Numerical simulation methods, systems, equipment, and media for airfoil structure stall flutter

Abstract

This application relates to the field of flutter analysis technology, specifically providing a method, system, device, and medium for numerical simulation of stall flutter in airfoil structures. The airfoil structure of this application includes an airfoil component and a tuned mass damper. The method includes: acquiring the geometric parameters of the airfoil structure; determining the fluid region of the airfoil structure based on the geometric parameters; generating a flow field mesh based on the fluid region; acquiring the aerodynamic information of the airfoil structure at the current moment; acquiring the flutter angular displacement of the airfoil structure at the previous moment; determining the flutter angular displacement response of the airfoil structure at the current moment based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement of the airfoil structure at the previous moment; and updating the flow field mesh based on the flutter angular displacement response of the airfoil structure at the current moment. This application can simulate the aerodynamic characteristics and structural response of airfoils in complex flow fields, providing accurate data support for the optimized design and stall flutter analysis of airfoils.

Description

Technical Field

[0001] This application relates to the field of flutter analysis technology, specifically to a numerical simulation method, system, electronic device, and storage medium for stall flutter of an airfoil structure. Background Technology

[0002] Under extreme conditions approaching or reaching stall angle of attack, airfoil structures experience complex coupling effects between unsteady aerodynamic forces and flexible structures due to the interaction between nonlinear aerodynamic forces generated by airflow separation, inertial forces, and the structure itself. This leads to aeroelastic self-excited torsional vibrations, a phenomenon known as stall flutter. Stall flutter involves complex coupling between aerodynamics and structure, potentially causing additional dynamic loads, accelerating fatigue accumulation, and even ultimately leading to structural failure. Specifically, stall flutter is characterized by large-scale airflow separation and reattachment processes, resulting in highly nonlinear aerodynamic characteristics. These nonlinear aerodynamic loads generate repeated loading and unloading cycles on the structure, accelerating fatigue damage to structural materials over long periods, potentially leading to structural damage or failure, posing significant safety hazards, and causing corresponding economic losses. Therefore, accurately predicting and simulating the dynamic response characteristics of airfoils under different wind speeds and angles of attack is crucial for ensuring the safe operation of equipment with airfoil structures, extending their service life, and reducing maintenance costs.

[0003] Accordingly, the field needs a new numerical simulation scheme for airfoil structure stall flutter to solve 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 simulating the dynamic response characteristics of airfoil structures under different wind speeds and angles of attack.

[0005] In a first aspect, a numerical simulation method for stall flutter of an airfoil structure is provided. The airfoil structure includes an airfoil component and a tuned mass damper. The method includes: acquiring the geometric parameters of the airfoil structure; determining the fluid region of the airfoil structure based on the geometric parameters; and generating a flow field mesh based on the fluid region; acquiring the aerodynamic information of the airfoil structure at the current moment; acquiring the flutter angular displacement of the airfoil structure at the previous moment; determining the flutter angular displacement response of the airfoil structure at the current moment based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement of the airfoil structure at the previous moment; and updating the flow field mesh based on the flutter angular displacement response of the airfoil structure at the current moment.

[0006] In one technical solution of the above-mentioned numerical simulation method for airfoil stall flutter, obtaining the aerodynamic information of the airfoil at the current moment includes: using a CFD solver, employing the unsteady Reynolds time-averaged method to numerically simulate the flow field, solving the fluid dynamics control equations, and determining the physical information of the flow field grid, wherein the physical information of the flow field grid includes the pressure of the flow field grid nodes; and post-processing the physical information of the flow field grid to determine the aerodynamic information of the airfoil at the current moment.

[0007] In one technical solution of the above-mentioned numerical simulation method for stall flutter of airfoil structures, the step of determining the flutter angular displacement response of the airfoil structure at the current moment based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement of the airfoil structure at the previous moment includes: acquiring a pre-constructed structural motion model of the airfoil structure; and determining the flutter angular displacement response of the airfoil structure at the current moment by using the structural motion model of the airfoil structure based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement of the airfoil structure at the previous moment.

[0008] In one technical solution of the above-mentioned numerical simulation method for airfoil stall flutter, the step of determining the flutter angular displacement response of the airfoil at the current moment based on the aerodynamic information of the airfoil at the current moment and the flutter angular displacement of the airfoil at the previous moment, using the structural motion model of the airfoil, includes: determining the flutter angular displacement response equation based on the flutter angular displacement of the airfoil at the previous moment and the structural motion model of the airfoil; and solving the flutter angular displacement response equation based on the aerodynamic information of the airfoil at the current moment and the flutter angular displacement of the airfoil at the previous moment to obtain the flutter angular displacement response of the airfoil at the current moment.

[0009] In one technical solution of the above-mentioned numerical simulation method for stall flutter of airfoil structures, the step of determining the flutter angular displacement response equation based on the flutter angular displacement of the airfoil structure at the previous moment and the structural motion model of the airfoil structure includes: determining the derivative equation corresponding to the flutter angular displacement of the airfoil structure at the current moment based on the flutter angular displacement of the airfoil structure at the previous moment; and determining the flutter angular displacement response equation based on the derivative equation corresponding to the flutter angular displacement of the airfoil structure at the current moment and the structural motion model of the airfoil structure.

[0010] In one technical solution of the above-mentioned numerical simulation method for airfoil stall flutter, the structural motion model of the airfoil is constructed by the following steps: based on the parameter information of the airfoil, the structural motion equation of the airfoil is established; state variables are defined, and the structural motion equation of the airfoil is converted into the structural motion model of the airfoil based on the state variables.

[0011] In one technical solution of the above-mentioned numerical simulation method for stall flutter of airfoil structures, the parameter information of the airfoil structure includes 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 parameter information of the airfoil structure includes: establishing the structural motion equation of the airfoil components based on the parameter information of the airfoil components; and establishing the structural motion equation of the airfoil structure based on the parameter information of the tuned mass damper and the structural motion equation of the airfoil components.

[0012] In a second aspect, a numerical simulation system for stall flutter of an airfoil structure is provided. The airfoil structure includes an airfoil component and a tuned mass damper. The system includes: a mesh creation module for acquiring the geometric parameters of the airfoil structure, determining the fluid region of the airfoil structure based on the geometric parameters, and generating a flow field mesh based on the fluid region; a first acquisition module for acquiring the aerodynamic information of the airfoil structure at the current moment; a second acquisition module for acquiring the flutter angular displacement of the airfoil structure at the previous moment; a determination module for determining the flutter angular displacement response of the airfoil structure at the current moment based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement of the airfoil structure at the previous moment; and an update module for updating the flow field mesh based on the flutter angular displacement response of the airfoil structure at the current moment.

[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 numerical simulation methods for airfoil structure stall flutter.

[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 above-described numerical simulation methods for airfoil structure stall flutter.

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

[0016] The numerical simulation method for airfoil stall flutter provided in this application includes: acquiring the geometric parameters of the airfoil; determining the fluid region of the airfoil based on the geometric parameters; generating a flow field mesh based on the fluid region; acquiring the aerodynamic information of the airfoil at the current moment; acquiring the flutter angular displacement of the airfoil at the previous moment; determining the flutter angular displacement response of the airfoil at the current moment based on the aerodynamic information of the airfoil at the current moment and the flutter angular displacement of the airfoil at the previous moment; and updating the flow field mesh based on the flutter angular displacement response of the airfoil at the current moment. This application combines the flutter angular displacement of the airfoil at the previous moment with the aerodynamic information of the airfoil at the current moment to perform fluid-structure interaction analysis, thereby determining the flutter angular displacement response of the airfoil under the action of aerodynamic forces at the current moment. It can accurately simulate the aerodynamic characteristics and flutter angular displacement response of the airfoil in complex flow fields, providing reliable data support for airfoil design and stall flutter analysis. 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 a numerical simulation method for stall flutter of an airfoil structure according to an embodiment of this application;

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

[0020] Figure 3 This is a simplified model schematic diagram of a tuned mass damper according to an embodiment of this application;

[0021] Figure 4 This is a schematic flowchart of the main steps of a fluid-structure interaction numerical simulation according to an embodiment of this application.

[0022] Figure 5 This is a schematic diagram of the main structure of a numerical simulation system for stall flutter of an airfoil structure according to an embodiment of this application;

[0023] Figure 6 This is a schematic diagram of the main structure of an electronic device according to an embodiment of this application.

[0024] Figure label:

[0025] 11: Memory; 12: Processor; 51: Mesh creation module; 52: First acquisition module; 53: Second acquisition module; 54: Determination module; 55: Update module. Detailed Implementation

[0026] 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.

[0027] 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.

[0028] When an airfoil approaches or exceeds its stall angle of attack, the nonlinear aerodynamic forces induced by airflow separation interact with the structure, leading to complex coupling effects and subsequently causing self-excited torsional vibration (i.e., stall flutter). Stall flutter increases dynamic loads, accelerates structural fatigue, and may even cause failure. Therefore, accurately predicting and simulating the dynamic response of airfoils under different wind speeds and angles of attack is crucial.

[0029] To address this, the numerical simulation method for airfoil stall flutter provided in this application includes: acquiring the geometric parameters of the airfoil; determining the fluid region of the airfoil based on the geometric parameters; and generating a flow field mesh based on the fluid region; acquiring the aerodynamic information of the airfoil at the current moment; acquiring the flutter angular displacement of the airfoil at the previous moment; determining the flutter angular displacement response of the airfoil at the current moment based on the aerodynamic information of the airfoil at the current moment and the flutter angular displacement of the airfoil at the previous moment; and updating the flow field mesh based on the flutter angular displacement response of the airfoil at the current moment. This application, by combining the flutter angular displacement of the airfoil at the previous moment with the aerodynamic information of the airfoil at the current moment for fluid-structure interaction analysis, can accurately simulate the aerodynamic characteristics and flutter angular displacement response of the airfoil in complex flow fields. This provides reliable data support for airfoil design optimization, stall flutter analysis, and safe operation, and helps improve design accuracy and structural safety.

[0030] See appendix Figure 1 , Figure 1 This is a schematic flowchart illustrating the main steps of a numerical simulation method for stall flutter of an airfoil structure according to an embodiment of this application. Figure 1 As shown, the airfoil structure in this application embodiment includes an airfoil component and a tuned mass damper. The numerical simulation method for stall flutter of the airfoil structure in this application mainly includes the following steps S101 to S105.

[0031] Step S101: Obtain the geometric parameters of the airfoil structure, determine the fluid region of the airfoil structure based on the geometric parameters, and generate a flow field mesh based on the fluid region.

[0032] In this embodiment, based on the obtained geometric parameters of the airfoil structure, the fluid region around the airfoil structure is defined, the fluid flow problem is determined, and based on the determined fluid region, the fluid region is divided into a series of grids to obtain the flow field grid.

[0033] Step S102: Obtain the aerodynamic information of the airfoil structure at the current moment.

[0034] In this embodiment, the airfoil structure is a single-degree-of-freedom system with only one rotational degree of freedom, namely pitch motion about the center of rotation. Since the airfoil's motion is limited to pitch motion about the center of rotation, the main manifestation of aerodynamic forces is torque about the center of rotation. Therefore, the aerodynamic information of the airfoil structure refers to the torque matrix of aerodynamic forces acting on the airfoil structure.

[0035] Step S103: Obtain the flutter angular displacement of the airfoil structure at the previous moment;

[0036] In this embodiment, the flutter angular displacement of the airfoil structure refers to the angular change of the airfoil around the center of rotation under the influence of aerodynamic forces.

[0037] Step S104: Based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement of the airfoil structure at the previous moment, determine the flutter angular displacement response of the airfoil structure at the current moment.

[0038] Step S105: Update the flow field mesh based on the flutter angular displacement response of the airfoil structure at the current moment.

[0039] Based on the methods described in steps S101 to S105 above, this application can accurately simulate the aerodynamic characteristics and structural response of airfoil structures in complex flow fields by obtaining the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement at the previous moment, and performing fluid-structure interaction analysis and adaptive mesh updates at each time step, ensuring the reliability of the simulation results and providing accurate data support for airfoil design and stall flutter analysis.

[0040] The following provides further explanation of steps S101 to S105.

[0041] For step S101, the geometric parameters of the airfoil structure are obtained, the fluid region of the airfoil structure is determined based on the geometric parameters, and a flow field mesh is generated based on the fluid region.

[0042] Specifically, an airfoil structure refers to an airfoil component with a tuned mass damper, which can be an aircraft wing or a wind turbine blade. A tuned mass damper (TMD) is a vibration control device widely used in structures such as buildings, bridges, aircraft, and wind turbines. A TMD effectively absorbs and suppresses structural vibrations by adding an additional mass with specific mass, stiffness, and damping to the main structure. Its working principle is based on resonance: when the main structure vibrates, the mass of the tuned mass damper will move relative to the main structure at a specific frequency, thereby dissipating vibration energy and achieving vibration reduction.

[0043] The geometric parameters of an airfoil include its shape, thickness distribution, and leading and trailing edge positions. Based on these parameters, the fluid region surrounding the airfoil is defined, and relevant parameters for the fluid flow problem, such as geometry, boundary conditions, and fluid properties, are determined. Based on this defined fluid region, it is divided into a series of meshes to obtain the flow field mesh, thus discretizing the continuous fluid problem for easier numerical simulation and analysis.

[0044] For step S102, obtain the aerodynamic information of the airfoil structure at the current moment.

[0045] In one embodiment, obtaining the aerodynamic information of the airfoil structure at the current moment includes: using a CFD solver, employing the unsteady Reynolds time-averaged method to numerically simulate the flow field, solving the fluid dynamics control equations, and determining the physical information of the flow field grid, wherein the physical information of the flow field grid includes the pressure of the flow field grid nodes; and post-processing the physical information of the flow field grid to determine the aerodynamic information of the airfoil structure at the current moment.

[0046] Specifically, CFD (Computational Fluid Dynamics) is a computational technique that uses numerical methods to solve fluid dynamics problems. The Unsteady Reynolds Average Method (URANS) is used to handle the effects of instantaneous fluctuations on the mean flow.

[0047] Using a CFD solver, the two-dimensional flow field was numerically simulated using the unsteady Reynolds time-averaged method to solve the fluid dynamics governing equations. The fluid dynamics governing equations describe the basic laws of fluid motion and include the continuity equation and the Navier-Stokes momentum equation.

[0048] Based on the fluid dynamics governing equations, the fluid dynamics governing equations are discretized at each grid node to obtain a set of algebraic equations. Numerical methods, such as the finite difference method, the finite volume method, or the finite element method, are used to solve the discrete set of equations to determine the physical information of the flow field grid. The physical information of the flow field grid can be the pressure, velocity, density, etc. of the flow field grid nodes.

[0049] The continuity equation and the Navier-Stokes momentum equation are expressed as follows:

[0050]

[0051] In the formula, x is the average velocity of the fluid. i x j These represent spatial coordinates, with subscripts i and j indicating the x and y components respectively, p representing pressure, and t representing time. This represents the rate of change of fluid velocity over time. This represents the convection effect of the fluid velocity field, where ρ is the fluid density. This represents the pressure gradient force, which drives the fluid to flow from a high-pressure region to a low-pressure region. v is the dynamic viscosity coefficient, and S... ji It is the strain rate tensor. It is the average value of the Reynolds stress tensor. This represents viscous force and Reynolds stress.

[0052] The first equation is the continuity equation, which states that mass is conserved in incompressible fluids. It shows that during fluid flow, the product of the fluid density (which is constant if the fluid is incompressible) and the divergence of the velocity field is zero, meaning that the fluid will not accumulate or disappear at any point during the flow. The second equation is the Navier-Stokes momentum equation, which describes the change in fluid momentum.

[0053] In this embodiment, under high Reynolds number conditions, the SSTk-ω turbulence model is selected, the airfoil surface adopts no-slip wall boundary conditions, the flow control equations are solved using the finite volume method and the implicit dual-time propagation method, and the spatial discretization method is a second-order upwind scheme.

[0054] Specifically, the physical information of the flow field mesh refers to the pressure at the flow field mesh nodes. These pressure values ​​reflect the forces exerted by the fluid on the airfoil surface. After determining the pressure at the flow field mesh nodes, post-processing is performed on the pressure at the flow field mesh nodes using Ansys Fluent to perform integration calculations on the pressure of the airfoil structure's flow field mesh nodes, thereby determining the aerodynamic information of the airfoil structure at the current moment.

[0055] For step S103, obtain the flutter angular displacement of the airfoil structure at the previous moment.

[0056] Specifically, the flutter angular displacement of the airfoil structure is determined through iterative calculation. At each time step, the flutter angular displacement is updated based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement at the previous moment.

[0057] Regarding step S104, in one embodiment, determining the flutter angular displacement response of the airfoil at the current moment based on the aerodynamic information of the airfoil at the current moment and the flutter angular displacement of the airfoil at the previous moment includes: acquiring a pre-constructed structural motion model of the airfoil; and determining the flutter angular displacement response of the airfoil at the current moment using the structural motion model of the airfoil based on the aerodynamic information of the airfoil at the current moment and the flutter angular displacement of the airfoil at the previous moment.

[0058] Specifically, a structural motion model of the airfoil is constructed based on the parameter information of the airfoil, and the flutter angular displacement response of the airfoil at the current moment is determined based on the aerodynamic information of the airfoil at the current moment, the flutter angular displacement of the airfoil at the previous moment, and the structural motion model of the airfoil.

[0059] In one embodiment, the structural motion model of the airfoil is constructed using the following steps: establishing the structural motion equation of the airfoil based on the parameter information of the airfoil; defining state variables, and converting the structural motion equation of the airfoil into the structural motion model of the airfoil based on the state variables.

[0060] In one embodiment, the parameter information of the airfoil structure includes the parameter information of the airfoil component and the parameter information of the tuned mass damper; the step of establishing the structural motion equation of the airfoil structure based on the parameter information of the airfoil structure includes: establishing the structural motion equation of the airfoil component based on the parameter information of the airfoil component; and establishing the structural motion equation of the airfoil structure based on the parameter information of the tuned mass damper and the structural motion equation of the airfoil component.

[0061] Specifically, an airfoil structure refers to an airfoil component with a tuned mass damper (TMD). This airfoil component can be an aircraft wing or a wind turbine blade. The tuned mass damper (TMD) is an additional mass-damped-spring system, typically used to suppress structural vibrations. Assuming the vertical cross-section of the airfoil component is a two-dimensional airfoil, and this two-dimensional airfoil has only one rotational degree of freedom, that is, it can rotate freely around the center of rotation, its structural motion system is a mass-damped-spring system.

[0062] Kinematic model of airfoil stall flutter as follows Figure 2 As shown, this model assumes that the airfoil undergoes a single-degree-of-freedom pitching motion around its center of rotation. The relationship between the incoming flow angle of attack, the airfoil flutter angular displacement, and the torsion angle of the airfoil mounting can be expressed as:

[0063] α=θ0+θ1 (2)

[0064] Where θ0 is the torsion angle of the airfoil installation, θ1 is the flutter angular displacement of the airfoil, and α is the angle of attack of the incoming flow.

[0065] First, based on the parameter information of the airfoil, the structural motion equation of the airfoil is established. The parameter information of the airfoil includes mass, damping, spring stiffness, flutter angular displacement, flutter angular velocity, flutter angular acceleration, and aerodynamic information, which refers to the torque exerted by aerodynamic forces on the airfoil. The structural motion equation of the airfoil is expressed as:

[0066]

[0067] Where θ1 is the flutter angular displacement of the airfoil. The flutter angular velocity of the airfoil. Let m1 be the flutter angular acceleration of the airfoil, c1 be the mass of the airfoil, k1 be the damping of the airfoil, k1 be the spring stiffness of the airfoil, and F1 be the torque of the aerodynamic force acting on the airfoil.

[0068] The tuned mass damper consists of a uniform mass block, a spring, and a damper. Its mounting center coincides with the airfoil's rotation center. A simplified model of the tuned mass damper is shown below. Figure 3 As shown. The parameter information of the tuned mass damper includes mass, damping, spring stiffness, flutter angular displacement, flutter angular velocity, and flutter angular acceleration.

[0069] Based on the parameter information of the tuned mass damper and the structural motion equation of the airfoil, the structural motion equation of the airfoil structure is established, and the structural motion equation of the airfoil structure is expressed as:

[0070]

[0071] Where c2 is the damping of the tuned mass damper, k2 is the spring stiffness of the tuned mass damper, and θ2 is the flutter angular displacement of the tuned mass damper. To tune the flutter angular acceleration of the mass damper, Let m2 be the flutter angular velocity of the tuned mass damper, m2 be the mass of the tuned mass damper, and F be the torque of the aerodynamic force acting on the airfoil structure.

[0072] Introducing state variables Based on the state variables, the structural motion equation (4) of the airfoil structure is transformed into the structural motion model of the airfoil structure. The structural motion model of the airfoil structure is expressed as:

[0073]

[0074] Where M is the mass matrix, G is the damping matrix, K is the stiffness matrix, F is the torque matrix of aerodynamic forces acting on the airfoil structure, and ξ is the flutter angular displacement matrix. The first derivative of the flutter angular displacement matrix. Let be the second derivative of the flutter angular displacement matrix, where

[0075]

[0076] In one embodiment, determining the flutter angular displacement response of the airfoil at the current moment based on the aerodynamic information of the airfoil at the current moment and the flutter angular displacement of the airfoil at the previous moment, using the structural motion model of the airfoil, includes: determining the flutter angular displacement response equation based on the flutter angular displacement of the airfoil at the previous moment and the structural motion model of the airfoil; and solving the flutter angular displacement response equation based on the aerodynamic information of the airfoil at the current moment and the flutter angular displacement of the airfoil at the previous moment to obtain the flutter angular displacement response of the airfoil at the current moment.

[0077] In one embodiment, determining the flutter angular displacement response equation based on the flutter angular displacement of the airfoil structure at the previous moment and the structural motion model of the airfoil structure includes: determining the derivative equation corresponding to the flutter angular displacement of the airfoil structure at the current moment based on the flutter angular displacement of the airfoil structure at the previous moment; and determining the flutter angular displacement response equation based on the derivative equation corresponding to the flutter angular displacement of the airfoil structure at the current moment and the structural motion model of the airfoil structure.

[0078] Specifically, using the CSD (Computational Structural Dynamics) solver and employing the second-order Crank-Nicolson method, the derivative equation corresponding to the flutter angular displacement of the airfoil at the current moment is determined based on the flutter angular displacement of the airfoil at the previous moment and its corresponding derivative. Then, based on the derivative equation corresponding to the flutter angular displacement of the airfoil at the current moment and the structural motion model of the airfoil, the flutter angular displacement response equation is constructed. Finally, based on the aerodynamic information of the airfoil at the current moment and the flutter angular displacement at the previous moment, this flutter angular displacement response equation is solved to obtain the flutter angular displacement response of the airfoil at the current moment.

[0079] The CSD solver is a numerical tool used to simulate and analyze the response of structures under dynamic loads. It is widely used in the study of structural vibration, flutter, shock, and other transient behaviors. The Crank-Nicolson method is a second-order accurate time integration method that can predict the state variables and their derivatives at the next time step based on the state variables and their derivatives at the previous time step.

[0080] Specifically, the Crank-Nicolson method is used, based on the flutter angular displacement matrix of the previous time step. and its corresponding first derivative Second derivative The derivative equation corresponding to the flutter angular displacement of the airfoil structure at the current moment is expressed as:

[0081]

[0082] Rearranging the above equations, we obtain the derivative equation corresponding to the flutter angular displacement of the airfoil structure at the current moment:

[0083]

[0084] Where Δt represents the time step, ξ n Let ξ be the flutter angular displacement matrix of the airfoil structure at the previous moment. n+1 This is the flutter angular displacement matrix of the airfoil structure at the current moment.

[0085] Substituting the derivative equation (7) corresponding to the flutter angular displacement of the airfoil structure at the current moment into the structural motion model (5) of the airfoil structure, we obtain:

[0086]

[0087] After further simplification, the flutter angular displacement response equation can be expressed as:

[0088]

[0089] Where M is the mass matrix, G is the damping matrix, K is the stiffness matrix, and F is the torque matrix of aerodynamic forces acting on the airfoil structure.

[0090] The flutter angular displacement matrix ξ of the airfoil structure at the previous moment n and its corresponding first derivative and second derivative And the torque matrix F of the aerodynamic forces acting on the airfoil structure at the current moment, obtained by the CFD solver. n+1 Substituting into equation (9) above, the flutter angular displacement matrix ξ of the airfoil structure at the current moment is calculated. n+1 Determine the flutter angular displacement response of the airfoil structure at the current moment.

[0091] For step S105, the flow field mesh is updated based on the flutter angular displacement response of the airfoil structure at the current moment.

[0092] Specifically, by defining a mesh deformation function, all meshes are deformed at each time step. Based on the flutter angular displacement response of the airfoil at the current moment, the position and velocity of the airfoil are updated using radial basis function interpolation. In each iteration, the flutter angular displacement of the airfoil affects the deformation of the flow field mesh, and the new flow field mesh is then used to calculate the aerodynamic forces at the next moment, thus affecting the motion state of the airfoil. By continuously advancing the iterations, the dynamic response of the airfoil and the changes in the flow field over the entire simulation period can be obtained.

[0093] See appendix Figure 4 , Figure 4 This is a schematic flowchart of the main steps of a fluid-structure interaction numerical simulation according to an embodiment of this application; as shown. Figure 4 As shown, in one embodiment of this application, a CFD solver is used to obtain the aerodynamic information of the airfoil structure, and a CSD solver is used to perform fluid-structure interaction to solve the flutter angular displacement of the airfoil structure.

[0094] Specifically, in the CFD solver, the geometric parameters of the airfoil structure are first defined, and a computational mesh is generated based on the geometric parameters. Then, the unsteady flow field, that is, the fluid flow that changes with time, is solved. Next, the aerodynamic information acting on the structure is determined and sent to the CSD solver.

[0095] In the CSD solver, the structural motion equations are defined, and the structural motion model is obtained based on the structural motion equations. The structural motion model is solved using an iterative method based on the aerodynamic information sent by the CFD solver to obtain the flutter angular displacement response of the airfoil structure, which is then sent to the CFD solver.

[0096] The CFD solver updates the watershed mesh based on the flutter angular displacement response of the airfoil and determines the flutter response of the airfoil after the iteration is complete.

[0097] 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.

[0098] 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.

[0099] Another aspect of this application provides a numerical simulation system for stall flutter of airfoil structures.

[0100] See appendix Figure 5 , Figure 5 This is a schematic diagram of the main structure of a numerical simulation system for stall flutter of an airfoil structure according to an embodiment of this application. Figure 5 As shown, the numerical simulation system for airfoil structure stall flutter in this embodiment includes: a mesh creation module 51, a first acquisition module 52, a second acquisition module 53, a determination module 54, and an update module 55. In some embodiments, one or more of the mesh creation module 51, the first acquisition module 52, the second acquisition module 53, the determination module 54, and the update module 55 can be combined into a single module.

[0101] In some embodiments, the mesh creation module 51 can be configured to acquire the geometric parameters of the airfoil structure, determine the fluid region of the airfoil structure based on the geometric parameters, and generate a flow field mesh based on the fluid region; the first acquisition module 52 can be configured to acquire the aerodynamic information of the airfoil structure at the current moment; the second acquisition module 53 can be configured to acquire the flutter angular displacement of the airfoil structure at the previous moment; the determination module 54 can be configured to determine the flutter angular displacement response of the airfoil structure at the current moment based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement of the airfoil structure at the previous moment; the update module 55 can be configured to update the flow field mesh based on the flutter angular displacement response of the airfoil structure at the current moment. In one embodiment, a description of the specific implementation functions can be found in steps S101 to S105.

[0102] The aforementioned numerical simulation system for airfoil structure stall flutter is used to perform... Figure 1 The numerical simulation method for airfoil stall flutter shown in the examples is similar in its technical principles, the technical problems it solves, and the technical effects it produces. Those skilled in the art can clearly understand this. For the sake of convenience and brevity, the specific working process and related explanations of the numerical simulation system for airfoil stall flutter can be found in the description of the numerical simulation method for airfoil stall flutter, and will not be repeated here.

[0103] Another aspect of this application provides an electronic device.

[0104] See appendix Figure 6 , Figure 6 The illustration exemplarily shows a memory 11 and a processor 12 connected in communication via a bus. In an 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 that, when executed by the at least one processor, implements the methods described in any of the above embodiments. The electronic device described in this application may include driving equipment, intelligent vehicles, robots, and other devices.

[0105] Another aspect of this application provides a computer-readable storage medium.

[0106] In one embodiment of a computer-readable storage medium according to this application, the computer-readable storage medium can be configured to store a program for performing the numerical simulation method for airfoil stall flutter of the above-described method embodiments. This program can be loaded and run by a processor to implement the numerical simulation method for airfoil stall flutter. 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 can 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.

[0107] 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 numerical simulation method for stall flutter of an airfoil structure, characterized in that, The airfoil structure includes an airfoil element and a tuned mass damper, and the method includes: Obtain the geometric parameters of the airfoil structure, determine the fluid region of the airfoil structure based on the geometric parameters, and generate a flow field mesh based on the fluid region; Obtain the aerodynamic information of the airfoil structure at the current moment; Obtain the flutter angular displacement of the airfoil structure at the previous moment; Based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement of the airfoil structure at the previous moment, the flutter angular displacement response of the airfoil structure at the current moment is determined; wherein, determining the flutter angular displacement response of the airfoil structure at the current moment includes: based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement of the airfoil structure at the previous moment, using a pre-constructed structural motion model of the airfoil structure, determining the flutter angular displacement response equation, solving the flutter angular displacement response equation, and obtaining the flutter angular displacement response of the airfoil structure at the current moment; The flow field mesh is updated based on the flutter angular displacement response of the airfoil structure at the current moment.

2. The numerical simulation method for stall flutter of an airfoil structure according to claim 1, characterized in that, The process of obtaining the aerodynamic information of the airfoil structure at the current moment includes: The flow field was numerically simulated using a CFD solver and the unsteady Reynolds time-averaged method to solve the fluid dynamics control equations and determine the physical information of the flow field grid, wherein the physical information of the flow field grid includes the pressure of the flow field grid nodes. The physical information of the flow field grid is post-processed to determine the aerodynamic information of the airfoil structure at the current moment.

3. The numerical simulation method for stall flutter of airfoil structures according to claim 1, characterized in that, The determination of the flutter angular displacement response of the airfoil at the current moment, based on the aerodynamic information of the airfoil at the current moment and the flutter angular displacement of the airfoil at the previous moment, includes: Obtain the pre-constructed structural motion model of the airfoil structure; Based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement of the airfoil structure at the previous moment, the flutter angular displacement response of the airfoil structure at the current moment is determined using the structural motion model of the airfoil structure.

4. The numerical simulation method for stall flutter of airfoil structures according to claim 3, characterized in that, The determination of the flutter angular displacement response of the airfoil at the current moment, based on the aerodynamic information of the airfoil at the previous moment and the flutter angular displacement of the airfoil at the previous moment, using the structural motion model of the airfoil, includes: Based on the flutter angular displacement of the airfoil structure at the previous moment and the structural motion model of the airfoil structure, the flutter angular displacement response equation is determined; Based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement of the airfoil structure at the previous moment, the flutter angular displacement response equation is solved to obtain the flutter angular displacement response of the airfoil structure at the current moment.

5. The numerical simulation method for stall flutter of airfoil structures according to claim 4, characterized in that, The flutter angular displacement response equation is determined based on the flutter angular displacement of the airfoil structure at the previous moment and the structural motion model of the airfoil structure, including: Based on the flutter angular displacement of the airfoil structure at the previous moment, determine the derivative equation corresponding to the flutter angular displacement of the airfoil structure at the current moment; Based on the derivative equation corresponding to the flutter angular displacement of the airfoil at the current moment and the structural motion model of the airfoil, the flutter angular displacement response equation is determined.

6. The numerical simulation method for stall flutter of an airfoil structure according to claim 3, characterized in that, The structural motion model of the airfoil structure is constructed using the following steps: Based on the parameter information of the airfoil structure, the structural motion equation of the airfoil structure is established; Define state variables, and based on the state variables, convert the structural motion equations of the airfoil structure into a structural motion model of the airfoil structure.

7. The numerical simulation method for stall flutter of an airfoil structure according to claim 6, characterized in that, The parameter information of the airfoil structure includes the parameter information of the airfoil components and the parameter information of the tuned mass damper; The process of establishing the structural motion equations of the airfoil structure based on its parameter information includes: Based on the parameter information of the airfoil, the structural motion equation of the airfoil is established; Based on the parameter information of the tuned mass damper and the structural motion equation of the airfoil, the structural motion equation of the airfoil structure is established.

8. A numerical simulation system for stall flutter of an airfoil structure, characterized in that, The airfoil structure includes an airfoil element and a tuned mass damper, and the system includes: The module is used to create a geometric model containing the airfoil structure and the surrounding fluid, set boundary conditions and fluid properties, and generate a flow field mesh based on the fluid region; The first acquisition module is used to acquire the aerodynamic information of the airfoil structure at the current moment; The second acquisition module is used to acquire the flutter angular displacement of the airfoil structure at the previous moment; The determination module is used to determine the flutter angular displacement response of the airfoil structure at the current moment based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement of the airfoil structure at the previous moment; wherein, determining the flutter angular displacement response of the airfoil structure at the current moment includes: based on the aerodynamic information of the airfoil structure at the current moment and the flutter angular displacement of the airfoil structure at the previous moment, using a pre-constructed structural motion model of the airfoil structure, determining the flutter angular displacement response equation, solving the flutter angular displacement response equation, and obtaining the flutter angular displacement response of the airfoil structure at the current moment; An update module is used to update the flow field mesh based on the flutter angular displacement response of the airfoil structure at the current moment.

9. 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 numerical simulation method for airfoil stall flutter according to any one of claims 1 to 7.

10. 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 numerical simulation method for airfoil stall flutter as described in any one of claims 1 to 7.

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