parameters with a mass ratio of 0.02, a frequency ratio of 0.95, and a damping ratio of 0.1; Use the TMD device parameters as constraint conditions to optimize the layout of the viscous dampers, and obtain the layout scheme of 24 viscous dampers with a damping coefficient of 2000 kN·s / m and a velocity exponent of 0.3.

[0031] Specifically, when the dynamic characteristics of the lower truss segment are input into the fluid - structure interaction control model, the fluid - structure interaction control model refers to a calculation model that simultaneously considers the interaction between fluid flow and structural vibration. This model takes the natural frequency, modal vibration mode, and damping characteristics of the truss segment as boundary conditions to establish the flow field calculation domain of the middle multi - prism transition segment. The flow around the multi - prism calculation analyzes the velocity field and pressure field distribution when the air flow flows around the 12 - sided multi - prism by numerically solving the fluid motion equation. The Strouhal number is a dimensionless parameter characterizing the relationship between the vortex shedding frequency and the flow velocity, and is obtained by statistically analyzing the periodic changes of the vortex shedding on the leeward side of the multi - prism. The vortex shedding frequency calculation multiplies the Strouhal number by the incoming flow velocity and divides it by the characteristic size of the multi - prism. This frequency reflects the frequency characteristics of the periodic excitation generated by the vortex shedding on the structure.

[0032] When performing the rounding of the edges and corners of the multi - prism geometry based on the vortex shedding frequency, the rounding process refers to changing the originally sharp edges and corners of the multi - prism to arc transitions, reducing the air - flow separation and the intensity of vortex shedding. During the process, the degree of rounding is determined according to the magnitude of the vortex shedding frequency. The higher the vortex shedding frequency, the more serious the air - flow separation, and a larger arc radius is required for processing. The arc - radius parameter is determined through flow - field analysis to avoid the structural natural frequency after rounding. The surface pressure - coefficient gradient reflects the improvement effect of the rounding process on the pressure distribution. The geometric parameters of the 12 - sided multi - prism include key dimensions such as side length, inscribed - circle diameter, circum - circle diameter, and arc radius, and these parameters are interrelated to form a geometric description. When performing the mass - stiffness - damping co - design of the TMD system according to the geometric parameters of the 12 - sided multi - prism, the TMD system is short for the tuned mass damper, which is a device that suppresses the vibration of the main structure through the vibration of an additional mass block. The mass - stiffness - damping co - design means simultaneously optimizing the mass, spring stiffness, and damper parameters of the TMD to form an optimal matching relationship. The mass ratio of 0.02 represents the ratio of the TMD mass to the structure mass, which is determined by balancing the control effect and cost. If it is too small, the control effect is not obvious; if it is too large, the structural burden increases. The frequency ratio of 0.95 represents the ratio of the TMD frequency to the structure frequency, and this ratio being slightly less than 1.0 forms the best tuning effect. The damping ratio of 0.1 represents the ratio of the damping of the TMD system to the critical damping, and this value is determined through optimization calculations to balance the vibration - suppression effect and energy dissipation.

[0033] When optimizing the layout of the viscous damper with the TMD device parameters as the constraint conditions, the viscous damper is a device that dissipates vibration energy through the flow resistance of the viscous medium, and the layout optimization means determining the optimal installation position and parameters of the damper in the structure. During the optimization process, the TMD device parameters are used as known conditions, and based on the TMD control effect, the viscous damper is further arranged to enhance the vibration control. The damping coefficient of 2000 kN·s / m represents the proportional relationship between the damping force generated by the damper and the velocity, and this value is determined through structural - response analysis and damper - performance matching. The velocity exponent of 0.3 represents the non - linear relationship exponent between the damping force and the velocity, and this exponent enables the damper to maintain stable control performance under different vibration intensities. The layout scheme of 24 viscous dampers determines the position coordinates, installation angles, and connection methods of each damper through an optimization algorithm, forming a uniformly distributed vibration - control network.

[0034] In a specific embodiment, the process of executing step S104 may specifically include the following steps: Input the vibration - control results of the middle multi - prism transition section into the aero - elastic stability discrimination model for eigenvalue solution to obtain the lift coefficient, drag coefficient, and aerodynamic derivatives; Based on the aerodynamic derivatives, the number of segments of the cylindrical section is optimized with respect to the Reynolds number, resulting in a number distribution of a multi-segment cylindrical structure with 18 segments for heights of 200 - 280 meters, 12 segments for heights of 280 - 320 meters, and 6 segments for heights of 320 - 360 meters; According to the number distribution, aerodynamic drag reduction design is carried out on the trapezoidal longitudinal ribs, resulting in a trapezoidal longitudinal rib configuration with a rib height of 200 - 800 mm, a rib width ratio of 0.6, and a rib spacing of 600 mm; The trapezoidal longitudinal rib configuration is input into the geometric stiffness matrix for pre-tension optimization calculation, resulting in pre-tension gradient values of 150 kN for the bottom layer, 120 kN for the middle layer, and 90 kN for the top layer; Based on the pre-tension gradient values, a hierarchical layout design is carried out for the steel wire ropes, resulting in a hierarchical pre-tension distribution with azimuths of 0°, 120°, and 240° for the first layer and azimuths of 60°, 180°, and 300° for the second layer.

[0035] Specifically, when the vibration control results of the middle multi-faceted transition section are input into the aeroelastic stability discrimination model, the vibration control results include the vibration reduction effect of the TMD device, the damping enhancement effect of the viscous damper, and the correction values of the dynamic parameters of the transition section. The aeroelastic stability discrimination model is a mathematical model for analyzing whether the structure undergoes aeroelastic instability under wind loads. This model calculates the stability boundary of the interaction between the structure and the airflow through an eigenvalue solution method. In the eigenvalue solution process, a coupled system of equations of the aerodynamic matrix and the structural dynamics matrix is established, and the real and imaginary parts of the system eigenvalues are obtained through numerical calculation. A negative real part of the eigenvalue indicates system stability, and a positive real part indicates instability. The lift coefficient reflects the magnitude of the aerodynamic force perpendicular to the oncoming flow direction, the drag coefficient reflects the magnitude of the aerodynamic force parallel to the oncoming flow direction, and the aerodynamic derivatives reflect the rate of change of the aerodynamic force with respect to the angle of attack and the pitch angular velocity. The three together describe the aerodynamic characteristics of the cylindrical section.

[0036] When performing Reynolds number-related optimization of the number of segments of the cylindrical section based on aerodynamic derivatives, the Reynolds number is a dimensionless parameter representing the ratio of the inertial force to the viscous force of the fluid. Reynolds number-related optimization refers to determining the optimal number distribution according to the variation law of the Reynolds number at different heights. During the optimization process, the aerodynamic derivatives are used as constraints to analyze the aeroelastic stability performance under different segment number configurations. The more segments there are, the closer the aerodynamic characteristics are to those of a smooth cylinder, and the fewer segments there are, the more convenient the manufacturing and installation are. For the height range of 200 - 280 meters, the wind speed is relatively high and the Reynolds number is relatively high, so an 18-segment configuration is adopted; for the height range of 280 - 320 meters, the wind speed is medium and the Reynolds number is moderate, so a 12-segment configuration is adopted; for the height range of 320 - 360 meters, the wind speed is relatively low and the Reynolds number is relatively low, so a 6-segment configuration is adopted. The number distribution of the multi-segment cylindrical structure is determined by calculating the Reynolds number values at each height layer by layer and then according to the corresponding relationship between the Reynolds number and the optimal number of segments.

[0037] When conducting the aerodynamic drag reduction design of trapezoidal longitudinal ribs according to the sheet number distribution, the trapezoidal longitudinal ribs are reinforcing ribs with a trapezoidal cross-section arranged along the axial direction of the cylinder. The aerodynamic drag reduction design refers to reducing the air flow resistance by optimizing the geometric shape of the ribs. During the design process, the influence of different rib heights on the surface friction coefficient is analyzed. The variation range of the rib height from 200 to 800 mm takes into account both the drag reduction effect and the structural strength requirements. The greater the height, the more obvious the drag reduction effect, but the more the weight increases. The rib width ratio of 0.6 represents the ratio of the width to the height of the rib, and this ratio is determined through flow field analysis. An excessive ratio increases the windward area, while a too small ratio affects the structural strength. The rib spacing of 600 mm represents the distance between adjacent longitudinal ribs, and this spacing is related to the cylinder diameter and the number of sheets to ensure a uniform and reasonable distribution of the ribs. The geometric parameters of the trapezoidal longitudinal ribs are determined by comprehensively considering the drag reduction effect, structural strength, and manufacturing cost.

[0038] When inputting the configuration of the trapezoidal longitudinal ribs into the geometric stiffness matrix for pre-tension optimization calculation, the geometric stiffness matrix is a stiffness matrix that takes into account the influence of the pre-stress effect on the structural stiffness. The pre-tension optimization calculation refers to determining the optimal distribution of the wire rope pre-tension. During the calculation process, the geometric parameters of the trapezoidal longitudinal ribs are converted into cross-sectional characteristic parameters, including the cross-sectional area, moment of inertia, and section modulus, and then a geometric stiffness matrix considering the pre-stress effect is established. The pre-tension gradient distribution is determined according to the load characteristics and stiffness requirements at different heights. The bottom layer with 150 kN corresponds to the maximum load area and requires the maximum pre-tension. The middle layer with 120 kN corresponds to the load transition area and uses medium pre-tension. The top layer with 90 kN corresponds to the area with a smaller load and uses a smaller pre-tension. The pre-tension gradient values are determined through an optimization algorithm to obtain the optimal distribution under the premise of meeting the strength constraint and stability constraint.

[0039] When conducting the design of the wire rope layered arrangement based on the pre-tension gradient values, the layered arrangement design refers to determining the spatial distribution pattern of the wire ropes at different height layers and different azimuth angles. During the design process, the tensile force of each layer of wire ropes is determined according to the pre-tension gradient values, and then the azimuth angle arrangement of the wire ropes is determined according to the principle of uniform force distribution. The first layer forms a three-point uniform distribution at the azimuth angles of 0°, 120°, and 240°. The second layer is staggered by 60° relative to the first layer at the azimuth angles of 60°, 180°, and 300°. The two-layer staggered arrangement avoids stress concentration and ensures uniform force. The layered pre-tension distribution forms a wire rope tensioning scheme by calculating the pre-tension values and spatial coordinates of each wire rope.

[0040] In a specific embodiment, the process of executing step S105 may specifically include the following steps: Input the dynamic characteristics of the lower truss section, the middle multi-faceted transition section, and the upper cylindrical section into the segmented coupled dynamic model for integrated modeling to obtain the full tower mass matrix, damping matrix, and stiffness matrix; Based on the full-tower mass matrix, damping matrix, and stiffness matrix, the frequency ratio of adjacent segments is coordinately calculated to obtain a frequency ratio range of 0.7 - 1.3 and the continuity constraint conditions of the modal vibration mode. According to the frequency ratio range and continuity constraint conditions, a frequency avoidance matrix is established for resonance avoidance design, and a full-tower frequency avoidance matrix with the first three natural frequencies of 0.12 Hz, 0.31 Hz, and 0.58 Hz is obtained. Taking the full-tower frequency avoidance matrix as a constraint condition, the impedance matching of the inter-segment connection is optimized to obtain the impedance matching parameters of the inter-segment connection with smooth vibration energy transfer and a stress concentration coefficient less than 1.5.

[0041] Specifically, when the dynamic characteristics of the lower truss segment, the middle multi-faceted transition segment, and the upper cylindrical segment are input into the segmented coupled dynamic model, the segmented coupled dynamic model is a mathematical model that couples three paragraphs with different structural forms into an overall structure through the connection interface. The integrated modeling process first extracts the mass distribution, stiffness distribution, and damping characteristics of each segment. The dynamic characteristics of the lower truss segment include the truss node mass, rod stiffness, and material damping. The dynamic characteristics of the middle multi-faceted transition segment include the multi-faceted body mass, bending stiffness, and TMD damping enhancement effect. The dynamic characteristics of the upper cylindrical segment include the cylindrical wall mass, prestress stiffness, and viscous damper contribution. The full-tower mass matrix is formed by assembling the mass distributions of the three segments according to the height coordinates. The damping matrix comprehensively considers the structural damping, material damping, and damping effect of the additional damping device. The stiffness matrix uniformly processes the bending stiffness, axial stiffness, and prestressed geometric stiffness.

[0042] When performing the coordinated calculation of the frequency ratio of adjacent segments based on the full-tower mass matrix, damping matrix, and stiffness matrix, the coordinated calculation of the frequency ratio refers to analyzing the relationship between the natural frequency ratios of adjacent structural segments to avoid local resonance phenomena. In the coordinated calculation process, the first three natural frequencies of each segment are extracted, and the frequency ratios of adjacent segments are calculated. The frequency ratio range of 0.7 - 1.3 represents the allowable range of the frequency ratios of adjacent segments. Too small or too large values will both lead to uncoordinated vibration transfer. The continuity constraint conditions of the modal vibration mode require that the vibration mode slopes at the connection of adjacent segments are continuous, avoiding the dynamic amplification effect caused by sudden changes in the vibration mode. The constraint conditions describe the displacement continuity and rotation continuity at the connection through mathematical expressions to ensure the smooth transfer of vibration energy between segments.

[0043] When establishing the frequency avoidance matrix according to the frequency ratio range and the continuity constraint condition, the frequency avoidance matrix arranges the natural frequencies and excitation frequencies of the structure in a matrix form and is a mathematical tool for checking frequency conflicts. Resonance avoidance design makes the natural frequencies avoid the impeller passing frequency and its multiples by adjusting the structural parameters. The first three natural frequencies of 0.12 Hz, 0.31 Hz, and 0.58 Hz correspond to the first bending mode, the second bending mode, and the first torsional mode of the structure respectively. The establishment process of the frequency avoidance matrix for the entire tower includes three steps: frequency extraction, matrix construction, and conflict checking. The difference between any two frequencies in the matrix must be greater than the safe frequency bandwidth to ensure that resonance does not occur.

[0044] When using the frequency avoidance matrix for the entire tower as a constraint condition to optimize the impedance matching between sections, impedance matching optimization refers to the optimization process of adjusting the connection parameters to minimize the reflection when the vibration wave is transmitted between sections. The connection between sections includes two interfaces: the connection between the truss and the multi-faceted section and the connection between the multi-faceted section and the cylindrical section. The impedance matching of each interface needs to consider the impedance difference between the two sections of the structure. Smooth transmission of vibration energy requires the impedance to be continuous at the connection. The impedance is equal to the square root of the product of stiffness and mass. Impedance matching is achieved by adjusting the connection stiffness. The constraint condition that the stress concentration factor is less than 1.5 limits the stress amplification factor at the connection, and the requirements are met through the optimization of the connection geometric parameters and the design of the transition structure. The impedance matching parameters include the connection stiffness coefficient, the connection damping coefficient, and the geometric transition parameters, forming an optimization scheme for the connection between sections.

[0045] In a specific embodiment, the process of executing step S106 may specifically include the following steps: Input the design scheme of the three-section combined structure into the large eddy simulation numerical test platform for flow field modeling to obtain the computational domain grid with a diameter of 15 times in the upwind direction, 30 times in the downwind direction, and 10 times in the lateral direction; Based on the computational domain grid, perform multi-condition combinations for wind speeds of 3 - 25 m / s, turbulence intensities of 5% - 25%, and wind direction angles of 0 - 180 degrees to obtain a coupling verification matrix with 525 verification conditions; Input the coupling verification matrix into the fluid-structure interaction algorithm for time-domain response calculation to obtain verification results with a maximum displacement less than 1 / 116 of the tower height, a maximum stress less than 254 MPa, and a fatigue damage degree less than 0.5; According to the verification results, finally confirm and optimize the design parameters to obtain the target design parameters that meet the requirements of a super height of 360 m and a design life of 25 years.

[0046] Specifically, when the three-section combined structure design scheme is input into the large-eddy simulation numerical test platform, the large-eddy simulation numerical test platform is a computational platform that uses the large-eddy simulation algorithm to solve fluid motion. This platform obtains accurate flow field information by directly solving the large-scale vortex motion and modeling the influence of small-scale vortices. In the process of flow field modeling, the size of the computational domain is first determined according to the geometric dimensions of the three-section combined structure. 15 times the diameter in the upwind direction ensures the full development of the incoming flow, 30 times the diameter in the downwind direction ensures the complete expansion of the wake, and 10 times the diameter on the side avoids the influence of boundary effects. The generation of the computational domain grid adopts a combination of structured grids and unstructured grids. The boundary layer grid is used on the structure surface to ensure the accurate capture of the flow near the wall, and the tetrahedral grid is used in the far field to reduce the computational amount. The total number of grids is controlled within a reasonable range to balance the computational accuracy and computational efficiency.

[0047] When performing multi-condition combinations based on the computational domain grid, multi-condition combinations refer to arranging and combining different wind speeds, turbulence intensities, and wind direction angles to form a comprehensive set of verification conditions. The wind speed of 3 - 25 m / s covers the full operating range of the wind turbine from the cut-in wind speed to the cut-out wind speed, and 12 wind speed conditions are obtained by dividing at intervals of 2 m / s. The turbulence intensity of 5% - 25% reflects the turbulence levels under different terrains and meteorological conditions, and 5 turbulence intensity conditions are obtained by dividing at intervals of 5%. The wind direction angle of 0 - 180 degrees considers the main wind-receiving directions of the wind turbine, and 7 wind direction angle conditions are obtained by dividing at intervals of 30 degrees. The 525 verification conditions are obtained through the complete combination of 12×5×7. The coupling verification matrix records the parameter combinations of each condition in matrix form, and each row represents a specific verification condition containing the wind speed value, turbulence intensity value, and wind direction angle value.

[0048] When the coupling verification matrix is input into the fluid-structure interaction algorithm, the fluid-structure interaction algorithm is a numerical algorithm that simultaneously solves the fluid motion equation and the structural dynamics equation and considers the interaction between the two. The time-domain response calculation uses a time-stepping method to gradually solve the dynamic response of the structure under wind loads. In each time step, the flow field is first calculated to obtain the wind loads acting on the structure, then the structural response is calculated to obtain the structural deformation and velocity, and then the structural motion information is fed back to the flow field calculation to update the boundary conditions. The verification results include three key indicators: maximum displacement, maximum stress, and fatigue damage degree. The maximum displacement being less than 1 / 116 of the tower height, i.e., less than 3.1 m, ensures that the structural stiffness meets the requirements. The maximum stress being less than 254 MPa ensures the safety of the material strength. The fatigue damage degree being less than 0.5 ensures the fatigue safety within the 25-year design life.

[0049] When making the final confirmation and optimization adjustment of the design parameters according to the verification results, the optimization adjustment refers to the process of correcting the design parameters that do not meet the requirements based on the results of the verification calculations. The confirmation process checks whether the calculation results under each verification condition meet the design requirements. If a certain index exceeds the limit value, the corresponding design parameters need to be adjusted. The optimization adjustment includes two aspects: structural parameter adjustment and control parameter adjustment. The structural parameter adjustment involves the modification of cross-sectional dimensions, material strength, and geometric shape. The control parameter adjustment involves the optimization of TMD parameters, damper parameters, and pre-tension distribution. The target design parameters are obtained through multiple rounds of iterative optimization. After each round of optimization, the verification calculations are performed again until all indicators meet the requirements, and finally, a complete set of parameters that meet the requirements of a super high height of 360 meters and a design life of 25 years is determined.

[0050] The above describes the design method of the three-section combined structure of the ultra-high wind power tower barrel in the embodiment of the present application. Next, the design system of the three-section combined structure of the ultra-high wind power tower barrel in the embodiment of the present application will be described. Please refer to Figure 2 , an embodiment of the design system of the three-section combined structure of the ultra-high wind power tower barrel in the embodiment of the present application includes: An analysis module, configured to perform multi-physical field collaborative analysis on the wind speed distribution data of the target wind farm through a wind load - structural dynamics - material mechanics coupling algorithm, and obtain the stiffness distribution function and frequency avoidance constraint of the three functional partitions; An optimization module, configured to perform multi-objective optimization processing on the geometric parameters of the lower truss section according to the stiffness distribution function, and obtain the optimized configuration of the diagonal bracing crossing angle, the main diagonal tube specification, and the steel wire rope - concrete composite section; A control module, configured to use the dynamic characteristics of the lower truss section as boundary conditions to perform fluid-structure interaction vibration control design on the middle multi-prism transition section, and obtain the geometric parameters of the 12-sided multi-prism, the TMD device parameters, and the layout scheme of 24 viscous dampers; A design module, configured to perform aeroelastic instability prevention and control design on the upper cylindrical section based on the vibration control results of the middle multi-prism transition section, and obtain the number distribution of multiple cylindrical structures, the trapezoidal longitudinal rib configuration, and the layered pre-tension distribution; A coordination module, configured to perform integrated dynamic coordination processing on the dynamic characteristics of the three sections of the structure, and obtain the full-tower frequency avoidance matrix and the impedance matching parameters of the inter-segment connection; A verification module, configured to perform multi-condition coupling verification on the three-section combined structure design scheme through a large eddy simulation - finite element coupling verification algorithm, and obtain the target design parameters.

[0051] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A design method for a three-section combined structure of an ultra-high wind power generation tower barrel, characterized in that, The method includes: Performing multi - physical - field collaborative analysis on the wind speed distribution data of the target wind farm through a wind load - structural dynamics - material mechanics coupling algorithm to obtain the stiffness distribution function and frequency avoidance constraints of the three - section functional partition; Performing multi - objective optimization on the geometric parameters of the lower truss section according to the stiffness distribution function to obtain the optimized configuration of the diagonal bracing crossing angle, the main diagonal tube specification, and the steel wire rope - concrete composite section; Taking the dynamic characteristics of the lower truss section as boundary conditions, performing fluid - structure interaction vibration control design on the middle multi - prism transition section to obtain the geometric parameters of the 12 - sided multi - prism, the parameters of the TMD device, and the layout scheme of 24 viscous dampers; Based on the vibration control results of the middle multi - prism transition section, performing aeroelastic instability prevention and control design on the upper cylindrical section to obtain the number distribution of multiple cylindrical structures, the configuration of trapezoidal longitudinal ribs, and the layered pre - tension distribution; Performing integrated dynamic coordination processing on the dynamic characteristics of the three - section structure to obtain the full - tower frequency avoidance matrix and the impedance matching parameters of the inter - section connection; Performing multi - condition coupling verification on the three - section combined structure design scheme through a large - eddy simulation - finite - element coupling verification algorithm to obtain the target design parameters.

2. The design method of the three-section combined structure of the ultra-high wind power generation tower barrel according to claim 1, characterized in that The multi - physical - field collaborative analysis on the wind speed distribution data of the target wind farm through the wind load - structural dynamics - material mechanics coupling algorithm to obtain the stiffness distribution function and frequency avoidance constraints of the three - section functional partition includes: Obtaining the wind speed distribution data within the height range of 60 m to 700 m of the target wind farm, calculating the wind load field through the wind speed gradient function to obtain the wind load distribution characteristics of different height segments; Inputting the wind load distribution characteristics into the structural dynamics model for coupled solution to obtain the displacement response and stress distribution of each height segment; Based on the displacement response, constructing the stiffness distribution function in a piece - wise continuous manner to obtain the gradient distribution of the stiffness coefficients in the 0 - 120 m segment, the 120 - 200 m segment, and the 200 - 360 m segment; Establishing frequency avoidance constraints according to the impeller passing frequency of 0.15 - 0.2 Hz for resonance avoidance calculation to obtain the avoidance matrix of the first three - order frequencies and the safety frequency bandwidth parameters.

3. The design method of the three-section combined structure of the ultra-high wind power tower barrel according to claim 1, characterized in that, The multi - objective optimization of the geometric parameters of the lower truss section according to the stiffness distribution function to obtain the optimized configuration of the diagonal bracing crossing angle, the main diagonal tube specification, and the steel wire rope - concrete composite section includes: Inputting the stiffness distribution function into the multi - objective optimization model to solve the truss geometric parameters to obtain the range of the main diagonal tube diameter, the wall thickness range, the diagonal bracing angle range, and the chord diameter range; Optimizing the calculation of the diagonal bracing angle range based on the principle of minimizing the wind resistance coefficient to obtain the diagonal bracing crossing angle of 50 degrees plus or minus 5 degrees and the corresponding wind resistance coefficient; Optimizing the design of the steel wire rope pre - tension according to the goal of maximizing the equivalent stiffness of the composite section to obtain the steel wire rope specification parameters and the pre - tension value corresponding to the main diagonal tube specification; Inputting the main diagonal tube diameter range, the diagonal bracing crossing angle, and the steel wire rope specification parameters into the C50 concrete casting process for composite section construction to obtain the optimized configuration of the steel wire rope - concrete composite section.

4. The design method of the three-section combined structure of the ultra-high wind power generation tower barrel according to claim 1, characterized in that, Taking the dynamic characteristics of the lower truss section as boundary conditions, the fluid-structure interaction vibration control design of the middle multi-faceted transition section is carried out, and the geometric parameters of the 12-sided polyhedron, the parameters of the TMD device, and the layout scheme of 24 viscous dampers are obtained, including: Inputting the dynamic characteristics of the lower truss section into the fluid-structure interaction control model for the flow-around calculation of the polyhedron, the Strouhal number and vortex shedding frequency of the 12-sided polyhedron are obtained; Based on the vortex shedding frequency, the edges and corners of the polyhedron geometry are rounded to obtain the geometric parameters of the 12-sided polyhedron with the arc radius parameter and the surface pressure coefficient gradient; According to the geometric parameters of the 12-sided polyhedron, the mass-stiffness-damping collaborative design of the TMD system is carried out to obtain the TMD device parameters with a mass ratio of 0.02, a frequency ratio of 0.95, and a damping ratio of 0.1; Taking the TMD device parameters as constraint conditions, the position optimization layout of the viscous dampers is carried out to obtain the layout scheme of 24 viscous dampers with a damping coefficient of 2000 kN·s / m and a velocity exponent of 0.

3.

5. The design method of the three-section combined structure of the ultra-high wind power generation tower barrel according to claim 1, characterized in that, Based on the vibration control results of the middle multi-faceted transition section, the aeroelastic instability prevention and control design of the upper cylindrical section is carried out, and the number distribution of multiple cylindrical structures, the configuration of trapezoidal longitudinal ribs, and the layered pre-tension distribution are obtained, including: Inputting the vibration control results of the middle multi-faceted transition section into the aeroelastic stability discrimination model for eigenvalue solution, the lift coefficient, drag coefficient, and aerodynamic derivatives are obtained; Based on the aerodynamic derivatives, the Reynolds number correlation optimization of the number of cylindrical sections is carried out to obtain the number distribution of multiple cylindrical structures with 18 slices for 200 - 280 m, 12 slices for 280 - 320 m, and 6 slices for 320 - 360 m; According to the number distribution, the aerodynamic drag reduction design of the trapezoidal longitudinal ribs is carried out to obtain the configuration of trapezoidal longitudinal ribs with a rib height of 200 - 800 mm, a rib width ratio of 0.6, and a rib spacing of 600 mm; Inputting the configuration of the trapezoidal longitudinal ribs into the geometric stiffness matrix for pre-tension optimization calculation, the pre-tension gradient values of 150 kN at the bottom layer, 120 kN in the middle layer, and 90 kN at the top layer are obtained; Based on the pre-tension gradient values, the layered layout design of the steel wire ropes is carried out to obtain the layered pre-tension distribution with the first layer at 0°, 120°, and 240° azimuths and the second layer at 60°, 180°, and 300° azimuths.

6. The design method of the three-section combined structure of the ultra-high wind power tower barrel according to claim 1, characterized in that, Integrating the dynamic characteristics of the three sections for integrated dynamic coordination processing to obtain the full-tower frequency avoidance matrix and the impedance matching parameters for the inter-segment connection, including: Inputting the dynamic characteristics of the lower truss section, the middle multi-faceted transition section, and the upper cylindrical section into the segmented coupled dynamic model for integrated modeling to obtain the full-tower mass matrix, damping matrix, and stiffness matrix; Based on the full-tower mass matrix, damping matrix, and stiffness matrix, the coordination calculation of the frequency ratio between adjacent sections is carried out to obtain the frequency ratio range of 0.7 - 1.3 and the continuity constraint conditions of the modal vibration shape; According to the frequency ratio range and continuity constraint conditions, a frequency avoidance matrix is established for resonance avoidance design to obtain the full-tower frequency avoidance matrix with the first three natural frequencies of 0.12 Hz, 0.31 Hz, and 0.58 Hz respectively; Taking the full-tower frequency avoidance matrix as a constraint condition, impedance matching optimization is carried out for the inter-segment connection to obtain the impedance matching parameters of the inter-segment connection with smooth transfer of vibration energy and a stress concentration coefficient less than 1.

5.

7. The design method of the three-section combined structure of the ultra-high wind power generation tower barrel according to claim 1, characterized in that, The multi-condition coupling verification of the three-section combined structure design scheme is carried out through the large eddy simulation - finite element coupling verification algorithm to obtain the target design parameters, including: The three-section combined structure design scheme is input into the large eddy simulation numerical test platform for flow field modeling to obtain the computational domain grid with a diameter of 15 times the upwind diameter, 30 times the downwind diameter, and 10 times the side wind diameter. Based on the computational domain grid, multi-condition combinations of wind speed from 3 to 25 m / s, turbulence intensity from 5% to 25%, and wind direction angle from 0 to 180 degrees are carried out to obtain the coupling verification matrix of 525 verification conditions. The coupling verification matrix is input into the fluid-structure interaction algorithm for time-domain response calculation to obtain the verification results with a maximum displacement less than 1 / 116 of the tower height, a maximum stress less than 254 MPa, and a fatigue damage degree less than 0.

5. According to the verification results, the design parameters are finally confirmed and optimized and adjusted to obtain the target design parameters that meet the requirements of a super height of 360 m and a design life of 25 years.

8. The design method of the three-section combined structure of the ultra-high wind power generation tower barrel according to claim 1, characterized in that, The main design of the middle multi-edge transition section and the upper cylindrical section is the keel reinforcement point, and the keel structure is a trapezoidal area with longitudinal flanges skillfully matched.

9. The design method of the three-section combined structure of the ultra-high wind power generation tower barrel according to claim 1, characterized in that An inner circumferential flange is installed every 4 m in the middle multi-edge transition section and the upper cylindrical section, and its structure is a wire rope tensioning and adjustable type.

10. A design system for a three-section combined structure of an ultra-high wind power generation tower barrel, characterized in that, For implementing the design method of the three-section combined structure of the ultra-high wind power generation tower barrel as described in any one of claims 1-9, the design system of the three-section combined structure of the ultra-high wind power generation tower barrel includes: An analysis module for performing multi-physical field collaborative analysis on the wind speed distribution data of the target wind farm through a wind load - structural dynamics - material mechanics coupling algorithm to obtain the stiffness distribution function and frequency avoidance constraints of the three functional zones. An optimization module for performing multi-objective optimization processing on the geometric parameters of the lower truss section according to the stiffness distribution function to obtain the optimized configuration of the diagonal bracing crossing angle, the main diagonal pipe specification, and the steel wire rope - concrete composite section. A control module for using the dynamic characteristics of the lower truss section as boundary conditions to carry out fluid-structure interaction vibration control design for the middle multi-edge transition section to obtain the geometric parameters of the 12-sided multi-edge body, the TMD device parameters, and the layout scheme of 24 viscous dampers. A design module for performing aeroelastic instability prevention and control design on the upper cylindrical section based on the vibration control results of the middle multi-edge transition section to obtain the number distribution of multiple cylindrical structures, the trapezoidal longitudinal rib configuration, and the hierarchical pre-tension distribution. A coordination module for performing integrated dynamic coordination processing on the dynamic characteristics of the three sections of the structure to obtain the full-tower frequency avoidance matrix and the impedance matching parameters of the inter-segment connection. A verification module for performing multi-condition coupling verification on the three-section combined structure design scheme through the large eddy simulation - finite element coupling verification algorithm to obtain the target design parameters.

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