A structural-functional integrated thermal design method

Abstract

This application belongs to the field of aircraft overall design and functional structure design, and particularly relates to a structural-functional integrated thermal design method. It includes: clarifying the functional structure design boundary through requirements analysis; comprehensively considering the basic characteristics and technical feasibility of the material database, active cooling structure configuration database, and manufacturing process database, and conducting technical option demonstration under the structural geometric constraint conditions; identifying the structural flow channel design parameters and active cooling system design parameters, combining with the experiments of key parameter components, analyzing the influence laws on the structural heat transfer and heat exchange characteristics, summarizing the key parameter groups of the structural-functional integrated thermal design, and selecting the structural flow channel design parameters and active cooling system design parameters according to the action effects to complete the scheme design; hierarchically decomposing the functional structure comprehensive evaluation index system from multiple dimensions, and completing the scheme evaluation and parameter optimization design according to the evaluation requirements; completing the thermo-mechanical coupling test of typical functional structure test pieces under simulated thermal conditions.

Description

Technical Field

[0001] This application belongs to the field of aircraft overall design and functional structure design, and particularly relates to an integrated structural-functional thermal design method. Background Art

[0002] During long-duration flight, high Mach number aircraft will endure a severe force / heat coupling environment, which causes local structural overheating and large temperature gradients on the aircraft surface, generating significant structural thermal stress. Existing thermal structure / thermal protection designs mostly rely on passive thermal protection to resist, and passive thermal protection structures that rely on the temperature resistance of materials are difficult to meet the usage requirements of local overheating and long-duration multi-field environments. Arranging active cooling channels within the structure can effectively solve the problem of structural overheating through the integrated design of the active cooling function and the structure body, but it is necessary to comprehensively achieve the load-bearing and thermal protection functions of the active cooling functional structure.

[0003] The integrated design of high Mach number aircraft's high-temperature and high-heat structures and active cooling functions faces the cross-design challenges of aerodynamic heat, thermal protection, and active cooling systems, and is affected by key parameters in multiple dimensions across different specialties, which brings great challenges to comprehensively achieving the load-bearing and thermal protection functions of the active cooling structure.

[0004] Therefore, it is desirable to have a technical solution to overcome or at least mitigate at least one of the above defects of the existing technology. Summary of the Invention

[0005] The purpose of this application is to provide an integrated structural-functional thermal design method to solve at least one problem existing in the prior art.

[0006] The technical solution of this application is as follows:

[0007] An integrated structural-functional thermal design method includes:

[0008] Step 1: Define the boundary of functional structure design through requirement analysis;

[0009] Step 2: Based on the basic characteristics and technical feasibility of the material database, active cooling structure configuration database, and manufacturing process database, conduct technical selection and demonstration under the structural geometric constraint conditions;

[0010] Step 3: Identify the design parameters of the structural flow channels and the active cooling system, combine with experiments on key parameter components, analyze the influence laws of these parameters on the heat transfer and heat exchange characteristics of the structure, summarize the key parameter groups of the integrated structural-functional thermal design, and select the design parameters of the structural flow channels and the active cooling system according to the action effects to complete the scheme design;

[0011] Step 4: Facing the functional and performance requirements of practical applications, hierarchically decompose the comprehensive evaluation index system of the functional structure from multiple dimensions, and complete the scheme evaluation and parameter optimization design according to the evaluation requirements;

[0012] Step 5: Conduct the thermo-mechanical coupling test on the typical functional structure test piece under the simulated thermal conditions.

[0013] In at least one embodiment of the present application, in Step 1, the requirement analysis includes the thermal protection requirement analysis, the load-bearing requirement analysis, and the reusable requirement analysis.

[0014] In at least one embodiment of the present application, in Step 2,

[0015] The material database includes the performance database of the cooling medium and the performance database of the structural material;

[0016] The active cooling configuration database includes the straight channel database, the fractal channel database, and the topological channel database;

[0017] The manufacturing process database includes the additive manufacturing database, the machining database, and the precision casting database.

[0018] In at least one embodiment of the present application, in Step 3,

[0019] The structural channel design parameters include the channel cross-sectional size, the channel cross-sectional shape, the channel length, the channel layout configuration, the number of channels, the channel spacing, and the channel surface state;

[0020] The active cooling system design parameters include the fluid type, the flow state, the flow rate, the flow velocity, the flow direction, the fluid inlet and outlet, and the driving pump power.

[0021] In at least one embodiment of the present application, the channel cross-sectional shape includes rectangle, triangle, trapezoid, and circle.

[0022] In at least one embodiment of the present application, in Step 4, hierarchically decompose the comprehensive evaluation index system of the functional structure from four dimensions: basic performance, comprehensive support performance, achievable performance, and compensatory performance.

[0023] In at least one embodiment of the present application,

[0024] The basic performance includes the load-bearing performance and the heat protection performance;

[0025] The comprehensive support performance includes reliability, reusability, maintainability, and safety;

[0026] The achievable performance includes the machining performance and the assembly performance;

[0027] The compensation performance includes energy demand, compensation loss, and economy.

[0028] The invention has at least the following beneficial technical effects:

[0029] The integrated thermal design method of structure and function in this application follows the research ideas of requirement analysis, technical demonstration, scheme design, evaluation and optimization, and experimental verification, guiding the effective design process of integrating the active cooling function with the structure body, and is applicable to the active cooling function design of high-temperature and high-heat structures under high heat flux density and long-term operation. Description of the Drawings

[0030] Figure 1 is a flowchart of the integrated thermal design method of structure and function in an embodiment of this application;

[0031] Figure 2 is a schematic diagram of the elements of the material, active cooling structure configuration, and manufacturing process basic database in an embodiment of this application;

[0032] Figure 3 is a schematic diagram of the structural flow channel design parameters and active cooling system design parameters in an embodiment of this application;

[0033] Figure 4 is a schematic diagram of the integrated structural and functional evaluation index system in an embodiment of this application;

[0034] Figure 5 is a schematic diagram of the active cooling function structure designed based on the integrated thermal design method of structure and function in an embodiment of this application. Detailed Embodiments

[0035] To make the purpose, technical solutions, and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the drawings in the embodiments of this application. In the drawings, the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions throughout. The described embodiments are some, but not all, of the embodiments of this application. The embodiments described below with reference to the drawings are exemplary and are intended to explain this application and should not be construed as limiting this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of this application without creative efforts fall within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the drawings.

[0036] In the description of the present application, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the protection scope of the present application.

[0037] The following will further elaborate on the present application in conjunction with the Figures 1 to 5 drawings.

[0038] The present application provides an integrated structural and functional thermal design method, including the processes of requirement analysis, technical demonstration, scheme design, evaluation and optimization, and experimental verification.

[0039] Specifically, referring to Figure 1 , it includes the following steps:

[0040] Step 1: Define the design boundary of the functional structure through requirement analysis;

[0041] Step 2: Based on the basic characteristics and technical feasibility of the material database, active cooling structure configuration database, and manufacturing process database, conduct technical selection and demonstration under the structural geometric constraint conditions;

[0042] Step 3: Identify the design parameters of the structural flow channel and the active cooling system, and combined with the experiments of key parameter components, analyze the influence laws on the heat transfer and heat exchange characteristics of the structure, summarize the key parameter groups of the integrated structural and functional thermal design, and select the design parameters of the structural flow channel and the active cooling system according to the action effects to complete the scheme design;

[0043] Step 4: For the functional and performance requirements of actual applications, hierarchically decompose the comprehensive evaluation index system of the functional structure from multiple dimensions, and complete the scheme evaluation and parameter optimization design according to the evaluation requirements;

[0044] Step 5: Conduct a thermal-mechanical coupling test on the typical functional structure test piece under simulated thermal conditions.

[0045] In the preferred implementation of the present application, in Step 1, first define the design boundary of the functional structure through requirement analysis, mainly including the requirement analysis of functional performances such as thermal protection, load bearing, and reusability.

[0046] In the preferred implementation of the present application, in Step 2, based on the functional requirements, comprehensively consider the basic characteristics and technical feasibility of existing materials, active cooling structure configurations, and manufacturing processes, and conduct technical selection and demonstration under the structural geometric constraint conditions. In this embodiment, for example Figure 2As shown in the figure, the material database includes a cooling medium performance database and a structural material performance database. Among them, the cooling medium database includes material properties such as density, dynamic viscosity, thermal conductivity, specific heat capacity, diffusion coefficient, temperature resistance performance, phase change performance, and heat sink performance. The structural material performance database includes material properties such as thermal expansion coefficient, high-temperature oxidation performance, elastic modulus, Poisson's ratio, yield strength, high-temperature fatigue life, fracture toughness, and thermal shock resistance performance. The active cooling configuration database is mainly a geometric configuration database of different configuration channels such as straight channels, fractal channels, and topological channels. The manufacturing process database includes an additive manufacturing database, a machining database, and a precision casting database. Among them, the additive manufacturing types include powder feeding process and powder spreading process, and the machining types include machining + welding process and surface treatment process.

[0047] In a preferred embodiment of the present application, as Figure 3 shown, in step three, the structural channel design parameters include channel cross-sectional dimensions, channel cross-sectional shape, channel length, channel layout configuration, number of channels, channel spacing, and channel surface condition. The structural shape of the channel can be controlled by controlling the geometric parameters. Among them, the channel cross-sectional shape includes rectangle, triangle, trapezoid, and circle. The active cooling system design parameters include fluid type, flow state, flow rate, flow velocity, flow direction, fluid inlet and outlet, and driving pump power. The heat transfer performance of the fluid can be controlled by controlling the fluid state in the channel.

[0048] In a preferred embodiment of the present application, as Figure 4 shown, in step four, facing the functional and performance requirements of actual applications, the functional structure comprehensive evaluation index system is hierarchically decomposed from four dimensions: basic performance, comprehensive guarantee performance, achievable performance, and compensatory performance. The scheme evaluation and parameter optimization design are completed according to the evaluation requirements. In this embodiment, the basic performance includes load-bearing performance and heat protection performance. The comprehensive guarantee performance includes reliability, reusability, maintainability, and safety. The achievable performance includes machining performance and assembly performance. The compensatory performance includes energy demand, compensatory loss, and economy.

[0049] In a specific embodiment of the present application, first, the functional structure design boundary is clarified through requirement analysis. In this embodiment, the nose cone shell is a non-regular curvature cone structure. The stagnation region bears a high heat flux on a small area, and the large area at the rear bears a small heat flux. It is required to have functional and performance requirements such as the structure not exceeding the temperature, the thermal stress not exceeding the strength limit, and reusability under geometric constraints. Then, the basic materials and technical routes of the functional structure are selected through technical demonstration. According to Figure 2The selected elements of the material, active cooling structure configuration, and manufacturing process basic database shown. For the geometric shape and heat dissipation requirements of the nose cone structure in this embodiment, it is necessary to consider the high-temperature characteristics of the cooling medium and structural materials, comprehensively consider the characteristics of the active cooling configuration and its manufacturing process capabilities, and select the fractal configuration active cooling flow channel configuration that can be realized by additive manufacturing as the main technical route. Through the function of the scheme design to guide the parameter selection design of the functional structure, it mainly includes Figure 3 The structural flow channel design parameters and active cooling system design parameters shown. Combined with the experiments of key parameter components, analyze the influence laws of their effects on the structural heat transfer and heat exchange characteristics, summarize the key parameter groups of the integrated thermal design of the structural function, and guide the scheme design. Further, for the functional and performance requirements of practical applications, according to Figure 4 The comprehensive evaluation index system shown to comprehensively evaluate the nose cone functional structure in this embodiment, and realize the integrated optimization design of the flow channel configuration parameters and the cooling system design parameters. Finally, complete the thermal-mechanical coupling test of the typical functional structure test piece under the simulated thermal conditions, check and verify the functional performance of the embodiment model, so as to obtain the active cooling functional structure as shown in Figure 5 to meet the requirements.

[0050] The integrated thermal design method of the structural function of the present application decomposes the top-level function of the functional structure across disciplines through requirement analysis; based on the functional requirements, comprehensively consider the basic characteristics and technical feasibility of the existing materials, active cooling structure configuration, and manufacturing process, and carry out technical selection and demonstration under the structural geometric constraints; carry out the identification of the structural flow channel design parameters and the active cooling system design parameters, combine the experiments of key parameter components, analyze the influence laws of their effects on the structural heat transfer and heat exchange characteristics, summarize the key parameter groups of the integrated thermal design of the structural function, select the structural and active cooling system design parameters according to the action effects of the thermal parameters, and complete the design of the functional structure scheme; for the functional and performance requirements of practical applications, decompose the multi-dimensional and multi-level functional structure comprehensive evaluation index system, and carry out scheme evaluation and parameter optimization design according to the evaluation requirements; through the tests of typical parts under the simulated thermal conditions, test the functional performance of the functional structure, so as to obtain the functional structure that meets the design requirements.

[0051] The integrated thermal design method of the structural function of the present application can effectively solve the problem of the design of the active cooling functional structure integrating the disciplines of structure and thermal management, and it has the following advantages:

[0052] (1) In the technical demonstration stage, based on the functional requirements, it is recommended to comprehensively consider the basic characteristics of the existing materials, active cooling structure configuration, and manufacturing process, which can provide sufficient guidance for the technical feasibility demonstration and the improvement of design constraints;

[0053] (2) In the scheme design stage, it is recommended to identify and analyze the interaction effects of the structural flow path design parameters and the active cooling system design parameters. The key parameter group of the integrated thermal design of the structural function can effectively guide the design of the active cooling function structure;

[0054] (3) In the evaluation and optimization stage, it is recommended to construct a comprehensive evaluation index system from four multi-dimensions, which can provide effective reference for the optimized design of the active cooling function structure;

[0055] (4) The process is simple and clear, and the key design elements of each stage are clearly described. It is possible to identify the key design elements and implementation scheme design according to the specific requirements of the active cooling function structure, and quickly construct the functional structure model according to the technical process of this application.

[0056] For the above reasons, this application can be used to guide the design of structures and systems with active cooling functions, and can be widely promoted in local heat transfer fields with high heat flux density such as aviation, aerospace, and power energy.

[0057] The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in this application should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

1. A structural-functional integrated thermal design method, characterized in that, it includes: Step 1: Define the boundary of functional structure design through requirement analysis; Step 2: Based on the basic characteristics and technical feasibility of the material database, active cooling structure configuration database, and manufacturing process database, conduct technical selection and demonstration under the structural geometric constraint conditions; The material database includes a cooling medium performance database and a structural material performance database; The active cooling structure configuration database includes a straight channel database, a fractal channel database, and a topological channel database; The manufacturing process database includes an additive manufacturing database, a machining database, and a precision casting database; Step 3: Identify the structural channel design parameters and active cooling system design parameters, combine with key parameter element experiments, analyze the influence laws on the structural heat transfer and heat exchange characteristics, summarize the key parameter groups of the structural-functional integrated thermal design, and select the structural channel design parameters and active cooling system design parameters according to the action effects to complete the scheme design; Step 4: For the functional and performance requirements of practical applications, hierarchically decompose the functional structure comprehensive evaluation index system from multiple dimensions, and complete the scheme evaluation and parameter optimization design according to the evaluation requirements; Step 5: Complete the thermo-mechanical coupling test of the typical functional structure test piece under the simulated thermal conditions.

2. The structural-functional integrated thermal design method according to claim 1, characterized in that, in Step 1, the requirement analysis includes thermal protection requirement analysis, load-bearing requirement analysis, and reusable requirement analysis.

3. The structural-functional integrated thermal design method according to claim 1, characterized in that, in Step 3, the structural channel design parameters include channel cross-sectional size, channel cross-sectional shape, channel length, channel layout configuration, number of channels, channel spacing, and channel surface condition; the active cooling system design parameters include fluid type, flow state, flow rate, flow velocity, flow direction, fluid inlet and outlet, and driving pump power.

4. The structural-functional integrated thermal design method according to claim 3, characterized in that, the channel cross-sectional shape includes rectangle, triangle, trapezoid, and circle.

5. The structural-functional integrated thermal design method according to claim 1, characterized in that, in Step 4, hierarchically decompose the functional structure comprehensive evaluation index system from four dimensions of basic performance, comprehensive support performance, realizable performance, and compensatory performance.

6. The structural-functional integrated thermal design method according to claim 5, characterized in that, the basic performance includes load-bearing performance and heat protection performance; the comprehensive support performance includes reliability, reusability, maintainability, and safety; the realizable performance includes machining performance and assembly performance; the compensatory performance includes energy demand, compensatory loss, and economy.

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