Moving airfoil variable stiffness test fixture and design method thereof

Abstract

The invention provides a moving airfoil variable stiffness test fixture and a design method thereof. The test fixture comprises a bearing terrace and at least one set of supporting assembly, wherein the supporting assembly comprises a bearing frame, a hinge support, a spring plate, a limiting block, a lug support, an elastic screw sleeve and an adapter; the force bearing frame comprises a horizontal part and a vertical part and is installed on the force bearing terrace. The two hinged supports are connected to the horizontal part and the vertical part of the force bearing frame correspondingly. The spring plate comprises a first spring plate and a second spring plate which are respectively connected with the two hinged supports; the limiting blocks comprise the first limiting block and the second limiting block which are arranged on the horizontal part and the vertical part of the force bearing frame correspondingly. The lug supports comprise the first lug support and the second lug support which are arranged at the end of the first spring plate and the end of the second spring plate respectively. The elastic thread sleeve is installed on the first lug support, and the adapter connector is connected with the second lug support, the elastic thread sleeve and one moving wing surface connector of the moving wing surfaces.

Description

Technical Field

[0001] The present application belongs to the technical field of aircraft strength testing, and in particular relates to a moving wing surface variable stiffness test fixture and a design method thereof. Background Art

[0002] The moving wing surface fatigue test is one of the important contents of the aircraft structure verification test. Before the fatigue test, the moving wing surface needs to be fixed by a support fixture. As a hyperstatic structure, the load distribution of the moving wing surface at the joint connected to the wing is affected by the wing support stiffness. In the moving wing surface fatigue test, if the influence of the support stiffness of the joints between the moving wing surface and the wing is considered, the moving wing surface needs to be connected to the real wing, resulting in a great waste of test resources. However, the traditional moving wing surface test fixture cannot provide the real wing support stiffness. Therefore, a moving wing surface test fixture that can simulate the wing support stiffness is needed to provide real support conditions for the moving wing surface fatigue test. Summary of the invention

[0003] The purpose of the present application is to provide a moving airfoil variable stiffness test fixture and a design method thereof to solve or alleviate at least one problem in the background technology.

[0004] The technical solution of the present application is: a moving wing surface variable stiffness test fixture, comprising: a load-bearing floor and at least one set of supporting components including a load-bearing frame, a hinged support, a spring plate, a limit block, an ear support, a tightening screw sleeve, and an adapter joint; The load-bearing frame includes a horizontal part and a vertical part, which is installed on the load-bearing floor; The hinged support includes a first hinged support and a second hinged support, wherein the first hinged support is connected to the horizontal portion of the load-bearing frame, and the second hinged support is connected to the vertical portion of the load-bearing frame; The spring plate comprises a first spring plate and a second spring plate, the first spring plate is connected to the first hinge support, and the second spring plate is connected to the second hinge support; The limit block includes a first limit block and a second limit block, wherein the first limit block is arranged on the horizontal portion of the load-bearing frame and located on the inner side of the first hinge support, and is used to clamp the first spring plate, and the second limit block is arranged on the vertical portion of the load-bearing frame and located on the outer side of the second hinge support, and is used to clamp the second spring plate; The ear support includes a first ear support and a second ear support, wherein the first ear support is arranged at the inner end of the first spring plate, and the second ear support is arranged at the outer end of the second spring plate; The turnbuckle is installed on the first ear support, and the adapter joint is respectively connected to the second ear support, the turnbuckle and one of the moving wing surface joints of the moving wing surface.

[0005] In a preferred embodiment of the present application, the number of the support assemblies is the same as the number of the moving wing surface joints of the moving wing surface, and a plurality of the support assemblies are arranged in parallel along the span direction of the moving wing surface and are respectively connected to the moving wing surface joints to support the moving wing surface.

[0006] In a preferred embodiment of the present application, the cross-section of the spring plate is rectangular.

[0007] In a preferred embodiment of the present application, the limit block includes an upper limit block and a lower limit block, and the upper limit block and the lower limit block are connected by bolts.

[0008] In a preferred embodiment of the present application, the contact surfaces between the upper limit block, the lower limit block and the corresponding spring plates are semicircular curved surfaces.

[0009] In a preferred embodiment of the present application, the tensioning screw sleeve includes an upper ear piece, a middle connecting tube and a lower ear piece, the lower ear piece is connected to the first ear piece support, the upper ear piece is connected to the adapter joint, the upper ear piece and the lower ear piece are respectively connected to the two ends of the middle connecting tube through a threaded structure, and the length of the tensioning screw sleeve can be adjusted by screwing the middle connecting tube.

[0010] In a preferred embodiment of the present application, the adapter joint is a triangular structure, and a first ear, a second ear and a third ear are provided at the three vertices of the triangular structure, the first ear is connected to the upper ear of the tightening nut, the second ear is connected to the second ear support, and the third ear is connected to the moving wing joint.

[0011] On the other hand, the technical solution provided by the present application is: a design method of a moving wing surface variable stiffness test fixture as described above, comprising: Step 1: Obtain the actual support stiffness of the connection between the moving wing surface and the wing; Decompose the true support stiffness of the connection between the moving surface and the wing into the true vertical stiffness , true horizontal stiffness and the true lateral stiffness , where the true lateral stiffness of the connection is not considered ; In the wing finite element model, vertical loads are applied separately at the connection between the moving surface and the wing. and horizontal load , respectively, under the vertical load Vertical displacement below and horizontal load Horizontal displacement under , calculate the true vertical stiffness and the true horizontal stiffness ; Step 2: Calculate the simulated support stiffness of the spring plate and determine the design parameters of the spring plate; The simulated support stiffness of the spring plate is achieved by designing the deformation of the end of the spring plate, where the first spring plate is used to simulate the vertical stiffness , the second spring plate is used to simulate the horizontal stiffness , calculate and simulate the vertical stiffness and simulated horizontal stiffness ; The elastic modulus is determined by selecting the material of the spring plate, and then the design parameters of the spring plate are adjusted to make , , thereby obtaining the design parameters of the spring plate, the design parameters including the width of the spring plate b ,thickness h And the distance between the ear support and the limit block a , the distance between the limit block and the hinged support l ; Step 3: Repeat steps 1 and 2 to obtain the design parameters of the spring plate used to simulate each connection point between the moving wing surface and the wing, and make N sets of support assemblies according to the design parameters. Arrange the N sets of support assemblies in parallel along the span direction of the moving wing surface and connect them to the moving wing surface.

[0012] In a preferred embodiment of the present application, the true vertical stiffness and the true horizontal stiffness The calculation method is: , .

[0013] In a preferred embodiment of the present application, the simulated vertical stiffness and simulated horizontal stiffness The calculation method is: , ; In the formula, E is the elastic modulus of the spring plate, b is the width of the spring plate, h is the thickness of the spring plate, a is the distance between the ear support and the limit block, l It is the distance between the limit block and the hinged support.

[0014] The variable stiffness test fixture for moving wing surfaces and the design method thereof provided in the present application achieve support stiffness simulation at each joint of the moving wing surface by designing the elastic deformation of the spring plate. The principle is clear, the test fixture structure is simple and reliable, and the test piece can be installed conveniently and quickly. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solution provided by the present application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present application.

[0016] Figure 1 This is a schematic diagram of the test fixture structure of this application.

[0017] Figure 2 This is a diagram of the limit block structure of this application.

[0018] Figure 3 This is a cross-sectional view of the relationship between the spring plate and the upper and lower limit blocks of this application.

[0019] Figure 4 This is an assembly diagram of the tightening screw sleeve of this application.

[0020] Figure 5 This is a schematic diagram of the adapter connector of this application.

[0021] Figure 6 This is a schematic diagram of the moving wing of this application.

[0022] Figure 7 This is a schematic diagram of the connection status between the moving wing surface and the wing of the present application.

[0023] Figure 8 This is a schematic diagram of the wing finite element model of this application.

[0024] Fig. 9 This is a schematic diagram of the design parameters of this application.

[0025] Fig.10 This is the assembly diagram of the moving wing surface and test fixture for this application.

[0026] Reference numerals: 1-Bearing floor 2-Load-bearing frame 3-First hinged support 4-First spring plate 5-First limit block 51-Upper limit block 52-Lower limit block 53-semicircular surface 6-First ear support 7-Tightening screw 71-Upper ear piece 72-Middle connecting tube 73-Lower ear piece 8-Adapter 81-First ear 82-Second ear 83-Third ear 9-Second ear support 10-Second spring plate 11- Second limit block 12- Second hinged support 13-Sports wing 131-Sports wing joint 14-Wing 15-Wing finite element model 151-Wing joint DETAILED DESCRIPTION

[0027] In order 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 in conjunction with the drawings in the embodiments of this application.

[0028] In order to solve the problem that the traditional moving wing surface test fixture cannot provide the real wing support stiffness, the present application provides a moving wing surface variable stiffness test fixture and a design method thereof.

[0029] like Figure 1 As shown, the variable stiffness test fixture of the moving wing surface provided by the present application includes a load-bearing floor 1 and at least one set of support components including a load-bearing frame 2, a hinged support, a spring plate, a limit block, an ear support, a turnbuckle 7 and an adapter joint 8. The number of the support components is the same as the number of joints of the moving wing surface 13.

[0030] This application is described using a set of support components as an example.

[0031] The load-bearing frame 2 is L-shaped as a whole, and includes a horizontal portion and a vertical portion. The load-bearing frame 2 is installed on the load-bearing floor 1 .

[0032] The articulated support includes a first articulated support 3 and a second articulated support 12 . The first articulated support 3 is connected to the horizontal portion of the load-bearing frame 2 , and the second articulated support 12 is connected to the vertical portion of the load-bearing frame 2 .

[0033] The spring plate comprises a first spring plate 4 and a second spring plate 10 , wherein the first spring plate 4 is connected to the first hinge support 3 , and the second spring plate 10 is connected to the second hinge support 12 , wherein the first spring plate 4 and the second spring plate 10 are both rectangular in cross-section.

[0034] The limit block includes a first limit block 5 and a second limit block 11. The first limit block 5 is connected to the horizontal part of the load-bearing frame 2 and is arranged on the inner side of the first hinged support 3 (i.e., the side close to the vertical part of the load-bearing frame 2), and the second limit block 11 is connected to the vertical part of the load-bearing frame 2 and is arranged on the outer side of the second hinged support 12 (i.e., away from the horizontal part of the load-bearing frame 2).

[0035] like Figure 2As shown, the first limit block 5 includes an upper limit block 51 and a lower limit block 52, and the upper limit block 51 and the lower limit block 52 are connected by bolts.

[0036] like Figure 3 As shown, the first spring plate 4 is clamped between the upper and lower limit blocks of the first limit block 5, and the second spring plate 10 is clamped between the upper and lower limit blocks of the second limit block 11. In order to ensure the simply supported constraint condition of the upper and lower limit blocks clamping the first spring plate 4, the contact surface between the upper and lower limit blocks and the first spring plate 4 is set to a semicircular curved surface 53.

[0037] The ear support includes a first ear support 6 and a second ear support 9. The first ear support 6 is arranged at the inner end of the first spring plate 4 for connecting the tensioning screw sleeve 7. The second ear support 9 is arranged at the outer end of the second spring plate 10 for connecting the adapter joint 8.

[0038] It should be noted that, in the above embodiments of the present application, the first spring plate 4 and the second spring plate 10, the first limit block 5 and the second limit block 11, and the first ear support 6 and the second ear support 9 are all of the same or similar structures, and the above embodiments of the present application are described with reference to any spring plate, limit block or ear support.

[0039] like Figure 4 As shown, the tensioning screw sleeve 7 includes an upper ear piece 71, a middle connecting tube 72 and a lower ear piece 73. The lower ear piece 73 is connected to the first ear piece support 6, and the upper ear piece 71 is connected to the adapter joint 8. The upper ear piece 71 and the lower ear piece 73 are respectively connected to the two ends of the middle connecting tube 72 through a threaded structure. The length of the tensioning screw sleeve 7 can be adjusted by screwing the middle connecting tube 72.

[0040] like Figure 5 As shown, the adapter joint 8 is a triangular structure as a whole, which includes a first ear piece 81, a second ear piece 82 and a third ear piece 83 which are roughly located at the three vertices of the triangle. The first ear piece 81 is connected to the upper ear piece 71 of the tightening nut 7, the second ear piece 82 is connected to the second ear piece support 9, and the third ear piece 83 is connected to the moving wing surface joint 131.

[0041] like Figure 6 The figure shows a certain type of moving wing surface 13 in this embodiment of the present application. The moving wing surface 13 has a total of 5 moving wing surface joints 131 along the span direction, namely, moving wing surface joints 131A to moving wing surface joints 131E. Figure 7 It is a schematic diagram of the connection state of the moving wing surface 13 and the wing 14, where the five moving wing surface joints 131 of the moving wing surface 13 are connected to the five wing joints 151 of the wing finite element model 15 in a one-to-one correspondence.

[0042] To this end, the present application also provides a design method for the above-mentioned moving wing surface variable stiffness test fixture, including the following process: Step 1: Extract the real support stiffness of the connection between the moving wing surface 13 and the wing 14: The real support stiffness of the connection between the moving wing surface 13 and the wing 14 is decomposed into the real vertical stiffness , true horizontal stiffness and the true lateral stiffness It is generally believed that the connection between the moving wing and the wing mainly bears horizontal and vertical loads, so the actual lateral stiffness of the connection is generally not considered. .

[0043] like Figure 8 In the wing finite element model 15 shown, vertical loads and horizontal loads are applied separately at the wing joints 151A to 151E, and the vertical displacement δ1 of each joint under the vertical load P1 and the horizontal displacement δ2 under the horizontal load P2 are calculated respectively, and the true vertical stiffness and the true horizontal stiffness are calculated according to the following formula: , ; The calculation results are shown in Table 1: Table 1 Actual support stiffness of each wing joint

[0044] Step 2: Calculate the simulated support stiffness of the spring plate and determine the design parameters of the spring plate: The simulated support stiffness of the spring plate is achieved by designing the deformation of the end of the spring plate, wherein the first spring plate 4 is used to simulate the vertical stiffness The second spring plate 10 is used to simulate the horizontal stiffness , the simulated stiffness of the above spring plate (Vertical and horizontal) are calculated according to the following formula: In the formula, E is the elastic modulus of the spring plate, b is the width of the spring plate, h is the thickness of the spring plate, a is the distance between the ear support and the limit block, l is the distance between the limit block and the hinged support, and the parameters are as follows Fig. 9 shown.

[0045] Determine the material and elastic modulus of the spring plate. In this embodiment of the present application, the material of the spring plate is aluminum alloy with an elastic modulus of E=70000MPa. Then adjust the width of the spring plate. b ,thickness h And the distance between the ear support and the limit block a, the distance between the limit block and the hinged support l The design parameters make , , thus obtaining the design parameters of the spring plate. The calculation results of the spring plate are shown in Table 2: Table 2 Simulated support stiffness of each wing joint

[0046] Step 3: Design multiple sets of support components according to the number of the moving wing surface joints 131 . The multiple sets of support components are arranged in parallel along the span direction of the moving wing surface 13 and connected to the joints of the moving wing surface 13 .

[0047] like Fig.10 In the illustrated embodiment, the moving wing surface 13 has five joints. The design parameters of the spring plates in the five sets of support assemblies are obtained according to the above steps. The five sets of support assemblies are arranged in parallel along the span direction of the moving wing surface 13 and connected to the five joints of the moving wing surface 13 to support the moving wing surface 13.

[0048] The variable stiffness test fixture for moving wing surfaces and the design method thereof provided in the present application achieve support stiffness simulation at each joint of the moving wing surface by designing the elastic deformation of the spring plate. The principle is clear, the test fixture structure is simple and reliable, and the test piece can be installed conveniently and quickly.

[0049] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A variable stiffness test fixture for a moving wing surface, characterized in that: include: A load-bearing floor (1) and at least one set of supporting components including a load-bearing frame (2), a hinged support, a spring plate, a limit block, an ear support, a tightening screw sleeve (7), and an adapter joint (8); The load-bearing frame (2) comprises a horizontal portion and a vertical portion, and is installed on the load-bearing floor (1); The articulated support comprises a first articulated support (3) and a second articulated support (12), wherein the first articulated support (3) is connected to a horizontal portion of the load-bearing frame (2), and the second articulated support (12) is connected to a vertical portion of the load-bearing frame (2); The spring plate comprises a first spring plate (4) and a second spring plate (10), the first spring plate (4) being connected to a first hinged support (3), and the second spring plate (10) being connected to a second hinged support (12); The limit block comprises a first limit block (5) and a second limit block (11); the first limit block (5) is arranged on the horizontal portion of the load-bearing frame (2) and is located on the inner side of the first hinged support (3), and is used to clamp the first spring plate (4); the second limit block (11) is arranged on the vertical portion of the load-bearing frame (2) and is located on the outer side of the second hinged support (12), and is used to clamp the second spring plate (10); The ear piece support comprises a first ear piece support (6) and a second ear piece support (9), the first ear piece support (6) being arranged at the inner end of the first spring plate (4), and the second ear piece support (9) being arranged at the outer end of the second spring plate (10); The tensioning screw sleeve (7) is mounted on the first ear support (6), and the adapter joint (8) is respectively connected to the second ear support (9), the tensioning screw sleeve (7) and a moving wing surface joint (131) of the moving wing surface (13).

2. The variable stiffness test fixture for a moving wing surface as claimed in claim 1, characterized in that: The number of the support assemblies is the same as the number of the moving wing surface joints (131) of the moving wing surface (13); a plurality of the support assemblies are arranged in parallel along the span direction of the moving wing surface (13) and are respectively connected to the moving wing surface joints (131) to achieve support for the moving wing surface.

3. The variable stiffness test fixture for a moving wing surface as claimed in claim 1, characterized in that: The cross section of the spring plate is rectangular.

4. The variable stiffness test fixture for moving wing surface according to claim 1, characterized in that: The limit block comprises an upper limit block (51) and a lower limit block (52), and the upper limit block (51) and the lower limit block (52) are connected by bolts.

5. The moving wing surface variable stiffness test fixture according to claim 4, characterized in that: The contact surfaces between the upper limit block (51), the lower limit block (52) and the corresponding spring plates are semicircular curved surfaces (53).

6. The variable stiffness test fixture for a moving wing surface as claimed in claim 1, characterized in that: The tensioning screw sleeve (7) comprises an upper ear piece (71), a middle connecting tube (72) and a lower ear piece (73); the lower ear piece (73) is connected to a first ear piece support (6); the upper ear piece (71) is connected to an adapter joint (8); the upper ear piece (71) and the lower ear piece (73) are respectively connected to two ends of the middle connecting tube (72) via a threaded structure; and the length of the tensioning screw sleeve (7) can be adjusted by screwing the middle connecting tube (72).

7. The variable stiffness test fixture for a moving wing surface as claimed in claim 5, characterized in that: The adapter joint (8) is a triangular structure, and a first ear piece (81), a second ear piece (82) and a third ear piece (83) are provided at three vertices of the triangular structure, the first ear piece (81) is connected to the upper ear piece (71) of the turnbuckle (7), the second ear piece (82) is connected to the second ear piece support (9), and the third ear piece (83) is connected to the moving wing surface joint (131).

8. A method for designing a moving wing surface variable stiffness test fixture as claimed in any one of claims 1 to 6, characterized in that: include: Step 1, obtaining the actual support stiffness of the connection between the moving wing surface (13) and the wing (14); The real support stiffness of the connection between the moving wing surface (13) and the wing (14) is decomposed into the real vertical stiffness , true horizontal stiffness and the true lateral stiffness , where the true lateral stiffness of the connection is not considered ; In the wing finite element model (15), a vertical load is applied separately at the connection between the moving airfoil (13) and the wing. and horizontal load , respectively, under the vertical load The vertical displacement of and horizontal load Horizontal displacement under , calculate the true vertical stiffness and true horizontal stiffness ; Step 2: Calculate the simulated support stiffness of the spring plate and determine the design parameters of the spring plate; The simulated support stiffness of the spring plate is achieved by designing the deformation of the end of the spring plate, wherein the first spring plate (4) is used to simulate the vertical stiffness. The second spring plate (10) is used to simulate the horizontal stiffness , calculate and simulate the vertical stiffness and simulated horizontal stiffness ; The elastic modulus is determined by selecting the material of the spring plate, and then the design parameters of the spring plate are adjusted to make , , thereby obtaining the design parameters of the spring plate, the design parameters including the width of the spring plate b ,thickness h And the distance between the ear support and the limit block a , the distance between the limit block and the hinged support l ; Step 3: Repeat the above steps 1 and 2 to obtain the design parameters of the spring plate used to simulate each connection point between the moving wing surface and the wing, and manufacture N sets of support components according to the design parameters. The N sets of support components are arranged in parallel along the span direction of the moving wing surface (13) and connected to the moving wing surface.

9. The design method according to claim 8, characterized in that: The true vertical stiffness and true horizontal stiffness The calculation method is: ， 。 10. The design method according to claim 9, characterized in that: The simulated vertical stiffness and simulated horizontal stiffness The calculation method is , ; In the formula, E is the elastic modulus of the spring plate, b is the width of the spring plate, h is the thickness of the spring plate, a is the distance between the ear support and the limit block, l It is the distance between the limit block and the hinged support.

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