Ceramic matrix composite gas-solid coupling vibration simulation method

Abstract

The invention discloses a gas-solid coupling vibration simulation method for a ceramic-based composite material. The gas-solid coupling vibration simulation method comprises the following steps: establishing a multi-scale finite element model of the ceramic-based material; the load of a gas flow field is calculated through a computational fluid mechanics method, and physical quantities between gas-solid interfaces are accurately mapped and transmitted through a radial basis function interpolation function; stress-strain distribution in the solid domain is solved through a calculation structure dynamics method, closed-loop feedback is formed by combining fluid loads, and bidirectional coupling is conducted on the fluid domain and the solid domain; constructing a loading and unloading stress-strain hysteresis behavior model of the ceramic-based material, and calculating vibration response under any stress path; and the displacement of the solid node is fed back to the CFD fluid model, the position of the fluid node is updated, dynamic gas-solid coupling vibration is calculated, and synchronous iteration in the two domains is kept. According to the method, numerical instability caused by sudden change of material rigidity and nonlinear hysteresis behaviors in traditional numerical simulation is overcome, and the method has calculation efficiency and robustness.

Description

Technical Field

[0001] The present invention relates to the technical field of vibration simulation of ceramic-based materials in a high-temperature flow field environment, and in particular to a gas-solid coupling vibration simulation method for ceramic-based composite materials, which is suitable for dynamic response analysis of ceramic-based structures (such as cantilever beams). Background Art

[0002] Under high temperature environment, the mechanical properties of ceramic matrix composites (CMCs) show significant nonlinearity and are accompanied by complex fluid-structure interaction (FSI). The FSI effect not only affects the vibration behavior of the material, but may also cause structural failure. However, when dealing with the complex nonlinear behavior of CMCs, existing fluid-structure interaction calculation methods often find it difficult to simultaneously ensure accuracy and stability, and it is difficult to provide reliable vibration predictions.

[0003] In existing technologies, such as the staggered iterative coupling technique and the Newmark method, although they can handle fluid-solid coupling problems, most methods use linear material models and ignore the nonlinear behavior of materials during loading and unloading. In existing studies, although fluid-solid coupling models are introduced when calculating the vibration response of ceramic-based materials, there are still the following limitations: (1) Ignoring hysteresis behavior: Most studies are limited to the linear characteristics of materials and fail to effectively describe the nonlinear hysteresis effect, which is crucial in the vibration and fatigue analysis of ceramic-based materials. (2) Poor computational robustness: Traditional methods are prone to cumulative errors in multiple loading and unloading cycles, resulting in unstable numerical calculations and an inability to accurately predict dynamic responses under complex working conditions.

[0004] Ceramic matrix composites (CMCs) are a type of composite material that uses ceramic as a matrix and combines fiber reinforcement materials. They are widely used in the aerospace field because of their excellent properties such as high specific strength, high specific modulus, corrosion resistance, and high temperature resistance. Compared with traditional high-temperature alloys, CMCs not only have a lower density, but also exhibit higher modulus and strength in high-temperature environments, and have stronger resistance to ablation and thermal shock. Therefore, CMCs are considered to be an ideal material to replace high-temperature alloys in the manufacture of hot end components of aircraft engines.

[0005] However, the complex mechanical properties of ceramic matrix composites, such as vibration, fatigue and strength, bring severe performance prediction challenges. Especially in extreme environments such as high temperature, high pressure and gas-solid coupling, materials are often under complex stress conditions and undergo frequent loading and unloading cycles, showing complex variable stiffness and hysteresis behaviors. Therefore, accurately describing the mechanical behavior of these materials under complex working conditions is crucial for their performance prediction in practical applications.

[0006] Current research on the constitutive model of ceramic matrix composites faces two major challenges: (1) Accurate description of damage mode: CMCs are prone to microcracks under high temperature and high pressure environments, and the material exhibits nonlinear characteristics. How to accurately capture the damage mode of the material is a key challenge in constitutive modeling. (2) Nonlinear loading and unloading behavior: Under complex stress conditions, ceramic matrix materials will exhibit significant nonlinear stress-strain hysteresis behavior. Existing modeling methods are often unable to fully cope with this dynamic nonlinear response.

[0007] In order to solve these problems, it is urgent to develop a vibration simulation method that can effectively deal with the variable stiffness and hysteresis behavior of materials, especially in the dynamic response calculation under gas-solid coupling, to ensure the accuracy and stability of the calculation. Summary of the invention

[0008] The present invention aims to solve the deficiency in the prior art that it is difficult to accurately describe complex mechanical behaviors and nonlinear phenomena in the calculation of fluid-solid coupling response of ceramic matrix composites (CMCs) under high temperature and high pressure environments, especially for the variable stiffness and hysteresis behavior of materials under loading and unloading cycles. The present invention proposes a gas-solid coupling vibration simulation method for ceramic matrix composites, which, combined with the dynamic solution model of fluid-solid coupling, provides an efficient and accurate solution for predicting the vibration behavior of ceramic matrix composites.

[0009] In order to achieve the above technical objectives, the technical solution adopted by the present invention is:

[0010] A gas-solid coupling vibration simulation method for a ceramic matrix composite material, the simulation method comprising the following steps:

[0011] S1, based on ceramic matrix composites under high temperature and high pressure environment, comprehensively consider the mechanical properties and thermodynamic characteristics of ceramic matrix composites, and establish a multi-scale finite element model of ceramic matrix materials;

[0012] S2, construct the loading and unloading stress-strain hysteresis behavior model of ceramic-based materials through polynomial fitting method, and calculate the vibration response under arbitrary stress path using explicit dynamic integration method;

[0013] S3, using the computational fluid dynamics (CFD) method to calculate the load of the gas flow field, and through the radial basis function interpolation function, accurately map and transfer the physical quantities between the gas-solid interface to make the dynamic response between the fluid and the solid coordinated;

[0014] S4, solve the stress and strain distribution in the solid domain by the Computational Structural Dynamics (CSD) method, combine the fluid load calculated by CFD to form a closed-loop feedback, and perform bidirectional coupling between the fluid domain and the solid domain;

[0015] S5, feeds back the displacement of the solid node to the CFD fluid model, updates the position of the fluid node, and calculates the dynamic gas-solid coupling vibration to maintain synchronous iteration in the two domains.

[0016] Furthermore, in step S2, the physical quantities at the gas-solid interface include displacement and stress.

[0017] Furthermore, in step S2, the process of accurately mapping and transferring the physical quantity between the gas-solid interface by using the radial basis function interpolation function includes the following steps:

[0018] On the fluid-solid coupling interface, the load of the fluid domain is calculated by CFD to obtain the fluid force on the fluid-solid interface;

[0019] Write a program to map the fluid loads to the nodes of the solid finite element model, and read the displacement of the solid nodes and feed it back to the fluid domain to update the status of the fluid nodes;

[0020] Newton iteration method is used to calculate the mapping between fluid and solid nodes.

[0021] Furthermore, the Newton iteration method is used to perform mapping calculations between fluid and solid nodes, which specifically includes the following steps:

[0022] Using volume spline function As basis functions, the center points x1, x2, …, x N The corresponding values ​​at different positions in the d-dimensional Euclidean space are g1, g2, ..., g N , there exists a continuous function passing through these center points, namely the radial basis function (RBF) interpolation function:

[0023]

[0024] Where: s(x) is the function value that changes with x, x is the coordinates of the unknown point (x, y, z), x i is the coordinate of the center point (x i ,y i ,z i ), is the radial basis function, α i is x i The unknown coefficient at ||xx i|| is the unknown point x and the center point x i The Euclidean distance of , p(x) is a low-order polynomial;

[0025] For conditionally positive basis functions, p(x) is expressed as:

[0026] p(x)=γ0+γ1x+γ2y+γ3z

[0027] The solution condition of the RBF interpolation function is:

[0028] s(x i ) = g i ,i=1,2,…,N

[0029]

[0030] Where: q(x) is a polynomial that satisfies deg(q(x))≤deg(p(x));

[0031] Assume that there are n f and n f nodes, the coordinates of each node are known; use S f and S s They represent the physical quantities of the aerodynamic and structural boundary nodes respectively, and S is used for data transmission. f Come to S s Represented by transferring the matrix H sf or H fs Data interaction between aerodynamics and structure is performed for the above physical quantities; matrix M f and M s represents the radial basis function value between the aerodynamic and structural boundary nodes, Represents two known nodes x i and x j The radial basis function values ​​between them are solved to determine the unknown coefficients α and γ, and the physical quantities are transferred between the grids to ensure the effective coupling and information transfer between the aerodynamic and structural calculation programs;

[0032] Among them, the RBF interpolation function of the aerodynamic boundary is expressed as:

[0033]

[0034] make: γ=[γ0 γ1 γ2 γ3] T ; α=[α1 α2 … α nf ] T ,

[0035] Where: x f1 ~x fnf ,y f1 ~yfnf ,z f1 ~z fnf represents the coordinates of each node on the aerodynamic boundary, (x f1 ,y f1 ,z f1 ) represents the coordinates of the first aerodynamic node, (x fnf ,y fnf ,z fnf ) represents the coordinates of the nfth aerodynamic node; represents the value of the radial basis function between different aerodynamic boundary nodes, represents the radial basis function value of aerodynamic node 1 itself, represents the radial basis function value of the nfth aerodynamic node; S f1 ~S fnf Represents the physical value of each node on the aerodynamic boundary, S f1 is the physical quantity of the first aerodynamic node, S fnf is the physical quantity of the nfth aerodynamic node; nf: represents the total number of nodes on the aerodynamic boundary;

[0036] The RBF interpolation function of the aforementioned aerodynamic boundary is expressed as:

[0037]

[0038] The coefficient matrix to be determined is:

[0039]

[0040] In RBF interpolation, the interpolation function S f It is defined as the weighted sum of various radial basis functions and polynomials to approximate the function value; for the interpolation S of the structure boundary s ,have:

[0041]

[0042] in:

[0043] Substituting the coefficient matrix into the equation:

[0044]

[0045] Right now:

[0046]

[0047] The data transfer matrix from the aerodynamic grid to the structural grid is:

[0048]

[0049] The data transfer matrix from the structural grid to the aerodynamic grid is:

[0050]

[0051] The data transfer matrix is ​​used to exchange data of specific physical quantities at the aerodynamic / structural interface.

[0052] Furthermore, in step S4, the process of constructing a loading and unloading stress-strain hysteresis behavior model of ceramic-based materials by a polynomial fitting method includes:

[0053] S41, loading and unloading experiments are performed on the ceramic-based material to obtain its stress-strain hysteresis loop;

[0054] S42, the multi-scale finite element model is applied to the calculation of stress-strain hysteresis loop to obtain the stress-strain curves under different loading paths;

[0055] S43, extract the stress-strain curve of each loading and unloading process respectively, and use the cubic function to fit the stress σ of the loading section based on the historical maximum strain. + and the stress σ in the unloading section - :

[0056]

[0057] The loading and unloading hysteresis loop is fitted, and the polynomial coefficient a is obtained by interpolation fitting. nu ,a nu , where ε is strain, n = 1, 2, 3, 4;

[0058] Calculate the stress response under arbitrary strain conditions and establish a nonlinear constitutive model that adapts to different working conditions.

[0059] Furthermore, in step S5, the process of reading the dynamic response and updating the fluid node displacement includes the following steps:

[0060] After each time step, the dynamic response including the displacement information of the solid nodes is read; the position of the fluid nodes is updated by feeding the displacement information back to the fluid domain; based on the updated fluid node state, the fluid-solid coupling calculation of the next time step is continued; the above steps are repeated to predict the vibration characteristics of the ceramic matrix composite material under the action of gas-solid coupling.

[0061] Compared with the prior art, the present invention has the following beneficial effects:

[0062] First, the gas-solid coupling vibration simulation method of ceramic-based composite materials of the present invention realizes the efficient transmission of physical quantities in complex fluid-solid coupling environments by introducing RBF interpolation technology, ensuring accurate data exchange between fluid and solid domains. By combining explicit dynamics integration with polynomial fitting, the nonlinear mechanical behavior of ceramic-based materials in high temperature and high pressure environments, especially the variable stiffness and hysteresis effects, is accurately described.

[0063] Second, the gas-solid coupling vibration simulation method of the ceramic-based composite material of the present invention has efficient computing performance and good computing stability, and is suitable for predicting the vibration response of the ceramic-based composite material under complex working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 Schematic diagram of the fluid-solid coupling interface in an embodiment of the present invention.

[0065] Figure 2 Schematic diagram of a radial basis function (RBF) interpolation function in an embodiment of the present invention.

[0066] Figure 3 Schematic diagram of stress-strain curve of loading and unloading hysteresis loop of ceramic-based material in an embodiment of the present invention.

[0067] Figure 4 Schematic diagram of fluid-solid coupling displacement response in an embodiment of the present invention.

[0068] Figure 5 It is a flow chart of the gas-solid coupling vibration simulation method of the ceramic matrix composite material of the present invention. DETAILED DESCRIPTION

[0069] The embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0070] The present invention discloses a gas-solid coupling vibration simulation method for a ceramic matrix composite material, the simulation method comprising the following steps:

[0071] S1, based on ceramic-based composites under high temperature and high pressure environment, a multi-scale finite element model of ceramic-based materials is established by comprehensively considering the mechanical properties and thermodynamic characteristics of ceramic-based composites; the multi-scale finite element model includes micro-scale and macro-scale mechanical models. By combining the two models, the calculation complexity is reduced and the calculation accuracy is improved.

[0072] S2 uses CFD to calculate the load of the gas flow field, and uses the radial basis function (RBF) interpolation function to accurately map and transfer the physical quantities between the gas-solid interface to make the dynamic response between the fluid and the solid coordinated; RBF interpolation technology can perform high-precision data transmission between irregular grids, ensuring the high accuracy of load and displacement transmission at the gas-solid coupling interface.

[0073] S3, the stress and strain distribution in the solid domain is solved by the CSD method, and the fluid load calculated by CFD is combined to form a closed-loop feedback, and the fluid domain and the solid domain are bidirectionally coupled; the fluid load calculated by CFD and the displacement of the solid node in CSD are transmitted to each other to achieve efficient coupling between the fluid and the solid.

[0074] S4, through the polynomial fitting method, constructs the loading and unloading stress-strain hysteresis behavior model of ceramic-based materials, and uses the explicit dynamics integration method to calculate the vibration response under any stress path; polynomial fitting is used to simulate the hysteresis behavior of ceramic-based materials, and the stress-strain characteristics under different stress paths are calculated through the fitted polynomial coefficients. The explicit dynamics integration method is used to solve the vibration response problem of ceramic-based materials under high temperature and high pressure conditions and reduce the numerical divergence caused by the sudden change of material stiffness. Combining explicit dynamics and gas-solid coupling models, it can accurately predict the vibration characteristics of ceramic-based materials in high-temperature flow fields, which is suitable for the calculation of material vibration response in extreme environments.

[0075] S5, feeds back the displacement of the solid node to the CFD fluid model, updates the position of the fluid node, and calculates the dynamic gas-solid coupling vibration to maintain synchronous iteration in the two domains.

[0076] The simulation method of the present invention is described below by taking a ceramic-based cantilever beam as an example. Figure 5 The simulation method of this embodiment specifically includes the following steps:

[0077] Step 1: Establish the finite element model of the ceramic-based cantilever beam

[0078] First, a finite element model of a ceramic-based cantilever beam is established. The model is based on ceramic-based composites under high temperature and high pressure environments, taking into account the mechanical properties of the material and actual working conditions. The meshing in the model is suitable for ceramic-based materials with complex geometries, and appropriate boundary conditions (such as fixed boundary conditions and external loads) are set at both ends of the cantilever beam.

[0079] Figure 1 Schematic diagram of the fluid-solid coupling interface in the embodiment of the present invention. RBF interpolation technology is used for data transmission on the fluid-solid coupling interface. Through the RBF interpolation function, the physical quantities (such as displacement and stress) of the pneumatic domain and the solid domain are accurately mapped and transmitted on the interface to ensure the coordination and consistency of the dynamic response between the fluid and the solid. Figure 2 Schematic diagram of a radial basis function (RBF) interpolation function in an embodiment of the present invention.

[0080] Step 2: Calculate the loading and unloading hysteresis loop and interpolate

[0081] Next, the ceramic-based material was subjected to loading and unloading experiments to obtain its stress-strain hysteresis loop. The finite element model was applied to the calculation of these hysteresis loops to obtain the stress-strain curves under different loading paths. The stress-strain curves of each loading and unloading process were extracted separately, and the loading and unloading sections were fitted with cubic functions based on the historical maximum strain, as described by the following polynomial:

[0082]

[0083] The loading and unloading hysteresis loop is fitted by cubic polynomials and interpolated to calculate the stress response under arbitrary strain conditions. Based on this, a nonlinear constitutive model that adapts to different working conditions is established, which can effectively deal with the variable stiffness and hysteresis behavior of the material. Figure 3 Schematic diagram of stress-strain curve of loading and unloading hysteresis loop of ceramic-based material in an embodiment of the present invention.

[0084] Step 3: Calculate fluid loads based on CFD and implement data mapping

[0085] At the fluid-solid coupling interface, the load of the fluid domain is calculated by CFD to obtain the fluid force on the fluid-solid interface. A program is written to map the fluid load to the nodes of the solid finite element model, and at the same time read the displacement of the solid node and feed it back to the fluid domain to update the state of the fluid node.

[0086] In order to ensure the accuracy of data transfer, the Newton iteration method is used to perform mapping calculations between fluid and solid nodes. In each time step, the fluid domain and the solid domain are synchronized to ensure the accuracy of the dynamic response.

[0087] Using volume spline function As basis functions, if x1,x2,…,x N is a set of central points, which are located at different positions in the d-dimensional Euclidean space. Let the corresponding values ​​of each point be g1, g2, …, g N , which are a set of scalar data. Therefore, there exists a continuous function passing through these center points, namely the RBF interpolation function:

[0088]

[0089] Where: s(x) is the function value that changes with x, x is the coordinates of the unknown point (x, y, z), x i is the coordinate of the center point (x i ,y i ,z i ), is the radial basis function, α i is x i The unknown coefficient at ||xx i|| is the unknown point x and the center point x i The Euclidean distance of , p(x) is a low-order polynomial.

[0090] For conditionally positive basis functions, p(x) can be expressed as:

[0091] p(x)=γ0+γ1x+γ2y+γ3z

[0092] The solution condition of the RBF interpolation function is:

[0093] s(x i ) = g i ,i=1,2,…,N

[0094]

[0095] Where: q(x) is a polynomial that satisfies deg(q(x))≤deg(p(x)).

[0096] Assume that there are points nf and nf on both sides of the aerodynamic and structural interface, and the coordinates of each node are known. f and S s Represents the physical quantities of aerodynamic and structural boundary nodes respectively. Data transfer requires S f Come to S s These physical quantities are expressed by the transfer matrix H sf or H fs Realize data interaction between aerodynamics and structure. Matrix M f and M s represents the radial basis function value between the aerodynamic and structural boundary nodes, and represents the radial basis function value between two known nodes. These matrices form a system of linear equations that allow us to solve the unknown coefficients α and γ, thereby transferring physical quantities between grids and ensuring effective coupling and information transfer between aerodynamic and structural calculation programs.

[0097] The RBF interpolation function of the aerodynamic boundary can be expressed as:

[0098]

[0099] make: γ=[γ0 γ1 γ2 γ3] T ; α=[α1 α2 … α nf ] T

[0100] , then the RBF interpolation function can be expressed as:

[0101]

[0102] Then the undetermined coefficient matrix is:

[0103]

[0104] For the structure boundaries, we have:

[0105]

[0106] in:

[0107] Substituting the coefficient matrix into

[0108]

[0109] Right now

[0110]

[0111] Therefore, the data transfer matrix from the aerodynamic grid to the structural grid is:

[0112]

[0113] Similarly, the data transfer matrix from the structural grid to the aerodynamic grid is:

[0114]

[0115] After obtaining the data transfer matrix, the data exchange of specific physical quantities at the aerodynamic / structural interface can be realized.

[0116] Step 4: Solve the vibration response of the ceramic-based cantilever beam by explicit dynamics integration method

[0117] The vibration response of the ceramic-based cantilever beam is solved by the explicit dynamics integration method, which can handle the nonlinear mechanical behavior of the material during vibration, especially the sudden changes in stress and stiffness.

[0118] Under high temperature and high pressure environment, ceramic-based materials are prone to nonlinear stress-strain behavior. The explicit dynamics integration method can stably solve these complex behaviors and ensure the robustness of the calculation results. The final vibration response results reflect the dynamic characteristics of the ceramic-based cantilever beam under complex working conditions.

[0119] Step 5: Read the dynamic response and update the fluid node displacement

[0120] After each time step, the dynamic response of the solid nodes, especially the displacement information of the nodes, is read. By feeding this displacement information back to the fluid domain, the position of the fluid nodes is updated.

[0121] Based on the updated fluid node state, the fluid-solid coupling calculation of the next time step is continued to ensure the continuity and accuracy of the entire simulation process. Through this cyclic calculation process, the vibration characteristics of the ceramic-based cantilever beam under gas-solid coupling can be accurately predicted. Figure 4 Schematic diagram of fluid-solid coupling displacement response in an embodiment of the present invention.

[0122] The above specific implementation method describes in detail the steps and application scenarios of the ceramic-based cantilever beam vibration calculation method based on RBF gas-solid thermal coupling of the present invention, and demonstrates how to realize the dynamic response calculation of ceramic-based materials in high temperature and high pressure environments through RBF interpolation technology and CFD combined with explicit dynamics integration method.

[0123] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0124] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0125] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0126] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0127] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0128] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A gas-solid coupling vibration simulation method for ceramic matrix composite materials, characterized in that: The simulation method comprises the following steps: S1, based on ceramic matrix composites under high temperature and high pressure environment, comprehensively consider the mechanical properties and thermodynamic characteristics of ceramic matrix composites, and establish a multi-scale finite element model of ceramic matrix materials; S2, construct the loading and unloading stress-strain hysteresis behavior model of ceramic-based materials through polynomial fitting method, and calculate the vibration response under arbitrary stress path using explicit dynamic integration method; S3, using CFD to calculate the load of the gas flow field, and through the radial basis function interpolation function, accurately mapping and transferring the physical quantities between the gas-solid interface, so that the dynamic response between the fluid and the solid is coordinated; S4, solve the stress and strain distribution in the solid domain by CSD method, combine with the fluid load calculated by CFD to form a closed-loop feedback, and perform bidirectional coupling between the fluid domain and the solid domain; S5, feeds back the displacement of the solid node to the CFD fluid model, updates the position of the fluid node, and calculates the dynamic gas-solid coupling vibration to maintain synchronous iteration in the two domains.

2. The ceramic matrix composite gas-solid coupling vibration simulation method according to claim 1, characterized in that: In step S2, the physical quantities at the gas-solid interface include displacement and stress.

3. The gas-solid coupling vibration simulation method of ceramic matrix composite material according to claim 1, characterized in that: In step S2, the process of accurately mapping and transferring the physical quantities between the gas-solid interface by using the radial basis function interpolation function includes the following steps: On the fluid-solid coupling interface, the load of the fluid domain is calculated by CFD to obtain the fluid force on the fluid-solid interface; Write a program to map the fluid loads to the nodes of the solid finite element model, and read the displacement of the solid nodes and feed it back to the fluid domain to update the status of the fluid nodes; Newton iteration method is used to calculate the mapping between fluid and solid nodes.

4. The ceramic matrix composite gas-solid coupling vibration simulation method according to claim 3, characterized in that: The Newton iteration method is used to perform the mapping calculation between the fluid and solid nodes, which specifically includes the following steps: Using volume spline function As basis functions, the center points x1, x2, …, x N The corresponding values ​​at different positions in the d-dimensional Euclidean space are g1, g2, ..., g N , there exists a continuous function passing through these center points, namely the radial basis interpolation function: Where: s(x) is the function value that changes with x, x is the coordinates of the unknown point (x, y, z), x i is the coordinate of the center point (x i ,y i ,z i ), is the radial basis function, α i is x i The unknown coefficient at ||xx i || is the unknown point x and the center point x i The Euclidean distance of , p(x) is a low-order polynomial; For conditionally positive basis functions, p(x) is expressed as: p(x)=γ0+γ1x+γ2y+γ3z The solution condition of the RBF interpolation function is: s(x i )=g i ,i=1,2,…,N Where: q(x) is a polynomial that satisfies deg(q(x))≤deg(p(x)); Assume that there are n f and n f nodes, the coordinates of each node are known; use S f and S s They represent the physical quantities of the aerodynamic and structural boundary nodes respectively, and S is used for data transmission. f Come to S s Representation; by transferring the matrix H sf or H fs Data interaction between aerodynamics and structure is performed for the above physical quantities; matrix M f and M s represents the radial basis function value between the aerodynamic and structural boundary nodes, Represents two known nodes x i and x j The radial basis function values ​​between them are solved to determine the unknown coefficients α and γ, and the physical quantities are transferred between the grids to ensure the effective coupling and information transfer between the aerodynamic and structural calculation programs; Among them, the radial basis interpolation function of the aerodynamic boundary is expressed as: Let: γ = [γ0 γ1 γ2 γ3] T ; α = [α1 α2 … α nf T ,​ Where: (x f1 ,y f1 ,z f1 ) represents the coordinates of the first aerodynamic node, (x fnf ,y fnf ,z fnf ) represents the coordinates of the nfth aerodynamic node; represents the radial basis function value of the first aerodynamic node, represents the radial basis function value of the nfth aerodynamic node; S f1 Represents the physical quantity of the first aerodynamic node, S fnf represents the physical quantity of the nfth aerodynamic node; nf represents the total number of nodes on the aerodynamic boundary; The RBF interpolation function of the aforementioned aerodynamic boundary is expressed as: The coefficient matrix to be determined is: In RBF interpolation, the interpolation function S f It is defined as the weighted sum of various radial basis functions and polynomials, which is used to approximate the function value; the interpolation function S for the structure boundary s ,have: in: Substituting the coefficient matrix into the equation: Right now: The data transfer matrix from the aerodynamic grid to the structural grid is: The data transfer matrix from the structural grid to the aerodynamic grid is: The data transfer matrix is ​​used to exchange data of specific physical quantities at the aerodynamic / structural interface.

5. The gas-solid coupling vibration simulation method of ceramic matrix composite material according to claim 1, characterized in that: In step S4, the process of constructing the loading and unloading stress-strain hysteresis behavior model of the ceramic-based material by a polynomial fitting method includes: S41, loading and unloading experiments are performed on the ceramic-based material to obtain its stress-strain hysteresis loop; S42, the multi-scale finite element model is applied to the calculation of stress-strain hysteresis loop to obtain the stress-strain curves under different loading paths; S43, extract the stress-strain curve of each loading and unloading process respectively, and use the cubic function to fit the stress σ of the loading section based on the historical maximum strain. + and the stress σ in the unloading section - : The loading and unloading hysteresis loop is fitted, and the polynomial coefficient a is obtained by interpolation fitting. nu ,a nd , where ε is strain, n = 1, 2, 3, 4; Calculate the stress response under arbitrary strain conditions and establish a nonlinear constitutive model that adapts to different working conditions.

6. The ceramic matrix composite gas-solid coupling vibration simulation method according to claim 1, characterized in that: In step S5, the process of reading the dynamic response and updating the fluid node displacement includes the following steps: After each time step, the dynamic response including the displacement information of the solid nodes is read; the position of the fluid nodes is updated by feeding the displacement information back to the fluid domain; based on the updated fluid node state, the fluid-solid coupling calculation of the next time step is continued; the above steps are repeated to predict the vibration characteristics of the ceramic matrix composite material under the action of gas-solid coupling.

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