A cable tension adjustment device for full-scale flutter wind tunnel tests

Abstract

The present invention discloses a cable tension adjustment device for full-scale flutter wind tunnel tests, which is used to provide tension adjustment for a cable support system controlled by a scimitar. It is characterized in that the device is installed on the scimitar and includes a connecting rod mechanism, a disc spring tensioning mechanism and a drive system connected in sequence. The disc spring tensioning mechanism and the drive system are both installed on a rotating frame, and the front end of the connecting rod mechanism is respectively connected to two main cables of the cable support system; the drive system provides pressure for the disc springs of the disc spring tensioning mechanism, and this pressure is transmitted to the main cables through the connecting rod mechanism to control the magnitude of the tension force of the main cables. The present invention solves the problem of the change in the support frequency caused by the change in the cable tension during the adjustment of the model pitching attitude in the wind tunnel test support scheme based on scimitar control.

Description

Technical Field

[0001] The present invention relates to a cable tension adjusting device for aircraft wind tunnel tests, specifically a cable tension adjusting device for full-scale flutter wind tunnel tests in which the cable tension received during model attitude adjustment remains basically unchanged. Background Art

[0002] With the development of aerospace technology, new configuration aircraft such as air-breathing hypersonic, variable configuration, cross-domain, and cross-medium aircraft have become research hotspots in academic and engineering research departments. The development of new aircraft configurations has made the interaction between components and subsystems increasingly complex. Aeroelastic divergence may occur in the wing-rudder-fuselage coupling mode. It is necessary to study the overall aircraft coupling flutter characteristics through full-scale wind tunnel tests.

[0003] To conduct full-scale flutter tests, a special support system needs to be designed for the model. On the one hand, it is necessary to have a low support frequency to simulate the free flight state of the aircraft. That is, after the model is suspended, the vibration frequencies of the model in five degrees of freedom, namely heave, pitch, roll, yaw, and sideslip, are low enough so that the dynamic characteristics of the aircraft model simulated in the wind tunnel are close enough to the dynamic characteristics during flight in the air. For the requirement of simulating the free flight state, the softer the support system, the better. On the other hand, during the wind tunnel test, it is necessary to use the support system to control and adjust the model to ensure that the aerodynamic and static loads received by the model are minimized, and to ensure the stability of the model attitude under the condition of changing oncoming flow dynamic pressure. For attitude control, the harder the support system, the better. It is not difficult to achieve only one of the above two functions. However, to meet the requirements of both functions, a cable tension adjustment mechanism for the support system needs to be designed to ensure the stability of the model attitude and maintain a low support frequency, without being affected by the tension change caused by the model attitude adjustment. Summary of the Invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and propose a cable tension adjusting device for full-scale flutter wind tunnel tests.

[0005] To achieve the above purpose, the present invention proposes a cable tension adjusting device for full-scale flutter wind tunnel tests, which is used to provide tension adjustment for a cable support system controlled by a scimitar. The device is installed on the scimitar and includes a link mechanism, a disc spring tensioning mechanism, and a drive system connected in sequence. Among them, both the disc spring tensioning mechanism and the drive system are installed on a rotating frame. The front end of the link mechanism is respectively connected to the two main cables of the cable support system; the drive system provides pressure for the disc springs of the disc spring tensioning mechanism, and this pressure is transmitted to the main cables through the link mechanism to control the magnitude of the tension force of the main cables.

[0006] As an improvement to the above device, the disc spring tensioning mechanism includes two branches with the same structure. Each branch includes a main connecting rod, a linear bearing, an adjustable disc spring stop, a disc spring, a disc spring pre-tightening nut, and a disc spring stop pull rod. Both ends of the connecting rod rear swing rod are respectively connected to a main connecting rod. A linear bearing, an adjustable disc spring stop, and a disc spring are sequentially sleeved on the main connecting rod, and the linear bearing is fixed on the rotating frame.

[0007] As an improvement to the above device, the adjustable disc spring stop is connected to the linear track slider through a disc spring stop pull rod. The axes of the main connecting rod, the linear bearing, the disc spring, the adjustable disc spring stop, and the linear track slider and their movement constraints are on the same straight line.

[0008] As an improvement to the above device, the drive system includes two branches with the same structure. Each branch includes a power source and a lever mechanism. Among them,

[0009] the power source includes a tension adjustment electric cylinder and a rotating frame angle adjustment electric cylinder;

[0010] the lever mechanism includes a tension adjustment electric cylinder push rod guide rail, a tension adjustment electric cylinder push rod, a tension adjustment electric cylinder lever, a linear track slider, and a lever fulcrum. The tension adjustment electric cylinder push rod can move within its guide rail. The end of the tension adjustment electric cylinder push rod is hinged to the power point of the tension adjustment electric cylinder lever. The resistance point of the tension adjustment electric cylinder lever can axially slide relative to the inner rotor inside the linear track slider. The inner rotor can rotate relative to the slider. The lever fulcrum is fixed on the rotating frame. The tension adjustment electric cylinder lever can axially slide relative to the inner rotor, and the rotor is hinged to the fulcrum.

[0011] As an improvement to the above device, the tension adjustment electric cylinder push rod is used to push the tension adjustment electric cylinder lever to swing around the lever fulcrum, driving the linear track slider to slide along the tension adjustment electric cylinder push rod guide rail, thereby driving the adjustable disc spring stop to move back and forth. The disc spring pre-tightening nut and the adjustable disc spring stop compress the disc spring, tighten the main connecting rod, and provide a pre-tightening force to the main cable.

[0012] As an improvement to the above device, the device is installed on the bending tool through a flange.

[0013] As an improvement to the above device, the force application point of the electric cylinder push rod pushed by the rotating frame angle adjustment electric cylinder is connected to the connection structure where the flange is located to form a triangular structure, enabling the rotating frame to rotate around the flange and having stability.

[0014] As an improvement to the above device, the rotation angle θ of the bending tool w and the rotation angle θ of the main cable satisfy the following formula:

[0015]

[0016] Among them, f is the distance from the front fixed point of the main cable to the rotation center of the curved knife, and r w is the rotation radius of the curved knife;

[0017] The compensation amount d of the main cable c satisfies the following formula:

[0018]

[0019] The displacement d of the push rod of the tension adjustment electric cylinder is:

[0020]

[0021] Among them, m1 is the horizontal distance from the lever fulcrum to the slider of the linear track, and m2 is the horizontal distance from the slider of the linear track to the push rod of the tension adjustment electric cylinder;

[0022] The included angle Δθ between the axis of the curved knife flange and the main cable and the stroke b of the rotation frame angle adjustment electric cylinder w satisfies the following formula:

[0023]

[0024] Among them, c is the distance from the point at the connection flange of the rotating frame and the curved knife to the point at the connection of the telescopic rod of the rotating frame angle adjustment electric cylinder and the curved knife, and a is the distance from the point at the connection flange of the rotating frame and the curved knife to the connection point of the base of the rotating frame angle adjustment electric cylinder and the rotating frame;

[0025] γ is the initial angle of the included angle between two line segments. One line segment is the connection line from the point at the connection flange of the rotating frame and the curved knife to the point at the connection of the telescopic rod of the rotating frame angle adjustment electric cylinder and the curved knife, and the other line segment is the connection line from the point at the connection flange of the rotating frame and the curved knife to the connection point of the telescopic rod of the rotating frame angle adjustment electric cylinder and the rotating frame, and satisfies the following formula:

[0026]

[0027] The included angle Δθ between the axis of the curved knife flange and the main cable is:

[0028]

[0029] As an improvement of the above device, the base of the tension adjustment electric cylinder is fixed on the rotating frame.

[0030] Compared with the prior art, the advantages of the present invention are as follows:

[0031] 1. For the suspension cable support system for curved knife control proposed by the present invention, its tension adjustment device is a brand-new adjustment device, which enables the tension of the main cable not to change due to the change in the cable length caused by the attitude adjustment of the aircraft model;

[0032] 2. The damping of the tension adjustment device of the present invention is outside the support system and does not affect the support frequency of the support system. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is the front view of the tension adjustment device;

[0034] Figure 2 is the top view of the tension adjustment device;

[0035] Figure 3(a) is the front view of the rotating frame;

[0036] Figure 3(b) is the isometric view of the rotating frame;

[0037] Figure 4 is the front view of the assembly of the tension adjustment electric cylinder, the rotating frame angle adjustment electric cylinder and the main cable tension adjustment lever;

[0038] Figure 5 is the isometric view of the 3D model of the disc spring stopper adjustment mechanism of the main cable tension adjustment device;

[0039] Figure 6 is the 3D model of the disc spring stopper adjustment mechanism of the main cable tension adjustment device, where Figure 6(a) is the front view, Figure 6(b) is the top view, and Figure 6(c) is the isometric view;

[0040] Figure 7 is the 3D model of the assembly of the disc spring tensioning mechanism of the main cable tension adjustment device;

[0041] Figure 8(a) is the 3D model of the scimitar control FSS subsystem, where Figure 8(a) is the front view and Figure 8(b) is the isometric view;

[0042] Figure 9 is the schematic diagram of the pitching attitude adjustment of the aircraft model;

[0043] Figure 10 is the relationship diagram between the scimitar angle and the pitching angle of the model;

[0044] Figure 11 is the relationship diagram between the scimitar curvature and the stroke (m) of the main cable tension adjustment electric cylinder;

[0045] Figure 12 is the relationship diagram between the scimitar angle and the length of the rotating frame angle adjustment electric cylinder;

[0046] Figure 13 is the influence of the change of the scimitar angle on the main cable tension under the condition of whether tension adjustment is applied.

[0047] REFERENCE MARKS

[0048] 1. Main connecting rod 2. Linear bearing

[0049] 3. Adjustable disc spring stopper 4. Disc spring

[0050] 5. Flange 6. Tension adjustment electric cylinder

[0051] 7. Tension adjustment electric cylinder push rod guide rail 8. Tension adjustment electric cylinder push rod

[0052] 9. Tension adjustment electric cylinder lever 10. Linear track and its slider

[0053] 11. Lever fulcrum 12. Rotary frame angle adjustment electric cylinder

[0054] 13. Disc spring preloading nut 14. Disc spring stop rod

[0055] 15. Main cable 16. Rotary frame

[0056] 17. Tension adjustment electric cylinder base 18. Tension adjustment device

[0057] 19. Front connection point of main cable 20. Aircraft model of model section

[0058] 21. Curved knife (the rotation center is at the centroid of the aircraft model) 22. Rear swing rod of connecting rod

[0059] 23. Front swing rod of connecting rod 24. Swing rod connecting rod

[0060] 25. Disc spring tensioning mechanism 26. Drive system

[0061] 27. Link mechanism Detailed implementation manners

[0062] The present invention relates to a cable tension adjustment device for aircraft wind tunnel tests. When adjusting the attitude of the model in the wind tunnel, the change in the cable length will increase or decrease the tension, and the change in the cable tension will cause a change in the system support frequency. Seriously, it will cause the model to become unstable, resulting in major losses and accidents. Therefore, the real-time adjustment of the cable tension during the model attitude adjustment can ensure the support frequency of the support system, so as to achieve the simulation of the free flight state of the aircraft. That is, after the model is suspended, the vibration frequencies of the model in five degrees of freedom, such as heave, pitch, roll, yaw and sideslip, are basically kept unchanged, so that the dynamic characteristics of the aircraft model simulated in the wind tunnel are close enough to the dynamic characteristics during flight in the air.

[0063] The present invention relates to a cable tension adjustment device for aircraft wind tunnel tests. To achieve the above object, the present invention provides the following technical solutions: The tension adjustment device is as Figure 1As shown in the figure, it consists of two main connecting rods 1, two sets of linear bearings 2, two adjustable disc spring stoppers 3, disc springs 4, flange plates 5, a tension adjustment electric cylinder 6, a tension adjustment electric cylinder push rod guide rail 7, a tension adjustment electric cylinder push rod 8, a tension adjustment electric cylinder lever 9, a linear track slider 10, a lever fulcrum 11, a rotary frame angle adjustment electric cylinder 12, a disc spring pre-tightening nut 13, a disc spring stopper pull rod 14, a steel cable 15, a rotary frame 16, a tension adjustment electric cylinder base 17, etc.

[0064] As Figure 2 shown in the figure, the main connecting rod 1 and its linear bearing 2 are installed in front of the rotary frame. The main connecting rod passes through the linear bearing, and the linear bearing is fixed on the rotary frame 16. The main connecting rod passes through the disc spring 4, and the disc spring can be compressed by the disc spring pre-tightening nut 13 and the adjustable disc spring stopper 3 to tighten the main connecting rod and provide a pre-tightening force. The adjustable disc spring stopper is connected to the linear track slider through the disc spring stopper pull rod 14. Therefore, the movement of the linear track slider can drive the movement of the adjustable disc spring stopper 3, so as to adjust the compression limiting position of the disc spring 4 and achieve the purpose of adjustable tension force.

[0065] The tension adjustment electric cylinder base 17 is fixed on the rotary frame 16. The tension adjustment electric cylinder push rod 7 provides thrust, and the push rod moves in the track fixed on the rotary frame to offset the radial force of the push rod, so that the electric cylinder is only subject to axial load. The linear track slider is pushed by the tension adjustment electric cylinder lever. The lever fulcrum 11 is fixed on the rotary frame, and the track where the linear guide rail slider is located is also fixedly connected to the rotary frame, so that the axes and movement ranges of the connecting rod, linear bearing, disc spring, adjustable disc spring stopper, and linear guide rail slider are on a straight line.

[0066] The technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

[0067] Embodiment

[0068] As Figure 1 shown in the figure, the embodiment of the present invention proposes a cable tension adjustment device for a full-scale flutter wind tunnel test, which is used to provide tension adjustment for the cable support system controlled by a scimitar. The device includes a connecting rod mechanism 27, a disc spring tensioning mechanism 25, and a drive system 26 connected in sequence. The disc spring tensioning mechanism and the drive system are installed on the rotary frame. The front end of the connecting rod mechanism 27 is respectively connected to the two main cables of the cable support system. The device is installed on the scimitar 21; the drive system provides pressure for the disc spring of the disc spring tensioning mechanism, and this pressure is transmitted to the main cable through the connecting rod mechanism 27 to control the magnitude of the tension force of the main cable. The connecting rod rear swing rod 22, the connecting rod front swing rod 23, and the swing rod connecting rod 24 are as Figure 2 shown in the figure.

[0069] As Figure 1 、 Figure 2As shown, this device includes four modules, namely an installation platform, a drive system 26, a disc spring tensioning mechanism, and a linkage mechanism. On the left is the linkage between the main link and the main cable. The main cable is hinged to the front swing rod of the linkage, the main link is connected to the rear swing rod of the linkage through a spherical bearing, and the front and rear swing rods are hinged at both ends of a linkage.

[0070] I. Installation platform:

[0071] A rotating frame 16 and a flange 5.

[0072] The rotating frame is specifically shown in Figures 3(a) and 3(b).

[0073] II. Drive system:

[0074] It includes a power source and a lever mechanism. The power source has a tension adjustment electric cylinder 6 and a rotating frame angle adjustment electric cylinder 12; the lever mechanism includes a tension adjustment electric cylinder push rod 8, a tension adjustment electric cylinder lever 9, a linear track and its slider 10, and a lever fulcrum 11. The rotating frame angle adjustment electric cylinder 12 pushes, and the force application point of the electric cylinder push rod is connected to the connection structure where the flange is located. Its triangular structure enables the rotating frame to rotate around the flange and has stability. The drive system drives the tension adjustment electric cylinder lever to swing around the lever fulcrum through the tension adjustment electric cylinder push rod, drives the linear track slider to slide along the guide rail, and the slider drives the disc spring stopper to move back and forth.

[0075] As Figure 4 shown, the front view of the tension adjustment electric cylinder (upper), the rotating frame angle adjustment electric cylinder (middle), and the main cable tension adjustment lever (right).

[0076] III. Disc spring tensioning mechanism:

[0077] As Figure 5 shown:

[0078] It includes a main link 1, a linear bearing 2, a disc spring 4, a disc spring pre-tightening nut 13, a disc spring stopper 3 and its pull rod 14.

[0079] The drive system 26 of the tension adjustment device and the disc spring tensioning mechanism are installed on the installation platform.

[0080] The pull rod of the disc spring stopper is hinged to the stopper. The hole in the center of the stopper and the linear bearing are fitted with the main link shaft. The pre-tightening nut is connected to the main link shaft by an anti-loosening thread. The connection method is as Figure 5 shown. As shown in Figure 6, the lever is driven to swing by the tension adjustment electric cylinder push rod. The lever drives the linear guide rail slider to move back and forth. The linear guide rail slider pulls the disc spring stopper to move back and forth. The disc spring stopper pushes the disc spring to provide pressure. This pressure is transmitted to the main cable through the main link to control the tension of the main cable. The main link can slide relatively within the linear bearing to tighten or loosen the steel cable.

[0081] As Figure 7 shown is the 3D assembly model of the disc spring tensioning mechanism of the main cable tension adjustment device.

[0082] As shown in FIGS. 8(a) and 8(b), the tension adjustment device 18 is installed on the bending blade 21 and is connected to the two main cables of the support system through the main connecting rod 1. The bending blade provides support for the tension adjustment device and controls the pitch attitude by swinging up and down. This device compensates for the change in the main cable tension during the adjustment of the model pitch attitude.

[0083] The tension adjustment device 18 is installed on the bending blade 21 through the flange 5, and the main connecting rod 1 of the tension adjustment device is connected to the two main cables 15 of the support system through the connecting rod 27. The bending blade 21 provides support for the tension adjustment device and controls the pitch attitude of the aircraft model 20 by swinging up and down. Since the rotation centers of the bending blade and the main cable are different, this device compensates for the change in the main cable tension during the adjustment of the model pitch attitude.

[0084] The disc spring 4 is installed on the main connecting rod 1, and the disc spring 4 is compressed by the disc spring pre-tightening nut 13 and the disc spring stop 3 to provide a tension force for the main connecting rod 1. The main connecting rod 1 passes through the linear bearing 2 and is connected to the connecting rod on the main cable.

[0085] The adjustable disc spring stop 3 is sleeved on the main connecting rod. Through the adjustable disc spring stop pull rod numbered 14, the linear guide rail sliders of the disc spring stops numbered 10 on both sides are connected. The linear guide rail slider can be pulled by the lever numbered 9. Therefore, the displacement of the linear guide rail slider can pull the disc spring stop 3 to adjust the limited position of the disc spring. And the axes of the connecting rod 1, the linear bearing 2, the disc spring 4, the adjustable disc spring stop 5, and the linear guide rail slider and their movement constraints are on the same straight line.

[0086] The electric cylinder 12 for adjusting the angle of the rotating frame adjusts the angle of the adjustable rotating frame relative to the flange 5. It adjusts the rotating frame 16 according to the angle of the cable to make the axial direction of the connecting rod close to the direction of the steel cable and reduce the system friction. The tension adjustment electric cylinder pushes the lever to drive the displacement of the linear guide rail slider.

[0087] The movement relationship between the rotation angle of the bending blade 21 and the tension adjustment electric cylinder 6 and the electric cylinder 12 for adjusting the angle of the rotating frame.

[0088] The following gives the derivation process of the tension adjustment method. Figure 9 The movement schematic diagrams of the rotation of the bending blade 21, the tension adjustment electric cylinder 6, and the electric cylinder 12 for adjusting the angle of the rotating frame are given.

[0089] When the wind tunnel is working, by adjusting the angle of the bending blade 21, the pitch angle of the model is adjusted. According to the geometric relationship, the rotation angle θ W of the bending blade and the rotation angle θ of the main cable satisfy the following relationship:

[0090]

[0091] Among them, f is the distance from the front fixed point A of the main cable to the rotation center B of the bending knife, and r w is the rotation radius of the bending knife.

[0092] Since the radius of the bending knife is smaller than the rotation radius of the main cable, when the bending knife moves, if the tension of the main cable is not adjusted, it will cause the change of the main cable tension. In order to maintain the constant tension of the main cable, it is necessary to adjust the displacement of the electric cylinder to compensate for the change of the main cable tension caused by different rotation radii and rotation centers. The main cable compensation amount d c satisfies

[0093]

[0094] The displacement d of the push rod of the electric push cylinder is

[0095]

[0096] Among them, m1 is the horizontal distance from the lever fulcrum G to the guide rail slider F, and m2 is the horizontal distance from the guide rail slider F to the push rod H of the tension adjusting electric cylinder, as Figure 9 shown.

[0097] Due to different bending knife radii and rotation centers, when the bending knife rotates, the rotating frame and the main cable are not in the same straight line. Therefore, the rotating frame angle adjusting electric cylinder maintains the rotating frame and the main cable in the same straight line. The bending knife angle and the push stroke b of the rotating frame angle adjusting electric cylinder w need to satisfy

[0098]

[0099] Among them, c is the distance from the point at the connection flange of the rotating frame and the bending knife to the point at the connection of the telescopic rod of the rotating frame angle adjusting electric cylinder and the bending knife, and a is the distance from the point C at the connection flange of the rotating frame and the bending knife to the connection point E of the base of the rotating frame angle adjusting electric cylinder and the rotating frame;

[0100] γ is the initial angle of the angle adjusting electric cylinder, the bending knife and the rotating frame, as Figure 9 shown ∠ECD, and satisfies

[0101]

[0102] Δθ is the included angle between the flange axis of the bending knife and the main cable, and satisfies

[0103]

[0104] In this embodiment, the distance f from the front fixed point A of the main cable to the rotation center B of the bending knife is f = 10m, and the rotation radius r of the bending knife w= 7m, the distance a from point C at the connection flange of the rotary frame and the machete to point E at the connection of the push rod of the electric cylinder for adjusting the rotary frame angle and the rotary frame is 2m, the original length b of the electric cylinder for adjusting the rotary frame angle is 1m, the distance c from point C at the connection flange of the rotary frame and the machete to point D at the connection of the push rod of the electric cylinder for adjusting the rotary frame angle and the machete is 2.5m, m1 = m2 = 0.5m.

[0105] It is necessary to achieve a model pitch angle adjustment range of -5° to +5°. According to Equation (1), the range that the machete needs to rotate is -13° to +13°, as Figure 10 shown.

[0106] In order to keep the main cable tension unchanged, adjust the displacement of the electric cylinder according to Equation (2) to compensate for the change in the main cable tension caused by different rotation radii and rotation centers. The displacement d of the adjusted electric cylinder satisfies as Figure 11 shown.

[0107] In order to keep the rotary frame and the main cable on the same straight line, according to Equation (4), the machete angle and the stroke b of the electric cylinder for adjusting the rotary frame angle w as Figure 12 shown.

[0108] Use a multi-body dynamics solver to solve the response of the aircraft model in the blowing state under the double-cable suspension system, calculate the model attitude adjustment process under wind tunnel blowing, and verify the effectiveness of feedback and feedforward control. Based on the established multi-body dynamics model of the machete control suspension system, through the multi-body dynamics solver, simulation analysis of the model attitude control under blowing is carried out in two cases: with feedback control and without feedback control. The time histories of the model pitch angle, the machete position angle, and the change in the main cable spring force are as Figure 13 shown. It can be seen from Figure 13 that because the rotation center of the machete is at the centroid of the aircraft model and the main cable connection point 19 is in front of the model, during the process of the machete controlling the pitch angle of the main cable, it is necessary to use a tension adjustment device to compensate for the change in the main cable length when the pitch angle changes, so that the change range of the main cable tension is small. Without tension adjustment, the change in the main cable tension is large.

[0109] Summary:

[0110] This design is different from the tension adjustment devices of other wind tunnel cable support systems at home and abroad. In order to solve the problem of cable tension changes caused by cable length changes during model attitude adjustment, the present invention adjusts the position of the disc spring stopper through a tension adjustment electric cylinder, thereby adjusting the cable tension of the support system, so that the tension received by the model remains unchanged. Then, the vibration frequencies of the model in five degrees of freedom, such as heave, pitch, roll, yaw, and sideslip, are basically kept unchanged, making the dynamic characteristics of the aircraft model simulated in the wind tunnel close enough to those during flight in the air. Moreover, components such as the lever, push rod, and linear track slider of this tension adjustment device are located behind the disc spring, and their damping is not included in the support system, reducing the influence of the mechanism on the support frequency and damping characteristics of the model.

[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the embodiments, those of ordinary skill in the art should understand that any modification or equivalent replacement of the technical solutions of the present invention does not depart from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A cable tension adjustment device for full-scale flutter wind tunnel tests, which is used to provide tension adjustment for a cable-supported system controlled by a scimitar, and is characterized in that, The device is installed on a curved knife and includes a connecting rod mechanism, a disc spring tensioning mechanism, and a drive system that are connected in sequence. The disc spring tensioning mechanism and the drive system are both installed on a rotating frame. The front end of the connecting rod mechanism is respectively connected to two main cables of a suspension cable support system; the drive system provides pressure for the disc springs of the disc spring tensioning mechanism, and this pressure is transmitted to the main cables through the connecting rod mechanism to control the magnitude of the tension force of the main cables. The disc spring tensioning mechanism includes two sets of branches with the same structure. Each set of branches includes a main connecting rod, a linear bearing, an adjustable disc spring stopper, a disc spring, a disc spring pre-tightening nut, and a disc spring stopper pull rod; both ends of the connecting rod swing rod of the connecting rod mechanism are respectively connected to a main connecting rod. A linear bearing, an adjustable disc spring stopper, and a disc spring are sequentially sleeved on the main connecting rod, and the linear bearing is fixed on the rotating frame. The adjustable disc spring stopper is connected to the slider of the linear track through a disc spring stopper pull rod. The axes of the main connecting rod, the linear bearing, the disc spring, the adjustable disc spring stopper, and the slider of the linear track and their movement constraints are on the same straight line. The drive system includes two sets of branches with the same structure. Each set of branches includes a power source and a lever mechanism, where the power source includes a tension adjustment electric cylinder and a rotating frame angle adjustment electric cylinder; The end of the push rod of the tension adjustment electric cylinder is hinged to the power point of the lever of the tension adjustment electric cylinder, and the lever fulcrum is fixed on the rotating frame; by pushing the push rod of the tension adjustment electric cylinder to swing the lever of the tension adjustment electric cylinder around the lever fulcrum, it drives the slider of the linear track to slide along the linear track, thereby driving the adjustable disc spring stopper to move back and forth. The disc spring pre-tightening nut presses the disc spring with the adjustable disc spring stopper, tightens the main connecting rod, and provides a pre-tightening force to the main cable. The rotating frame is installed on the curved knife through a flange; One end of the telescopic rod of the rotating frame angle adjustment electric cylinder is connected to the rotating frame, and the other end is connected to the curved knife, so that the rotating frame can rotate around the flange.

2. The cable tension adjusting device for full-scale flutter wind tunnel test according to claim 1, wherein The rotation angle θ of the machete w and the rotation angle θ of the main cable satisfy the following formula: where f is the distance from the front fixed point of the main cable to the rotation center of the curved blade, and r w is the rotation radius of the curved blade; Main cable compensation amount d c Satisfies the following formula: The displacement d of the push rod of the tension adjustment electric cylinder is: where m1 is the horizontal distance from the lever fulcrum to the slider of the linear track, and m2 is the horizontal distance from the slider of the linear track to the push rod of the tension adjustment electric cylinder; The included angle Δθ between the axis of the curved flange and the main cable and the stroke b of the electric cylinder for adjusting the angle of the rotating frame w Satisfy the following formula: where c is the distance from the point at the flange connection of the rotating frame and the curved knife to the point at the connection of the telescopic rod of the rotating frame angle adjustment electric cylinder and the curved knife, and a is the distance from the point at the flange connection of the rotating frame and the curved knife to the connection point of the base of the rotating frame angle adjustment electric cylinder and the rotating frame; γ is the initial angle of the included angle between two line segments. One line segment is the connection line from the point at the flange connection of the rotating frame and the curved knife to the point at the connection of the telescopic rod of the rotating frame angle adjustment electric cylinder and the curved knife, and the other line segment is the connection line from the point at the flange connection of the rotating frame and the curved knife to the connection point of the telescopic rod of the rotating frame angle adjustment electric cylinder and the rotating frame, satisfying the following formula: The included angle Δθ between the axis of the curved knife flange and the main cable is:

3. The cable tension adjusting device for full-scale flutter wind tunnel test according to claim 1, characterized in that The base of the tension adjustment electric cylinder is fixed on the rotating frame.

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