Simulation method of honeycomb electromagnetic composite material with high wave-absorbing property

Abstract

The invention provides a simulation method of a honeycomb electromagnetic composite material with high wave-absorbing performance, and belongs to the technical field of electromagnetic functional material simulation. The simulation method comprises three parts of modeling of a honeycomb structure composite material, equivalent processing of a honeycomb wall and calculation of the RCS of the honeycomb structure, CST Studio Studio electromagnetic field simulation software is adopted, CST Microwave Studio is used for modeling of the honeycomb structure, the reflectivity and the RCS under 6-18 GHz are simulated, and therefore the wave absorbing performance of the honeycomb structure is reflected. According to the method, simulation calculation is carried out after equivalent treatment of the honeycomb structure thin medium, the simulation result is accurate, operation is easy, and a calculation basis can be provided for research of the wave absorbing performance of an actual honeycomb structure composite material.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic functional material simulation, and particularly to a simulation method for a honeycomb electromagnetic composite material with high wave absorption performance. Background Art

[0002] Radar absorbing honeycomb materials are structures often encountered in military engineering, ranging from stealth aircraft to electromagnetic shielding structures in components. Therefore, studying the electromagnetic scattering characteristics of such absorbing structures has important engineering value. Taking a stealth fighter as an example, to reduce the overall Radar Cross Section (RCS), stealth treatment must be carried out on each of its components. The electromagnetic property changes brought about by these materials and structures need to be evaluated and calculated using electromagnetic tools. For example, coated stealth materials can be efficiently solved by combining the surface integral equation with MLMFA (Multilevel Fast Multipole Algorithm), or further combined with the discontinuous Galerkin domain decomposition technique for solution, and relatively accurate results can be obtained.

[0003] For such thin-walled models as honeycombs, some classical computational electromagnetics algorithms are difficult to apply. To simulate such thin-walled media, for the surface integral equation, very fine triangular mesh division is required for the side walls, which will lead to a sharp increase in the overall number of meshes, and due to the excessive difference in mesh sizes between the side walls and the front surface, an ill-conditioned matrix appears, and the iteration difficulty increases sharply. For the volume integral equation, tetrahedral meshes are used for discretization, and the side walls are too thin, resulting in a sharp increase in the number of unknowns, and it is difficult to calculate even a slightly larger model. Existing research methods can only obtain a relatively good equivalent approximation effect for a standard honeycomb flat plate in the direction perpendicular to the honeycomb aperture, and it is still impossible to effectively obtain the broadband, wide-angle, and high-precision electromagnetic scattering characteristics of the honeycomb absorbing structure. Summary of the Invention

[0004] In view of the above problems in the prior art, the present application proposes a simulation method for a honeycomb electromagnetic composite material with high wave absorption performance, which uses the volume integral equation plus the thin dielectric sheet equivalent model to solve the problems of too thin side walls of the honeycomb, too many mesh numbers, and too large memory occupation.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] It includes three parts: modeling of the honeycomb structure composite material, equivalent treatment of the honeycomb wall, and calculation of the RCS of the honeycomb structure. The honeycomb structure is modeled as a thin dielectric equivalent model, and the model is calculated through CST software, and the RCS data is calculated by simulating the honeycomb height and the thickness of the wave-absorbing material.

[0007] Preferably, the honeycomb unit plane is a regular hexagon, and the side wall is a dielectric surface without thickness.

[0008] Preferably, the equivalent electromagnetic parameter processing method of the honeycomb wall is equivalent to a thin dielectric, which is jointly determined by the characteristic electromagnetic parameters of the honeycomb wall and the absorbing materials on both sides.

[0009] Preferably, the total thickness of the real honeycomb wall is 0.05 mm to 0.5 mm, including an aramid paper honeycomb substrate and two layers of absorbing materials.

[0010] Preferably, in the CST setting, when calculating the honeycomb, the electromagnetic wave frequency is 5 GHz to 18 GHz, the azimuth angle is the pitch angle -180° to 180°, the azimuth angle -180° to 180°, and the far-field energy field.

[0011] Preferably, the size of the honeycomb model (length * width * height) is from 50 mm * 50 mm * 20 mm to 600 mm * 600 mm * 100 mm.

[0012] A simulation method for honeycomb structural materials with high wave absorption performance includes the following steps:

[0013] Step 1: Use CST Microwave Studio software to model the honeycomb. According to the honeycomb cell size, a honeycomb wall unit without thickness is established, with the bottom in the XOY plane and the honeycomb wall perpendicular to the bottom surface. The honeycomb side length, height are the same as the real honeycomb cell, and the honeycomb wall thickness is 0. The honeycomb side length is set as l, and the height is h. l = 1.0 mm, 1.75 mm, 2.75 mm, 3.75 mm, h = 20 mm to 100 mm.

[0014] Step 2: Adjust the honeycomb cell in Step 1 so that two of its sides are parallel to the X-axis, and then array P x and P y lengths in the X-axis and Y-axis directions respectively. P x = 50 mm to 600 mm, P y = 50 mm to 600 mm. Use Boolean to merge all honeycomb cells and name it solid1. And set a layer of surface without thickness at the bottom, with the same size as the honeycomb flat plate, and name it solid2. The combination of solid1 and solid2 gives the honeycomb equivalent appearance model.

[0015] Step 3: According to the thin dielectric equivalent model, the honeycomb wall is divided into three layers. The middle layer is the white honeycomb substrate, and the electromagnetic parameters include the white honeycomb substrate thickness w1, the absorbing material thickness w2 on both sides, the equivalent dielectric constant ε, and the loss tangent tanδ. Set the new material Materials 1 according to the above electromagnetic parameters.

[0016] Step 4: Assign Materials 1 material to solid1 and PEC material to solid2.

[0017] Step 5: Set the scanning angles. The pitch angle is θ, and the azimuth angle is Ψ. θ ranges from -180° to 180°, and Ψ ranges from -180° to 180°.

[0018] Step 6: Click to start the calculation, which is the simulation method for the honeycomb electromagnetic composite material with high wave absorption performance.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] 1. The present invention uses a thin dielectric equivalent model to process the honeycomb wall, solving problems such as excessive sidewall grids, poor matrix properties, and high memory occupancy under full-size modeling of the honeycomb.

[0021] 2. The present invention uses the common software CST for simulation, which has low requirements for modeling and a fast iteration speed. Description of the Drawings

[0022] In the following, the present invention will be described in more detail based on the embodiments and with reference to the drawings. Among them:

[0023] Figure 1 is the thin dielectric equivalent honeycomb model diagram in Embodiment 1 of the present invention;

[0024] Figure 2 is the RCS simulation result diagram in Embodiment 1 of the present invention. Detailed Embodiment

[0025] The present invention will be further described below with reference to the drawings.

[0026] Embodiment 1

[0027] As Figure 1 shown, a preparation method for a honeycomb electromagnetic wave composite material with an internal absorber structure includes the following steps:

[0028] Step 1: Use the CST Microwave Studio software to model the honeycomb. Establish a honeycomb wall unit without thickness according to the honeycomb cell size. The bottom is in the XOY plane, and the honeycomb wall is perpendicular to the bottom surface. Among them, the honeycomb side length, height are the same as the real honeycomb cell, and the honeycomb wall thickness is 0. The honeycomb side length is set to l, and the height is h. l = 2.75 mm, h = 60 mm.

[0029] Step 2: Adjust the honeycomb unit in Step 1 so that two of its sides are parallel to the X-axis, and then array P x and P y in the X-axis and Y-axis directions respectively by a length of P x = 200 mm, P y= 200 mm. Use Boolean to merge all the honeycomb cells and name it solid1. Then set a layer of surface with no thickness at the bottom, whose size is the same as that of the honeycomb flat plate, and name it solid2. The combination of solid1 and solid2 gives the honeycomb equivalent appearance model.

[0030] Step 3: According to the thin dielectric equivalent model, the honeycomb wall is divided into three layers of thickness. The middle is the white honeycomb base with a thickness of w1 and a dielectric constant of 2. The absorbing materials on both sides have a thickness of w2 and a dielectric constant of ε1. Calculate the equivalent dielectric constant ε and the loss tangent tanδ according to the equivalent model. Set the new material Materials 1 in CST according to the above electromagnetic parameters.

[0031] Step 4: Assign the material Materials 1 to solid1 and the material PEC to solid2.

[0032] Step 5: Set the scanning angles. The elevation angle is θ and the azimuth angle is Ψ. θ ranges from -0° to 20°, and Ψ is 0°.

[0033] Step 6: Click to start the operation, which is the simulation method for the honeycomb electromagnetic composite material with high wave absorption performance.

[0034] Example 2

[0035] A preparation method for a honeycomb electromagnetic wave composite material with an internal absorber structure, comprising the following steps:

[0036] Step 1: Use the CST Microwave Studio software to model the honeycomb. Establish honeycomb wall units with no thickness according to the honeycomb cell size. The bottom is in the XOY plane, and the honeycomb wall is perpendicular to the bottom surface. The side length and height of the honeycomb are the same as those of the real honeycomb cells, and the thickness of the honeycomb wall is 0. Set the side length of the honeycomb as l and the height as h. l = 1.75 mm, h = 20 mm.

[0037] Step 2: Adjust the honeycomb cells in Step 1 so that two of their sides are parallel to the X-axis, and then array them in the X-axis and Y-axis directions by lengths Px and Py respectively. Px = 300 mm, Py = 300 mm. Use Boolean to merge all the honeycomb cells and name it solid1. Then set a layer of surface with no thickness at the bottom, whose size is the same as that of the honeycomb flat plate, and name it solid2. The combination of solid1 and solid2 gives the honeycomb equivalent appearance model.

[0038] Step 3: According to the thin dielectric equivalent model, the honeycomb wall is divided into three layers of thickness. The middle is the white honeycomb base with a thickness of w1 and a dielectric constant of 2. The thickness of the absorbing materials on both sides is w2 and the dielectric constant is ε1. Calculate the equivalent dielectric constant ε and the loss tangent tanδ according to the equivalent model. Set up the new material Materials 1 in CST according to the above electromagnetic parameters.

[0039] Step 4: Assign Materials 1 to solid1 and PEC to solid2.

[0040] Step 5: Set the scanning angles, the elevation angle is θ, the azimuth angle is Ψ, θ ranges from 0° to 90°, and Ψ is 0°.

[0041] Step 6: Click to start the operation, which is the simulation method for the honeycomb electromagnetic composite material with high wave absorption performance.

[0042] Example 3

[0043] A preparation method for a honeycomb electromagnetic wave composite material with an internal absorber structure includes the following steps:

[0044] Step 1: Use CST Microwave Studio software to model the honeycomb. Establish a honeycomb wall unit without thickness according to the honeycomb cell size. The bottom is on the XOY plane and the honeycomb wall is perpendicular to the bottom surface. The honeycomb side length, height are the same as the real honeycomb cell, and the honeycomb wall thickness is 0. Set the honeycomb side length as l and the height as h. l = 2.75mm, h = 100mm.

[0045] Step 2: Adjust the honeycomb unit in Step 1 so that two of its sides are parallel to the X-axis, and then array Px and Py lengths in the X-axis and Y-axis directions respectively. Px = 50mm, Py = 50mm. Use Boolean to merge all honeycomb units and name it solid1. And set a layer of surface without thickness at the bottom, with the same size as the honeycomb flat plate, and name it solid2. The combination of solid1 and solid2 gives the honeycomb equivalent appearance model.

[0046] Step 3: According to the thin dielectric equivalent model, the honeycomb wall is divided into three layers of thickness. The middle is the white honeycomb base with a thickness of w1 and a dielectric constant of 2. The thickness of the absorbing materials on both sides is w2 and the dielectric constant is ε1. Calculate the equivalent dielectric constant ε and the loss tangent tanδ according to the equivalent model. Set up the new material Materials 1 in CST according to the above electromagnetic parameters.

[0047] Step 4: Assign Materials 1 to solid1 and PEC to solid2.

[0048] Step Five: Set the scanning angles. The pitch angle is θ and the azimuth angle is Ψ. The pitch angle θ ranges from 0° to 90°, and the azimuth angle Ψ is 0°.

[0049] Step Six: Click "Start Calculation", which is the simulation method for the honeycomb electromagnetic composite material with high microwave absorption performance.

[0050] The above description is only for understanding the method and core idea of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the rights of the present invention.

Claims

1. A simulation method for a honeycomb electromagnetic composite material with high wave absorption performance, characterized in that, It includes the following steps: Step 1: Model the honeycomb. Establish a honeycomb wall unit without thickness according to the honeycomb cell size. The bottom is in the XOY plane, and the honeycomb wall is perpendicular to the bottom surface. Step 2: Adjust the honeycomb cells in Step 1 so that two of their sides are parallel to the X-axis, and then array P in the X-axis and Y-axis directions respectively x and P y Length, P x = 50 mm to 600 mm, P y = 50 mm to 600 mm, combine all the honeycomb cells; name it solid1; and set a layer of surface with no thickness at the bottom, the size of which is the same as that of the honeycomb flat plate, and name it solid2; the combination of solid1 and solid2 gives the honeycomb equivalent appearance model; Step 3: According to the thin dielectric equivalent model, the honeycomb wall is divided into three layers. The middle layer is the white honeycomb base, and the electromagnetic parameters include the thickness w1 of the white honeycomb base, the thickness w2 of the absorbing materials on both sides, the equivalent dielectric constant ε, and the loss tangent tanδ. Set the new material Materials 1 according to the above electromagnetic parameters. Step 4: Assign the material Materials 1 to solid1 and the PEC material to solid2. Step 5: Set the scanning angles. The elevation angle is θ, and the azimuth angle is Ψ. θ ranges from -180° to 180°, and Ψ ranges from -180° to 180°.

2. The simulation method of the honeycomb electromagnetic composite material with high wave absorption performance according to claim 1, characterized in that, The honeycomb cell plane is a regular hexagon, and the side wall is a dielectric surface without thickness.

3. The simulation method of the honeycomb electromagnetic composite material with high wave absorption performance according to claim 1, characterized in that, The thin dielectric equivalence of the honeycomb wall is jointly determined by the characteristic electromagnetic parameters including the honeycomb wall and the absorbing materials on both sides.

4. The simulation method of the honeycomb electromagnetic composite material with high wave absorption performance according to claim 1, characterized in that, The total thickness of the actual honeycomb wall is 0.05 mm to 0.5 mm, including an aramid paper honeycomb base and two layers of absorbing materials.

5. The simulation method of the honeycomb electromagnetic composite material with high wave absorption performance according to claim 1, characterized in that When calculating the honeycomb, the electromagnetic wave frequency is 5 GHz to 18 GHz.

6. The simulation method of the honeycomb electromagnetic composite material with high wave absorption performance according to claim 1, characterized in that The size of the honeycomb model: 50 mm ≤ length ≤ 600 mm, 50 mm ≤ width ≤ 600 mm, 20 mm ≤ height ≤ 100 mm.

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