Simulation method for heat and mass transfer process of tobacco section and related equipment

Abstract

The invention discloses an analogue simulation method for a heat and mass transfer process of a tobacco section and related equipment. According to the method, firstly, three-dimensional geometric models of the heating non-combustion smoking set and the heating non-combustion cigarette are established through three-dimensional modeling software, network division processing is carried out, and a quality grid is obtained; importing the quality grid into analogue simulation software, and setting a solver of the analogue simulation software according to a user-defined function UDF; and finally, operating analogue simulation software to carry out simulation calculation to obtain the release amount of the key tobacco components in the tobacco section in the heating process. In the process, a solver of the analogue simulation software is set by adopting a UDF program, so that the heat and mass transfer simulation of the tobacco section is realized on the basis of saving the experimental cost and improving the research efficiency, and an improved Arrhenius formula in the UDF is solved when the analogue simulation software is operated to carry out simulation calculation, so that the heat and mass transfer simulation of the tobacco section is realized. The release amount of key tobacco components of the tobacco section can be accurately simulated, so that the simulation precision is improved.

Description

Technical Field

[0001] The present application relates to the technical field of numerical simulation of heat transfer and mass transfer in tobacco segments, and particularly to a simulation method for the heat transfer and mass transfer process of tobacco segments and related equipment. Background Art

[0002] Compared with traditional cigarettes, new tobacco products use heating instead of combustion, significantly reducing the generation of harmful substances, and thus having lower health risks. In recent years, with the continuous development of heat-not-burn technology, new tobacco products have been widely promoted and applied in the market, especially showing significant advantages in meeting consumers' health needs.

[0003] However, with the continuous upgrading of new tobacco products, consumers' requirements for product quality have become increasingly strict. How to improve product performance, optimize the smoking experience, and effectively control the release of tobacco components has become an important issue in the research and development of heat-not-burn smoking devices. Existing research mainly focuses on the influence of the airflow field and temperature field on the release of key tobacco components in heat-not-burn cigarettes, and attempts to control the concentration and composition of key tobacco components by optimizing the heating process.

[0004] Current research on new tobacco products (the release characteristics of key tobacco components in heat-not-burn cigarettes) mostly relies on experimental measurements, collecting and analyzing the released key tobacco components, which is not only cumbersome and costly, but also difficult to meet the requirements of efficient and accurate research. Summary of the Invention

[0005] The present application provides a simulation method for the heat transfer and mass transfer process of tobacco segments and related equipment. By using the numerical simulation method and user-defined function UDF to conduct heat transfer and mass transfer simulation on heat-not-burn cigarettes, it can not only save experimental costs, but also improve research efficiency and obtain more accurate results through computer program operations.

[0006] In a first aspect, the present application provides a simulation method for the heat transfer and mass transfer process of tobacco segments, the method comprising:

[0007] Using three-dimensional modeling software to establish three-dimensional geometric models of heat-not-burn smoking devices and heat-not-burn cigarette sticks, and performing mesh division processing on the three-dimensional geometric models to obtain quality meshes;

[0008] Importing the quality meshes into simulation software, and setting the solver of the simulation software according to the user-defined function UDF. The UDF includes heat transfer and mass transfer functions of tobacco components in the tobacco segment, functions of suction conditions, functions simulating the filter tip interception effect, and thermal property functions of the tobacco segment during the heating process. The thermal decomposition release kinetic equation in the heat transfer and mass transfer function is an improved Arrhenius formula;

[0009] Run the simulation software to perform simulation calculations and obtain the release amounts of key tobacco components in the tobacco section during the heating process of the heat-not-burn smoking device and the heat-not-burn cigarette.

[0010] Optionally, perform mesh division processing on the three-dimensional geometric model to obtain a quality mesh, including:

[0011] Divide the mesh of the heating body region in the three-dimensional geometric model to obtain a heating body mesh;

[0012] Divide the mesh of the gap space between the heating body region and the tobacco section in the three-dimensional geometric model to obtain a gap space mesh;

[0013] Divide the mesh of the tobacco section in the three-dimensional geometric model to obtain a tobacco section mesh;

[0014] Process the heating body mesh, the gap space mesh, and the tobacco section mesh in the form of coupled nodes to obtain a quality mesh.

[0015] Optionally, the process of obtaining the user-defined function UDF includes:

[0016] Use the UDF program to set the heat and mass transfer function, and the heat and mass transfer function includes the pyrolysis release kinetics equation of the material in the tobacco section, the endothermic and exothermic function of water phase change, and the endothermic effect function of glycerol;

[0017] Use the UDF program to set the function of the suction condition and the function of simulating the filter tip interception effect;

[0018] Use the UDF program to set the thermophysical property function, and the thermophysical property function includes the function of the variation of the physical property parameters of the tobacco section with temperature during the heating process.

[0019] Optionally, set the solver of the simulation software according to the user-defined function UDF, including:

[0020] Select the unsteady state model in the solver;

[0021] Load the thermophysical property function, the heat and mass transfer function, the function of the suction condition, and the function of simulating the filter tip interception effect into the simulation software through the UDF program;

[0022] Couple the thermophysical property function with the temperature field of the simulation software;

[0023] Set the heat and mass transfer function as the property parameters of the material in the tobacco section, and the property parameters include the pyrolysis temperature and volatilization kinetics parameters of the material in the tobacco section, the phase change characteristics of water, and the endothermic effect of glycerol;

[0024] Set the initial conditions and boundary conditions in the simulation software. The initial conditions include the initial temperature of the tobacco section and the heat transfer boundary conditions between the surface of the heating element and the tobacco section. The boundary conditions include the inlet velocity of the airflow field and the outlet pressure.

[0025] Optionally, the improved Arrhenius formula includes:

[0026]

[0027] where k i is the volatilization rate of the i-th substance; A is the frequency factor, indicating the number of possible reactions per unit time and per unit volume if the reactant molecules have enough energy to overcome the activation energy theoretically; E a is the activation energy, representing the energy barrier that the reactant molecules must overcome. The higher the activation energy, the more difficult the reaction is to proceed; R is the ideal gas constant; T is the absolute temperature; φ(C remaining ) is a function describing the influence of the remaining amount on the volatilization rate; ψ(C saturation ) is a function describing the influence of the saturation degree on the volatilization rate;

[0028] The function describing the influence of the remaining amount on the volatilization rate includes:

[0029]

[0030] where β is the coefficient controlling the degree of correction; n is the exponential parameter adjusting the sensitivity; C initial is the initial amount of substance; C remaining is the remaining amount of the substance;

[0031] The function describing the influence of the saturation degree on the volatilization rate includes:

[0032] ψ(C saturation ) = (1 - C saturation ) m

[0033] where C saturation is the saturation degree of the target substance in the current gas; m is the exponential parameter controlling the influence of the saturation degree on the rate.

[0034] Optionally, run the simulation software for simulation calculation to obtain the release amounts of key tobacco components in the tobacco section during the heating process of the heat-not-burn smoking device and the heat-not-burn cigarette, including:

[0035] Run the simulation software to calculate the distributions of the airflow field and the temperature field, and simulate the release process of tobacco components during the heating process of the heat-not-burn smoking device and the heat-not-burn cigarette;

[0036] Using the improved Arrhenius formula in the solver, solve for the release rate of key tobacco components in the tobacco section during the heating process to obtain the operation results;

[0037] Post-process the operation results to obtain the release amounts of key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process.

[0038] Optionally, the method further includes:

[0039] Compare the release amounts of key tobacco components in the tobacco section in the simulation calculation with the experimental results to verify the accuracy of the simulation calculation.

[0040] In a second aspect, the present application provides a simulation device for the heat and mass transfer process of a tobacco section, and the device includes:

[0041] A modeling unit for using 3D modeling software to establish a 3D geometric model of a heat-not-burn smoking device and a heat-not-burn cigarette;

[0042] A processing unit for performing mesh division processing on the 3D geometric model to obtain quality meshes;

[0043] A setting unit for importing the quality meshes into the simulation software and setting the solver of the simulation software according to the user-defined function UDF. The UDF includes a heat and mass transfer function of tobacco components in the tobacco section, a function of the suction condition, a function of simulating the filter tip retention effect, and a thermal property function of the tobacco section during the heating process. The heat release kinetic equation in the heat and mass transfer function is the improved Arrhenius formula;

[0044] An operation unit for running the simulation software to perform simulation calculations to obtain the release amounts of key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process.

[0045] Optionally, the processing unit specifically includes:

[0046] Divide the meshes of the heating body area in the 3D geometric model to obtain heating body meshes;

[0047] Divide the meshes of the gap space between the heating body area and the tobacco section in the 3D geometric model to obtain gap space meshes;

[0048] Divide the meshes of the tobacco section in the 3D geometric model to obtain tobacco section meshes;

[0049] Process the heating body meshes, gap space meshes, and tobacco section meshes in the form of coupled nodes to obtain quality meshes.

[0050] Optionally, the device further includes: An obtaining unit is used for:

[0051] Using the UDF program to set the heat and mass transfer function, the heat and mass transfer function includes the thermal decomposition and release kinetic equation of the material in the tobacco segment, the endothermic and exothermic function of the moisture phase change, and the glycerol endothermic effect function;

[0052] Using the UDF program to set the function of the suction condition and the function of simulating the filter tip retention effect;

[0053] The UDF program is used to set the thermal property function, which includes the function of the physical property parameters of the tobacco segment changing with temperature during the heating process.

[0054] Optionally, when the setting unit sets the solver of the simulation software according to the user-defined function UDF, it is specifically used to:

[0055] Select the unsteady model in the solver;

[0056] The thermal property function, the heat and mass transfer function, the function of the suction condition and the function of simulating the filter tip interception effect are loaded into the simulation software through the UDF program;

[0057] Coupling thermal property functions with the temperature field of the simulation software;

[0058] The heat and mass transfer function is set as the property parameters of the material in the tobacco segment, wherein the property parameters include the pyrolysis temperature and volatilization kinetic parameters of the material in the tobacco segment, the phase change characteristics of water, and the endothermic effect of glycerol;

[0059] The initial conditions and boundary conditions in the simulation software are set, wherein the initial conditions include the initial temperature of the tobacco segment and the heat transfer boundary conditions between the heating body surface and the tobacco segment, and the boundary conditions include the inlet flow rate and outlet pressure of the airflow field.

[0060] Optionally, a modified Arrhenius formula, including:

[0061]

[0062] Among them, k i is the volatilization rate of the i-th substance; A is the frequency factor, which indicates the number of times a reaction may occur per unit time and per unit volume if the reactant molecules have enough energy to overcome the activation energy in theory; E a is the activation energy, which indicates the energy barrier that the reactant molecules must overcome. The higher the activation energy, the more difficult the reaction is. R is the ideal gas constant. T is the absolute temperature. φ(C remaining ) describes the function of the residual amount on the volatilization rate; ψ(C saturation ) is a function describing the effect of saturation level on volatilization rate;

[0063] The function of the remaining amount on the evaporation rate includes:

[0064]

[0065] where β is the coefficient for controlling the correction degree; n is the exponential parameter for adjusting the sensitivity; C initial is the initial amount of substance; C remaining is the remaining amount of the substance;

[0066] The function of the saturation degree on the evaporation rate includes:

[0067] ψ(C saturation ) = (1 - C saturation ) m

[0068] where C saturation is the saturation degree of the target substance in the current gas; m is the exponential parameter for controlling the influence of the saturation degree on the rate.

[0069] Optionally, the operation unit is specifically configured to:

[0070] Run simulation software to calculate the distribution of the airflow field and the temperature field, and simulate the release process of tobacco components during the heating process of the heat-not-burn smoking device and the heat-not-burn cigarette;

[0071] Use the improved Arrhenius formula in the solver to solve the release rate of the key tobacco components in the tobacco section during the heating process, and obtain the operation result;

[0072] Perform post-processing on the operation result to obtain the release amount of the key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process.

[0073] Optionally, the device further includes: a verification unit for:

[0074] Compare the release amount of the key tobacco components in the tobacco section in the simulation calculation with the experimental results to verify the accuracy of the simulation calculation.

[0075] In a third aspect, the present application provides an electronic device, which includes a memory and a processor:

[0076] The memory is used to store a computer program;

[0077] The processor is used to execute the method provided in the first aspect according to the computer program.

[0078] In a fourth aspect, the present application provides a computer-readable storage medium, which is used to store a computer program, and the computer program is used to execute the method provided in the first aspect.

[0079] As can be seen, the present application has the following beneficial effects:

[0080] The present application provides a simulation method for the heat and mass transfer process of a tobacco section. First, a three-dimensional geometric model of a heat-not-burn smoking device and a heat-not-burn cigarette is established using three-dimensional modeling software, and the three-dimensional geometric model is subjected to mesh division processing to obtain a quality mesh. Then, the quality mesh is imported into the simulation software, and the solver of the simulation software is set according to a user-defined function (UDF). The UDF includes a heat and mass transfer function of the tobacco components in the tobacco section, a function of the suction condition, a function of simulating the filter tip interception effect, and a thermal property function of the tobacco section during the heating process. The heat release kinetic equation in the heat and mass transfer function is an improved Arrhenius formula. Finally, the simulation software is run for simulation calculation to obtain the release amounts of key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process.

[0081] In this process, the solver of the simulation software is set using the UDF program to realize the simulation of the heat and mass transfer of the tobacco section on the basis of saving experimental costs and improving research efficiency. Among them, the heat release kinetic equation being an improved Arrhenius formula can improve the accuracy of the change in the release amounts of key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process. Therefore, when running the simulation software for simulation calculation, solving the improved Arrhenius formula can accurately simulate the release amounts of key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process, thereby improving the simulation accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present application. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0083] Figure 1 It is a schematic flowchart of an embodiment of a simulation method for the heat and mass transfer process of a tobacco section in an embodiment of the present application;

[0084] Figure 2 It is a schematic structural diagram of a three-dimensional geometric model of a heat-not-burn smoking device and a heat-not-burn cigarette in an embodiment of the present application;

[0085] Figure 3 It is a schematic diagram of the simulation settings of a heat-not-burn smoking device and a heat-not-burn cigarette in an embodiment of the present application;

[0086] Figure 4Schematic flowchart of another embodiment of the simulation method for the heat and mass transfer process of a tobacco segment in an embodiment of the present application;

[0087] Figure 5 Schematic structural diagram of a simulation device for the heat and mass transfer process of a tobacco segment in an embodiment of the present application;

[0088] Figure 6 Schematic structural diagram of an electronic device in an embodiment of the present application. Detailed implementation manners

[0089] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present invention.

[0090] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in the present application are all information and data authorized by the user or fully authorized by all parties, and the collection, use, and processing of relevant data need to comply with the relevant laws, regulations, and standards of relevant countries and regions.

[0091] Currently, traditional experimental methods use standard heat-not-burn smoking devices and tobacco segments for experiments, and collect data such as the release amount of key tobacco components, airflow distribution, and temperature change during the heating process. However, the experimental method is not only cumbersome, but also requires high equipment investment and operation costs, and it is difficult to meet the research needs of high efficiency and accuracy.

[0092] In the embodiments of the present application, by using the UDF program to implement the simulation of heat and mass transfer of the tobacco segment, the physical property parameters and boundary conditions can be dynamically adjusted according to the temperature change during the heating process, thereby improving the simulation accuracy. Moreover, the computer simulation method can save experimental costs and improve research efficiency.

[0093] In specific implementation, the method may include, for example: First, use 3D modeling software to establish 3D geometric models of the heat-not-burn smoking device and the heat-not-burn cigarette, and perform mesh division processing on the 3D geometric models to obtain quality meshes; then import the quality meshes into the simulation software, and set the solver of the simulation software according to the user-defined function (UDF). The UDF includes the heat and mass transfer function of the tobacco components in the tobacco section, the function of the suction condition, the function of simulating the filter tip interception effect, and the thermal property function of the tobacco section during the heating process. The heat release kinetic equation in the heat and mass transfer function is the improved Arrhenius formula; finally, run the simulation software to perform simulation calculations to obtain the release amounts of the key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process.

[0094] It can be seen that the method provided by the embodiment of the present application uses the UDF program to set the solver of the simulation software, so as to realize the simulation of heat and mass transfer in the tobacco section on the basis of saving experimental costs and improving research efficiency. Among them, the heat release kinetic equation being the improved Arrhenius formula can improve the accuracy of the change in the release amounts of the key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process. Therefore, when running the simulation software to perform simulation calculations, solving the improved Arrhenius formula can accurately simulate the release amounts of the key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process, thereby improving the simulation accuracy.

[0095] To facilitate the understanding of the specific implementation of the simulation method for the heat and mass transfer process of the tobacco section provided by the embodiment of the present application, the following will be described in conjunction with the accompanying drawings.

[0096] It should be noted that the main body implementing the simulation method for the heat and mass transfer process of the tobacco section may be the simulation device for the heat and mass transfer process of the tobacco section provided by the embodiment of the present application. The simulation device for the heat and mass transfer process of the tobacco section may be carried on an electronic device or a functional module of an electronic device. The electronic device in the embodiment of the present application may be any device capable of implementing the simulation method for the heat and mass transfer process of the tobacco section in the embodiment of the present application, for example, it may be an Internet of Things (IoT) device.

[0097] Figure 1 It is a schematic flowchart of a simulation method for the heat and mass transfer process of a tobacco section provided by an embodiment of the present application. The method can be applied to a simulation device for the heat and mass transfer process of a tobacco section. The simulation device for the heat and mass transfer process of a tobacco section may be, for example, the simulation device 500 for the heat and mass transfer process of a tobacco section as shown in Figure 5 shown, or the simulation device for the heat and mass transfer process of a tobacco section may also be integrated in Figure 6Functional modules in the electronic device 600 shown

[0098] As shown in Figure 1 the method includes the following S101 - S103:

[0099] S101: Use 3D modeling software to establish 3D geometric models of the heat - not - burn smoking device and the heat - not - burn cigarette, and perform mesh division processing on the 3D geometric models to obtain quality meshes.

[0100] In order to obtain the release amount of key tobacco components in the tobacco section during the heating process of the heat - not - burn smoking device, first use 3D modeling software to establish 3D geometric models of the heat - not - burn smoking device and the heat - not - burn cigarette, and perform mesh division processing on the 3D geometric models to obtain quality meshes; then import the quality meshes into the simulation software, and set the solver of the simulation software according to the user - defined function UDF; finally, run the simulation software for simulation calculation to obtain the release amount of key tobacco components in the tobacco section of the heat - not - burn smoking device and the heat - not - burn cigarette during the heating process. Therefore, this application uses S101 to obtain quality meshes, making a preliminary preparation for subsequent simulation.

[0101] As an example, S101 may include: using 3D modeling software to establish 3D geometric models of the heat - not - burn smoking device and the heat - not - burn cigarette. The subsequent process of mesh division includes: dividing the mesh of the heating body area in the 3D geometric model to obtain the heating body mesh; then dividing the mesh of the gap space between the heating body area and the tobacco section in the 3D geometric model to obtain the gap space mesh; dividing the mesh of the tobacco section in the 3D geometric model to obtain the tobacco section mesh; and processing the heating body mesh, the gap space mesh, and the tobacco section mesh in the form of coupled nodes to obtain quality meshes.

[0102] When establishing the 3D geometric models of the heat - not - burn smoking device and the heat - not - burn cigarette using the above - mentioned 3D modeling software, it can be constructed as Figure 2 shown, constructing the Yanker heating device and the heated cigarette (dry substrate), and when constructing, it is necessary to consider the geometric shapes of the heating element and the tobacco section and their interactions, so as to accurately describe the geometric shapes and structures of the Yanker heating device and the tobacco section.

[0103] During the above - mentioned mesh division process, in order to ensure the simulation accuracy, the quality of the divided meshes is detected, and the "Element Quality" tool is used to evaluate the element quality to ensure that the meshes meet the calculation requirements, so as to ensure the accuracy of the subsequent simulation results.

[0104] During this process, a three-dimensional simulation model of the heat-not-burn smoking device and the heat-not-burn cigarette is specifically designed. By meshing the heating appliance and the heat-not-burn cigarette and combining with the UDF program to dynamically load and adjust various physical parameters during the heating process, the simulation accuracy is optimized.

[0105] S102: Import the quality grid into the simulation software, and set the solver of the simulation software according to the user-defined function UDF. The UDF includes the heat and mass transfer function of the tobacco components in the tobacco section, the function of the suction condition, the function of simulating the filter retention effect, and the thermal property function of the tobacco section during the heating process. The thermal decomposition release kinetic equation in the heat and mass transfer function is the improved Arrhenius formula.

[0106] As an example, the embodiments of the present application pre-construct the required user-defined function UDF. That is, during the simulation process, the temperature, air flow, and the heat and mass transfer process of substances need to be accurately modeled through the user-defined function (UDF). The UDF specifically includes the following:

[0107] (1) First, use the UDF program to set the heat and mass transfer function, which can specifically include: ① The thermal decomposition release kinetic equation of the materials in the tobacco section, that is, construct the UDF of the thermal decomposition release kinetics of nicotine, moisture, and glycerol. This part of the function involves the thermal decomposition and volatilization process of tobacco components. According to the thermal decomposition temperature and release kinetic characteristics of different substances, the dynamic release of tobacco components is simulated; ② The endothermic and exothermic function of moisture phase change, that is, construct the UDF of the endothermic and exothermic of moisture phase change. Considering the phase change effect of moisture, the influence of the evaporation and condensation of moisture on the temperature field during the heating process, the endothermic and exothermic function of moisture phase change can dynamically adjust the endothermic and exothermic processes of moisture phase change; ③ The glycerol endothermic effect function, that is, construct the UDF of the glycerol endothermic effect. Glycerol absorbs heat during the heating process, and this effect needs to be simulated through the UDF to accurately reflect the energy transfer and material changes during the heating process.

[0108] (2) Then use the UDF program to set the function of the suction condition and the function of simulating the filter retention effect, which can specifically include: ① Construct the UDF of simulating the suction condition: By setting parameters such as the suction speed and air flow distribution, simulate the inhalation condition when the smoking device is actually used to reproduce the air flow field distribution in actual use; ② Construct the UDF of simulating the filter retention effect: Simulate the retention effect of the smoke when passing through the filter, which affects the changes in the smoke components and their release amounts.

[0109] (3) Finally, use the UDF program to set the thermophysical property function. The thermophysical property function includes the function of the variation of the physical property parameters of the tobacco segment with temperature during the heating process. Specifically, it can include: constructing a UDF for physical property parameters varying with temperature: This part of the function can dynamically adjust the thermophysical property parameters of the tobacco segment, such as thermal conductivity, specific heat capacity, density, etc., to accurately reflect the influence of temperature change on the heating process.

[0110] As an example, after constructing the relevant UDF, the solver of the simulation software can be set according to the user-defined function UDF. The specific process can include: (1) Select the unsteady-state model in the solver; (2) Load the thermophysical property function, heat and mass transfer function, function of the suction condition, and function of simulating the filter tip retention effect into the simulation software through the UDF program; (3) Couple the thermophysical property function with the temperature field of the simulation software; (4) Set the heat and mass transfer function as the property parameters of the material in the tobacco segment. The property parameters include the pyrolysis temperature and volatile kinetics parameters of the material in the tobacco segment, the phase change characteristics of water, and the endothermic effect of glycerol; (5) Set the initial conditions and boundary conditions in the simulation software. The initial conditions include the initial temperature of the tobacco segment and the heat transfer boundary condition between the heating body surface and the tobacco segment. The boundary conditions include the inlet flow rate of the airflow field and the outlet pressure.

[0111] The reason for selecting the unsteady-state model in the solver settings is that the simulation software in this application is a time-related system, so the unsteady-state (transient) model is selected.

[0112] It should be noted that the simulation software in the embodiments of this application can be ANSYS software. The steps of loading the UDF into the simulation software can specifically include: First, enter the Fluent function custom module, select the compilation function in "Function", click "Add", select and add the above-mentioned multiple set UDFs item by item. After adding, click "Build" and "Load" to complete the loading of the set UDF. Subsequently, it can also be selected whether other common simulation parameters need to be set through the UDF. If needed, open the corresponding parameter setting interface and add the corresponding UDF to the control parameters. If not, set the parameters manually. During this process, each functional module is seamlessly integrated into the simulation model to ensure its correct execution. Among them, the UDF is written in C language and is a user-written program. It can be dynamically connected to the Fluent solver to improve the solver performance and control some model parameters or calculation processes during the Fluent calculation.

[0113] During the heating process of heat-not-burn tobacco devices and heat-not-burn cigarettes, physical properties (such as thermal conductivity, specific heat capacity, density, etc. of tobacco) will change with temperature, so it is necessary to load dynamic physical property parameters through the UDF program. Specifically, it is necessary to couple the thermal property function with the temperature field of the simulation software to ensure that the corresponding physical property parameters can be accurately reflected in the simulation when the temperature changes.

[0114] Based on the simulation requirements, all the required materials are newly created, and detailed physical and chemical parameters are set for each material, that is, the heat and mass transfer functions are set as the property parameters of the materials in the tobacco segment, that is, the initial state and phase change point of the tobacco components are set. Therefore, the property parameters include the pyrolysis temperature and volatilization kinetic parameters of the materials in the tobacco segment, the phase change characteristics of water and the endothermic effect of glycerol, to ensure that the simulation process can accurately reflect the physical phenomena in the actual heating process.

[0115] In the simulation, in order to ensure consistency with the actual situation, it is necessary to set reasonable boundary conditions and initial conditions, where the initial conditions include the initial temperature of the tobacco segment and the heat transfer boundary conditions between the heating body surface and the tobacco segment, and the heat transfer boundary conditions include: the heat transfer coefficient between geometric bodies, the heat transfer coefficient between the geometric body and the environment, and the temperature of the external environment; boundary conditions include the inlet flow rate and outlet pressure of the airflow field, etc. By setting these conditions, it is ensured that the simulation can truly reflect the heat conduction, material diffusion and airflow dynamics during actual use. Finally, after the mass mesh of the processed three-dimensional geometric model of the heat-not-burn tobacco device and the heat-not-burn cigarette is set up through the solver settings, the specific UDF action positions and boundary positions can be reflected in the mass mesh, for example Figure 3 Diagram of the simulation solver setup shown.

[0116] In this process, by developing and applying a user-defined function (UDF) program, the heat and mass transfer process of the tobacco segment during the heating process of the heat-not-burn tobacco device and the heat-not-burn cigarette is accurately simulated, solving the current problem of being unable to dynamically adjust the physical property parameters with temperature changes. And based on the dynamic adjustment of the physical property parameters with temperature changes, the heat and mass transfer processes such as pyrolysis, volatilization and diffusion of the tobacco segment are simulated using the UDF program to ensure the accuracy and authenticity of the simulation results, and by establishing a coupled simulation model of the airflow field and the temperature field, the present invention can simulate the influence of the heating body, the tobacco device and the suction condition on the heating process of the tobacco segment, providing a comprehensive simulation analysis tool, and finally by constructing multiple custom functions UDF, including the pyrolysis kinetic equations of materials, moisture, and glycerin in the tobacco segment, the functions of simulating the moisture phase change and glycerin endothermic process, and the filter interception effect, the accurate simulation of the whole process of the release of key tobacco components in the tobacco segment during the heating process of the heat-not-burn tobacco device and the heat-not-burn cigarette is realized.

[0117] S103: Run the simulation software to perform simulation calculations and obtain the release amounts of key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process.

[0118] As an example, S103 may include: running the simulation software to calculate the distributions of the airflow field and the temperature field, simulating the release process of tobacco components in the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process; using the improved Arrhenius formula in the solver to solve the release rate of the key tobacco components in the tobacco section during the heating process to obtain the operation result; and performing post-processing on the operation result to obtain the release amounts of the key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process.

[0119] After completing the above settings for the solver, simulation calculations can be performed. First, calculate the distributions of the airflow field and the temperature field through CFD simulation software, simulate the release process of tobacco components during the heating process, and track the changes in the temperature field and the airflow field in real time. Then, use the improved Arrhenius formula in the solver to solve the release rate of the key tobacco components (such as moisture, nicotine, glycerol, etc.) in the tobacco section during the heating process to obtain the influence of the airflow field and the temperature field on the release of the key tobacco components in the tobacco section, thereby obtaining the operation result. Finally, perform post-processing on the operation result to obtain the release amounts of the key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process. During this process, further analysis can also be carried out on the airflow, temperature, and release characteristics of the key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette under different working conditions, providing a basis for the design optimization of the heat-not-burn smoking device and the heat-not-burn cigarette.

[0120] The above improved Arrhenius formula is specifically shown as formula (1):

[0121]

[0122] where k i is the volatilization rate of the i-th substance; A is the frequency factor, indicating the number of possible reactions per unit time and unit volume when the reactant molecules have sufficient energy to overcome the activation energy theoretically; E a is the activation energy, representing the energy barrier that the reactant molecules must overcome. The higher the activation energy, the more difficult the reaction is to proceed; R is the ideal gas constant; T is the absolute temperature; φ(C remaining ) is a function describing the influence of the remaining amount on the volatilization rate; ψ(C saturation ) is a function describing the influence of the saturation degree on the volatilization rate.

[0123] The function describing the influence of the remaining amount on the volatilization rate, that is, the correction coefficient of the substance remaining amount, is specifically shown as formula (2):

[0124]

[0125] Among them, β is the coefficient for controlling the degree of correction; n is the exponential parameter for adjusting the sensitivity; C initial is the initial amount of substance; C remaining is the remaining amount of the substance;

[0126] The function of the influence of the saturation degree on the volatilization rate, that is, the correction coefficient of the gas saturation degree, and the specific formula is shown in formula (3):

[0127] ψ(C saturation ) = (1 - C saturation ) m Formula (3)

[0128] Among them, C saturation is the saturation degree of the target substance in the current gas; m is the exponential parameter for controlling the influence of the saturation degree on the rate.

[0129] The implementation of the improved Arrhenius formula dynamic feedback mechanism includes:

[0130] First, calculate the remaining amount in real time: In each time step, update the remaining amount according to the current volatilization rate, and the specific formula is shown in formula (4):

[0131]

[0132] Among them, t is the time, and Δt is the time step.

[0133] Secondly, calculate the gas saturation degree: Calculate according to the ratio of the gas concentration in the volume to the saturation concentration, and the specific formula is shown in formula (5):

[0134]

[0135] Among them, C sat is the gas saturation concentration; C gas is the gas concentration.

[0136] Finally, update the volatilization rate: Introduce the above-mentioned correction coefficient through the formula, so as to calculate the new volatilization rate, in order to improve the accuracy of the change in the release amount of key tobacco components in the tobacco section during the heating process of the heat-not-burn smoking device and the heat-not-burn cigarette.

[0137] In addition, the embodiments of the present application can also compare the release amounts of key tobacco components in the tobacco section obtained through simulation calculations with the experimental results to verify the accuracy of the proposed simulation calculations. The specific process may include: First, use a standard heat-not-burn smoking device and a tobacco section for experiments, and collect data such as the release amounts of key tobacco components, air flow distribution, and temperature changes in the tobacco section during the experiments; when the release amounts of key tobacco components in the tobacco section in the simulation calculations are consistent with the actual measurement results, it ensures the high precision and feasibility of the simulation calculation method, and has significant advantages in reducing experimental costs and improving efficiency. Therefore, it further confirms the application value of the simulation calculation method proposed by the embodiments of the present application in the design and performance evaluation of heat-not-burn smoking devices and heat-not-burn cigarettes.

[0138] It can be seen that the embodiments of the present application use the UDF program to implement the simulation of heat and mass transfer in the tobacco section, and can dynamically adjust the physical property parameters and boundary conditions according to the temperature changes during the heating process, thereby improving the simulation accuracy and overcoming the limitation in the traditional method that it cannot accurately reflect the influence of temperature changes on the physical property parameters. And in the present application, the simulation software is easy to operate and highly flexible, and can set parameters according to different experimental requirements, reducing the technical threshold of the experimental process, and can also save experimental costs and improve research efficiency. In the present application, the improved Arrhenius formula is used as the thermal decomposition release kinetic equation, which can accurately simulate the influence of the air flow field and temperature field on the release of key tobacco components in the tobacco section, thereby enhancing the simulation stability and improving the simulation accuracy.

[0139] To make the method provided by the embodiments of the present application clearer and easier to understand, the following Figure 4 illustrates a specific example of the method.

[0140] As Figure 4 shown, this embodiment may include the following S401 to S412:

[0141] S401: Use 3D modeling software to establish a 3D geometric model of the heat-not-burn smoking device and the cigarette.

[0142] In the embodiments of the present application, Yanker software is used to construct a simulation model of the heat-not-burn smoking device and the heat-not-burn cigarette, including the Yanker heating appliance and the heated cigarette (dry substrate). The constructed 3D geometric model can be as Figure 2 shown, and will not be specifically described here.

[0143] S402: Perform mesh division processing on the 3D geometric model to obtain quality meshes.

[0144] In the embodiments of the present application, when performing mesh division processing on a three-dimensional geometric model, the mesh of the heating body region in the three-dimensional geometric model can be first divided to obtain the heating body mesh; the mesh of the gap space between the heating body region and the tobacco section in the three-dimensional geometric model is divided to obtain the gap space mesh; then the mesh of the tobacco section in the three-dimensional geometric model is divided to obtain the tobacco section mesh; finally, in the form of coupled nodes, the heating body mesh, the gap space mesh, and the tobacco section mesh are processed to obtain the quality mesh.

[0145] And to further ensure the simulation accuracy, the mesh quality is detected, and the "Element Quality" tool is used to evaluate the element quality to ensure that the mesh meets the calculation requirements.

[0146] In this process, by performing mesh division on the heating body and the cigarette rod, it is convenient to dynamically load and adjust various physical parameters during the heating process subsequently.

[0147] S403: Use the UDF program to set the heat and mass transfer function, and the heat and mass transfer function includes the thermal decomposition release kinetic equation of the material in the tobacco section, the endothermic and exothermic function of water phase change, and the glycerol endothermic effect function. The thermal decomposition release kinetic equation is the improved Arrhenius formula.

[0148] During the simulation process, the UDF (User-Defined Function) program is used to model multiple physical processes. First, the thermal decomposition release kinetic equation of the material in the tobacco section is set. In the embodiments of the present application, the improved Arrhenius formula is used as the thermal decomposition release kinetic equation, which can accurately simulate the influence of the airflow field and temperature field on the release of key tobacco components in the tobacco section, thereby enhancing the simulation stability and improving the simulation accuracy. Then, the endothermic and exothermic function of water phase change is set to simulate the phase change behavior of the water in the tobacco section during the heating process. Finally, the glycerol endothermic effect function is set to simulate the endothermic effect of glycerol during the heating process.

[0149] S404: Use the UDF program to set the function of the suction condition and the function of simulating the filter tip interception effect.

[0150] The present application constructs the UDF for simulating the airflow field and temperature field during the smoking process, and constructs the UDF for the interaction between the filter tip and the airflow.

[0151] S405: Use the UDF program to set the thermophysical property function, and the thermophysical property function includes the function of the change of the physical property parameters of the tobacco section with temperature during the heating process.

[0152] The present application constructs the change of the physical property parameters (such as thermal conductivity, specific heat capacity, density, etc.) of the tobacco section with temperature during the heating process to ensure the dynamic adjustment of the physical property parameters during the simulation process.

[0153] In this application, by constructing multiple custom functions UDF, accurate simulation of the entire process of releasing key tobacco components in the tobacco segment of heat-not-burn tobacco devices and heat-not-burn cigarettes during the heating process is achieved.

[0154] S406: Import the mass mesh into the simulation software and select the unsteady model in the solver.

[0155] The mass grid obtained above is imported into the simulation software, and since the simulation of this application is a time-dependent process, a non-steady-state (transient) model is selected.

[0156] S407: Loading the thermal property function, the heat and mass transfer function, the function of the suction condition and the function of simulating the filter tip retention effect into the simulation software through the UDF program.

[0157] In the embodiment of the present application, the UDF constructed above is loaded into the simulation software through the UDF program. The specific loading process is shown in the above embodiment and will not be repeated here. The embodiment of the present application develops and applies the UDF program to accurately simulate the heat and mass transfer process of the tobacco segment of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process.

[0158] S408: The thermal property function is coupled with the temperature field of the simulation software, and the heat and mass transfer function is set as the property parameters of the material in the tobacco segment, wherein the property parameters include the pyrolysis temperature and volatilization kinetic parameters of the material in the tobacco segment, the phase change characteristics of water, and the endothermic effect of glycerol.

[0159] In order to simulate the entire heating process of heat-not-burn tobacco devices and heat-not-burn cigarettes in the future, the thermal property function is coupled with the temperature field in the simulation model through the UDF program to ensure that the corresponding physical property parameters can be accurately reflected in the simulation when the temperature changes. It is also necessary to set the initial state and phase change point of the tobacco components, that is, to set the property parameters of the materials in the tobacco segment. Therefore, the heat and mass transfer functions are set as the property parameters of the materials in the tobacco segment to ensure that the simulation results are highly realistic.

[0160] S409: Setting initial conditions and boundary conditions in the simulation software, wherein the initial conditions include the initial temperature of the tobacco segment and the heat transfer boundary conditions between the heating body surface and the tobacco segment, and the boundary conditions include the inlet flow rate and outlet pressure of the airflow field.

[0161] In order to ensure that the simulation process conforms to the actual situation, reasonable boundary conditions and initial conditions need to be set in the embodiments of the present application. Specifically, the initial temperature of the tobacco section and the heat transfer boundary conditions between the heating element surface and the tobacco section can be set, as well as the inlet flow velocity and outlet pressure of the airflow field. Through the setting of these conditions in the embodiments of the present application, it is ensured that the simulation can truly reflect the heat conduction, mass diffusion, and airflow dynamics in the actual use process.

[0162] S410: Run the simulation software to calculate the distribution of the airflow field and temperature field, and use the improved Arrhenius formula in the solver to solve the release rate of key tobacco components in the tobacco section during the heating process, and obtain the operation result.

[0163] After the above settings are completed, the simulation software can be run to calculate the distribution of the airflow field and temperature field, and the Arrhenius formula can be solved to calculate the release rate of key tobacco components in the tobacco section during the heating process, and obtain the operation result.

[0164] S411: Post-process the operation result to obtain the release amount of key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process.

[0165] S412: Compare the release amount of key tobacco components in the tobacco section in the simulation calculation with the experimental results to verify the accuracy of the simulation calculation.

[0166] By comparing the experimental results and the simulation data, the accuracy and reliability of the simulation calculation can be verified. Thus, the high precision and feasibility of the simulation method are ensured, and it has significant advantages in reducing experimental costs and improving efficiency.

[0167] This embodiment provides a simulation method for the heat and mass transfer process of a tobacco section. Using UDF to perform heat and mass transfer simulation on a heat-not-burn cigarette can not only save experimental costs, but also improve research efficiency and obtain more accurate results through computer program operations. Moreover, the simulation method and UDF program proposed in the embodiments of the present application can be used as tools for the design and optimization of heat-not-burn smoking devices and heat-not-burn cigarettes, helping to improve the performance of products, optimize the release characteristics of tobacco section components, and thus improve the user experience of heat-not-burn smoking devices.

[0168] See Figure 5 , this embodiment of the present application provides a simulation device 500 for the heat and mass transfer process of a tobacco section. The device includes:

[0169] A modeling unit 501, configured to establish a three-dimensional geometric model of a heat-not-burn smoking device and a heat-not-burn cigarette using three-dimensional modeling software;

[0170] A processing unit 502, configured to perform mesh division processing on a three-dimensional geometric model to obtain a quality mesh;

[0171] A setting unit 503, configured to import the quality mesh into a simulation software, and set a solver of the simulation software according to a user-defined function UDF, where the UDF includes a heat and mass transfer function of tobacco components in a tobacco section, a function of a puffing condition, a function of simulating a filter retention effect, and a thermal property function of the tobacco section during the heating process, and a thermal decomposition release kinetic equation in the heat and mass transfer function is a modified Arrhenius formula;

[0172] An operation unit 504, configured to run the simulation software to perform simulation calculations to obtain release amounts of key tobacco components in the tobacco section of a heat-not-burn smoking device and a heat-not-burn cigarette during the heating process.

[0173] Optionally, the processing unit 502 specifically includes:

[0174] Dividing the mesh of the heating body region in the three-dimensional geometric model to obtain a heating body mesh;

[0175] Dividing the mesh of the gap space between the heating body region and the tobacco section in the three-dimensional geometric model to obtain a gap space mesh;

[0176] Dividing the mesh of the tobacco section in the three-dimensional geometric model to obtain a tobacco section mesh;

[0177] Processing the heating body mesh, the gap space mesh, and the tobacco section mesh in a form of coupled nodes to obtain a quality mesh.

[0178] Optionally, the device 500 further includes: An obtaining unit is configured to:

[0179] Setting the heat and mass transfer function by using a UDF program, where the heat and mass transfer function includes a thermal decomposition release kinetic equation of materials in the tobacco section, an endothermic and exothermic function of moisture phase change, and a glycerol endothermic effect function;

[0180] Setting the function of the puffing condition and the function of simulating the filter retention effect by using a UDF program;

[0181] Setting the thermal property function by using a UDF program, where the thermal property function includes a function of the change of physical property parameters of the tobacco section with temperature during the heating process.

[0182] Optionally, when the setting unit 503 sets the solver of the simulation software according to the user-defined function UDF, it is specifically configured to:

[0183] Selecting an unsteady state model in the solver;

[0184] Load the functions of thermal properties, heat and mass transfer, suction conditions, and the function simulating the filter tip interception effect into the simulation software through a UDF program;

[0185] Couple the function of thermal properties with the temperature field of the simulation software;

[0186] Set the heat and mass transfer function as the property parameters of the materials in the tobacco section, and the property parameters include the pyrolysis temperature and volatile kinetic parameters of the materials in the tobacco section, the phase change characteristics of water, and the endothermic effect of glycerol;

[0187] Set the initial conditions and boundary conditions in the simulation software. The initial conditions include the initial temperature of the tobacco section and the heat transfer boundary conditions between the heating element surface and the tobacco section, and the boundary conditions include the inlet flow rate and outlet pressure of the air flow field.

[0188] Optionally, the improved Arrhenius formula includes:

[0189]

[0190] where k i is the volatilization rate of the i-th substance; A is the frequency factor, indicating the number of possible reactions per unit time and unit volume if the reactant molecules have enough energy to overcome the activation energy theoretically; E a is the activation energy, representing the energy barrier that the reactant molecules must overcome. The higher the activation energy, the more difficult the reaction is to proceed; R is the ideal gas constant; T is the absolute temperature; φ(C remaining ) is the function describing the influence of the remaining amount on the volatilization rate; ψ(C saturation ) is the function describing the influence of the saturation degree on the volatilization rate;

[0191] The function describing the influence of the remaining amount on the volatilization rate includes:

[0192]

[0193] where β is the coefficient controlling the correction degree; n is the exponential parameter adjusting the sensitivity; C initial is the initial amount of substance; C remaining is the remaining amount of the substance;

[0194] The function describing the influence of the saturation degree on the volatilization rate includes:

[0195] ψ(C saturation )=(1 - C saturation ) m

[0196] where C saturationis the saturation degree of the target substance in the current gas; m is an exponential parameter that controls the influence of the saturation degree on the rate.

[0197] Optionally, the running unit 504 is specifically configured to:

[0198] Run simulation software to calculate the distribution of the airflow field and the temperature field, and simulate the release process of tobacco components during the heating process of the heat-not-burn smoking device and the heat-not-burn cigarette;

[0199] Use the improved Arrhenius formula in the solver to solve the release rate of key tobacco components in the tobacco section during the heating process, and obtain the operation result;

[0200] Post-process the operation result to obtain the release amounts of key tobacco components in the tobacco section of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process.

[0201] Optionally, the device further includes: a verification unit for:

[0202] Compare the release amounts of key tobacco components in the tobacco section in the simulation calculation with the experimental results to verify the accuracy of the simulation calculation.

[0203] It should be noted that for the specific implementation manner and achieved effects of the simulation device 500 for the heat and mass transfer process of the tobacco section, reference can be made to the relevant descriptions in the above Figure 1 or Figure 4 provided method, which will not be elaborated here.

[0204] An embodiment of the present application also provides an electronic device 600, as Figure 6 shown, the device 600 includes a memory 601 and a processor 602:

[0205] The memory 601 is used to store a computer program;

[0206] The processor 602 is configured to execute the above Figure 1 or Figure 4 provided method according to the computer program.

[0207] In addition, the present application also provides a computer-readable storage medium, and the computer-readable storage medium is used to store a computer program, and the computer program is used to execute Figure 1 or Figure 4 the provided method.

[0208] As can be seen from the description of the above embodiments, those skilled in the art can clearly understand that all or part of the steps in the above-described embodiment methods can be implemented by means of software plus a general-purpose hardware platform. Based on such an understanding, the technical solution of the present application can be embodied in the form of a software product, and the computer software product can be stored in a storage medium, such as read-only memory (ROM) / RAM, magnetic disk, optical disk, etc., including several instructions for causing a computer device (which may be a personal computer, a server, or a network communication device such as a router) to execute the methods described in various embodiments or certain parts of the embodiments of the present application.

[0209] Each embodiment in this specification is described in a progressive manner, and the same or similar parts among the embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments. In particular, for the device embodiments, since they are basically similar to the method embodiments, they are described relatively simply, and the relevant parts can be referred to the partial description of the method embodiments. The device embodiments described above are only illustrative. The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the objectives of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative effort.

[0210] The above description is only an exemplary embodiment of the present application and is not used to limit the protection scope of the present application.

Claims

1. A method for simulating heat and mass transfer in tobacco segments, characterized in that: The method comprises: Using 3D modeling software to establish a 3D geometric model of the heat-not-burn smoking device and the heat-not-burn cigarette, and performing network division processing on the 3D geometric model to obtain a quality mesh; The mass grid is imported into a simulation software, and a solver of the simulation software is set according to a user-defined function (UDF), wherein the UDF includes a heat and mass transfer function of tobacco components in a tobacco segment, a function of a suction condition, a function simulating a filter retention effect, and a thermal property function of the tobacco segment during a heating process, and the thermal decomposition release kinetic equation in the heat and mass transfer function is an improved Arrhenius formula; The simulation software is run to perform simulation calculations to obtain the release amounts of key tobacco components of the tobacco segments of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process.

2. The method according to claim 1, characterized in that The three-dimensional geometric model is subjected to a network division process to obtain a quality mesh, including: Dividing the grid of the heating body region in the three-dimensional geometric model to obtain a heating body grid; Dividing the gap space between the heating body area and the tobacco segment in the three-dimensional geometric model into a grid to obtain a gap space grid; Dividing the mesh of the tobacco segment in the three-dimensional geometric model to obtain a tobacco segment mesh; The heating body grid, the gap space grid and the tobacco segment grid are processed in the form of coupling nodes to obtain the mass grid.

3. The method according to claim 1, characterized in that The process of obtaining the user-defined function UDF includes: The heat and mass transfer function is set by using a UDF program, wherein the heat and mass transfer function includes a thermal decomposition and release kinetic equation of the material in the tobacco segment, an endothermic and exothermic function of a moisture phase change, and a glycerol endothermic effect function; Using the UDF program to set the function of the suction condition and the function of simulating the filter tip retention effect; The thermal property function is set by using the UDF program, and the thermal property function includes a function of how the physical property parameters of the tobacco segment change with temperature during the heating process.

4. The method according to claim 3, characterized in that: The solving method of the simulation software is set according to the user-defined function UDF, including: selecting an unsteady state model in the solver; The thermal property function, the heat and mass transfer function, the function of the suction condition and the function of simulating the filter retention effect are loaded into the simulation software through the UDF program; Coupling the thermal property function with the temperature field of the simulation software; The heat and mass transfer function is set as the property parameters of the material in the tobacco segment, wherein the property parameters include the pyrolysis temperature and volatilization kinetic parameters of the material in the tobacco segment, the phase change characteristics of water, and the endothermic effect of glycerol; The initial conditions and boundary conditions in the simulation software are set, wherein the initial conditions include the initial temperature of the tobacco segment and the heat transfer boundary conditions between the heating body surface and the tobacco segment, and the boundary conditions include the inlet flow rate and outlet pressure of the airflow field.

5. The method according to claim 1, characterized in that The improved Arrhenius formula includes: Among them, k i is the volatilization rate of the i-th substance; A is the frequency factor, which indicates the number of times a reaction may occur per unit time and per unit volume if the reactant molecules have enough energy to overcome the activation energy in theory; E a is the activation energy, which indicates the energy barrier that the reactant molecules must overcome. The higher the activation energy, the more difficult the reaction is. R is the ideal gas constant. T is the absolute temperature. φ(C remaining ) describes the function of the residual amount on the volatilization rate; ψ(C saturation ) is a function describing the effect of saturation level on volatilization rate; The function of the effect of the residual amount on the volatilization rate includes: Among them, β is the coefficient of controlling the degree of correction; n is the exponential parameter for adjusting sensitivity; C initial is the initial mass; C remaining is the remaining amount of the substance; The function of the effect of the saturation degree on the volatilization rate includes: ψ(C saturation )=(1-C saturation ) m Among them, C saturation is the saturation degree of the target substance in the current gas; m is the exponential parameter that controls the effect of the saturation degree on the rate.

6. The method according to claim 1, characterized in that The running of the simulation software to perform simulation calculations to obtain the release amounts of key tobacco components of the tobacco segments of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process includes: Running the simulation software to calculate the distribution of the airflow field and the temperature field, and simulating the release process of the tobacco components of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process; Using the improved Arrhenius formula in the solver, solving the release rate of the key tobacco components of the tobacco segment during the heating process to obtain the operation result; The operation results are post-processed to obtain the release amounts of key tobacco components of the tobacco segments of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process.

7. The method according to claim 1, characterized in that The method further comprises: The release amounts of key tobacco components of the tobacco segments in the simulation calculations were compared with the experimental results to verify the accuracy of the simulation calculations.

8. A device for simulating heat and mass transfer in tobacco segments, characterized in that: The device comprises: A modeling unit, used to establish a three-dimensional geometric model of a heat-not-burn smoking device and a heat-not-burn cigarette using a three-dimensional modeling software; A processing unit, used for performing network division processing on the three-dimensional geometric model to obtain a quality mesh; A setting unit, used for importing the mass grid into a simulation software, and setting a solver of the simulation software according to a user-defined function UDF, wherein the UDF includes a heat and mass transfer function of tobacco components in a tobacco segment, a function of a suction condition, a function simulating a filter retention effect, and a thermal property function of the tobacco segment during a heating process, wherein the thermal decomposition release kinetic equation in the heat and mass transfer function is an improved Arrhenius formula; The operation unit is used to run the simulation software to perform simulation calculations to obtain the release amounts of key tobacco components of the tobacco segments of the heat-not-burn smoking device and the heat-not-burn cigarette during the heating process.

9. An electronic device, characterized in that: The device includes a memory and a processor, and the processor is used to execute a program stored in the memory to run the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store a computer program, and the computer program is used to execute the method according to any one of claims 1 to 7.

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