Burn prediction method based on CFD secondary development of UDF self-defined model

Abstract

The application relates to the technical field of human body protection, and discloses a burn prediction method based on a CFD secondary development UDF self-defined model, which comprises the following steps: a heat-mass coupling transfer model among the human skin of a rescuer, a high-temperature environment and a fire suit is established; a corresponding self-defined model is created for the heat-mass coupling transfer model in the CFD, so that the heat-mass coupling transfer model is converted from one dimension to three dimensions, and the heat-mass transfer condition of the rescuer in the three-dimensional high-temperature environment is obtained; a numerical dummy model is established according to the human physiological structure of the rescuer, and a heat reaction model for reflecting the heat physiological reaction of the rescuer in the high-temperature environment is established; the numerical dummy model, the heat reaction model and the three-dimensional heat-mass coupling transfer model are coupled in the CFD, and the heat-mass transfer condition and the heat physiological reaction of each human body part of the rescuer in the three-dimensional high-temperature environment are simulated, so that the burn prediction effect of the human skin of the rescuer in the high-temperature environment is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of human body protection, and in particular to a burn prediction method and device based on CFD secondary development of a UDF self-defined model, equipment and a medium. BACKGROUND

[0002] When rescue personnel fight a fire, the high-temperature thermal radiation environment in which they are located can cause the rescue personnel to be burned, and even threaten their life safety. Therefore, real-time prediction of the burn condition of rescue personnel in a high-temperature thermal radiation environment is of great significance to improving rescue efficiency and protecting the life safety of firefighters.

[0003] At present, burn prediction is generally performed by simulating the thermal response and thermal damage of rescue personnel in a high-temperature thermal radiation environment. However, the thermal physiological response and thermal damage of the human body are greatly affected by environmental conditions and differences in body parts. Even under the same environmental conditions, the skin temperature of each part of the human body will show differences, resulting in poor prediction of the burn condition of rescue personnel in a high-temperature thermal radiation environment. SUMMARY

[0004] The purpose of the present application is to provide a burn prediction method and device based on CFD secondary development of a UDF self-defined model, equipment and a medium, which can improve the prediction of the burn condition of rescue personnel in a high-temperature thermal radiation environment.

[0005] To solve the above technical problems, an embodiment of the present application provides a high-temperature environment human skin burn prediction method, comprising the following steps:

[0006] According to the heat transfer process between the human skin of the rescue personnel, the high-temperature environment and the fire suit, and the influence of the mass transfer phenomenon of the water in the fire suit on the heat transfer process, a heat-mass coupled transfer model between the human skin of the rescue personnel, the high-temperature environment and the fire suit is established;

[0007] According to the secondary development UDF function in computational fluid dynamics CFD, a corresponding self-defined model is created for the heat-mass coupled transfer model in CFD, so as to convert the heat-mass coupled transfer model from a one-dimensional heat-mass coupled transfer model to a three-dimensional heat-mass coupled transfer model; wherein the three-dimensional heat-mass coupled transfer model is used to reflect the heat-mass transfer of the rescue personnel in a three-dimensional high-temperature environment;

[0008] According to the physiological structure of the human body of the rescue personnel, a numerical dummy model is established;

[0009] A thermal response model for reflecting the thermal physiological response of the rescue personnel in a high-temperature environment is established;

[0010] The numerical dummy model of the rescue personnel, the thermal reaction model and the three-dimensional heat-mass coupled transfer model are coupled in the CFD to simulate the heat-mass transfer conditions and the thermal physiological reactions of each body part of the rescue personnel in the three-dimensional high-temperature environment, so as to predict the skin burn of the rescue personnel in the high-temperature environment.

[0011] In some optional embodiments, the numerical dummy model of the rescue personnel, the thermal reaction model and the three-dimensional heat-mass coupled transfer model are coupled in the CFD to simulate the heat-mass transfer conditions and the thermal physiological reactions of each body part of the rescue personnel in the three-dimensional high-temperature environment, including:

[0012] In the CFD, the following steps are iteratively run:

[0013] The skin temperature of each body part of the rescue personnel is obtained by the thermal reaction model as the temperature boundary value of the corresponding body part of the numerical dummy model, and the numerical dummy model is controlled to run according to the temperature boundary value by the three-dimensional heat-mass coupled transfer model to obtain the heat-mass transfer conditions between each body part of the rescue personnel and the high-temperature environment;

[0014] The heat-mass transfer conditions between each body part of the rescue personnel and the high-temperature environment are fed back to the thermal reaction model to obtain the thermal physiological reactions of different body parts of the rescue personnel.

[0015] In some optional embodiments, the heat transfer process between the skin of the human body, the high-temperature environment and the fire-fighting clothes includes heat conduction, heat radiation and heat convection, and the mass transfer phenomenon of the water in the fire-fighting clothes includes evaporation, condensation, adsorption, desorption, diffusion and convection.

[0016] In some optional embodiments, the heat transfer process conforms to the following energy conservation equation:

[0017]

[0018] In the formula, ρ eff represents the effective density of each layer of fabric of the fire-fighting clothes and the high-temperature environment, kg / m 3 ; (c p ) eff represents the effective specific heat of each layer of fabric and the high-temperature environment, J / (kg·K); k eff represents the effective thermal conductivity, W / (m·K); △h vap and △h abs respectively represent the evaporation enthalpy per unit mass and the conversion enthalpy of bound water in the fabric to free liquid water, J / kg; m vs represents the mass conversion rate of water vapor to bound water, kg / (m3·s); q rad is the incident heat radiation flux on the surface of the outer fabric, W / m 2 ; Kfab extinction coefficient of the fabric, m -1 .

[0019] In some alternative embodiments, before the coupling of the numerical dummy model of the rescue personnel, the thermal reaction model and the three-dimensional thermal-mass coupling transfer model, further comprising:

[0020] According to the human physiological structure of the rescue personnel, the numerical dummy model of the rescue personnel is divided into a plurality of human body part models; wherein each human body part model comprises a skin layer, a muscle layer, a fat layer and a core layer.

[0021] In some alternative embodiments, the heat transfer process of each human body part model and the skin layer, the muscle layer, the fat layer and the core layer of each human body part model conforms to the following heat balance equation:

[0022]

[0023] In the formula, i represents the number of human body part models, j represents the skin layer, the muscle layer, the fat layer or the core layer of each human body part model, C represents the heat capacity of the human body part, T i,j represents the temperature of the jth layer in the ith human body part model, t represents the time when the human body is exposed to the environment, Q i,j represents the heat production of the jth layer in the ith human body part model, B i,j represents the blood heat exchange of the jth layer in the ith human body part model, D i,j represents the conductive heat exchange between the jth layer and other different layers in the ith human body part model, Res represents the respiratory heat transfer, Rad, Con and Eva respectively represent the radiation, convection and evaporation heat transfer between the human body and the environment.

[0024] In some alternative embodiments, the thermal physiological reaction of the rescue personnel includes: skin temperature, core temperature, sweat flow rate and blood flow rate.

[0025] Embodiments of the present application also provide a burn prediction device based on CFD secondary development of UDF self-defined model, comprising:

[0026] The first model establishment module is used to establish a thermal-mass coupling transfer model between the human skin of the rescue personnel, the high-temperature environment and the fire-fighting clothes according to the heat transfer process between the human skin of the rescue personnel, the high-temperature environment and the fire-fighting clothes in the high-temperature environment and the influence of the mass transfer phenomenon of water in the fire-fighting clothes on the heat transfer process;

[0027] The first model processing module is configured to create a corresponding custom model for the heat-mass coupled transfer model in computational fluid dynamics (CFD) according to a user-defined function (UDF) in the CFD, so as to convert the heat-mass coupled transfer model from a one-dimensional heat-mass coupled transfer model to a three-dimensional heat-mass coupled transfer model, wherein the three-dimensional heat-mass coupled transfer model is used to reflect heat-mass transfer of the rescue personnel in a three-dimensional high-temperature environment.

[0028] The second model establishing module is configured to establish a numerical dummy model according to a human physiological structure of the rescue personnel.

[0029] The third model establishing module is configured to establish a heat reaction model for reflecting a heat physiological reaction of the rescue personnel in the high-temperature environment.

[0030] The human burn prediction module is configured to couple the numerical dummy model, the heat reaction model and the three-dimensional heat-mass coupled transfer model of the rescue personnel in the CFD, simulate heat-mass transfer and heat physiological reaction of each human body part of the rescue personnel in the three-dimensional high-temperature environment, and predict a human skin burn condition of the rescue personnel in the high-temperature environment.

[0031] Embodiments of the present application also provide a computer device, comprising at least one processor, and a memory in communication connection with the at least one processor, wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the high-temperature environment human skin burn prediction.

[0032] Embodiments of the present application also provide a computer readable storage medium storing a computer program, and the computer program is executed by a processor to implement the high-temperature environment human skin burn prediction.

[0033] The burn prediction method based on the CFD UDF custom model provided by the present application has at least the following beneficial effects:

[0034] In the present application, not only the heat physiological reaction of the rescue personnel in the high-temperature environment is reflected by the established heat reaction model, but also the heat transfer process among the human skin of the rescue personnel, the high-temperature environment and the fire-fighting clothes in the high-temperature environment, and the influence of the mass transfer phenomenon of the water in the fire-fighting clothes on the heat transfer process are considered, and based on this, the heat-mass coupled transfer model among the human skin of the rescue personnel, the high-temperature environment and the fire-fighting clothes is established, and the numerical dummy model established according to the human physiological structure of the rescue personnel and the heat reaction model for reflecting the heat physiological reaction of the rescue personnel in the high-temperature environment are coupled to predict the human skin burn condition, and the prediction effect is better.

[0035] And, in the present application, the UDF function in the computational fluid dynamics CFD is used to create a corresponding custom model for the heat-mass coupled transfer model in the CFD, so as to convert the heat-mass coupled transfer model from one dimension to three dimensions, so that when coupled with the numerical dummy model and the thermal reaction model, the heat-mass transfer and thermal physiological reaction of each human body part in a three-dimensional high-temperature environment can be effectively simulated, the difference in skin burn of different human body parts in a high-temperature environment is considered, and the prediction effect of human skin burn is further improved. BRIEF DESCRIPTION OF DRAWINGS

[0036] One or more embodiments are illustrated by way of example with reference to the drawings, which are not intended to be limiting of the embodiments.

[0037] Figure 1 is a flow chart of a burn prediction method based on a CFD secondary development UDF custom model according to an embodiment of the present application;

[0038] Figure 2 is a system structure schematic diagram of a burn prediction based on a CFD secondary development UDF custom model according to an embodiment of the present application;

[0039] Figure 3 is a CFD secondary development UDF custom model and human thermal reaction model coupling system output result schematic diagram according to an embodiment of the present application;

[0040] Figure 4 is a coupling schematic diagram of a CFD secondary development UDF custom model and a human thermal reaction model according to an embodiment of the present application;

[0041] Figure 5 is a schematic diagram of a burn prediction device based on a CFD secondary development UDF custom model according to an embodiment of the present application;

[0042] Figure 6 is a structure schematic diagram of a computer device according to an embodiment of the present application. DETAILED DESCRIPTION

[0043] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the embodiments of the present application will be described in detail below with reference to the drawings. However, those skilled in the art can understand that, in the embodiments of the present application, many technical details are presented in order to make the readers better understand the present application. However, the technical solutions claimed by the present application can be implemented even without these technical details and various changes and modifications based on the following embodiments. The division of the following embodiments is for the convenience of description, and should not constitute any limitation on the specific implementation modes of the present application, and the embodiments can be combined and referenced with each other under the premise of no contradiction.

[0044] One embodiment of the present application relates to a burn prediction method based on CFD secondary development of a UDF self-defined model. The implementation details of the burn prediction based on CFD secondary development of a UDF self-defined model in the embodiment will be described in detail below. The following details are provided for the convenience of understanding, and are not essential for implementing the present solution.

[0045] The specific process of the burn prediction method based on CFD secondary development of a UDF self-defined model in the embodiment can be as shown in Figure 1 , which includes:

[0046] In step 101, a heat-mass coupled transfer model between human skin, high-temperature environment and fire-fighting clothes of a rescuer is established according to the heat transfer process between human skin, high-temperature environment and fire-fighting clothes of the rescuer in a high-temperature environment and the influence of the mass transfer phenomenon of water in the fire-fighting clothes on the heat transfer process.

[0047] Specifically, the heat transfer process between human skin, high-temperature environment and fire-fighting clothes includes several heat transfers such as heat conduction, heat radiation and heat convection. When entering a fire-fighting rescue scene, the rescuer is inevitably wetted by water from the inside or outside. The water in the fire-fighting clothes (fabric) mainly absorbs or releases heat in the forms of evaporation, condensation, adsorption, desorption, diffusion and convective mass transfer, which will have certain influence on the above heat transfer process, that is, the mass transfer phenomenon of water in the fire-fighting clothes includes evaporation, condensation, adsorption, desorption, diffusion and convection. Combining the above factors, a heat-mass coupled transfer model between human skin, high-temperature environment and fire-fighting clothes of the rescuer in a high-temperature environment can be established.

[0048] In a specific implementation, the above heat conduction, heat radiation and heat convection belong to sensible heat transfer, and the phase change, adsorption and desorption of water in the fabric belong to latent heat change. The heat-mass transfer is one-dimensional, and free liquid water does not exist on the surface of the skin or in the fabric layer; the change of water content in the fabric will not cause volume expansion or contraction, and the different phases in the fabric are always in a local thermodynamic equilibrium state, and the water vapor density in the high-temperature environment is always in a uniform state.

[0049] The heat transfer process of the human skin-high temperature environment-firefighter clothing system under the fire environment belongs to unsteady heat transfer, and the heat radiation emitted by the heat source only penetrates the outer fabric, and the heat is one-dimensionally transferred along the thickness direction of the fabric. According to the physical properties, the system can be divided into different layers, and the energy conservation equation of each layer is constructed, the initial and boundary conditions are set, and the solving process is realized in MATLAB.

[0050] The energy conservation equation is as follows:

[0051]

[0052] In the formula, ρ eff represents the effective density of each layer of fabric of the firefighter clothing and the high temperature environment, kg / m 3 ; (c p ) eff represents the effective specific heat of each layer of fabric and the high temperature environment, J / (kg·K); k eff represents the effective thermal conductivity, W / (m·K); △h vap and △h abs respectively represent the evaporation enthalpy per unit mass and the conversion enthalpy of bound water to free liquid water in the fabric, J / kg; m vs represents the mass conversion rate of water vapor to bound water, kg / (m3·s); q rad is the incident heat radiation flux on the surface of the outer fabric, W / m 2 ; K fab is the extinction coefficient of the fabric, m -1 .

[0053] In step 102, according to the secondary development UDF function in computational fluid dynamics CFD, a corresponding custom model is created for the heat and mass coupled transfer model in CFD, so as to convert the heat and mass coupled transfer model from a one-dimensional heat and mass coupled transfer model to a three-dimensional heat and mass coupled transfer model; wherein the three-dimensional heat and mass coupled transfer model is used to reflect the heat and mass transfer of the rescue personnel in the three-dimensional high temperature environment.

[0054] In step 103, a numerical dummy model is established according to the human physiological structure of the rescue personnel.

[0055] In step 104, a thermal reaction model is established for reflecting the thermal physiological reaction of the rescue personnel in the high temperature environment.

[0056] In step 105, the numerical dummy model, the thermal reaction model and the three-dimensional heat and mass coupled transfer model of the rescue personnel are coupled in CFD, and the heat and mass transfer of each part of the rescue personnel in the three-dimensional high temperature environment and the thermal physiological reaction are simulated to predict the human skin burn of the rescue personnel in the high temperature environment.

[0057] Specifically, in the CFD, the following steps are iteratively run: obtaining the skin temperature of each body part of the rescuer by the thermal reaction model as the temperature boundary value of the corresponding body part of the numerical dummy model, and controlling the numerical dummy model to run according to the temperature boundary value by the three-dimensional thermal-mass coupling transfer model to obtain the thermal-mass transfer between each body part of the rescuer and the high-temperature environment; feeding back the thermal-mass transfer between each body part of the rescuer and the high-temperature environment to the thermal reaction model to obtain the thermal physiological response of different body parts of the rescuer, thereby predicting the skin burn of the rescuer in the high-temperature environment.

[0058] In a specific implementation, the thermal-mass coupling transfer model of the rescuer is converted into C language code, and a corresponding custom model is created for the thermal-mass coupling transfer model in the CFD according to the User-Defined Function (UDF) function in the Computational Fluid Dynamics (CFD). UDF is a mechanism for extending the functions of a database or data processing system, allowing users to write their own functions according to specific needs to perform specific calculations or logical operations. The thermal reaction model can obtain the skin temperature of different body parts of the rescuer through preset parameters, which are used as the temperature boundary value of the corresponding body part of the numerical dummy model. Then, the above preset parameters are controlled by the custom model, so that the numerical dummy model is controlled to run according to the temperature boundary value to obtain the heat exchange between different body parts of the rescuer and the high-temperature environment, and the heat exchange between different body parts of the rescuer and the high-temperature environment is fed back to the thermal reaction model to obtain the thermal physiological response of different body parts of the rescuer. By repeatedly iterating the above process, the changes in heat exchange and thermal physiological response between the human body and the high-temperature environment at different times can be obtained.

[0059] The thermal-mass coupling transfer model related to the thermal-mass coupling transfer mechanism is a MATLAB code, which can be converted into an independent C language code by MatlabCoder, and then a custom model is created using the UDF function of the CFD. The numerical dummy model refers to the human body geometry model obtained by three-dimensional laser scanning of a thermal mannequin, which is divided into multiple parts using ICEM software according to the physiological structure of the human body, and the divided numerical dummy is placed in a virtual climate chamber, and then the virtual climate chamber and the numerical dummy are meshed using ICEM software.

[0060] In obtaining the thermal physiological response of the rescuer, the thermal physiological response includes skin temperature, core temperature, sweat flow rate, and blood flow rate.

[0061] In one example, before coupling the numerical dummy model, thermal response model, and three-dimensional heat and mass transfer model of the rescuer, the numerical dummy model of the rescuer is first divided into multiple human body part models, for example, 20 human body parts, based on the human physiological structure of the rescuer. Each human body part model includes a skin layer, muscle layer, fat layer, and core layer. By constructing heat balance equations for each layer of each human body part, the heat and mass transfer between the human body and the environment can be quantitatively expressed.

[0062] At this point, the heat transfer process of each human body part model, as well as the skin layer, muscle layer, fat layer, and core layer of each human body part model, conforms to the following heat balance equation:

[0063]

[0064] In the formula, i represents the number of human body part models, j represents the skin layer, muscle layer, fat layer, or core layer of each human body part model, C represents the heat capacity of the human body part, and T represents the heat capacity of the human body part. i,j Let Q represent the temperature of the j-th layer in the i-th human body part model, t represent the time the human body is exposed to the environment, and Q represent the temperature of the j-th layer in the model. i,j B represents the heat generation of the j-th layer in the i-th human body part model. i,j D represents the heat exchange of blood in the j-th layer of the i-th human body part model. i,j Res represents the conductive heat exchange between the j-th layer and other different layers in the i-th human body part model, Res represents the respiratory heat transfer, and Rad, Con, and Eva represent the radiation, convection, and evaporative heat transfer between the human body and the environment, respectively.

[0065] This embodiment not only considers the thermophysiological response of rescue personnel in high-temperature environments through the established thermal response model, but also the heat transfer process between the rescuer's skin, the high-temperature environment, and the fire suit, as well as the influence of mass transfer of moisture in the fire suit on the aforementioned heat transfer process. Based on this, a thermo-mass coupling transfer model between the rescuer's skin, the high-temperature environment, and the fire suit is established. This model is coupled with a numerical dummy model based on the rescuer's physiological structure and a thermal response model reflecting the rescuer's thermophysiological response in high-temperature environments to predict skin burns, resulting in better prediction performance. Furthermore, this embodiment utilizes the secondary development UDF function in Computational Fluid Dynamics (CFD) to create a corresponding custom model in CFD for the thermo-mass coupling transfer model, thereby converting the thermo-mass coupling transfer model from one-dimensional to three-dimensional. When coupled with the numerical dummy model and the thermal response model, it can effectively simulate the thermo-mass transfer and thermophysiological response of various parts of the rescuer's body in a three-dimensional high-temperature environment, taking into account the differences in skin burns in different parts of the body under high-temperature conditions, further improving the prediction effect of skin burns.

[0066] In one embodiment, the burn prediction method based on the CFD secondary development UDF custom model of the present application can be implemented through a system structure as shown in the figure, which is a CFD secondary development UDF custom model and human thermal response model coupling system. Meanwhile, the present embodiment also provides Figure 2 and Figure 3 and Figure 4 which respectively show the output results of the CFD secondary development UDF custom model and human thermal response model coupling system and the process of the CFD secondary development UDF custom model and human thermal response model coupling system.

[0067] Among them, the heat-mass coupling transfer mechanism, including the skin-microenvironment-firefighter clothing system heat transfer model considering thermal radiation, thermal convection, thermal conduction, provides the basis for the establishment of the heat-mass coupling model; considering the influence of mass transfer phenomena such as phase change, adsorption and desorption of water in fabric on heat transfer and skin burn, a skin-microenvironment-firefighter clothing heat-mass coupling transfer model is established. UDF custom function, convert the heat-moisture coupling transfer model into C language code, create a custom model using the CFD secondary development UDF function. CFD simulation coupling calculation system, coupling numerical manikin and human thermal response model, embed it into fluid dynamics analysis CFD, use the custom model to control the model parameters or calculation process in the Fluent calculation process. Three-dimensional full-size thermal injury and thermal physiological prediction block, through the CFD simulation coupling calculation system, output the results of heat exchange and thermal physiological reflection of each part of the human body at different times.

[0068] Since the CFD simulation coupling algorithm is a repeatable test evaluation method, it can flexibly set the virtual environment working condition, and overcome the individual difference of human experiment and the danger of extreme thermal radiation environment experiment. Therefore, the present embodiment develops the CFD simulation coupling three-dimensional full-size algorithm and human thermal response model coupling system, refines the skin temperature distribution of each part, realizes the skin burn prediction in high temperature environment, and the real-time evaluation of human thermal physiological parameters is more targeted.

[0069] In a specific example, assuming that the ambient temperature is 300K, the initial temperature of the multi-layer fabric of the fire suit and the high-temperature environment is consistent with the ambient temperature, and the initial temperature of the skin layer linearly increases from the epidermis to the subcutaneous tissue (305.65-306.65K), the model is solved using MATLAB software, the program language is converted to C language through the Matlab coder conversion program, and a custom model is created using the UDF function of CFD secondary development. The geometry of the thermal manikin is obtained through three-dimensional scanning technology, the human body thermal response model is coupled, the model after segmentation is placed in a virtual climate chamber, the mesh of the coupled model of the virtual climate chamber and the manikin is divided, the model algorithm in the Fluent calculation process is controlled using UDF, the boundary condition temperature is set, the turbulent intensity is 5%, the simulation is simulated by ANSYS software, the skin temperature, core temperature, sweat flow rate, blood flow rate and the like are obtained, the iterative calculation process is repeated, and changes in human body thermal injury and thermal physiological response at different times are obtained. The overall and local skin burn time of the human body is judged according to the Stoll second-degree burn criterion. The results are as follows: with the increase of exposure time, the skin temperature increases, the temperature gradually exceeds 44℃, and the second-degree burn occurs in the head, upper arm, lower leg, foot, thigh, hip, chest, forearm, back and hand in turn. The core temperature shows a small rising or falling trend with the ambient temperature, and the measured value is 37.38℃ at the end of simulation.

[0070] It can be understood that the working conditions such as "setting the ambient temperature to 300K", "setting the boundary condition temperature", "turbulent intensity 5%" are only for the convenience of describing the present application and simplifying the description, and the specific experimental working conditions need to be set according to the actual fire scene.

[0071] The step division of the above methods is only for the purpose of clear description, and in actual implementation, one step can be combined or some steps can be split and decomposed into multiple steps, as long as the same logical relationship is included, and all are within the protection scope of the present application; adding irrelevant modifications or introducing irrelevant designs in the algorithm or flow, but not changing the core design of the algorithm and flow are within the protection scope of the present application.

[0072] Another embodiment of the present application relates to a burn prediction device based on a CFD secondary development UDF custom model, and the implementation details of the burn prediction device based on the CFD secondary development UDF custom model of the present embodiment will be specifically described below. The following content is only provided for the implementation details for the convenience of understanding, and is not necessary for implementing the present scheme. The schematic diagram of the burn prediction device based on the CFD secondary development UDF custom model of the present embodiment can be as follows: Figure 5As shown, it comprises: a first model establishing module 501, a first model processing module 502, a second model establishing module 503, a third model establishing module 504, and a human body burn prediction module 505.

[0073] Specifically, the first model establishing module 501 is configured to establish a heat-mass coupled transfer model between human skin, high-temperature environment and fire-fighting clothes of a rescuer according to heat transfer process among human skin, high-temperature environment and fire-fighting clothes of the rescuer in a high-temperature environment and influence of mass transfer phenomenon of water in the fire-fighting clothes on the heat transfer process.

[0074] The first model processing module 502 is configured to create a corresponding custom model for the heat-mass coupled transfer model in computational fluid dynamics (CFD) according to a user-defined function (UDF) in the CFD, so as to convert the heat-mass coupled transfer model from a one-dimensional heat-mass coupled transfer model to a three-dimensional heat-mass coupled transfer model; wherein the three-dimensional heat-mass coupled transfer model is configured to reflect heat-mass transfer conditions of the rescuer in a three-dimensional high-temperature environment.

[0075] The second model establishing module 503 is configured to establish a numerical dummy model according to a human physiological structure of the rescuer.

[0076] The third model establishing module 504 is configured to establish a heat reaction model for reflecting a heat physiological reaction of the rescuer in the high-temperature environment.

[0077] The human body burn prediction module 505 is configured to couple the numerical dummy model, the heat reaction model and the three-dimensional heat-mass coupled transfer model of the rescuer in the CFD, simulate heat-mass transfer conditions and heat physiological reactions of each human body part of the rescuer in the three-dimensional high-temperature environment, and predict a human skin burn condition of the rescuer in the high-temperature environment.

[0078] It can be found that the embodiment corresponds to the method embodiment, and the embodiment can be implemented in cooperation with the method embodiment. The related technical details and technical effects mentioned in the above embodiments are still valid in the embodiment, and details are not repeated here. Accordingly, the related technical details mentioned in the embodiment can also be applied to the above embodiments.

[0079] It is worth mentioning that each module involved in the embodiment is a logical module. In actual application, one logical unit can be one physical unit, a part of one physical unit, or a combination of multiple physical units. In addition, in order to highlight the innovative part of the application, units not closely related to solving the technical problems proposed in the application are not introduced in the embodiment, but this does not mean that there are no other units in the embodiment.

[0080] Another embodiment of the present application relates to a computer device, like Figure 6 as shown, comprising: at least one processor 601; and a memory 602 connected with the at least one processor 601 in communication; wherein the memory 602 stores instructions executable by the at least one processor 601, and the instructions are executed by the at least one processor 601 to enable the at least one processor 601 to perform the burn prediction method based on the CFD secondary development UDF custom model in each of the above embodiments.

[0081] The memory and the processor are connected in a bus mode, and the bus can include any number of interconnected buses and bridges, and the bus connects various circuits of one or more processors and memories together. The bus can also connect various other circuits such as peripheral devices, voltage stabilizers and power management circuits, which are well known in the art, and therefore, they will not be further described herein. The bus interface provides an interface between the bus and the transceiver. The transceiver can be one element or multiple elements, such as multiple receivers and transmitters, which provide a unit for communicating with various other devices on the transmission medium. The data processed by the processor is transmitted on the wireless medium through the antenna, and further, the antenna also receives data and transmits the data to the processor.

[0082] The processor is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interface, voltage regulation, power management and other control functions. And the memory can be used to store the data used by the processor in the execution operation.

[0083] Another embodiment of the present application relates to a computer readable storage medium, which stores a computer program. The computer program is executed by the processor to implement the method embodiments described above.

[0084] That is, those skilled in the art can understand that all or part of the steps of the above-mentioned embodiment methods can be completed by programs instructing related hardware, and the programs are stored in a storage medium, including a plurality of instructions for enabling a device (which can be a single-chip microcomputer, a chip, etc.) or a processor to execute all or part of the steps of the method described in each embodiment of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (Read-Only Memory, ROM for short), a random access memory (Random Access Memory, RAM for short), a magnetic disk or an optical disk, and various storage program codes.

[0085] Those skilled in the art can understand that the above-mentioned embodiments are specific embodiments for implementing the present application, and various changes can be made in form and details in practical application without departing from the spirit and scope of the present application.

Claims

1. A burn prediction method based on a custom UDF model developed through CFD secondary development, characterized in that, include: Based on the heat transfer process between human skin, high temperature environment, and fire suit in high temperature environment, and the influence of mass transfer of moisture in fire suit on the heat transfer process, a heat-mass coupling transfer model between human skin, high temperature environment, and fire suit of rescuers is established. Based on the secondary development UDF function in Computational Fluid Dynamics (CFD), a corresponding custom model is created in CFD to transform the heat and mass coupling transfer model from a one-dimensional heat and mass coupling transfer model to a three-dimensional heat and mass coupling transfer model; wherein, the three-dimensional heat and mass coupling transfer model is used to reflect the heat and mass transfer situation of rescuers in a three-dimensional high-temperature environment. A numerical dummy model was established based on the human physiological structure of rescue personnel; Establish a thermal response model to reflect the thermophysiological responses of rescue personnel in high-temperature environments; In CFD, a numerical dummy model, a thermal response model, and a three-dimensional thermo-mass coupling and transfer model of rescue personnel are coupled to simulate the thermo-mass transfer and thermo-physiological response of various parts of the rescue personnel's body in a three-dimensional high-temperature environment, so as to predict the skin burn situation of rescue personnel in high-temperature environments. The heat transfer process conforms to the following energy conservation equation: In the formula, ρ eff This indicates the effective density of each layer of fabric in a fire suit in high-temperature environments, expressed in kg / m³. 3 ;( c p ) eff This represents the effective specific heat of each layer of fabric in a high-temperature environment, in J / (kg·K); k eff The effective thermal conductivity is expressed in W / (m·K); Δ h vap and △ h abs The enthalpy of evaporation and the enthalpy of transition from bound water to free liquid water in the fabric are respectively expressed in J / kg; m vs This represents the mass conversion rate of water vapor to bound water, expressed in kg / (m³). 3 ·s); q rad The incident thermal radiation flux on the surface of the outer fabric layer, W / m 2 ; K fab m is the extinction coefficient of the fabric. -1 .

2. The burn prediction method based on a custom UDF model developed through CFD secondary development according to claim 1, characterized in that, The numerical dummy model, thermal response model, and three-dimensional thermo-mass coupling model of rescue personnel in CFD are coupled to simulate the thermo-mass transfer and thermophysiological response of each part of the rescue personnel's body in a three-dimensional high-temperature environment, including: In CFD, the following steps are iteratively executed: The skin temperature of each part of the rescuer's body is obtained by the thermal reaction model and used as the temperature boundary value of the corresponding part of the numerical dummy model. The numerical dummy model is controlled to run according to the temperature boundary value by the three-dimensional thermal-mass coupling and transfer model to obtain the thermal-mass transfer between each part of the rescuer's body and the high-temperature environment. The heat and mass transfer between different parts of the rescuers' bodies and the high-temperature environment is fed back into the thermal response model to obtain the thermophysiological responses of different parts of the rescuers' bodies.

3. The burn prediction method based on a custom UDF model developed through CFD secondary development according to claim 1, characterized in that, The heat transfer process between human skin, the high-temperature environment, and the fire suit includes heat conduction, heat radiation, and heat convection. The mass transfer phenomena of moisture in the fire suit include evaporation, condensation, adsorption, desorption, diffusion, and convection.

4. The burn prediction method based on a custom UDF model developed through CFD secondary development according to claim 1, characterized in that, Before the numerical dummy model, thermal response model, and three-dimensional heat-mass coupling and transfer model of the coupled rescue personnel, the following is also included: Based on the human physiological structure of rescuers, the numerical dummy model of rescuers is divided into multiple human body part models; each human body part model includes a skin layer, muscle layer, fat layer and core layer.

5. The burn prediction method based on a custom UDF model developed through CFD secondary development according to claim 4, characterized in that, The heat transfer processes of each of the aforementioned human body part models, as well as the skin, muscle, fat, and core layers of each model, conform to the following heat balance equation: In the formula, i Indicates the number of human body part models. j This refers to the skin layer, muscle layer, fat layer, or core layer of each human body part model. C Indicates the heat capacity of a part of the human body. T i,j Indicates the first i The first in the personal body part model j The temperature of each layer, t Indicates the duration of human exposure to the environment. Q i,j Indicates the first i The first in the personal body part model j The heat generation of each layer B i,j Indicates the first i The first in the personal body part model j Blood heat exchange in each layer D i,j Indicates the first i The first in the personal body part model j Heat exchange through conduction between each layer and other different layers. Res This indicates heat transfer through respiration. Rad , Con and Eva These represent the heat exchange between the human body and the environment through radiation, convection, and evaporation, respectively.

6. The burn prediction method based on a custom UDF model developed through CFD secondary development according to any one of claims 1 to 5, characterized in that, The thermophysiological responses of the rescuers include: skin temperature, core temperature, sweat flow rate, and blood flow.

7. A burn prediction device based on a custom UDF model developed through CFD secondary development, characterized in that, include: The first model building module is used to establish a heat-mass coupling transfer model between the human skin, the high-temperature environment, and the fire suit of rescuers in a high-temperature environment, based on the heat transfer process between the human skin, the high-temperature environment, and the fire suit, as well as the influence of the mass transfer phenomenon of moisture in the fire suit on the heat transfer process. The first model processing module is used to create a corresponding custom model in CFD for the heat-mass coupling and transfer model based on the secondary development UDF function in computational fluid dynamics (CFD), so as to convert the heat-mass coupling and transfer model from a one-dimensional heat-mass coupling and transfer model to a three-dimensional heat-mass coupling and transfer model; wherein, the three-dimensional heat-mass coupling and transfer model is used to reflect the heat-mass transfer situation of rescuers in a three-dimensional high-temperature environment. The second model building module is used to build a numerical dummy model based on the human physiological structure of rescue personnel. The third model building module is used to build a thermal response model that reflects the thermophysiological response of rescuers in high-temperature environments. The human burn prediction module is used to couple the numerical dummy model, thermal response model and three-dimensional thermo-mass coupling and transfer model of rescuers in CFD to simulate the thermo-mass transfer and thermo-physiological response of each part of the rescuer's body in a three-dimensional high-temperature environment, so as to predict the human skin burn situation of rescuers in high-temperature environments. The heat transfer process conforms to the following energy conservation equation: In the formula, ρ eff This indicates the effective density of each layer of fabric in a fire suit in high-temperature environments, expressed in kg / m³. 3 ;( c p ) eff This represents the effective specific heat of each layer of fabric in a high-temperature environment, in J / (kg·K); k eff The effective thermal conductivity is expressed in W / (m·K); Δ h vap and △ h abs The enthalpy of evaporation and the enthalpy of transition from bound water to free liquid water in the fabric are respectively expressed in J / kg; m vs This represents the mass conversion rate of water vapor to bound water, expressed in kg / (m³). 3 ·s); q rad The incident thermal radiation flux on the surface of the outer fabric layer, W / m 2 ; K fab m is the extinction coefficient of the fabric. -1 .

8. A computer device, characterized in that, include: At least one processor; And a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to execute the burn prediction method based on a CFD secondary development UDF custom model as described in any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the burn prediction method based on the CFD secondary development UDF custom model as described in any one of claims 1 to 6.

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