Method, system, device and medium for determining flutter value of wind turbine blades

Abstract

The present application relates to the technical field of wind turbines, and specifically provides a method, system, device and medium for determining the flutter value of a wind turbine blade, aiming to solve the problem that the use of dynamic models to calculate flutter values does not take into account the influence of fluid flow on the structural motion of the blades. The method comprises: establishing a structural motion equation of the flutter response based on the structure of the wind turbine blade, numerically simulating the two-dimensional flow field to establish a flow control equation, establishing a coupled system equation based on the structural motion equation and the flow control equation, and solving the coupled system equation to obtain the flutter value. On the one hand, the present application uses the structural motion equation to describe the dynamics and force conditions of the wind turbine blade structure, and on the other hand, uses the flow control equation to describe the flow field data around the wind turbine blade, and then solves the coupled system equation to obtain the flutter value. This solves the problem that the use of dynamic models to calculate flutter values does not take into account the influence of fluid flow on the structural motion of the blades.

Description

Technical Field

[0001] The present application relates to the technical field of wind turbines, and in particular to a method, system, device and medium for determining the flutter value of a wind turbine blade. Background Art

[0002] With the trend toward larger wind turbines, the aspect ratio of blades has increased dramatically, leading to a growing problem of stall flutter. Stall flutter is an unstable vibration caused by airflow impacting blades during high-speed rotation. Stall flutter can damage the blade structure, reduce efficiency, or even cause equipment failure. Therefore, calculating blade flutter values is crucial for optimizing blade design. Existing techniques typically use dynamic models to calculate flutter values, without considering the impact of fluid flow on the blade structure's motion.

[0003] Accordingly, the art needs a new solution for determining the flutter value of wind turbine blades to solve the above problems. Summary of the Invention

[0004] In order to overcome the above-mentioned defects, the present application is proposed to solve or at least partially solve the technical problem that the flutter value is calculated using a dynamic model without considering the influence of fluid flow on the blade structure movement.

[0005] In a first aspect, a method for determining the flutter value of a wind turbine blade is provided, the method comprising: establishing a structural motion equation of the flutter response based on the structure of the wind turbine blade; performing numerical simulation on a two-dimensional flow field to establish a flow control equation; establishing a coupled system equation based on the structural motion equation and the flow control equation; and solving the coupled system equation to obtain a flutter value.

[0006] In one technical solution of the above-mentioned method for determining the flutter value of a wind turbine blade, the flutter response includes the angular displacement, angular velocity, and angular acceleration of the structural flutter of the wind turbine blade. Establishing the structural motion equation of the flutter response based on the structure of the wind turbine blade includes: simplifying the wind turbine blade into a two-dimensional airfoil with one rotational degree of freedom; and establishing the structural motion equation regarding the angular displacement, angular velocity, and angular acceleration based on the structural parameters of the two-dimensional airfoil.

[0007] In one technical solution of the above-mentioned method for determining the flutter value of a wind turbine blade, the structural motion equations regarding the angular displacement, angular velocity, and angular acceleration established based on the structural parameters of the two-dimensional airfoil are expressed as follows:

[0008]

[0009] Wherein, θ represents the angular displacement, represents the angular velocity, represents the angular acceleration, f s represents the structural natural frequency, c represents the chord length of the airfoil, U ∞ represents the incoming wind speed, ζ represents the structural damping coefficient; C M represents the pitching moment coefficient of the airfoil; m represents the airfoil mass, ρ represents the fluid density; r represents the radius of gyration of the airfoil.

[0010] In one technical solution of the above-mentioned method for numerically determining the flutter of a wind turbine blade, the numerical simulation of the two-dimensional flow field to establish the flow control equation includes: numerically simulating the two-dimensional flow field using an unsteady Reynolds time-averaged method based on a turbulence model to establish the following flow control equation:

[0011]

[0012] Among them, U i 、U j They represent the fluid at point x at time t. i 、y i The velocity component at represents the average velocity of the fluid in the x direction, ρ represents density, p represents pressure, v represents viscosity, S ji Indicates that the fluid at point x at time t i 、y i The strain velocity tensor at , represents the Reynolds stress term.

[0013] In one technical solution of the above-mentioned method for determining the flutter value of a wind turbine blade, the coupled system equation established based on the structural motion equation and the flow control equation is expressed as follows:

[0014]

[0015] Among them, θ n 、 Respectively represent the angular displacement, angular velocity, and angular acceleration at time t, θ n+1 represents the angular displacement at time t+1, C Mn+1 represents the pitching moment coefficient at time t+1.

[0016] In one technical solution of the above-mentioned method for determining the flutter value of a wind turbine blade, solving the coupled system equation to obtain the flutter value includes: solving the flow control equation to obtain the pitching moment coefficient at time t; and iteratively solving the angular displacement at time t+1 based on the pitching moment coefficient at time t and the coupled system equation.

[0017] In one technical solution of the above-mentioned method for determining the flutter value of a wind turbine blade, the method further includes: performing structural optimization or fault analysis on the wind turbine blade according to the flutter value.

[0018] In a second aspect, a system for determining the flutter value of a wind turbine blade is provided, the system comprising: a first simulation module for establishing a structural motion equation of a flutter response based on the structure of the wind turbine blade; a second simulation module for numerically simulating a two-dimensional flow field to establish a flow control equation; a third simulation module for establishing a coupled system equation based on the structural motion equation and the flow control equation; and a solver module for solving the coupled system equation to obtain a flutter value.

[0019] In a third aspect, a smart device is provided, comprising at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program, and when the computer program is executed by the at least one processor, the method in the above-mentioned first aspect or any corresponding technical solution thereof is implemented.

[0020] In a fourth aspect, a computer-readable storage medium is provided, which stores a plurality of program codes, wherein the program codes are suitable for being loaded and run by a processor to execute the method in the above-mentioned first aspect or any corresponding technical solution thereof.

[0021] The above one or more technical solutions of this application have at least one or more of the following beneficial effects:

[0022] In implementing the technical solution of this application, structural motion equations are used, on the one hand, to describe the dynamics and stress conditions of the wind turbine blade structure, while flow control equations are used, on the other hand, to describe the flow field data, such as the pressure, velocity, and stress distribution, of the fluid surrounding the wind turbine blade. Combining these structural motion equations and flow control equations yields a coupled system equation, thereby describing the interaction between structural motion and fluid flow, simulating the aerodynamic characteristics and structural response of blades in complex wind fields, and ultimately solving the coupled system equations to obtain flutter values. This improves the accuracy and reliability of flutter numerical calculations and resolves the issue of using dynamic models to calculate flutter values without considering the impact of fluid flow on blade structural motion. This flutter value can further provide accurate data support for wind turbine blade design and fault analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The disclosure of this application will become more easily understood with reference to the accompanying drawings. Those skilled in the art will readily appreciate that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of this application. Among them:

[0024] Figure 1 This is a flow chart of the main steps of a method for determining a flutter value of a wind turbine blade according to an embodiment of the present application;

[0025] Figure 2a is a schematic diagram of a simplified model of a wind turbine blade according to an embodiment of the present application;

[0026] Figure 2b is a schematic diagram of a kinematic model of an airfoil structure according to an embodiment of the present application;

[0027] Figure 3 1 is a schematic diagram of the overall framework of fluid-solid coupling numerical simulation according to one embodiment of the present application;

[0028] Figure 4 This is a schematic diagram of the main structure of a system for determining the flutter value of a wind turbine blade according to an embodiment of the present application;

[0029] Figure 5 This is a schematic diagram of the connection relationship between the processor and memory of a smart device according to an embodiment of the present application. DETAILED DESCRIPTION

[0030] Some embodiments of the present application are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present application and are not intended to limit the scope of protection of the present application.

[0031] In the description of this application, the terms "first", "second", etc. are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way are interchangeable where appropriate so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices. The terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, an indirect connection through an intermediate medium, or a communication between two elements, a wireless connection, or a wired connection.

[0032] In addition, "module" and "processor" may include hardware, software, or a combination of the two. A module may include hardware circuits, various suitable sensors, communication ports, and memory, and may also include software components, such as program code, or a combination of software and hardware. The processor may be a central processing unit, a microprocessor, an image processor, a digital signal processor, or any other suitable processor. The processor has data and / or signal processing functions. The processor may be implemented in software, hardware, or a combination of the two. Computer-readable storage media include any suitable media that can store program code, such as a magnetic disk, a hard disk, an optical disk, a flash memory, a read-only memory, a random access memory, and the like.

[0033] In addition, if the meaning of "and / or" appears in this application, it includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution in which A and B are satisfied at the same time. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the fact that ordinary technicians in this field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by this application. The term "at least one A or B" or "at least one of A and B" has a similar meaning to "A and / or B" and can include only A, only B, or A and B. The singular terms "one" and "this" can also include plural forms.

[0034] With the trend toward larger wind turbines, the aspect ratio of blades has increased dramatically, increasing structural flexibility and highlighting stall flutter. During blade design and operation, flow separation can occur at the trailing edge of blades operating at high angles of attack, significantly impacting the aerodynamic performance of the blades. Because blades are long and flexible, the coupling of unsteady flow and elastic blades can easily produce stall flutter, severely impacting the fatigue life of the structure and, under certain operating conditions, even causing structural damage, resulting in significant safety hazards and economic losses. Existing calculation methods make it difficult to accurately predict the dynamic response characteristics of these blades at different wind speeds and angles of attack.

[0035] In order to solve the above problems, the present application provides a method for determining the flutter value of a wind turbine blade. Figure 1 , Figure 1 FIG. 1 is a flow chart of the main steps of a method for determining the flutter value of a wind turbine blade according to an embodiment of the present application. Figure 1 As shown, the method for determining the flutter value of a wind turbine blade in the embodiment of the present application mainly includes the following steps S101 to S104:

[0036] Step S101 : establishing a structural motion equation of a flutter response according to the structure of a wind turbine blade.

[0037] In this embodiment, a mathematical expression or model describing the blade flutter response is derived by analyzing the structure and mechanical properties of the wind turbine blade. The flutter response includes the angular displacement, angular velocity, and angular acceleration of the wind turbine blade's structural flutter. The blade's structural and mechanical properties include its kinematic model, natural frequency, mass, density, and other characteristics.

[0038] In one embodiment, establishing the structural motion equation of the flutter response may include the following steps: clarifying the boundary conditions of the model (such as fixed constraints and degrees of freedom), setting the physical properties of the blade structure (such as mass density and stiffness distribution), and introducing necessary assumptions (such as ignoring certain nonlinear effects); based on the linear vibration theory and the actual situation of the blade structure, establishing a differential equation or integral equation describing the dynamic behavior of the blade, namely the structural motion equation, which is used to reflect the motion state of the blade under force and the relationship between force and displacement.

[0039] Step S102: numerically simulate the two-dimensional flow field to establish the flow control equation.

[0040] In this embodiment, the flow governing equations are fundamental mathematical equations describing fluid motion, and they can describe the spatial distribution and temporal variations of physical quantities such as velocity and pressure. Numerical methods are used to model physical phenomena in a two-dimensional flow field to obtain the flow governing equations (e.g., the Reynolds equations, the Newton-Rogers equations, and the Darcy-Weiger equations). These equations reflect the motion patterns of the fluid at different temporal and spatial scales.

[0041] In one embodiment, the process of establishing the flow control equation may include the following steps: deriving a corresponding mathematical model based on the flow characteristics to be studied. For example, to study the flow characteristics of a fluid under certain conditions, a corresponding mathematical model can be derived based on physical laws such as conservation of energy and conservation of momentum. Then, a suitable numerical method (such as finite difference method, finite volume method, finite element method) is selected as the numerical model. The flow field is divided into many small grid cells to obtain a discretized grid, and finally the selected numerical method and grid are used to establish a research model.

[0042] Step S103: establishing a coupled system equation based on the structural motion equation and the flow control equation.

[0043] In this embodiment, the structural motion equation established in step S101 is combined with the flow control equation established in step S102 to obtain a coupled system equation that describes the interaction between structural motion and fluid flow, thereby achieving the purpose of simulating the aerodynamic characteristics and structural response of the blade in a complex wind field.

[0044] In one embodiment, establishing the coupled system equations may be to use flow field data such as velocity and pressure in the fluid dynamics control equations as inputs to the structural motion equations.

[0045] Step S104: Solve the coupled system equation to obtain a flutter value.

[0046] In this embodiment, the coupled system equations obtained in step S103 are solved to obtain a flutter (response) value. Specifically, the coupled system equations can be discretized using numerical methods such as the time-stepping method and the finite element method using CFD (Computational Fluid Dynamics) and CSD (Computational Structure Dynamics) solvers, and then iteratively solved. Because the coupled system equations account for the interaction and influence between the fluid and the solid, the wind turbine blade flutter values calculated using this method are more accurate and reliable.

[0047] Based on the method described in steps S101 to S104 above, the structural equations of motion are used to describe the dynamics and forces acting on the wind turbine blade structure. Furthermore, the flow control equations are used to describe the flow field data, such as the pressure, velocity, and stress distribution, of the fluid surrounding the wind turbine blade. By combining the structural equations of motion and the flow control equations, a coupled system equation is generated, and the flutter value is obtained by solving the coupled system equations. This improves the accuracy and reliability of flutter value calculations and addresses the issue of using dynamic models to calculate flutter values without considering the impact of fluid flow on the blade structure's motion.

[0048] In one embodiment of the present application, the flutter response includes the angular displacement, angular velocity, and angular acceleration of the wind turbine blade structure flutter. The above step S101 may further include the following steps S1011 and S1012:

[0049] Step S1011 , simplifying the wind turbine blade into a two-dimensional airfoil with one rotational degree of freedom.

[0050] In this embodiment, if Figure 2a As shown, the vertical section of the wind turbine blade is a two-dimensional airfoil. The following assumptions are made for the wind turbine blade:

[0051] (1) Simplify the wind turbine blade into a two-dimensional airfoil.

[0052] (2) The simplified two-dimensional airfoil has only one rotational degree of freedom, that is, it can rotate freely around the rotation center under the incoming wind, and its structural motion system is a mass-spring-damper system.

[0053] Step S1012: establishing a structural motion equation regarding angular displacement, angular velocity, and angular acceleration based on the structural parameters of the two-dimensional airfoil.

[0054] In this embodiment, if Figure 2b As shown, the (airfoil) structure performs a single-degree-of-freedom pitch motion around the center of rotation. Among them, c represents the chord line of the airfoil, θ0 represents the torsion angle of the blade installation, that is, the blade torsion angle, α represents the (incoming flow) angle of attack, θ represents the angular displacement of the structural flutter, and G represents the horizontal line. It should be noted that the blades are usually not installed horizontally, and there is a fixed value of the inclination angle, that is, the torsion angle θ0. When the wind blows the blade to vibrate, there is a small oscillation based on θ0, which is the angular displacement of the flutter θ. Furthermore, the angle of attack α, the blade torsion angle α, and the flutter angle θ satisfy the following formula:

[0055] α=θ0+θ

[0056] In one embodiment, the relationship between the blade twist angle and the flutter angle is analyzed, and the following structural motion equations regarding angular displacement, angular velocity, and angular acceleration are established based on the laws of physics and the structural parameters of the two-dimensional airfoil:

[0057]

[0058] Where θ represents the angular displacement, represents the angular velocity, represents angular acceleration, f s represents the structural natural frequency, c represents the chord length of the airfoil, U ∞ represents the incoming wind speed, ζ represents the structural damping coefficient; C M represents the pitching moment coefficient of the airfoil; m represents the airfoil mass, ρ represents the fluid density; and r represents the radius of gyration of the airfoil. It should be noted that in the above formula, only angular displacement, angular velocity, angular acceleration, and pitching moment coefficient are unknown variables. The others are structural parameters of the airfoil and can be calculated using conventional methods in the field. For example, airfoil mass m = airfoil density * πr 2 / 4, r = c / 2; radius of gyration

[0059] In one embodiment, the structural motion equations include the pitch moment coefficient C M Other aerodynamic coefficients such as lift coefficient and drag coefficient can also be included according to the specific research problem.

[0060] In one implementation of the embodiment of the present application, the above step S102 may further include the following step S1021:

[0061] Step S1021: Based on the turbulence model, the unsteady Reynolds time-averaged method is used to perform numerical simulation on the two-dimensional flow field to establish the following flow control equation:

[0062]

[0063] Among them, U i 、U j They represent the fluid at point x at time t. i 、y i The velocity component at represents the average velocity of the fluid in the x direction, ρ represents density, p represents pressure, v represents viscosity, S ji Indicates that the fluid at point x at time t i 、y i The strain velocity tensor at , represents the Reynolds stress term.

[0064] In one embodiment of the present application, the second-order Crank-Nicolson method is used to solve the above structural motion equation to obtain the expression for the airfoil flutter angular displacement and its derivative:

[0065]

[0066] Rearranging the above expression, we get:

[0067]

[0068] Then substitute it into the structural motion equation in step S1012 to obtain the following coupled system equation:

[0069]

[0070] Among them, θ n 、 Respectively represent the angular displacement, angular velocity, and angular acceleration at time t, θ n+1 represents the angular displacement at time t+1, C Mn+1 represents the pitching moment coefficient at time t+1.

[0071] In one implementation of the embodiment of the present application, the above step S104 may further include the following steps S1041 and S1042:

[0072] Step S1041 , solving the flow control equation to obtain the pitching moment coefficient at time t.

[0073] In this embodiment, a CFD solver is used to solve the flow governing equations in step S1021 to obtain flow field data, and the pitching moment coefficient at time t is calculated based on the flow field data. Calculating the pitching moment coefficient based on the flow field data can refer to prior art methods or use existing fluid dynamics calculation software, and will not be further described here.

[0074] Step S1042: Iteratively solve the angular displacement at time t+1 based on the pitching moment coefficient at time t and the coupled system equation.

[0075] In this embodiment, see the attached Figure 3 The structural flutter response is solved using the CFD solver and the CSD solver. Specifically, the CFD geometric parameters are the parameters of the fluid motion being studied. A grid is generated, dividing the flow field into many small grid points. Each grid point can be discretized to solve the unsteady flow field and obtain the structural aerodynamic coefficients (such as the pitching moment coefficient). The structural operation (motion) model is solved using the CSD solver. The structural aerodynamic coefficients obtained by CFD are then used as input to the CSD solver to solve the structural motion equations, thereby advancing the solution of the flutter angular displacement at the current moment (time t+1) based on the flutter displacement at the previous moment (time t). It should be noted that after the flutter angular displacement at the current moment is obtained, the flow field data at the next moment has also changed, so the flow domain grid needs to be updated before the flutter angular displacement at the next moment can be solved. As an example, by compiling a grid deformation function, all grids are deformed at each time step. The radial basis function interpolation method is used to update the position and velocity of the airfoil structure, and the flutter angular displacement of the blade is determined by continuous iteration. It is understandable that after obtaining the flutter angular displacement, the angular velocity and angular acceleration of the flutter can be further determined by taking derivatives.

[0076] In one implementation of the embodiment of the present application, the following step S105 may be further included after the above step S104:

[0077] Step S105 : performing structural optimization or fault analysis on the wind turbine blades according to the flutter value.

[0078] In this embodiment, after obtaining the flutter (response) value, the blade structure can be optimized, such as by modifying parameters such as the blade geometry, material selection, and manufacturing process to reduce the flutter value. After modifying the blade structure, the flutter value can be recalculated. By comparing the flutter values before and after the modification, the impact of different flutter angles on the flutter response can be evaluated, and the optimal blade structure can be selected.

[0079] In one embodiment, after determining the flutter angle, further simulation or experimentation can be performed to support fault analysis. For example, fault signatures such as cracks, deformation, and fatigue damage can be added to the simulation model to observe how these signatures affect the flutter response, thereby helping to identify potential causes of failure in the wind turbine blade.

[0080] This application achieves the purpose of predicting and analyzing the dynamic response characteristics of wind turbine blades (such as aerodynamic loads, flutter displacements, and surface stresses) under different wind speeds and angles of attack through a numerical simulation method that couples fluid dynamics and structural mechanics; further achieves the purpose of optimizing blade design, improving its aeroelastic stability, and reducing failure rates. This method can be widely used in the design and operation of wind turbine blades and has certain engineering practical value.

[0081] It should be pointed out that although the various steps in the above embodiments are described in a specific order, those skilled in the art will understand that in order to achieve the effect of the present application, different steps do not have to be performed in such an order. They can be performed simultaneously (in parallel) or in other orders. These adjusted solutions are equivalent to the technical solutions described in this application, and therefore will also fall within the scope of protection of this application.

[0082] Another aspect of the present application provides a system for determining the flutter value of a wind turbine blade, such as Figure 4 As shown, the system includes: a first simulation module 401, which is used to establish a structural motion equation of flutter response based on the structure of the wind turbine blade; a second simulation module 402, which is used to perform numerical simulation on the two-dimensional flow field to establish a flow control equation; a third simulation module 403, which is used to establish a coupled system equation based on the structural motion equation and the flow control equation; and a solver module 404, which is used to solve the coupled system equation to obtain a flutter value.

[0083] It will be understood by those skilled in the art that all or part of the processes in the method for implementing the above embodiment of the present application can also be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, it can implement the steps of the above-mentioned various method embodiments. The computer program includes computer program code, which can be in source code form, object code form, executable file or some intermediate form. The computer-readable storage medium may include: any entity or device, medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory, random access memory, electric carrier signal, telecommunication signal and software distribution medium, etc. that can carry the computer program code.

[0084] Another aspect of the present application provides a computer-readable storage medium.

[0085] In an embodiment of a computer-readable storage medium according to the present application, the computer-readable storage medium can be configured to store a program for executing the above-mentioned method embodiment, which can be loaded and executed by a processor to implement the above-mentioned method for determining the flutter value of a wind turbine blade. For ease of explanation, only the parts related to the embodiment of the present application are shown. For specific technical details not disclosed, please refer to the method section of the embodiment of the present application. The computer-readable storage medium can be a storage device formed by various electronic devices. Optionally, the computer-readable storage medium in the embodiment of the present application is a non-transitory computer-readable storage medium.

[0086] Another aspect of the present application provides a smart device.

[0087] In an embodiment of a smart device according to the present application, the smart device may include at least one processor; and a memory in communication with the at least one processor; wherein the memory stores a computer program, and when the computer program is executed by the at least one processor, the method described in any of the above embodiments is implemented. Figure 5 , Figure 5 exemplarily shows that the memory 11 and the processor 12 are communicatively connected via a bus.

[0088] In some embodiments of the present application, the smart device may further include at least one sensor for sensing information. The sensor is communicatively connected to any type of processor mentioned in the present application. Optionally, the smart device described in the present application may be, but is not limited to, a mobile phone, a tablet computer, a desktop computer, a laptop computer, a handheld computer, a notebook computer, an in-vehicle device, an ultra-mobile personal computer (UMPC), etc., and the embodiments of the present application are not limited thereto.

[0089] Thus far, the technical solution of the present application has been described in conjunction with an embodiment shown in the accompanying drawings. However, it is readily understood by those skilled in the art that the scope of protection of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present application.

Claims

1. A method for determining the flutter value of a wind turbine blade, characterized in that: The method comprises: The structural motion equation of the flutter response is established based on the structure of the wind turbine blade; Conduct numerical simulation of two-dimensional flow field to establish flow control equations; Establishing a coupled system equation based on the structural motion equation and the flow control equation; Solving the coupled system equations to obtain flutter values; The coupled system equation established according to the structural motion equation and the flow control equation is expressed as follows: Among them, θ n 、 Respectively represent the angular displacement, angular velocity, and angular acceleration at time t, θ n+1 represents the angular displacement at time t+1, C Mn+1 represents the pitching moment coefficient at time t+1, r represents the radius of gyration of the airfoil, and ζ represents the structural damping coefficient; Solving the coupled system equation to obtain a flutter value includes: Solving the flow control equation to obtain the pitching moment coefficient at time t; The angular displacement at time t+1 is iteratively solved according to the pitching moment coefficient at time t and the coupled system equation.

2. The method according to claim 1, characterized in that The flutter response includes the angular displacement, angular velocity, and angular acceleration of the wind turbine blade structure flutter. The structural motion equation of the flutter response is established based on the structure of the wind turbine blade, including: Simplifying the wind turbine blade into a two-dimensional airfoil with one rotational degree of freedom; A structural motion equation regarding the angular displacement, angular velocity, and angular acceleration is established based on the structural parameters of the two-dimensional airfoil.

3. The method according to claim 2, characterized in that The structural motion equations regarding the angular displacement, angular velocity, and angular acceleration established based on the structural parameters of the two-dimensional airfoil are expressed as follows: k s =2πf s c / U ∞ μ=4m / (prc 2 ) Wherein, θ represents the angular displacement, represents the angular velocity, represents the angular acceleration, f s represents the structural natural frequency, c represents the chord length of the airfoil, U ∞ represents the incoming wind speed, ζ represents the structural damping coefficient; C M represents the pitching moment coefficient of the airfoil; m represents the airfoil mass, ρ represents the fluid density; r represents the radius of gyration of the airfoil.

4. The method according to claim 3, characterized in that The method of numerically simulating the two-dimensional flow field and establishing the flow control equation includes: Based on the turbulence model, the unsteady Reynolds time-averaged method is used to numerically simulate the two-dimensional flow field and establish the following flow control equations: Among them, U i 、U j They represent the velocity components of the fluid in the x and y directions at time t, represents the average velocity of the fluid in the x direction, ρ represents the fluid density, p represents the pressure, v represents the viscosity, S ji Indicates that the fluid at point x at time t i 、x j The strain velocity tensor at , represents the Reynolds stress term.

5. The method according to claim 1, wherein The method further comprises: Structural optimization or fault analysis is performed on the wind turbine blades according to the flutter values.

6. A system for determining the flutter value of a wind turbine blade, characterized in that: The system comprises: A first simulation module is used to establish a structural motion equation of a flutter response according to the structure of the wind turbine blade; The second simulation module is used to perform numerical simulation on the two-dimensional flow field and establish the flow control equation; A third simulation module is used to establish a coupled system equation based on the structural motion equation and the flow control equation; A solver module, configured to solve the coupled system equations to obtain a flutter value; The coupled system equation established according to the structural motion equation and the flow control equation is expressed as follows: Among them, θ n 、 Respectively represent the angular displacement, angular velocity, and angular acceleration at time t, θ n+1 represents the angular displacement at time t+1, C Mn+1 represents the pitching moment coefficient at time t+1, r represents the radius of gyration of the airfoil, and ζ represents the structural damping coefficient; Solving the coupled system equation to obtain a flutter value includes: Solving the flow control equation to obtain the pitching moment coefficient at time t; The angular displacement at time t+1 is iteratively solved according to the pitching moment coefficient at time t and the coupled system equation.

7. A smart device, characterized in that: include: at least one processor; as well as a memory communicatively coupled to the at least one processor; The memory stores a computer program, and when the computer program is executed by the at least one processor, the method according to any one of claims 1 to 5 is implemented.

8. A computer-readable storage medium storing a plurality of program codes, characterized in that: The program code is suitable for being loaded and executed by a processor to perform the method according to any one of claims 1 to 5.

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