Method and program for radiation refrigeration type intelligent window structure based on finite element analysis multi-physics field numerical simulation

Abstract

The invention relates to a multi-physics field numerical simulation method based on finite element analysis, in particular to a simulation method and program for building a 3D vanadium dioxide and silicon dioxide core-shell coating structure model, and the model building simulation steps sequentially comprise parameter definition setting, model parameter setting, material setting, mesh refining and research and result setting. Establishing a 3D model; compiling a program of a self-generated model; and the like. The invention further relates to application of the method for simulating the multi-physical field numerical simulation based on finite element analysis to the adjustable transmittance and the adjustable radiation capacity of the core-shell structure in the fields of intelligent windows, infrared stealth, energy-saving glass and radiation refrigeration. The method solves the problems that it is difficult to establish a core-shell structure shell layer formed by randomly distributed vanadium dioxide nanoparticles in simulation software, and modeling and simulation of absorption, scattering and light absorption characteristics of the core-shell structure shell layer are carried out in a multi-physical field numerical simulation method of finite element analysis.

Description

Technical Field

[0001] The present invention relates to the field of microelectronic device preparation, and in particular to a method and program for a radiant cooling smart window structure based on multi-physical field numerical simulation of finite element analysis, as well as a self-programming method for forming a 3D model; specifically, a method and program for a radiant cooling smart window structure based on multi-physical field numerical simulation of finite element analysis, and a radiant cooling smart window simulation method and program are creatively proposed. Technical Background

[0002] Building energy consumption accounts for more than one-third of the total social energy consumption, of which about 65% is caused by windows. In order to reduce the total energy consumption of buildings, thermochromic smart window technology can be used to automatically adjust the solar energy transmittance and reduce window energy consumption. Radiative cooling technology can radiate the heat released by the building to the cold outer space to achieve thermal cooling. The combined use of these two technologies can achieve effective energy regulation and reduce building energy consumption. In addition, when the model is at the micro-nano size, the size effect and the interaction between particles are the key factors affecting the performance of the device. The experimental results are the results shown by the nanoparticles as a whole. It is impossible to accurately know the interaction between particles, and it is also impossible to give the direction of experimental optimization.

[0003] The multi-physics numerical simulation method based on finite element analysis stands out in engineering, science and research for its unique multi-physics simulation capabilities. Its advantages lie in the use of finite element method and iterative solution methods to solve the coupling of large-scale nonlinear problems with different physical phenomena, built-in material library, high openness and scalability. Vanadium dioxide (VO2) nanoparticles will undergo a metal-semiconductor phase transition at a phase transition temperature of about 68°C, accompanied by a sudden change in electrical, mechanical, magnetic and optical properties; silicon dioxide nanoparticles have good visible light transmittance and a large specific surface area. With the development of microelectronic devices towards miniaturization and reliability, the multi-physics numerical simulation method of finite element analysis used to simulate the performance of radiative cooling smart windows has become an important research tool in the field of improving the performance of microelectronic devices.

[0004] Traditional algorithms for simulating radiation cooling smart windows mainly include FDTD, FITD, MoM, BMF, etc. The requirements for 3D model size, simulation memory, and mesh during the simulation process hinder its large-scale promotion and use. The lack of theoretical calculations leads to the inability to obtain accurate theoretical support for some phenomena in the experiment. Therefore, providing better software for simulating radiation cooling smart window devices can provide better theoretical guidance and preliminary verification for scientific research. Summary of the invention 1. Technical issues to be resolved In view of the many deficiencies of dimming devices based on vanadium dioxide materials currently used in microelectronic fields such as smart windows and radiative cooling that cannot be explained experimentally, the present invention provides a method and program for radiative cooling smart window structure based on multi-physical field numerical simulation of finite element analysis, including the establishment of 3D models, program compilation, mesh refinement, setting of global variables and integral area, etc., and at the same time, the extinction, scattering and absorption characteristics of the simulated core-shell structure are used to explain the problems encountered in the experiment, further providing theoretical support for the experimental results and promoting the development of microelectronic devices. (II) Technical solution In order to achieve the above object, the present invention provides a method and program for a radiative cooling type smart window structure based on multi-physical field numerical simulation of finite element analysis, characterized in that it includes the following steps: Step 1: First, a 3D simulation model is established according to the size of silicon dioxide and vanadium dioxide nanoparticles in the experiment, and an air layer is established in a finite element simulation platform, and the established model is simulated in the air model; Step 2: Compile the randomly generated vanadium dioxide nanoparticle program. The program requires that the size of the vanadium dioxide nanoparticles is randomly distributed between 40-60nm, there are no overlapping vanadium dioxide nanoparticles, and the diameters of all vanadium dioxide nanoparticles are connected to form a hollow circle. The program is as follows; Step 3, establish R0, lda, t_air, t_pml, R1 and I0 parameters as the sphere radius, wavelength, air thickness around the sphere, PML layer thickness, vanadium dioxide nanoparticle layer thickness and incident light intensity respectively; Step 4, defining all vanadium dioxide nanoparticles as surface area integral, all nanoparticles and silicon dioxide nanoparticles as volume integral, and a perfectly matched layer respectively; Step 5, respectively setting the material refractive indexes of vanadium dioxide (inserted into M phase and R phase respectively), silicon dioxide and air; Step 6. In the electromagnetic wave options, add the far field as the receiving model for absorbed and scattered light; Step 7: Set up parameter sweep, use wavelength as variable, set up the grid, and start calculation. The advantages of the present invention are that the scattering, absorption and extinction characteristics of the core-shell structure formed by multiple particles before and after the vanadium dioxide phase transition are successfully established and simulated. A program for automatically generating a hollow circle of vanadium dioxide nanoparticles within a controllable size range is written using a self-written program. The model of the present invention can simulate the interaction and optical characteristics of most core-shell structures under electromagnetic wave irradiation. It promotes the development of radiation cooling type smart windows in simulation experimental results. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 A method and a program flow chart of a radiant cooling smart window structure based on multi-physical field numerical simulation of finite element analysis according to an embodiment of the present invention. Figure 2 This is a 3D model of the core-shell structure composed of vanadium dioxide nanoparticles and silicon dioxide nanoparticles in the present invention. Figure 3 The mesh of the 3D model in the present invention is established. Figure 4 Method calls written for the program in the present invention. Figure 5 This is the spectral curve for simulating extinction, scattering and absorption in the present invention.

Explanation of symbols

Claims

1. A method and program for a radiative cooling smart window structure based on multi-physics field numerical simulation of finite element analysis, characterized in that: Using the multi-physics field numerical simulation platform of finite element analysis, a model of nano-scale vanadium dioxide nanoparticles dispersed discretely on the micron-scale silicon dioxide surface was established, which was creatively applied to smart windows and radiation cooling technology. The specific operations are as follows: Step 1: First, a 3D simulation model is established according to the size of the silicon dioxide and vanadium dioxide nanoparticles in the experiment, and an air layer is established on a multi-physics field numerical simulation platform of finite element analysis, and the established model is simulated in the air model; Step 2: Write a program to randomly generate vanadium dioxide nanoparticles. The program requires that the size of vanadium dioxide nanoparticles is randomly distributed between 40-60nm, there are no overlapping vanadium dioxide nanoparticles, and the diameters of all vanadium dioxide nanoparticles are connected to form a hollow circle. The program is as follows; Step 3, establish R0, lda, t_air, t_pml, R1 and I0 parameters as the sphere radius, wavelength, air thickness around the sphere, PML layer thickness, vanadium dioxide nanoparticle layer thickness and incident light intensity respectively; Step 4, defining all vanadium dioxide nanoparticles as surface area integral, all nanoparticles and silicon dioxide nanoparticles as volume integral, and a perfect matching layer respectively; Step 5, respectively setting the material refractive indexes of vanadium dioxide (inserted into M phase and R phase respectively), silicon dioxide and air; Step 6. In the electromagnetic wave options, add the far field as the receiving model for absorbed and scattered light; Step 7: Set up parameter sweep, use wavelength as variable, set up the grid, and start calculation.

2. A method and program for a radiation cooling type intelligent window structure based on multi-physical field numerical simulation of finite element analysis according to claim 1, characterized in that: The multi-physics field numerical simulation method of finite element analysis is used to establish and simulate the nano core-shell structure model of the radiation cooling smart window.

3. A method and program for a radiation cooling type intelligent window structure based on multi-physics field numerical simulation of finite element analysis according to claim 1, characterized in that: The calling method is used to program and automatically generate randomly distributed vanadium dioxide nanoparticles, and the size range varies randomly within a controllable range, and all the vanadium dioxide nanoparticles form a hollow circle.

4. A method and program for a radiation cooling type intelligent window structure based on multi-physical field numerical simulation of finite element analysis according to claim 1, characterized in that: Detailed procedure for the random growth of vanadium dioxide nanoparticles.

5. A method and program for a radiation cooling type intelligent window structure based on multi-physical field numerical simulation of finite element analysis according to claim 1, characterized in that: The multi-physics field numerical simulation platform based on finite element analysis simulates the scattering, absorption and extinction characteristics of the core-shell structure of randomly distributed nanoparticles, with emissivity greater than or equal to 0.4, visible light transmittance greater than or equal to 0.5, and solar modulation efficiency greater than or equal to 0.

08.

6. A method and program for a radiation cooling type intelligent window structure based on multi-physical field numerical simulation of finite element analysis according to claims 1-5, characterized in that: The established model simulates and explains the theoretical calculations of the core-shell structure based on the experimental results.

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