Method, system, device and medium for evaluating stall flutter stability of airfoil structures

Abstract

The application relates to the technical field of vibration evaluation, and particularly provides a wing type structure stall flutter stability evaluation method, system, device and medium. The wing type structure comprises a wing type piece and a tuned mass damper, the wing type structure stall flutter stability evaluation method comprises the following steps: constructing a continuous state space equation of the wing type structure based on structural parameters of the wing type structure; constructing a continuous state space equation of an aerodynamic force system based on system identification; constructing a state space analysis model of a coupled system based on the continuous state space equation of the wing type structure and the continuous state space equation of the aerodynamic force system; and evaluating stall flutter stability of the wing type structure based on the state space analysis model of the coupled system. The application can perform aerodynamic elastic stability analysis and optimal design on the wing type structure with the tuned mass damper, so that the safety of the wing type structure in the operation process is effectively ensured, and personal and property losses are reduced.

Description

Technical Field

[0001] This application relates to the field of vibration assessment technology, specifically to a method, system, equipment, and medium for assessing the stability of airfoil structures during stall flutter. Background Technology

[0002] In the aviation and wind energy sectors, stall flutter is a typical aeroelastic instability phenomenon, typically occurring under extreme conditions such as high angle-of-attack flight or strong gusts. This phenomenon involves complex aeroelastic interactions and nonlinear aerodynamic characteristics, and is commonly found in critical components such as large wind turbine blades, helicopter rotors, and aircraft wings. Under the influence of stall-separated flow, these structures are highly susceptible to large-amplitude frequency-locked vibrations. These vibrations not only significantly reduce the aerodynamic efficiency of the structure but also lower the critical flutter velocity, leading to structural fatigue or even failure, posing a serious threat to flight performance and safety. Therefore, assessing and analyzing the stall flutter behavior of airfoil structures is crucial for ensuring the safe operation of aviation and wind energy equipment.

[0003] Accordingly, there is a need in the field for a new scheme for evaluating the stall flutter stability of airfoils to address the above problems. Summary of the Invention

[0004] In order to overcome the above-mentioned deficiencies, this application is made to solve or at least partially solve the technical problem of evaluating the stall flutter stability of airfoil structures.

[0005] In a first aspect, a method for evaluating the stall flutter stability of an airfoil structure is provided. The airfoil structure includes an airfoil component and a tuned mass damper. The method includes: constructing a continuous state-space equation for the airfoil structure based on its structural parameters; constructing a continuous state-space equation for an aerodynamic system based on system identification; constructing a state-space analysis model of the coupled system based on the continuous state-space equations of the airfoil structure and the aerodynamic system; and evaluating the stall flutter stability of the airfoil structure based on the state-space analysis model of the coupled system.

[0006] In one technical solution of the above-mentioned airfoil structure stall flutter stability assessment method, the step of constructing the continuous state space equation of the airfoil structure based on the structural parameters of the airfoil structure includes: establishing the structural motion equation of the airfoil structure based on the structural parameters of the airfoil structure; and constructing the continuous state space equation of the airfoil structure based on the structural motion equation of the airfoil structure.

[0007] In one technical solution of the above-mentioned airfoil structure stall flutter stability assessment method, the structural parameters of the airfoil structure include the parameter information of the airfoil components and the parameter information of the tuned mass damper; the step of establishing the structural motion equation of the airfoil structure based on the structural parameters of the airfoil structure includes: establishing the structural motion equation of the airfoil structure based on the parameter information of the airfoil components and the parameter information of the tuned mass damper, wherein the parameter information of the airfoil components includes mass, damping, spring stiffness, flutter angular displacement, flutter angular velocity, flutter angular acceleration and aerodynamic information, and the parameter information of the tuned mass damper includes mass, damping, spring stiffness, flutter angular displacement, flutter angular velocity and flutter angular acceleration.

[0008] In one technical solution of the above-mentioned airfoil structure stall flutter stability assessment method, the step of constructing the continuous state space equation of the airfoil structure based on the structural motion equation of the airfoil structure includes: converting the structural motion equation of the airfoil structure into a differential form of the structural motion equation; defining state variables, and using the state variables to convert the differential form of the structural motion equation into a continuous state space equation.

[0009] In one technical solution of the above-mentioned airfoil structure stall flutter stability assessment method, the step of constructing the continuous state-space equation of the aerodynamic system based on system identification includes: establishing a multi-input multi-output autoregressive model based on system identification, wherein the input data of the autoregressive model is the flutter angular displacement of the airfoil structure, and the output data is the torque of the aerodynamic force on the airfoil structure; defining a state vector, and using the state vector to transform the autoregressive model into a discrete state-space equation; and performing a bilinear transformation on the discrete state-space equation to obtain the continuous state-space equation of the aerodynamic system.

[0010] In one technical solution of the above-mentioned airfoil structure stall flutter stability assessment method, the construction of a state-space analysis model of the coupled system based on the continuous state-space equation of the airfoil structure and the continuous state-space equation of the aerodynamic system includes: coupling the continuous state-space equation of the airfoil structure and the continuous state-space equation of the aerodynamic system to form a closed-loop feedback process, thereby obtaining the state-space analysis model of the coupled system.

[0011] In one technical solution of the above-mentioned airfoil structure stall flutter stability assessment method, the assessment of the stall flutter stability of the airfoil structure based on the state-space analysis model of the coupled system includes: solving the matrix eigenvalues ​​of the state-space analysis model of the coupled system, where the real part of the matrix eigenvalues ​​is the damping of the coupled system and the imaginary part is the frequency of the coupled system; and assessing the stall flutter stability of the airfoil structure based on the matrix eigenvalues ​​to determine the stable state of the airfoil structure.

[0012] In a second aspect, a stall flutter stability assessment system for an airfoil structure is provided. The airfoil structure includes an airfoil component and a tuned mass damper. The system includes: a first construction module for constructing a continuous state-space equation for the airfoil structure based on its structural parameters; a second construction module for constructing a continuous state-space equation for an aerodynamic system based on system identification; a third construction module for constructing a state-space analysis model of the coupled system based on the continuous state-space equations of the airfoil structure and the aerodynamic system; and an assessment module for assessing the stall flutter stability of the airfoil structure based on the state-space analysis model of the coupled system.

[0013] In a third aspect, an electronic 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, which, when executed by the at least one processor, implements the method described in any of the above-described methods for evaluating the stall flutter stability of airfoils.

[0014] In a fourth aspect, a computer-readable storage medium is provided, wherein a plurality of program codes are stored therein, the program codes being adapted to be loaded and run by a processor to perform the method described in any of the technical solutions of the above-described airfoil structure stall flutter stability assessment method.

[0015] The above-described technical solutions of this application have at least one or more of the following beneficial effects:

[0016] This application provides a method for evaluating the stall flutter stability of an airfoil structure. The airfoil structure includes an airfoil component and a tuned mass damper. The method includes: constructing a continuous state-space equation for the airfoil structure based on its structural parameters; constructing a continuous state-space equation for the aerodynamic system based on system identification; constructing a state-space analysis model of the coupled system based on the continuous state-space equations of the airfoil structure and the aerodynamic system; and evaluating the stall flutter stability of the airfoil structure based on the state-space analysis model of the coupled system. This application constructs a state-space analysis model of the coupled system by combining the continuous state-space equations of the airfoil structure and the aerodynamic system. By comprehensively considering structural and aerodynamic characteristics, it can more realistically reflect actual operating conditions, significantly improve the accuracy of stall flutter stability evaluation, provide accurate data support for the optimized design of the airfoil structure, and thus effectively ensure the safety of the airfoil structure during operation, reducing personal injury and property damage. Attached Figure Description

[0017] The disclosure of this application will become more readily understood with reference to the accompanying drawings. It will be readily understood by those skilled in the art that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of this application. Wherein:

[0018] Figure 1 This is a schematic flowchart of the main steps of an airfoil structure stall flutter stability assessment method according to an embodiment of this application;

[0019] Figure 2 This is a schematic diagram of the kinematic model of an airfoil structure according to an embodiment of this application;

[0020] Figure 3 This is a schematic diagram of the main steps of an airfoil structure stall flutter stability assessment system according to another embodiment of this application;

[0021] Figure 4 This is a schematic diagram of the main structure of an airfoil structure stall flutter stability assessment system according to an embodiment of this application;

[0022] Figure 5 This is a schematic diagram of the main structure of an electronic device according to an embodiment of this application.

[0023] Figure label:

[0024] 11: Memory; 12: Processor; 41: First building block; 42: Second building block; 43: Third building block; 44: Evaluation block. Detailed Implementation

[0025] Some embodiments of this application are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of this application and are not intended to limit the scope of protection of this application.

[0026] In the description of this application, "module" and "processor" can include hardware, software, or a combination of both. A module can include hardware circuitry, various suitable sensors, communication ports, memory, and may also include software components, such as program code, or a combination of software and hardware. A processor can be a central processing unit, microprocessor, image processor, digital signal processor, or any other suitable processor. The processor has data and / or signal processing capabilities. The processor can be implemented in software, in hardware, or a combination of both. Computer-readable storage media includes any suitable medium capable of storing program code, such as magnetic disks, hard disks, optical disks, flash memory, read-only memory, random access memory, etc. The term "A and / or B" means all possible combinations of A and B, such as only A, only B, or A and B. The terms "at least one A or B" or "at least one of A and B" have a similar meaning to "A and / or B" and can include only A, only B, or A and B. The singular terms "a" or "this" can also include plural forms.

[0027] In the aviation and wind energy fields, stall flutter typically occurs under extreme conditions such as high angle-of-attack flight or strong gusts of wind. Stall flutter involves complex aeroelastic interactions and nonlinear aerodynamic characteristics, and is commonly found in critical components such as large wind turbine blades, helicopter rotors, and aircraft wings. Under the influence of stall-separated flow, these structures are highly susceptible to large-amplitude frequency-locked vibrations. These vibrations not only significantly reduce the aerodynamic efficiency of the structure but also lower the critical flutter velocity, leading to structural fatigue or even failure, posing a serious threat to flight performance and safety.

[0028] To address this, this application provides a method for evaluating the stall flutter stability of an airfoil structure. The airfoil structure includes an airfoil component and a tuned mass damper. The method includes: constructing a continuous state-space equation for the airfoil structure based on its structural parameters; constructing a continuous state-space equation for the aerodynamic system based on system identification; constructing a state-space analysis model of the coupled system based on the continuous state-space equations of the airfoil structure and the aerodynamic system; and evaluating the stall flutter stability of the airfoil structure based on the state-space analysis model of the coupled system. This application comprehensively considers structural response and aerodynamic characteristics, and establishes a state-space analysis model of the coupled system, which can accurately evaluate the stall flutter stability of the airfoil structure. This provides precise data support for the optimized design of the airfoil structure, effectively ensuring the safety of the airfoil structure during operation and reducing personal injury and property damage.

[0029] See appendix Figure 1 , Figure 1 This is a schematic flowchart illustrating the main steps of a stall flutter stability assessment method for an airfoil structure according to an embodiment of this application. Figure 1 As shown in the embodiments of this application, the airfoil structure includes an airfoil component and a tuned mass damper. The airfoil structure stall flutter stability assessment method mainly includes the following steps S101 to S104.

[0030] Step S101: Based on the structural parameters of the airfoil, construct the continuous state-space equations of the airfoil.

[0031] In this embodiment, the airfoil structure refers to an airfoil component equipped with a tuned mass damper. The airfoil component can be a wind turbine blade, an aircraft wing, or other structures. A tuned mass damper (TMD) is a vibration control device widely used in structures such as buildings and bridges. The working principle of a tuned mass damper is to effectively absorb and suppress the vibration of the main structure by adding a secondary system with specific mass, stiffness, and damping to the main structure.

[0032] Step S102: Based on system identification, construct the continuous state-space equations of the aerodynamic system.

[0033] In this embodiment, based on system identification, and according to the observed system input and output data, an autoregressive model with linear out-of-band input (ARX) is used to represent the system output as a linear superposition of the system input and output of the previous several steps, thereby constructing the continuous state space equation of the aerodynamic system.

[0034] Step S103: Based on the continuous state-space equations of the airfoil structure and the continuous state-space equations of the aerodynamic system, construct a state-space analysis model of the coupled system;

[0035] Step S104: Evaluate the stall flutter stability of the airfoil structure based on the state-space analysis model of the coupled system.

[0036] Based on the methods described in steps S101 to S104 above, this application couples the continuous state-space equations of the airfoil structure with the continuous state-space equations of the aerodynamic system to construct a state-space analysis model. This model comprehensively considers the dynamic characteristics and aerodynamic effects of the structure, which can more closely reflect actual working conditions and thus truly reflect the dynamic behavior of the airfoil in actual operation. This improves the accuracy of the airfoil stall flutter stability assessment, provides strong data support for the optimized design of the airfoil structure, and ensures the safety of the airfoil structure during operation, reducing the risk of personal injury and property damage caused by structural instability or flutter.

[0037] The following provides further explanation of steps S101 to S104.

[0038] Regarding step S101, in one embodiment, constructing the continuous state-space equation of the airfoil structure based on its structural parameters includes: establishing the structural motion equation of the airfoil structure based on its structural parameters; and constructing the continuous state-space equation of the airfoil structure based on its structural motion equation.

[0039] Specifically, for an airfoil structure with a tuned mass damper, the structural motion equations of the airfoil structure are established by comprehensively considering the structural parameters of the airfoil and the structural parameters of the tuned mass damper, and based on the structural motion equations of the airfoil structure, the continuous state space equations of the airfoil structure are constructed.

[0040] In one embodiment, the structural parameters of the airfoil structure include the parameter information of the airfoil components and the parameter information of the tuned mass damper; the step of establishing the structural motion equation of the airfoil structure based on the structural parameters of the airfoil structure includes: establishing the structural motion equation of the airfoil structure based on the parameter information of the airfoil components and the parameter information of the tuned mass damper, wherein the parameter information of the airfoil components includes mass, damping, spring stiffness, flutter angular displacement, flutter angular velocity, flutter angular acceleration, and aerodynamic information, and the parameter information of the tuned mass damper includes mass, damping, spring stiffness, flutter angular displacement, flutter angular velocity, and flutter angular acceleration.

[0041] Specifically, an airfoil refers to an aircraft wing or wind turbine blade, whose vertical cross-section is assumed to be a two-dimensional airfoil. In this simplified model, the airfoil has only one rotational degree of freedom, meaning it can rotate around a fixed center of rotation. The airfoil's structural motion system can be described using a mass-damped-spring system. The tuned mass damper consists of a mass block, a spring, and a damper. The mounting center of the tuned mass damper is aligned with the rotation center of the airfoil, and their structural motion systems are identical, also being mass-damped-spring systems.

[0042] The motion model of the airfoil structure is as follows Figure 2 As shown, the airfoil structure undergoes a single-degree-of-freedom pitching motion around the rotation center. The following correspondence exists between the incoming flow angle of attack and the torsion angle and flutter angular displacement of the airfoil structure:

[0043] (1)

[0044] in, The torsion angle installed for the airfoil structure, This refers to the flutter angular displacement of the airfoil structure. For incoming flow angle.

[0045] Based on the mass, damping, spring stiffness, flutter angular displacement, flutter angular velocity, flutter angular acceleration, and aerodynamic information of the airfoil components, as well as the mass, damping, spring stiffness, flutter angular displacement, flutter angular velocity, and flutter angular acceleration of the tuned mass damper, the structural motion equations of the airfoil structure are constructed. Here, the aerodynamic information of the airfoil components refers to the torque exerted by the aerodynamic forces on the airfoil structure. The structural motion equations of the airfoil structure are expressed as follows:

[0046] (2)

[0047] in, For the mass of the airfoil, For the flutter angular acceleration of the airfoil, For the damping of the airfoil, The flutter angular velocity of the airfoil. For the spring stiffness of the airfoil, This refers to the flutter angular displacement of the airfoil. To tune the flutter angular displacement of the mass damper The torque exerted by aerodynamic forces on the airfoil structure, To tune the mass of the mass damper, To tune the flutter angular acceleration of the mass damper, To tune the damping of the mass damper, To tune the flutter angular velocity of the mass damper, To adjust the spring stiffness of the mass damper.

[0048] In one embodiment, constructing the continuous state-space equation of the airfoil structure based on the structural motion equation of the airfoil structure includes: converting the structural motion equation of the airfoil structure into a differential form of the structural motion equation; defining state variables, and using the state variables to convert the differential form of the structural motion equation into a continuous state-space equation.

[0049] Specifically, based on the flutter angular displacement of the airfoil and the tuned mass damper, the displacement matrix is ​​defined. for:

[0050]

[0051] The structural motion equations of the airfoil structure are transformed into differential form using the displacement matrix. The differential form of the structural motion equations is expressed as follows:

[0052] (3)

[0053] in, For the quality matrix, Here is the damping matrix. F is the stiffness matrix, and F is the torque matrix. Here is the flutter angular displacement matrix. The first derivative of the flutter angular displacement matrix. The second derivative of the flutter angular displacement matrix, where,

[0054] .

[0055] Define state variables The differential form of the structural motion equations is transformed into continuous state-space equations using state variables. The continuous state-space equations are expressed as follows:

[0056] (4)

[0057] in, Here is the torque matrix, and t is the continuous time. ,in, It is an identity matrix.

[0058] Regarding step S102, in one embodiment, the step of constructing the continuous state-space equation of the aerodynamic system based on system identification includes: establishing a multi-input multi-output autoregressive model based on system identification, wherein the input data of the autoregressive model is the flutter angular displacement of the airfoil structure, and the output data is the torque of the aerodynamic force on the airfoil structure; defining a state vector, and using the state vector to transform the autoregressive model into a discrete state-space equation; and performing a bilinear transformation on the discrete state-space equation to obtain the continuous state-space equation of the aerodynamic system.

[0059] Specifically, the AutoRegressive model with linear out-of-band inputs (ARX) is a model that represents the system output as a linear superposition of the system inputs from previous steps, the external inputs from previous steps, and the external input at the current moment.

[0060] Based on the system identification method, the flutter angular displacement of the airfoil structure is used as input data, and the torque of the aerodynamic force on the airfoil structure is used as output data. A multi-input multi-output autoregressive model is established, which is expressed as:

[0061] (5)

[0062] in, , The vectors represent the system's input and output, respectively, where the input is the flutter angular displacement. The output is the torque exerted by aerodynamic forces on the airfoil structure. = ; , These are the delay orders for the input and output, respectively. , All are coefficient matrices to be identified; To identify the error, it is a dimensionless value used to represent the relative error between the predicted and actual values.

[0063] The least squares method is used to obtain the system's parameters to be identified, and the identification error is then analyzed. To determine the order of the reduced-order model.

[0064] (6)

[0065] in, The total number of data points. The actual value of the i-th data point. This is the predicted or identified value for the i-th data point.

[0066] By designing a reasonable training signal, the input data is the angular displacement of airfoil flutter. The response value was obtained by computational fluid dynamics (CFD) method. The response value is the torque of aerodynamic force on the airfoil structure. .

[0067] Define a state vector, which is represented as:

[0068]

[0069] Using state vectors, the autoregressive model is transformed into a discrete state-space equation for an aerodynamic system. The discrete state-space equation for the aerodynamic system is expressed as:

[0070] (7)

[0071] Among them, matrix , , , These correspond to the system matrix, control matrix, output matrix, and transfer matrix of the aerodynamic system, respectively, and represent the dynamic characteristics of the aerodynamic forces. For discrete moments; This is the input to the system at time k. This represents the output of the aerodynamic system at time k.

[0072]

[0073] By using a bilinear transformation, the discrete state-space equations are converted into continuous state-space equations for the aerodynamic system. The continuous state-space equations for the aerodynamic system are expressed as follows:

[0074] (8)

[0075] in, For state vectors, For continuous time intervals, Let be the system input at time t; Let be the output of the aerodynamic system at time t.

[0076] Regarding step S103, in one embodiment, constructing a state-space analysis model of the coupled system based on the continuous state-space equations of the airfoil structure and the continuous state-space equations of the aerodynamic system includes: coupling the continuous state-space equations of the airfoil structure and the continuous state-space equations of the aerodynamic system to form a closed-loop feedback process, thereby obtaining the state-space analysis model of the coupled system.

[0077] Specifically, the continuous state-space equations of the airfoil structure and the continuous state-space equations of the aerodynamic system are interconnected through feedback to form a closed-loop feedback process, resulting in the state-space analysis model of the coupled system. The state-space analysis model of the coupled system is expressed as follows:

[0078] (9)

[0079] in, For the state variables of the structural system, Let be the state vector of the aerodynamic system. For the system matrix of the structural system, For the control matrix of the structural system, The output matrix of the structural system, For the control matrix of the aerodynamic system, The output matrix of the aerodynamic system. The transfer matrix of the aerodynamic system. This is the system matrix of the aerodynamic system.

[0080] Regarding step S104, in one embodiment, the evaluation of the stall flutter stability of the airfoil structure based on the state-space analysis model of the coupled system includes: solving the matrix eigenvalues ​​of the state-space analysis model of the coupled system, where the real part of the matrix eigenvalues ​​is the damping of the coupled system and the imaginary part is the frequency of the coupled system; and evaluating the stall flutter stability of the airfoil structure based on the matrix eigenvalues ​​to determine the stable state of the airfoil structure.

[0081] Specifically, within the state space, the stability analysis of stall flutter in a coupled system can be transformed into a problem of studying the matrix eigenvalues ​​of the system's state equations. The real and imaginary parts of the matrix eigenvalues ​​represent the damping and frequency of the coupled system, respectively. By solving for the matrix eigenvalues, the stall flutter stability of the airfoil structure can be evaluated based on its real and imaginary parts, thereby determining the system's stable state.

[0082] Specifically, if the real part of the matrix eigenvalues ​​is less than zero, then the system has negative damping. This indicates that after being disturbed, the damping will cause the system to gradually return to its original equilibrium position, thus maintaining a stable state.

[0083] If the real part of the eigenvalues ​​of a matrix is ​​greater than zero, then the system has positive damping. This indicates that the system's damping is insufficient to resist external disturbances, leading to system structure divergence and instability.

[0084] If the real part of the matrix eigenvalues ​​is equal to zero, it indicates that the damping of the system is just enough to counteract external disturbances, so that the system neither diverges nor converges, but remains in a critically stable equilibrium state.

[0085] In the embodiments of this application, a continuous state-space equation for the aerodynamic system is constructed using a system identification method and an autoregressive model with linear out-of-band input (ARX). Simultaneously, based on the structural parameters of the airfoil, the motion equations of the airfoil are established and converted into continuous state-space equations. Finally, the continuous state-space equations of the aerodynamic system and the airfoil are coupled to form a unified coupled system state-space model. Eigenvalue analysis is then performed on the coupled system state-space model, and the stability of the system is evaluated based on the real and imaginary parts of the matrix eigenvalues, providing a reliable reference for the stability analysis of airfoil stall flutter.

[0086] See appendix Figure 3 , Figure 3 This is a schematic flowchart of the main steps of an airfoil structure stall flutter stability assessment system according to another embodiment of this application. Figure 3 As shown, in this embodiment, the structural motion equations of the airfoil are established through a structural dynamics system, and the continuous state-space equations of the airfoil are determined based on the structural motion equations.

[0087] A suitable training signal is designed for the fluid dynamics system, serving as the basis for subsequent system identification. Based on the training signal, an autoregressive model (ARX) is used for system identification to determine the system's input-output relationship. Discrete difference equations are used to simplify the description of the aerodynamic system and reduce model complexity. The dynamic behavior of the aerodynamic system is represented by discrete state-space equations. These discrete state-space equations are then transformed into continuous state-space equations for the aerodynamic system.

[0088] Then, the continuous state-space equations of the aerodynamic system and the structural dynamics system are coupled together to form a state-space analysis model of the coupled system. Eigenvalue analysis is then performed on the state-space analysis model of the coupled system, and the stall flutter stability of the airfoil structure is evaluated based on the matrix eigenvalues.

[0089] It should be noted that although the 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 this application, different steps do not necessarily have to be executed in such an order. They can be executed 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 protection scope of this application.

[0090] Those skilled in the art will understand that all or part of the processes in the method of the above-described embodiment can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form. The computer-readable storage medium can include any entity or device capable of carrying the computer program code, a medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory, a random access memory, an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0091] Another aspect of this application provides a system for evaluating the stall flutter stability of airfoil structures.

[0092] See appendix Figure 4 , Figure 4 This is a schematic diagram of the main structure of an airfoil structure stall flutter stability assessment system according to an embodiment of this application. Figure 4 As shown, the airfoil structure stall flutter stability assessment system in this embodiment mainly includes a first building module 41, a second building module 42, a third building module 43, and an assessment module 44. In some embodiments, one or more of the first building module 41, the second building module 42, the third building module 43, and the assessment module 44 can be combined into a single module.

[0093] In some embodiments, the first construction module 41 can be configured to construct a continuous state-space equation for the airfoil structure based on its structural parameters. The second construction module 42 can be configured to construct a continuous state-space equation for the aerodynamic system based on system identification. The third construction module 43 can be configured to construct a state-space analysis model of the coupled system based on the continuous state-space equations of the airfoil structure and the aerodynamic system. The evaluation module 44 can be configured to evaluate the stall flutter stability of the airfoil structure based on the state-space analysis model of the coupled system. In one embodiment, a description of the specific functions can be found in steps S101 to S104.

[0094] The aforementioned airfoil structure stall flutter stability assessment system is used for performing... Figure 1 The airfoil structure stall flutter stability assessment method shown in the embodiments is similar in technical principle, technical problem solved and technical effect produced. Those skilled in the art can clearly understand that, for the sake of convenience and brevity, the specific working process and related instructions of the airfoil structure stall flutter stability assessment system can be referred to the content described in the embodiments of the airfoil structure stall flutter stability assessment method, which will not be repeated here.

[0095] Another aspect of this application provides an electronic device.

[0096] In one embodiment of an electronic device according to this application, the electronic device may include at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program, which, when executed by the at least one processor, implements the method described in any of the above embodiments. The electronic device described in this application may include driving equipment, intelligent vehicles, robots, and other devices. See appendix. Figure 5 , Figure 5 The image exemplarily illustrates a communication connection between memory 11 and processor 12 via a bus.

[0097] Another aspect of this application provides a computer-readable storage medium.

[0098] In one embodiment of a computer-readable storage medium according to this application, the computer-readable storage medium may be configured to store a program for performing the airfoil stall flutter stability assessment method of the above-described method embodiments. This program may be loaded and run by a processor to implement the above-described airfoil stall flutter stability assessment method. For ease of explanation, only the parts related to the embodiments of this application are shown; for specific technical details not disclosed, please refer to the method section of the embodiments of this application. The computer-readable storage medium may be a storage device comprising various electronic devices. Optionally, in the embodiments of this application, the computer-readable storage medium is a non-transitory computer-readable storage medium.

[0099] The technical solution of this application has been described above with reference to one embodiment shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of this application is obviously not limited to these specific embodiments. Without departing from the principles of this application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of this application.

Claims

1. A method for evaluating the stall flutter stability of an airfoil structure, characterized in that, The airfoil structure includes an airfoil element and a tuned mass damper, and the method includes: Based on the structural parameters of the airfoil, a continuous state-space equation for the airfoil is constructed. Based on system identification, a continuous state-space equation for an aerodynamic system is constructed. Based on the continuous state-space equations of the airfoil structure and the continuous state-space equations of the aerodynamic system, a state-space analysis model of the coupled system is constructed. The stall flutter stability of the airfoil structure is evaluated based on the state-space analysis model of the coupled system. The construction of the continuous state-space equation of the airfoil structure based on its structural parameters includes: establishing the structural motion equation of the airfoil structure based on its structural parameters; and constructing the continuous state-space equation of the airfoil structure based on its structural motion equation. The structural parameters of the airfoil structure include the parameter information of the airfoil components and the parameter information of the tuned mass damper. Establishing the structural motion equation of the airfoil structure based on these parameters includes: establishing the structural motion equation of the airfoil structure based on the parameter information of the airfoil components and the parameter information of the tuned mass damper. The parameter information of the airfoil components includes mass, damping, spring stiffness, flutter angular displacement, flutter angular velocity, flutter angular acceleration, and aerodynamic information. The parameter information of the tuned mass damper includes mass, damping, spring stiffness, flutter angular displacement, flutter angular velocity, and flutter angular acceleration. The structural motion equation of the airfoil structure is expressed as: in, For the mass of the airfoil, For the flutter angular acceleration of the airfoil, For the damping of the airfoil, The flutter angular velocity of the airfoil. For the spring stiffness of the airfoil, For the flutter angular displacement of the airfoil, To tune the flutter angular displacement of the mass damper The torque exerted by aerodynamic forces on the airfoil structure, To tune the mass of the mass damper, To tune the flutter angular acceleration of the mass damper, To tune the damping of the mass damper, To tune the flutter angular velocity of the mass damper, To adjust the spring stiffness of the mass damper.

2. The method for evaluating the stall flutter stability of an airfoil structure according to claim 1, characterized in that, The construction of the continuous state-space equations of the airfoil structure based on the structural motion equations of the airfoil structure includes: The structural motion equations of the airfoil structure are converted into differential form structural motion equations. Define state variables and use them to convert the differential form of the structural motion equations into continuous state-space equations.

3. The method for evaluating the stall flutter stability of an airfoil structure according to claim 1, characterized in that, The construction of continuous state-space equations for the aerodynamic system based on system identification includes: Based on system identification, a multi-input multi-output autoregressive model is established. The input data of the autoregressive model is the flutter angular displacement of the airfoil structure, and the output data is the torque of the aerodynamic force on the airfoil structure. Define a state vector and use the state vector to transform the autoregressive model into a discrete state-space equation; The discrete state-space equations are subjected to a bilinear transformation to obtain the continuous state-space equations of the aerodynamic system.

4. The method for evaluating the stall flutter stability of an airfoil structure according to claim 1, characterized in that, The state-space analysis model of the coupled system is constructed based on the continuous state-space equations of the airfoil structure and the continuous state-space equations of the aerodynamic system, including: By coupling the continuous state-space equations of the airfoil structure and the continuous state-space equations of the aerodynamic system, a closed-loop feedback process is formed, and a state-space analysis model of the coupled system is obtained.

5. The method for evaluating the stall flutter stability of an airfoil structure according to claim 1, characterized in that, The state-space analysis model based on the coupled system is used to evaluate the stall flutter stability of the airfoil structure, including: Solve for the matrix eigenvalues ​​of the state-space analysis model of the coupled system, where the real part of the matrix eigenvalues ​​represents the damping of the coupled system and the imaginary part represents the frequency of the coupled system; Based on the matrix eigenvalues, the stall flutter stability of the airfoil structure is evaluated, and the stable state of the airfoil structure is determined.

6. A stall flutter stability assessment system for airfoil structures, characterized in that, The system is used to perform the airfoil structure stall flutter stability assessment method according to any one of claims 1-5, wherein the airfoil structure includes an airfoil element and a tuned mass damper, and the system includes: The first construction module is used to construct the continuous state-space equations of the airfoil structure based on its structural parameters; The second building module is used to construct the continuous state-space equations of the aerodynamic system based on system identification. The third construction module is used to construct a state-space analysis model of the coupled system based on the continuous state-space equations of the airfoil structure and the continuous state-space equations of the aerodynamic system. The evaluation module is used to evaluate the stall flutter stability of the airfoil structure based on the state-space analysis model of the coupled system.

7. An electronic device comprising at least one processor and at least one memory, said memory being adapted to store a plurality of program codes, characterized in that, The program code is adapted to be loaded and run by the processor to perform the airfoil stall flutter stability assessment method according to any one of claims 1 to 5.

8. A computer-readable storage medium storing a plurality of program codes, characterized in that, The program code is adapted to be loaded and run by a processor to perform the airfoil stall flutter stability assessment method according to any one of claims 1 to 5.

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