A method and system for heat transfer analysis of a heat-not-burn cigarette during puff-by-puff smoking

Abstract

This invention discloses a method and system for heat transfer analysis during puff-by-puff inhalation of heated non-combustible cigarettes, relating to the field of tobacco processing technology. The method includes: a preheating stage, where a cigarette heat conduction equation is constructed based on equivalent thermal conductivity, equivalent density, and equivalent volumetric heat capacity to obtain the internal temperature of the cigarette during the preheating stage, varying with time and the radial and axial positions of the cigarette; a puff-by-puff inhalation stage, where an unsteady-state pressure diffusion equation is constructed by introducing porosity to obtain the inhalation pressure field varying with time and axial position, and a steady-state Darcy equation is constructed based on the inhalation pressure field to obtain the axial airflow velocity field of the tobacco shreds varying with time and axial position; updating the porosity and equivalent thermal conductivity, using the internal temperature of the cigarette as the initial temperature for the puff-by-puff stage, and combining it with the axial airflow velocity of the tobacco shreds, a heat conduction-convection equation is constructed to obtain the cigarette temperature field varying with time, radial, and axial positions during the puff-by-puff process. This achieves accurate analysis of the flow heat transfer performance of heated non-combustible cigarettes.

Description

Technical Field

[0001] This invention relates to the field of tobacco processing technology, and in particular to a method and system for analyzing heat transfer during puffing of heated non-combustible cigarettes. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] The heat transfer characteristics of heated tobacco products are a key factor affecting the release of chemical components in the smoke and the user experience. As the core area for smoke generation, the heat transfer process of the core section plays a decisive role in the performance of heated tobacco products.

[0004] Currently, although a large number of studies have been conducted on heat and mass transfer in heated tobacco products, involving aspects such as filter temperature, smoke release patterns, and smoking modes, and numerical methods have been used to explore the overall heat transfer performance, a systematic and precise analysis of the detailed heat transfer mechanism of the core section during the heating process is still lacking.

[0005] Heat transfer in heated tobacco products involves two key stages: preheating and heated inhalation. Existing research lacks in-depth and comprehensive numerical calculations and analyses of the internal temperature field distribution within the core segment during the preheating stage, as well as the coordinated changes in velocity, temperature, and pressure fields under the coupling effect of the heat conduction control equation and flow equation during the heated inhalation stage. This results in a lack of precise theoretical basis and a degree of uncertainty in optimizing the core structure to enhance heat transfer's ability to regulate smoke release and in promoting the development of new heated tobacco products.

[0006] Therefore, conducting heat transfer calculation studies centered on the core section of the cigarette and clarifying the temperature, velocity, and pressure distribution characteristics at different stages is of great significance for the optimized design of heated cigarettes. Summary of the Invention

[0007] To address the aforementioned issues, this invention proposes a method and system for heat transfer analysis during puff-by-puff inhalation of heated tobacco products. The method divides the heat transfer calculation of heated tobacco into a preheating stage and a puff-by-puff stage, enabling precise analysis of the flow heat transfer performance of heated tobacco products. This provides technical guidance for the optimized design of heated tobacco products and the development of new types of cigarettes.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a method for heat transfer analysis during puffing of a heated non-combustible cigarette, comprising: During the preheating stage, the equivalent thermal diffusivity is calculated based on the equivalent thermal conductivity, equivalent density, and equivalent volumetric heat capacity after the air and tobacco are mixed. The thermal conductivity equation of the cigarette is then constructed based on the equivalent thermal diffusivity to obtain the internal temperature of the cigarette during the preheating stage, which varies with time, the radial position of the cigarette, and the axial position of the cigarette. During the puff-by-puff stage, an unsteady pressure diffusion equation is constructed by introducing porosity. At the current moment, the porosity is updated according to the position of the cigarette after puffing. Based on the unsteady pressure diffusion equation, the puffing pressure field that varies with time and the axial position of the cigarette is obtained. Based on the puffing pressure field, a steady-state Darcy equation is constructed, and the axial airflow velocity field of the tobacco that varies with time and the axial position of the cigarette is obtained by solving it. The equivalent thermal conductivity is updated based on the updated porosity. The internal temperature of the cigarette is obtained by using the cigarette heat conduction equation. The internal temperature of the cigarette is used as the initial temperature of the puff-by-puff stage. Combined with the axial airflow velocity of the tobacco, a heat conduction-convection equation is constructed. The temperature field of the cigarette that varies with time, radial position and axial position of the cigarette during the puff-by-puff process is obtained by solving this equation.

[0009] As an alternative implementation, the thermal conductivity equation of the cigarette is: ; in, For temperature; For time; The coordinates are the directional coordinates of the tobacco shred radius; The coordinates are along the length of the cigarette. denoted as thermal diffusivity.

[0010] As an alternative implementation, the thermal diffusivity in the cigarette thermal conductivity equation is adopted as the equivalent thermal diffusivity. : ; ; ; ; in, Equivalent thermal conductivity; The thermal conductivity of air; The thermal conductivity of tobacco shreds; Porosity; Equivalent density; air density; The density of the tobacco shreds; Equivalent volumetric heat capacity; This refers to the heat capacity per unit volume of air. This represents the heat capacity per unit volume of tobacco.

[0011] As an alternative implementation, the unsteady pressure diffusion equation is: ; in, For time; This refers to the suction pressure; The permeability of the porous medium of tobacco shreds; The dynamic viscosity of the flue gas; Porosity; The coordinates are along the length of the cigarette.

[0012] As an alternative implementation method, the axial airflow velocity of the tobacco for: .

[0013] As an alternative implementation, the heat conduction-convection equation is: ; in, For temperature; For time; The coordinates are the directional coordinates of the tobacco shred radius; The coordinates are along the length of the cigarette. The axial airflow velocity of the tobacco shreds.

[0014] Secondly, the present invention provides a heat transfer analysis system for puffing heated non-combustible cigarettes, comprising: The preheating stage analysis module is configured to calculate the equivalent thermal diffusivity based on the equivalent thermal conductivity, equivalent density, and equivalent volumetric heat capacity after considering the mixing of air and tobacco during the preheating stage. Based on the equivalent thermal diffusivity, a cigarette thermal conductivity equation is constructed to solve for the internal temperature of the cigarette during the preheating stage, which varies with time, the radial position of the cigarette, and the axial position of the cigarette. The pressure-velocity field analysis module during the puffing stage is configured to construct an unsteady pressure diffusion equation by introducing porosity during the puffing stage. At the current moment, the porosity is updated according to the position of the cigarette after puffing. Based on the unsteady pressure diffusion equation, the puffing pressure field that varies with time and the axial position of the cigarette is obtained. Based on the puffing pressure field, a steady-state Darcy equation is constructed to solve for the axial airflow velocity field of the tobacco that varies with time and the axial position of the cigarette. The temperature field analysis module during the smoking stage is configured to update the equivalent thermal conductivity based on the updated porosity. The internal temperature of the cigarette is then obtained using the cigarette heat conduction equation. The internal temperature of the cigarette is used as the initial temperature for each puff. Combined with the axial airflow velocity of the tobacco, a heat conduction-convection equation is constructed. This equation is then used to solve for the temperature field of the cigarette that varies with time, the radial position of the cigarette, and the axial position of the cigarette during each puff.

[0015] Thirdly, the present invention provides an electronic device including a memory and a processor, and computer instructions stored in the memory and running on the processor, wherein the computer instructions, when executed by the processor, perform the method described in the first aspect.

[0016] Fourthly, the present invention provides a computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the method described in the first aspect.

[0017] Fifthly, the present invention provides a computer program product, including a computer program that, when executed by a processor, implements the method described in the first aspect.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention proposes a method and system for analyzing the heat transfer of heated tobacco products during puff-by-puff inhalation based on the dynamic changes in porosity and thermal conductivity. The heat transfer calculation of heated tobacco products is divided into a preheating stage and a puff-by-puff stage. By establishing a two-dimensional unsteady-state thermal conductivity model in cylindrical coordinates and a fluid-thermal coupling model, accurate analysis of the flow and heat transfer performance of heated tobacco products is achieved. In the preheating stage, the internal temperature field of the tobacco product, varying with time, radial position, and axial position, is obtained by combining the thermal conductivity equation. In the puff-by-puff stage, porosity varying with time and space is introduced, and the velocity and pressure fields are solved using the Darcy equation, combined with the puff-by-puff flow rate. The dynamic temperature field is then solved using the heat conduction-convection equation (with equivalent thermal conductivity dynamically updated with porosity). This analysis of the flow and heat transfer performance of heated tobacco products during inhalation provides technical guidance for the optimized design and development of new types of heated tobacco products.

[0019] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0021] Figure 1 The overall flowchart of the heat transfer analysis method for puffing heated non-combustible cigarettes provided in Embodiment 1 of the present invention is shown below. Figure 2 This is a flowchart of heat transfer analysis during the preheating stage provided in Embodiment 1 of the present invention; Figure 3This is a flow chart of heat transfer analysis for fluid-structure interaction during the suction stage provided in Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of a suction unit function provided in Embodiment 1 of the present invention. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0023] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0024] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form as well. Furthermore, it should be understood that the terms “comprising” and “including”, and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0025] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0026] Example 1 This embodiment provides a method for heat transfer analysis during the puffing of heated non-combustible cigarettes, such as... Figure 1 As shown, it specifically includes: During the preheating stage, the equivalent thermal diffusivity is calculated based on the equivalent thermal conductivity, equivalent density, and equivalent volumetric heat capacity after the air and tobacco are mixed. The thermal conductivity equation of the cigarette is then constructed based on the equivalent thermal diffusivity to obtain the internal temperature of the cigarette during the preheating stage, which varies with time, the radial position of the cigarette, and the axial position of the cigarette. During the puff-by-puff stage, an unsteady pressure diffusion equation is constructed by introducing porosity. At the current moment, the porosity is updated according to the position of the cigarette after puffing. Based on the unsteady pressure diffusion equation, the puffing pressure field that varies with time and the axial position of the cigarette is obtained. Based on the puffing pressure field, a steady-state Darcy equation is constructed, and the axial airflow velocity field of the tobacco that varies with time and the axial position of the cigarette is obtained by solving it. The equivalent thermal conductivity is updated based on the updated porosity. The internal temperature of the cigarette is obtained by using the cigarette heat conduction equation. The internal temperature of the cigarette is used as the initial temperature of the puff-by-puff stage. Combined with the axial airflow velocity of the tobacco, a heat conduction-convection equation is constructed. The temperature field of the cigarette that varies with time, radial position and axial position of the cigarette during the puff-by-puff process is obtained by solving this equation.

[0027] This embodiment divides the heat transfer analysis of heated tobacco products during puff-by-puff inhalation into a preheating stage and a puff-by-puff stage. In the preheating stage, the temperature at different times and locations is analyzed using the tobacco's thermal conductivity equation to clarify the internal temperature field of the tobacco. In the puff-by-puff stage, by introducing porosity that varies with time and space, and combining it with the puff-by-puff flow rate, the distribution of velocity, temperature, and pressure fields during the heated tobacco product inhalation process is analyzed. Therefore, by analyzing the temperature field of the heated tobacco product during the preheating stage and the heat transfer flow characteristics of the smoke during the heated tobacco product inhalation process, guidance is provided for the optimized design and development of new heated tobacco products.

[0028] The method of this embodiment will be described in detail below.

[0029] Step 1: As Figure 2 As shown, during the preheating stage, a column-heated non-combustible cigarette model is constructed to determine the cigarette size and related material parameters. The equivalent thermal diffusivity is calculated based on the equivalent thermal conductivity, equivalent density, and equivalent volumetric heat capacity after considering the mixture of air and tobacco. A two-dimensional unsteady thermal conductivity equation for tobacco is then constructed based on the equivalent thermal diffusivity. Set the initial ambient temperature to The wall temperature is Determine the initial conditions and boundary conditions of the cigarette wall, and calculate the internal temperature of the cigarette based on the cigarette heat conduction equation. .

[0030] Specifically: The temperature distribution inside the cigarette is derived using the heat conduction equation shown in equation (1). Based on the initial conditions and boundary conditions of the cigarette wall shown in equation (2), the temperature in equation (1) is solved using the finite difference method. : (1); in, Temperature in K; Preheating time (in seconds); The coordinates of the tobacco shred radius in mm; The coordinates along the length of the cigarette are in mm. Thermal diffusivity / mm 2 / s.

[0031] Initial conditions and cigarette wall boundary conditions: ; (2); in, The length of the cigarette is in mm; r max and r min These represent the maximum and minimum values ​​in the direction of the tobacco shred radius, respectively.

[0032] thermal diffusivity for: (3); in, Thermal conductivity / W·m -1 ·K -1 ; Density / kg·m -3 ; Specific heat capacity at constant pressure / J·kg -1 ·K -1 .

[0033] Because it involves mixing porous media (air and tobacco), the equivalent thermal diffusivity is used. : (4); in, Equivalent thermal conductivity / W·m -1 ·K -1 ; Equivalent density / kg·m -3 ; Equivalent isobaric specific heat capacity / J·kg -1 ·K -1 ; Equivalent volumetric heat capacity / J·m -3 ·k -1 .

[0034] The equivalent thermal conductivity, equivalent density, and equivalent volumetric heat capacity are as follows: (5); (6); (7); in, Equivalent thermal conductivity / W·m -1 ·K -1 ; air thermal conductivity / W·m -1 ·K -1 ; Thermal conductivity of tobacco shreds / W·m -1 ·K -1 ; Porosity is a dimensionless quantity. Equivalent density / kg·m -3 ; air density / kg·m -3 ; The density of tobacco shreds / kg·m -3 ; Equivalent volumetric heat capacity / J·m -3 ·k -1 ; Heat capacity per unit volume of air / J·m -3 ·k -1 ; Heat capacity per unit volume of tobacco shreds / J·m -3 ·k -1 .

[0035] Step 2: As Figure 3 As shown, in the heating and smoking stage, the continuity equation (8) for heated non-combustible cigarettes and the axial momentum equations (9)-(10) are first constructed: (8); (9); (10); in, Radial airflow velocity of tobacco shreds / m·s -1 ; The axial airflow velocity of the tobacco shreds is given in m·s. -1 ; Flue gas density / kg·m -3 ; Permeability of porous media for tobacco shreds / mm -2 ; The dynamic viscosity of flue gas is expressed in Pa·s. The suction pressure is expressed in Pa.

[0036] In this embodiment, the focus is primarily on the axial motion of the flue gas; therefore, the radial gas flow of the tobacco shreds (i.e.,...) is ignored. When), the axial momentum equations of equations (9)-(10) are simplified to equation (11): (11).

[0037] Step 3: Based on equations (8) and (11) from Step 2, construct the unsteady pressure diffusion equation (12) by introducing porosity: (12).

[0038] The permeation diffusion coefficient D is defined by equation (13); (13); in, Permeability diffusion coefficient / mm 2 ·s -1 ; Porosity is a dimensionless quantity.

[0039] Substituting equation (13) into equation (12) yields the simplified unsteady-state pressure diffusion equation shown in equation (14). Combining this with the boundary conditions shown in equation (15), the suction pressure field varying with time and the axial position of the cigarette is calculated using finite difference. .

[0040] (14); (15); in, Flue gas outlet velocity / m·s -1 .

[0041] Among them, flue gas outlet velocity The calculation process is as follows: Given that the total suction capacity at the outlet in 2 seconds is The flue gas outlet velocity meets the requirements. The equation, and the expression for time, is given by equation (18). Image as Figure 4 As shown.

[0042] (16); (17); pass calculate ; (18); Where A is a coefficient.

[0043] Finally, the suction pressure obtained is used to... Combining the steady-state Darcy equation shown in equation (19), we obtain the axial airflow velocity field of the tobacco as it varies with time and the axial position of the tobacco. ; (19); in, Permeability of porous media for tobacco shreds / mm -2 ; The value is the dynamic viscosity of the flue gas in Pa·s.

[0044] Step 4: The internal temperature of the cigarette obtained during the preheating stage As the initial temperature for the puff-by-puff stage, combined with the axial airflow velocity of the tobacco obtained in step 3. The heat conduction-convection equation of the heated non-combustible cigarette shown in equation (20) is constructed. Combined with the initial conditions of the cigarette shown in equation (21) and the boundary conditions shown in equation (22), the cigarette temperature changes with time, radial position and axial position of the cigarette during the puffing process is obtained by finite difference solution.

[0045] (20); (twenty one); (twenty two).

[0046] During the puffing stage of heated non-combustible cigarettes, the equivalent thermal conductivity of the tobacco shreds is dynamically changing due to temperature and water vapor content variations during the heating process, which in turn dynamically updates the porosity and equivalent thermal conductivity.

[0047] Specifically: at each time step and spatial location, the porosity at the corresponding location is experimentally determined, thereby updating the porosity. Update the equivalent thermal conductivity based on the updated porosity. ; For time radial position and axial position Dynamically changing thermal conductivity For time radial position and axial position Dynamically changing porosity.

[0048] Until the convergence condition check number (CFL number) is met: This enables precise analysis of the flow and heat transfer performance of heated tobacco products, providing guidance for the optimized design and development of new types of heated tobacco products.

[0049] Example 2 This embodiment provides a heat transfer analysis system for puffing heated non-combustible cigarettes, including: The preheating stage analysis module is configured to calculate the equivalent thermal diffusivity based on the equivalent thermal conductivity, equivalent density, and equivalent volumetric heat capacity after considering the mixing of air and tobacco during the preheating stage. Based on the equivalent thermal diffusivity, a cigarette thermal conductivity equation is constructed to solve for the internal temperature of the cigarette during the preheating stage, which varies with time, the radial position of the cigarette, and the axial position of the cigarette. The pressure-velocity field analysis module during the puffing stage is configured to construct an unsteady pressure diffusion equation by introducing porosity during the puffing stage. At the current moment, the porosity is updated according to the position of the cigarette after puffing. Based on the unsteady pressure diffusion equation, the puffing pressure field that varies with time and the axial position of the cigarette is obtained. Based on the puffing pressure field, a steady-state Darcy equation is constructed to solve for the axial airflow velocity field of the tobacco that varies with time and the axial position of the cigarette. The temperature field analysis module during the smoking stage is configured to update the equivalent thermal conductivity based on the updated porosity. The internal temperature of the cigarette is then obtained using the cigarette heat conduction equation. The internal temperature of the cigarette is used as the initial temperature for each puff. Combined with the axial airflow velocity of the tobacco, a heat conduction-convection equation is constructed. This equation is then used to solve for the temperature field of the cigarette that varies with time, the radial position of the cigarette, and the axial position of the cigarette during each puff.

[0050] It should be noted that the above modules correspond to the steps described in Embodiment 1, and the examples and application scenarios implemented by the above modules and the corresponding steps are the same, but are not limited to the content disclosed in Embodiment 1. It should also be noted that the above modules, as part of the system, can be executed in a computer system such as a set of computer-executable instructions.

[0051] In further embodiments, the following is also provided: An electronic device includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, wherein the computer instructions, when executed by the processor, perform the method described in Embodiment 1. For brevity, further details are omitted here.

[0052] It should be understood that in this embodiment, the processor can be a central processing unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor, etc.

[0053] Memory may include read-only memory and random access memory, and provides instructions and data to the processor. A portion of memory may also include non-volatile random access memory. For example, memory may also store information about the device type.

[0054] A computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the method described in Embodiment 1.

[0055] The method in Example 1 can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor. The software modules can reside in readily available storage media in the field, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory, and the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method. To avoid repetition, a detailed description is not provided here.

[0056] A computer program product includes a computer program that, when executed by a processor, implements the method described in Embodiment 1.

[0057] The present invention also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as instructions included in program modules, which execute in a device on a target real or virtual processor to perform the processes / methods described above. Typically, program modules include routines, programs, libraries, objects, classes, components, data structures, etc., that perform specific tasks or implement specific abstract data types. In various embodiments, the functionality of program modules can be combined or divided among program modules as needed. The machine-executable instructions for the program modules can execute within a local or distributed device. In a distributed device, the program modules can reside in both local and remote storage media.

[0058] The computer program code used to implement the methods of the present invention may be written in one or more programming languages. This computer program code may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the computer or other programmable data processing device, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a computer, partially on a computer, as a stand-alone software package, partially on a computer and partially on a remote computer, or entirely on a remote computer or server.

[0059] In the context of this invention, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, and the like. Examples of signals may include electrical, optical, radio, sound, or other forms of propagation signals, such as carrier waves, infrared signals, etc.

[0060] Those skilled in the art will recognize that the units and algorithm steps described in connection with the various examples of this embodiment can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this invention.

[0061] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method of heat transfer analysis of a heat-not-burn cigarette during puff-by-puff smoking, characterized by, include: During the preheating stage, the equivalent thermal diffusivity is calculated based on the equivalent thermal conductivity, equivalent density, and equivalent volume thermal melting of the air and tobacco. The thermal conductivity equation of the cigarette is then constructed based on the equivalent thermal diffusivity to obtain the internal temperature of the cigarette during the preheating stage, which varies with time, the radial position of the cigarette, and the axial position of the cigarette. During the puff-by-puff stage, an unsteady pressure diffusion equation is constructed by introducing porosity. At the current moment, the porosity is updated according to the position of the cigarette after puffing. Based on the unsteady pressure diffusion equation, the puffing pressure field that varies with time and the axial position of the cigarette is obtained. Based on the puffing pressure field, a steady-state Darcy equation is constructed, and the axial airflow velocity field of the tobacco that varies with time and the axial position of the cigarette is obtained by solving it. The equivalent thermal conductivity is updated based on the updated porosity. The internal temperature of the cigarette is obtained by using the cigarette heat conduction equation. The internal temperature of the cigarette is used as the initial temperature of the puff-by-puff stage. Combined with the axial airflow velocity of the tobacco, a heat conduction-convection equation is constructed. The temperature field of the cigarette that varies with time, radial position and axial position of the cigarette during the puff-by-puff process is obtained by solving this equation.

2. A method of heat transfer analysis of a heat-not-burn cigarette per puff as claimed in claim 1, wherein, The thermal conductivity equation for the cigarette is: ； wherein, T is temperature; t is time; r is a radial coordinate of the tobacco; z is a lengthwise coordinate of the cigarette; a is the thermal diffusivity.

3. The heat transfer analysis method for puff-by-puff inhalation of a heated non-combustible cigarette as described in claim 2, characterized in that, The thermal diffusivity in the heat conduction equation of the cigarette is an equivalent thermal diffusivity : ； ； ； ； wherein, Keff is the effective thermal conductivity; Kair is the air thermal conductivity; Ktob is the tobacco thermal conductivity; Por is the porosity; Peff is the effective density; Pair is the air density; Pto is the tobacco density; Ceff is the effective volumetric heat capacity; Cair is the air volumetric heat capacity; Cto is the tobacco volumetric heat capacity.

4. A method of heat transfer analysis of a heat-not-burn cigarette per puff as claimed in claim 1, wherein, The unsteady pressure diffusion equation is: ； wherein, is time; is the draw pressure; is the tobacco porous medium permeability; is the smoke dynamic viscosity; is the porosity; is the cigarette length direction coordinate.

5. The heat transfer analysis method for puff-by-puff inhalation of a heated non-combustible cigarette as described in claim 4, characterized in that, Tobacco rod axial airflow velocity is: .

6. A method of heat transfer analysis of a heat-not-burn cigarette per puff as claimed in claim 1, wherein, The heat conduction-convection equation is: ； in, For temperature; For time; The coordinates are the directional coordinates of the tobacco shred radius; The coordinates are along the length of the cigarette. The axial airflow velocity of the tobacco shreds.

7. A heat transfer analysis system for puffing through a heated non-combustible cigarette, characterized in that, include: The preheating stage analysis module is configured to calculate the equivalent thermal diffusivity based on the equivalent thermal conductivity, equivalent density, and equivalent volumetric heat capacity after considering the mixing of air and tobacco during the preheating stage. Based on the equivalent thermal diffusivity, a cigarette thermal conductivity equation is constructed to solve for the internal temperature of the cigarette during the preheating stage, which varies with time, the radial position of the cigarette, and the axial position of the cigarette. The pressure-velocity field analysis module during the puffing stage is configured to construct an unsteady pressure diffusion equation by introducing porosity during the puffing stage. At the current moment, the porosity is updated according to the position of the cigarette after puffing. Based on the unsteady pressure diffusion equation, the puffing pressure field that varies with time and the axial position of the cigarette is obtained. Based on the puffing pressure field, a steady-state Darcy equation is constructed to solve for the axial airflow velocity field of the tobacco that varies with time and the axial position of the cigarette. The temperature field analysis module during the smoking stage is configured to update the equivalent thermal conductivity based on the updated porosity. The internal temperature of the cigarette is then obtained using the cigarette heat conduction equation. The internal temperature of the cigarette is used as the initial temperature for each puff. Combined with the axial airflow velocity of the tobacco, a heat conduction-convection equation is constructed. This equation is then used to solve for the temperature field of the cigarette that varies with time, the radial position of the cigarette, and the axial position of the cigarette during each puff.

8. An electronic device, characterized in that, It includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, perform the method according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, Used to store computer instructions, which, when executed by a processor, perform the method described in any one of claims 1-6.

10. A computer program product, characterized in that, Includes a computer program, which, when executed by a processor, implements the method described in any one of claims 1-6.

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