Static aeroelastic force measurement wind tunnel test model of large flexible wing structure

Abstract

The utility model relates to a static aeroelastic force-measuring wind tunnel test model for a large-flexibility wing structure, which has the capability of testing the bending moment of a wing root and belongs to the technical field of aeroelastic tests of aircrafts. A static aeroelastic force measurement wind tunnel test model of a large flexible wing structure comprises a wing body fusion section, an outer wing section and a winglet, the wing body fusion section is arranged between the outer wing section and the winglet, the outer wing section comprises a wing section, an aileron, a spar and a steering engine, and the wing section is made of foam; the spar is bonded with the wing section, the length direction is consistent with that of the wing section, one end of the spar is connected with the winglet, and the other end of the spar extends out of the end part of the wing section to serve as a mounting end fixed with the side wall of the wind tunnel; the steering engine is connected with one side of the spar; the aileron serves as a part of the wing section, is bonded to the other side of the steering engine and can rotate along with actuation of the steering engine. The utility model has the advantages that: 1, the structural form is simple; 2, the assembly is simple, and the price is low; 3, the overall bearing load of the foam is reduced; and 4, the operation is easy.

Description

Technical Field

[0001] The utility model relates to a static aeroelastic force measurement wind tunnel test model of a large flexible wing structure, which can be equipped with a wing root bending moment test capability and belongs to the technical field of aircraft aeroelasticity test. Background Art

[0002] Under the performance requirements of long flight time and low weight, more and more modern aircraft adopt the design of large flexible wings. For the static aeroelastic deformation of large flexible wings, conducting wind tunnel tests is one of the important ways to study static aeroelasticity. In actual flight, under the action of aerodynamic loads, large flexible wings will produce obvious structural deformation, and the structural deformation will lead to the redistribution of aerodynamic loads, thus forming a complex coupling relationship. Determining the wing root bending moment under different flight conditions is of great significance for structural design.

[0003] Traditional aeroelastic wind tunnel test models require the use of a balance for testing. In theory, they do not have the ability to test the wing root bending moment. They have limited guiding role in structural design, and require high test accuracy for wind tunnel equipment. The interference to the model is also difficult to predict. The existing aeroelastic wind tunnel test wing model measures the pressure distribution of the corresponding wing section through pressure measuring tubes arranged in several pressure measuring wing ribs. It only reflects the local aerodynamic changes and cannot deduce the overall force of the wing. The model design and processing costs are high. In addition, the traditional wing model uses high-strength alloy steel with a large elastic modulus (about 200Gpa) and large bending stiffness, which makes it difficult to simulate the cumulative change of deflection along the span of a large flexible wing.

[0004] By measuring the wing root bending moment value of the large flexible wing structure, the load basis for structural design and optimization can be obtained, which is of great significance for studying aeroelasticity-related issues. The existing static aeroelastic force wind tunnel test model cannot measure the wing root bending moment when the wing undergoes static aeroelastic deformation. Utility Model Content

[0005] The utility model aims to provide a static aeroelastic force measurement wind tunnel test model of a large flexible wing structure, which can have the test capability of the wing root bending moment.

[0006] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a static aeroelastic force measurement wind tunnel test model of a large flexible wing structure, which includes a wing-body fusion section, an outer wing section and a winglet, the wing-body fusion section is arranged between the outer wing section and the winglet, the outer wing section includes a wing section, an aileron, a spar and a servo, and the material used for the wing section is foam; the spar is bonded to the wing section, and the length direction is consistent with the length direction of the wing section, one end of the spar is connected to the winglet, and the other end extends out of the end of the wing section as a mounting end fixed to the side wall of the wind tunnel; the servo is connected to one side of the spar; the aileron, as a part of the wing section, is bonded to the other side of the servo and can rotate with the actuation of the servo.

[0007] Preferably, the wing segment includes three segments distributed along its length direction and having the same appearance. Reinforcing ribs are arranged between adjacent wing segments, and the reinforcing ribs are bonded to the wing segments.

[0008] Preferably, the servo is arranged on the middle wing section, and the aileron is a part of the middle wing section.

[0009] Preferably, the wing spar is a single aluminum alloy beam.

[0010] Preferably, a strain gauge is attached to the root of the test model, the strain gauge is connected to a computer via a strain gauge, and the reading of the strain gauge is displayed on a computer screen in real time via software, which facilitates data collection and processing.

[0011] Preferably, the material used for the wing section is EPP foam (expanded polypropylene).

[0012] Compared with the prior art, the utility model has the following advantages:

[0013] 1. A single aluminum alloy beam is used to effectively simulate the stiffness characteristics of a large flexible wing, and the structure is simple;

[0014] 2. The wing section is made of EPP foam (expanded polypropylene), which has good aerodynamic shape effect, is easy to produce and process, simple to assemble, and low in price; the EPP foam material has little additional stiffness to the beam, and has good bearing capacity for distributed loads, which is very suitable for the shape simulation of the elastic model of the large flexible wing;

[0015] 3. According to the wing airfoil, several reinforcing ribs are designed and processed. The reinforcing ribs can effectively transfer the aerodynamic load on the wing surface to the beam in sections, reducing the overall load of the foam;

[0016] 4. The principle is simple, the requirements for the test environment are not high, the error is smaller than other indirect measurement methods, and it is easy to operate;

[0017] 5. The wing root bending moment load under static aeroelastic deformation can be obtained by measuring strain, providing important load data reference for structural design and optimization. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a perspective view of the structure of an embodiment of the utility model;

[0019] Figure 2 The pneumatic appearance diagram of the embodiment of the utility model;

[0020] Figure 1-2 In the figure, 1. wingtip winglet; 2. aileron; 3. wing beam; 4. reinforcing rib; 5. wing section; 6. servo; 7. strain gauge pasting position; 8. wing-body fusion section; 9. outer wing section. DETAILED DESCRIPTION

[0021] It should be noted that, in this embodiment, the terms "left", "right", "middle", etc. are described according to the drawings or the common usage of this embodiment, and do not constitute limitations to the present utility model.

[0022] The following is combined with Figure 1-2 The utility model is further described in detail: a static aeroelastic force measurement wind tunnel test model of a large flexible wing structure, such as Figure 2 As shown, the model consists of three parts: a wing-body fusion section 8, an outer wing section 9 and a winglet 1. The wing-body fusion section 8 is arranged between the outer wing section 9 and the winglet 1, and has a complete aerodynamic shape and force transmission structure.

[0023] like Figure 1 As shown, the outer wing section 8 includes a wing section, an aileron 2, a spar 3 and a steering gear 6. The material used for the wing section is EPP foam; the spar 3 is bonded to the wing section by organic glue, and its length direction is consistent with the length direction of the wing section, one end of the spar is connected to the winglet 1 by screws, and the other end extends out of the end of the wing section as a mounting end fixed to the side wall of the wind tunnel; the steering gear 6 is connected to one side of the spar 3; the aileron 2, as a part of the wing section, is bonded to the other side of the steering gear 6 by organic glue, and can rotate with the actuation of the steering gear 6.

[0024] As a preferred implementation of this embodiment, the wing section includes three sections, namely the left, middle and right sections. Each section adopts integral EPP foam (foamed polypropylene). The three sections are arranged in sequence along their length direction and have the same appearance. Reinforcing ribs 4 are set between adjacent wing sections, and the reinforcing ribs 4 are bonded to the wing sections.

[0025] As a preferred implementation of this embodiment, the servo 6 is arranged on the middle wing section, and the aileron 2 is a part of the middle wing section.

[0026] As a preferred implementation of this embodiment, the spar 3 is a single aluminum alloy beam.

[0027] As a preferred implementation of this embodiment, a strain gauge pasting position 7 is set at the root of the test model (i.e., the left end of the wing section 5) for pasting the strain gauge. The strain gauge is connected to the computer through a strain gauge, and the reading of the strain gauge is displayed on the computer screen in real time through software, which is convenient for data collection and processing. The wing root bending moment load is calculated based on the relationship between the wing root bending moment and the strain gauge reading.

[0028] In this embodiment, the airfoil adopts the low-speed airfoil MH32, which is suitable for low-speed long-flight aircraft and has good aerodynamic characteristics. Taking a certain state as an example, given an angle of attack α = 2.0°, Mach number Ma = 0.6, at a given angle of attack and wind speed, the wing root bending moment load is converted according to the strain reading of the strain gauge, as shown in formula (1):

[0029] Mmax =E×ε×W (1)

[0030] in:

[0031] M max is the maximum wing root bending moment, i.e. the required wing root bending moment load;

[0032] E is the Young’s modulus of the wing spar;

[0033] ε is the strain reading of the strain gauge;

[0034] W is the cross-sectional bending coefficient of the wing.

[0035] Firstly, the static aeroelastic analysis of the model is carried out by numerical method using static aeroelastic balance analysis method, that is, firstly the aerodynamic load distribution on the wing in the undeformed state is calculated, then the deformation of the wing is calculated according to the aerodynamic load distribution, and then the aerodynamic load on the deformed wing is calculated, and the iteration is repeated until convergence. L =0.504795, at this time the relative deformation of the wing tip is 0. After the calculation results converge, the C L =0.477232, and the relative deformation of the wing tip is 14.09%. The above results show that the designed model has a good verification effect on the static aeroelastic deformation, and can also be used for experimental research related to the static aeroelastic phenomenon.

[0036] The above embodiments are only preferred implementations of the present invention and do not constitute limitations on the present invention. Any extensions and modifications made by ordinary technicians in this field without departing from the principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A static aeroelastic force wind tunnel test model of a large flexible wing structure, comprising a wing-body fusion section, an outer wing section and a winglet, wherein the wing-body fusion section is arranged between the outer wing section and the winglet, and is characterized in that: The outer wing section includes the wing section, aileron, spar and servo. The material used for the wing section is foam; the spar is bonded to the wing section, and its length direction is consistent with the length direction of the wing section. One end of the spar is connected to the wingtip winglet, and the other end extends out of the end of the wing section as a mounting end fixed to the side wall of the wind tunnel; the servo is connected to one side of the spar; the aileron, as a part of the wing section, is bonded to the other side of the servo and can rotate with the actuation of the servo.

2. The static aeroelastic force wind tunnel test model of a large flexible wing structure according to claim 1, characterized in that: The wing section includes three sections, which are distributed along the length direction and have the same appearance. Reinforcement ribs are arranged between adjacent wing sections, and the reinforcement ribs are bonded to the wing sections.

3. The static aeroelastic force wind tunnel test model of a large flexible wing structure according to claim 2, characterized in that: The servo is arranged on the middle wing section, and the aileron is a part of the middle wing section.

4. The static aeroelastic force wind tunnel test model of a large flexible wing structure according to claim 1 or 2, characterized in that: The wing spar adopts a single aluminum alloy beam.

5. The static aeroelastic force wind tunnel test model of a large flexible wing structure according to claim 1 or 2, characterized in that: A strain gauge is pasted at the root of the test model, and the strain gauge is connected to a computer through a strain meter. The reading of the strain meter is displayed on a computer screen in real time through software, which is convenient for data collection and processing.

6. The static aeroelastic force wind tunnel test model of a large flexible wing structure according to claim 1, characterized in that: The material used for the wing section is EPP foam.

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