Fiber reinforced-porous mixed structure inverse design device and method

Abstract

The invention provides an inverse design device and method for a fiber reinforced-porous mixed structure, and the device is characterized in that the device comprises a data input module which is used for inputting specified parameters; the data processing module is used for generating variables according to input specified parameters; the design variable optimization module is used for carrying out iterative optimization on the generated variables in combination with the collaborative optimization column formula to obtain the value of a macrostructure design variable, the value of a microstructure design variable and the value of a fiber angle design variable; the system comprises a macro-structure design variable value, a micro-structure design variable value and a fiber angle design variable value, an iteration module used for judging whether the iteration process is finished or not, and a structure generation module used for processing the obtained macro-structure design variable value, the micro-structure design variable value and the fiber angle design variable value to obtain fiber reinforced-porous mixed structure data. According to the fiber reinforced-porous mixed structure inverse design device and method, collaborative optimization design of structures containing isotropic porous materials and anisotropic continuous fiber reinforced materials can be achieved.

Description

Technical Field

[0001] The invention belongs to the field of structural design, and in particular relates to an inverse design device and method for a fiber-reinforced-porous hybrid structure. Background Art

[0002] Nowadays, continuous fiber reinforced composite materials are widely used in the design and manufacturing of high-end equipment structures in major national scientific and technological fields such as aerospace due to their excellent mechanical properties such as specific stiffness and specific strength. In recent years, with the rapid development of additive manufacturing technology, 3D printed continuous fiber reinforced composite structural parts have also begun to be gradually used in engineering due to their advantages such as high manufacturing freedom.

[0003] Fiber-reinforced materials have good specific strength and specific stiffness, but poor shape retention, making it difficult to manufacture fine structures; although matrix materials have low strength and modulus, they have good shape retention. The combination of the two makes it possible to obtain excellent new structures, such as using fiber-reinforced materials to make the main load-bearing components of the structure, and using matrix materials to make porous microstructures to perform functions such as shock absorption.

[0004] Although existing inverse design methods can design fiber-reinforced structures or porous structures, there is still a lack of corresponding inverse design methods for hybrid structures containing both fiber-reinforced materials and porous materials. In addition, existing engineering structure design methods are usually based on the designer's past knowledge and historical data, and the initial design is repeatedly adjusted to ensure that it meets the requirements of use. This process is not only time-consuming and labor-intensive, but in many cases, due to the lack of accurate analysis tools, the final structural form may be too conservative and unable to fully realize the potential of the structure.

[0005] In summary, existing technologies cannot realize the design of fiber-reinforced-porous hybrid structures. Summary of the invention

[0006] The present invention is made to solve the above-mentioned problems, and its purpose is to provide a reverse design device and method for a fiber-reinforced-porous hybrid structure.

[0007] The present invention provides a fiber-reinforced-porous hybrid structure inverse design device, which is used for obtaining the fiber-reinforced-porous hybrid structure of the specified structure according to the boundary conditions required for the specified structure, the initial values ​​of the macro-structure design variables, the initial values ​​of the micro-structure design variables, the initial values ​​of the fiber angle design variables, the size of the macro-structure, the number of macro-units, the number of macro-structure design variables, the volume fraction or mass of the fiber-reinforced material, the number of types of micro-structures, the volume fraction of each micro-structure, the volume fraction of each micro-structure in the macro-structure, the modulus of the fiber-reinforced material in the fiber direction and the direction perpendicular to the fiber, the Poisson's ratio of the fiber-reinforced material, the shear modulus of the fiber-reinforced material, the elastic modulus of the matrix material and the Poisson's ratio of the matrix material. The porous hybrid structure data has the following characteristics, including: a data input module, for a user to input the boundary conditions required for the specified structure, the initial values ​​of the macrostructure design variables, the initial values ​​of the microstructure design variables, the initial values ​​of the fiber angle design variables, the size of the macrostructure, the number of macrounits, the number of macrostructure design variables, the volume fraction or mass of the fiber reinforcement material, the number of microstructure types, the volume fraction of each microstructure, the volume fraction of each microstructure in the macrostructure, the modulus of the fiber reinforcement material in the fiber direction and the perpendicular fiber direction, the Poisson's ratio of the fiber reinforcement material, the shear modulus of the fiber reinforcement material, the elastic modulus of the matrix material and the Poisson's ratio of the matrix material; a data processing module, for The periodic displacement matrix of the microstructure and the displacement vector of the macrostructure are calculated according to the boundary conditions required for the specified structure, the macrostructure design variables, the microstructure design variables, the fiber angle design variables, the size of the macrostructure, the number of macro units, the number of macrostructure design variables, the volume fraction or mass of the fiber reinforcement, the number of types of microstructures, the modulus of the fiber reinforcement in the fiber direction and the perpendicular fiber direction, the Poisson's ratio of the fiber reinforcement, the shear modulus of the fiber reinforcement, the elastic modulus of the matrix material and the Poisson's ratio of the matrix material; the design variable optimization module stores the collaborative optimization column formula for calculating the periodic displacement matrix of the microstructure, the displacement vector of the macrostructure, the volume fraction of each microstructure, The volume fraction of each microstructure in the macrostructure and the collaborative optimization formula are updated, and the values ​​of the macrostructure design variables, the microstructure design variables and the fiber angle design variables are updated; the iteration module stores the preset iteration termination conditions, and is used to judge whether the iteration is completed according to the iteration termination conditions and the values ​​of the macrostructure design variables, the microstructure design variables and the fiber angle design variables. If so, the structure generation module is executed, and if not, the data processing module is executed; the structure generation module is used to process the updated values ​​of the macrostructure design variables, the microstructure design variables and the fiber angle design variables to obtain the specified required fiber reinforced-porous hybrid structure data, wherein the collaborative optimization expression is:

[0008]

[0009] In the formula represents the design variable of the ξ-th material of the ith macroelement, θ i is the design variable representing the i-th fiber angle, represents the design variable of the ξth material of the ith microunit, N M 、N m and N r Respectively represent the number of macro units, the number of microstructure units and the number of microstructure types, is the objective function, represents the volume constraint function of the ξ-th microstructure in the macrostructure, represents the volume constraint of the ξ-th microstructure in the macrostructure, represents the volume constraint function of the ξ-th microstructure; represents the volume constraint of the ξ-th microstructure, R m and R M are the equilibrium equations of the macrostructure and microstructure respectively, δ represents the setting number, D(ρ,θ,γ) represents the elastic interpolation matrix function, the values ​​of the macrostructure design variables include the design variables of all materials of all macro units, and the values ​​of the microstructure design variables include the design variables of all micro units.

[0010] The fiber-reinforced-porous hybrid structure inverse design device provided by the present invention may also have the following characteristics: wherein, in each iteration, the collaborative optimization formula updates the value of the macro design variable and the value of the micro structure design variable through sensitivity, and the expression of the sensitivity of the objective function to the macro structure design variable is: The expression of the sensitivity of the objective function to the microstructure design variables is:

[0011] The fiber-reinforced-porous hybrid structure inverse design device provided by the present invention may also have the following characteristics: wherein the elastic interpolation matrix function D(ρ, θ, γ) at the i-th macro unit is expressed as: In the formula is the equivalent elastic matrix of the ξ-th microstructure, D F is the elastic matrix of the fiber reinforced material, p is the penalty parameter, ρ i is the design variable of the i-th macro unit, θ i Design variable for the ith fiber angle.

[0012] The fiber-reinforced-porous hybrid structure inverse design device provided by the present invention may also have the following characteristics: wherein the macrostructure includes a porous material and a fiber-reinforced material, and the expression of the derivative of the macrostructure design variable of the elastic interpolation matrix function with respect to the porous material is: Where ω=1,2,…,N r , is the equivalent elastic matrix of the ξ-th microstructure, and the expression of the derivative of the elastic interpolation matrix function relative to the macroscopic structural design variables of the fiber-reinforced material is:

[0013] Where p is the penalty parameter, F is the identifier, T represents transposition, and T(θ i ) is the coordinate transformation matrix, which is determined by the fiber placement angle of the macro unit; is the elastic matrix when the fiber direction is 0.

[0014] The fiber-reinforced-porous hybrid structure inverse design device provided by the present invention may also have the following characteristics: wherein the derivative of the elastic interpolation matrix function with respect to the microstructure design variable is expressed as: Where p is the penalty parameter, is the equivalent elastic matrix of the ξ-th microstructure.

[0015] The fiber-reinforced-porous hybrid structure inverse design device provided by the present invention may also have the following characteristics: wherein the elastic matrix D of the fiber-reinforced material F and the i-th fiber angle design variable θ i The expression of the relationship is: Where p is the penalty parameter, F is the identifier, T represents transposition, and T(θ i ) is the coordinate transformation matrix, which is determined by the fiber placement angle of the macro unit, is the Nth macro unit of the ith r +1 design variable, is the elastic matrix when the fiber direction is 0.

[0016] The fiber-reinforced-porous hybrid structure inverse design device provided by the present invention may also have the following characteristics: wherein the expression for the kth iteration update of the i-th fiber angle design variable is: In the formula is the unit vector with angle θ being 0, μ k is the eigenvector at the kth iteration update, |μ k | is the feature vector μ at the kth iteration update k The model, is the design variable of the fiber angle at the kth iteration, and the eigenvector μ at the kth iteration update k The expression is: Where λ1 and λ2 are the two characteristic roots of the characteristic equation. are the eigenvectors corresponding to the two eigenroots, λ1 and λ2 are obtained by solving the characteristic equation, and the characteristic equation expression is: Where σi,xx , σ i,yy , σ i,xy are the stress component in the x direction, the stress component in the y direction, and the shear stress component in the x and y directions of the i-th macro unit, λ is the unknown quantity of the characteristic equation, and the stress component comes from the stress vector σ i , the expression is: i =D(ρ i ,θ i ,γ)ε i , where D(ρ i ,θ i ,γ) represents the elastic interpolation matrix at the i-th macro unit, ε i represents the strain of the i-th macroelement.

[0017] The present invention also provides a fiber-reinforced-porous hybrid structure inverse design method, which is used to obtain the fiber-reinforced-porous hybrid structure data of the specified structure according to the boundary conditions required for the specified structure, the initial values ​​of the macro-structure design variables, the initial values ​​of the micro-structure design variables, the initial values ​​of the fiber angle design variables, the size of the macro-structure, the number of macro-units, the number of macro-structure design variables, the volume fraction or mass of the fiber-reinforced material, the number of micro-structure types, the volume fraction of each micro-structure, the volume fraction of each micro-structure in the macro-structure, the modulus of the fiber-reinforced material in the fiber direction and the perpendicular fiber direction, the Poisson's ratio of the fiber-reinforced material, the shear modulus of the fiber-reinforced material, the elastic modulus of the matrix material and the Poisson's ratio of the matrix material, characterized in that: step S1, according to the boundary conditions required for the specified structure, the macro-structure design variables, the micro-structure design variables, the fiber angle design variables, the size of the macro-structure, the number of macro-units, the number of macro-structure design variables, the volume fraction or mass of the fiber-reinforced material, the micro-structure The number of types, the modulus of the fiber-reinforced material in the fiber direction and the perpendicular fiber direction, the Poisson's ratio of the fiber-reinforced material, the shear modulus of the fiber-reinforced material, the elastic modulus of the matrix material and the Poisson's ratio of the matrix material are used to calculate the periodic displacement matrix of the microstructure and the displacement vector of the macrostructure; step S2, according to the periodic displacement matrix of the microstructure, the displacement vector of the macrostructure, the volume fraction of each microstructure, the volume fraction of each microstructure in the macrostructure and the collaborative optimization column, update the value of the macrostructure design variable, the microstructure design variable and the fiber angle variable; step S3, according to the iteration termination condition and the value of the macrostructure design variable, the value of the microstructure design variable and the fiber angle variable, determine whether the iteration is completed, if so, execute the structure generation module, if not, execute the data processing module; step S4, process the updated value of the macrostructure design variable, the value of the microstructure design variable and the fiber angle variable to obtain the specified required fiber-reinforced-porous hybrid structure data, wherein the expression of the collaborative optimization column is:

[0018]

[0019] In the formula is the design variable representing the ξ-th material of the ith macroelement, θ i is the design variable representing the i-th fiber angle, is the design variable representing the ξth material of the ith microunit, N M 、N m and N r Respectively represent the number of macro units, the number of microstructure units and the number of microstructure types, is the objective function, represents the volume constraint function of the ξ-th microstructure in the macrostructure, represents the volume constraint of the ξ-th microstructure in the macrostructure, represents the volume constraint function of the ξ-th microstructure; represents the volume constraint of the ξ-th microstructure, R m and R M are the equilibrium equations of the macrostructure and microstructure respectively, δ represents the setting number, D(ρ,θ,γ) represents the elastic interpolation matrix function, the values ​​of the macrostructure design variables include all material design variables of all macro units, and the values ​​of the microstructure design variables include the design variables of all micro units.

[0020] Functions and Effects of the Invention

[0021] According to the inverse design device and method of the fiber-reinforced-porous hybrid structure involved in the present invention, because, in the process of updating the values ​​of the design variables using the collaborative optimization formula, the new elastic interpolation matrix introduced can break the boundaries and directions of the isotropic porous material and the anisotropic continuous fiber-reinforced material in the collaborative optimization formula, and realize the collaborative optimization design of the structure containing the isotropic porous material and the anisotropic continuous fiber-reinforced material. Therefore, the inverse design device and method of the fiber-reinforced-porous hybrid structure involved in the present invention can realize the inverse design of the fiber-reinforced-porous hybrid structure, and further expand the application scenarios relative to the single continuous fiber-reinforced material or the porous material. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic diagram of the initial fiber direction in an embodiment of the present invention;

[0023] Figure 2 is a block diagram of a fiber-reinforced-porous hybrid structure reverse design device in an embodiment of the present invention;

[0024] Figure 3 is a material distribution and fiber orientation diagram of a portion of a fiber-reinforced-porous hybrid structure in an embodiment of the present invention;

[0025] Figure 4 is a diagram showing the overall shape of a fiber-reinforced-porous hybrid structure in an embodiment of the present invention;

[0026] Figure 5 It is a schematic flow chart of the reverse design method of the fiber-reinforced-porous hybrid structure in an embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the following embodiments and the accompanying drawings specifically illustrate the device and method for reverse design of partitioned periodic hierarchical structures taking into account material strength of the present invention.

[0028] The invention provides a fiber reinforced-porous hybrid structure inverse design device, which is used to obtain the fiber reinforced-porous hybrid structure data of the specified structure according to the boundary conditions required for the specified structure, the initial values ​​of the macrostructure design variables, the initial values ​​of the microstructure design variables, the initial values ​​of the fiber angle design variables, the size of the macrostructure, the number of macro units and the number of macrostructure design variables, the volume fraction or mass of the fiber reinforcement material, the number of microstructure types, the volume fraction of each microstructure, the volume fraction of each microstructure in the macrostructure, the modulus of the fiber reinforcement material in the fiber direction and the perpendicular fiber direction, the Poisson's ratio of the fiber reinforcement material, the shear modulus of the fiber reinforcement material, the elastic modulus of the matrix material and the Poisson's ratio of the matrix material.

[0029] In this embodiment, the boundary conditions of the required structure are specified as a three-point bending beam, the initial value of the macro design variable is 0.1, the initial value of the microstructure design variable is 0.6, the size of the macro structure is 120mm×25mm, the number of macro units and the number of macro structure design variables are 120×50, the volume fraction of the fiber reinforced material is 20%, the number of microstructure types is 2, the volume fraction of each microstructure is 60%, the volume fraction of each microstructure in the macro structure is 8%, the modulus of the fiber reinforced material in the fiber direction is 40GPa, the modulus in the perpendicular fiber direction is 4GPa, the Poisson's ratio of the fiber reinforced material is 0.33, the shear modulus of the fiber reinforced material is 1.9GPa, the elastic modulus of the matrix material is 4GPa, and the Poisson's ratio of the matrix material is 0.3.

[0030] Figure 1 It is a diagram specifying the initial fiber direction in an embodiment of the present invention.

[0031] Depend on Figure 1 It can be seen that the white segments are fibers. In the initial state, all fibers are set horizontally, that is, in the initial fiber direction, the initial value of the fiber angle design variable is 0.

[0032] This embodiment takes half of the design domain and applies symmetrical boundary conditions at symmetrical positions. In this embodiment, the symmetrical boundary conditions applied at the symmetrical positions are three-point bending beams.

[0033] Figure 2 It is a block diagram of the inverse design device of the fiber-reinforced-porous hybrid structure in an embodiment of the present invention.

[0034] like Figure 2 As shown, the partitioned periodic hierarchical structure inverse design device 100 considering material strength of this embodiment includes a data input module 10, a data processing module 20, a design variable optimization module 30, an iteration module 40 and a structure generation module 50.

[0035] The input module 10 is used for the user to input the boundary conditions required for the specified structure, the initial values ​​of the macrostructure design variables, the initial values ​​of the microstructure design variables, the initial values ​​of the fiber angle design variables, the size of the macrostructure, the number of macro units and the number of macrostructure design variables, the volume fraction or mass of the fiber reinforcement material, the number of microstructure types, the volume fraction of each microstructure, the volume fraction of each microstructure in the macrostructure, the modulus of the fiber reinforcement material in the fiber direction and the perpendicular fiber direction, the Poisson's ratio of the fiber reinforcement material, the shear modulus of the fiber reinforcement material, the elastic modulus of the matrix material and the Poisson's ratio of the matrix material.

[0036] The data processing module 20 is used to obtain the periodic displacement matrix of the microstructure and the displacement vector of the macrostructure according to the boundary conditions required for the specified structure, the macrostructure design variables, the microstructure design variables, the fiber angle design variables, the size of the macrostructure, the number of macro units, the number of macrostructure design variables, the volume fraction or mass of the fiber reinforcement material, the number of types of the microstructure, the modulus of the fiber reinforcement material in the fiber direction and the perpendicular fiber direction, the Poisson's ratio of the fiber reinforcement material, the shear modulus of the fiber reinforcement material, the elastic modulus of the matrix material and the Poisson's ratio of the matrix material. In this embodiment, the data processing module 20 generates the stiffness matrix of the macrostructure, the stiffness matrix of the microstructure, the load vector of the macrostructure and the test load matrix of the microstructure according to the input data, and then calculates the periodic displacement matrix of the microstructure and the displacement vector of the macrostructure according to the above matrices.

[0037] The design variable optimization module 30 stores a collaborative optimization formula, which is used to update the values ​​of the macrostructure design variables, the microstructure design variables and the fiber angle design variables according to the periodic displacement matrix of the microstructure, the displacement vector of the macrostructure, the volume fraction of each microstructure, the volume fraction of each microstructure in the macrostructure and the collaborative optimization formula.

[0038] Among them, the expression of the collaborative optimization column is:

[0039]

[0040] In the formula is the design variable representing the ξ-th material of the ith macroelement, θ i is the design variable representing the i-th fiber angle, is the design variable representing the ξth material of the ith microunit, N M 、N m and N r Respectively represent the number of macro units, the number of microstructure units and the number of microstructure types, is the objective function, represents the volume constraint function of the ξ-th microstructure in the macrostructure, represents the volume constraint of the ξ-th microstructure in the macrostructure, represents the volume constraint function of the ξ-th microstructure; represents the volume constraint of the ξ-th microstructure, R m and R M are the equilibrium equations of the macrostructure and microstructure respectively, δ represents the setting number, D(ρ,θ,γ) represents the elastic interpolation matrix, the macrostructure design variables include the design variables of all materials of all macro units, and the values ​​of the microstructure design variables include the design variables of all micro units.

[0041] In this embodiment, in each iteration, the collaborative optimization formula updates the values ​​of the macro-structure design variables and the values ​​of the micro-structure design variables through sensitivity, as follows:

[0042] The expression of the sensitivity of the objective function to the macrostructural design variables is:

[0043]

[0044] The expression of the sensitivity of the objective function to the microstructure design variables is:

[0045] Among them, the expression of the elastic interpolation matrix D(ρ,θ,γ) at the i-th macro unit is:

[0046]

[0047] In the formula is the equivalent elastic matrix of the ξ-th microstructure, D F is the elastic matrix of the fiber reinforced material, p is the penalty parameter, which is defined as 3 in this column, ρ i is the design variable of all materials of the i-th macro unit, θ i is the design variable for the i-th fiber angle, and isi The amount.

[0048] The macrostructure includes porous materials and fiber-reinforced materials. The expression of the derivative of the macrostructure design variable of the elastic interpolation matrix relative to the porous material is:

[0049]

[0050] Where ω=1,2,…,N r , is the equivalent elastic matrix of the ξ-th microstructure.

[0051] The expression of the derivative of the elastic interpolation matrix with respect to the macroscopic structural design variables of the fiber-reinforced material is:

[0052]

[0053] Where p is the penalty parameter, F is the identifier, T represents transposition, and T(θ i ) is the coordinate transformation matrix, which is determined by the fiber placement angle of the macro unit, is the elastic matrix when the fiber direction is 0.

[0054] The expression of the derivative of the elastic interpolation matrix with respect to the microstructure design variables is:

[0055]

[0056] Where p is the penalty parameter, is the equivalent elastic matrix of the ξ-th microstructure.

[0057] Elastic matrix D of fiber reinforced materials F and the i-th fiber angle design variable θ i The expression of the relationship is:

[0058]

[0059] Where p is the penalty parameter, F is the identifier, T represents transposition, and T(θ i ) is the coordinate transformation matrix, which is determined by the fiber placement angle of the macro unit, is the Nth macro unit of the ith r +1 design variable, is the elastic matrix when the fiber direction is 0.

[0060] The expression for the kth iteration update of the i-th fiber angle design variable is:

[0061]

[0062] In the formula is the unit vector with angle θ being 0, μk , is the feature vector at the kth iteration update, |μ k | is the feature vector μ at the kth iteration update k The model, is the design variable of the fiber angle for the kth iteration.

[0063] The feature vector μ at the kth iteration update k The expression is:

[0064]

[0065] λ1 and λ2 are the two characteristic roots of the characteristic equation. are the eigenvectors corresponding to the two eigenroots. λ1 and λ2 are obtained by solving the characteristic equation, and the characteristic equation expression is:

[0066]

[0067] Where σ i,xx , σ i,yy , σ i,xy are the stress component in the x direction, the stress component in the y direction, and the shear stress component in the x and y directions of the ith macro-element, and λ is the unknown quantity to be solved.

[0068] The stress components are derived from the stress vector σ i , stress vector σ i The expression is:

[0069] σ i =D(ρ i ,θ i ,γ)ε i ,

[0070] Where D(ρ i ,θ i ,γ) represents the elastic interpolation matrix at the i-th macro unit, ε i represents the strain of the i-th macroelement.

[0071] The iteration module 40 stores a preset iteration termination condition, and is used to determine whether the iteration is completed according to the iteration termination condition and the design variables. If so, the structure generation module 50 is executed, and if not, the data processing module 20 is executed.

[0072] The structure generation module 50 is used to process the updated values ​​of the macro-structure design variables, the micro-structure design variables and the fiber angle design variables to obtain the fiber-reinforced-porous hybrid structure data of the specified desired structure.

[0073] The fiber-reinforced-porous hybrid structure data of this embodiment is visualized to obtain the material distribution and fiber direction of the right part of the three-point bending beam.

[0074] Figure 3 Schematic diagram of material distribution and fiber direction of the right side of the three-point bending beam in an embodiment of the present invention.

[0075] like Figure 3 As shown, the designed fiber-reinforced-porous hybrid structure includes two porous materials, namely porous material 1 and porous material 2, and a fiber-reinforced material, and the fiber direction of the fiber-reinforced material is in a random state.

[0076] Symmetrical processing and visualization are performed on the partitioned periodic hierarchical structure data to obtain the visualization results of the three-point bending beam.

[0077] Figure 4 Schematic diagram of a three-point bending beam in an embodiment of the present invention.

[0078] Depend on Figure 4 It can be seen that the structure obtained by using symmetry is the required specified structure, namely the three-point bending beam, and the structural information includes the microstructure part, namely the porous part and the fiber-reinforced material part.

[0079] Figure 5 It is a schematic flow chart of the reverse design method of the fiber-reinforced-porous hybrid structure in an embodiment of the present invention.

[0080] like Figure 5 As shown, the fiber reinforced-porous hybrid structure inverse design method includes the following steps:

[0081] Step S1, using the data processing module 20 to calculate the periodic displacement matrix of the microstructure and the displacement vector of the macrostructure according to the required boundary conditions, macrostructure design variables, microstructure design variables, initial values ​​of fiber angle design variables, size of the macrostructure, number of macro units, number of macrostructure design variables, volume fraction or mass of fiber reinforcement materials, number of types of microstructures, modulus of fiber reinforcement materials in the fiber direction and perpendicular to the fiber direction, Poisson's ratio of fiber reinforcement materials, shear modulus of fiber reinforcement materials, elastic modulus of matrix materials and Poisson's ratio of matrix materials, the periodic displacement matrix of the microstructure and the displacement vector of the macrostructure.

[0082] Step S2, using the design variable optimization module 30 to update the values ​​of the macrostructure design variables, the microstructure design variables and the fiber angle design variables according to the periodic displacement matrix of the microstructure, the displacement vector of the macrostructure, the volume fraction of each microstructure, the volume fraction of each microstructure in the macrostructure and the collaborative optimization formula.

[0083] Step S3, using the iteration module 40 to determine whether the iteration is completed according to the iteration termination condition and the values ​​of the macro-structure design variables, the values ​​of the micro-structure design variables and the values ​​of the fiber angle design variables, if so, execute the structure generation module 50, if not, execute the data processing module 20.

[0084] Step S4, using the structure generation module 50 to process the updated values ​​of the macrostructure design variables, the microstructure design variables and the fiber angle design variables to obtain the fiber-reinforced-porous hybrid structure data of the specified desired structure.

[0085] Functions and Effects of the Embodiments

[0086] According to the inverse design device and method of the fiber-reinforced-porous hybrid structure involved in the embodiment of the present invention, in the process of updating the values ​​of the design variables using the collaborative optimization formula, the new elastic interpolation matrix introduced can break the boundaries and directions of the isotropic porous material and the anisotropic continuous fiber-reinforced material in the collaborative optimization formula, and realize the collaborative optimization design of the structure containing the isotropic porous material and the anisotropic continuous fiber-reinforced material. Therefore, the inverse design device and method of the fiber-reinforced-porous hybrid structure involved in the present invention can realize the inverse design of the fiber-reinforced-porous hybrid structure, and further expand the application scenarios compared with a single continuous fiber-reinforced material or a porous material.

[0087] Furthermore, when designing a hybrid structure, the embodiments of the present invention can use the volume fraction of the fiber-reinforced material, the type of microstructure, the volume fraction of the microstructure, etc. as input characteristics, and can effectively control the amount of continuous fiber-reinforced material and isotropic porous material.

[0088] Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A fiber-reinforced-porous hybrid structure inverse design device, used for obtaining fiber-reinforced-porous hybrid structure data of a specified structure according to the boundary conditions required for the specified structure, the initial values ​​of the macrostructure design variables, the initial values ​​of the microstructure design variables, the initial values ​​of the fiber angle design variables, the size of the macrostructure, the number of macrounits, the number of macrostructure design variables, the volume fraction or mass of the fiber-reinforced material, the number of types of microstructures, the volume fraction of each microstructure, the volume fraction of each microstructure in the macrostructure, the modulus of the fiber-reinforced material in the fiber direction and the perpendicular fiber direction, the Poisson's ratio of the fiber-reinforced material, the shear modulus of the fiber-reinforced material, the elastic modulus of the matrix material and the Poisson's ratio of the matrix material, characterized in that: include: A data input module, for a user to input boundary conditions required for a specified structure, initial values ​​of macrostructure design variables, initial values ​​of microstructure design variables, initial values ​​of fiber angle design variables, size of the macrostructure, number of macrounits, number of macrostructure design variables, volume fraction or mass of fiber reinforcement, number of types of microstructures, volume fraction of each microstructure, volume fraction of each microstructure in the macrostructure, modulus of fiber reinforcement in the fiber direction and perpendicular to the fiber direction, Poisson's ratio of fiber reinforcement, shear modulus of fiber reinforcement, elastic modulus of matrix material and Poisson's ratio of matrix material; A data processing module, for calculating a periodic displacement matrix of a microstructure and a displacement vector of a macrostructure according to the boundary conditions required for the specified structure, the macrostructure design variables, the microstructure design variables, the fiber angle design variables, the size of the macrostructure, the number of macro units, the number of macrostructure design variables, the volume fraction or mass of the fiber reinforcement material, the number of types of the microstructure, the modulus of the fiber reinforcement material in the fiber direction and the perpendicular fiber direction, the Poisson's ratio of the fiber reinforcement material, the shear modulus of the fiber reinforcement material, the elastic modulus of the matrix material and the Poisson's ratio of the matrix material; A design variable optimization module stores a collaborative optimization formula, and updates the value of the macrostructure design variable, the value of the microstructure design variable, and the value of the fiber angle design variable according to the periodic displacement matrix of the microstructure, the displacement vector of the macrostructure, the volume fraction of each microstructure, the volume fraction of each microstructure in the macrostructure, and the collaborative optimization formula; An iteration module stores a preset iteration termination condition, and is used to judge whether the iteration is completed according to the iteration termination condition and the value of the macro-structure design variable, the value of the micro-structure design variable and the value of the fiber angle design variable, and if so, execute the structure generation module, and if not, execute the data processing module; The structure generation module is used to process the updated values ​​of the macrostructure design variables, the microstructure design variables and the fiber angle design variables to obtain the specified fiber-reinforced-porous hybrid structure data. The expression of the collaborative optimization column formula is: In the formula is the design variable representing the ξ-th material of the ith macroelement, θ i is the i-th fiber angle design variable, is the design variable representing the ξth material of the ith microunit, N m 、N m and N r Respectively represent the number of macro units, the number of microstructure units and the number of microstructure types, is the objective function, represents the volume constraint function of the ξ-th microstructure in the macrostructure, represents the volume constraint of the ξ-th microstructure in the macrostructure, represents the volume constraint function of the ξ-th microstructure, represents the volume constraint of the ξ-th microstructure, R m and R M are the equilibrium equations of the macrostructure and microstructure respectively, δ represents the set number, D(ρ,θ,γ) represents the elastic interpolation matrix function, The values ​​of macro-structural design variables include the design variables of all materials of all macro-units, and the values ​​of micro-structural design variables include the design variables of all micro-units.

2. The fiber-reinforced-porous hybrid structure inverse design device according to claim 1, characterized in that: in, In each iteration, the collaborative optimization formula updates the values ​​of the macro-structural design variables and the values ​​of the micro-structural design variables by sensitivity. The expression of the sensitivity of the objective function to the macro-structural design variables is: The expression of the sensitivity of the objective function to the microstructure design variable is:

3. The fiber-reinforced-porous hybrid structure inverse design device according to claim 1, characterized in that: in, The elastic interpolation matrix function D(ρ,θ,γ) at the i-th macro unit is expressed as: In the formula is the equivalent elastic matrix of the ξ-th microstructure, D F is the elastic matrix of the fiber reinforced material, p is the penalty parameter, ρ i is the design variable of all materials of the i-th macro unit, θ i is the design variable for the i-th fiber angle, and is i The amount.

4. The fiber-reinforced-porous hybrid structure inverse design device according to claim 2, characterized in that: in, The macrostructure includes porous material and fiber-reinforced material, The expression of the derivative of the elastic interpolation matrix function with respect to the macroscopic structural design variable of the porous material is: Where ω=1,2,…,N r , is the equivalent elastic matrix of the ξ-th microstructure, The expression of the derivative of the elastic interpolation matrix function with respect to the macroscopic structural design variable of the fiber-reinforced material is: Where p is the penalty parameter, F is the identifier, T represents transposition, and T(θ i ) is the coordinate transformation matrix, which is determined by the fiber placement angle of the macro unit, is the elastic matrix when the fiber direction is 0.

5. The fiber-reinforced-porous hybrid structure inverse design device according to claim 2, characterized in that: in, The expression of the derivative of the elastic interpolation matrix function with respect to the microstructure design variable is: Where p is the penalty parameter, is the equivalent elastic matrix of the ξ-th microstructure.

6. The fiber-reinforced-porous hybrid structure inverse design device according to claim 3, characterized in that: in, The elastic matrix D of the fiber reinforced material F The i-th fiber angle design variable θ i The expression of the relationship is: Where p is the penalty parameter, F is the identifier, T represents transposition, and T(θ i ) is the coordinate transformation matrix, which is determined by the fiber placement angle of the macro unit, is the Nth macro unit of the ith r +1 design variable, is the elastic matrix when the fiber direction is 0.

7. The fiber-reinforced-porous hybrid structure inverse design device according to claim 1, characterized in that: in, The expression for the kth iteration update of the i-th fiber angle design variable is: In the formula is the unit vector with angle θ being 0, μ k is the eigenvector at the kth iteration update, |μ k | is the feature vector μ during the k-th iteration update k The model, is the design variable of the fiber angle at the kth iteration, The feature vector μ during the k-th iteration update k The expression is: Where λ1 and λ2 are the two characteristic roots of the characteristic equation. are the eigenvectors corresponding to the two eigenroots. Said λ1 and λ2 are obtained by solving the characteristic equation, and the characteristic equation expression is: Where σ i,xx , σ i,yy , σ i,xy are the stress component in the x direction, stress component in the y direction and shear stress component of the i-th macro unit, respectively, and λ is the unknown quantity to be solved. The stress components are derived from the stress vector σ i , the stress vector σ i The expression of σ is: i =D(ρ i ,θ i ,γ)ε i , Where D(ρ i ,θ i ,γ) represents the elastic interpolation matrix at the i-th macro unit, ε i represents the strain of the i-th macroelement.

8. A fiber-reinforced-porous hybrid structure inverse design method, used to obtain fiber-reinforced-porous hybrid structure data of a specified structure according to the boundary conditions required for the specified structure, the initial values ​​of the macrostructure design variables, the initial values ​​of the microstructure design variables, the initial values ​​of the fiber angle design variables, the size of the macrostructure, the number of macrounits, the number of macrostructure design variables, the volume fraction or mass of the fiber reinforcement material, the number of microstructure types, the volume fraction of each microstructure, the volume fraction of each microstructure in the macrostructure, the modulus of the fiber reinforcement material in the fiber direction and the perpendicular fiber direction, the Poisson's ratio of the fiber reinforcement material, the shear modulus of the fiber reinforcement material, the elastic modulus of the matrix material and the Poisson's ratio of the matrix material, characterized in that: Step S1, calculating the periodic displacement matrix of the microstructure and the displacement vector of the macrostructure according to the boundary conditions required for the specified structure, the macrostructure design variables, the microstructure design variables, the fiber angle design variables, the size of the macrostructure, the number of macro units, the number of macrostructure design variables, the volume fraction or mass of the fiber reinforcement, the number of types of the microstructure, the modulus of the fiber reinforcement in the fiber direction and the perpendicular fiber direction, the Poisson's ratio of the fiber reinforcement, the shear modulus of the fiber reinforcement, the elastic modulus of the matrix material and the Poisson's ratio of the matrix material; Step S2, updating the values ​​of the macrostructure design variables and the microstructure design variables according to the periodic displacement matrix of the microstructure, the displacement vector of the macrostructure, the volume fraction of each microstructure, the volume fraction of each microstructure in the macrostructure and the collaborative optimization formula; Step S3, judging whether the iteration is completed according to the iteration termination condition and the value of the macro-structure design variable and the value of the micro-structure design variable, if so, executing the structure generation module, if not, executing the data processing module; Step S4, processing the updated values ​​of the macro-structure design variables and the micro-structure design variables to obtain the specified fiber-reinforced-porous hybrid structure data, The expression of the collaborative optimization column formula is: In the formula is the design variable representing the ξ-th material of the ith macroelement, θ i is the design variable representing the i-th fiber angle, is the design variable representing the ξth material of the ith microunit, N M 、N m and N r Respectively represent the number of macro units, the number of microstructure units and the type of microstructure, is the objective function, represents the volume constraint function of the ξ-th microstructure in the macrostructure, represents the volume constraint of the ξ-th microstructure in the macrostructure, represents the volume constraint function of the ξ-th microstructure; represents the volume constraint of the ξ-th microstructure, R m and R M are the equilibrium equations of the macrostructure and microstructure respectively, δ represents the set number, D(ρ,θ,γ) represents the elastic interpolation matrix function, The values ​​of macro-structural design variables include the design variables of all materials of all macro-units, and the values ​​of micro-structural design variables include the design variables of all micro-units.

Images