Method and system for calculating sweating and cooling mass flow rate of ablative material

Abstract

The embodiment of the invention provides an ablative material sweating cooling mass flow rate calculation method and system.The method comprises the steps that mesh generation is conducted on a calculation object, and sweating cooling mass flow rate is calculated according to input thermal boundary parameters, material / structure parameters, sweating working medium parameters and design constraints; constructing a coupling calculation model of thermal response of the ablative heat-proof material and porous medium seepage; the design constraint comprises the maximum ablation amount or the highest cold end wall surface temperature; on the basis of the initial sweating working medium flow rate, transient simulation is conducted through the coupling calculation model, thermal response parameters are obtained, and the thermal response parameters comprise a material solid phase temperature field, the surface ablation amount and the cold end wall surface temperature; and comparing the thermal response parameter with a design constraint, if a requirement is met, outputting the current sweating working medium flow rate, otherwise, adjusting the sweating working medium flow rate, recalculating to obtain the thermal response parameter, and comparing until the sweating cooling mass flow rate meeting the design constraint is obtained.

Description

TECHNICAL FIELD

[0001] The present document relates to the field of aircraft thermal protection technology, in particular to a sweating cooling mass flow rate calculation method and system for ablative materials. BACKGROUND

[0002] Thermal protection technology is a hot research topic in the field of aerodynamics, and lightweight, high efficiency and reliability are one of the important directions for the development of future aircraft thermal protection systems, which is also a great challenge that traditional thermal protection technology of aircraft must face. The current main thermal protection technology can be divided into three categories, namely passive thermal protection, semi-active thermal protection and active thermal protection. Different thermal protection methods have great differences in application objects, thermal protection performance, development cost, etc., and have formed a large number of rich research results in different research fields. Through the combination and cooperation of different advanced thermal protection technologies, higher thermal protection and thermal safety of aircraft in higher thermal flow and longer time can be realized.

[0003] At present, the sweating cooling technology is mainly applied to the thermal protection of liquid rocket engine combustion chamber, and the main advantages are no material and structure mass loss, reusability, etc.; and the ablation thermal protection technology is mainly used for the thermal protection of various aerospace vehicles in high thermal flow environment, and the main advantages are high thermal protection efficiency and strong adaptability to thermal environment changes. The application of sweating cooling technology to ablation thermal protection technology can further improve the adaptability of ablation thermal protection materials to special thermal environments with higher thermal flow and higher enthalpy, and greatly reduce the temperature and ablation rate, which is one of the important frontiers of future thermal protection technology. SUMMARY

[0004] The present application overcomes the shortcomings of the prior art and provides a rapid determination method for sweating cooling mass flow rate of ablative materials. The thermal response calculation model of ablative thermal protection materials and the porous medium seepage calculation model are coupled and analyzed. Through reasonable simplification and assumption of physical and chemical processes such as ablation, flow, phase change and heat transfer, efficient coupling calculation of ablation and sweating process is realized, and then the sweating cooling mass flow rate meeting the design ablation amount or temperature requirement is obtained through rapid iteration optimization based on the calculation method.

[0005] One or more embodiments of the present specification provide a sweating cooling mass flow rate calculation method for ablative materials, comprising: S1, meshing for a calculation object, and constructing a coupling calculation model of thermal response and porous medium seepage of ablative thermal protection materials by inputting thermal boundary parameters, material / structure parameters, sweating working medium parameters and design constraints; the design constraints include maximum ablation amount or highest cold end wall temperature; S2, based on the initial sweating working medium flow rate, transient simulation is performed through the coupling calculation model to obtain thermal response parameters, including material solid phase temperature field, surface ablation amount and cold end wall temperature; S3. Compare the thermal response parameters with the design constraints. If the requirements are met, output the current sweating working fluid flow rate. Otherwise, adjust the sweating working fluid flow rate and recalculate the thermal response parameters for comparison until a sweating cooling mass flow rate that meets the design constraints is obtained.

[0006] Furthermore, based on the initial sweating fluid flow rate, the transient simulation using the coupled calculation model specifically includes: Permeability is calculated based on the material's temperature field and microstructure parameters; Based on the phase state determination of the sweating working fluid, the fluid properties and linearization coefficients of the equation of state are determined. Based on the fluid property parameters and the working fluid vaporization rate, the internal fluid properties of the material are calculated to obtain the fluid pressure distribution; Calculate the boundary mass flux and internal mass flow rate based on the fluid pressure distribution; Using the boundary mass flux and internal mass flow rate, the aerothermal boundary conditions are updated and the heat exchange caused by fluid flow and phase change is calculated. Based on the updated boundary conditions and heat exchange terms, solve and update the solid-state temperature field and thermal response parameters of the material.

[0007] Furthermore, the calculation of permeability based on the material temperature field and microstructure parameters specifically involves: The transient heat transfer numerical simulation method of heat transfer is adopted. Based on the given mass flow rate of the sweating working fluid and combined with various input parameters, the internal temperature distribution, porosity and pyrolysis rate of the material at the current moment are solved. If there are decomposable components, the distribution of decomposable gas generation rate is calculated. Otherwise, the decomposable gas generation rate is set to zero. Using a gas-solid thermal equilibrium model, the material temperature distribution at the current moment is assigned to the sweating fluid to obtain the fluid temperature distribution assignment. Based on the fluid temperature distribution and porosity geometric parameter distribution, the permeability coefficient at different grid nodes is calculated.

[0008] Furthermore, the determination of fluid properties and linearization coefficients of the equation of state based on the phase state judgment of the sweating working fluid includes: Based on the homogeneity assumption, the properties of the active sweating working fluid are used to approximate the basic properties of the fluid within the material. According to the fluid temperature and pressure at the nodes, the property parameters of the fluid in the liquid or gas state are queried, including molecular weight, specific heat capacity, dynamic viscosity and density. The fluid state is determined based on the node fluid temperature, pressure, and saturated vapor pressure, and the linearization coefficient of the state equation is calculated based on the fluid state.

[0009] Furthermore, if the fluid pressure is greater than or equal to the saturated vapor pressure, it is determined to be in a liquid state, and the linearization coefficient of the fluid state equation is calculated based on the liquid state equation; otherwise, it is determined to be in a steam state or a vapor-liquid mixture state, and the linearization coefficient of the fluid state equation is calculated in combination with the vaporization rate of the sweating working fluid.

[0010] Furthermore, based on the fluid property parameters and the working fluid vaporization rate, the internal fluid properties of the material are calculated, and the fluid pressure distribution is obtained as follows: The fluid properties at different locations inside the material are calculated based on the fluid property parameters and the working fluid vaporization rate interpolation. The distribution of the cracked gas generation rate is used as the fluid mass source term. The fluid incompressibility assumption and the solid wall no slip assumption are adopted. The ideal gas equation of state and Darcy flow model after linearization coefficient correction are solved simultaneously to obtain the fluid pressure distribution.

[0011] Furthermore, when assessing the impact on the aerothermal boundary using boundary mass flux, the convective heat flux on the material surface is updated by introducing a thermal blockage factor.

[0012] This specification provides one or more embodiments of a system for calculating the mass flow rate of ablation material during sweating and cooling, including: Model building module: Used to mesh the computational object and construct a coupled computational model of the thermal response of the ablation heat-resistant material and the permeation of the porous medium by inputting thermal boundary parameters, material / structural parameters, sweating working fluid parameters and design constraints; the design constraints include the maximum ablation amount or the highest cold end wall temperature; Model simulation module: used to perform transient simulation based on the initial sweating working fluid flow rate through the coupled calculation model to obtain thermal response parameters, including the material solid phase temperature field, surface ablation amount and cold end wall temperature; Calculation module: Used to compare the thermal response parameters with the design constraints. If the requirements are met, the current sweating working fluid flow rate is output. Otherwise, the sweating working fluid flow rate is adjusted and the thermal response parameters are recalculated for comparison until the sweating cooling mass flow rate that meets the design constraints is obtained.

[0013] This specification provides one or more embodiments of an electronic device, including: Processor; and, A memory is configured to store computer-executable instructions, which, when executed, cause the processor to implement the steps of the above-described method for calculating the mass flow rate of the ablation material during sweating and cooling.

[0014] This specification provides one or more embodiments of a storage medium for storing computer-executable instructions that, when executed, implement the steps of the above-described method for calculating the mass flow rate of ablation material sweating and cooling.

[0015] The embodiments of this invention employ a coupled analysis using a thermal response calculation model for ablation-resistant heat protection materials and a permeation calculation model for porous media. By reasonably simplifying and assuming physicochemical processes such as ablation, flow, phase change, and heat transfer, efficient coupled calculation of ablation and sweating processes is achieved. Based on this calculation method, rapid iterative optimization is performed to obtain the sweating cooling mass flow rate that meets the design ablation amount or temperature requirements. This method features clear physical meaning, convenient engineering implementation, and high analysis efficiency, and can provide necessary data for the optimized design of aircraft thermal protection systems or thermal protection materials.

[0016] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in one or more embodiments of this specification or in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A flowchart illustrating a method for calculating the sweating cooling mass flow rate of an ablation material, provided for one or more embodiments of this specification; Figure 2 A flowchart illustrating a specific implementation method for calculating the mass flow rate of ablation material during sweating and cooling, provided in one or more embodiments of this specification. Figure 3 A schematic diagram of the composition of a sweating cooling mass flow rate calculation system for ablation materials provided in one or more embodiments of this specification; Figure 4 This is a schematic diagram of the structure of an electronic device provided for one or more embodiments of this specification. Detailed Implementation

[0019] To enable those skilled in the art to better understand the technical solutions in one or more embodiments of this specification, the technical solutions in one or more embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this specification, and not all of the embodiments. Based on one or more embodiments of this specification, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this document.

[0020] Method Implementation Examples According to an embodiment of the present invention, a method for calculating the mass flow rate of ablation material during sweating and cooling is provided. Figure 1 A flowchart illustrating a method for calculating the sweating cooling mass flow rate of an ablation material, provided for one or more embodiments of this specification. Figure 2 A flowchart illustrating a specific implementation method for calculating the sweating cooling mass flow rate of an ablation material, provided in one or more embodiments of this specification, is shown below. Figure 1 and Figure 2 As shown, the method for calculating the mass flow rate of ablation material sweating and cooling according to an embodiment of the present invention specifically includes: S1. Mesh the computational object and construct a coupled computational model of thermal response of ablation heat protection material and seepage of porous medium by inputting thermal boundary parameters, material / structure parameters, sweating working fluid parameters and design constraints; the design constraints include maximum ablation amount or highest cold end wall temperature.

[0021] S2. Based on the initial sweating working fluid flow rate, transient simulation is performed through the coupled calculation model to obtain thermal response parameters, which include the material solid phase temperature field, surface ablation amount, and cold end wall temperature.

[0022] In the transient simulation of the coupled computational model, the solid-phase temperature field of the material is first solved using a transient numerical method of heat transfer, based on the initially set mass flow rate of the sweating working fluid and in combination with material parameters and boundary conditions. This calculation simultaneously obtains the porosity distribution and pyrolysis rate distribution, which reflect changes in the material's microstructure. If a degradable component exists, the degradation gas generation rate distribution is calculated simultaneously for materials containing degradable resins; if this component is absent, the degradation gas generation rate is set to zero.

[0023] The typical expression of the material temperature distribution governing equation is: ; in, The density of the material; Specific heat capacity of the material; For temperature; For time; As a heat source; is the thermal conductivity.

[0024] Material internal porosity of each grid node The typical calculation method is as follows: ; in, The porosity of the material before carbonization. The porosity of the material after carbonization. The pyrolysis rate is given.

[0025] The typical method for calculating the internal pyrolysis gas generation rate of a material is as follows: ; in, For changes in node density, Calculate the time step.

[0026] Subsequently, using a gas-solid thermal equilibrium model, the calculated material temperature field is directly applied to the sweating fluid to establish the fluid temperature distribution. Based on this fluid temperature field and the dynamically changing porosity geometric parameter distribution of the material, classical empirical formulas such as the Kzeny-Kármán formula are used to calculate the permeability coefficient of each grid node, quantifying the conductivity of the porous medium for fluid flow. ; Where c is a constant related to the object (generally taken as 4.8±0.3 for spherical particle beds). Fiber / particle diameter Porosity.

[0027] In the fluid property determination stage, homogenization is employed, using the properties of the actively injected sweating working fluid to represent the basic characteristics of the fluid within the material. By querying the working fluid property database, key parameters such as molecular weight, specific heat capacity, dynamic viscosity, and density at different temperatures and pressures are obtained for each node, enabling working fluid phase determination: by comparing the node fluid pressure with the saturated vapor pressure corresponding to the current temperature, it is determined whether it is in a liquid, gas, or mixed state. Specifically, if the fluid pressure is greater than or equal to the saturated vapor pressure, it is determined to be in a liquid state, and based on compressibility correction, the linearization coefficient of the fluid state equation is calculated according to the liquid state equation; otherwise, it is determined to be in a vapor state or a vapor-liquid mixture state, combined with the vaporization rate of the sweating working fluid. Calculate the linearization coefficients of the fluid state equation .

[0028] Taking water as an example under normal temperature and pressure, the linearization coefficient of the fluid state equation in the steam state... The value is 1, which is the linearization coefficient of the fluid state equation in the liquid state. The typical conversion method is as follows:

[0029] in, The pressure of liquid water; The molecular weight of water; The density of water; This is the universal gas constant; The temperature of the water.

[0030] Based on this, by integrating fluid property parameters and working fluid vaporization rate, an interpolation method is used to accurately describe the fluid state properties at various locations within the material. Using the distribution of pyrolysis gas generation rate as the fluid mass source term, and considering the assumptions of fluid incompressibility and no-slip on the solid wall, the ideal gas law and Darcy flow model, corrected for linearization coefficients, are solved simultaneously to obtain the transient fluid pressure distribution within the material. A typical expression of the governing equations for fluid nodal pressure distribution obtained from the ideal gas law and Darcy flow model is as follows: ; in, , The area is the unit area, in m2; S represents the fluid velocity, in m / s; S represents the element side length, in m. Internal gas source, unit: kg / s; , representing quantities related to the current state of the gas within the unit, in units of kg·m / Pa / s. and This represents the summation of the edges of the fluid mesh nodes.

[0031] Linearization coefficients of the equation The typical expression for the corrected calculation parameters is: .

[0032] Based on the fluid pressure distribution obtained from the solution Further calculation of the boundary mass flux of the heated surface. Or boundary pressure, based on fluid pressure distribution Calculate the internal mass flow rate of each grid boundary. Boundary fluid mass flux Mass flow rate of fluid at the boundaries of each grid point The typical calculation method is as follows: ; in, , which is a quantity related to the current state of the gas within the cell; This refers to the pressure gradient at the interface or the boundary of nodes within the material.

[0033] For material walls with aerodynamic heating, the boundary fluid mass flux ablation jet flow rate of ablation heat protection materials Summing is performed to determine the total gas ejection flow rate at the material-aerodynamic interface. This evaluates the coupling effect of interfacial fluid ejection on the aerodynamic boundary and updates the convective heat flux at the material-aerodynamic interface. Fluid mass flow rate using grid point boundaries The heat exchange between nodes caused by fluid flow and phase change is statistically analyzed and used as the heat source or heat sink term in the solution of the material temperature field. .

[0034] A typical calculation method for the coupling effect of interfacial fluid ejection on aerodynamic thermal boundaries is as follows: Define thermal blocking factor for: ; in, , These represent the aerodynamic heating convective heat fluxes with and without considering the effects of gas ejection.

[0035] Thermal blocking factor The typical calculation formula is: ; in, This is an empirical coefficient; The mass flow rate of the dimensionless ejected gas.

[0036] Finally, based on the obtained material temperature field heat source or heat sink term and the convective heat flux of the updated aerodynamic thermal interface By combining the material's thermal property parameters, the solid-phase temperature field control equation is solved and the relevant thermal response parameters such as the material's solid-phase temperature field, surface ablation rate, cold-end wall temperature, internal material temperature, cold-end sweating working fluid pressure, and hot-end ejector mass flow rate are updated.

[0037] S3. Compare the thermal response parameters with the design constraints. If the requirements are met, output the current sweating working fluid flow rate. Otherwise, adjust the sweating working fluid flow rate and recalculate the thermal response parameters for comparison until a sweating cooling mass flow rate that meets the design constraints is obtained.

[0038] The process examines whether key thermal response parameters such as ablation rate and temperature meet design constraints. If the calculated results of all key thermal response parameters meet or exceed the design constraints, the currently used sweating working fluid flow rate is determined to be a feasible solution, the process terminates, and the flow rate value is output as the final design recommendation. If the comparison results do not meet the requirements, such as excessive ablation rate or cold wall surface temperature exceeding the limit, the flow rate optimization and adjustment mechanism is activated. Based on the direction and degree of deviation of the calculation results, the sweating working fluid flow rate is systematically adjusted according to a preset optimization strategy. This adjustment can be manually set based on engineering experience, or a new and more reasonable trial flow rate value can be automatically generated using an efficient numerical optimization algorithm. Subsequently, the adjusted new working fluid flow rate is used as input conditions to re-drive the aforementioned complete coupled calculation process for a new round of transient simulation, thereby obtaining the thermal response parameters corresponding to the new flow rate. The process is automatically iterated until a critical or optimal sweating cooling mass flow rate that can simultaneously meet all design constraints is found.

[0039] The beneficial effects of this invention are as follows: The embodiments of this invention employ a coupled analysis using a thermal response calculation model for ablation-resistant heat protection materials and a permeation calculation model for porous media. By reasonably simplifying and assuming physicochemical processes such as ablation, flow, phase change, and heat transfer, efficient coupled calculation of ablation and sweating processes is achieved. Based on this calculation method, rapid iterative optimization is performed to obtain the sweating cooling mass flow rate that meets the design ablation amount or temperature requirements. This method features clear physical meaning, convenient engineering implementation, and high analysis efficiency, and can provide necessary data for the optimized design of aircraft thermal protection systems or thermal protection materials.

[0040] System Implementation Examples According to embodiments of the present invention, a system for calculating the mass flow rate of ablation material during sweating and cooling is provided. Figure 3 A schematic diagram illustrating the composition of a sweating cooling mass flow rate calculation system for ablation materials, provided for one or more embodiments of this specification, is shown below. Figure 3 As shown, the ablation material sweating cooling mass flow rate calculation system according to an embodiment of the present invention specifically includes: Model building module 30: Used to mesh the computational object and construct a coupled computational model of the thermal response of the ablation heat-resistant material and the seepage of the porous medium by inputting thermal boundary parameters, material / structure parameters, sweating working fluid parameters and design constraints; the design constraints include the maximum ablation amount or the highest cold end wall temperature; Model simulation module 32: used to perform transient simulation based on the initial sweating working fluid flow rate through the coupled calculation model to obtain thermal response parameters, including the material solid phase temperature field, surface ablation amount and cold end wall temperature; Calculation module 34: Used to compare the thermal response parameters with the design constraints. If the requirements are met, the current sweating working fluid flow rate is output. Otherwise, the sweating working fluid flow rate is adjusted and the thermal response parameters are recalculated for comparison until the sweating cooling mass flow rate that meets the design constraints is obtained.

[0041] The embodiments of the present invention are system embodiments corresponding to the above method embodiments. The specific operation of each module can be understood by referring to the description of the method embodiments, and will not be repeated here.

[0042] Device Example 1 This invention provides an electronic device, such as... Figure 4 As shown, it includes: a memory 40, a processor 42, and a computer program stored in the memory 40 and executable on the processor 42. When the computer program is executed by the processor 42, it performs the following method steps: S1. Mesh the computational object and construct a coupled computational model of the thermal response of the ablation heat-resistant material and the permeation of the porous medium by inputting thermal boundary parameters, material / structure parameters, sweating working fluid parameters and design constraints; the design constraints include the maximum ablation amount or the highest cold end wall temperature. S2. Based on the initial sweating working fluid flow rate, transient simulation is performed through the coupled calculation model to obtain thermal response parameters, including the material solid phase temperature field, surface ablation amount and cold end wall temperature. S3. Compare the thermal response parameters with the design constraints. If the requirements are met, output the current sweating working fluid flow rate. Otherwise, adjust the sweating working fluid flow rate and recalculate the thermal response parameters for comparison until a sweating cooling mass flow rate that meets the design constraints is obtained.

[0043] Device Example 2 This invention provides a computer-readable storage medium storing an information transmission implementation program. When executed by a processor 42, the program performs the following method steps: S1. Mesh the computational object and construct a coupled computational model of the thermal response of the ablation heat-resistant material and the permeation of the porous medium by inputting thermal boundary parameters, material / structure parameters, sweating working fluid parameters and design constraints; the design constraints include the maximum ablation amount or the highest cold end wall temperature. S2. Based on the initial sweating working fluid flow rate, transient simulation is performed through the coupled calculation model to obtain thermal response parameters, including the material solid phase temperature field, surface ablation amount and cold end wall temperature. S3. Compare the thermal response parameters with the design constraints. If the requirements are met, output the current sweating working fluid flow rate. Otherwise, adjust the sweating working fluid flow rate and recalculate the thermal response parameters for comparison until a sweating cooling mass flow rate that meets the design constraints is obtained.

[0044] The computer-readable storage media described in this embodiment include, but are not limited to, ROM, RAM, disk, or optical disk.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calculating the mass flow rate of ablation material during sweating and cooling, characterized in that, include: S1. Mesh the computational object and construct a coupled computational model of the thermal response of the ablation heat-resistant material and the permeation of the porous medium by inputting thermal boundary parameters, material / structure parameters, sweating working fluid parameters and design constraints; the design constraints include the maximum ablation amount or the highest cold end wall temperature. S2. Based on the initial sweating working fluid flow rate, transient simulation is performed through the coupled calculation model to obtain thermal response parameters, including the material solid phase temperature field, surface ablation amount and cold end wall temperature. S3. Compare the thermal response parameters with the design constraints. If the requirements are met, output the current sweating working fluid flow rate. Otherwise, adjust the sweating working fluid flow rate and recalculate the thermal response parameters for comparison until a sweating cooling mass flow rate that meets the design constraints is obtained.

2. The method according to claim 1, characterized in that, Based on the initial sweating fluid flow rate, the transient simulation using the coupled calculation model specifically includes: Permeability is calculated based on the material's temperature field and microstructure parameters; Based on the phase state determination of the sweating working fluid, the fluid properties and linearization coefficients of the equation of state are determined. Based on the fluid property parameters and the working fluid vaporization rate, the internal fluid properties of the material are calculated to obtain the fluid pressure distribution; Calculate the boundary mass flux and internal mass flow rate based on the fluid pressure distribution; Using the boundary mass flux and internal mass flow rate, the aerothermal boundary conditions are updated and the heat exchange caused by fluid flow and phase change is calculated. Based on the updated boundary conditions and heat exchange terms, solve and update the solid-state temperature field and thermal response parameters of the material.

3. The method according to claim 2, characterized in that, The calculation of permeability based on the material's temperature field and microstructure parameters is specifically as follows: The transient heat transfer numerical simulation method of heat transfer is adopted. Based on the given mass flow rate of the sweating working fluid and combined with various input parameters, the internal temperature distribution, porosity and pyrolysis rate of the material at the current moment are solved. If there are decomposable components, the distribution of decomposable gas generation rate is calculated. Otherwise, the decomposable gas generation rate is set to zero. Using a gas-solid thermal equilibrium model, the material temperature distribution at the current moment is assigned to the sweating fluid to obtain the fluid temperature distribution assignment. Based on the fluid temperature distribution and porosity geometric parameter distribution, the permeability coefficient at different grid nodes is calculated.

4. The method according to claim 2, characterized in that, The determination of fluid properties and linearization coefficients of the equation of state based on the phase state judgment of the sweating working fluid includes: Based on the homogeneity assumption, the properties of the active sweating working fluid are used to approximate the basic properties of the fluid within the material. According to the fluid temperature and pressure at the nodes, the property parameters of the fluid in the liquid or gas state are queried, including molecular weight, specific heat capacity, dynamic viscosity and density. The fluid state is determined based on the node fluid temperature, pressure, and saturated vapor pressure, and the linearization coefficient of the state equation is calculated based on the fluid state.

5. The method according to claim 4, characterized in that, If the fluid pressure is greater than or equal to the saturated vapor pressure, it is determined to be in the liquid state, and the linearization coefficient of the fluid state equation is calculated according to the liquid state equation. Otherwise, it is determined to be in a steam state or a vapor-liquid mixture state, and the linearization coefficient of the fluid state equation is calculated in combination with the vaporization rate of the sweating working fluid.

6. The method according to claim 2, characterized in that, Based on the fluid property parameters and the vaporization rate of the working fluid, the internal fluid properties of the material are calculated, and the fluid pressure distribution is obtained as follows: The fluid properties at different locations inside the material are calculated based on the fluid property parameters and the working fluid vaporization rate interpolation. The distribution of the cracked gas generation rate is used as the fluid mass source term. The fluid incompressibility assumption and the solid wall no slip assumption are adopted. The ideal gas equation of state and Darcy flow model after linearization coefficient correction are solved simultaneously to obtain the fluid pressure distribution.

7. The method according to claim 2, characterized in that, When assessing the impact on aerodynamic thermal boundaries using boundary mass flux, a thermal blockage factor is introduced to update the convective heat flux on the material surface.

8. A system for calculating the mass flow rate of ablation material during sweating and cooling, characterized in that, include: Model building module: Used to mesh the computational object and construct a coupled computational model of the thermal response of the ablation heat-resistant material and the permeation of the porous medium by inputting thermal boundary parameters, material / structural parameters, sweating working fluid parameters and design constraints; the design constraints include the maximum ablation amount or the highest cold end wall temperature; Model simulation module: used to perform transient simulation based on the initial sweating working fluid flow rate through the coupled calculation model to obtain thermal response parameters, including the material solid phase temperature field, surface ablation amount and cold end wall temperature; Calculation module: Used to compare the thermal response parameters with the design constraints. If the requirements are met, the current sweating working fluid flow rate is output. Otherwise, the sweating working fluid flow rate is adjusted and the thermal response parameters are recalculated for comparison until the sweating cooling mass flow rate that meets the design constraints is obtained.

9. An electronic device, characterized in that, include: processor; as well as, A memory configured to store computer-executable instructions, which, when executed, cause the processor to implement the steps of the method for calculating the mass flow rate of ablation material sweating cooling as described in any one of claims 1 to 7.

10. A storage medium, characterized in that, Used to store computer-executable instructions, which, when executed, implement the steps of the method for calculating the mass flow rate of ablation material sweating and cooling as described in any one of claims 1 to 7.

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