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

Abstract

The present invention provides a method, system, and medium for constructing a human upper airway model with physiological characteristics, relating to the technical field of respiratory model construction, including: obtaining CT scan data of the human upper airway to construct an upper airway simulation model with a cartilage ring structure; constructing a generalized glottis regional motion model based on the time-varying glottis width during breathing; constructing a generalized glottis regional motion model based on the time-varying displacement of the trachea in three directions during breathing; constructing a respiratory heat transfer model based on the heat transfer process within the respiratory tract; constructing a wall heat transfer function between the larynx and the inner surface of the trachea, as well as a wall heat transfer function between the oral cavity and the pharynx; and dynamically simulating the upper airway simulation model based on multiple motion functions and wall heat transfer functions. The model construction method takes into account the deformation of the respiratory tract during breathing and the temperature regulation of the respiratory tract wall, and can construct an accurate human upper airway model.

Description

Technical Field

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

[0002] The human respiratory process exhibits complex physiological characteristics, such as the cyclical expansion and contraction of the glottis, the cyclical expansion and contraction of the trachea with its cartilaginous rings, and heat transfer along the respiratory wall. These physiological characteristics influence the study of airflow and particle deposition within the respiratory tract. Establishing a mathematical model that can describe the physiological characteristics of the upper airway will greatly facilitate simulation and analysis of airflow characteristics within the respiratory tract during real breathing, furthering our understanding of the physiological functions of the human respiratory system. Therefore, it is necessary to establish an upper airway model that closely resembles the physiological characteristics of the real respiratory system.

[0003] Although there are many widely used respiratory tract models in CFD research on respiratory mechanics, 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. This 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 objectives, 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] Obtain CT scan data of the human upper airway; obtain the orientation and radius of the cartilage rings of the upper airway, as well as the distance between adjacent cartilage rings based on 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 time-varying changes of glottis width during breathing, a generalized glottis regional motion model is constructed.

[0009] According to the temporal changes of the tracheal displacement 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 functions 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 human upper airway CT scan data to measure the orientation and radius of 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. This involves: determining the position of each cartilage ring by moving and rotating it, then establishing a plane perpendicular to the current position; establishing circular channels through sweeping excision, creating fillets between the rings, and merging the entire model to complete the cartilage ring structure modeling.

[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, 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 motion 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 region along the z-direction; c and d are exponential coefficients used to adjust the change of the x-displacement along the y-direction and the z-direction, respectively.

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

[0023] Based on CT scan images of the trachea at different times, the displacement changes of the trachea in the x, y, and z directions during breathing were determined. Based on the constraints of the chest cavity, the displacement ratio of the three 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 inhaled hot air temperature, 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, as well as 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. It further considers the deformation of the airway during breathing and the temperature regulation of the airway wall, and 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 for constructing a human upper airway model with physiological characteristics according to an embodiment of the present invention;

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

[0046] Figure 3 is a diagram of the respiratory tract model, where 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;

[0047] Figure 4 This is a 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 glottal 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 tracheal cross-section during breathing;

[0049] Figure 6 (a) Schematic diagram 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 solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to 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 intended to limit the present invention.

[0051] Example 1

[0052] There are already many widely used respiratory models in the study of respiratory mechanics CFD, 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 glottal-tracheal movement, the static solid wall assumption is currently mainly adopted, and the deformation of the respiratory tract during breathing is not considered. For 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; determine the orientation and radius of the cartilage rings of the upper airway, as well as the distance between adjacent cartilage rings, based on the CT scan data. A simulation model of the upper airway with the cartilage ring structure is constructed based on a real human upper airway model. Conventional real human upper airway models are simplified models without the cartilage ring structure.

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

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

[0056] S4: Based on the heat transfer process in the respiratory tract, construct 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 functions at the inlet and outlet.

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

[0058] S6: Based on the motion functions of each node in the glottis area, the motion functions of each node in the trachea area, and the heat transfer functions of each wall surface, the meshed upper airway simulation model 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 human upper airway CT scan data through the software, 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 is in line with the real 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 is 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 showing the glottis width changing from initial state to maximum expansion and then contraction during inspiration, while C, D, and E are schematic diagrams showing the glottis width changing from initial state to contraction to minimum expansion and then back to initial state during expiration. 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 motion 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 region along the z-direction; c and d are exponential coefficients 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 implement the generalized glottal area motion function. Specifically, the constructed geometric model is first meshed based on ANSYS's Fluent software, and then the mesh is converted using fluent3DMeshToFoam. The glottisDeformarionPointPathVectorField.C and glottisDeformarionPointPathVectorField.H files are constructed based on the C++ language, where the .C file describes the generalized glottal area motion function in detail, and the .H file provides the constants 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 to 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) Schematic diagram of the changes in the tracheal cross-section during breathing. Based on CT scan images of the tracheal region at different times, the displacement changes of the trachea in the x, y, and z directions throughout the breathing process were observed. Based on the displacement changes, a generalized tracheal regional motion model that conforms to physiological characteristics was created. During breathing, unlike the movement of the glottis, the trachea expands and contracts in the x, y, and z directions. 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 restriction of the chest cavity. During inspiration, the trachea expands from its initial state to its maximum, and then contracts back to its initial state during expiration.

[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 implemented based on the dynamicFvMesh method of the 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. The tracheaDeformarionPointPathVectorField.C and tracheaDeformarionPointPathVectorField.H files are constructed based on the C++ language. Among them, 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 glottal and tracheal motion at the same time, all the dynamic libraries compiled above 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, convection 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 adheres to the interface between the respiratory tract and tissues. This layer contains a large amount of water. Heat-carrying air is inhaled into the respiratory tract, causing the water in the mucus layer to evaporate. This evaporative heat dissipation occurs at the respiratory tract-tissue interface, removing heat from the heated air. Due to the temperature difference between the tissue and the heated air, the heated air in the respiratory tract transfers some of this heat to the respiratory tissues through convection. Blood circulation within the tissues dissipates some of this heat, while metabolic processes generate heat. The thermal balance within the tissues is determined by two parameters, blood perfusion and metabolic rate. Therefore, based on these thermal interactions within the respiratory tract, a respiratory heat transfer model that conforms to human physiological conditions was established.

[0074] In S4, the effects of tissue heat generation and heat dissipation on the temperature distribution of hot air in the respiratory tract and the regulation of the respiratory tract-tissue surface temperature were observed in the larynx and trachea. The wall heat transfer between the larynx and trachea inner surface was based on water evaporation and convection heat transfer on the larynx and trachea inner surface. 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 inhaled hot air temperature, is the saturated vapor pressure at tissue temperature.

[0077] Since the oral cavity is the first to be exposed to 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] Among them, T0 is the temperature of the inhaled external hot air; T a is the arterial blood temperature.

[0084] In this example, the wall heat transfer function for the upper airway is implemented based on the thermophysical model in the open-source OpenFOAM software. Specifically, the wallthermophysical.c and wallthermophysical.h files are constructed in C++, a T file is added to the 0 folder, and the wall heat transfer function is set on the corresponding wall boundary. The thermophysicalProperties file is added to the constant file to call the required heat transfer model and the modified file.

[0085] The above is a method for constructing a human upper airway model with physiological characteristics provided by one embodiment of this embodiment. Based on the same idea, this 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 above, 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 fully or partially implemented by 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 of 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 that can be used to execute the above Figure 1 Provided is a method for constructing a human upper airway model with physiological characteristics.

[0087] Those skilled in the art will understand that all or part of the processes in the above-mentioned embodiment methods can be implemented 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), 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 scope of protection 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: Obtain CT scan data of the human upper airway; obtain the orientation and radius of the cartilage rings of the upper airway, as well as the distance between adjacent cartilage rings based on 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 time-varying changes of glottis width during breathing, a generalized glottis regional motion model is constructed. According to the temporal changes of the tracheal displacement 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 functions 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; The construction of the upper airway simulation model comprises the following steps: Import real human upper airway CT scan data to measure the orientation and radius of 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. This involves: determining the position of each cartilage ring by moving and rotating it, then establishing a plane perpendicular to the current position; establishing circular channels through sweeping excision, creating fillets between the rings, and merging the entire model to complete the cartilage ring structure modeling. 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.

2. The method for constructing a human upper airway model with physiological characteristics according to claim 1, 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.

3. The method for constructing a human upper airway model with physiological characteristics according to claim 1, characterized in that: The construction of the generalized glottis area motion model includes 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, cross-sectional area as the displacement variable, and based on the change of glottis width over time during breathing: in, m for z The direction of m plane, , and Respectively m On the plane k Nodes in t Moment x , y and z coordinate; d g,r is the deformation ratio of the maximum glottal width to the glottal width in the neutral position; Expand and x Directional relationships; The function represents the motion of each node in the glottal plane over time; Function represents the node displacement function, which is a time-dependent Fourier series that controls x Variation of displacement with time; Describes the nodes in the glottal plane x Displacement along y Changes in direction, Describes the glottal region nodes x Displacement along z changes in direction; c and d are exponential coefficients, used to adjust x Displacement along y Direction and z Change of direction.

4. The method for constructing a human upper airway model with physiological characteristics according to claim 3, characterized in that: The construction of the generalized tracheal regional motion model includes the following steps: Based on the CT scan images of the trachea area at different times, the trachea during breathing is determined x , y and z Displacement changes in three directions; according to the constraints of the chest cavity, determine x , y and z The displacement ratio in the three directions is 0.375:1:1; based on x , y and z The displacement changes in three directions construct a generalized tracheal regional motion function that conforms to physiological characteristics: in, ， and Respectively k Nodes in t Moment x , y and z coordinate; is the node displacement function, which is a time-dependent Fourier series that controls the displacement trend over time; Expand and x , y and z Directional relationships; = , = , ; e , f , l are exponential coefficients, which are used to adjust x , y , z Directional displacement change.

5. The method for constructing a human upper airway model with physiological characteristics according to claim 4, characterized in that: The wall heat transfer function between the throat and the inner surface of the trachea is: in, t For 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 inhaled hot air temperature, is the saturated vapor pressure at tissue temperature.

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 oral cavity and the pharynx is: in, k g is the thermal conductivity of air, 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: Entrance: exit: in, is the temperature of the inhaled outside hot air; is the arterial blood temperature.

7. The method for constructing a human upper airway model with physiological characteristics according to claim 6, 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.

8. 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 7 are implemented.

9. A computer-readable storage medium, characterized in that The 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 according to any one of claims 1 to 7.

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