A temperature and humidity and electromagnetic multi-physical field simulation method and device

Abstract

The application discloses a temperature and humidity and electromagnetic multi-physical field simulation method, comprising the following steps: determining the electrical performance parameters of air and insulating medium under the condition of a set temperature and humidity; performing fluid and thermodynamic simulation on a simulation space to obtain the distribution of temperature and humidity in the simulation space; determining the distribution of electrical performance parameters in the simulation space according to the distribution of temperature and humidity in the simulation space; and obtaining the electric field distribution in the simulation space through electromagnetic field numerical calculation. The application also contains a device for realizing the method. The application solves the problem of complex calculation of the comprehensive action of various physical processes such as the change of physical parameters of medium substances with temperature, humidity and electric field.

Description

Technical Field

[0001] This application relates to the field of electromagnetic field technology, and in particular to a method and apparatus for simulating temperature, humidity and electromagnetic multiphysics fields. Background Technology

[0002] Low-frequency electric field generating devices typically employ parallel-plate electric field generators. The parallel plates have an open structure, making the generated electric field susceptible to temperature and humidity fluctuations. The influence of ambient temperature and humidity on the electric field manifests in two ways. First, the electrical properties of the air dielectric change with ambient temperature and humidity. For example, the dielectric constant of air is a function of ambient temperature and humidity. Depending on the season, the temperature and humidity in the laboratory will vary, causing the air dielectric constant to change as well. Since the space between the parallel plates is filled with air, the electric field strength will vary with the air dielectric constant. Second, in humid weather, the air contains a large amount of water vapor, and this moisture can affect the transmission of electromagnetic waves.

[0003] Appendix F of the standard "IEC 61786-1 Requirements for testing instruments for measuring electromagnetic fields of human exposure at frequencies of 1 Hz to 100 kHz" publishes a set of test results for low-frequency electric fields under different humidity conditions. With the probe placed in the central region of the electric field, the test results curves show that relative humidity has a significant impact on the electric field test results, especially when the humidity is greater than 60%, the field strength test results deviate by more than several kilovolts per meter. This is due to both the influence of humidity on the probe and its effect on the field itself. Some literature mentions that when conducting calibration or comparison experiments of power frequency electric field testing equipment, the accuracy of calibration can be improved by suspending the sensor or maintaining a relative humidity in the laboratory environment below 55%.

[0004] The characteristics of the electric field in a parallel plate under different temperatures and humidity involve multi-physics simulations of electromagnetics, temperature, humidity, etc. In the simulation, the physical parameters of each medium are affected by a combination of physical processes such as temperature, humidity, and electric field changes. Therefore, the simulation calculation must adopt the coupling and solution of multi-physics equations such as electromagnetics, thermodynamics, and physical parameter equations of the model material. To date, it remains a complex and difficult type of simulation calculation. Summary of the Invention

[0005] This application proposes a multiphysics simulation method and apparatus for temperature, humidity, and electromagnetic fields, which solves the problem of complex calculation of the combined effects of various physical processes such as temperature, humidity, and electric field changes on the physical parameters of various media.

[0006] This application proposes a method for simulating temperature, humidity, and electromagnetic multiphysics fields, including the following steps:

[0007] Determine the electrical performance parameters of air and insulating medium under specified temperature and humidity conditions;

[0008] Fluid and thermodynamic simulations were performed on the simulation space to obtain the distribution of temperature and humidity in the simulation space.

[0009] Based on the distribution of temperature and humidity in the simulation space, determine the distribution of electrical performance parameters in the simulation space;

[0010] The electric field distribution in the simulation space is obtained through electromagnetic field numerical calculation.

[0011] Furthermore, prior to the step of obtaining the electric field distribution in the simulation space through numerical calculation of the electromagnetic field, the following steps are also included:

[0012] For the liquid film formed by condensation on the surface of a dielectric material, a theoretical model is established to calculate the relationship between the liquid film thickness and the dielectric constant, or...

[0013] The liquid film formed by condensation on the surface of the dielectric material is replaced by the water vapor concentration on the wall. The temperature and humidity distribution on the liquid film is obtained by simulation using fluid dynamics and thermodynamics analysis software. The electrical performance parameters of the dielectric under different temperature and humidity distribution regions are assigned.

[0014] As described in the embodiments of this application, the simulation space includes a parallel plate capacitor and four nylon support pillars distributed within the parallel plate capacitor to form the four vertices of a square.

[0015] Furthermore, the simulation space includes a water film wrapped around the surface of the flat plate capacitor or the surface of the nylon support.

[0016] Furthermore, it also includes the following steps: setting different liquid film thicknesses on the surface of the nylon support medium to obtain the offset caused by the electric field.

[0017] Furthermore, the electric field distribution is calculated under different temperatures and humidity levels to obtain the offset of the electric field caused by the different temperatures and humidity levels.

[0018] Furthermore, the dielectric constant of the nylon support medium is measured after immersing it in water at a set temperature.

[0019] This application also proposes a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the method described in any embodiment of this application.

[0020] This application also proposes an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method described in any embodiment of this application.

[0021] The above-described technical solutions adopted in the embodiments of this application can achieve the following beneficial effects:

[0022] Temperature and humidity affect the electric field through the medium acting on it (air, insulating support medium, etc.). Currently, there is no simulation software on the market that can directly couple the humidity field and the electric field. This application provides a simulation method for handling the relationship between temperature and humidity fields and the electric field. First, the influence of temperature and humidity on the electrical properties (conductivity, dielectric constant, etc.) of the medium (air, water vapor, non-metallic materials, etc.) between parallel plates is studied. Then, low-frequency electric field simulation software is used, assuming uniform or gradient distribution of temperature and humidity, to simulate the influence of changes in the electrical properties of the medium on the electric field, thereby identifying the influence of temperature and humidity on the electric field. At the same time, moisture easily condenses on the surface of the insulating support medium of the plates, which will seriously affect its insulation capacity. In most cases, the simulation of the influence of temperature and humidity on the electric field does not consider the condensation formed on the surface of the medium. This invention proposes to use a liquid film treatment method to simulate the influence of condensation on the electric field, which can accurately and comprehensively realize the coupled simulation of low-frequency electric field with temperature and humidity fields. Attached Figure Description

[0023] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0024] Figure 1 This is a flowchart illustrating an embodiment of the method of this application;

[0025] Figure 2 This is a schematic diagram of the central electric field observation area used in the simulation of a parallel-plate capacitor using the method of this application.

[0026] Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] This invention designs a method, specifically a multiphysics simulation method that couples a low-frequency electric field with a temperature field and a humidity field.

[0029] Temperature and humidity affect the electric field through the medium acting on it (air, insulating support medium, etc.). Currently, there is no simulation software on the market that can realize the direct coupling algorithm between the humidity field and the electric field.

[0030] A simulation method is invented to determine the simulation route and achieve coupled simulation of low-frequency electric fields with temperature and humidity fields. The simulation method first studies the effects of temperature and humidity on the electrical properties (conductivity, dielectric constant, etc.) of the medium (air, water vapor, non-metals, etc.) between parallel plates. Then, using low-frequency electric field simulation software, assuming uniform or gradient distribution of temperature and humidity, the influence of changes in the electrical properties of the medium on the electric field is simulated, thereby identifying the impact of temperature and humidity on the electric field. On the surface of the insulating support medium of the plates, moisture easily condenses, and the occurrence of condensation will seriously affect its insulation capacity. A liquid film treatment method is used to simulate the effect of condensation on the electric field. Using the above simulation method, coupled simulation analysis of temperature and humidity fields on the electric field can be achieved.

[0031] The technical solutions provided by the various embodiments of this application are described in detail below with reference to the accompanying drawings.

[0032] Figure 1 This is a flowchart illustrating an embodiment of the method of this application;

[0033] This application proposes a method for simulating temperature, humidity, and electromagnetic multiphysics fields, including the following steps:

[0034] Step 110: Determine the electrical performance parameters of air and insulating medium under the set temperature and humidity conditions.

[0035] First, the effects of temperature and humidity on the electrical properties (conductivity, dielectric constant, etc.) of the medium (air, water vapor, non-metals, etc.) between parallel plates are studied. For example, determining the electrical performance parameters of air and the insulating medium under set temperature and humidity conditions includes:

[0036] The dielectric constant of air is related to atmospheric pressure, temperature, and humidity as follows:

[0037]

[0038] P air That is, atmospheric pressure, φ is relative humidity, k is Boltzmann constant, T is absolute temperature, and P is atmospheric pressure. sat-vapour ε is the partial pressure of saturated water vapor; ε is the relative permittivity of air.

[0039] Furthermore, the dielectric constant of the nylon support medium is measured after immersing it in water at a set temperature.

[0040] Step 120: Perform fluid and thermodynamic simulations on the simulation space to obtain the distribution of temperature and humidity in the simulation space.

[0041] As described in the embodiments of this application, when calculating a low-frequency parallel plate electric field generator, the simulation space includes a parallel plate capacitor placed in an open space, and also includes four nylon support pillars distributed within the parallel plate capacitor to form the four vertices of a square.

[0042] Furthermore, the simulation space includes a water film wrapped around the surface of the flat plate capacitor or the surface of the nylon support.

[0043] Step 130: Determine the distribution of electrical performance parameters in the simulation space based on the distribution of temperature and humidity in the simulation space.

[0044] When assuming ideal conditions where humidity and temperature are uniformly distributed between parallel plates and the temperature and humidity within the region are constant, the process is relatively simple. The electrical performance parameters of air and the insulating medium at that temperature and humidity are directly found, and then simulated directly in the electric field simulation software via step 150.

[0045] When there is a stepped distribution of humidity and temperature between parallel plates, advanced fluid dynamics and thermodynamics simulations are required to obtain the temperature and humidity distribution in the plate region. Then, the dielectric electrical properties under different regions (different temperatures and humidity) are attached, and electric field simulation is performed through step 150.

[0046] In step 130, specifically, a thermal-humidity coupling analysis of the environment or dielectric is performed to obtain the humidity distribution; and, based on existing humidity and relative permittivity data, a functional relationship between the relative permittivity of the dielectric and humidity is established.

[0047] Step 140: Set the dielectric properties of the liquid film on the material surface in the simulation space.

[0048] On the surface of the insulating support medium between the plates, moisture easily condenses, and the condensation is treated using a liquid film method.

[0049] Option 1: For the liquid film formed by condensation on the surface of the dielectric material, the calculation can be based on the material handbook or existing experimental data. For example, if the air humidity is 80% for 4 hours, a liquid film with a thickness of 0.02 mm will be formed on the surface of the nylon dielectric. A theoretical model of the relationship between the liquid film thickness and the dielectric constant can be established for calculation.

[0050] Option 2: The liquid film formed by condensation on the surface of the medium is replaced by the water vapor concentration at the wall surface. This involves using fluid dynamics and thermodynamics analysis software to set the water vapor concentration in the air surrounding the medium, as well as the air velocity, temperature, and humidity at air interfaces such as air conditioning vents, doors, and windows. Through simulation based on fluid dynamics and thermodynamics principles, the distribution range and thickness of the liquid film formed on the medium surface, as well as the temperature and humidity distribution areas on the liquid film, are obtained. Electrical performance parameters of the medium under these conditions are then assigned to different temperature and humidity distribution areas.

[0051] Step 150: Obtain the electric field distribution in the simulation space through electromagnetic field numerical calculation.

[0052] By simulating the effect of changes in the electrical properties of the medium on the electric field, the influence of temperature and humidity on the electric field can be identified.

[0053] Furthermore, the electric field distribution is calculated under different temperatures and humidity levels to obtain the offset of the electric field caused by the different temperatures and humidity levels.

[0054] Furthermore, it also includes the following steps: setting different liquid film thicknesses on the surface of the nylon support medium to obtain the offset caused by the electric field.

[0055] The relationship between the electric field distribution and temperature and humidity in the parallel plate is solved based on the basic formulas of electromagnetic field (2) and temperature field (3):

[0056]

[0057]

[0058] in,

[0059]

[0060] In the formula: k0 is the free space wavenumber, ε r μ, σ, ρ, K, C p The relative permittivity, magnetic permeability, electrical conductivity, mass density, thermal conductivity, and heat capacity of the air between the parallel plates at varying temperatures and humidity are ε. n denoted as the imaginary part of the dielectric constant; E is the electric field strength. It should be noted that this application only lists the relationship between the dielectric constant and temperature and humidity (Equations 1-4); other parameters and their relationships with temperature and humidity are not expressed using formulas and can be assigned values ​​based on material handbooks or experimental data.

[0061] Using the above simulation method, a three-dimensional model of the parallel plate electric field generator is established to simulate the actual measurement environment. The electric field distribution around the insulating support medium and the electric field distribution between the plates are solved under different temperature and humidity conditions. This allows us to obtain the influence of temperature and humidity on the low-frequency electric field and realize the simulation of multiple physical fields between temperature, humidity and low-frequency electric field.

[0062] Figure 2 This is a schematic diagram of the central electric field observation area used in the simulation of a parallel-plate capacitor using the method of this application.

[0063] The method described in this application is used to simulate an open-structure parallel plate electric field generator. Based on the simulation route described above, a low-frequency electric field generator model is established. Within the computational space, this model includes parallel plates 21 and nylon support media 22, i.e., nylon struts. The parallel plates 21 have a diameter of 1.5m and a spacing of 0.75m. Four nylon struts 22 with a diameter of 0.08m are distributed at the four vertices of a central 0.8m*0.8m square. The plates are set to metal, and the support medium between the plates is nylon. It is known that the dielectric constant of nylon does not change significantly with temperature from 20℃ to 60℃, while the loss tangent changes from 0.02 to 0.06. Its water absorption rate has a significant impact on the dielectric constant. After immersion in water for 24 days at 23℃, the dielectric constant changes from 3.75 to 16. The electrical performance parameters of nylon under different temperatures and humidity conditions are then substituted into the model.

[0064] Following the simulation approach, simulations were conducted by setting different liquid film thicknesses on the surface of the supporting medium. This yielded the electric field distribution under different temperatures and humidity levels, allowing for a comparison of the offset caused by these different temperatures and humidity levels on the electric field.

[0065] For example, by setting different liquid film thicknesses on the surface of the supporting medium, assuming that the temperature and humidity are uniformly or gradiently distributed, the temperature and humidity parameters and distributions can be substituted into the low-frequency electric field simulation software to obtain the electric field distribution under different temperatures and humidity. The offset caused by different temperatures and humidity on the electric field can be compared, thereby realizing a simulation method that couples the calculation of low-frequency electric field, temperature field and humidity field.

[0066] A 0.27m x 0.27m x 0.27m cube at the center of the area between the two plates was designated as observation area 23. The simulation results are as follows:

[0067] Table 1 Comparison of Simulation Results of Electric Field Between Parallel Plates under Different Temperature and Humidity Conditions

[0068]

[0069]

[0070] Table 2 Comparison of simulation results of electric field between parallel plates under different temperatures, humidity levels, and water film thicknesses.

[0071]

[0072] Through simulation examples, we can see the effects of temperature and humidity on low-frequency electric fields, including:

[0073] When the humidity is constant, the electric field at the eight vertices and the center of the 270mm*270mm*270mm cube remains unchanged.

[0074] Temperature and humidity affect the electrical properties of nylon, causing changes in the electric field around the four nylon supports. Since the four supports are approximately 400mm from the center, the electric field strength at the center point varies by approximately 0.04% under different temperatures and humidity levels. Within a 270mm x 270mm x 270mm cube at the center of the field distribution, the maximum variation in field strength at different temperature and humidity levels is approximately 0.3%.

[0075] Simulations revealed that the effect of the water film on the electric field is independent of temperature and humidity, and is only related to the thickness of the liquid film; the maximum effect of the liquid film on the electric field is about 0.17% when the thickness is within 0.5 mm.

[0076] As can be seen from the above introduction, this invention differs from existing methods in the following ways: This invention first analyzes the influence of temperature and humidity on the electrical properties (conductivity, dielectric constant, etc.) of the medium (air, water vapor, non-metals, etc.) between parallel plates, obtaining specific electrical performance parameters of the medium. These parameters are then substituted into low-frequency electric field simulation software, assuming both uniform and gradient temperature and humidity distributions. The influence of changes in the medium's electrical properties on the low-frequency electric field is then simulated, thus identifying the impact of temperature and humidity on the low-frequency electric field. Simultaneously, since moisture easily condenses on the surface of the insulating support medium between the plates, a liquid film method is proposed to treat the condensation. This achieves coupled simulation of the low-frequency electric field and the temperature and humidity field in the low-frequency electric field generator, revealing the influence of temperature and humidity on the low-frequency electric field.

[0077] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0078] Therefore, this application also proposes a computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the methods described in any embodiment of this application.

[0079] Furthermore, this application also proposes an electronic device (or computing device) including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method described in any embodiment of this application.

[0080] In a typical configuration, a computing device includes one or more processors (CPUs), input / output interfaces, a network interface, and memory. Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0081] Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. The electronic device 600 shown is merely an example and should not impose any limitation on the function and scope of use of the embodiments of this application. It includes: one or more processors 620; and a storage device 610 for storing one or more programs, which, when run by the one or more processors 620, enable the one or more processors 620 to implement the simulation calculation method in any step 110 to 160 of the embodiments of this application.

[0082] The electronic device 600 also includes an input device 630 and an output device 640; the processor 620, storage device 610, input device 630 and output device 640 in the electronic device can be connected by a bus or other means, as shown in the figure, which is connected by a bus 650.

[0083] Storage device 610, as a computer-readable storage medium, can be used to store software programs, computer-executable programs, and module units, such as the program instructions corresponding to the cloud bottom height determination method in the embodiments of this application. Storage device 610 may mainly include a program storage area and a data storage area. The program storage area may store the operating system and at least one application program required for a function; the data storage area may store data created based on terminal usage, etc. Furthermore, storage device 610 may include high-speed random access memory and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some instances, storage device 610 may further include memory remotely located relative to processor 620, and these remote memories can be connected via a network.

[0084] Input device 630 can be used to receive input digital, character, or voice information, and to generate key signal inputs related to user settings and function control of the electronic device. Output device 640 may include electronic devices such as a display screen and a speaker.

[0085] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0086] The above description is merely an embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this application should be included within the scope of the claims of this application.

Claims

1. A multiphysics simulation method for temperature, humidity, and electromagnetic fields, characterized in that, Includes the following steps: Determine the electrical performance parameters of air and insulating medium under specified temperature and humidity conditions; Fluid and thermodynamic simulations were performed on the simulation space to obtain the distribution of temperature and humidity in the simulation space. Based on the distribution of temperature and humidity in the simulation space, determine the distribution of electrical performance parameters in the simulation space; For the liquid film formed by condensation on the surface of the dielectric material, a theoretical model is established to calculate the relationship between the liquid film thickness and the dielectric constant. Alternatively, the liquid film formed by condensation on the surface of the dielectric material is replaced by the water vapor concentration on the wall, and the temperature and humidity distribution on the liquid film is simulated. The dielectric electrical performance parameters under different temperature and humidity distribution regions are then assigned. The electric field distribution in the simulation space is obtained through electromagnetic field numerical calculation.

2. The multiphysics simulation method for temperature, humidity, and electromagnetic fields as described in claim 1, characterized in that, By simulating the effect of changes in the electrical properties of the medium on the electric field, the influence of temperature and humidity on the electric field can be identified.

3. The multiphysics simulation method for temperature, humidity, and electromagnetic fields as described in claim 1, characterized in that, The determination of the electrical performance parameters of air and insulating medium under set temperature and humidity conditions includes: The functional relationship between the dielectric constant of air and atmospheric pressure, temperature, and humidity is taken as follows: P air Here, φ is atmospheric pressure, φ is relative humidity, k is Boltzmann's constant, and T is absolute temperature. P sat-vapour ε is the partial pressure of saturated water vapor; ε is the relative permittivity of air.

4. The multiphysics simulation method for temperature, humidity, and electromagnetic fields as described in claim 1, characterized in that, The simulation space includes: A parallel plate capacitor contains four nylon struts distributed within the capacitor to form the four vertices of a square.

5. The multiphysics simulation method for temperature, humidity, and electromagnetic fields as described in claim 4, characterized in that, The simulation space contains a water film wrapped around the surface of the flat plate capacitor or the surface of the nylon support.

6. The multiphysics simulation method for temperature, humidity, and electromagnetic fields as described in claim 5, characterized in that, Different liquid film thicknesses were set on the surface of the nylon support medium to obtain the offset caused by the electric field.

7. The multiphysics simulation method for temperature, humidity, and electromagnetic fields as described in claim 5, characterized in that, The electric field distribution is calculated under different temperatures and humidity levels to obtain the offset of the electric field caused by the different temperatures and humidity levels.

8. The multiphysics simulation method for temperature, humidity, and electromagnetic fields as described in claim 4, characterized in that, The dielectric constant of the nylon support medium was measured after immersing it in water at a set temperature.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method as described in any one of claims 1-8.

10. An electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method as described in any one of claims 1-8.

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