Temperature field analysis method for particle type heated cigarette smoke flow heat transfer characteristics

Abstract

The invention discloses a temperature field analysis method for particle type heating cigarette smoke flow heat transfer characteristics, and relates to the field of novel tobacco product basic research, the method can accurately simulate smoke flow field and temperature field distribution, and the method comprises the following steps: S1, establishing a particle type heating cigarette smoke flow scene geometric model; s2, after grid division is conducted on the model, pressure drop and heat transfer equations of different functional sections of the cigarette are built through a finite element analysis method, and a smoking time period equation and a heating temperature equation are built through a UDF function; s3, setting physical property parameters of the porous medium and related boundary conditions of heating temperature and suction pressure; s4, simulation calculation is carried out, the smoke velocity and pressure simulation result of the axial center line of the cigarette is obtained, and after the effectiveness of the model is verified through linear fitting, the temperature field and flow field distribution of the cigarette is obtained through the model. The invention provides a reliable analysis means for the related research of the granular heating cigarette.

Description

Technical Field

[0001] This invention relates to the field of basic research on novel tobacco products, specifically a numerical simulation method for the heat transfer characteristics of particulate heated cigarette smoke flow. Background Technology

[0002] Currently, simulations of cigarette flow and heat transfer mainly focus on traditional iQOS-like sheet tobacco material smoldering simulation, cigarette flow and diffusion simulation, and filter tip flow and filtration effect simulation. Particle-type heated cigarettes differ significantly from sheet materials in terms of the porous nature and filling state of the tobacco particles, resulting in more complex internal smoke flow and heat transfer processes. The lack of relevant simulation research has brought a series of problems and drawbacks to the research and development, performance optimization, and quality control of this type of product, specifically: 1. Lack of theoretical support for product design, making it difficult to optimize core performance. Without flow and heat transfer simulations, it is impossible to clearly define the temperature and flow field distribution patterns in the particle packing area, making it difficult to accurately control parameters such as the loose packing density and particle size distribution of the tobacco particles. Different heating methods (such as center heating and circumferential heating) have significant differences in heat transfer efficiency to the granular cigarette core. Without simulations, it is impossible to know the conduction and radiation paths of heat in the particle gaps, nor how airflow drives heat diffusion. 2. Lower research and development efficiency and higher product development costs. Without simulation tools, research and development can only rely on a large number of comparative experiments. For example, investigating the effects of particle parameters and heating parameters on smoke release requires preparing samples of various sizes and conducting repeated tests. However, numerical simulation methods can quickly obtain temperature and flow field data, which significantly reduces the amount of experimentation. The lack of relevant research has prolonged the development cycle of granular heated cigarettes and significantly increased development costs. Summary of the Invention

[0003] This invention addresses the shortcomings of existing technologies by proposing a temperature field analysis method for the heat transfer characteristics of particulate heated cigarette smoke. This method aims to accurately simulate the airflow and temperature field distribution of particulate heated cigarette smoke, thereby improving the precision of product design, ensuring the stability of core performance, enhancing R&D efficiency, and driving technological breakthroughs in the industry.

[0004] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: The temperature field analysis method for the heat transfer characteristics of particulate heated cigarette smoke of the present invention is characterized by the following steps: S1: Based on the actual shape and size of each component of the granular heated cigarette, the granular heated cigarette is divided into different functional sections, including: granular section, barrier section, cooling section, filter section and cavity section, thereby establishing a geometric model of the granular heated cigarette. S2: After meshing the geometric model of the granular heated cigarette, the pressure drop equation and heat transfer equation of different functional sections in the granular heated cigarette are established by using the finite element analysis method. Then, the periodic equation of the suction pressure of the granular heated cigarette and the temperature rise equation of the granular section of the granular heated cigarette are established by using the UDF function. S3: Set the physical properties of the porous medium in granular heated cigarettes, as well as the boundary conditions related to heating temperature and suction pressure; S4: Based on S2-S3, use numerical simulation software to simulate the smoke velocity and smoke pressure of granular heated cigarettes, and verify whether the simulation results output by the smoke flow characteristic simulation model conform to Darcy's law. If they do, use the smoke flow characteristic simulation model of granular heated cigarettes that conforms to Darcy's law to obtain the temperature field and flow field distribution of granular heated cigarettes. Otherwise, return to S3 to reset.

[0005] The temperature field analysis method for the heat transfer characteristics of particulate heated cigarette smoke described in this invention is also characterized in that S2 includes the following steps: S2.1: Construct the pressure drop equation for the particle segment using equation (1): (1) In equation (1), This indicates the pressure change of the particle segment before and after suction; This represents the unit length of a particle within a particle segment; This indicates the density of the porous medium within the particle segment; Indicates the diameter of the particles in the particle segment; This indicates the permeation rate of flue gas in a porous medium in the particulate segment; Porosity represents the porosity of porous media; The curvature of the actual flow path in a porous medium; This indicates the velocity of the flue gas in the particulate section. The flow coefficient is determined by the Reynolds number; S2.2: Construct the heat transfer equation for the particle segment using equation (2): (2) In equation (2), The effective density of the particle segment, The effective specific heat capacity of the particle segment. Temperature of the particle segment Regarding time The partial derivatives; The density of the flue gas within the particulate segment. This refers to the specific heat capacity of the flue gas within the particulate section. This indicates the flow velocity of flue gas within the particle segment; Indicates the flue gas temperature within the particulate section. The gradient; This represents the entropy generation rate of the particle segment due to heat conduction; It is the heat flow vector of the porous medium within the particle segment. It is the heat source term per unit volume of the particle segment, and has: (3) (4) In equation (3), This indicates the porosity of the porous medium in the particle segment; This indicates the density of the solid within the particle segment; is the specific heat capacity of the solid in the particle segment; In equation (4), Let represent the effective thermal conductivity of the porous medium in the particle segment, and we have: (5) In equation (5), This represents the effective thermal conductivity of the flue gas within the particle segment; This indicates the effective thermal conductivity of the particles within the particle segment; S2.3: Construct the heat transfer equation for the fluid inside the barrier section using equation (6): (6) In equation (6), To reduce the density of flue gas within the isolation section, To block the specific heat capacity of the flue gas within the section, Indicates the internal temperature of the barrier section Regarding time The partial derivatives; It is the velocity vector of the fluid inside the barrier section; Temperature within the barrier section gradient, This indicates the temperature change within the barrier section caused by heat conduction; It is the heat flow vector of the fluid inside the barrier section; It is the entropy generation rate of the fluid inside the barrier section caused by heat conduction; It is the heat source term within the barrier section; The effective thermal conductivity of the fluid inside the barrier section; S2.4: Construct the heat transfer equation for the solid outside the barrier section using equation (7): (7) In equation (7), The density of the solid outside the barrier section; The specific heat capacity of the solid outside the barrier section; Indicates the external temperature of the barrier section Regarding time The partial derivatives; It is the entropy generation rate of the solid outside the barrier section caused by heat conduction; It is the heat flow vector of the solid outside the barrier section; This is to block heat sources outside the section; The effective thermal conductivity of the solid outside the barrier section; It is the temperature of the external solid of the barrier section. The gradient; S2.5: Construct the temperature rise equation for the particle segment of granular heated cigarettes using equation (8). : (8) In equation (8), This indicates the wall temperature of granular heated cigarettes; Indicates ambient temperature; This is the temperature rise coefficient; It is the temperature difference index; The suction pressure at the smoke outlet of the granular heated cigarette is constructed using equation (9). Periodic equation: (9) In equation (9), Indicates the suction cycle. , Indicates the aspiration interval. Indicates the suction time. This indicates the suction pressure at the flue gas outlet. Indicates the total number of suction ports. This indicates the number of any given suction port.

[0006] Furthermore, in S4, the smoke velocity along the axial centerline of the granular heated cigarette, which conforms to Darcy's law during the smoking process, is obtained using equation (10). With flue gas pressure The linear relationship between them: (10) In equation (10), Indicates the permeability of porous media; This indicates the dynamic viscosity of the fluid within a porous medium. Indicates the pressure of flue gas along the direction of fluid flow. The gradient.

[0007] Furthermore, considering the swirling and shearing flow of cigarette smoke in S1, the preferred geometric model is SST k- Turbulence model.

[0008] The present invention provides an electronic device, including a memory and a processor, characterized in that the memory is used to store a program supporting the processor in performing the method described therein, and the processor is configured to execute the program stored in the memory.

[0009] The present invention discloses a computer-readable storage medium storing a computer program, characterized in that the computer program is executed by a processor to perform the steps of the method described thereon.

[0010] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention provides a temperature field analysis method for the heat transfer characteristics of granular heated cigarette smoke. Numerical and theoretical models of airflow and heat flow during the cigarette heating process are established. Fluent simulation software is used to simulate the internal flow and heat transfer process of the granular heated cigarette. The actual state of gas flow and cigarette heating process is monitored, and simulation results such as velocity distribution, airflow distribution, and temperature distribution inside the cigarette are obtained during the smoking process. The distribution characteristics of airflow and heat flow during the smoking process of granular heated cigarette are analyzed. The simulation results have important guiding significance for the design and application of granular heated cigarettes.

[0011] 2. This invention constructs a temperature field analysis method for the heat transfer characteristics of particulate heated cigarette smoke flow. With the help of this temperature field analysis method, key data such as micro airflow velocity and temperature gradient in the particle gap can be quickly obtained through numerical simulation, replacing a large number of repetitive physical experiments, improving R&D efficiency, shortening product iteration cycle and reducing R&D costs. Attached Figure Description

[0012] Figure 1 This is a flowchart of the present invention; Figure 2 This is a physical model diagram of an embodiment; Figure 3 This is a diagram illustrating the mesh division in an example. Figure 4 This is a graph showing the change in heating temperature over time. Figure 5 This is a graph showing the change in suction end pressure over time. Figure 6 This is a typical velocity field distribution diagram for an example; Figure 7 This is a typical flow field distribution diagram for an example; Figure 8 This is a typical temperature field distribution diagram for an example. Detailed Implementation

[0013] In this embodiment, considering the significant reduction in the release of harmful smoke components during cigarette combustion, the main development direction for heated cigarettes will be the satisfaction of the smoke's taste and physiological intensity. Cigarette combustion is a multi-factor coupled and highly transient process, with factors such as flow and oxidation reaction rates interacting with each other. Research on the flow and heat transfer of granular electrically heated cigarettes will provide data support and a theoretical foundation for the development of granular heated cigarettes, while also providing the industry with a shared platform for the design and optimization of heated products. This will help further improve and refine the R&D capabilities in the field of granular heated cigarettes and enhance the core competitiveness of granular heated cigarette products. Therefore, a temperature field analysis method for the flow and heat transfer characteristics of granular heated cigarette smoke is proposed, which involves constructing a... Figure 2 The physical model of the granular electrically heated cigarette and the numerical model of the airflow and heat flow during the heating process are shown. SST k- Turbulence and two-phase local thermal equilibrium models were used to establish pressure drop and heat transfer equations for different functional sections of cigarette smoke. A UDF (Underlying Dynamic Function) was then used to import the suction pressure and dynamic heating conditions of the granular section. After fitting and comparing with Darcy's law, the numerical simulation method for the flow and heat transfer characteristics of granular heated cigarette smoke provided by this invention can accurately simulate the airflow and temperature field distribution of granular electrically heated cigarette smoke. Specifically, as... Figure 1 As shown, the method includes the following steps: S1: Based on the actual shape and size of each component of the granular heated cigarette, the granular heated cigarette is divided into different functional sections, including: a granular section, a barrier section, a cooling section, a filtering section, and a cavity section, thus establishing a geometric model of the granular heated cigarette. In the granular section, tobacco particles react and mix with air to form high-temperature smoke. The barrier section initially filters out the solid phase in the high-temperature smoke, preventing the tobacco core particles from entering the cooling section, providing draw resistance, enhancing the smoking experience, and initially cooling the smoke. The cooling section is a hollow area used to lower the temperature of the smoke, while also rectifying and slowing down the gas passing through the small holes in the barrier section at high speed. The filtering section filters out most of the solid phase in the smoke, ensuring high-purity gas at the outlet, improving the smoking experience, and lowering the smoke temperature to near body temperature. The cavity section further enhances the smoking experience. The granular section and cooling section are connected through the four small holes in the barrier section, and the cooling section, filtering section, and cavity section are connected sequentially. The granule section consists of two cylindrical sections. The first section is 13mm long and 3.6mm in radius, and the second section is 3mm long and 3.3mm in radius, fitting snugly against the barrier component. Tobacco granules are distributed within the granule section. The barrier component is made of polylactic acid (PLA), which does not deform or decompose at 300℃. It is 7mm long and 6.6mm in diameter, gear-shaped with 13-16 gear grooves, each 0.7mm deep and wide. A central circular groove is 3mm deep, and the bottom of the groove has four 0.85mm diameter through holes. The cooling section consists of two cylindrical sections with four small holes. The first cylindrical section is 3mm long and 3.3mm in radius, with four 0.85mm diameter, 1mm deep holes, fitting snugly against the barrier component. The second cylindrical section is 12mm long and 3.6mm in radius. The filter section is a cylinder made of cellulose acetate, with a radius of 3.6mm and a length of 10mm. The cavity section is a cylinder with a radius of 3.6 mm and a length of 3 mm.

[0014] The specific geometric model is shown in Table 1.

[0015] Table 1. Geometric model parameters of granular heated cigarettes:

[0016] S2: The geometric model of the granular heated cigarette was meshed. O-shaped mesh blocks were used for meshing, resulting in six groups of O-shaped meshes on the front view and seven segments on the right view, facilitating later grouping. The final mesh had 511 blocks, totaling 5,322,170 meshes. Mesh quality of 0.95 or higher accounted for 51.338%, quality of 0.9 or higher accounted for 84.857%, and quality of 0.85 or higher accounted for 96.717%. There were no meshes with a quality below 0.65, indicating excellent overall mesh quality.

[0017] The pressure drop equation and heat transfer equation for different functional sections within granular heated cigarettes were established using the finite element method. Then, the periodic equation for the inhalation pressure and the temperature rise equation for the granular section of the granular heated cigarette were established using a UDF function. like Figure 3 As shown, SST k- is selected. The turbulence model considers the flow at the orifice as a jet, with significant swirling in the cooling section, especially at the wall. Furthermore, the flue gas should be considered a compressible fluid. Therefore, k- The model is not applicable; traditional k- The turbulence model incorporates the effects of low Reynolds number, compressibility, and shear flow diffusion, making it suitable for cigarettes, but less effective than the k-flow model in far-field calculations. The model is efficient. The SST k-omega model combines k- The model's advantage in far-field calculations makes it more suitable for the flow of cigarette smoke. Meanwhile, heat transfer in the particle section and filter section falls under the category of gas-solid two-phase porous media heat transfer, as does heat transfer between the barrier components and the air. Since the volumetric heat capacity of air is much smaller than that of porous media, a two-phase local thermal equilibrium model is adopted.

[0018] The granular segment and filter segment of granular heated cigarettes are porous media. Assuming that the porous media is an isotropic, homogeneous, rigid porous media, the airflow is incompressible air, and its density and viscosity are constants that do not change with temperature, and satisfy the porous media flow equation, as shown in the following equation: (11) (12) The interior of the barrier section and the cooling section is filled with air, satisfying the free flow equation as shown below: (13) (14) in, represents density, and u represents the permeation rate of flue gas in the porous medium; Indicates the rate of flue gas formation. Indicates viscosity, k Indicates the permeability of porous media. It represents the porosity of porous media.

[0019] S2.1: The particle segment is imagined as a tube-ball model. The resistance formed by the fluid flowing through the unit tube-ball model can be regarded as the sum of the pipe flow resistance, the flow resistance around the ball, and the variable diameter resistance formed by the change of the gap between the ball and the pipe wall. The pressure drop equation of the particle segment is constructed using equation (1): (1) In equation (1), This indicates the pressure change of the particle segment before and after suction; This represents the unit length of a particle within a particle segment; The pressure gradient in the particle segment is described due to fluid viscosity and porosity. This represents the pressure gradient in the particle segment caused by the inertial effect and porosity during fluid flow. This indicates the density of the porous medium within the particle segment; Indicates the diameter of the particles in the particle segment; This indicates the permeation rate of flue gas in a porous medium in the particulate segment; Porosity represents the porosity of porous media; The curvature of the actual flow path in a porous medium; This indicates the velocity of the flue gas in the particulate section. The flow coefficient is determined by the Reynolds number.

[0020] S2.2: Construct the heat transfer equation for the particle segment using equation (2): (2) In equation (2), The effective density of the particle segment, The effective specific heat capacity of the particle segment. Temperature of the particle segment Regarding time The partial derivatives; The density of the flue gas within the particulate segment. This refers to the specific heat capacity of the flue gas within the particulate section. This indicates the flow velocity of flue gas within the particle segment; Indicates the flue gas temperature within the particulate section. The gradient; This represents the entropy generation rate of the particle segment due to heat conduction; It is the heat flow vector of the porous medium within the particle segment. It is the heat source term per unit volume of the particle segment, and has: (3) (4) In equation (3), This indicates the porosity of the porous medium in the particle segment; This indicates the density of the solid within the particle segment; This represents the specific heat capacity of the solid in the particle segment.

[0021] In equation (4), Let represent the effective thermal conductivity of the porous medium in the particle segment, and we have: (5) In equation (5), This represents the effective thermal conductivity of the flue gas within the particle segment; This represents the effective thermal conductivity of the particles within the particle segment.

[0022] S2.3: Construct the heat transfer equation for the fluid inside the barrier section using equation (6): (6) In equation (6), To reduce the density of flue gas within the isolation section, To block the specific heat capacity of the flue gas within the section, Indicates the internal temperature of the barrier section Regarding time The partial derivatives; It is the velocity vector of the fluid inside the barrier section; Temperature within the barrier section gradient, This indicates the temperature change within the barrier section caused by heat conduction; It is the heat flow vector of the fluid inside the barrier section; It is the entropy generation rate of the fluid inside the barrier section caused by heat conduction; It is the heat source term within the barrier section; It is the effective thermal conductivity of the fluid inside the barrier section.

[0023] S2.4: Construct the heat transfer equation for the solid outside the barrier section using equation (7): (7) In equation (7), The density of the solid outside the barrier section; The specific heat capacity of the solid outside the barrier section; Indicates the external temperature of the barrier section Regarding time The partial derivatives; It is the entropy generation rate of the solid outside the barrier section caused by heat conduction; It is the heat flow vector of the solid outside the barrier section; This is to block heat sources outside the section; The effective thermal conductivity of the solid outside the barrier section; It is the temperature of the external solid of the barrier section. The gradient.

[0024] S2.5: Construct the temperature rise equation for the particle segment of granular heated cigarettes using equation (8). The specific function form is a quadratic function from 0s to 25s, heating from 300K to 563K, and from 25s to 110s the temperature stabilizes at 563K. Figure 4As shown. Simultaneously, equation (9) is used to construct a periodic equation for the suction pressure at the flue gas outlet. Specifically, the function is a 2-second suction cycle every 28 seconds, with the suction phase function being a quadratic function, the peak being a negative pressure of 1500 Pa. Figure 5 As shown.

[0025] (8) In equation (8), This indicates the wall temperature of granular heated cigarettes; Indicates ambient temperature; This is the temperature rise coefficient; The temperature difference index is set to 0.25.

[0026] The suction pressure at the smoke outlet of the granular heated cigarette is constructed using equation (9). Periodic equation: (9) In equation (9), Indicates the suction cycle. , Indicates the aspiration interval. Indicates the suction time. This indicates the suction pressure at the flue gas outlet. Indicates the total number of suction ports. This indicates the number of any given suction port.

[0027] In S2, the particle section and filter section are porous media, satisfying the porous media flow equation. The barrier section and cooling section contain air, satisfying the free region flow equation. The particle section is hypothetically modeled as a tube-ball model. The resistance formed by the fluid flowing through the unit tube-ball model can be regarded as the sum of the pipe flow resistance, the flow resistance around the small ball, and the variable diameter resistance formed by the change in the gap between the ball and the pipe wall. Thus, the pressure drop formula of the particle section is obtained and the pressure drop of the particle section is input through UDF. At the same time, the heat transfer equation of each functional section is defined, assuming that the thermal properties of each functional section of the cigarette and the air do not change with temperature, i.e., they are fixed constants, and the heat absorption of the volatilization of residual moisture and other substances is ignored. The heat transfer inside the barrier section is fluid heat transfer, and the heat transfer outside the barrier section is solid heat transfer. The temperature rise equation of the cigarette particle section is written using UDF. The specific function form is a quadratic function from 0s to 25s, heating from 300K to 563K, and the temperature stabilizes at 563K from 25s to 110s. At the same time, a periodic equation for the suction pressure at the flue gas outlet was written. The specific function form is that a suction is performed every 28 seconds for a period of 2 seconds. The suction phase function is a quadratic function with a peak of negative pressure of 1500 Pa.

[0028] S3: Set the physical properties of the porous medium for granular heated cigarettes, as well as the boundary conditions related to heating temperature and suction pressure. In this implementation, the simple algorithm is used, the discretization method is a second-order upwind scheme, a pressure-based solver is used, and the number of iterations is set to 1000. The inlet pressure of the flue gas is atmospheric pressure, and the pressure difference required to reach the outlet flow rate is constant, thus obtaining the outlet pressure. This pressure is used as the outlet pressure during the suction stage. A UDF is used to program the pressure transformation. Except for the barrier component wall material being set to plastic, the outer wall material of all other sections is set to cigarette paper. Except for the wall temperature of the barrier component along the pipe direction being set to a coupled form, the temperature of the rest is set to constant temperature. The heating temperature of the outer periphery of the cigarette core particles is also programmed using a UDF. The flue gas outlet, barrier component, wall temperature of each section, and ambient temperature are all set to 300K. The wall thickness is 25μm, and natural convection with the external environment is used, with a wall boundary condition. The natural convection heat transfer coefficient is 10W / (m²). 2 ·K -1 The wall surface showed no slippage. The heating power of each section was 0. The region was divided into a flow domain and a solid domain. In the flow domain, the granular and filter sections were set as porous media with porosities of 0.5 and 0.72, respectively. The porous materials were all used in the filter sections. The remaining sections were conventional flow domains, with flue gas as the fluid. The solid domain mainly consisted of barrier components made of polylactic acid. Five materials were used in the model: flue gas, polylactic acid, filter section, granular section, and cigarette paper. Specific parameters are shown in Table 2.

[0029] Table 2 Physical property parameters of the granular heated cigarette model

[0030] S4: Based on S2-S3 and the input inlet and outlet pressure values ​​and wall temperature, the smoke velocity and smoke pressure of granular heated cigarettes are simulated using numerical simulation software (Fluent software). The actual operating status of the cigarette smoking process is monitored, the simulation results are recorded, and the velocity, streamline and temperature distribution results of each functional section are obtained.

[0031] The simulation results of the flue gas flow characteristics simulation model are verified to conform to Darcy's law. If the flue gas velocity and flue gas pressure values ​​along the axial centerline of the cigarette show a significant linear correlation after fitting verification, the verification is considered successful. The temperature field and flow field distribution of the granular heated cigarette are then obtained using the flue gas flow characteristics simulation model conforming to Darcy's law, yielding velocity, streamline, and temperature distribution contour maps for each functional section. Typical results are shown below. Figure 6 , Figure 7 , Figure 8 As shown; if the flue gas velocity and pressure values ​​on the axial centerline of the cigarette stick do not show a significant linear correlation after fitting verification, return to S3 to reset.

[0032] In practice, equation (10) is used to obtain the smoke velocity along the axial centerline of the granular heated cigarette that conforms to Darcy's law during the smoking process. With flue gas pressure The linear relationship between them: (10) In equation (10), Indicates the permeability of porous media; This indicates the dynamic viscosity of the fluid within a porous medium. Indicates the pressure of flue gas along the direction of fluid flow. The gradient.

[0033] In this embodiment, an electronic device includes a memory and a processor. The memory stores a program that supports the processor in executing the above-described method, and the processor is configured to execute the program stored in the memory.

[0034] In this embodiment, a computer-readable storage medium stores a computer program, which is executed by a processor to perform the steps of the above method.

[0035] In summary, this invention provides a numerical simulation method for the flow and heat transfer characteristics of granular heated cigarette smoke. It establishes flow and heat transfer models for heated cigarettes, enabling the study of the influence of smoking and heating conditions on the flow characteristics of heated cigarette smoke. This provides a theoretical basis and data support for the optimized design of granular heated cigarettes, contributing to the further improvement and refinement of R&D capabilities in the field and enhancing the core competitiveness of granular heated cigarette products.

Claims

1. A method for analyzing the temperature field of heat transfer characteristics of particulate heated cigarette smoke, characterized in that, Includes the following steps: S1: Based on the actual shape and size of each component of the granular heated cigarette, the granular heated cigarette is divided into different functional sections, including: granular section, barrier section, cooling section, filter section and cavity section, thereby establishing a geometric model of the granular heated cigarette. S2: After meshing the geometric model of the granular heated cigarette, the pressure drop equation and heat transfer equation of different functional sections in the granular heated cigarette are established by using the finite element analysis method. Then, the periodic equation of the suction pressure of the granular heated cigarette and the temperature rise equation of the granular section of the granular heated cigarette are established by using the UDF function. S3: Set the physical properties of the porous medium in granular heated cigarettes, as well as the boundary conditions related to heating temperature and suction pressure; S4: Based on S2-S3, use numerical simulation software to simulate the smoke velocity and smoke pressure of granular heated cigarettes, and verify whether the simulation results output by the smoke flow characteristic simulation model conform to Darcy's law. If they do, use the smoke flow characteristic simulation model of granular heated cigarettes that conforms to Darcy's law to obtain the temperature field and flow field distribution of granular heated cigarettes. Otherwise, return to S3 to reset.

2. The temperature field analysis method for the heat transfer characteristics of particulate heated cigarette smoke according to claim 1, characterized in that, S2 includes the following steps: S2.1: Construct the pressure drop equation for the particle segment using equation (1): (1) In equation (1), This indicates the pressure change of the particle segment before and after suction; This represents the unit length of a particle within a particle segment; This indicates the density of the porous medium within the particle segment; Indicates the diameter of the particles in the particle segment; This indicates the permeation rate of flue gas in a porous medium in the particulate segment; Porosity represents the porosity of porous media; The curvature of the actual flow path in a porous medium; This indicates the velocity of the flue gas in the particulate section. The flow coefficient is determined by the Reynolds number; S2.2: Construct the heat transfer equation for the particle segment using equation (2): (2) In equation (2), The effective density of the particle segment, The effective specific heat capacity of the particle segment. Temperature of the particle segment Regarding time The partial derivatives; The density of the flue gas within the particulate segment. This refers to the specific heat capacity of the flue gas within the particulate section. This indicates the flow velocity of flue gas within the particle segment; Indicates the flue gas temperature within the particulate section. The gradient; This represents the entropy generation rate of the particle segment due to heat conduction; It is the heat flow vector of the porous medium within the particle segment. It is the heat source term per unit volume of the particle segment, and has: (3) (4) In equation (3), This indicates the porosity of the porous medium in the particle segment; This indicates the density of the solid within the particle segment; is the specific heat capacity of the solid in the particle segment; In equation (4), Let represent the effective thermal conductivity of the porous medium in the particle segment, and we have: (5) In equation (5), This represents the effective thermal conductivity of the flue gas within the particle segment; This indicates the effective thermal conductivity of the particles within the particle segment; S2.3: Construct the heat transfer equation for the fluid inside the barrier section using equation (6): (6) In equation (6), To reduce the density of flue gas within the isolation section, To block the specific heat capacity of the flue gas within the section, Indicates the internal temperature of the barrier section Regarding time The partial derivatives; It is the velocity vector of the fluid inside the barrier section; Temperature within the barrier section gradient, This indicates the temperature change within the barrier section caused by heat conduction; It is the heat flow vector of the fluid inside the barrier section; It is the entropy generation rate of the fluid inside the barrier section caused by heat conduction; It is the heat source term within the barrier section; The effective thermal conductivity of the fluid inside the barrier section; S2.4: Construct the heat transfer equation for the solid outside the barrier section using equation (7): (7) In equation (7), The density of the solid outside the barrier section; The specific heat capacity of the solid outside the barrier section; Indicates the external temperature of the barrier section Regarding time The partial derivatives; It is the entropy generation rate of the solid outside the barrier section caused by heat conduction; It is the heat flow vector of the solid outside the barrier section; This is to block heat sources outside the section; The effective thermal conductivity of the solid outside the barrier section; It is the temperature of the external solid of the barrier section. The gradient; S2.5: Construct the temperature rise equation for the particle segment of granular heated cigarettes using equation (8). : (8) In equation (8), This indicates the wall temperature of granular heated cigarettes; Indicates ambient temperature; This is the temperature rise coefficient; It is the temperature difference index; The suction pressure at the smoke outlet of the granular heated cigarette is constructed using equation (9). Periodic equation: (9) In equation (9), Indicates the suction cycle. , Indicates the aspiration interval. Indicates the suction time. This indicates the suction pressure at the flue gas outlet. Indicates the total number of suction ports. This indicates the number of any given suction port.

3. The temperature field analysis method for the heat transfer characteristics of particulate heated cigarette smoke according to claim 2, characterized in that, In S4, the smoke velocity along the axial centerline of the granular heated cigarette, which conforms to Darcy's law during the smoking process, is obtained using equation (10). With flue gas pressure The linear relationship between them: (10) In equation (10), Indicates the permeability of porous media; This indicates the dynamic viscosity of the fluid within a porous medium. Indicates the pressure of flue gas along the direction of fluid flow. The gradient.

4. The temperature field analysis method for the heat transfer characteristics of particulate heated cigarette smoke according to claim 1, characterized in that, In S1, considering the swirling and shearing flow of cigarette smoke, the preferred geometric model is SST k-. Turbulence model.

5. An electronic device, comprising a memory and a processor, characterized in that, The memory is used to store a program that supports a processor in executing the method of any one of claims 1-4, the processor being configured to execute the program stored in the memory.

6. A computer-readable storage medium storing a computer program thereon, characterized in that, The computer program is executed by the processor to perform the steps of the method according to any one of claims 1-4.

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