A building-block type reconfigurable flutter model construction method and system

Abstract

This application belongs to the technical field of wind tunnel test, and specifically relates to a building-block type reconfigurable flutter model construction method and system. The method includes step S1, determining the design objectives and initial mathematical model of the horizontal tail flutter model; step S2, dividing the horizontal tail into multiple partition models, determining the number of partition models, as well as the area, position, and initial stiffness and weight parameters of each partition model; step S3, determining the variable parameter range and parameter combinations of each partition model with the achievement of the wind tunnel test objectives as the constraint; step S4, taking stiffness and mass as the optimization objectives, and individually optimizing each partition model; step S5, assembling each partition model to form a horizontal tail flutter model, and performing overall optimization with the flutter characteristics as the objective to obtain the structural design parameters of the flutter model; step S6, processing each partition model by additive manufacturing technology. This application uses additive manufacturing technology to quickly batch-copy each split model, greatly improving the processing efficiency and reducing the production cost.

Description

Technical Field

[0001] This application belongs to the technical field of wind tunnel tests, and particularly relates to a building-block type reconfigurable flutter model construction method and system. Background Art

[0002] Aeroelasticity is a mechanics discipline that studies the mechanical behavior of elastic objects in airflows, and its task is to study the mutual influence between aerodynamic forces and elastic bodies. In the process of studying aeroelasticity problems, as an essential part of the experimental verification link - the aeroelastic wind tunnel test plays an important role. Aeroelastic wind tunnel tests include flutter tests, buzz tests, gust response tests, buffet tests, and static aeroelasticity tests, etc., all of which are important means to study aeroelastic phenomena, and among them, the flutter wind tunnel test is the most widely used. The flutter wind tunnel test can be mainly divided into low-speed tests and transonic tests according to the wind tunnels used.

[0003] Due to the large size of the test section of low-speed wind tunnels, the model is subject to relatively small aerodynamic loads during the test, making the low-speed flutter model more convenient to design and manufacture compared to the transonic flutter model. At the same time, due to the low cost of low-speed wind tunnel tests, the low-speed flutter wind tunnel test is more suitable for parameter influence research. Traditional low-speed flutter models generally adopt a beam-frame model structure, that is, using metal beam frames to simulate the stiffness characteristics of the wing surface and wooden structural frames to simulate the aerodynamic shape of the wing surface. Although this traditional structural form of flutter model is simple in design and processing and has a low model cost, when a large number of variable parameter studies are required in wind tunnel tests, multiple models need to be designed and processed to complete different test tasks, thus increasing the total test cost and reducing the test efficiency. Therefore, it is necessary to design a low-cost and rapidly variable parameter flutter model for low-speed flutter wind tunnel tests. Summary of the Invention

[0004] To solve the above problems, this application provides a building-block type reconfigurable flutter model construction method and system, which applies mathematical optimization techniques to comprehensively optimize and calculate the main design parameters of each sub-model of the building-block type reconfigurable low-speed flutter model, and obtains specific design parameters.

[0005] The first aspect of this application provides a building-block type reconfigurable flutter model construction method, which mainly includes:

[0006] Step S1, determining the design objective and initial mathematical model of the horizontal tail flutter model;

[0007] Step S2, dividing the horizontal tail into multiple partition models, determining the number of partition models, as well as the area, position, initial stiffness, and initial weight parameters of each partition model;

[0008] Step S3: Determine the variable parameter ranges and parameter combinations of each partition model with the constraint of achieving the wind tunnel test objectives;

[0009] Step S4: Individually optimize each partition model with stiffness and mass as the optimization objectives;

[0010] Step S5: Assemble each partition model to form a horizontal tail flutter model, and conduct overall optimization with the flutter characteristics of the model as the objective to obtain the structural design parameters of the flutter model;

[0011] Step S6: Process each partition model by additive manufacturing technology.

[0012] Preferably, step S2 further includes:

[0013] Step S21: For each partition model, perform stiffness and weight simplification to obtain the initial structural dimensions of a single region.

[0014] Preferably, after step S21, it further includes:

[0015] Step S22: Modify the geometric position, dimensions, and target weight of the partition model until the design or processing requirements are met.

[0016] Preferably, in step S3, determining the variable parameter ranges includes:

[0017] Determine that the variable parameter range of stiffness is multiple values within 80% - 100% of the initial stiffness parameter;

[0018] Determine that the variable parameter range of weight is multiple values within 80% - 100% of the initial weight parameter.

[0019] The second aspect of the present application provides a modular reconfigurable flutter model construction system, mainly including:

[0020] A model construction module, used to determine the design objectives and initial mathematical model of the horizontal tail flutter model;

[0021] A partition module, used to divide the horizontal tail into multiple partition models, determine the number of partition models, as well as the area, position, and initial stiffness and initial weight parameters of each partition model;

[0022] A parameter range and combination given module, used to determine the variable parameter ranges and parameter combinations of each partition model with the constraint of achieving the wind tunnel test objectives;

[0023] A partition optimization module, used to individually optimize each partition model with stiffness and mass as the optimization objectives;

[0024] An overall optimization module is used to assemble each partition model to form a horizontal tail flutter model, and perform overall optimization with the flutter characteristics of the model as the goal to obtain the structural design parameters of the flutter model;

[0025] A partition processing module is used to process each partition model by additive manufacturing technology.

[0026] Preferably, the partition module includes:

[0027] An initialization unit is used to simplify the stiffness and weight for each partition model to obtain the initial structural dimensions of a single region.

[0028] Preferably, the partition module further includes:

[0029] A correction unit is used to modify the geometric position, dimensions, and target weight of the partition model until the design or processing requirements are met.

[0030] Preferably, the parameter range and combination giving module includes:

[0031] A stiffness parameter range giving unit is used to determine that the variable parameter range of stiffness is multiple values within 80% - 100% of the initial stiffness parameter;

[0032] A weight parameter range giving unit is used to determine that the variable parameter range of weight is multiple values within 80% - 100% of the initial weight parameter.

[0033] This application uses additive manufacturing technology to quickly batch copy each split model, greatly improving the processing efficiency and reducing the production cost. Description of the Drawings

[0034] Figure 1 It is a flowchart of a preferred embodiment of the building block type reconfigurable flutter model construction method of this application.

[0035] Figure 2 For this application Figure 1 Schematic diagram of the horizontal tail finite element model of the shown embodiment.

[0036] Figure 3 For this application Figure 1 Schematic diagram of the horizontal tail partition of the shown embodiment.

[0037] Figure 4 For this application Figure 1 Schematic diagram of the typical additive manufacturing technology split model of the shown embodiment. Detailed Embodiment

[0038] To make the objectives, technical solutions, and advantages of the present application more clear, the technical solutions in the embodiments of the present application will be described in more detail below in conjunction with the accompanying drawings in the embodiments of the present application. In the drawings, the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. The described embodiments are some, but not all, of the embodiments of the present application. The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present application and should not be construed as a limitation to the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts belong to the scope of protection of the present application. The embodiments of the present application will be described in detail below in conjunction with the accompanying drawings.

[0039] The first aspect of the present application provides a method for constructing a modular reconfigurable flutter model, as Figure 1 shown, mainly including:

[0040] Step S1: Determine the design objectives and initial mathematical model of the horizontal tail flutter model;

[0041] Step S2: Divide the horizontal tail into multiple partition models, determine the number of partition models, as well as the area, position, initial stiffness, and initial weight parameters of each partition model;

[0042] Step S3: Determine the variable parameter range and parameter combination of each partition model with the constraint of achieving the wind tunnel test objectives;

[0043] Step S4: Individually optimize each partition model with stiffness and mass as the optimization objectives;

[0044] Step S5: Assemble each partition model to form a horizontal tail flutter model, and perform overall optimization with the flutter characteristics of the model as the objective to obtain the structural design parameters of the flutter model;

[0045] Step S6: Process each partition model with additive manufacturing technology.

[0046] In some alternative embodiments, step S2 further includes:

[0047] Step S21: For each partition model, perform stiffness and weight simplification to obtain the initial structural dimensions of a single region.

[0048] In some alternative embodiments, after step S21, it further includes:

[0049] Step S22: Modify the geometric position, dimensions, and target weight of the partition model until the design or processing requirements are met.

[0050] In some alternative embodiments, in step S3, determining the variable parameter range includes:

[0051] Determining that the variable parameter range of the stiffness is multiple values within 80% to 100% of the initial stiffness parameter;

[0052] Determining that the variable parameter range of the weight is multiple values within 80% to 100% of the initial weight parameter.

[0053] In step S1 of the present application, determining the initial mathematical model means establishing an initial dynamic simplified model of the flutter model. In step S2, determining the split model means determining the split model to be designed for the wind tunnel test model through the analysis of the design inputs such as the flutter characteristics, dynamic characteristics, and structural layout of the physical model as the verification target, including the number, area, and position of the split models, etc. In step S3, determining the variable parameter range and the parameter combination relationship. Determine the achievable variable parameter range and parameter combination for the wind tunnel test according to the target of the wind tunnel test, the initial split model, and the mathematical model. In steps S4 and S5, determining the simulation mathematical model. Introduce mathematical optimization methods to optimize the structural parameters of each split model, and at the same time perform the structural design of the split model after variable parameters. If the structural design cannot meet the test requirements during this process, it is necessary to readjust the set initial mathematical model or variable parameter range. In step S6, processing and assembling the split models. Apply the additive manufacturing process to complete the batch manufacturing of each split model, and perform trial assembly on the model design state and each variable parameter combination state.

[0054] The main innovation of the present application is to apply mathematical optimization to the design of the modular and reconfigurable split models. Specifically, first, taking the mathematical model and the split model layout as inputs, optimize the stiffness and mass distribution of each single split model to obtain the initial structural design of each split model; then assemble the models, and then perform overall optimization with the flutter characteristics of the model as the target and finally obtain the structural design parameters of the flutter model.

[0055] Another innovation of the present application lies in applying the additive manufacturing process to batch manufacture each split model. Its significance lies in:

[0056] 1) The split additive manufacturing process simultaneously solves the current limitations on the overall size of the model due to equipment reasons and the impact of local variable parameters on the overall model;

[0057] 2) The additive manufacturing significantly improves the model processing efficiency and saves a large amount of fitter trimming work time;

[0058] 3) The additively manufactured models by batch manufacturing have good interchangeability, providing a basis for the modular and reconfigurable models.

[0059] Taking the low-speed flutter wind tunnel test model of a certain all-moving horizontal tail as an example, the design process of the model is as follows Figure 1 as shown

[0060] 1) Determine the design objectives and initial mathematical model of the horizontal tail flutter model. The finite element model is as follows Figure 2 as shown

[0061] 2) Divide the horizontal tail according to the flutter analysis results, structural layout and other design input conditions of the horizontal tail. In this example, the horizontal tail is divided into 12 areas as follows Figure 3 as shown. For each area, simplify the stiffness and weight to obtain the initial structural dimensions of a single area. If the initial dimensions do not meet the design or processing requirements, the plan shall be changed. The parameters that can be modified include the geometric position, dimensions, target weight, etc. of the split model until the initial design basically meets the requirements

[0062] 3) Plan the variable parameter range, initial parameters of the split parts and combinations, etc. according to the requirements of the test task book, such as 100%, 90%, 80% of the stiffness, 100%, 90%, 80% of the weight, etc. and the combination schemes of the above parameters

[0063] 4) Perform hierarchical optimization on the split model and the assembled horizontal tail dynamic model to obtain the final model structure parameters. If the structure cannot be realized, the partition scheme shall be adjusted and redesigned

[0064] 5) Process the model using additive manufacturing technology and perform trial assembly on each combined state of the model. The split models of typical additive manufacturing technology are as follows Figure 4 as shown

[0065] The second aspect of this application provides a building block type reconfigurable flutter model construction system corresponding to the above method, mainly including

[0066] A model construction module, used to determine the design objectives and initial mathematical model of the horizontal tail flutter model

[0067] A partition module, used to divide the horizontal tail into multiple partition models, determine the number of partition models, and the area, position, initial stiffness and initial weight parameters of each partition model

[0068] A parameter range and combination given module, used to determine the variable parameter range and parameter combination of each partition model with the realization of the wind tunnel test objective as a constraint

[0069] A partition optimization module, used to perform individual optimization on each partition model with stiffness and mass as the optimization objectives

[0070] The overall optimization module is used to assemble the partition models to form a horizontal tail flutter model, and perform overall optimization with the flutter characteristics of the model as the goal to obtain the structural design parameters of the flutter model;

[0071] The partition processing module is used to process each partition model by additive manufacturing technology.

[0072] In some alternative embodiments, the partition module includes:

[0073] The initialization unit is used to simplify the stiffness and weight for each partition model to obtain the initial structural dimensions of a single region.

[0074] In some alternative embodiments, the partition module further includes:

[0075] The correction unit is used to modify the geometric position, dimensions, and target weight of the partition model until the design or processing requirements are met.

[0076] In some alternative embodiments, the parameter range and combination given module includes:

[0077] The stiffness parameter range given unit is used to determine that the variable parameter range of stiffness is multiple values within 80% - 100% of the initial stiffness parameter;

[0078] The weight parameter range given unit is used to determine that the variable parameter range of weight is multiple values within 80% - 100% of the initial weight parameter.

[0079] Through this application, at the initial stage of model design, through reasonable planning and mathematical optimization of the verification target, key parameters such as the geometry, stiffness, and weight of the split model samples can be obtained, and the split models can be mass - replicated by additive manufacturing technology. Finally, a reliable flutter model with a large - range and rapid variable parameters can be provided in the wind tunnel test. The application method of the present invention is simple and easy to implement, and can provide a large number of variable - parameter flutter wind tunnel test model split models at a low cost. Through the modular combination and reconstruction, variable - parameter research in the wind tunnel test can be achieved, and the test efficiency, the subsequent design and analysis accuracy, and the cost - effectiveness ratio of the test can be improved.

[0080] Although the present application has been described in detail above with general descriptions and specific implementation examples, based on the present application, some modifications or improvements can be made, which are obvious to those skilled in the art. Therefore, these modifications or improvements made without departing from the spirit of the present application all fall within the scope of protection required by the present application.

Claims

1. A building-block type reconfigurable flutter model construction method, characterized in that Including: Step S1: Determine the design objectives and initial mathematical model of the horizontal tail flutter model; Step S2: Divide the horizontal tail into multiple partition models, determine the number of partition models, as well as the area, position, initial stiffness, and initial weight parameters of each partition model; Step S3: With the goal of realizing the wind tunnel test as a constraint, determine the variable parameter range and parameter combination of each partition model; Step S4: With stiffness and mass as the optimization objectives, perform separate optimization on each partition model; Step S5: Assemble each partition model to form a horizontal tail flutter model, perform overall optimization with the flutter characteristics of the model as the goal, and obtain the structural design parameters of the flutter model. If the structural design fails to meet the test requirements, readjust the set initial mathematical model or variable parameter range; Step S6: Process each partition model by additive manufacturing technology to provide multiple variable-parameter flutter wind tunnel test model sub-models, and reconstruct the flutter model through modular combination; Among them, in step S3, determining the variable parameter range includes: Determine that the variable parameter range of stiffness is multiple values within 80% - 100% of the initial stiffness parameter; Determine that the variable parameter range of weight is multiple values within 80% - 100% of the initial weight parameter.

2. The building block type reconfigurable flutter model construction method according to claim 1, characterized in that, Step S2 further includes: Step S21: For each partition model, perform stiffness and weight simplification to obtain the initial structural dimensions of a single area.

3. The building block type reconfigurable flutter model construction method according to claim 2, characterized in that, After step S21, it further includes: Step S22: Modify the geometric position, size, and target weight of the partition model until the design or processing requirements are met.

4. A modular reconfigurable flutter model construction system, characterized in that, Including: Model construction module, used to determine the design objectives and initial mathematical model of the horizontal tail flutter model; Partition module, used to divide the horizontal tail into multiple partition models, determine the number of partition models, as well as the area, position, initial stiffness, and initial weight parameters of each partition model; Parameter range and combination setting module, used to determine the variable parameter range and parameter combination of each partition model with the goal of realizing the wind tunnel test as a constraint; Partition optimization module, used to perform separate optimization on each partition model with stiffness and mass as the optimization objectives; Overall optimization module, used to assemble each partition model to form a horizontal tail flutter model, perform overall optimization with the flutter characteristics of the model as the goal, and obtain the structural design parameters of the flutter model. If the structural design fails to meet the test requirements, readjust the set initial mathematical model or variable parameter range; Partition processing module, used to process each partition model by additive manufacturing technology to provide multiple variable-parameter flutter wind tunnel test model sub-models, and reconstruct the flutter model through modular combination; The parameter range and combination setting module includes: Stiffness parameter range setting unit, used to determine that the variable parameter range of stiffness is multiple values within 80% - 100% of the initial stiffness parameter; Weight parameter range setting unit, used to determine that the variable parameter range of weight is multiple values within 80% - 100% of the initial weight parameter.

5. The modular reconfigurable flutter model building system according to claim 4, wherein The partition module includes: Initialization unit, used to perform stiffness and weight simplification for each partition model to obtain the initial structural dimensions of a single area.

6. The modular reconfigurable flutter model construction system according to claim 5, characterized in that The partition module further includes: A correction unit for modifying the geometric position, dimensions, and target weight of the partition model until the design or processing requirements are met.

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