Time-domain full-wave calculation method for electrical performance of radome under thermal-mechanical-electrical coupling

Abstract

The invention discloses a time-domain full-wave calculation method for the electrical performance of a radome under thermal-mechanical-electrical coupling, and relates to the technical field of radomes. The method comprises the following steps: creating a finite element mesh model for radome thermodynamic calculation; transient thermal calculation is carried out, and an antenna housing response temperature field under the thermal load effect is obtained; static force calculation is carried out, and a radome structure deformation field under the action of heat and force loads is obtained; based on the initial finite element mesh model and the structural deformation field, obtaining a deformed radome mesh model; dividing a deformed antenna housing electromagnetic computational domain by adopting a Yee grid; in combination with the dielectric temperature excursion characteristic of the material, mapping to obtain an electromagnetic parameter of each Yee grid; and calculating the electrical performance of the antenna housing by adopting a finite difference time domain method in combination with boundary conditions. The problem that dielectric temperature excursion and structural deformation information of a radome body material caused by a thermal load are accurately transmitted to an electric simulation model of the radome is solved, and high-precision time-domain full-wave numerical calculation of the electric performance of the radome under thermal-mechanical-electric three-field coupling is realized.

Description

Technical Field

[0001] This document belongs to the field of antenna cover technology, and specifically relates to a time-domain full-wave numerical calculation method for the electrical performance of antenna covers under thermal-mechanical-electrical coupling. Background Art

[0002] The radome is a protective shell used to protect the radar antenna from external extreme environmental loads and to ensure the normal transmission of electromagnetic waves. In practical applications, electromagnetic waves passing through the radome will experience a certain amount of energy attenuation and phase delay, which will change the original electromagnetic radiation characteristics of the antenna and affect the detection distance, target pointing accuracy and anti-interference ability of the internal radar. The electrical performance of the radome mainly includes power transmission coefficient, aiming error and slope, sidelobe lift, etc. These performance parameters are obtained by comparing the radiation far-field pattern of the antenna with and without the radome.

[0003] At present, the development of aircraft is changing with each passing day, and their functions are becoming increasingly powerful. In order to improve their penetration and strike capabilities, they are constantly pursuing higher flight speeds and longer flight distances. The radome of high-speed aircraft has to withstand severe aerodynamic heat, aerodynamic force and inertial loads, and its materials and structures must be carefully selected and designed. Under high-speed flight conditions, the radome is heated, causing dielectric temperature drift, thermal expansion, and force deformation of the material, which will change its original electromagnetic properties, causing its electrical properties such as power transmission coefficient and aiming error to deviate from the original design values, thereby affecting the radar detection performance.

[0004] In order to ensure the consistency of the electrical performance design of the radome between the sky and the earth, it is necessary to carry out the multi-physics coupling design of heat, force and electricity to accurately calculate the influence of dielectric temperature drift and structural deformation on the electrical performance of the radome. At present, due to the limitations of testing technology, it is very difficult to test the electrical performance of the radome under thermal and mechanical loads. The development of numerical simulation technology is an effective and feasible way to analyze and evaluate the electrical performance of the radome under high-speed flight conditions.

[0005] The numerical simulation calculation methods for the electrical performance of the radome are mainly divided into two categories: high-frequency approximation method and full-wave method. The high-frequency approximation method adopts the optical approximation theory, which has a fast calculation speed but low accuracy and is difficult to adapt to complex structures. Compared with the high-frequency approximation method, the full-wave method has relatively low calculation efficiency, but has higher calculation accuracy and can adapt to complex structures well. Currently, with the development of computer technology, computing power has been greatly improved, and the application of full-wave calculation methods for electrical performance has become more and more extensive. The full-wave calculation methods mainly include the finite element method, the method of moments, and the finite difference time domain method. Among them, the finite element method and the method of moments belong to the frequency domain method. Their one-time solution can only obtain the response at a single frequency point, and are mostly used for narrowband problems;

[0006] In the numerical calculation process of the electrical performance of the radome of a high-speed aircraft, how to effectively characterize the influence of thermal and mechanical loads is the key to accurately calculating the electrical performance of the radome under high-speed flight conditions. The difficulty lies in how to efficiently and accurately transfer the dielectric temperature drift of the radome cover material and the deformation of the cover structure caused by thermal loads to the electrical simulation model of the radome. Summary of the invention

[0007] The purpose of this specification is to provide a numerical calculation method for the electrical performance of the radome under thermal-mechanical-electrical coupling based on the time-domain finite difference method, which solves the problem of accurately transmitting the dielectric temperature drift and structural deformation information of the radome body material caused by thermal loads to the electrical simulation model of the radome.

[0008] To achieve the above purpose, the technical solutions provided in this specification are as follows:

[0009] In a first aspect, this specification provides a time-domain full-wave calculation method for the electrical performance of a radome under thermal-mechanical-electrical coupling, comprising:

[0010] Create a finite element mesh model for radome thermal calculations;

[0011] Carry out transient thermal calculation to obtain the temperature field of the radome response under thermal load;

[0012] Conduct static calculations to obtain the deformation field of the radome structure under thermal and mechanical loads;

[0013] Based on the initial finite element mesh model and the structural deformation field, the mesh model of the deformed radome is obtained;

[0014] Use Yee meshing to divide the electromagnetic calculation domain of the deformed radome;

[0015] Combined with the dielectric temperature drift characteristics of the material, the electromagnetic parameters of each Yee grid are mapped and obtained;

[0016] The finite-difference time-domain method is used to calculate the electrical properties of the radome.

[0017] In the second aspect, the present specification provides a time-domain full-wave calculation device for the electrical performance of a radome under thermal-mechanical-electrical coupling, including: a finite element mesh model creation module, a temperature field determination module, a structural deformation field determination module, a deformed radome mesh model determination module, an electromagnetic mesh division module, an electromagnetic parameter acquisition module, and a radome electrical performance calculation module, wherein:

[0018] The finite element mesh model creation module is used to create a finite element mesh model for thermal calculation of the radome;

[0019] The temperature field determination module is used to carry out transient thermal calculations to obtain the radome response temperature field under the action of thermal loads;

[0020] The structural deformation field determination module is used to carry out static calculations to obtain the deformation field of the radome structure under the action of thermal and mechanical loads;

[0021] The deformed radome mesh model determination module is used to obtain the deformed radome mesh model based on the initial finite element mesh model and the structural deformation field;

[0022] The electromagnetic meshing module is used to divide the electromagnetic calculation domain of the deformed radome using Yee meshing;

[0023] The electromagnetic parameter acquisition module is used to map and obtain the electromagnetic parameters of each Yee grid in combination with the dielectric temperature drift characteristics of the material;

[0024] The antenna cover electrical performance calculation module is used to calculate the antenna cover electrical performance by using the finite difference time domain method.

[0025] The beneficial effects of the present invention are as follows:

[0026] This specification discloses a time-domain full-wave calculation method for the electrical performance of a radome under thermal-mechanical-electrical coupling. The method creates a finite element mesh model for thermal calculation of the radome; performs transient thermal calculation to obtain the radome response temperature field under thermal load; performs static calculation to obtain the radome structural deformation field under thermal and mechanical loads; obtains a deformed radome mesh model based on the initial finite element mesh model and the structural deformation field; uses Yee meshing to divide the electromagnetic calculation domain of the deformed radome; combines the dielectric temperature drift characteristics of the material to map and obtain the electromagnetic parameters of each Yee mesh; combines the boundary conditions to calculate the electrical performance of the radome using the time-domain finite difference method. This method can obtain an ultra-wideband response in one solution, and has the advantages of direct time-domain solution, strong robustness, no need for matrix inversion, easy processing of complex multi-media structures, and natural parallelism. It is particularly suitable for the calculation of wide-band electrical performance of electrically large-sized radomes. This method realizes high-precision time-domain full-wave numerical calculation of the electrical performance of the radome under thermal-mechanical-electrical three-field coupling, which can effectively ensure the consistency of the electrical performance design of the radome of high-speed aircraft in the sky and the earth. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of a time-domain full-wave calculation method for the electrical performance of a radome under thermal-mechanical-electrical coupling provided in an embodiment of this specification;

[0028] Figure 2 It is a schematic diagram of a calculation process of the electrical performance of a radome under thermal-mechanical-electrical coupling provided in an embodiment of this specification;

[0029] Figure 3 is a schematic diagram of a finite element mesh model of a radome based on tetrahedral unit division provided in an embodiment of this specification;

[0030] Figure 4 is a schematic diagram of a radome response temperature field provided in an embodiment of this specification;

[0031] Figure 5 It is a schematic diagram of a radome deformation field and a finite element mesh model generation after deformation provided in an embodiment of this specification;

[0032] Figure 6 It is a schematic diagram of dividing the electromagnetic calculation domain by a Yee grid provided in the embodiments of this specification;

[0033] Figure 7 is a schematic diagram of a dielectric temperature drift characteristic curve of a cover material provided in an embodiment of this specification;

[0034] Figure 8 It is a schematic diagram of the electromagnetic parameter position of a Yee cell and its spatial relationship with a finite element unit provided in an embodiment of this specification;

[0035] Fig. 9 is a schematic diagram of the effect of a radome on an antenna radiation pattern at a typical moment under a flight condition provided in an embodiment of this specification;

[0036] Fig.10 It is a schematic diagram of a time-domain full-wave calculation device for the electrical performance of a radome under thermal-mechanical-electrical coupling provided in an embodiment of this specification. DETAILED DESCRIPTION

[0037] In order to solve the problem that the existing technology is difficult to consider in high-precision calculation the impact of the force deformation of the cover body and the dielectric temperature drift of the material induced by the temperature field on the electrical performance of the antenna cover during high-speed flight, an embodiment of the present invention provides a full-wave numerical calculation method for the electrical performance of the antenna cover under the coupling of thermal, mechanical and electric fields.

[0038] The terms "first", "second", etc. in the description and claims of the embodiments of the present invention and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein.

[0039] The "multiple or several" mentioned in this article refers to two or more. "And / or" describes the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects are in an "or" relationship.

[0040] The preferred embodiments of the present invention are described below in conjunction with the drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention. In addition, the embodiments of the present invention and the features in the embodiments may be combined with each other if there is no conflict. Specific embodiment one:

[0042] The present embodiment specifically relates to a method for high-precision calculation of the electrical performance of a high-speed aircraft radome under a severe external thermal load environment.

[0043] First of all, it should be noted that the numerical simulation calculation methods for the electrical performance of the radome are mainly divided into two categories: high-frequency approximation method and full-wave method. The high-frequency approximation method adopts the optical approximation theory, which has a fast calculation speed but low accuracy and is difficult to adapt to complex structures. Compared with the high-frequency approximation method, the full-wave method has relatively low calculation efficiency, but has higher calculation accuracy and can adapt to complex structures well. The full-wave calculation methods mainly include finite element method, moment method and finite difference time domain method. Among them, finite element method and moment method belong to frequency domain methods. Their one-time solution can only obtain the response at a single frequency point and are mostly used for narrowband problems.

[0044] The finite-difference time-domain method used in this embodiment belongs to the time domain method, which can obtain ultra-wideband response in one solution. It has the advantages of direct time domain solution, strong robustness, no need for matrix inversion, easy processing of complex multi-media structures, and natural parallelism. It is especially suitable for the calculation of wide-band electrical performance of electrically large-sized antenna covers.

[0045] like Figure 1 , Figure 2 As shown, a time-domain full-wave calculation method for the electrical performance of a radome under thermal-mechanical-electrical coupling of this embodiment;

[0046] The method provided in this embodiment specifically includes the following steps:

[0047] It should be noted that before step 102, the following steps are included:

[0048] S101. Determine through experiments how the physical properties of the radome material change with temperature;

[0049] The above-mentioned physical properties of the radome material may also be obtained through other means.

[0050] The above-mentioned physical properties of the radome material include: relative dielectric constant, loss tangent, thermal conductivity, specific heat capacity, thermal expansion coefficient, elastic modulus, Poisson's ratio and density.

[0051] Step 102, creating a finite element mesh model for thermal calculation of the radome;

[0052] Specifically, in step 102, the finite element mesh modeling module of ANSYS Multiphysics can be selected to create a finite element mesh model for thermal calculation of the radome, such as Figure 3 As shown;

[0053] The finite element mesh model used for thermal calculation of the radome includes: mesh division using tetrahedral units, the size of the tetrahedral units is determined by the accuracy requirements of the thermodynamic simulation calculation, and the size is generally larger than the mesh size required for electromagnetic simulation;

[0054] In the specific implementation, the finite element mesh modeling module of ANSYS Multiphysics can be used to create a finite element mesh model for the thermal calculation of the radome, such as Figure 3 shown.

[0055] Step 104, performing transient thermal calculation to obtain the radome response temperature field under the action of thermal load;

[0056] The heat load is: the cold wall heat flux, recovery enthalpy and pressure that vary with time; or the hot wall heat flux that varies with time; or the temperature that varies with time.

[0057] Specifically, in step 104, the transient thermal calculation includes:

[0058] Based on the finite element mesh model, the finite element method is used to solve the three-dimensional transient heat conduction equation in the Cartesian coordinate system:

[0059]

[0060] Where ρ is density, c is specific heat, t is time, T is unit node temperature, λ is thermal conductivity, and x, y, z are grid unit node coordinates.

[0061] In one embodiment, the transient thermal analysis module of ANSYS Multiphysics can be used to perform transient thermal calculation on the finite element mesh model of the radome to obtain the transient temperature field of the radome under the external thermal load, such as Figure 4 shown.

[0062] Step 106, perform static calculation to obtain the deformation field of the radome structure under the action of thermal and mechanical loads;

[0063] Specifically, in step 106, according to the force load condition of the radome in high-speed flight and the temperature field calculated in step 102, the static analysis module of ANSYS Multiphysics can be selected to perform static analysis on the finite element mesh model of the radome to obtain the deformation field of the radome structure under the action of thermal and force loads;

[0064] Wherein, the force load is pneumatic pressure and inertia load.

[0065] The static force calculation is as follows: based on the finite element mesh model, the finite element method is used to solve the structural thermoelastic equation in the Cartesian coordinate system:

[0066]

[0067] In the formula, σ x , σ y , σ z are the normal stresses in the x, y, and z directions, ε x , ε y , ε z are the normal strains in the x, y, and z directions, τ xy , τ yz , τ xz are the shear stresses in the xy, yz, and xz planes, respectively, xy , γ yz , γ xz are the shear strains in the xy, yz, and xz planes respectively. , E is the elastic modulus, G is the shear modulus, ν is the Poisson's ratio, and α is the thermal expansion coefficient.

[0068] Step 108: obtaining a deformed radome mesh model based on the initial finite element mesh model and the structural deformation field;

[0069] Specifically, a specific implementation of step 108 may be:

[0070] The deformation variables of the unit nodes of the initial finite element mesh model of the radome are superimposed to obtain the deformed finite element mesh model, such as Figure 5 As shown; thus accurately characterizing the structural dimensions of the radome under flight conditions; the node coordinates of the finite element mesh unit of the radome after deformation can be expressed as:

[0071] (x t ,y t ,z t )=(x0+u,y0+v,z0+w) (3)

[0072] In the formula, x t ,y t , z t is the unit node coordinate after deformation, x0, y0, z0 are the unit node coordinates before deformation, u, v, w are the deformation variables of the unit node in the x, y, z directions respectively;

[0073] Step 110, using Yee meshing to divide the electromagnetic calculation domain of the deformed radome;

[0074] Specifically, a specific implementation of step 110 may be:

[0075] According to the finite element mesh model of the deformed radome, the electromagnetic calculation domain is determined and divided using the Yee mesh to obtain the electromagnetic simulation mesh;

[0076] like Figure 6 As shown, the size of the Yee cell is determined by the calculation frequency and the electromagnetic properties of the target object, and is generally no larger than 1 / 12 of the wavelength of the cover material medium;

[0077] The dimensions of the Yee cell in the x, y, and z coordinate directions are Δx, Δy, and Δz respectively, and the time discrete interval is Δt. The actual position coordinates of the field component and the mark (i, j, k) have the following corresponding relationship:

[0078] Table 1 Relationship between the actual coordinates of the field components in the Yee cell and the discrete markers (i, j, k)

[0079]

[0080]

[0081] Step 112, mapping and obtaining electromagnetic parameters of each Yee grid in combination with the dielectric temperature drift characteristics of the material;

[0082] Among them, the dielectric temperature drift characteristics of the material are that the electromagnetic properties of the cover material usually change with temperature, which is mainly manifested in that the dielectric constant and conductivity (loss tangent) change with temperature, which can be obtained through high-temperature performance testing of the material. According to the test data, the temperature variation function of the electromagnetic properties can be fitted: the dielectric constant temperature variation function ε(T), the conductivity temperature variation function σ(T) (or the loss tangent temperature variation function tanδ(T)), such as Figure 7 As shown;

[0083] Specifically, a specific implementation of step 112 may be:

[0084] Based on the temperature variation function of the electromagnetic properties of the material, the temperature variation electromagnetic parameters on each Yee cell are obtained by interpolating the temperature field of the finite element unit after deformation, and then the electromagnetic simulation model is obtained;

[0085] Specifically, the mapping obtains the electromagnetic parameters of each Yee grid, including:

[0086] Based on the temperature variation function of the electromagnetic properties of the material, the temperature variation electromagnetic parameters on each Yee cell are obtained by interpolating the temperature field of the finite element unit after deformation, and the relative dielectric constant ε at a certain position P is used. x Take (i,j,k) as an example, it is in a finite element tetrahedron unit, such as Figure 8 As shown, its value can be calculated by formula (4):

[0087]

[0088] Wherein, v1, v2, v3, and v4 are the volume coordinates of point P in the volume coordinate system of the tetrahedral unit, T1, T2, T3, and T4 are the temperatures of the four nodes of the tetrahedral unit respectively, and T is the temperature of point P.

[0089] Step 114: Calculate the electrical performance of the radome using a finite difference time domain method.

[0090] Specifically, a specific implementation of step 114 may be:

[0091] Based on the electromagnetic simulation model discretized by Yee grid, the second-order central difference format of discrete electromagnetic field quantities is used to approximate the first-order partial differentials of continuous electromagnetic field quantities with respect to space and time. The update formula of each electromagnetic field component is derived, and then the solution of the electromagnetic calculation domain can be iteratively calculated in combination with the boundary conditions.

[0092] Furthermore, the calculation of electrical performance using the finite difference time domain method includes:

[0093] Based on Yee grid discretization, the discrete electromagnetic field quantity second-order central difference format is used to approximate the first-order partial differential of the continuous electromagnetic field quantity with respect to space and time, and then the update formula of each electromagnetic field component is derived. x (E x As an example, the update formula is:

[0094]

[0095] In the formula, J ix is the current density load, the electromagnetic calculation coefficient C exe , C exhz , C exhy , C exj Determined by electromagnetic parameters, it varies in space, and its calculation expression is:

[0096]

[0097] Similarly, get E y、 E z , H x H y , H z Updated formulas for the electromagnetic field components.

[0098] Based on the field quantity update formula and combined with the boundary conditions, the solution of the electromagnetic calculation domain can be iteratively calculated, that is, the spatial distribution of the electromagnetic field can be obtained. The comparison of the far-field radiation patterns of the antenna with and without a cover under high-speed flight conditions is shown in Figure 2. Fig. 9 shown.

[0099] In summary, this embodiment creates a finite element mesh model for thermal calculation of the radome; performs transient thermal calculation to obtain the radome response temperature field under thermal load; performs static calculation to obtain the radome structural deformation field under thermal and force loads; obtains the deformed radome mesh model based on the initial finite element mesh model and the structural deformation field; uses Yee mesh to divide the electromagnetic calculation domain of the deformed radome; combines the dielectric temperature drift characteristics of the material to map and obtain the electromagnetic parameters of each Yee mesh; combines the boundary conditions to calculate the electrical performance of the radome using the time domain finite difference method. This solves the problem of accurately transmitting the dielectric temperature drift and structural deformation information of the radome body material caused by thermal loads to the electrical simulation model of the radome, and realizes the high-precision time domain full-wave numerical calculation of the electrical performance of the radome under the coupling of the thermal, mechanical and electrical fields, which can effectively ensure the consistency of the electrical performance design of the radome of high-speed aircraft in the sky and the earth. Specific embodiment 2:

[0101] This embodiment provides a time-domain full-wave calculation device for the electrical performance of a radome under thermal-mechanical-electrical coupling. Fig.10 , including: a finite element mesh model creation module 1001, a temperature field determination module 1002, a structural deformation field determination module 1003, a deformed radome mesh model determination module 1004, an electromagnetic mesh division module 1005, an electromagnetic parameter acquisition module 1006, and a radome electrical performance calculation module 1007, wherein:

[0102] The finite element mesh model creation module 1001 is used to create a finite element mesh model for thermal calculation of the radome;

[0103] The temperature field determination module 1002 is used to perform transient thermal calculations to obtain the radome response temperature field under the action of thermal loads;

[0104] The structural deformation field determination module 1003 is used to perform static calculations to obtain the deformation field of the radome structure under the action of thermal and mechanical loads;

[0105] The deformed radome mesh model determination module 1004 is used to obtain the deformed radome mesh model based on the initial finite element mesh model and the structural deformation field;

[0106] The electromagnetic meshing module 1005 is used to use Yee meshing to divide the electromagnetic calculation domain of the deformed radome;

[0107] The electromagnetic parameter acquisition module 1006 is used to map and obtain the electromagnetic parameters of each Yee grid in combination with the dielectric temperature drift characteristics of the material;

[0108] The antenna cover electrical performance calculation module 1007 is used to calculate the antenna cover electrical performance by using the finite difference time domain method.

[0109] Optionally, the finite element mesh model includes: meshing using tetrahedral units, the size of the tetrahedral units is determined by the accuracy requirements of thermodynamic simulation calculations, and the size is generally larger than the size required for electromagnetic simulation.

[0110] Optionally, the conditions of the heat load are: cold wall heat flux, recovery enthalpy and pressure that vary with time; hot wall heat flux that varies with time; or temperature that varies with time.

[0111] Optionally, the force load conditions are pneumatic pressure and inertia load.

[0112] Optionally, the deformed radome mesh model determining module 1004 is specifically used to:

[0113] The deformation variables of the unit nodes of the initial finite element mesh model of the radome are superimposed on the deformation variables to obtain the deformed finite element mesh model, thereby determining the structural dimensions of the radome under flight conditions.

[0114] Optionally, the electromagnetic grid division module 1005 is specifically used to:

[0115] According to the finite element mesh model of the deformed radome, the electromagnetic calculation domain is determined and divided using the Yee mesh;

[0116] The size of the Yee cell is determined by the calculation frequency and the electromagnetic properties of the target object, and is generally no larger than 1 / 12 of the wavelength of the cover material medium.

[0117] Optionally, the dielectric temperature drift characteristics of the material include:

[0118] The electromagnetic properties of the cover material usually vary with temperature;

[0119] The electromagnetic properties of the cover material are obtained through high-temperature performance testing of the material. The temperature variation functions of the electromagnetic properties of the material include: the temperature variation function of the dielectric constant ε(T) and the temperature variation function of the conductivity σ(T).

[0120] Optionally, the electromagnetic parameter acquisition module 1006 is specifically used to:

[0121] Based on the temperature variation function of the electromagnetic properties of the material, the temperature variation electromagnetic parameters on each Yee cell are obtained by interpolating the temperature field of the finite element unit after deformation.

[0122] Optionally, the antenna cover electrical performance calculation module 1007 is specifically used to:

[0123] Based on Yee grid discretization, the second-order central difference format of discrete electromagnetic field quantities is used to approximate the first-order partial differentials of continuous electromagnetic field quantities with respect to space and time. The update formulas of each electromagnetic field component are derived. Combined with the boundary conditions, the solution of the electromagnetic calculation domain is iteratively calculated.

[0124] In summary, this embodiment creates a finite element mesh model for thermal calculation of the radome; performs transient thermal calculation to obtain the radome response temperature field under thermal load; performs static calculation to obtain the radome structural deformation field under thermal and force loads; obtains the deformed radome mesh model based on the initial finite element mesh model and the structural deformation field; uses Yee mesh to divide the electromagnetic calculation domain of the deformed radome; combines the dielectric temperature drift characteristics of the material to map and obtain the electromagnetic parameters of each Yee mesh; combines the boundary conditions to calculate the electrical performance of the radome using the time domain finite difference method. This solves the problem of accurately transmitting the dielectric temperature drift and structural deformation information of the radome body material caused by thermal loads to the electrical simulation model of the radome, and realizes the high-precision time domain full-wave numerical calculation of the electrical performance of the radome under the coupling of the thermal, mechanical and electrical fields, which can effectively ensure the consistency of the electrical performance design of the radome of high-speed aircraft in the sky and the earth.

[0125] Furthermore, based on the same technical concept, the present invention provides a computer-readable storage medium, which stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute a time-domain full-wave calculation method for the electrical performance of the antenna cover under thermal-mechanical-electric field coupling.

[0126] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A time-domain full-wave calculation method for the electrical performance of a radome under thermal-mechanical-electrical coupling, characterized in that: The specific steps include: Create a finite element mesh model for radome thermal calculations; Carry out transient thermal calculation to obtain the temperature field of the radome response under thermal load; Conduct static calculations to obtain the deformation field of the radome structure under thermal and mechanical loads; Based on the initial finite element mesh model and the structural deformation field, the mesh model of the deformed radome is obtained; Use Yee meshing to divide the electromagnetic calculation domain of the deformed radome; Combined with the dielectric temperature drift characteristics of the material, the electromagnetic parameters of each Yee grid are mapped and obtained; The electrical performance of the radome is calculated using the finite-difference time-domain method.

2. The time-domain full-wave calculation method for the electrical performance of the radome under thermal-mechanical-electrical coupling according to claim 1 is characterized in that: The method of obtaining a deformed radome mesh model based on the initial finite element mesh model and the structural deformation field includes: The deformation variables of the unit nodes of the initial finite element mesh model of the radome are superimposed on the deformation variables to obtain the deformed finite element mesh model, and the structural dimensions of the radome under flight conditions are determined.

3. The time-domain full-wave calculation method for the electrical performance of the radome under thermal-mechanical-electrical coupling according to claim 2 is characterized in that: The method of using Yee mesh to divide the electromagnetic calculation domain of the deformed radome includes: According to the finite element mesh model of the deformed radome, the electromagnetic calculation domain is determined and divided using the Yee mesh; The size of the Yee cell is determined by the calculation frequency and the electromagnetic properties of the target object, and is generally no larger than 1 / 12 of the wavelength of the cover material medium.

4. The time-domain full-wave calculation method for the electrical performance of the radome under thermal-mechanical-electrical coupling according to claim 3 is characterized in that: The dielectric temperature drift characteristics of the material include: The electromagnetic properties of the cover material usually vary with temperature; The electromagnetic properties of the cover material are obtained through high-temperature performance testing of the material. The temperature variation functions of the electromagnetic properties of the material include: the temperature variation function of the dielectric constant ε(T) and the temperature variation function of the conductivity σ(T).

5. The time-domain full-wave calculation method for the electrical performance of the radome under thermal-mechanical-electrical coupling according to claim 4 is characterized in that: The mapping obtains the electromagnetic parameters of each Yee grid, including: Based on the temperature variation function of the electromagnetic properties of the material, the temperature variation electromagnetic parameters on each Yee cell are obtained by interpolating the temperature field of the finite element unit after deformation.

6. The time-domain full-wave calculation method for the electrical performance of the radome under thermal-mechanical-electrical coupling according to claim 5 is characterized in that: The method of calculating the electrical performance by using the finite difference time domain method comprises: Based on Yee grid discretization, the second-order central difference format of discrete electromagnetic field quantities is used to approximate the first-order partial differentials of continuous electromagnetic field quantities with respect to space and time. The update formulas of each electromagnetic field component are derived. Combined with the boundary conditions, the solution of the electromagnetic calculation domain is iteratively calculated.

7. The time-domain full-wave calculation method for the electrical performance of the radome under thermal-mechanical-electrical coupling according to claim 6 is characterized in that: The finite element mesh model includes: mesh division using tetrahedral units, the size of the tetrahedral units is determined by the accuracy requirements of thermodynamic simulation calculations, and the size is generally larger than the size required for electromagnetic simulation.

8. The time-domain full-wave calculation method for the electrical performance of the radome under thermal-mechanical-electrical coupling according to claim 7 is characterized in that: The conditions of the heat load are: cold wall heat flux, recovery enthalpy and pressure that vary with time; hot wall heat flux that varies with time; or temperature that varies with time.

9. The time-domain full-wave calculation method for the electrical performance of the radome under thermal-mechanical-electrical coupling according to claim 8 is characterized in that: The force load conditions are aerodynamic pressure and inertia load.

10. A time-domain full-wave calculation device for electrical performance of a radome under thermal-mechanical-electrical coupling, applied to the method described in any one of claims 1 to 9, characterized in that: include: Finite element mesh model creation module, temperature field determination module, structural deformation field determination module, deformed radome mesh model determination module, electromagnetic mesh division module, electromagnetic parameter acquisition module, radome electrical performance calculation module, including: The finite element mesh model creation module is used to create a finite element mesh model for thermal calculation of the radome; The temperature field determination module is used to carry out transient thermal calculations to obtain the radome response temperature field under the action of thermal loads; The structural deformation field determination module is used to carry out static calculations to obtain the deformation field of the radome structure under the action of thermal and mechanical loads; The deformed radome mesh model determination module is used to obtain the deformed radome mesh model based on the initial finite element mesh model and the structural deformation field; The electromagnetic meshing module is used to divide the electromagnetic calculation domain of the deformed radome using Yee meshing; The electromagnetic parameter acquisition module is used to map and obtain the electromagnetic parameters of each Yee grid in combination with the dielectric temperature drift characteristics of the material; The antenna cover electrical performance calculation module is used to calculate the antenna cover electrical performance by using the finite difference time domain method.

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