Method and system for constructing human body upper airway model with physiological characteristics and medium

Abstract

The invention provides a method and system for constructing a human body upper airway model with physiological characteristics and a medium, and relates to the technical field of respiratory tract model construction.The method comprises the steps that CT scanning data of a human body upper airway are obtained, and an upper airway simulation model with a cartilage ring structure is constructed; constructing a generalized glottis region motion model according to the change condition of the width of the glottis along with time in the breathing process; constructing a generalized glottis region motion model according to the time-varying condition of the displacements of the trachea in three directions in the breathing process; constructing a respiratory tract heat transfer model according to the heat transfer process in the respiratory tract; constructing a wall surface heat transfer function between the throat and the inner surface of the trachea and a wall surface heat transfer function between the oral cavity and the pharynx; and performing dynamic simulation on the upper airway simulation model based on the multiple motion functions and the wall surface heat transfer functions. According to the model construction method, the respiratory tract deformation condition and the respiratory tract wall surface temperature adjustment condition in the breathing process are considered, and the accurate human body upper airway model can be constructed.

Description

Technical Field

[0001] The present invention relates to the technical field of respiratory tract model construction, and in particular to a construction method, system and medium for a human upper airway model with physiological characteristics. Background Art

[0002] There are complex physiological characteristics in the human respiratory process, such as the periodic expansion-contraction movement of the glottis, the periodic expansion-retraction movement of the trachea with cartilage rings, and the heat transfer of the respiratory wall. The existence of these physiological characteristics will affect the study of airflow movement and particle deposition characteristics in the respiratory tract. Establishing a mathematical model that can describe the physiological characteristics of the upper respiratory tract will greatly facilitate the simulation and analysis of the airflow characteristics inside the respiratory tract during real breathing, and help to further understand the physiological functions of the human respiratory system. Therefore, it is necessary to establish an upper airway model that is close to the physiological characteristics of the real respiratory system.

[0003] Although there are many widely used respiratory tract models in respiratory mechanics CFD research, both segmented models and full airway models tend to reflect the geometric characteristics of the respiratory tract and ignore the inherent physiological characteristics of the human respiratory tract, making it difficult to obtain more accurate simulation results. Summary of the invention

[0004] To solve the above problems, the present invention provides a method for constructing a human upper airway model with physiological characteristics. The method takes into account the deformation of the airway during breathing and the temperature regulation of the airway wall, and can construct a more accurate human upper airway model with physiological characteristics.

[0005] To achieve the above object, the present invention provides the following technical solutions.

[0006] A method for constructing a human upper airway model with physiological characteristics comprises the following steps:

[0007] Acquire CT scan data of the human upper airway; acquire the orientation and radius of the cartilage ring of the upper airway and the distance between adjacent cartilage rings according to the CT scan data, and construct an upper airway simulation model with a cartilage ring structure based on a real human upper airway model;

[0008] According to the change of glottal width over time during breathing, a generalized glottal regional motion model is constructed;

[0009] According to the time-varying displacement of the trachea in three directions during breathing, a generalized tracheal regional motion model is constructed.

[0010] According to the heat transfer process in the respiratory tract, the wall heat transfer function between the larynx and the inner surface of the trachea, the wall heat transfer function between the oral cavity and the pharynx, and the wall heat transfer function at the inlet and outlet are constructed;

[0011] Based on the generalized glottis area motion model, the generalized trachea area motion model and the heat transfer function of each wall surface, the upper airway simulation model is dynamically simulated to obtain a human upper airway model with physiological characteristics.

[0012] Preferably, the construction of the upper airway simulation model comprises the following steps:

[0013] Import real CT scan data of the human upper airway to measure the direction and radius of the cartilage rings, as well as the distance between adjacent cartilage rings;

[0014] Cartilage ring modeling is performed based on CT scan data of the human upper airway, including: determining the position of each cartilage ring by moving and rotating, and then setting up a plane perpendicular to the current position; establishing a circular ring channel by sweeping and cutting, creating fillets between the rings, and merging the entire model to complete the modeling of the cartilage ring structure model;

[0015] Based on the real human upper airway model and cartilage ring structure model, an upper airway simulation model with a cartilage ring structure is constructed.

[0016] Preferably, it also includes:

[0017] GeomagicWrap was used to obtain CT scan data and measurements of the real human upper airway; ANSYS's Spaceclaim was used to model the upper airway simulation model with a cartilage ring structure.

[0018] Preferably, the construction of the generalized glottal area motion function of each node in the glottal area comprises the following steps:

[0019] Based on the clinical measurement data of the glottis area, a generalized glottis area motion function that conforms to physiological characteristics is constructed using coordinate motion expression, with the cross-sectional area as the displacement variable, and based on the change of glottis width over time during breathing:

[0020]

[0021] Where m is the mth plane in the z direction, and are the x, y and z coordinates of the kth node on the mth plane at time t. g,r is the deformation ratio of the maximum glottal width to the glottal width in the neutral position; ± is the relationship between the node expansion and the x direction; The function represents the movement of each node in the glottal plane over time; the g(t) function represents the node displacement function, which is a time-dependent Fourier series that controls the change of x displacement over time; Describes the change in the x-displacement of the node in the glottal plane along the y-direction, It describes the change of the x displacement of the node in the glottal area along the z direction; c and d are exponential coefficients, which are used to adjust the change of the x displacement along the y direction and the z direction respectively.

[0022] Preferably, the construction of the generalized tracheal region motion function of each node in the tracheal region comprises the following steps:

[0023] Based on the CT scan images of the trachea area at different times, the displacement changes of the trachea in the x, y and z directions during breathing were determined; according to the restriction conditions of the chest cavity, the displacement ratio of the x, y and z directions was determined to be 0.375:1:1;

[0024] Based on the displacement changes in the three directions of x, y and z, a generalized tracheal regional motion function that conforms to physiological characteristics is constructed:

[0025]

[0026] in, and are the x, y and z coordinates of the kth node at time t; h(t) is the node displacement function, which is a time-dependent Fourier series that controls the displacement trend over time; ± is the relationship between the node expansion and the x, y and z directions; Δx = Δx max / 2, Δy=Δy max / 2, e, f, and l are exponential coefficients, which are used to adjust the displacement changes in the x, y, and z directions respectively.

[0027] Preferably, the wall heat transfer function between the throat and the inner surface of the trachea is:

[0028]

[0029] Where t is time, k t is the thermal conductivity of the tissue, T t is the tissue temperature, T g is the air temperature, h f is the convective heat transfer coefficient between air and tissue, H is the latent heat of vaporization of water vapor, m is the water permeability coefficient of the mucosal surface, is the relative humidity of the surrounding air, is the saturated vapor pressure at the temperature of the inhaled hot air, is the saturated vapor pressure at tissue temperature.

[0030] Preferably, the wall heat transfer function between the oral cavity and the pharynx is:

[0031]

[0032] Among them, k g is the thermal conductivity of air, h' f is the convective heat transfer coefficient between the air in the respiratory tract and the external free flow;

[0033] The wall functions at the inlet and outlet are T0 and T a ; T0 is the temperature of the inhaled external hot air; T a is the arterial blood temperature.

[0034] Preferably, it also includes:

[0035] The dynamicFvMesh method based on OpenFOAM is used to simulate the generalized glottal area motion function and the generalized tracheal area motion function in the upper airway model.

[0036] The thermoPhyscial model based on OpenFOAM is used to simulate the heat transfer functions of each wall in the upper airway model.

[0037] A system for constructing a human upper airway model with physiological characteristics, the system comprising:

[0038] processor;

[0039] a memory having stored thereon a computer program executable on the processor;

[0040] Wherein, when the computer program is executed by the processor, the steps of the method for constructing a human upper airway model with physiological characteristics are implemented.

[0041] A computer-readable storage medium stores a data processing program, which, when executed by a processor, implements the steps of the method for constructing a human upper airway model with physiological characteristics.

[0042] Beneficial effects of the present invention:

[0043] The present invention proposes a method, system and medium for constructing a human upper airway model with physiological characteristics. The method constructs a generalized glottis area motion function of each node in the glottis area, a generalized trachea area motion function of each node in the trachea area, a wall heat transfer function between the larynx and the inner surface of the trachea, a wall heat transfer function between the oral cavity and the pharynx, and a wall heat transfer function at the inlet and outlet. The method further considers the deformation of the respiratory tract during breathing and the temperature regulation of the respiratory tract wall. It can more realistically reflect the physiological characteristics of the human upper airway and generate an accurate human upper airway model. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1is a flow chart of constructing a human upper airway model with physiological characteristics according to an embodiment of the present invention;

[0045] Figure 2 is a flow chart of constructing a respiratory tract model with a cartilage ring structure according to an embodiment of the present invention;

[0046] Figure 3 is a respiratory model diagram, where Figure 3 (a) is a diagram of the respiratory tract model without the cartilage ring structure. Figure 3 (b) is a diagram of a respiratory tract model with a cartilage ring structure;

[0047] Figure 4 This is a schematic diagram of glottal changes, where: Figure 4 (a) is the position of the glottis in the z direction, Figure 4 (b) is a schematic diagram of the change in glottis width during breathing;

[0048] Figure 5 is a schematic diagram of the changes in the cross-section of the trachea, where Figure 5 (a) is a schematic diagram of the cross section of the trachea. Figure 5 (b) is a schematic diagram of the changes in the cross-section of the trachea during breathing;

[0049] Figure 6 (a) Schematic diagram of the structure of the respiratory tract, mucus layer and tissue layer; Figure 6 (b) is a schematic diagram of the movement of water vapor in the respiratory tract. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0051] Example 1

[0052] There are already many widely used respiratory models in the CFD research of respiratory mechanics, but both segmented models and full airway models tend to reflect the geometric characteristics of the respiratory tract and ignore the inherent physiological characteristics of the human respiratory tract. For the glottis-trachea movement, the static solid wall assumption is currently mainly adopted, and the deformation of the respiratory tract during breathing is not considered. For the tracheal cartilage rings, smooth walls are currently mainly used. It is assumed that the respiratory tract wall is an adiabatic wall, and the temperature regulating effect of the respiratory tract wall is not considered. The existence of these assumptions will cause some flow fields to not match the actual flow, making it difficult to obtain more accurate simulation results. Therefore, in order to simulate the process of airflow or foreign particles entering the human respiratory tract during real breathing, especially to analyze the influence of physiological characteristics on airflow and particle transport and deposition, it is necessary to construct a human upper airway model with physiological characteristics. To this end, the present invention provides a method for constructing a human upper airway model with physiological characteristics, and the specific process is as follows Figure 1 As shown, the following steps are included:

[0053] S1: Obtain CT scan data of the human upper airway; obtain the orientation and radius of the cartilage ring of the upper airway and the distance between adjacent cartilage rings according to the CT scan data, and construct an upper airway simulation model with a cartilage ring structure based on a real human upper airway model. In the prior art, the conventional real human upper airway model is a simplified model without a cartilage ring structure.

[0054] S2: Based on the change of glottal width over time during breathing, a generalized glottal area motion model is constructed.

[0055] S3: Based on the temporal changes of the tracheal displacement in three directions during breathing, a generalized tracheal regional motion model is constructed.

[0056] S4: According to the heat transfer process in the respiratory tract, the wall heat transfer function between the larynx and the inner surface of the trachea, the wall heat transfer function between the oral cavity and the pharynx, and the wall heat transfer function at the inlet and outlet are constructed.

[0057] S5: Meshing the upper airway simulation model.

[0058] S6: Based on the motion function of each node in the glottis area, the motion function of each node in the trachea area, and the heat transfer function of each wall surface, the upper airway simulation model after meshing is dynamically simulated to obtain a human upper airway model with physiological characteristics.

[0059] Furthermore, the steps for constructing the respiratory tract model with cartilage ring structure are as follows: Figure 2 As shown, the construction of the upper airway simulation model in S1 includes the following steps:

[0060] In this embodiment, Geomagic Wrap 2021 software is used to import real upper airway CT scan data of the human body, and the measurement tools in the software are used to accurately measure the orientation, radius and distance between the cartilage rings and record the data; enter ANSYS's Spaceclaim 2020R2 to model the cartilage rings of the CT scanned upper airway, mainly using the move and rotate functions to determine the position of each cartilage ring, and then set up a plane perpendicular to the current position, and use the sweep and cut function of the software to establish a circular channel, and use the fillet function to make the rings smoother, which conforms to the actual situation of the human body. Finally, the entire model is processed by the merge surface function in the repair to make the overall model smoother. The model structure is as follows Figure 3 As shown, Figure 3 (a) is a diagram of the respiratory tract model without the cartilage ring structure. Figure 3 (b) is a diagram of the respiratory tract model with a cartilage ring structure.

[0061] Furthermore, the construction of the generalized glottal area motion model in S2 specifically includes:

[0062] Based on the clinical measurement data of the glottis area, a generalized glottis area motion model that conforms to physiological characteristics was created using coordinate motion expression and cross-sectional area as the displacement variable.

[0063] During breathing, the anterior-posterior length of the glottis remains constant, while the glottis width changes over time throughout the breathing process. During inspiration, the glottis expands from its initial state to its maximum, then shrinks back to its initial state, and continues to shrink to its minimum state during expiration, then stretches back to its initial state. Figure 4 As shown, Figure 4 (a) is the position of the glottis in the z direction, Figure 4 (b) is a schematic diagram of the change in glottal width during breathing. Figure 4 (b) A, B, and C are schematic diagrams of the glottis width changing from the initial state to the maximum and then back to the initial state during inspiration, and C, D, and E are schematic diagrams of the glottis width changing from the initial state to the minimum and then back to the initial state during exhalation. Therefore, the generalized glottis area motion function is constructed as follows:

[0064]

[0065] Where m is the mth plane in the z direction, and are the x, y and z coordinates of the kth node on the mth plane at time t. g,r is the deformation ratio of the maximum glottal width to the glottal width in the neutral position; ± is the relationship between the node expansion and the x direction; The function represents the movement of each node in the glottal plane over time; the g(t) function represents the node displacement function, which is a time-dependent Fourier series that controls the change of x displacement over time; Describes the change in the x-displacement of the node in the glottal plane along the y-direction, It describes the change of the x displacement of the node in the glottal area along the z direction; c and d are exponential coefficients, which are used to adjust the change of the x displacement along the y direction and the z direction respectively.

[0066] In this embodiment, the dynamicFvMesh method of OpenFOAM open source software is used to realize the generalized glottal area motion function. Specifically, the constructed geometric model is first meshed based on the Fluent software of ANSYS, and then the mesh is transformed using fluent3DMeshToFoam, and glottisDeformarionPointPathVectorField.C and glottisDeformarionPointPathVectorField.H files are constructed based on C++ language, wherein the .C file describes the generalized glottal area motion function in detail, and the .H file provides the constant of the generalized glottal area motion function. The above-mentioned compiled dynamic library is loaded in the system / controlDict file, and the dynamicMeshDict file is added in the constant folder to call the .C and .H files.

[0067] Furthermore, the construction of the generalized tracheal regional motion model in S3 includes the following steps:

[0068] like Figure 5 As shown, Figure 5 (a) is a schematic diagram of the cross section of the trachea. Figure 5 (b) is a schematic diagram of the change of tracheal cross-section during breathing. Based on the CT scan images of the tracheal area at different times, the displacement changes of the trachea in the x, y and z directions during the entire breathing process are observed, and a generalized tracheal regional motion model that conforms to physiological characteristics is created based on the displacement changes. During the breathing process, unlike the glottis movement, the trachea expands and contracts in the x, y and z directions. Among them, the displacement ratio in the x, y and z directions is 0.375:1:1. The smaller deformation in the x direction is due to the limitation of the chest cavity. During the inhalation process, the trachea expands from the initial state to the maximum, and then contracts back to the initial state during the exhalation phase.

[0069] Based on the displacement changes in the three directions of x, y and z, a generalized tracheal regional motion function that conforms to physiological characteristics is constructed:

[0070]

[0071] in, and are the x, y and z coordinates of the kth node at time t; h(t) is the node displacement function, which is a time-dependent Fourier series that controls the displacement trend over time; ± is the relationship between the node expansion and the x, y and z directions; Δx = Δx max / 2, Δy=Δy max / 2, e, f, and l are exponential coefficients, which are used to adjust the displacement changes in the x, y, and z directions respectively.

[0072] In this embodiment, the generalized tracheal regional motion function is realized based on the dynamicFvMesh method of OpenFOAM open source software. Specifically, the constructed geometric model is first meshed based on the Fluent software of ANSYS, and then the mesh is converted using fluent3DMeshToFoam, and the tracheaDeformarionPointPathVectorField.C and tracheaDeformarionPointPathVectorField.H files are constructed based on the C++ language, wherein the .C file describes the generalized tracheal regional motion function in detail, and the .H file provides the constants of the generalized tracheal regional motion function. In order to realize the glottis and trachea motion at the same time, all the above-compiled dynamic libraries are loaded in the system / controlDict file, and the dynamicMeshDict file is added to the constant file to call all the .C and .H files at the same time.

[0073] Furthermore, the heat transfer process in the respiratory tract includes evaporative heat dissipation on the respiratory tract surface, convective heat transfer between the respiratory tract and tissues, and thermal balance within the tissues. Figure 6 (a) is a schematic diagram of the structure of the respiratory tract, mucus layer and tissue layer. The movement of water vapor in the respiratory tract is shown in Figure 2. Figure 6 As shown in (b), a mucus layer is attached to the junction of the respiratory tract and tissues. There is a large amount of water in the mucus layer. The respiratory tract inhales air carrying heat, which evaporates the water in the mucus layer. Evaporative heat dissipation occurs on the respiratory tract-tissue surface, taking away the heat in the hot air. There is a temperature difference between the tissue and the hot air. The hot air in the respiratory tract will transfer part of the heat to the respiratory tract tissue through convection heat exchange. The blood circulation inside the tissue will dissipate part of the heat, and the metabolic process will generate heat. The heat balance in the tissue is determined by the two parameters of blood perfusion and metabolic rate. Therefore, according to the above thermal interaction process in the respiratory tract, a respiratory heat transfer model that meets the physiological conditions of the human body is established.

[0074] In S4, the heat generation and heat dissipation of tissues in the throat and trachea were observed to regulate the temperature distribution of hot air in the respiratory tract and the temperature of the respiratory tract-tissue surface. The wall heat transfer between the throat and the inner surface of the trachea was based on the water evaporation heat dissipation and convection heat transfer on the inner surface of the throat and trachea. The wall heat transfer function was:

[0075]

[0076] Where t is time, k t is the thermal conductivity of the tissue, T t is the tissue temperature, T g is the air temperature, h f is the convective heat transfer coefficient between air and tissue, H is the latent heat of vaporization of water vapor, m is the water permeability coefficient of the mucosal surface, is the relative humidity of the surrounding air, is the saturated vapor pressure at the temperature of the inhaled hot air, is the saturated vapor pressure at tissue temperature.

[0077] Since the oral cavity is the first to come into contact with hot air, the heat dissipation effect of the tissue itself is not obvious. Therefore, the wall heat transfer function between the oral cavity and the pharynx is:

[0078]

[0079] Among them, k g is the thermal conductivity of air, h' f is the convective heat transfer coefficient between the air in the respiratory tract and the external free flow;

[0080] The wall functions at the inlet and outlet are:

[0081] Entrance: T g1 =T0

[0082] Export: T g2 =T a

[0083] Where T0 is the temperature of the inhaled external hot air; T a is the arterial blood temperature.

[0084] In this embodiment, the wall heat transfer function of the upper airway is realized based on the thermophysical model of the OpenFOAM open source software. Specifically, the wallthermophysical.C and wallthermophysical.H files are constructed based on the C++ language, the T file is added to the 0 folder, and the wall heat transfer function is set in the corresponding wall boundary. The thermophysicalProperties is added to the constant file to call the required heat transfer model and the changed file.

[0085] The above is a method for constructing a human upper airway model with physiological characteristics provided by one embodiment of the present embodiment. Based on the same idea, the present embodiment also provides a corresponding system for constructing a human upper airway model with physiological characteristics. For the specific definition of the system for constructing a human upper airway model with physiological characteristics, please refer to the definition of the method for constructing a human upper airway model with physiological characteristics in the above text, which will not be repeated here. Each module in the above-mentioned system for constructing a human upper airway model with physiological characteristics can be implemented in whole or in part through software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory in the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above-mentioned modules.

[0086] This embodiment also provides a computer-readable storage medium, which stores a computer program, which can be used to execute the above Figure 1 A method for constructing a human upper airway model with physiological characteristics is provided.

[0087] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory or optical memory, etc. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0088] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for constructing a human upper airway model with physiological characteristics, characterized in that: The following steps are involved: Acquire CT scan data of the human upper airway; acquire the orientation and radius of the cartilage ring of the upper airway and the distance between adjacent cartilage rings according to the CT scan data, and construct an upper airway simulation model with a cartilage ring structure based on a real human upper airway model; According to the change of glottal width over time during breathing, a generalized glottal regional motion model is constructed; According to the time-varying displacement of the trachea in three directions during breathing, a generalized tracheal regional motion model is constructed. According to the heat transfer process in the respiratory tract, the wall heat transfer function between the larynx and the inner surface of the trachea, the wall heat transfer function between the oral cavity and the pharynx, and the wall heat transfer function at the inlet and outlet are constructed; Based on the generalized glottis area motion model, the generalized trachea area motion model and the heat transfer function of each wall surface, the upper airway simulation model is dynamically simulated to obtain a human upper airway model with physiological characteristics.

2. The method for constructing a human upper airway model with physiological characteristics according to claim 1, characterized in that: The construction of the upper airway simulation model comprises the following steps: Import real CT scan data of the human upper airway to measure the direction and radius of the cartilage rings, as well as the distance between adjacent cartilage rings; Cartilage ring modeling is performed based on CT scan data of the human upper airway, including: determining the position of each cartilage ring by moving and rotating, and then setting up a plane perpendicular to the current position; establishing a circular ring channel by sweeping and cutting, creating fillets between the rings, and merging the entire model to complete the modeling of the cartilage ring structure model; Based on the real human upper airway model and cartilage ring structure model, an upper airway simulation model with a cartilage ring structure is constructed.

3. The method for constructing a human upper airway model with physiological characteristics according to claim 2, characterized in that: Also includes: Use GeomagicWrap to perform real CT scan data and measurements of the human upper airway; ANSYS Spaceclaim was used to model the upper airway simulation model with a cartilage ring structure.

4. The method for constructing a human upper airway model with physiological characteristics according to claim 1, characterized in that: The construction of the generalized glottal area motion model comprises the following steps: Based on the clinical measurement data of the glottis area, a generalized glottis area motion function that conforms to physiological characteristics is constructed using coordinate motion expression, with the cross-sectional area as the displacement variable, and based on the change of glottis width over time during breathing: Where m is the mth plane in the z direction, and are the x, y and z coordinates of the kth node on the mth plane at time t; d g,r is the deformation ratio of the maximum glottal width to the glottal width in the neutral position; ± is the relationship between the node expansion and the x direction; The function represents the movement of each node in the glottal plane over time; the g(t) function represents the node displacement function, which is a time-dependent Fourier series that controls the change of x displacement over time; Describes the change in the x-displacement of the node in the glottal plane along the y-direction, It describes the change of the x displacement of the node in the glottal area along the z direction; c and d are exponential coefficients, which are used to adjust the change of the x displacement along the y direction and the z direction respectively.

5. The method for constructing a human upper airway model with physiological characteristics according to claim 4, characterized in that: The construction of the generalized tracheal regional motion model comprises the following steps: Based on the CT scan images of the trachea area at different times, the displacement changes of the trachea in the x, y and z directions during breathing were determined; according to the restriction conditions of the chest cavity, the displacement ratio of the x, y and z directions was determined to be 0.375:1:1; Based on the displacement changes in the three directions of x, y and z, a generalized tracheal regional motion function that conforms to physiological characteristics is constructed: in, and are the x, y and z coordinates of the kth node at time t; h(t) is the node displacement function, which is a time-dependent Fourier series that controls the displacement trend over time; ± is the relationship between the node expansion and the x, y and z directions; Δx = Δx max / 2, Δy=Δy max / 2, e, f, and l are exponential coefficients, which are used to adjust the displacement changes in the x, y, and z directions respectively.

6. The method for constructing a human upper airway model with physiological characteristics according to claim 5, characterized in that: The wall heat transfer function between the throat and the inner surface of the trachea is: Where t is time, k t is the thermal conductivity of the tissue, T t is the tissue temperature, T g is the air temperature, h f is the convective heat transfer coefficient between air and tissue, H is the latent heat of vaporization of water vapor, m is the water permeability coefficient of the mucosal surface, is the relative humidity of the surrounding air, is the saturated vapor pressure at the temperature of the inhaled hot air, is the saturated vapor pressure at tissue temperature.

7. The method for constructing a human upper airway model with physiological characteristics according to claim 6, characterized in that: The wall heat transfer function between the oral cavity and the pharynx is: Among them, k g is the thermal conductivity of air, h' f is the convective heat transfer coefficient between the air in the respiratory tract and the external free flow; The wall functions at the inlet and outlet are T0 and T a ; T0 is the temperature of the inhaled external hot air; T a is the arterial blood temperature.

8. The method for constructing a human upper airway model with physiological characteristics according to claim 7, characterized in that: Also includes: The dynamicFvMesh method based on OpenFOAM is used to simulate the generalized glottal area motion function and the generalized tracheal area motion function in the upper airway model. The thermoPhyscial model based on OpenFOAM is used to simulate the heat transfer functions of each wall in the upper airway model.

9. A system for constructing a human upper airway model with physiological characteristics, characterized in that: The system comprises: processor; a memory having stored thereon a computer program executable on the processor; Wherein, when the computer program is executed by the processor, the steps of the method for constructing a human upper airway model with physiological characteristics as described in any one of claims 1 to 8 are implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a data processing program, and when the data processing program is executed by a processor, the steps of the method for constructing a human upper airway model with physiological characteristics as described in any one of claims 1 to 8 are implemented.

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