A heat transfer process simulation method combining atomic evolution information and electronic equipment

Abstract

The application discloses a heat transfer process simulation method combining atomic evolution information and electronic equipment. The application aims at the defect that a two-temperature model (TTM) in molecular dynamics (MD) cannot identify a vacuum region when describing a non-continuous medium system, combines a finite element simulation method (FEM), identifies a density information file to identify a gap of the non-continuous medium system, and modifies coefficients in a heat transfer equation in real time. The application gets rid of the limitation that MD-TTM is only applicable to describing an electronic-lattice heat transfer process of a continuous medium system, and can describe atomic evolution information in a heat transfer process, thereby providing a theoretical basis for studying the heat transfer process of the non-continuous medium system at a micro scale.

Description

Technical Field

[0001] This invention belongs to the field of molecular dynamics simulation, specifically relating to a simulation method and electronic device for electron-lattice heat transfer processes in discontinuous media systems that incorporate atomic evolution information. Background Technology

[0002] In 1974, Anisimov et al. first proposed the two-temperature model (TTM) to describe electron-lattice nonequilibrium heat transfer. Since then, this model has been used in some studies to describe thermal effects in nanostructures, such as the effects of ablation and lasers on material properties. Molecular dynamics (MD) simulations are a very effective method for studying microscale problems. They simulate the interactions and motions of microscopic particles in a system composed of atomic nuclei and electrons using computers. MD methods primarily focus on the positions and velocities of atoms and do not explicitly consider the degrees of freedom of electrons. Therefore, MD methods can only accurately simulate and describe the interactions and heat conduction behavior between atoms, but cannot directly describe the heat transfer process of electrons. Finite element method (FEM) simulations also employ two-temperature models to simulate femtosecond laser ablation phenomena; however, due to the characteristics of FEM technology, it cannot describe atomic-level evolutionary information.

[0003] In 2003, Leonid V. Zhigilei et al. proposed a method combining TTM and MD. TTM describes laser energy absorption in electronic systems, energy exchange between electrons and phonons, and rapid electronic heat conduction in metals. MD is used to simulate non-equilibrium processes such as lattice overheating, melting, and ablation, enabling the description of laser action on materials at the microscale. However, this method is only suitable for describing heat transfer processes in continuous media systems. It cannot effectively identify and describe vacuum regions in discontinuous systems, nor can it describe the changes in electronic heat transfer processes caused by the evolution of numerous particle structures in real time, resulting in distortion problems.

[0004] In 2020, Sachin Kurian et al. used the MD method to establish a finite element thermal model containing a moving heat source to study the local melting and solidification process of randomly distributed aluminum nanopowder beds. However, the method used to deal with the voids between the powder beds was to achieve a close packing of the powder beds by using smaller powder sizes. Therefore, when applying this model to describe the selective melting process of powder beds with larger final sizes, it cannot accurately describe the heat transfer in the voids between the powders, which has certain limitations.

[0005] In 2022, Hao Huang et al. proposed a method based on TTM-MD to simulate the laser-induced fragmentation of nanoparticles in a liquid environment. This method described the size of clusters and the distribution of bubbles at each time step, and considered the influence of cluster size on the electron-phonon coupling process. However, this method focuses on simulating liquid boundary conditions and the influence of the distribution and size of the nanoparticles formed after cluster fragmentation on the electron-phonon coupling parameters at each time step. It cannot reflect the electron-lattice heat transfer process of discontinuous media at the atomic scale. Summary of the Invention

[0006] The purpose of this invention is to provide a simulation method and electronic device capable of describing the electron-lattice heat transfer process of discrete systems by incorporating atomic evolution information. This method focuses on reflecting the electron-lattice heat transfer process of discrete systems under ultrashort pulse laser irradiation at the atomic scale. It accurately identifies the vacuum region in the discontinuous system to obtain atomic structure evolution information of the heat transfer process, and then uses this structural evolution information to make real-time corrections to the heat transfer calculations, resulting in simulation heat transfer calculations that better reflect reality.

[0007] To achieve the above objectives, the present invention employs the following technical solution:

[0008] In a first aspect, the present invention provides a method for simulating heat transfer processes by incorporating atomic evolution information, comprising the following steps:

[0009] S1: Initialize the system settings, specifying the time step ΔT and total duration T for the heat transfer iteration calculation process;

[0010] S2: Input the atomic configuration file into the molecular dynamics calculation software to calculate the lattice temperature information file, atomic density information file, and atomic configuration file;

[0011] S3: Read the lattice temperature information file and atomic density information file output in step S2, and perform iterative calculation on the electron temperature: discretize the time term, discretize the second-order spatial partial derivative, integrate the calculation of the heat transfer equation into a matrix format to obtain the iterative formula, and then perform a single iteration calculation; output the electron temperature information file after the completion of this iteration calculation and update the lattice temperature information file.

[0012] S4: Read the atomic configuration file output in step S2, perform velocity scalar scaling, update the velocity information of each atom, and write a new atomic configuration file;

[0013] S5: Repeat steps S2 to S4 once for the new atomic configuration file to complete one iteration. A total of T / ΔT iterations are required.

[0014] Furthermore, step S1 includes: setting the mesh generation method for the discontinuous medium system, and setting the initial electron temperature field, external heat source field, time step ΔT and total duration T of the iterative calculation process.

[0015] Furthermore, in step S1, the initial electronic temperature field of the grid is 300K, i.e., room temperature.

[0016] Furthermore, step S2 includes the following sub-steps:

[0017] S2.1 In molecular dynamics calculation software (such as LAMMPS), read the atomic configuration file, including the coordinates and mass information of each atom;

[0018] S2.2 divides the system into multiple atomic blocks (e.g., grids or cubes), each block containing a certain number of atoms;

[0019] S2.3 For each atomic block, at specified step intervals, calculate the atomic number density information and store it in the density information file;

[0020] S2.4 For each atomic block, the velocity of the atoms within that block is statistically analyzed, and the average kinetic energy of the atoms within that block is calculated. Based on the theory of statistical physics, the kinetic energy is converted into temperature, and the temperature value is calculated using the average kinetic energy.

[0021] S2.5 Iterate through all atomic blocks, record the temperature of each atomic block and store it in the lattice temperature information file.

[0022] Furthermore, in step S2, the step size should be set at the femtosecond scale, so that atoms are unlikely to move a long distance in such a short time, the atomic evolution is not drastic, and the impact on the calculation of the subsequent heat transfer equation is small.

[0023] Furthermore, step S3 includes the following steps:

[0024] S3.1 The electron temperature is calculated using the two-dimensional electron heat transfer equation. The time term is discretized using the forward Euler method to obtain the electron heat transfer equation containing only the spatial term.

[0025] S3.2 further discretizes the second-order partial derivatives in space and uses the central difference method to extend the calculation of the single-grid node electron heat transfer equation to a matrix operation performed simultaneously on all grids; and further unifies the calculation of the heat transfer equations of all grids into matrix calculation.

[0026] S3.3 identifies voids in discontinuous media systems by recognizing atomic density information files and corrects the coefficients in the electron heat transfer equation;

[0027] S3.4 Calculate the global heat source in matrix form provided by the electron-lattice coupling process and assign it to the lattice temperature matrix;

[0028] S3.5 performs a single calculation on the modified electronic heat transfer equation, and outputs the lattice temperature matrix, electronic density matrix, electronic thermal conductivity matrix, electronic thermal capacity matrix, identification matrix, and thermal diffusivity matrix by combining the electronic-lattice coupling process.

[0029] S3.6 The calculated electron temperature matrix and lattice temperature matrix are processed to obtain the atoms and write them into the electron temperature information file and lattice temperature information file according to the input format of the atomic configuration file in the molecular dynamics calculation software.

[0030] Furthermore, in step S3, the two-dimensional electron heat transfer equation is:

[0031]

[0032] Where u represents the temperature field, which is a function of spatial coordinates (x, y) and time t, and a represents the thermal diffusivity. and q represents the heat diffusion terms in the x and y directions, respectively. v Let v0(x, y) represent the heat source term, and v0(x, y) represent the initial conditions.

[0033] After time and space discretization, a system of partial differential equations in matrix form with second-order partial derivatives is obtained:

[0034]

[0035] Here, A and B are called difference coefficient matrices, both of which are tridiagonal symmetric matrices, but of different sizes. A is (Nx, Nx) and B is (Ny, Ny).

[0036] U is the electron temperature matrix, which is represented as:

[0037]

[0038] Where Nx and Ny represent the number of grids in the x and y directions after initialization, respectively, and Δx and Δy represent the length of the grid in the x and y directions, respectively;

[0039] The iterative formula is:

[0040]

[0041] Among them, U n V0(X, Y) represents the temperature matrix at the nth step after time discretization, V0(X, Y) is the initial condition matrix obtained after spatial discretization, and Δt is the time step size of time discretization.

[0042] Furthermore, in step S3, the boundary points of the second-order partial derivative matrix obtained from the partial differential equation system in matrix form are invalid. The boundary conditions are set as follows:

[0043] (1) Isothermal boundary: Applicable to various simulation systems, especially large simulation systems, setting the matrix edge to a constant temperature, such as room temperature 300K;

[0044] (2) Constant heat flux boundary: Given the convective heat transfer coefficient h and the thermal conductivity λ of the medium at the boundary of the simulation system, the coefficient ch = λ / h is defined to reflect the relative magnitude of heat transfer by conduction and convection. Then, based on the ambient temperature U... env and internal node temperature U i，1 The weighted average is calculated using the following formula:

[0045]

[0046] Calculate the boundary temperature value U i，0 The other three boundaries are set in the same way;

[0047] (3) Periodic boundary: The electron temperature matrix U of the nth heat transfer iteration is copied and spliced ​​along the boundary directions of the simulation system, except for the isothermal and isothermal heat flux boundaries. n Simultaneously, using the same copying and splicing method, the lattice temperature matrix, electron density matrix, electronic thermal conductivity matrix, electronic thermal capacity matrix, identifier matrix, and thermal diffusivity matrix from the heat transfer calculation iterations are enlarged. The second-order partial derivative coefficient matrix is ​​expanded into a tridiagonal symmetric matrix with three times the number of rows or columns. Heat transfer calculations are then performed on the transformed large matrix, and the U value in the middle before splicing is truncated from the large temperature matrix obtained from the calculation results. n The corresponding region is used as the temperature result U obtained after this heat transfer iteration calculation. n+1 .

[0048] Furthermore, in step S3, the method for real-time correction of the coefficients in the heat transfer equation is as follows: by reading the density information file output by the molecular dynamics calculation software and mapping the density information onto the grid, for a certain grid i, a cross-shaped mask is used to cover i and the four surrounding grids for determination:

[0049] (1) If the density in i is zero and the density of the four surrounding grids is zero, then grid i is determined to be a vacuum grid and its electronic thermal conductivity is set to zero.

[0050] (2) If the density in i is zero and there are non-zero density grids in the four surrounding grids, then grid i is determined to be an edge grid. The temperature of the edge grid is specified to be the same as the temperature of the adjacent grid with atoms, and its internal heat transfer coefficient is set to infinite as an adiabatic boundary.

[0051] (3) If the density of grid i is less than 60% of the density of the block, then grid i is determined to be a low-density grid, and the thermal diffusivity of this grid is reduced to 1% of that of the block.

[0052] In the flag matrix, meshes without atoms are marked as False (flag value 0), and meshes containing atoms are marked as True (flag value 1).

[0053] Furthermore, in step S3, the electron-lattice coupling process uses the following formula:

[0054] Q el =G(T) e -T l )*flag

[0055] Among them, Q el T represents the amount of energy exchanged between electrons and the crystal lattice, where G represents the electron-lattice coupling strength. e T represents electron temperature. l This represents the lattice temperature, and flag is the flag value in the flag matrix.

[0056] Furthermore, step S4 specifically includes: reading the initial velocity value of each atom from the atomic configuration file provided in S2. Based on the relationship between atomic velocity and temperature:

[0057]

[0058] Calculate the initial temperature T corresponding to the atoms in the atomic configuration file provided in step S2. ori Where KE is the overall kinetic energy of N atoms, dim is the corresponding system dimension, and k R It is the Boltzmann constant, and T is the temperature corresponding to KE at this time;

[0059] From the lattice temperature matrix obtained in step S3, the matrix coordinate information is mapped with the atomic coordinate information in the atomic configuration file provided in step S2 to obtain the temperature T corresponding to each atom after calculation in step S3. new , will T new / T ori As a scaling factor, based on the relation T new / T oriPerform velocity scalar scaling to calculate the updated atomic velocities. It reads the required format from the molecular dynamics calculation software to create and output new atomic configuration files.

[0060] In a second aspect, the present invention provides a computer medium including a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor, when executing the program, implements the heat transfer process simulation method incorporating atomic evolution information as described in the first aspect.

[0061] Compared with the prior art, the present invention has the following beneficial effects:

[0062] (1) The simulation method described in this invention can overcome the problem of distortion caused by the inability to identify the vacuum region in the traditional dual-temperature model and the influence of the non-uniform and discontinuous medium system.

[0063] (2) The simulation method described in this invention can provide specific structural atomic-level evolution information and realize real-time simulation of the changes in electron heat transfer process brought about by the evolution of a large number of particle structures.

[0064] (3) The simulation method described in this invention provides a theoretical basis for studying the heat transfer process of discontinuous media systems at the microscale. Attached Figure Description

[0065] Figure 1 This is a flowchart of the steps in a heat transfer process simulation method incorporating atomic evolution information according to the present invention.

[0066] Figure 2 This is an initial model diagram according to an embodiment of the present invention.

[0067] Figure 3 This is a schematic diagram of a laser heating area according to an embodiment of the present invention.

[0068] Figure 4 This is information on the evolution of electron temperature at different times according to an embodiment of the present invention.

[0069] Figure 5 This is information on the evolution of lattice temperature at different times according to an embodiment of the present invention.

[0070] Figure 6 This is information on the evolution of atomic structure at different times according to an embodiment of the present invention. Detailed Implementation

[0071] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, and the technical solutions in the embodiments of the present invention will be clearly and completely described. However, the present invention is not limited to the following embodiments.

[0072] Example 1

[0073] like Figure 1 As shown, the heat transfer process simulation method combining atomic evolution information provided in this application includes the following specific steps:

[0074] S1: Initialize the system settings, specifying the time step ΔT and total duration T for the heat transfer iteration calculation process;

[0075] S2: Input the atomic configuration file into the molecular dynamics calculation software to calculate the lattice temperature information file, atomic density information file, and atomic configuration file;

[0076] Includes the following sub-steps:

[0077] S2.1 In molecular dynamics calculation software, read the atomic configuration file, including the coordinates and mass information of each atom;

[0078] S2.2 divides the system into multiple atomic blocks, each containing a certain number of atoms;

[0079] S2.3 For each atomic block, at specified step intervals, calculate the atomic number density information and store it in the density information file;

[0080] S2.4 For each atomic block, the velocity of the atoms within that block is statistically analyzed, and the average kinetic energy of the atoms within that block is calculated. Based on the theory of statistical physics, the kinetic energy is converted into temperature, and the temperature value is calculated using the average kinetic energy.

[0081] S2.5 Iterate through all atomic blocks, record the temperature of each atomic block and store it in the lattice temperature information file.

[0082] S3: Read the lattice temperature information file and atomic density information file output in step S2, and perform iterative calculation on the electron temperature: discretize the time term, discretize the second-order spatial partial derivative, integrate the calculation of the heat transfer equation into a matrix format to obtain the iterative formula, and then perform a single iteration calculation; output the electron temperature information file after the completion of this iteration calculation and update the lattice temperature information file.

[0083] Includes the following sub-steps:

[0084] S3.1 The electron temperature is calculated using the two-dimensional electron heat transfer equation. The time term is discretized using the forward Euler method to obtain the electron heat transfer equation containing only the spatial term.

[0085] S3.2 further discretizes the second-order partial derivatives in space and uses the central difference method to extend the calculation of the single-grid node electron heat transfer equation to a matrix operation performed simultaneously on all grids; and further unifies the calculation of the heat transfer equations of all grids into matrix calculation.

[0086] S3.3 identifies voids in discontinuous media systems by recognizing atomic density information files and corrects the coefficients in the electron heat transfer equation;

[0087] S3.4 Calculate the global heat source in matrix form provided by the electron-lattice coupling process, consider the lattice heat capacity, calculate the temperature change generated by the global heat source, and assign it to the lattice temperature matrix;

[0088] S3.5 performs a single calculation on the modified electronic heat transfer equation, and, in conjunction with the electron-lattice coupling process, outputs the lattice temperature matrix, electron density matrix, electronic thermal conductivity matrix, electronic thermal capacity matrix, identification matrix, and thermal diffusivity matrix, which are then stored in the global variables of the calculation program.

[0089] S3.6 The calculated electron temperature matrix and lattice temperature matrix are processed to obtain the atoms and write them into the electron temperature information file and lattice temperature information file according to the input format of the atomic configuration file in the molecular dynamics calculation software.

[0090] Furthermore, in step S3, the two-dimensional electron heat transfer equation is:

[0091]

[0092] Where u represents the temperature field, which is a function of spatial coordinates (x, y) and time t, and a represents the thermal diffusivity. and q represents the heat diffusion terms in the x and y directions, respectively. v Let v0(x, y) represent the heat source term, and v0(x, y) represent the initial conditions.

[0093] After time and space discretization, a system of partial differential equations in matrix form with second-order partial derivatives is obtained:

[0094]

[0095] Here, A and B are called difference coefficient matrices, both of which are tridiagonal symmetric matrices, but of different sizes. A is (Nx, Nx) and B is (Ny, Ny).

[0096] U is the electron temperature matrix, which is represented as:

[0097]

[0098] Where Nx and Ny represent the number of grids in the x and y directions after initialization, respectively, and Δx and Δy represent the length of the grid in the x and y directions, respectively;

[0099] The iterative formula is:

[0100]

[0101] Among them, U n V0(X, Y) represents the temperature matrix at the nth step after time discretization, V0(X, Y) is the initial condition matrix obtained after spatial discretization, and Δt is the time step size of time discretization.

[0102] Furthermore, in step S3, the electron-lattice coupling process uses the following formula:

[0103] Q el =G(T) e -T l )*flag

[0104] Among them, Q el T represents the amount of energy exchanged between electrons and the crystal lattice, where G represents the electron-lattice coupling strength. e T represents electron temperature. l This represents the lattice temperature, and flag is the flag value in the flag matrix.

[0105] S4: Read the atomic configuration file output in step S2, perform velocity scalar scaling, update the velocity information of each atom, and write a new atomic configuration file;

[0106] S5: Repeat steps S2 to S4 once for the new atomic configuration file to complete one iteration. A total of T / ΔT iterations are required.

[0107] The technical solution of the present invention will be further described below with reference to specific embodiments, specifically through selective laser sintering of aluminum metal particles:

[0108] Step S1: First, set the mesh generation method for the system, as shown in Table 1:

[0109] The system settings used in Table 1

[0110]

[0111] Next, the initial gradient heat source within the grid is set, i.e., the system evolving to the electron temperature field under specific conditions. The initial temperature of all grids is set to 300K (i.e., room temperature). The time step ΔT of the heat transfer calculation process is set to 0.0001fs, and the total duration is 5000fs. Step S1 ends.

[0112] Step S2: Run the molecular dynamics calculation software (LAMMPS in this embodiment). Select "metal" as the unit system in the input file; set the boundary conditions to free boundaries in the x and y directions and periodic boundaries in the z direction; set the time step to 0.001 ps and the total running time to 5 ps. Calculate the interatomic interaction forces using the eam / alloy potential function, using the Al-2009.eam.alloy potential function file as the input potential function. The molecular dynamics calculation software outputs the calculation results, including: atomic configuration file, lattice temperature information file, and atomic density information file.

[0113] Step S3: Read the initial state of the system from the input atomic configuration file, such as... Figure 2 The diagram shows the initial state of the model. Following the mesh generation method of the molecular dynamics calculation software in step S2, atomic blocks are divided into a two-dimensional mesh, and the density of each atomic block is calculated. Subsequently, the calculation results are averaged over time and summarized, and output to a density information file (density-profile.txt). The unit of density is atoms / ... Meanwhile, using the information of each atomic block as defined above, the lattice temperature distribution is calculated every specified number of steps and output to the lattice temperature information file (lattice-temperature-profile.txt).

[0114] The relevant physical parameters used in the heat transfer iterative calculation are shown in Table 2:

[0115] Table 2 Physical parameters used in the calculation process

[0116]

[0117] Electronic thermal conductivity and electronic heat capacity are used to control the electronic heat transfer process in the electronic heat transfer equation, while lattice heat capacity and electron-lattice coupling coefficient are used to control the lattice temperature change process in the electron-lattice coupling process.

[0118] In this embodiment, the time step size is set to 0.0001fs during the heat transfer iteration calculation, and the spatial step size after mesh generation is... Periodic boundary conditions are chosen. In this embodiment, regions without atoms are considered vacuum, and the surface of the object cannot transfer heat through radiation or convection to the outside; the surface energy mainly originates from the interior of the system. Therefore, the surface is approximated as an isothermal boundary. Based on the aforementioned parameter settings and calculation equations, heat transfer calculations are performed.

[0119] In this embodiment, since the system is at the nanoscale, the laser absorption rate and energy gradient can be appropriately omitted. Therefore, in this embodiment, the applied laser source has an energy density of 10 mW / cm². 2 A constant-intensity light source whose coverage does not change over time. For example... Figure 3 The figure shows the range in which the laser source is applied in the system of this embodiment.

[0120] Step S4: Read the atomic configuration file output in Step S2 and the lattice temperature matrix output in Step S3, perform velocity scalar scaling, update the velocity information of each atom, and write a new atomic configuration file according to the format required by the molecular dynamics calculation software. Then input the atomic configuration file into the molecular dynamics calculation software and repeat the above steps to start the loop iteration. In this embodiment, a total of 5000 iterations are required.

[0121] Step S5: Return to step S2 for the next iteration. After T / ΔT iterations, end the iteration loop. Organize all output result files and analyze the final calculated data.

[0122] like Figure 4 The figure shows the evolution of electron temperature at different times. Initially, the temperature is higher in the region where the heat source is applied; as the sintering process proceeds, the electron temperature rises rapidly and becomes uniformly distributed within each metal particle; during this process, the distribution of the electron temperature grid also changes with the simulation architecture.

[0123] like Figure 5 The figure shows the evolution of lattice temperature at different times. As the sintering process proceeds, the lattice temperature gradually increases, but significantly slower than the rate of increase in electron temperature. Within each metal particle, the lattice temperature follows a Gaussian distribution, unlike the uniform distribution of electron temperature. During this process, the distribution of lattice temperature also changes with the simulation system architecture.

[0124] like Figure 6 The diagram shows the evolution of atomic structure at different times. As the sintering process progresses, the number of aluminum atoms whose structure changes gradually increases; by 3 ps of sintering, more than 95% of the aluminum atoms have undergone structural changes.

[0125] Example 2

[0126] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the heat transfer process simulation method incorporating atomic evolution information as described in Example 1.

[0127] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the invention.

Claims

1. A method for simulating heat transfer processes by incorporating atomic evolution information, characterized in that, Includes the following steps: S1: Initialize the system and specify the time step ΔT and total duration T for the heat transfer iteration calculation process; S2: Input the atomic configuration file into the molecular dynamics calculation software to calculate the lattice temperature information file, atomic density information file, and atomic configuration file; S3: Read the lattice temperature information file and atomic density information file output in step S2, and perform iterative calculation on the electron temperature: discretize the time term, discretize the second-order spatial partial derivative, integrate the calculation of the heat transfer equation into a matrix format to obtain the iterative formula, and then perform a single iteration calculation; output the electron temperature information file after the completion of this iteration calculation and update the lattice temperature information file. S3 includes the following sub-steps: S3.1 The electron temperature is calculated using the two-dimensional electron heat transfer equation. The time term is discretized using the forward Euler method to obtain the electron heat transfer equation containing only the spatial term. S3.2 further discretizes the second-order partial derivatives in space and uses the central difference method to extend the calculation of the single-grid node electron heat transfer equation to a matrix operation performed simultaneously on all grids; and further unifies the calculation of the heat transfer equations of all grids into matrix calculation. S3.3 identifies voids in discontinuous media systems by recognizing atomic density information files and corrects the coefficients in the electron heat transfer equation; S3.4 Calculate the global heat source in matrix form provided by the electron-lattice coupling process and assign it to the lattice temperature matrix; S3.5 performs a single calculation on the modified electronic heat transfer equation, and outputs the lattice temperature matrix, electronic density matrix, electronic thermal conductivity matrix, electronic thermal capacity matrix, identification matrix, and thermal diffusivity matrix by combining the electronic-lattice coupling process. S3.6 The calculated electron temperature matrix and lattice temperature matrix are processed to obtain the atoms and write them into the electron temperature information file and lattice temperature information file according to the input format of the atomic configuration file in the molecular dynamics calculation software. S4: Read the atomic configuration file output in step S2, perform velocity scalar scaling, update the velocity information of each atom, and write a new atomic configuration file; S5: Repeat steps S2~S4 once for the new atomic configuration file to complete one iteration. A total of T / ΔT iterations are required to obtain the final atomic configuration file.

2. The heat transfer process simulation method incorporating atomic evolution information according to claim 1, characterized in that, Step S1 includes: setting the mesh generation method for the discontinuous medium system, and setting the initial electron temperature field, external heat source field, time step ΔT and total duration T of the iterative calculation process.

3. The heat transfer process simulation method incorporating atomic evolution information according to claim 1, characterized in that, Step S2 includes the following sub-steps: S2.1 In molecular dynamics calculation software, read the atomic configuration file, including the coordinates and mass information of each atom; S2.2 divides the system into multiple atomic blocks, each containing a certain number of atoms; S2.3 For each atomic block, at specified step intervals, calculate the atomic number density information and store it in the density information file; S2.4 For each atomic block, the velocity of the atoms within that block is statistically analyzed, and the average kinetic energy of the atoms within that block is calculated. Based on the theory of statistical physics, the kinetic energy is converted into temperature, and the temperature value is calculated using the average kinetic energy. S2.5 Iterate through all atomic blocks, record the temperature of each atomic block and store it in the lattice temperature information file.

4. The heat transfer process simulation method incorporating atomic evolution information according to claim 1, characterized in that, In step S3, the two-dimensional electron heat transfer equation is: Where u represents the temperature field, which is a function of spatial coordinates (x, y) and time t. Represents the thermal diffusivity. and These represent the heat diffusion terms in the x and y directions, respectively. Represents the heat source term. Represents the initial condition; After time and space discretization, a system of partial differential equations in matrix form with second-order partial derivatives is obtained: Here, A and B are called difference coefficient matrices, both of which are tridiagonal symmetric matrices, but of different sizes. A is (Nx, Nx) and B is (Ny, Ny). U is the electron temperature matrix, which is represented as: Where Nx and Ny represent the number of grid cells in the x and y directions after initialization, respectively. and These represent the lengths of the grid in the x and y directions, respectively. The iterative formula is: in, This represents the temperature matrix at the nth step after time discretization. This is the initial condition matrix obtained after spatial discretization. The time step is the time step for time discrete-time operation.

5. The heat transfer process simulation method incorporating atomic evolution information according to claim 4, characterized in that, In step S3, the boundary points of the second-order partial derivative matrix obtained from the partial differential equation system in matrix form are invalid. Next, the boundary conditions are selected according to the simulation system's boundary condition setting method, as follows: (1) Isothermal boundary: Applicable to various simulation systems, setting the matrix edge to a constant temperature; (2) Constant heat flux boundary: Given the convective heat transfer coefficient h and the thermal conductivity λ of the medium at the boundary of the simulation system, define the coefficients. It reflects the relative magnitude of heat transfer due to heat conduction and convection, and thus depends on the ambient temperature. and internal node temperature The weighted average is calculated using the following formula: Calculate the boundary temperature value The other three boundaries are set in the same way; (3) Periodic boundary: The electron temperature matrix of the nth heat transfer iteration is copied and spliced ​​along the boundary directions of the simulation system, except for the isothermal and isothermal heat flux boundaries. Simultaneously, using the same copying and splicing method, the lattice temperature matrix, electron density matrix, electronic thermal conductivity matrix, electronic thermal capacity matrix, identifier matrix, and thermal diffusivity coefficient matrix from the heat transfer calculation iterations are enlarged. The second-order partial derivative coefficient matrix is ​​expanded into a tridiagonal symmetric matrix with three times the number of rows or columns. Heat transfer calculations are then performed on the transformed large matrix, and the large temperature matrix obtained from the calculations is truncated to the middle position before splicing. The corresponding region is used as the temperature result obtained after this heat transfer iteration calculation. .

6. The heat transfer process simulation method incorporating atomic evolution information according to claim 1, characterized in that, In step S3, the method for real-time correction of the coefficients in the heat transfer equation is as follows: by reading the density information file output by the molecular dynamics calculation software and mapping the density information to the grid, for a certain grid i, a cross-shaped mask is used to cover i and the four surrounding grids for judgment: (1) If the density in i is zero and the density of the four surrounding grids is zero, then grid i is determined to be a vacuum grid, and its electronic thermal conductivity is set to zero; (2) If the density in i is zero and there are grids with non-zero density in the four surrounding grids, then grid i is determined to be an edge grid, the temperature of the edge grid is specified to be consistent with the temperature of the adjacent grid with atoms, and its internal heat transfer coefficient is set to infinite as an adiabatic boundary; (3) If the density in i is less than 60% of the bulk density, then grid i is determined to be a low-density grid, and the thermal diffusivity in this grid is reduced to 1% of the bulk density.

7. The heat transfer process simulation method incorporating atomic evolution information according to claim 1, characterized in that, In step S3, the electron-lattice coupling process uses the following formula: in, G represents the energy exchange between electrons and the crystal lattice, and G represents the electron-lattice coupling strength. Indicates electron temperature, This represents the lattice temperature, and flag is the flag value in the flag matrix.

8. The heat transfer process simulation method incorporating atomic evolution information according to claim 1, characterized in that, Step S4 specifically includes: reading the initial velocity value of each atom from the atomic configuration file provided in S2. Based on the relationship between atomic velocity and temperature: Calculate the initial temperature corresponding to the atoms in the atomic configuration file provided in step S2. KE is The total kinetic energy of the atoms, where m is the mass of a single atom. v It refers to the velocity possessed by the atom, and dim is the corresponding system dimension. It is the Boltzmann constant. It is the temperature value corresponding to KE; From the lattice temperature matrix obtained in step S3, the matrix coordinate information is mapped to the atomic coordinate information in the atomic configuration file provided in step S2 to obtain the temperature corresponding to each atom after calculation in step S3. ,Will As a scaling factor, based on the relation Perform velocity scalar scaling to calculate the updated atomic velocities. The software reads the data into the required format according to the molecular dynamics calculation software to write new atomic configuration files and output them.

9. 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 program, it implements the heat transfer process simulation method incorporating atomic evolution information as described in any one of claims 1 to 8.

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