Aircraft thermal protection structure design method and device and medium

Abstract

The embodiment of the invention provides an aircraft thermal protection design method and device and a medium. The method comprises the steps that aerodynamic heat calculation is conducted according to the flight working condition of an aircraft to obtain aerodynamic heat data; determining a protective material of each part of the thermal protection structure of the aircraft according to the aerodynamic heat data, and determining physical property parameters corresponding to the protective material of each part of the thermal protection structure; according to the aerodynamic heat data and the physical property parameters corresponding to the protective material of each part of the thermal protection structure, and according to the principles of thermal convection, thermal radiation and thermal conduction, analyzing the thermal protection structure to determine the relationship of the temperature of the thermal protection structure changing with time; and comparing the relationship of the temperature changing along with the time with a preset thermal protection design requirement, and if the relationship of the temperature changing along with the time meets the preset thermal protection design requirement, outputting the relationship of the temperature changing along with the time, the protection material of each part of the thermal protection structure and the corresponding physical property parameters.

Description

Technical Field

[0001] This invention relates to the field of aircraft thermal protection, and more particularly to a design method, device and medium for aircraft thermal protection structures. Background Technology

[0002] A rapid design and optimization method for integrated thermal protection structures of aircraft is proposed, based on theoretical calculations of one-dimensional transient heat conduction under the conditions of temperature and adiabatic boundaries. The design and topology optimization of thermal insulation structures containing phase change materials (PCMs) present an integrated thermal protection design scheme, and its effectiveness is verified through transient heat transfer analysis. One existing method involves optimizing the macroscopic temperature field of the leading edge component using a three-dimensional orthogonal woven ceramic matrix composite material and co-designing the mesoscopic woven structure to reduce the temperature of the leading edge component, effectively lowering the leading edge temperature without additional cooling measures. This method of optimizing thermal protection performance using macroscopic temperature field optimization and co-designing the mesoscopic woven structure is suitable for the integrated design of temperature field and thermally conductive material structures. However, most thermal protection schemes consider mature materials, and such schemes significantly increase manufacturing costs from design to production and even testing. Another existing method designs a diamond-shaped forced transition zone at the leading edge of the rudder shaft based on the heat flux value at the stagnation point of the entire trajectory of the aircraft for active cooling design. Current rapid design and optimization methods for integrated thermal protection structures oversimplify boundary conditions and only consider single-layer thermal protection structures, which differs significantly from actual design solutions. The design and topology optimization of thermal insulation structures containing phase change materials utilizes ANSYS software for thermal protection effect analysis, which is costly for complex materials. The primary focus is on designing a diamond-shaped forced transition zone at the leading edge of the rudder shaft based on the heat flux values ​​at the stagnation points throughout the aircraft's trajectory; this approach does not consider the internal thermal protection structure design.

[0003] In the process of developing this invention, the applicant discovered at least the following problems in the prior art:

[0004] It only considered the design of a single-layer thermal protection structure and the high cost of materials for complex models. Summary of the Invention

[0005] This invention provides a design method, apparatus, and medium for aircraft thermal protection structures, which solves the problems of designing only single-layer thermal protection structures and the high cost of materials for complex models.

[0006] To achieve the above objectives, in a first aspect, embodiments of the present invention provide a method for designing a thermal protection structure for an aircraft, comprising:

[0007] Aerodynamic and thermal data are obtained by performing aerodynamic and thermal calculations based on the flight conditions of the aircraft.

[0008] Based on aerodynamic thermal data, the protective materials of each part of the aircraft's thermal protection structure are determined, and the corresponding physical property parameters of the protective materials of each part of the thermal protection structure are obtained.

[0009] Based on aerodynamic thermal data and the physical properties of the protective materials of each part of the thermal protection structure, and based on the principles of thermal convection, thermal radiation and thermal conduction, the thermal protection structure is analyzed to determine the relationship between the temperature of the thermal protection structure and time.

[0010] The relationship between temperature and time is compared with the preset thermal protection design requirements. If the relationship between temperature and time meets the preset thermal protection design requirements, the relationship between temperature and time, the protective materials of each part of the thermal protection structure, and the corresponding physical property parameters are output.

[0011] Furthermore, the design methods for aircraft thermal protection structures also include:

[0012] If the temperature-time relationship does not meet the design requirements, the process returns to the step of determining the protective materials for each part of the aircraft's thermal protection structure based on aerodynamic thermal data, in order to re-specify the protective materials, and continues to the next step after determining the protective materials for each part of the aircraft's thermal protection structure based on aerodynamic thermal data and obtaining the corresponding physical property parameters of the protective materials for each part of the thermal protection structure.

[0013] Furthermore, the aircraft's thermal protection structure includes: an external heat insulation layer, an internal heat insulation layer, and a cavity layer between the external heat insulation layer and the internal heat insulation layer;

[0014] Based on aerodynamic thermal data and the physical properties of the protective materials in each part of the thermal protection structure, and according to the principles of thermal convection, thermal radiation, and thermal conduction, the relationship between the temperature of the thermal protection structure and time is analyzed and determined, including:

[0015] Based on the physical properties and aerodynamic thermal data of the protective materials of the external insulation layer, internal insulation layer, and cavity layer, thermal convection, thermal radiation, and thermal conduction analyses are performed on the external insulation layer, cavity layer, and internal insulation layer to determine the relationship between the temperature of the thermal protection structure and time.

[0016] Furthermore, based on the physical properties and aerodynamic-thermal data of the protective materials of the external insulation layer, internal insulation layer, and cavity layer, thermal convection, thermal radiation, and thermal conduction analyses are performed on the external insulation layer, cavity layer, and internal insulation layer to determine the relationship between the temperature of the thermal protection structure and time, including:

[0017] Based on aerodynamic thermal data and the physical property parameters of the protective material of the external insulation layer, thermal convection and thermal radiation analysis were performed on the outer surface of the external insulation layer. The radiative heat transfer and convective heat transfer between the outer surface of the external insulation layer and the external environment were determined as the radiative heat transfer between the outer wall and the environment and the convective heat transfer between the outer wall and the environment.

[0018] The thermal conductivity of the external insulation layer is obtained by performing thermal conductivity analysis based on aerodynamic thermal data, radiative heat transfer between the outer wall and the environment, convective heat transfer between the outer wall and the environment, and the physical property parameters of the protective material of the external insulation layer.

[0019] Based on the thermal conductivity of the external insulation layer and the physical property parameters of the protective material of the cavity layer, the thermal conduction and thermal radiation of the cavity layer are analyzed to obtain the thermal conductivity and thermal radiation of the cavity layer.

[0020] Based on the thermal conductivity of the cavity layer, the radiative heat of the cavity layer, and the physical property parameters of the protective material of the internal insulation layer, the thermal conductivity of the internal insulation layer is analyzed.

[0021] Based on the thermal conductivity and protective material of the internal insulation layer, thermal convection and thermal radiation analysis of the internal insulation layer and the interior of the aircraft cabin are conducted to obtain the convective heat transfer between the internal insulation layer and the cabin and the radiative heat of the internal insulation layer.

[0022] Transient analysis was conducted based on aerodynamic thermal data, radiative heat transfer between the outer wall and the environment, thermal conduction of the external insulation layer, thermal conduction of the cavity layer, radiative heat of the cavity layer, thermal conduction of the internal insulation layer, convective heat transfer between the internal insulation layer and the cabin, and radiative heat of the internal insulation layer to obtain the relationship between the temperature of the aircraft's thermal protection structure and time.

[0023] Furthermore, the design method for the thermal protection structure of an aircraft also includes: physical properties including any one or more of thermal conductivity, density, specific heat capacity, and emissivity.

[0024] Secondly, embodiments of the present invention provide a design device for a thermal protection structure of an aircraft, comprising:

[0025] The aerodynamic thermal data determination unit is used to perform aerodynamic thermal calculations based on the flight conditions of the aircraft to obtain aerodynamic thermal data.

[0026] The protective material determination unit is used to determine the protective materials of each part of the thermal protection structure of the aircraft based on aerodynamic thermal data, and to obtain the physical property parameters corresponding to the protective materials of each part of the thermal protection structure.

[0027] The temperature-time relationship determination unit is used to analyze and determine the temperature-time relationship of the thermal protection structure based on aerodynamic thermal data and the physical property parameters of the protective materials of each part of the thermal protection structure, and based on the principles of thermal convection, thermal radiation and thermal conduction.

[0028] The design result output unit is used to compare the relationship between temperature and time with the preset design requirements. If the relationship between temperature and time meets the design requirements, it outputs the relationship between temperature and time, the protective materials of each part of the thermal protection structure, and the corresponding physical property parameters.

[0029] Furthermore, the aircraft thermal protection structure design device also includes:

[0030] The redesign unit is used to re-trigger the protective material determination unit if the temperature-time relationship does not meet the design requirements, and to continue triggering the physical property parameter determination unit, the temperature-time relationship determination unit, and the design result output unit.

[0031] Furthermore, the thermal protection structure includes: an external thermal insulation layer, an internal thermal insulation layer, and a cavity layer between the external thermal insulation layer and the internal thermal insulation layer;

[0032] The temperature-time relationship determination unit is specifically used to: perform thermal convection, thermal radiation, and thermal conduction analysis on the external insulation layer, the internal insulation layer, and the cavity layer based on the physical property parameters and aerodynamic thermal data of their respective protective materials, and determine the temperature change relationship of the thermal protection structure over time.

[0033] Furthermore, the temperature-time relationship determination unit includes:

[0034] The outer wall radiative heat determination module is used to perform thermal convection and thermal radiation analysis on the outer surface of the outer insulation layer based on aerodynamic thermal data and the physical property parameters corresponding to the protective material of the outer insulation layer, and to determine the radiative heat transfer and convective heat transfer between the outer surface of the outer insulation layer and the external environment as the corresponding radiative heat transfer and convective heat transfer between the outer wall and the environment.

[0035] The outer wall thermal conductivity determination module is used to perform thermal conduction analysis on the outer insulation layer based on aerodynamic thermal data, radiative heat transfer between the outer wall and the environment, convective heat transfer between the outer wall and the environment, and the physical property parameters of the protective material of the outer insulation layer to obtain the thermal conductivity of the outer insulation layer.

[0036] The cavity radiation thermal conductivity determination module is used to perform thermal conduction and thermal radiation analysis on the cavity layer based on the thermal conductivity of the external insulation layer and the physical property parameters of the protective material of the cavity layer to obtain the cavity layer thermal conductivity and cavity layer radiation thermal conductivity.

[0037] The internal insulation layer thermal conductivity determination module is used to perform thermal conduction analysis on the internal insulation layer based on the thermal conductivity of the cavity layer, the radiative heat of the cavity layer, and the physical property parameters of the protective material of the internal insulation layer, so as to obtain the thermal conductivity of the internal insulation layer.

[0038] The module for determining the convection and radiation heat between the internal insulation layer and the cabin is used to perform thermal convection and thermal radiation analysis on the internal insulation layer and the cabin interior of the aircraft based on the thermal conductivity of the internal insulation layer and the protective material of the internal insulation layer to obtain the convective heat transfer between the internal insulation layer and the cabin and the radiation heat of the internal insulation layer.

[0039] The temperature-time relationship determination module is used to perform transient analysis based on aerodynamic thermal data, radiative heat transfer between the outer wall and the environment, thermal conduction of the external insulation layer, thermal conduction of the cavity layer, radiative heat of the cavity layer, thermal conduction of the internal insulation layer, convective heat transfer between the internal insulation layer and the cabin, and radiative heat of the internal insulation layer to obtain the relationship between the temperature of the aircraft's thermal protection structure and time.

[0040] Thirdly, embodiments of the present invention provide a readable storage medium storing program code for implementing the aircraft thermal protection structure design method as described in any of the first aspects.

[0041] The above technical solution offers the following advantages: By comprehensively considering the characteristics of aerodynamics, thermal protection structure, and cabin environment, the design of the thermal protection structure is more accurate. Employing engineering algorithms allows for convenient, rapid, and efficient design of the thermal protection structure, significantly saving manpower, material resources, and financial costs. It comprehensively considers the cabin and flight environment, enabling multi-layered thermal protection design. Furthermore, it comprehensively considers aerodynamics in the flight environment, radiation from the multi-layered thermal protection materials, internal heat conduction, and convective heat transfer within the cabin. Moreover, the use of transient theoretical calculation models allows for the rapid and convenient design and optimization of complex thermal protection structures. Through programmed and rapid calculations, it achieves the effect of rapid iterative optimization of the solution. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of the present invention or 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 of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a flowchart of a method for designing a thermal protection structure for an aircraft, one of the embodiments of the present invention;

[0044] Figure 2 This is a schematic diagram of the architecture of an aircraft thermal protection structure design device, one of the embodiments of the present invention;

[0045] Figure 3 This is a schematic diagram of a heat protection structure and heat transfer in one embodiment of the present invention;

[0046] The reference numerals in the attached figures are as follows:

[0047] Q1. Aerodynamic heat transfer; Q2. Radiative heat transfer between the outer wall and the environment, and convective heat transfer between the outer wall and the environment; Q3. Thermal conduction of the external insulation layer; Q4. Thermal conduction and radiative heat transfer of the cavity layer; Q5. Thermal conduction of the internal insulation layer; Q6. Convective heat transfer between the internal insulation layer and the cabin; Q7. Radiative heat transfer of the internal insulation layer; 31. Outer wall of the external insulation layer; 32. Inner wall of the external insulation layer; 33. Outer wall of the internal insulation layer; 34. Inner wall of the internal insulation layer; 301. External insulation layer; 302. Cavity layer; 303. Internal insulation layer. Detailed Implementation

[0048] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] Technical terms:

[0050] Thermal radiation: Electromagnetic radiation produced due to heat.

[0051] Thermal conduction: The process by which energy is transferred from a hotter part of an object to a colder part due to the collisions of a large number of molecules, atoms or electrons.

[0052] Thermal convection: The process of heat exchange between a fluid and a solid when the fluid flows over the surface of the solid.

[0053] Thermal protection: The basic purpose of thermal protection is to ensure the safety of the aircraft and to keep the internal payload or instruments and equipment within the permissible temperature and pressure range.

[0054] Thermal conductivity: Under steady-state heat transfer conditions, for a 1m thick material with a temperature difference of 1℃ between its two surfaces, how much heat is transferred through the 1m thick material in a given time? 2 Heat transferred by area.

[0055] Emissivity: The ratio of the radiant flux emitted per unit area of ​​an object's surface to the radiant flux emitted by a blackbody at the same temperature.

[0056] Convective heat transfer coefficient: The heat transfer capacity between a fluid and a solid surface.

[0057] The inventors discovered that existing technologies mainly focus on one aspect of aerodynamics or thermal protection, designing the two directions separately. This can easily lead to redundant margins and over-protection, and lacks an integrated design method that considers the overall flight environment, thermal protection design, and cabin environment.

[0058] The inventors discovered that when an aircraft passes through the atmosphere during flight, its surface experiences aerodynamic heating, causing both surface and internal temperatures to rise. Excessive temperatures can malfunction the aircraft's instruments and equipment. The key to solving the "thermal barrier" problem is the rational design of a thermal protection system to ensure the aircraft's normal operation. The goal of aircraft thermal protection is to ensure that the internal structure of the aircraft remains within a safe temperature range; its design specification is that the internal temperature of the structure does not exceed the allowable temperature. The purpose of thermal protection heat transfer design calculations is twofold: 1. To calculate and analyze the transient temperatures of each internal structure; 2. To calculate the internal temperature of the thermal protection structure in order to evaluate its performance.

[0059] Through theoretical research and reasonable assumptions, the inventors established the physical and mathematical models corresponding to the implementation of this invention, and realized the thermal protection design of the aircraft based on the obtained models.

[0060] To achieve the above objectives, firstly, such as Figure 1 As shown, an embodiment of the present invention provides a thermal protection design method for an aircraft, comprising:

[0061] Step S10: Perform aerodynamic and thermal calculations based on the flight conditions of the aircraft to obtain aerodynamic and thermal data;

[0062] Step S11: Determine the protective materials of each part of the thermal protection structure of the aircraft based on aerodynamic thermal data, and obtain the physical property parameters corresponding to the protective materials of each part of the thermal protection structure.

[0063] Step S12: Based on the aerodynamic thermal data and the physical property parameters of the protective materials of each part of the thermal protection structure, and based on the principles of thermal convection, thermal radiation and thermal conduction, analyze the thermal protection structure and determine the relationship between the temperature of the thermal protection structure and time.

[0064] Step S13: Compare the relationship between temperature and time with the preset thermal protection design requirements. If the relationship between temperature and time meets the preset thermal protection design requirements, output the relationship between temperature and time, the protective materials of each part of the thermal protection structure, and the corresponding physical property parameters.

[0065] In some embodiments, flight conditions include, but are not limited to: flight altitude, atmospheric pressure, atmospheric temperature, atmospheric density and / or aircraft speed; aerodynamic thermal data include, but are not limited to: aerodynamic thermal data such as cold wall heat flux, wall temperature, pressure distribution, velocity distribution and / or temperature distribution.

[0066] like Figure 3 As shown, aerodynamic and thermal calculations were performed on the exterior of the external thermal insulation layer 301 under the flight conditions of the aircraft to obtain aerodynamic and thermal data (i.e., Figure 3 (Q1 in the original text); Based on aerodynamic thermal data, the required operating temperature range for thermal protection materials can be determined, thereby determining the necessary physical properties of the materials. These physical properties include any one or more of thermal conductivity, density, specific heat capacity, and emissivity. These physical properties are inherent to each type of protective material and characterize its properties. Once a protective material is selected or determined based on aerodynamic thermal data, its corresponding physical properties are also determined.

[0067] Furthermore, based on aerodynamic thermal data, the required operating temperature range of the protective material can be determined, thereby selecting the appropriate type of protective material based on the corresponding operating temperature range, and subsequently determining the physical property parameters of the selected protective material.

[0068] The thermal protection structure of an aircraft may consist of one or more parts, and the protective material for each part needs to be determined. Once the protective material is determined, the corresponding thermal property parameters for each part can be obtained by searching conventional material thermal property data, or the parameters can be determined empirically. The thermal property data for the protective material can be in the form of documents or data sheets, such as using Excel to record the properties of metallic and non-metallic protective materials. Types of protective materials include gold, silver, copper, iron, aluminum, fiberglass, carbon fiber, asphalt, and paper honeycomb, among others. The properties include any one or more of the following: thermal conductivity, density, specific heat capacity, and emissivity.

[0069] Based on aerodynamic thermal data and the physical properties of the protective materials in each part of the thermal protection structure, and according to the principles of thermal convection, thermal radiation, and thermal conduction, the thermal protection structure is analyzed to determine its temperature-time relationship. This relationship is then compared with the preset thermal protection design requirements. If the temperature-time relationship meets the design requirements, the output includes the temperature-time relationship, the protective materials in each part of the thermal protection structure, and their corresponding physical properties. The preset thermal protection design requirements are predefined design parameters that the thermal protection structure must meet before designing the structure, including but not limited to the preset temperature-time relationship. The thermal protection structure can be pre-established through theoretical research, combined with reasonable assumptions, to establish corresponding physical and mathematical models.

[0070] The embodiments of this invention have the following technical effects: The coupled and integrated design of aerodynamics and thermal protection more closely approximates the actual physical process, resulting in higher design accuracy. Combining aerodynamics and thermal protection structure analysis and design solves the problem of redundant margins and over-protection caused by analyzing either aspect separately. Furthermore, aerodynamic data is obtained through aerodynamic calculations based on flight conditions. Considering not only the thermal protection structure and the cabin environment but also the influence of the flight environment, a more comprehensive integrated design from a holistic perspective is achieved, making the design results more accurate. The thermal protection structure based on this design has less redundancy and lower cost. The aerodynamic data and thermal protection structure data after each design are completed can be saved as thermal protection data, providing technical reference for the development of subsequent new models, greatly improving thermal design efficiency and offering strong scalability. Transient design calculations can be performed, which is more intuitive and accurate compared to steady-state calculations.

[0071] Furthermore, the design methods for aircraft thermal protection structures also include:

[0072] If the temperature-time relationship does not meet the design requirements, return to the step of determining the protective materials for each part of the aircraft's thermal protection structure based on aerodynamic thermal data to re-specify the protective materials, and continue with the steps following the determination of the protective materials for each part of the aircraft's thermal protection structure based on aerodynamic thermal data.

[0073] In some embodiments, when the design of a thermal protection structure may require multiple adjustments to the protective materials and corresponding physical property parameters of each part, the protective materials of each part can be readjusted. All or part of the protective materials can be adjusted, and after the new protective materials are determined, the subsequent steps can be performed to complete the new design and verification.

[0074] The embodiments of the present invention have the following technical effects: by combining the aforementioned thermal protection material data, the solution can be iterated quickly; the thermal protection structure solutions can be compared in all aspects from multiple dimensions such as gravity and temperature.

[0075] Furthermore, the thermal protection structure includes: an external insulation layer, an internal insulation layer, and a cavity layer between the external insulation layer and the internal insulation layer.

[0076] Optionally, the thermal protection structure may also include an intermediate thermal insulation layer located between the outer thermal insulation layer and the inner thermal insulation layer. The number of intermediate thermal insulation layers can be one, two, or multiple. Correspondingly, any type of cavity layer may be provided between the outer thermal insulation layer and the intermediate thermal insulation layer, between the intermediate thermal insulation layer and the inner thermal insulation layer, or between each intermediate thermal insulation layer, or without a cavity layer.

[0077] Based on aerodynamic thermal data and the physical properties of the protective materials in each part of the thermal protection structure, and according to the principles of thermal convection, thermal radiation, and thermal conduction, the relationship between the temperature of the thermal protection structure and time is analyzed and determined, including:

[0078] Based on the physical properties and aerodynamic thermal data of the protective materials of the external insulation layer, internal insulation layer, and cavity layer, thermal convection, thermal radiation, and thermal conduction analyses are performed on the external insulation layer, cavity layer, and internal insulation layer to determine the relationship between the temperature of the thermal protection structure and time.

[0079] In some embodiments, such as Figure 3 As shown, the thermal protection structure includes: an outer thermal insulation layer 301, an inner thermal insulation layer 303, and a cavity layer 302 between the outer thermal insulation layer 301 and the inner thermal insulation layer 303; each layer has its own protective material; wherein, the protective material of the cavity layer can be, but is not limited to, air. Based on the determined aerodynamic thermal data and the protective materials and corresponding physical properties of each layer of the thermal protection structure, the relationship between the temperature of the thermal protection structure and time can be determined by analyzing each layer of the thermal protection structure in conjunction with the aerodynamic thermal data.

[0080] The embodiments of the present invention have the following technical effects: they can carry out the design of multi-layer thermal insulation materials with different thicknesses; they can clearly define the working time, thermal protection temperature and heat protection effect of each layer of thermal protection material, so as to carry out iterative optimization for each layer.

[0081] Furthermore, based on the physical properties and aerodynamic-thermal data of the protective materials of the external insulation layer, internal insulation layer, and cavity layer, thermal convection, thermal radiation, and thermal conduction analyses are performed on the external insulation layer, cavity layer, and internal insulation layer to determine the relationship between the temperature of the thermal protection structure and time, including:

[0082] Based on aerodynamic thermal data and the physical property parameters of the protective material of the external insulation layer, thermal convection and thermal radiation analysis were performed on the outer surface of the external insulation layer. The radiative heat transfer and convective heat transfer between the outer surface of the external insulation layer and the external environment were determined as the radiative heat transfer between the outer wall and the environment and the convective heat transfer between the outer wall and the environment.

[0083] The thermal conductivity of the external insulation layer is obtained by performing thermal conductivity analysis based on aerodynamic thermal data, radiative heat transfer between the outer wall and the environment, convective heat transfer between the outer wall and the environment, and the physical property parameters of the protective material of the external insulation layer.

[0084] Based on the thermal conductivity of the external insulation layer and the physical property parameters of the protective material of the cavity layer, the thermal conduction and thermal radiation of the cavity layer are analyzed to obtain the thermal conductivity and thermal radiation of the cavity layer.

[0085] Based on the thermal conductivity of the cavity layer, the radiative heat of the cavity layer, and the physical property parameters of the protective material of the internal insulation layer, the thermal conductivity of the internal insulation layer is analyzed.

[0086] Based on the thermal conductivity and protective material of the internal insulation layer, thermal convection and thermal radiation analysis of the internal insulation layer and the interior of the aircraft cabin are conducted to obtain the convective heat transfer between the internal insulation layer and the cabin and the radiative heat of the internal insulation layer.

[0087] Transient analysis was conducted based on aerodynamic thermal data, radiative heat transfer between the outer wall and the environment, thermal conduction of the external insulation layer, thermal conduction of the cavity layer, radiative heat of the cavity layer, thermal conduction of the internal insulation layer, convective heat transfer between the internal insulation layer and the cabin, and radiative heat of the internal insulation layer to obtain the relationship between the temperature of the aircraft's thermal protection structure and time.

[0088] In some embodiments, such as Figure 3 As shown, the thermal protection structure includes: an outer thermal insulation layer 301, an inner thermal insulation layer 303, and a cavity layer 302 between the outer thermal insulation layer 301 and the inner thermal insulation layer 303; it can be based on aerodynamic thermal data (i.e. Figure 3 The Q1 of the thermal protection structure, along with the protective materials and corresponding physical properties of each layer, is analyzed sequentially from the outside in to determine the temperature change of the thermal protection structure over time. The external thermal insulation layer is the outermost layer of the aircraft, in contact with the air outside the aircraft. Aerodynamic heat acts on the surface of the outer wall 31 of the external thermal insulation layer. Simultaneously, there is convective and radiative heat transfer between the outer wall 31 of the external thermal insulation layer and the external air. Therefore, based on aerodynamic heat data and the corresponding physical properties of the protective materials of the external thermal insulation layer, thermal convection and radiation analysis of the outer surface of the external thermal insulation layer is required. This analysis determines the radiative and convective heat transfer between the outer surface of the external thermal insulation layer (i.e., the outer wall 31 of the external thermal insulation layer) and the external environment, corresponding to the radiative and convective heat transfer between the outer wall and the environment (the radiative and convective heat transfer between the outer wall and the environment are...). Figure 3(represented uniformly by Q2), thus, based on aerodynamic heat data, radiative heat transfer between the outer wall and the environment, convective heat transfer between the outer wall and the environment, and the physical property parameters corresponding to the protective material of the outer insulation layer, the thermal conductivity of the outer insulation layer Q3 can be obtained by performing thermal conductivity analysis on the outer insulation layer; the cavity layer 302 is located between the outer insulation layer and the inner insulation layer. The thermal conductivity of the outer insulation layer will act on the cavity layer 302 through the inner wall 32 of the outer insulation layer. The cavity layer 302 has both thermal conduction and thermal radiation. Based on the thermal conductivity of the outer insulation layer and the physical property parameters corresponding to the protective material of the cavity layer 302, the thermal conduction and thermal radiation of the cavity layer can be obtained by performing thermal conduction and thermal radiation analysis on the cavity layer (the thermal conduction and thermal radiation of the cavity layer are...). Figure 3 (represented uniformly by Q4) The heat conduction and radiation of the cavity layer will continue to act on the outer wall 33 of the internal insulation layer. Based on the heat conduction, radiation, and physical property parameters of the protective material of the cavity layer, the heat conduction of the internal insulation layer is analyzed to obtain the heat conduction Q5 of the internal insulation layer. The heat conduction of the internal insulation layer acts on the interior of the aircraft cabin through the inner wall 34 of the internal insulation layer via heat convection and heat radiation. Based on the heat conduction and protective material of the internal insulation layer, the relationship between the internal insulation layer and the aircraft is analyzed. Thermal convection and thermal radiation analyses were performed inside the cabin to obtain the convective heat transfer Q6 between the internal insulation layer and the cabin and the radiative heat Q7 of the internal insulation layer. After the aforementioned process, heat transfer analysis was performed on each layer of the thermal protection structure. Finally, based on aerodynamic thermal data, radiative heat transfer between the outer wall and the environment, thermal conduction of the external insulation layer, thermal conduction of the cavity layer, radiative heat of the cavity layer, thermal conduction of the internal insulation layer, convective heat transfer between the internal insulation layer and the cabin, and radiative heat of the internal insulation layer, transient analysis was performed to obtain the relationship between the temperature of the aircraft's thermal protection structure and time. The theoretical formulas used for the thermal convection analysis in this embodiment of the invention are: formula (1), the theoretical formulas used for the thermal radiation analysis are: formula (2), the theoretical formulas used for the thermal conduction analysis are: formula (3), and the theoretical formulas used for the transient analysis are: formula (4). The specific formulas are as follows.

[0089] Thermal convection analysis is performed based on the convective heat transfer calculation formula:

[0090] q=h×ΔT formula (1)

[0091] Radiative heat dissipation analysis based on the fourth power law of radiation:

[0092] q=σ×ε×T 4 Formula (2)

[0093] Heat conduction analysis based on Fourier's law:

[0094] Formula (3) q=-λ×ΔT / δ

[0095] By introducing the thermal diffusivity coefficient, the heat conduction process inside the material at time t is calculated, and transient calculations are performed:

[0096] Formula (4) α=λ / ρ / C

[0097]

[0098] Write a program based on the above formulas (1-5) to solve for the numerical solution:

[0099]

[0100] The relationship between material temperature and heat flow and time was obtained.

[0101] In formula (1), q represents the convective heat transfer of the heat flow, with units of W / m³. 2 h is the convective heat transfer coefficient, in W / (m³). 2 K); ΔT is the temperature difference, in K; q in formula (2) is the radiant heat of the heat flow, in W / m³. 2 σ-Stephen Boltzmann constant, with a value of 5.678 × 10⁻⁶. -8 W / m 2 / K 4 ε is emissivity; T is temperature, in K; q in formula (3) is the heat conduction of the heat flux, in W / m³. 2 λ is the thermal conductivity, in W / (mK); δ is the material thickness, in m (meter); ρ in formula (4) is the density, in kg / m³. 3 (kg / m³); α is the thermal diffusivity, unit m. 2 / s (square meters per second); C is the specific heat capacity unit J / (kgK); in formula (5), x is the spatial coordinate; q is the net heat of the heat flow, with the unit W / m 2 In formula (6), Δt is the integration time step; T p The temperature at point p; T p0 The initial temperature at point p; T N , nodal temperature; A, cross-sectional area; Δx, distance between adjacent grid centers; where W is the power unit, watt; m is the length unit, meter; m 2 K is a unit of area, square meters; K is a unit of temperature, Kelvin; kg is a unit of weight, kilogram; J is a unit of heat, joule.

[0102] The embodiments of this invention have the following technical advantages: By comprehensively considering the characteristics of aerodynamic heat, thermal protection structure, and cabin environment, the design of thermal protection schemes is more accurate. Using engineering algorithms, thermal protection schemes can be designed conveniently, quickly, and rapidly, greatly saving manpower, material resources, and financial costs. Multi-layered thermal protection design comprehensively considers the cabin and flight environment. Furthermore, it comprehensively considers the aerodynamic heat of the flight environment, the radiation of multi-layered thermal protection materials, internal heat conduction, and the convective heat transfer process within the cabin. Furthermore, the use of transient theoretical calculation models allows for the rapid and convenient design and optimization of complex thermal protection structures. Through programmed and rapid calculations, the scheme achieves rapid iterative optimization.

[0103] Furthermore, the method also includes: the type of protective material includes, but is not limited to, metallic and non-metallic materials. Examples include, but are not limited to, materials such as gold, silver, copper, iron, aluminum, fiberglass, carbon fiber, asphalt, and paper honeycomb. The physical properties of each material include any one or more of the following: thermal conductivity, density, specific heat capacity, and emissivity.

[0104] Secondly, such as Figure 2 As shown, an embodiment of the present invention provides a device for designing a thermal protection structure for an aircraft, comprising:

[0105] Aerodynamic thermal data determination unit 20 is used to perform aerodynamic thermal calculations based on the flight conditions of the aircraft to obtain aerodynamic thermal data.

[0106] The protective material determination unit 21 is used to determine the protective materials of each part of the thermal protection structure of the aircraft based on aerodynamic thermal data, and to obtain the physical property parameters corresponding to the protective materials of each part of the thermal protection structure.

[0107] The temperature-time relationship determination unit 22 is used to analyze the thermal protection structure based on aerodynamic thermal data and the physical property parameters of the protective materials of each part of the thermal protection structure, and based on the principles of thermal convection, thermal radiation and thermal conduction, to determine the relationship between the temperature of the thermal protection structure and time.

[0108] The design result output unit 23 is used to compare the relationship between temperature and time with the preset thermal protection design requirements. If the relationship between temperature and time meets the preset thermal protection design requirements, the output unit will output the relationship between temperature and time, the protective materials of each part of the thermal protection structure and the corresponding physical property parameters.

[0109] Furthermore, the aircraft thermal protection structure design device also includes:

[0110] The redesign unit is used to re-trigger the protective material determination unit if the temperature-time relationship does not meet the design requirements, and to continue triggering the temperature-time relationship determination unit and the design result output unit.

[0111] Furthermore, the thermal protection structure includes: an external thermal insulation layer, an internal thermal insulation layer, and a cavity layer between the external thermal insulation layer and the internal thermal insulation layer;

[0112] The temperature-time relationship determination unit 22 is specifically used to: perform thermal convection, thermal radiation, and thermal conduction analysis on the external insulation layer, the internal insulation layer, and the cavity layer based on the physical property parameters and aerodynamic thermal data of the protective materials of each of them, and determine the relationship between the temperature of the thermal protection structure and time.

[0113] Furthermore, the temperature-time relationship determination unit 22 includes:

[0114] The outer wall radiative heat determination module is used to perform thermal convection and thermal radiation analysis on the outer surface of the outer insulation layer based on aerodynamic thermal data and the physical property parameters corresponding to the protective material of the outer insulation layer, and to determine the radiative heat transfer and convective heat transfer between the outer surface of the outer insulation layer and the external environment as the corresponding radiative heat transfer and convective heat transfer between the outer wall and the environment.

[0115] The outer wall thermal conductivity determination module is used to perform thermal conduction analysis on the outer insulation layer based on aerodynamic thermal data, radiative heat transfer between the outer wall and the environment, convective heat transfer between the outer wall and the environment, and the physical property parameters of the protective material of the outer insulation layer to obtain the thermal conductivity of the outer insulation layer.

[0116] The cavity radiation thermal conductivity determination module is used to perform thermal conduction and thermal radiation analysis on the cavity layer based on the thermal conductivity of the external insulation layer and the physical property parameters of the protective material of the cavity layer to obtain the cavity layer thermal conductivity and cavity layer radiation thermal conductivity.

[0117] The internal insulation layer thermal conductivity determination module is used to perform thermal conduction analysis on the internal insulation layer based on the thermal conductivity of the cavity layer, the radiative heat of the cavity layer, and the physical property parameters of the protective material of the internal insulation layer, so as to obtain the thermal conductivity of the internal insulation layer.

[0118] The module for determining the convection and radiation heat between the internal insulation layer and the cabin is used to perform thermal convection and thermal radiation analysis on the internal insulation layer and the cabin interior of the aircraft based on the thermal conductivity of the internal insulation layer and the protective material of the internal insulation layer to obtain the convective heat transfer between the internal insulation layer and the cabin and the radiation heat of the internal insulation layer.

[0119] The temperature-time relationship determination module is used to perform transient analysis based on aerodynamic thermal data, radiative heat transfer between the outer wall and the environment, thermal conduction of the external insulation layer, thermal conduction of the cavity layer, radiative heat of the cavity layer, thermal conduction of the internal insulation layer, convective heat transfer between the internal insulation layer and the cabin, and radiative heat of the internal insulation layer to obtain the relationship between the temperature of the aircraft's thermal protection structure and time.

[0120] The embodiments of this invention have the following technical advantages: By comprehensively considering the characteristics of aerodynamic heat, thermal protection structure, and cabin environment, the design of thermal protection schemes is more accurate. Using engineering algorithms, thermal protection schemes can be designed conveniently, quickly, and rapidly, greatly saving manpower, material resources, and financial costs. Multi-layered thermal protection design comprehensively considers the cabin and flight environment. Furthermore, it comprehensively considers the aerodynamic heat of the flight environment, the radiation of multi-layered thermal protection materials, internal heat conduction, and the convective heat transfer process within the cabin. Furthermore, the use of transient theoretical calculation models allows for the rapid and convenient design and optimization of complex thermal protection structures. Through programmed and rapid calculations, the scheme achieves rapid iterative optimization.

[0121] Thirdly, an embodiment of the present invention provides a readable storage medium storing program code for implementing any of the aircraft thermal protection structure design methods of the first aspect.

[0122] The embodiments of this invention have the following technical advantages: By comprehensively considering the characteristics of aerodynamic heat, thermal protection structure, and cabin environment, the design of thermal protection schemes is more accurate. Using engineering algorithms, thermal protection schemes can be designed conveniently, quickly, and rapidly, greatly saving manpower, material resources, and financial costs. Multi-layered thermal protection design comprehensively considers the cabin and flight environment. Furthermore, it comprehensively considers the aerodynamic heat of the flight environment, the radiation of multi-layered thermal protection materials, internal heat conduction, and the convective heat transfer process within the cabin. Furthermore, the use of transient theoretical calculation models allows for the rapid and convenient design and optimization of complex thermal protection structures. Through programmed and rapid calculations, the scheme achieves rapid iterative optimization.

[0123] The technical solutions of the present invention will be described in detail below with reference to specific application examples. For technical details not described in the implementation process, please refer to the relevant descriptions above.

[0124] like Figure 3 As shown in the heat transfer analysis model of the thermal protection structure in this embodiment of the invention, the outer surface of the upper material (i.e., the outer wall 31 of the outer heat insulation layer) is the outer surface of the aircraft's thermal protection material. During the entire flight, the aerodynamic heat of the outer surface (equivalent to the outer wall 31 of the outer heat insulation layer) continuously heats the thermal protection structure, and the outer surface (equivalent to the outer wall 31 of the outer heat insulation layer) continuously radiates heat to the external environment; the inner surface of the lower material (i.e., the inner wall 34 of the inner heat insulation layer) is the inner surface of the cabin structure or another thermal protection material, which exchanges heat with the cabin air through radiation and convection; the upper material (i.e., the outer heat insulation layer 301) and the lower material (i.e., the inner heat insulation layer 303) exchange heat through radiation and conduction via the cavity layer 302.

[0125] Based on such Figure 3The thermal protection structure shown in this embodiment of the invention provides a thermal protection design method for aircraft, which is also a transient passive thermal protection design method for aircraft, including:

[0126] Determine the input conditions, including flight speed, flight environment, cabin environment, and material properties such as thermal conductivity, density, temperature resistance, and thickness.

[0127] Calculate the heat flux density at the stagnation point of a ball head, a flat plate, a typical cylindrical component, and a cone;

[0128] The calculated aerodynamic and thermal data serve as input conditions for the design of thermal protection structures;

[0129] Based on the changing relationships of thermal conduction, radiation, and convection heat transfer, a theoretical analysis is conducted on the thermal protection structure used under these boundary conditions, and it is determined whether it meets the thermal protection design requirements.

[0130] The specific steps are as follows:

[0131] Aerodynamic and thermal calculations were performed based on the flight conditions of the aircraft.

[0132] The design conditions are used as input conditions for thermal protection design; the design conditions are the results obtained after selecting the flight conditions of the aircraft and performing aerodynamic and thermal calculations.

[0133] Using theoretical calculation methods based on thermal convection, thermal radiation, and thermal conduction, the following calculations were performed: radiative heat transfer between the outer wall and the environment; convective heat transfer between the outer wall and the environment; thermal conduction of the external insulation layer; thermal conduction of the cavity layer; radiative heat transfer of the cavity layer; thermal conduction of the internal insulation layer; convective heat transfer between the internal insulation layer and the cabin; radiative heat transfer of the internal insulation layer; and the temperature variation of the thermal protection layer and structural layer over time.

[0134] The technical solution of the present invention will be described below with reference to another embodiment:

[0135] This invention provides a method for designing and calculating transient passive thermal protection for aircraft. In this embodiment, the thermal protection structure and heat transfer model of the rocket fairing are as follows: Figure 3 As shown. The specific steps are as follows:

[0136] Record the types of protective materials used in each part of the thermal protection structure, as well as the corresponding physical properties of each type of material, such as thermal conductivity, density, specific heat capacity, and emissivity. The types of protective materials include, but are not limited to, metallic and non-metallic materials. For example, these include, but are not limited to, protective materials such as gold, silver, copper, iron, aluminum, fiberglass, carbon fiber, asphalt, and paper honeycomb.

[0137] The MATLAB platform was used to write a program for aerodynamic and thermal protection design calculations of aircraft, and to obtain the recorded physical property parameters of protective materials.

[0138] For the aerodynamic thermal environment of the rocket fairing, aerodynamic heat flux calculations were performed to obtain the initial aerodynamic thermal data:

[0139] Specifically, the aerodynamic thermal data obtained includes, but is not limited to, aerodynamic thermal data cold wall heat flux and wall surface temperature, and the obtained aerodynamic thermal data is used as input conditions for the design of thermal protection structures.

[0140] Based on aerodynamic thermal data, the protective materials for each part of the aircraft's thermal protection structure are selected, and the corresponding physical property parameters of the protective materials for each part of the thermal protection structure are obtained. The physical property parameters include, but are not limited to, thermal conductivity λ (unit W / (mK)), emissivity ε, specific heat capacity C (unit J / (kg)), and density ρ (unit kg / m³). 3 ), and / or thermal diffusivity α (unit: m 2 / s).

[0141] Convection heat transfer analysis is performed based on the convective heat transfer calculation formula (1); radiation heat dissipation analysis is performed based on the formula (2) corresponding to the fourth power law of radiation; thermal conductivity analysis is performed based on the Fourier law according to the formula (3); thermal diffusion coefficient is introduced according to the formula (4) to calculate the heat conduction process inside the material at time t, and transient analysis and calculation are performed.

[0142] By using aerodynamic heating as input for thermal protection design, and performing calculations on the convection, radiation, and thermal conduction of thermal protection materials, the relationship between the material wall surface and the ambient temperature inside the cabin and time can be obtained.

[0143] When a rocket is subjected to high temperatures for a short period, relevant parameters can be treated as functions of time, such as λ(t). Finally, the parameters calculated at time t, such as the internal temperature and the mass of the thermal protection structure, are compared with the design requirements. If the design requirements are met, the calculation is complete, and the output results are provided. These output results include, but are not limited to, the changes in material thickness and wall temperature over time. Otherwise, the parameters of the thermal protection structure materials are changed, and the design calculation is repeated.

[0144] The embodiments of this invention have the following technical advantages: By comprehensively considering the characteristics of aerodynamic heat, thermal protection structure, and cabin environment, the design of thermal protection schemes is more accurate. Using engineering algorithms, thermal protection schemes can be designed conveniently, quickly, and rapidly, greatly saving manpower, material resources, and financial costs. Multi-layered thermal protection design comprehensively considers the cabin and flight environment. Furthermore, it comprehensively considers the aerodynamic heat of the flight environment, the radiation of multi-layered thermal protection materials, internal heat conduction, and the convective heat transfer process within the cabin. Furthermore, the use of transient theoretical calculation models allows for the rapid and convenient design and optimization of complex thermal protection structures. Through programmed and rapid calculations, the scheme achieves rapid iterative optimization.

[0145] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process may be rearranged without departing from the scope of this disclosure. The appended method claims provide elements of various steps in an exemplary order and are not intended to limit the scope to a specific order or hierarchy.

[0146] In the above detailed description, various features are combined together in a single embodiment to simplify this disclosure. This approach to disclosure should not be construed as reflecting an intention that embodiments of the claimed subject matter require more features than are explicitly stated in each claim. Rather, as reflected in the appended claims, the invention is presented with fewer features than all of the features of the single disclosed embodiment. Therefore, the appended claims are hereby explicitly incorporated into the detailed description, wherein each claim stands alone as a preferred embodiment of the invention.

[0147] The disclosed embodiments have been described above to enable any person skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments without departing from the spirit and scope of this disclosure. Therefore, this disclosure is not limited to the embodiments given herein, but is consistent with the broadest scope of the principles and novel features disclosed in this application.

[0148] The foregoing description includes examples of one or more embodiments. It is certainly impossible to describe all possible combinations of components or methods in order to describe the above embodiments, but those skilled in the art will recognize that further combinations and arrangements of the various embodiments are possible. Therefore, the embodiments described herein are intended to cover all such changes, modifications, and variations falling within the scope of the appended claims. Furthermore, the term "comprising" as used in the specification or claims is used in a manner similar to the term "including." Additionally, the use of any term "or" in the specification of the claims is intended to mean "non-exclusive or."

[0149] Those skilled in the art will also understand that the various illustrative logical blocks, units, and steps listed in the embodiments of the present invention can be implemented by electronic hardware, computer software, or a combination of both. To clearly demonstrate the interchangeability of hardware and software, the functions of the various illustrative components, units, and steps described above have been generally described. Whether such functionality is implemented through hardware or software depends on the specific application and the overall system design requirements. Those skilled in the art can implement the described functions using various methods for each specific application, but such implementation should not be construed as exceeding the scope of protection of the embodiments of the present invention.

[0150] The various illustrative logic blocks or units described in the embodiments of this invention can be implemented or operate the described functions using a general-purpose processor, digital signal processor, application-specific integrated circuit (ASIC), field-programmable gate array or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof. The general-purpose processor can be a microprocessor; alternatively, it can be any conventional processor, controller, microcontroller, or state machine. The processor can also be implemented using a combination of computing devices, such as a digital signal processor and a microprocessor, multiple microprocessors, one or more microprocessors combined with a digital signal processor core, or any other similar configuration.

[0151] The steps of the methods or algorithms described in the embodiments of this invention can be directly embedded in hardware, a software module executed by a processor, or a combination of both. The software module can be stored in RAM, flash memory, ROM, EPROM, EEPROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium in the art. Exemplarily, the storage medium can be connected to the processor so that the processor can read information from and write information to the storage medium. Optionally, the storage medium can also be integrated into the processor. The processor and storage medium can be housed in an ASIC, which can be housed in a user terminal. Optionally, the processor and storage medium can also be housed in different components of the user terminal.

[0152] In one or more exemplary designs, the functions described in the embodiments of the present invention can be implemented in hardware, software, firmware, or any combination of these three. If implemented in software, these functions can be stored on a computer-readable medium or transmitted on a computer-readable medium in the form of one or more instructions or code. Computer-readable media include computer storage media and communication media that facilitate the transfer of computer programs from one place to another. Storage media can be any available media that can be accessed by a general-purpose or special-purpose computer. For example, such computer-readable media can include, but is not limited to, RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store program code in the form of instructions or data structures and other forms that can be read by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Furthermore, any connection can be suitably defined as a computer-readable medium, for example, if the software is transmitted from a website, server or other remote resource via a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) or wirelessly, such as infrared, wireless and microwave, it is also included in the defined computer-readable medium. The disks and discs mentioned include compressed disks, laser discs, optical discs, DVDs, floppy disks, and Blu-ray discs. Disks typically copy data magnetically, while disks typically copy data optically using lasers. Combinations of the above can also be contained in computer-readable media.

[0153] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A design method for a thermal protection structure of an aircraft, characterized in that, include: Aerodynamic and thermal data are obtained by performing aerodynamic and thermal calculations based on the flight conditions of the aircraft. Based on the aerodynamic thermal data, the protective materials for each part of the thermal protection structure of the aircraft are selected, and the physical property parameters corresponding to the protective materials for each part of the thermal protection structure are obtained. Based on the aerodynamic thermal data and the physical property parameters of the protective materials of each part of the thermal protection structure, and according to the principles of thermal convection, thermal radiation and thermal conduction, the thermal protection structure is analyzed to determine the relationship between the temperature of the thermal protection structure and time. The relationship between temperature and time is compared with the preset thermal protection design requirements. If the relationship between temperature and time meets the preset thermal protection design requirements, the relationship between temperature and time, the protective materials of each part of the thermal protection structure, and the corresponding physical property parameters are output.

2. The aircraft thermal protection structure design method as described in claim 1, characterized in that, The method further includes: If the temperature change over time does not meet the preset thermal protection design requirements, then return to the step of determining the protective materials of each part of the thermal protection structure of the aircraft based on the aerodynamic thermal data, so as to reselect the protective materials of each part of the thermal protection structure, and continue to execute the steps after selecting the protective materials of each part of the thermal protection structure of the aircraft based on the aerodynamic thermal data and obtaining the physical property parameters corresponding to the protective materials of each part of the thermal protection structure.

3. The aircraft thermal protection structure design method as described in claim 1, characterized in that, The thermal protection structure includes: an outer heat insulation layer, an inner heat insulation layer, and a cavity layer between the outer heat insulation layer and the inner heat insulation layer; The step of analyzing and determining the temperature change of the thermal protection structure over time based on the aerodynamic thermal data and the physical properties of the protective materials of each part of the thermal protection structure, and according to the principles of thermal convection, thermal radiation, and thermal conduction, includes: Based on the physical property parameters of the protective materials of the external insulation layer, the internal insulation layer, and the cavity layer, and the aerodynamic thermal data, thermal convection, thermal radiation, and thermal conduction analyses are performed on the external insulation layer, the cavity layer, and the internal insulation layer to determine the relationship between the temperature of the thermal protection structure and time.

4. The aircraft thermal protection structure design method as described in claim 3, characterized in that, The step of determining the temperature change over time of the thermal protection structure by performing thermal convection, thermal radiation, and thermal conduction analysis on the external thermal insulation layer, the internal thermal insulation layer, and the cavity layer based on the physical property parameters of their respective protective materials and the aerodynamic thermal data includes: Based on the aerodynamic thermal data and the physical property parameters corresponding to the protective material of the external insulation layer, thermal convection and thermal radiation analysis are performed on the outer surface of the external insulation layer to determine the radiation heat transfer and convection heat transfer between the outer surface of the external insulation layer and the external environment as the radiation heat transfer and convection heat transfer between the outer wall and the environment. Based on the aerodynamic heat data, the radiative heat transfer between the outer wall and the environment, the convective heat transfer between the outer wall and the environment, and the physical property parameters corresponding to the protective material of the external insulation layer, the thermal conductivity of the external insulation layer is analyzed to obtain the thermal conductivity of the external insulation layer. Based on the thermal conductivity of the external insulation layer and the physical property parameters corresponding to the protective material of the cavity layer, thermal conduction and thermal radiation analysis of the cavity layer are performed to obtain the thermal conductivity and radiative heat of the cavity layer. Based on the thermal conductivity of the cavity layer, the radiative heat of the cavity layer, and the physical property parameters corresponding to the protective material of the internal insulation layer, the thermal conductivity of the internal insulation layer is analyzed. Based on the thermal conductivity of the internal insulation layer and the protective material of the internal insulation layer, thermal convection and thermal radiation analysis are performed on the internal insulation layer and the interior of the aircraft cabin to obtain the convective heat transfer between the internal insulation layer and the cabin and the radiative heat of the internal insulation layer. Based on the aerodynamic thermal data, the radiative heat of the outer wall and the environment, the thermal conductivity of the external insulation layer, the thermal conductivity of the cavity layer, the radiative heat of the cavity layer, the thermal conductivity of the internal insulation layer, the convective heat transfer between the internal insulation layer and the cabin, and the radiative heat of the internal insulation layer, transient analysis is performed to obtain the relationship between the temperature of the aircraft's thermal protection structure and time.

5. The aircraft thermal protection structure design method as described in claim 1, characterized in that, The method further includes: the physical property parameters corresponding to the protective materials of each part of the thermal protection structure include any one or more of the following: thermal conductivity, density, specific heat capacity, and emissivity.

6. A design device for a thermal protection structure of an aircraft, characterized in that, include: The aerodynamic thermal data determination unit is used to perform aerodynamic thermal calculations based on the flight conditions of the aircraft to obtain aerodynamic thermal data. The protective material determination unit is used to determine the protective material of each part of the thermal protection structure of the aircraft based on the aerodynamic thermal data, and to obtain the physical property parameters corresponding to the protective material of each part of the thermal protection structure. The temperature-time relationship determination unit is used to analyze and determine the temperature-time relationship of the thermal protection structure based on the aerodynamic thermal data and the physical property parameters of the protective materials of each part of the thermal protection structure, and based on the principles of thermal convection, thermal radiation and thermal conduction. The design result output unit is used to compare the relationship between temperature and time with the preset thermal protection design requirements. If the relationship between temperature and time meets the preset thermal protection design requirements, the unit outputs the relationship between temperature and time, the protective materials of each part of the thermal protection structure, and the corresponding physical property parameters.

7. The aircraft thermal protection structure design device as described in claim 6, characterized in that, The device further includes: The redesign unit is used to re-trigger the protective material determination unit and continue to trigger the temperature-time relationship determination unit and the design result output unit if the temperature-time relationship does not meet the design requirements.

8. The aircraft thermal protection structure design device as described in claim 6, characterized in that, The thermal protection structure includes: an outer heat insulation layer, an inner heat insulation layer, and a cavity layer between the outer heat insulation layer and the inner heat insulation layer; The temperature-time relationship determination unit is specifically used to: perform thermal convection, thermal radiation, and thermal conduction analysis on the external thermal insulation layer, the internal thermal insulation layer, and the cavity layer based on the physical property parameters of the protective materials of each of the external thermal insulation layer, the internal thermal insulation layer, and the cavity layer, and the aerodynamic thermal data, to determine the relationship between the temperature of the thermal protection structure and time.

9. The aircraft thermal protection structure design device as described in claim 8, characterized in that, The temperature-time relationship determination unit includes: The outer wall radiative heat determination module is used to perform thermal convection and thermal radiation analysis on the outer surface of the outer heat insulation layer based on the aerodynamic thermal data and the physical property parameters corresponding to the protective material of the outer heat insulation layer, and to determine the radiative heat transfer and convective heat transfer between the outer surface of the outer heat insulation layer and the external environment as the corresponding radiative heat transfer and convective heat transfer between the outer wall and the environment. The outer wall thermal conductivity determination module is used to perform thermal conduction analysis on the outer insulation layer based on the aerodynamic heat data, the radiation heat exchange between the outer wall and the environment, the convection heat exchange between the outer wall and the environment, and the physical property parameters corresponding to the protective material of the outer insulation layer to obtain the thermal conductivity of the outer insulation layer. The cavity radiation thermal conductivity determination module is used to perform thermal conduction and thermal radiation analysis on the cavity layer based on the thermal conductivity of the external insulation layer and the physical property parameters corresponding to the protective material of the cavity layer to obtain the cavity layer thermal conductivity and cavity layer radiation thermal conductivity. The internal insulation layer thermal conductivity determination module is used to perform thermal conduction analysis on the internal insulation layer based on the thermal conductivity of the cavity layer, the radiant heat of the cavity layer, and the physical property parameters corresponding to the protective material of the internal insulation layer, so as to obtain the thermal conductivity of the internal insulation layer. The module for determining the convection and radiation heat between the internal insulation layer and the cabin is used to perform thermal convection and thermal radiation analysis on the internal insulation layer and the cabin interior of the aircraft based on the thermal conductivity of the internal insulation layer and the protective material of the internal insulation layer to obtain the convective heat transfer between the internal insulation layer and the cabin and the radiation heat of the internal insulation layer. The temperature-time relationship determination module is used to perform transient analysis based on the aerodynamic heat data, the radiative heat exchange between the outer wall and the environment, the heat conduction of the external insulation layer, the heat conduction of the cavity layer, the radiative heat of the cavity layer, the heat conduction of the internal insulation layer, the convective heat exchange between the internal insulation layer and the cabin, and the radiative heat of the internal insulation layer, to obtain the temperature-time relationship of the thermal protection structure of the aircraft.

10. A readable storage medium, characterized in that, It stores program code for implementing the aircraft thermal protection structure design method as described in any one of claims 1-5.

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