Two-degree-of-freedom model flutter supporting device

Abstract

The invention discloses a two-degree-of-freedom model flutter supporting device, and relates to the field of wind tunnel model flutter supporting devices. The two-degree-of-freedom model flutter supporting device comprises a sliding rail and a supporting unit. According to the two-degree-of-freedom model flutter supporting device provided by the embodiment of the invention, the supporting frame of the supporting unit is movably arranged on the sliding rail, so that the supporting frame can move up and down on the sliding rail, the sinking and floating movement of the connecting frame is simulated, the supporting frame and the connecting frame are connected through the bearing, and the connecting frame can rotate around the bearing; according to the embodiment of the invention, through the cooperation of the sliding rail and the rotating shaft, the movement in other directions except sinking, floating and pitching can be restrained, and meanwhile, the sliding rail and the bearing are used as carriers to bear larger external force. The problems that a double-cable suspension supporting system in the prior art is difficult to restrain the degree of freedom in other directions and is not suitable for a large and heavy model test are solved.

Description

Technical Field

[0001] The invention relates to the field of wind tunnel model flutter support devices, in particular to a two-degree-of-freedom model flutter support device. Background Art

[0002] The flutter response study of large and strong flexible aircraft mechanisms must find out the influence of rigid body modes, otherwise the elastic modal response control cannot be completed completely independently. The wind tunnel model flutter test requires the heave and pitch degrees of freedom, so that the model can move freely in the heave and pitch directions under the test conditions.

[0003] The existing flutter response support method is a double-cable support system, which allows the model to move in all rigid body degrees of freedom. However, the model flutter response support system only needs to have movement freedom in the heave and pitch directions. The existing double-cable suspension support system is difficult to constrain the degrees of freedom in other directions and is not suitable for large and heavy model tests.

[0004] Therefore, providing a two-degree-of-freedom model flutter support device with strong bearing capacity is a technical problem that needs to be solved urgently by technical personnel in this field. Summary of the invention

[0005] The invention discloses a two-degree-of-freedom model flutter support device to at least partially improve the above technical problems.

[0006] In order to solve the above problems, the present invention adopts the following technical solutions: The embodiment of the present application provides a two-degree-of-freedom model flutter support device, comprising: a slide rail and a support unit. The support unit comprises: a support frame, a connection frame and a bearing, the support frame can move along the slide rail under the action of aerodynamic load to simulate the sinking and floating movement of the connection frame; the connection frame is used to connect an external model; the bearing is connected to the support frame and the connection frame, so that the connection frame can rotate around the bearing to simulate the pitching movement of the connection frame.

[0007] In one embodiment, the support unit further includes: a plurality of rollers, the plurality of rollers are disposed on the support frame and are evenly distributed on opposite sides of the slide rail, and the rollers can roll freely on the slide rail.

[0008] In one embodiment, the support unit further includes: a slide drive assembly, the slide drive assembly is connected to the connection frame and to the support frame, and the slide drive assembly is used to limit the pitch angle of the connection frame.

[0009] In one embodiment, the slide drive assembly includes: a first slide, a second slide and a baffle, the first slide and the second slide are connected to the support frame, the baffle is connected to the connecting frame, and the connecting frame is located between the first slide and the second slide. When the connecting frame rotates around the bearing, the baffle is used to abut against the first slide or the second slide to limit the pitch direction freedom of the connecting frame.

[0010] In one embodiment, the slide drive assembly also includes: a forward and reverse screw rod and a driver, one end of the forward and reverse screw rod is connected to the driver, and the other end is connected to the support frame, the driver is connected to the support frame, the first slide and the second slide are connected to the forward and reverse screw rod, and the driver is used to drive the first slide and the second slide to move on the forward and reverse screw rod to change the maximum pitch angle of the connection frame.

[0011] In one embodiment, the two-degree-of-freedom model flutter support device further includes: a shock absorbing unit, which is arranged at both ends of the slide rail and is used to absorb shock to the support unit.

[0012] In one embodiment, the shock absorbing unit includes: a support and an elastic member, the support is fixed to an end of the slide rail, the elastic member is arranged on the support, and the elastic deformation direction of the elastic member is the same as the extension direction of the slide rail.

[0013] In one embodiment, the two-degree-of-freedom model vibration support device further includes: a brake unit, which is connected to the support unit and is used to prevent the connection frame from sinking and floating.

[0014] In one embodiment, the brake unit includes: a brake pad and a hydraulic cylinder, the brake pad is arranged on the support frame, the hydraulic cylinder is arranged on the support frame and connected to the brake pad, and is used to drive the brake pad to abut against the slide rail to generate a friction force opposite to the movement direction of the connecting frame.

[0015] In one embodiment, the brake pad is arranged on a surface of the support frame facing the slide rail, and the hydraulic cylinder is arranged on a surface of the support frame facing away from the slide rail.

[0016] The technical solution adopted by the present invention can achieve the following beneficial effects: The two-degree-of-freedom model flutter support device provided in the embodiment of the present application, through the support frame of the support unit movably set on the slide rail, so that the support frame can move up and down on the slide rail, thereby simulating the sinking and floating movement of the connecting frame, and the support frame and the connecting frame are connected by a bearing, so that the connecting frame can rotate around the bearing, thereby simulating the pitching movement of the connecting frame. In this embodiment, the connection frame used for connecting the external model in the support unit can only perform sinking and floating movement and pitching movement through the cooperation of the slide rail and the rotating shaft, so that the movement in other directions except sinking and pitching can be constrained. At the same time, the use of the slide rail and the bearing as a carrier can withstand greater external force, which solves the problem that the double-cable suspension support system in the prior art is difficult to constrain the degrees of freedom in other directions and is not suitable for large and heavy model tests. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic structural diagram of a two-degree-of-freedom model flutter support device in one embodiment of the present application is shown; Figure 2 A schematic structural diagram of a support unit and a brake unit in a two-degree-of-freedom model flutter support device in one embodiment of the present application is shown; Figure 3 A structural schematic diagram showing a partial structure of a support unit and a brake unit in a two-degree-of-freedom model flutter support device in an embodiment of the present application from another perspective; Figure 4 for Figure 1 Enlarged view of point A in the middle.

[0019] In the figure: 1. two-degree-of-freedom model flutter support device; 10. slide rail; 110. groove; 20. support unit; 210. support frame; 220. connecting frame; 230. bearing; 240. roller; 250. slide drive assembly; 251. first slide; 252. second slide; 253. baffle; 254. forward and reverse screw rod; 255. driver; 30. shock absorbing unit; 310. support; 320. elastic member; 40. brake unit; 410. brake pad; 420. hydraulic cylinder. DETAILED DESCRIPTION

[0020] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0021] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0022] The inventive concept of the present application is described here: The study of the flutter response of large and flexible aircraft mechanisms must identify the influence of rigid body modes. The wind tunnel model flutter test requires heave and pitch degrees of freedom, so that the model can move freely in the heave and pitch directions under test conditions.

[0023] The existing flutter response support method is a double-cable support system, which allows the model to move in all rigid body degrees of freedom. However, in the model flutter response support system, it is only necessary to satisfy the freedom of movement in the sinking and pitching directions. The existing double-cable suspension support system is difficult to constrain the degrees of freedom in other directions. This will not only increase the difficulty of the experiment, but also lead to low accuracy of the experimental data. It is necessary to repeat the experiment many times to reduce or eliminate the impact of the above problems. In addition, since the double-cable suspension support system uses ropes to support the model, when there is a gust load, the double-cable suspension support system has poor stability and is prone to flutter divergence. Therefore, the double-cable suspension support system is not suitable for large and heavy model tests.

[0024] Based on this, the inventor provides a two-degree-of-freedom model flutter support device, in which the two-degree-of-freedom model flutter support device utilizes the cooperation of slide rails and bearings so that the entire device can constrain other degrees of freedom except the sinking and floating directions and the pitching directions, and both the slide rails and the bearings can withstand strong loads to ensure that the experiment can proceed smoothly.

[0025] The following is combined with Figure 1-Figure 4 , the two-degree-of-freedom model flutter support device 1 provided in the present application is described in detail through specific embodiments and application scenarios.

[0026] See also Figure 1 The two-degree-of-freedom model flutter support device 1 provided in the embodiment of the present application may include: a slide rail 10 and a support unit 20 .

[0027] The support unit 20 can be movably arranged on the slide rail 10. Specifically, in this embodiment, the slide rail 10 can be arranged vertically, that is, the support unit 20 can move up and down on the slide rail 10. When the support unit 20 is connected to an external model, the sinking and floating movement of the model can be simulated.

[0028] Please also see Figure 1 and Figure 2 , the support unit 20 may include: a support frame 210, a connection frame 220 and a bearing 230. The embodiment of the present application does not limit the specific form and structure of the support frame 210 and the connection frame 220. For example, in one embodiment, the support frame 210 may be set as a frame structure, and the two ends of the support frame 210 are hollow, so that the support frame 210 can be sleeved on the slide rail 10 and can move along the slide rail under the action of the pneumatic load. The connection frame 220 can be connected to one end of the support frame 210, and the connection frame 220 can be used to connect an external model. In order to make the connection frame 220 rotate more evenly relative to the support frame 210, the bearing 230 can be set at the center of the connection frame 220, and is set at the center of the support frame 210, so that the connection frame 220 can be connected to the support frame 210 in a seesaw-like manner through the bearing 230. When the connection frame 220 is not subjected to external force, the heights of the two ends of the connection frame 220 are on the same horizontal plane.

[0029] Furthermore, the support frame 210 can be movably set on the slide rail 10. The embodiment of the present application does not limit the movable connection method between the support frame 210 and the slide rail 10. For example, in one embodiment, a roller 240 can be set on one of the support frame 210 and the slide rail 10, and the support frame 210 and the slide rail 10 can be movably connected through the roller 240.

[0030] In a specific embodiment, the support unit 20 may include a plurality of rollers 240, and the plurality of rollers may be disposed on the support frame 210 and evenly distributed on opposite sides of the slide rail 10, and the rollers 240 may be rollingly connected to the slide rail 10 and may roll freely on the slide rail 10. It should be noted that the embodiment of the present application does not limit the specific arrangement of the rollers 240, for example, in one embodiment, the rollers 240 may be arranged to be connected to two surfaces of the slide rail 10, and for example, in another embodiment, the rollers 240 may also be arranged to be connected to four surfaces of the slide rail 10, and the specific arrangement may be made according to actual conditions.

[0031] In addition, the embodiments of the present application do not limit the specific shape and size of the pulley. For example, as shown in the figure, the pulleys located on adjacent surfaces of the support frame 210 can be set to structures of different sizes and different quantities. This can facilitate the user to distinguish the installation orientation when installing the support frame 210 on the slide rail 10.

[0032] Furthermore, in one embodiment, the surface of the slide rail 10 may have a groove 110, and the roller 240 may be embedded in the aforementioned groove 110, so that the connection between the support frame 210 and the slide rail 10 can be more tightly connected, and the aforementioned groove 110 can also play a limiting role and installation guide role for the roller 240. It should be noted that the embodiment of the present application does not limit the specific structure of the groove 110, and the structure of the roller 240 can be specifically set accordingly.

[0033] Please also see Figure 2 and Figure 3 It is understandable that, in the process of simulating pitch motion, there is usually a certain limit on the maximum pitch angle, for example, the maximum pitch angle is usually limited to within ±5°. Therefore, in this embodiment, the support unit 20 may further include a slide drive assembly 250, which may be connected to the connection frame 220 and the support frame 210, and the slide drive assembly 250 may be used to limit the pitch direction freedom of the connection frame 220.

[0034] In a specific embodiment, the slide drive assembly 250 may include: a first slide 251, a second slide 252 and a baffle 253. The first slide 251 and the second slide 252 can be connected to the support frame 210, the baffle 253 can be connected to the connecting plate, and the baffle 253 can be located between the first slide 251 and the second slide 252. When the connecting frame 220 rotates around the bearing 230, the baffle 253 can be used to abut against the first slide 251 or the second slide 252 to limit the pitch direction freedom of the connecting frame 220.

[0035] It should be noted that the embodiments of the present application do not limit the specific structures of the first slide 251, the second slide 252 and the baffle 253. For example, in the present embodiment, the first slide 251, the second slide 252 and the baffle 253 can all be set to sheet structures. In some other embodiments, the first slide 251, the second slide 252 and the baffle 253 can also be set to other forms of structures, such as blocks, strips, etc., which can be set according to actual conditions.

[0036] As mentioned above, during the experiment, some special situations need to be simulated, for example, the model should be able to withstand a sudden deep pitch, that is, in this case, the maximum pitch angle is ±10°. To facilitate the adjustment of the maximum pitch angle, in one embodiment, the slide drive assembly 250 may also include: a forward and reverse screw rod 254 and a driver 255, one end of the forward and reverse screw rod 254 may be connected to the driver 255, and the other end may be connected to the support frame 210, the driver 255 may be connected to the support frame 210, the first slide 251 and the second slide 252 may be connected to the forward and reverse screw rod 254, and the driver 255 may be used to drive the first slide 251 and the second slide 252 to move on the forward and reverse screw rod 254, thereby changing the distance between the first slide 251 and the baffle 253 and changing the distance between the second slide 252 and the baffle 253, so as to achieve the effect of changing the maximum pitch angle of the limiting connection frame 220.

[0037] Also, see Figure 1 and Figure 4 In the process of simulating the sinking and floating motion, the model needs to be able to withstand the additional vertical speed caused by strong gusts or unstable design conditions (such as rear center of gravity conditions). In this case, a shock absorbing unit 30 must be provided in the direction of the model's sinking and floating freedom. The shock absorbing unit 30 can be used to reduce the impact on the model and prevent the model from being damaged and flying out of the slide rail 10.

[0038] In this embodiment, the shock absorbing unit 30 can be arranged at both ends of the slide rail 10 to reduce the shock of the support unit 20. The embodiment of the present application does not limit the specific form of the shock absorbing unit 30. For example, in one embodiment, the shock absorbing unit 30 may include a support 310 and an elastic member 320. The support 310 can be fixed to the end of the slide rail 10, and the elastic member 320 can be arranged on the support 310. The elastic deformation direction of the elastic member 320 can be the same as the extension direction of the slide rail 10. Before conducting the experiment, the support unit 20 can be arranged in the middle of the slide rail 10, so that the support unit 20 has sufficient moving space regardless of the direction of the sinking and floating movement.

[0039] As mentioned above, in one embodiment, the elastic member 320 can be embedded in the groove 110, which can help reduce the extra space occupied by the entire shock absorbing unit 30, thereby making the structure of the entire two-degree-of-freedom model flutter support device 1 more compact. At the same time, embedding the elastic member 320 in the groove 110 can also allow the groove 110 to position the elastic member 320, thereby preventing the elastic member 320 from flying out after being impacted by the support unit 20, resulting in the problem of shock absorption failure. It should be noted that the embodiment of the present application does not limit the specific form of the elastic member 320. For example, in some embodiments, the elastic member 320 can be a spring, a shrapnel or an airbag, etc., which can be specifically set according to actual conditions and is not limited here. In a more specific embodiment, the elastic member 320 can be a spring and is made of a strong 65Mn material.

[0040] Please refer again Figure 2 and Figure 3 In some embodiments, the two-degree-of-freedom model vibration support device 1 may further include a brake unit 40. When the model exhibits uncontrollable sinking and floating motions, the brake unit 40 may be used to stop the model to prevent unwanted vertical motion.

[0041] In this embodiment, the brake unit 40 can be connected to the support unit 20. Specifically, the brake unit 40 may include a brake pad 410 and a hydraulic cylinder 420. The brake pad 410 can be set on the support frame 210, and the hydraulic cylinder 420 can also be set on the support frame 210. The hydraulic cylinder 420 is connected to the brake pad 410 and is used to drive the brake pad 410 to abut against the slide rail 10 to generate a friction force in the opposite direction of the movement of the connecting frame 220, thereby braking the connecting frame 220.

[0042] The embodiment of the present application does not limit the number and position of the brake pads 410. For example, in one embodiment, two brake pads 410 may be provided, and the two brake pads 410 may be provided on opposite surfaces of the support frame 210. For example, in another embodiment, four brake pads 410 may be provided, and the four brake pads 410 may be evenly provided on each support frame 210. The specific arrangement may be based on actual conditions.

[0043] It should be noted that the embodiments of the present application do not limit the specific manner in which the brake pads 410 and the hydraulic cylinders 420 are arranged on the support frame 210. For example, in one embodiment, a bracket can be used to respectively arrange the brake pads 410 and the hydraulic cylinders 420 on the support frame 210. For example, in another embodiment, the brake pads 410 and the hydraulic cylinders 420 can also be respectively formed integrally with the support frame 210. The specific restrictions can be made according to actual conditions.

[0044] In a more specific embodiment, the brake pad 410 can be arranged on the surface of the support frame 210 facing the slide rail 10, and the hydraulic cylinder 420 can be arranged on the surface of the support frame 210 away from the slide rail 10. This can also make the structure of the entire two-degree-of-freedom model vibration support device 1 more compact.

[0045] In summary, the two-degree-of-freedom model flutter support device 1 provided in the embodiment of the present application, by movably setting the support frame 210 of the support unit 20 on the slide rail 10, so that the support frame 210 can move up and down on the slide rail 10, thereby simulating the floating and sinking movement of the connecting frame 220, and connecting the support frame 210 and the connecting frame 220 through the bearing 230, so that the connecting frame 220 can rotate around the bearing 230, thereby simulating the pitching movement of the connecting frame 220. In this embodiment, the cooperation of the slide rail 10 and the rotating shaft can make the connecting frame 220 used for connecting the external model in the support unit 20 only able to perform floating and sinking movements and pitching movements, thereby constraining movements in other directions except for floating and pitching. At the same time, using the slide rail 10 and the bearing 230 as a carrier can withstand greater external forces, thereby solving the problem that the two-cable suspension support system in the prior art is difficult to constrain the degrees of freedom in other directions and is not suitable for large and heavy model tests.

[0046] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0047] In addition, it should be noted that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in a reverse order according to the functions involved. For example, the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

[0048] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A two-degree-of-freedom model flutter support device, characterized in that: include: A slide rail and a support unit, wherein the support unit comprises: a support frame, a connection frame and a bearing, and the support frame can move along the slide rail under the action of a pneumatic load to simulate the sinking and floating movement of the connection frame; The connecting frame is used to connect to an external model; the bearing is connected to the supporting frame and the connecting frame, so that the connecting frame can rotate around the bearing to simulate the pitch motion of the connecting frame.

2. The two-degree-of-freedom model flutter support device according to claim 1, characterized in that: The support unit further comprises: a plurality of rollers, which are arranged on the support frame and evenly distributed on two opposite sides of the slide rail, and the rollers can roll freely on the slide rail.

3. The two-degree-of-freedom model flutter support device according to claim 1, characterized in that: The support unit further includes: a slide drive assembly, the slide drive assembly is connected to the connection frame and to the support frame, and the slide drive assembly is used to limit the pitch direction freedom of the connection frame.

4. The two-degree-of-freedom model flutter support device according to claim 3, characterized in that: The slide drive assembly includes: a first slide, a second slide and a baffle, the first slide and the second slide are connected to the support frame, the baffle is connected to the connecting frame, and the connecting frame is located between the first slide and the second slide. When the connecting frame rotates around the bearing, the baffle is used to abut against the first slide or the second slide to limit the pitch direction freedom of the connecting frame.

5. The two-degree-of-freedom model flutter support device according to claim 4, characterized in that: The slide drive assembly also includes: a forward and reverse screw rod and a driver, one end of the forward and reverse screw rod is connected to the driver, and the other end is connected to the support frame, the driver is connected to the support frame, the first slide and the second slide are connected to the forward and reverse screw rod, and the driver is used to drive the first slide and the second slide to move on the forward and reverse screw rod to change the maximum pitch angle of the connection frame.

6. The two-degree-of-freedom model flutter support device according to any one of claims 1 to 5, characterized in that: The two-degree-of-freedom model flutter support device further includes: a shock absorbing unit, which is arranged at both ends of the slide rail and is used to absorb shock to the support unit.

7. The two-degree-of-freedom model flutter support device according to claim 6, characterized in that: The shock absorbing unit comprises: a support and an elastic member, wherein the support is fixed to the end of the slide rail, the elastic member is arranged on the support, and the elastic deformation direction of the elastic member is the same as the extension direction of the slide rail.

8. The two-degree-of-freedom model flutter support device according to any one of claims 1 to 5, characterized in that: The two-degree-of-freedom model vibration support device also includes: a brake unit, which is connected to the support unit and is used to prevent the connection frame from sinking and floating.

9. The two-degree-of-freedom model flutter support device according to claim 8, characterized in that: The brake unit includes: a brake pad and a hydraulic cylinder. The brake pad is arranged on the support frame. The hydraulic cylinder is arranged on the support frame and connected to the brake pad for driving the brake pad to abut against the slide rail to generate a friction force opposite to the movement direction of the connection frame.

10. The two-degree-of-freedom model flutter support device according to claim 9, characterized in that: The brake pad is arranged on a surface of the support frame facing the slide rail, and the hydraulic cylinder is arranged on a surface of the support frame facing away from the slide rail.

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