A method for modifying wall boundary conditions to reflect the catalytic radiation temperature change effect of heat-resistant materials

Abstract

The present invention discloses a wall boundary condition correction method that reflects the catalytic radiation temperature-dependent effects of heat-shielding materials. This method, which belongs to the field of numerical calculation, includes the following steps: based on the correlation data of the catalytic coefficient and radiative emissivity of different heat-shielding materials with the wall temperature, a temperature-dependent function of the thermal radiation emissivity and catalytic coefficient, material properties, and wall temperature is obtained by fitting; these two functions are then substituted into the radiation equilibrium boundary condition in the viscous wall temperature boundary condition and the finite rate catalytic boundary condition in the viscous wall component boundary condition; these two temperature-dependent functions are used to simulate the wall catalytic reaction and radiative heat dissipation effects of real heat-shielding materials, thereby more realistically reflecting the chemical reaction process on the wall. The present invention can accurately predict the catalytic radiation intrinsic properties of heat-shielding materials in harsh aerodynamic thermal environments.

Description

Technical Field

[0001] The present invention relates to the field of numerical calculation, and more specifically, to a wall boundary condition correction method reflecting the catalytic radiation temperature change effect of heat-proof materials. Background Art

[0002] In the numerical calculation of high-temperature non-equilibrium flow fields and surface aerodynamic heat in near-space vehicles, heat flow control can be achieved through catalytic composite effect regulation and surface radiation cooling. The Navier-Stokes equations and wall chemical reaction models require the determination of viscous wall boundary conditions. High-temperature non-equilibrium viscous wall boundary conditions can generally be divided into temperature boundary conditions (given temperature or heat flux, radiation balance) and component boundary conditions (complete catalysis, complete non-catalysis, and finite rate catalysis). However, existing passive thermal protection methods that consider material catalytic radiation usually use a given constant radiation emissivity and wall catalytic coefficient, without considering the temperature-dependent effects of the catalytic and radiation coefficients of the thermal protection material. This leads to problems such as redundant design of the thermal protection system and excessive weight of the thermal protection structure, making it difficult to meet the development needs of future aircraft. Summary of the Invention

[0003] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a wall boundary condition correction method that reflects the catalytic radiation temperature change effect of heat-shielding materials, which can accurately predict the catalytic radiation intrinsic properties of heat-shielding materials in harsh aerodynamic thermal environments.

[0004] The object of the present invention is achieved through the following solutions:

[0005] A wall boundary condition correction method reflecting the catalytic radiation temperature change effect of heat-resistant materials includes the following steps:

[0006] Based on the correlation data of the catalytic coefficient and radiation emissivity of different heat-resistant materials with the wall temperature, the temperature-varying function of the thermal radiation emissivity, material properties and wall temperature is obtained by fitting, and the temperature-varying function of the catalytic coefficient, material properties and wall temperature is obtained by fitting;

[0007] These two temperature variation functions are then substituted into the radiation equilibrium boundary condition in the viscous wall temperature boundary condition, and the finite rate catalytic boundary condition in the viscous wall component boundary condition; these two temperature variation functions are used to simulate the wall catalytic reaction and radiation heat dissipation effect of real thermal protection materials, thereby more realistically reflecting the chemical reaction process on the wall.

[0008] Furthermore, the temperature variation function of thermal radiation emissivity, material properties and wall temperature is specifically:

[0009] ;

[0010] in, eis the radiation emissivity, is the fitting coefficient, is the wall temperature.

[0011] Furthermore, the temperature variation function of the catalytic coefficient, material properties, and wall temperature is specifically:

[0012] ;

[0013] in, is the catalytic coefficient, is the fitting coefficient, is the wall temperature.

[0014] Furthermore, the method of obtaining the temperature-dependent function of the thermal radiation emissivity, the material properties, and the wall temperature by fitting the data related to the catalytic coefficient and the radiation emissivity of different heat-resistant materials and the wall temperature, and obtaining the temperature-dependent function of the catalytic coefficient, the material properties, and the wall temperature by fitting, specifically includes the following sub-steps:

[0015] Step a, obtaining experimentally determined data on the correlation between the catalytic coefficient and the radiation emissivity of the heat-shielding material and the wall temperature;

[0016] Step b, using a three-parameter mathematical fitting method to convert the data obtained in step a into a corresponding temperature variation function form, including:

[0017] The wall temperature of the heat protection material Convert to the corresponding dimensionless value , then the radiation emissivity in step a is e and The temperature variation function is , M represents material, 、 、 is the fitting coefficient; then the radiation emissivity e and The function is defined so that it satisfies ; Among them, when the wall temperature value is less than or equal to the minimum temperature value of the emissivity experiment When the radiation emissivity is taken as the minimum temperature value of the emissivity experiment Calculate the value of the temperature variation function of the independent variable , 、 、 is the fitting coefficient; when the wall temperature is greater than or equal to the maximum temperature value of the emissivity experiment When the radiation emissivity is taken as the maximum temperature value of the emissivity experiment Calculate the value of the temperature variation function of the independent variable , 、 、 is the fitting coefficient; when the wall temperature is at the minimum temperature of the emissivity experiment Maximum temperature value of emissivity experiment When the radiation emissivity is between Calculate the value of the temperature variation function of the independent variable , 、 、 is the fitting coefficient;

[0018] The catalytic coefficient and The temperature variation function is ;in, 、 、 is the fitting coefficient.

[0019] Furthermore, the two temperature variation functions are substituted into the radiation equilibrium boundary condition in the viscous wall temperature boundary condition and the finite rate catalytic boundary condition in the viscous wall component boundary condition respectively; the wall catalytic reaction and radiation heat dissipation effect of the real heat-resistant material are simulated by these two temperature variation functions, thereby more realistically reflecting the chemical reaction process on the wall, which specifically includes the following sub-steps:

[0020] In step c, the two temperature variation function relationships in step b are substituted into the radiation equilibrium boundary condition in the viscous wall boundary condition and the finite rate catalytic boundary condition in the viscous wall component boundary condition; the calculation does not consider the internal structure heat conduction and material ablation reaction, and only considers the surface thermal radiation effect and catalytic effect. Then the wall energy conservation equation is:

[0021] ;

[0022] in, For gas components s The heat flow caused by the wall temperature gradient, is the total number of incoming gas component types, For gas components s Heat flow due to diffusion, is the wall radiation heat flux; where the components s The wall temperature gradient, heat flux caused by component diffusion, and radiation heat flux are:

[0023] ;

[0024] ;

[0025] ;

[0026] in, is the Boltzmann constant, is the thermal conductivity of the gas near the wall, n is the normal direction of the wall, is the total density of the incoming gas, For gas components s The equivalent diffusion coefficient, For gas components s The absolute enthalpy, For gas components s The quality score, is the incoming gas temperature;

[0027] Catalytic coefficient By affecting the catalytic reaction rate constant k w,s Indirectly affects component diffusion heat flow and catalytic reaction rate constant k w,s and catalytic coefficient c The relationship between them is:

[0028] ;

[0029] in, is the Boltzamnn constant, take , For gas components s molar mass;

[0030] Step d, flow field initialization, in the i =1 time step, preset number of inner loop steps j =0, the wall temperature is T w , and the actual heat flow is calculated from this Q and estimated heat flow Q es :

[0031] ;

[0032] ;

[0033] Among them, take ;

[0034] The actual heat flow Q and estimated heat flow Q es Convert to the corresponding value and , then the temperature change for:

[0035] ;

[0036] Then update the wall temperature preset value to , " "Indicates iterative update to determine whether or inner loop times j If the set value is satisfied, exit the inner loop, otherwise j = j +1, and continue to execute the inner loop. is the minimum calculated residual;

[0037] Step e, the time step moves forward one step, that is, at the time step i = i +1 inside, execute the inner loop.

[0038] Furthermore, in step e, the time-marching method uses the LU-SGS implicit method to advance the solution of the Navier-Stokes equations considering chemical reaction flow until the second norm of the full-field density between two adjacent time steps is less than the set value of two, and the flow field reaches a stable exit cycle, that is, the aircraft wall temperature and heat flux results are obtained.

[0039] The beneficial effects of the present invention include:

[0040] The core advantage of the method of the present invention is that it innovatively considers the coupling effect between the aerodynamic thermal environment and the heat-shielding material. Specifically, a temperature-dependent function of the catalytic coefficient and the radiation emissivity, which is related to the material properties and accurately fitted based on the experimental data of catalytic radiation of the heat-shielding material, is introduced. This improvement significantly improves the accuracy of the boundary conditions. Compared with the traditional method of setting the catalytic coefficient and the radiation emissivity as constants, it effectively reduces the error between the numerical calculation and the actual high-temperature surface effect of the heat-shielding material. Through this precise prediction, the scheme of the present invention can provide strong support for the design and engineering application of aircraft thermal protection systems, help optimize the selection and application of heat-shielding materials, and ensure the safety and reliability of aircraft under extreme conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0042] Figure 1 This is a flow chart for solving high-temperature non-equilibrium flow with viscous wall boundary conditions considering the temperature variation effect of catalytic radiation in the embodiment of the present invention;

[0043] Figure 2 The heat flux distribution curve of the wall of different materials. DETAILED DESCRIPTION

[0044] All features disclosed in all embodiments in this specification, or steps in all methods or processes implicitly disclosed, except for mutually exclusive features and / or steps, can be combined and / or expanded or replaced in any manner.

[0045] In light of the aforementioned issues, the inventors of this invention believe it is necessary to establish a viscous wall boundary condition for numerical calculations of aerodynamic heat on high-temperature non-equilibrium flow surfaces based on the temperature-dependent effects of the catalytic and emissivity coefficients of heat-shielding materials. This allows for coupling between the aerodynamic thermal environment and the heat-shielding material, thereby reducing the error between the numerical calculations of existing coupled solvers and the high-temperature surface effects of the heat-shielding material. The specific implementation process of this invention is as follows:

[0046] In the technical concept of the present invention, the material wall catalytic reaction process involved can be divided into multiple independent and time-related reaction mechanisms. First, the atoms in the dissociated atmosphere diffuse to the surface of the material, and the diffusion mechanism can be expressed by the modified Fick's law; then, the reaction atoms reach the surface of the material and undergo chemical or physical adsorption and react with atoms in the gas phase (Eley-Rideal mechanism, referred to as ER mechanism) or move to the vicinity of another adsorbed atom (Langumir-Hinschelwood mechanism, referred to as LH mechanism) to recombine into molecules, leave the surface after desorption, and diffuse into the gas phase. The diffusion process depends only on the kinetic properties of the mobile component, and the adsorption, surface recombination reaction and desorption process are related to the chemical properties of the material surface. Since the recombination reaction is an exothermic reaction, a large amount of chemical energy will be released on the surface, thereby increasing the surface heat flux density and further aggravating the surface heat load. This heat load generated by the catalytic reaction depends on the atomic recombination rate and the released chemical energy, and is usually expressed by the catalytic coefficient. c Characterizes the strength of the wall catalytic properties. Catalytic coefficient c It is based on the definition of the catalytic reaction process as the ratio of the number of recombined atoms that collide with the surface to the total number of atoms that collide with the surface. c reflects the rate of surface recombination reactions. c Between 0 (completely non-catalytic) and 1 (completely catalytic), changes in the material wall temperature can significantly affect the catalytic coefficient. c .

[0047] In the technical solution of the present invention, the temperature boundary condition involved is the surface thermal radiation balance, based on the Stefan-Boltzmann law of non-black bodies:

[0048] (1);

[0049] in, s is the Boltzmann constant, whose value is ; is the radiation emissivity e and wall temperature The temperature function of e It is defined as the ratio of the radiation power of an object to the radiation power of a black body under the same temperature and conditions. e Its value is between 0 and 1. Emissivity is a key parameter that characterizes the radiation ability of an object. It directly affects the energy transfer efficiency of the object during the thermal radiation process. represents the wall temperature, is the incoming gas temperature, is the heat flux on the aircraft wall. Figure 2 The heat flux distribution curve of the wall of different materials.

[0050] Changes in the surface temperature of the heat shield material can significantly affect the catalytic coefficient c and radiant emissivity e Therefore, the present invention achieves accurate numerical solution of aircraft wall temperature and heat flux by adding catalytic and radiation coefficients related to heat-shielding materials and wall temperature, while considering the wall catalytic reaction and thermal radiation heat dissipation effect of real heat-shielding materials.

[0051] The surface thermal radiation balance boundary condition mainly considers the radiation heat exchange between the wall and the surrounding environment. Function (where M Indicates material, T w Represents the wall temperature), which can more accurately calculate the radiation heat flux of different heat-resistant materials at different wall temperatures. The finite rate catalytic boundary condition focuses on the catalytic reaction occurring on the wall. Function (where M Indicates material, T w represents the wall temperature), which can accurately simulate the changes of different heat-resistant wall components in the catalytic reaction, thereby more realistically reflecting the chemical reaction process on the wall.

[0052] Specifically, the present invention modifies the original viscous high temperature non-equilibrium flow viscous wall boundary conditions to solve the wall temperature and heat flow. Figure 1 Specifically, a wall boundary condition correction method reflecting the catalytic radiation temperature change effect of heat-resistant materials is provided, which mainly includes the following steps:

[0053] Step a: Obtain experimentally measured data on the catalytic coefficient and thermal radiation emissivity of a typical heat shield material in relation to wall temperature. This data is typically obtained through precise experimental measurements and accurately reflects the catalytic composite reaction and thermal radiation cooling effect of different heat shield materials at different temperatures.

[0054] Step b, using the three-parameter mathematical fitting method, convert these data into a function form that can more accurately describe the physical properties of a specific material under high temperature conditions, and convert the wall temperature of the heat-resistant material into Convert to the corresponding dimensionless value That is, at this time, the radiation emissivity ε is proportional to the wall Temperature function , which refers to the temperature-dependent function of the radiation emissivity of a certain material M and the wall temperature. The specific form is:

[0055] (2)

[0056] Where M represents the material, 、 、 is the fitting coefficient;

[0057] and the catalytic coefficient and The temperature variation function is:

[0058] (3);

[0059] in, 、 、 is the fitting coefficient.

[0060] To ensure that the radiation emissivity meets the requirements in the entire temperature range , define the function of radiative emissivity and wall temperature. Specifically, when the wall temperature is less than or equal to the minimum temperature value of the emissivity experiment When the radiation emissivity is taken as the minimum temperature value of the emissivity experiment Calculate the value of the temperature variation function of the independent variable , 、 、 is the fitting coefficient; when the wall temperature is greater than or equal to the maximum temperature value of the emissivity experiment When the radiation emissivity is taken as the maximum temperature value of the emissivity experiment Calculate the value of the temperature variation function of the independent variable , 、 、 is the fitting coefficient; when the wall temperature is at the minimum temperature of the emissivity experiment Maximum temperature value of emissivity experiment When the radiation emissivity is between Calculate the value of the temperature variation function of the independent variable , 、 、 is the fitting coefficient. The final specific form after definition is:

[0061] (4);

[0062] in, and They are the minimum temperature value and the maximum temperature value of the emissivity experiment, that is, the minimum and maximum values of the wall temperature corresponding to the radiation emissivity data of the specific heat-shielding material measured in the experiment.

[0063] Step c: Substitute these two temperature function relationships into the radiation balance boundary condition in the viscous wall boundary condition and the finite rate catalytic boundary condition. The calculation does not consider the internal structure heat conduction and material ablation reaction, but only considers the surface thermal radiation effect and catalytic effect, that is, the surface thermal radiation balance. The wall energy conservation equation is:

[0064] (5);

[0065] in, For gas components s The heat flow caused by the wall temperature gradient, is the total number of incoming gas component types, For gas components s Heat flow due to diffusion, The heat flux is the heat dissipated by wall radiation.

[0066] In the formula, the gas components s The wall temperature gradient, heat flux caused by component diffusion, and radiation heat flux are:

[0067] (6);

[0068] (7);

[0069] (8);

[0070] in, is the thermal conductivity of the gas near the wall, n is the normal direction of the wall, is the total density of the incoming gas, For gas components s The equivalent diffusion coefficient, For gas components s The absolute enthalpy, For gas components s quality score.

[0071] Catalytic coefficient By affecting the catalytic reaction rate constant kw,s Indirectly affects the component diffusion heat flow, when c When it increases, the catalytic reaction rate accelerates, and the consumption or generation rate of the components on the wall increases, thereby affecting the mass fraction gradient of the components. , thereby changing the diffusion heat flow. The catalytic reaction rate constant k w,s and catalytic coefficient c The relationship between them is:

[0072] ;

[0073] in, is the Boltzamnn constant, take , For gas components s molar mass;

[0074] Step d, flow field initialization, in the i =1 time step, preset number of inner loop steps j =0, the wall temperature is T w , from which the actual heat flow can be calculated Q and estimated heat flow Q es ,

[0075] (10);

[0076] (11);

[0077] in, is the incoming gas temperature, is the Boltzmann constant, take ;

[0078] The actual heat flow Q and estimated heat flow Q es Convert to the corresponding value and , then the temperature change for:

[0079] (12);

[0080] The wall temperature preset value is updated to , " "Indicates iterative update to determine whether or inner loop times j If the set value is satisfied, exit the inner loop, otherwise j = j +1, and continue to execute the inner loop. Minimize the calculated residual.

[0081] Step e, then the time step moves forward one step, that is, at time step i = i +1, the inner loop is executed, and the LU-SGS implicit method is used in the time advancement method to advance the solution of the Navier-Stokes equations considering chemical reaction flow until the second norm of the full-field density between two adjacent time steps is less than the set value, and the flow field reaches stability and exits the loop, and the results such as the aircraft wall temperature and heat flux can be obtained.

[0082] It should be noted that within the scope of protection defined in the claims of the present invention, the following embodiments can be combined and / or expanded or replaced in any logical way from the above specific implementation methods, such as disclosed technical principles, disclosed technical features or implicitly disclosed technical features.

[0083] Example 1

[0084] A wall boundary condition correction method reflecting the catalytic radiation temperature change effect of heat-resistant materials includes the following steps:

[0085] Based on the correlation data of the catalytic coefficient and radiation emissivity of different heat-resistant materials with the wall temperature, the temperature-varying function of the thermal radiation emissivity, material properties and wall temperature is obtained by fitting, and the temperature-varying function of the catalytic coefficient, material properties and wall temperature is obtained by fitting;

[0086] These two temperature variation functions are then substituted into the radiation equilibrium boundary condition in the viscous wall temperature boundary condition, and the finite rate catalytic boundary condition in the viscous wall component boundary condition; these two temperature variation functions are used to simulate the wall catalytic reaction and radiation heat dissipation effect of real thermal protection materials, thereby more realistically reflecting the chemical reaction process on the wall.

[0087] Example 2

[0088] Based on Example 1, the temperature variation function of thermal radiation emissivity, material properties, and wall temperature is specifically as follows:

[0089] ;

[0090] in, e is the radiation emissivity, is the fitting coefficient, is the wall temperature.

[0091] Example 3

[0092] Based on Example 1, the temperature variation function of the catalytic coefficient, material properties, and wall temperature is specifically as follows:

[0093] ;

[0094] in, is the catalytic coefficient, is the fitting coefficient, is the wall temperature.

[0095] Example 4

[0096] On the basis of Example 1, the method of fitting the temperature-varying function of the thermal radiation emissivity, material properties, and wall temperature based on the relevant data of the catalytic coefficient and radiation emissivity of different heat-proof materials and the wall temperature, and fitting the temperature-varying function of the catalytic coefficient, material properties, and wall temperature, specifically includes the following sub-steps:

[0097] Step a, obtaining experimentally determined data on the correlation between the catalytic coefficient and the radiation emissivity of the heat-shielding material and the wall temperature;

[0098] Step b, using a three-parameter mathematical fitting method to convert the data obtained in step a into a corresponding temperature variation function form, including:

[0099] The wall temperature of the heat protection material Convert to the corresponding dimensionless value , then the radiation emissivity in step a is e and The temperature variation function is , M represents material, 、 、 is the fitting coefficient; then the radiation emissivity e and The function is defined so that it satisfies ; Among them, when the wall temperature value is less than or equal to the minimum temperature value of the emissivity experiment When the radiation emissivity is taken as the minimum temperature value of the emissivity experiment Calculate the value of the temperature variation function of the independent variable , 、 、 is the fitting coefficient; when the wall temperature is greater than or equal to the maximum temperature value of the emissivity experiment When the radiation emissivity is taken as the maximum temperature value of the emissivity experiment Calculate the value of the temperature variation function of the independent variable , 、 、 is the fitting coefficient; when the wall temperature is at the minimum temperature of the emissivity experiment Maximum temperature value of emissivity experiment When the radiation emissivity is between Calculate the value of the temperature variation function of the independent variable , 、 、 is the fitting coefficient;

[0100] The catalytic coefficient and The temperature variation function is ;in, 、 、 is the fitting coefficient.

[0101] Example 5

[0102] Based on Example 4, the two temperature variation functions are substituted into the radiation equilibrium boundary condition in the viscous wall temperature boundary condition and the finite rate catalytic boundary condition in the viscous wall component boundary condition; these two temperature variation functions are used to simulate the wall catalytic reaction and radiation heat dissipation effect of the real heat-resistant material, thereby more realistically reflecting the chemical reaction process on the wall, which specifically includes the following sub-steps:

[0103] In step c, the two temperature variation function relationships in step b are substituted into the radiation equilibrium boundary condition in the viscous wall boundary condition and the finite rate catalytic boundary condition in the viscous wall component boundary condition; the calculation does not consider the internal structure heat conduction and material ablation reaction, and only considers the surface thermal radiation effect and catalytic effect. Then the wall energy conservation equation is:

[0104] ;

[0105] in, For gas components s The heat flow caused by the wall temperature gradient, is the total number of incoming gas component types, For gas components s Heat flow due to diffusion, is the wall radiation heat flux; where the components s The wall temperature gradient, heat flux caused by component diffusion, and radiation heat flux are:

[0106] ;

[0107] ;

[0108] ;

[0109] in, is the Boltzmann constant, is the thermal conductivity of the gas near the wall, n is the normal direction of the wall, is the total density of the incoming gas, For gas components s The equivalent diffusion coefficient, For gas components s The absolute enthalpy, For gas components s The quality score, is the incoming gas temperature;

[0110] Catalytic coefficient By affecting the catalytic reaction rate constant k w,s Indirectly affects component diffusion heat flow and catalytic reaction rate constant k w,s and catalytic coefficient c The relationship between them is:

[0111] ;

[0112] in, is the Boltzamnn constant, take , For gas components s molar mass;

[0113] Step d, flow field initialization, in the i =1 time step, preset number of inner loop steps j =0, the wall temperature is T w , and the actual heat flow is calculated from this Q and estimated heat flow Q es :

[0114] ;

[0115] ;

[0116] Among them, take ;

[0117] The actual heat flow Q and estimated heat flow Q es Convert to the corresponding value and , then the temperature change for:

[0118] ;

[0119] Then update the wall temperature preset value to , " "Indicates iterative update to determine whether or inner loop timesj If the set value is satisfied, exit the inner loop, otherwise j = j +1, and continue to execute the inner loop. is the minimum calculated residual;

[0120] Step e, the time step moves forward one step, that is, at the time step i = i +1 inside, execute the inner loop.

[0121] Example 6

[0122] Based on Example 5, in step e, the time-marching method uses the LU-SGS implicit method to advance the solution of the Navier-Stokes equations considering chemical reaction flow until the second norm of the full-field density between two adjacent time steps is less than the set value of two, and the flow field reaches a stable exit cycle, that is, the aircraft wall temperature and heat flux results are obtained.

[0123] The units involved in the embodiments of the present invention may be implemented in software or hardware, and the units described may also be provided in a processor. In some cases, the names of these units do not limit the units themselves.

[0124] According to one aspect of an embodiment of the present invention, a computer program product or computer program is provided, comprising computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the methods provided in the various optional implementations described above.

[0125] As another aspect, embodiments of the present invention further provide a computer-readable medium, which may be included in the electronic device described in the above embodiments, or may exist independently and not incorporated into the electronic device. The computer-readable medium carries one or more programs, and when executed by the electronic device, the electronic device implements the methods described in the above embodiments.

Claims

1. A wall boundary condition correction method that reflects the catalytic radiation temperature change effect of heat-proof materials, characterized in that: The following steps are involved: Based on the correlation data of the catalytic coefficient and radiation emissivity of different heat-resistant materials with the wall temperature, the temperature-varying function of the thermal radiation emissivity, material properties and wall temperature is obtained by fitting, and the temperature-varying function of the catalytic coefficient, material properties and wall temperature is obtained by fitting; These two temperature variation functions are then substituted into the radiation equilibrium boundary condition in the viscous wall temperature boundary condition, and the finite rate catalytic boundary condition in the viscous wall component boundary condition. These two temperature variation functions are used to simulate the wall catalytic reaction and radiation heat dissipation effect of real thermal insulation materials, thereby more realistically reflecting the chemical reaction process on the wall. The temperature variation function of thermal radiation emissivity, material properties and wall temperature is as follows: ； in, ε is the radiation emissivity, is the fitting coefficient, is the wall temperature; The temperature variation function of the catalytic coefficient, material properties and wall temperature is as follows: ； in, is the catalytic coefficient, is the fitting coefficient, is the wall temperature; The method of fitting the temperature-varying function of the thermal radiation emissivity, the material properties, and the wall temperature based on the correlation data of the catalytic coefficient and the radiation emissivity of different heat-resistant materials and the wall temperature, and fitting the temperature-varying function of the catalytic coefficient, the material properties, and the wall temperature, specifically includes the following sub-steps: Step a, obtaining experimentally determined data on the correlation between the catalytic coefficient and the radiation emissivity of the heat-shielding material and the wall temperature; Step b, using a three-parameter mathematical fitting method to convert the data obtained in step a into a corresponding temperature variation function form, including: The wall temperature of the heat protection material Convert to the corresponding dimensionless value , then the radiation emissivity in step a is ε and The temperature variation function is , M represents material, 、 、 is the fitting coefficient; then the radiation emissivity ε and The function is defined so that it satisfies ; Among them, when the wall temperature value is less than or equal to the minimum temperature value of the emissivity experiment When the radiation emissivity is taken as the minimum temperature value of the emissivity experiment Calculate the value of the temperature variation function of the independent variable , 、 、 is the fitting coefficient; when the wall temperature is greater than or equal to the maximum temperature value of the emissivity experiment When the radiation emissivity is taken as the maximum temperature value of the emissivity experiment Calculate the value of the temperature variation function of the independent variable , 、 、 is the fitting coefficient; when the wall temperature is at the minimum temperature of the emissivity experiment Maximum temperature value of emissivity experiment When the radiation emissivity is between Calculate the value of the temperature variation function of the independent variable , 、 、 is the fitting coefficient; The catalytic coefficient and The temperature variation function is ;in, 、 、 is the fitting coefficient.

2. The wall boundary condition correction method reflecting the catalytic radiation temperature change effect of heat-proof materials according to claim 1 is characterized in that: Substituting the two temperature variation functions into the radiation equilibrium boundary condition in the viscous wall temperature boundary condition and the finite rate catalytic boundary condition in the viscous wall component boundary condition, respectively; simulating the wall catalytic reaction and radiation heat dissipation effect of the real heat-resistant material by using these two temperature variation functions, thereby more realistically reflecting the chemical reaction process on the wall, specifically includes the following sub-steps: In step c, the two temperature variation function relationships in step b are substituted into the radiation equilibrium boundary condition in the viscous wall boundary condition and the finite rate catalytic boundary condition in the viscous wall component boundary condition; the calculation does not consider the internal structure heat conduction and material ablation reaction, and only considers the surface thermal radiation effect and catalytic effect. Then the wall energy conservation equation is: ； in, For gas components s The heat flow caused by the wall temperature gradient, is the total number of incoming gas component types, For gas components s Heat flow due to diffusion, is the wall radiation heat flux; where the components s The wall temperature gradient, heat flux caused by component diffusion, and radiation heat flux are: ； ； ； in, is the Boltzmann constant, is the thermal conductivity of the gas near the wall, n is the normal direction of the wall, is the total density of the incoming gas, For gas components s The equivalent diffusion coefficient, For gas components s The absolute enthalpy, For gas components s The quality score, is the incoming gas temperature; Catalytic coefficient By affecting the catalytic reaction rate constant k w,s Indirectly affects component diffusion heat flow and catalytic reaction rate constant k w,s and catalytic coefficient γ The relationship between them is: ； in, is the Boltzamnn constant, take , For gas components s molar mass; Step d, flow field initialization, in the i =1 time step, preset number of inner loop steps j =0, the wall temperature is T w , and the actual heat flow is calculated from this Q and estimated heat flow Q es : ； ； Among them, take ; The actual heat flow Q and estimated heat flow Q es Convert to the corresponding value and , then the temperature change for: ； Then update the wall temperature preset value to , " "Indicates iterative update to determine whether or inner loop times j If the set value is satisfied, exit the inner loop, otherwise j = j +1, and continue to execute the inner loop. is the minimum calculated residual; Step e, the time step moves forward one step, that is, at the time step i = i +1 inside, execute the inner loop.

3. The wall boundary condition correction method reflecting the catalytic radiation temperature change effect of heat-proof materials according to claim 2 is characterized in that: In step e, the time-marching method uses the LU-SGS implicit method to advance the solution of the Navier-Stokes equations considering chemical reaction flow until the second norm of the full-field density between two adjacent time steps is less than the set value of two, and the flow field reaches a stable exit cycle, that is, the aircraft wall temperature and heat flux results are obtained.

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