A wind tunnel fence structure based on particle dampers

Abstract

The present application belongs to the field of wind tunnel structure design, and discloses a wind tunnel adjusting sheet structure based on a particle damper, which comprises a test section, an adjusting sheet assembly, a connecting rod, a particle damper unit, a side wall plate and a dynamic seal. The wind tunnel adjusting sheet structure comprises a transonic second throat or a supersonic diffusion section composed of the adjusting sheet assembly symmetrically arranged upward and downward after the test section and the two side wall plates symmetrically arranged left and right. The adjusting sheet assembly comprises three adjusting sheets connected in sequence and the particle damper units fixed to the leeward surfaces of the adjusting sheets. The middle adjusting sheet is connected with an external driving mechanism through the connecting rod installed on the leeward surface. When the adjusting sheet vibrates, the damping particles in the particle damper unit are driven to collide and rub, so as to dissipate the fluid-structure coupling vibration energy. The wind tunnel adjusting sheet structure based on the particle damper has the advantages of excellent vibration reduction performance, strong environmental adaptability, small additional mass and flexible layout, and significantly improves the reliability and safety of the wind tunnel operation.

Description

Technical Field

[0001] This invention belongs to the field of wind tunnel structural design, specifically relating to a wind tunnel regulating plate structure based on a particle damper. Background Technology

[0002] Wind tunnels are indispensable key ground-based testing equipment for aerodynamic research. As aerospace vehicles develop towards higher speeds and more complex aerodynamic configurations, higher demands are placed on the testing capabilities of transonic and supersonic wind tunnels. In transonic and supersonic wind tunnels, a three-section control plate assembly is typically used as the core airflow control device. In transonic wind tunnels, this three-section control plate assembly is usually called the transonic second throat, and in supersonic wind tunnels, it is usually called the supersonic diffusion section. By interlocking the three sections of the control plate assembly to change the throat area, effective control of Mach number, shock wave position, and noise can be achieved.

[0003] A three-section regulating plate assembly typically consists of a front regulating plate, a middle regulating plate, and a rear regulating plate, hinged sequentially and symmetrically arranged downstream of the test section. During high-speed operation, the three-section regulating plate assembly is subjected to extreme aerodynamic loads caused by shock waves, turbulence, and complex pressure fluctuations. This multi-degree-of-freedom, lightweight, thin-walled flexible three-section regulating plate assembly is highly susceptible to strong fluid-structure interaction vibrations with the airflow, generating broadband random vibrations and potential flutter. Engineering practice shows that fluid-structure interaction vibrations can lead to the following serious consequences: overload alarms in the drive mechanism, interfering with the normal operation of the test process; accelerated structural fatigue damage, threatening equipment safety; and the generation of high-decibel aerodynamic noise, deteriorating the test environment and affecting measurement accuracy. To suppress fluid-structure interaction vibrations, traditional techniques mainly focus on enhancing the structural stiffness of the control plate assembly, such as increasing the size of the reinforcing ribs, using thicker plates, or adding a confinement layer damping. However, simply increasing the structural stiffness will significantly increase the structural weight, placing an additional burden on the drive system, and its effect on suppressing mid-to-high frequency vibrations is limited. Meanwhile, traditional viscoelastic confinement layer damping materials are sensitive to ambient temperature, and their performance will significantly degrade under aerodynamic heating or low-temperature conditions generated during wind tunnel operation, resulting in insufficient durability.

[0004] As a highly efficient passive vibration reduction method, particle damping technology dissipates vibration energy through inelastic collisions and friction between damping particles and between damping particles and the cavity wall within a sealed cavity composed of a cavity and end caps. It has significant advantages such as wide vibration reduction frequency band, insensitivity to environmental factors such as temperature and vacuum, simple structure, good durability, and small added mass.

[0005] Currently, there is an urgent need to develop a wind tunnel regulating plate structure based on particle dampers. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a wind tunnel regulating plate structure based on a particle damper to overcome the defects of the prior art.

[0007] The wind tunnel regulating plate structure based on a particle damper of the present invention includes a test section, regulating plate assembly, connecting rod, particle damper unit, side wall plate, and dynamic seal. The regulating plate assembly is located downstream of the test section and includes two symmetrically distributed sets of regulating plate assemblies. Each set of regulating plate assemblies includes a front regulating plate, a middle regulating plate, and a rear regulating plate that are sequentially hinged along the direction of supersonic airflow. The side wall plate and the regulating plate assembly form a transonic second throat or supersonic diffusion section with a rectangular cross section. A dynamic seal is provided at the intersection of the regulating plate assembly and the side wall plate. The middle regulating plate is connected to an external drive mechanism through a connecting rod installed on the leeward side. The particle damper unit is installed on the leeward side of the regulating plate assembly and is used to dissipate the fluid-structure interaction vibration energy caused by oblique shock waves and normal shock waves, thereby achieving broadband vibration reduction of the regulating plate assembly.

[0008] Furthermore, the leeward side of the front adjustment plate, the middle adjustment plate, and the rear adjustment plate is provided with orthogonal grid-like reinforcing ribs, which are rectangular metal plates.

[0009] Furthermore, the particle damper unit includes a cavity, damping particles, an end cap, and a connector; the end cap is fixedly connected to the cavity via the connector; the damping particles are filled in the sealed cavity formed by the cavity and the end cap.

[0010] Furthermore, the damping particles are one or a mixture of two or more of the following: metal particles, ceramic particles, and high-density polymer particles; the filling rate of the damping particles is 50% to 95% of the volume of the sealed cavity.

[0011] Furthermore, the number of particle damper units is several, and the particle damper units are arranged in a distributed manner based on the modal displacement peak region of the regulating plate assembly.

[0012] Furthermore, the particle damper unit includes a type I particle damper and a type II particle damper. The volume and weight of the type I particle damper are greater than those of the type II particle damper, respectively. The type I particle damper is located on the central symmetry line of the front, middle, and rear adjusting plates, and dissipates the vibration energy of the transverse bending deformation through fluid-structure interaction. The type II particle damper is located on the edges of the front, middle, and rear adjusting plates, and is symmetrically distributed on the left and right sides, and dissipates the vibration energy of the transverse torsional mode through fluid-structure interaction.

[0013] Furthermore, the particle damper unit and the regulating plate assembly are connected by adhesive bonding, bolting, or welding.

[0014] The wind tunnel regulating plate structure based on particle damper of the present invention solves the problems that traditional wind tunnel regulating plates are prone to strong vibration and noise in high-speed airflow, while existing vibration reduction methods such as weight increase or viscoelastic damping have limited effect, poor environmental adaptability or large added mass.

[0015] The wind tunnel regulating plate structure based on particle dampers of this invention has excellent broadband vibration reduction performance and operational safety: the particle damper dissipates energy through inelastic collisions and friction, effectively suppressing the broadband random vibration and flutter tendency generated by the regulating plate in complex airflows, fundamentally reducing the risk of overload of the drive mechanism, structural fatigue, and equipment jamming, and significantly improving the operational safety and reliability of wind tunnel tests; it has excellent environmental adaptability and durability: using inert materials including metals and ceramics as damping particles, the vibration reduction unit can maintain stable performance in the aerodynamic heating or low temperature environment that may occur during wind tunnel operation, without the worry of aging or failure, overcoming the disadvantage of the limited temperature range of traditional viscoelastic damping materials, and is suitable for the harsh working conditions of wind tunnels; it has flexible lightweight design and maintainability: the particle damper has a compact structure, small added mass, and can be installed by detachable methods such as bolt connection; combined with the optimized layout method based on mode shape, the arrangement position and number of dampers can be flexibly adjusted according to the specific vibration modes in the actual test, so as to achieve precise optimization of vibration reduction effect and convenient maintenance of structure.

[0016] The wind tunnel regulating plate structure based on particle dampers of the present invention has the advantages of excellent vibration reduction performance, strong environmental adaptability, small added mass and flexible layout, which can significantly improve the reliability and safety of wind tunnel operation and has practical engineering value. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the wind tunnel regulating plate structure based on the particle damper of the present invention; Figure 2 for Figure 1 AA cross-section view; Figure 3a The modal analysis diagram (first mode shape) of the regulating plate in the wind tunnel regulating plate structure based on particle damper of the present invention is shown. Figure 3b This is a modal analysis diagram (second-order vibration mode) of the regulating plate in the wind tunnel regulating plate structure based on particle damper of the present invention. Figure 3c The modal analysis diagram (third vibration mode) of the regulating plate in the wind tunnel regulating plate structure based on particle damper of the present invention is shown. Figure 3d This is a modal analysis diagram (fourth mode) of the regulating plate in the wind tunnel regulating plate structure based on particle damper of the present invention. Figure 4aThis is a schematic diagram (front view) of the regulating plate structure in the wind tunnel regulating plate structure based on the particle damper of the present invention. Figure 4b This is a side view of the regulating plate structure in the wind tunnel regulating plate structure based on the particle damper of the present invention. Figure 5 This is a comparison of the effective acceleration response curves of the regulating plate with and without particle dampers under the same random load.

[0018] Figure 1 , Figure 2 In the middle section, 1. Test section; 2. Adjustment plate assembly; 3. Connecting rod; 4. Particle damper unit; 5. Side wall plate; 6. Dynamic seal; 7. Type I particle damper; 8. Type II particle damper; 21. Front adjustment plate; 22. Middle adjustment plate; 23. Rear adjustment plate; 41. Cavity; 42. Damping particles; 43. End cap; 44. Connector.

[0019] Figures 3a-3d In the text, “U, Magnitude” represents modal displacement, with the unit being mm. Detailed Implementation

[0020] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0021] Example: Figure 1 , Figure 2 As shown, the wind tunnel regulating plate structure based on particle damper in this embodiment includes a test section 1, regulating plate assembly 2, connecting rod 3, particle damper unit 4, side wall plate 5, and dynamic seal 6. The regulating plate assembly 2 is located downstream of the test section 1 and includes two symmetrically distributed sets of regulating plate assemblies 2. Each set of regulating plate assemblies 2 includes a front regulating plate 21, a middle regulating plate 22, and a rear regulating plate 23 that are sequentially hinged along the direction of supersonic airflow. The side wall plate 5 and the regulating plate assembly 2 form a transonic second throat or supersonic diffusion section with a rectangular cross section. A dynamic seal 6 is provided at the intersection of the regulating plate assembly 2 and the side wall plate 5. The middle regulating plate 22 is connected to an external drive mechanism through the connecting rod 3 installed on the leeward side. The particle damper unit 4 is installed on the leeward side of the regulating plate assembly 2 and is used to dissipate the fluid-structure interaction vibration energy caused by oblique shock waves and normal shock waves, thereby achieving broadband vibration reduction of the regulating plate assembly 2.

[0022] Furthermore, the leeward surfaces of the front adjustment plate 21, the middle adjustment plate 22, and the rear adjustment plate 23 are provided with orthogonal grid-like reinforcing ribs, which are rectangular metal plates.

[0023] Furthermore, the particle damper unit 4 includes a cavity 41, damping particles 42, an end cap 43, and a connector 44; the end cap 43 is fixedly connected to the cavity 41 through the connector 44; the damping particles 42 are filled in the sealed cavity formed by the cavity 41 and the end cap 43.

[0024] Furthermore, the damping particles 42 are one or a mixture of two or more of the following: metal particles, ceramic particles, and high-density polymer particles; the filling rate of the damping particles 42 is 50% to 95% of the volume of the sealed cavity.

[0025] Furthermore, the number of particle damper units 4 is several, and the particle damper units 4 are disposed in the modal displacement peak region of the adjusting plate assembly 2 and based on, for example... Figure 3a , Figure 3b , Figure 3c , Figure 3d The modal vibration modes of the adjustment plate assembly 2 shown are distributed.

[0026] Furthermore, the particle damper unit 4 includes, as follows: Figure 4a , Figure 4b The Type I particle damper 7 and Type II particle damper 8 shown are shown. The volume and weight of the Type I particle damper 7 are greater than those of the Type II particle damper 8. The Type I particle damper 7 is located on the central symmetry line of the front adjustment plate 21, the middle adjustment plate 22 and the rear adjustment plate 23, and dissipates the vibration energy of the transverse bending deformation through fluid-structure interaction. The Type II particle damper 8 is located on the edge of the front adjustment plate 21, the middle adjustment plate 22 and the rear adjustment plate 23, and is symmetrically distributed on the left and right sides, and dissipates the vibration energy of the transverse torsional mode through fluid-structure interaction.

[0027] Furthermore, the particle damper unit 4 and the adjusting plate assembly 2 are connected by adhesive bonding, bolting, or welding.

[0028] In this embodiment, an acceleration sensor is arranged on the base plate of the middle regulating plate 22, and a random vibration test is conducted using a vibrator. The acceleration sensor records the time-domain curve of the acceleration response of the middle regulating plate 22. Based on the time-domain data, the effective acceleration value of the most recent second data segment is calculated every second to obtain the following result: Figure 5 The graph shows a comparison of the effective acceleration response curves of the regulating plate 22 with and without particle dampers under the same random load. Figure 5 It can be seen that the acceleration response curve of the regulating plate 22 with particle damper is significantly smaller than that of the regulating plate 22 without particle damper.

[0029] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. For those skilled in the art, all features disclosed in the present invention, or all steps in all methods or processes disclosed, except for mutually exclusive features and / or steps, can be combined in any way without departing from the principles of the present invention. The present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A wind tunnel regulating plate structure based on a particle damper, characterized in that, The test section (1), the regulating plate assembly (2), the connecting rod (3), the particle damper unit (4), the side wall plate (5), and the dynamic seal (6) are included. The regulating plate assembly (2) is located downstream of the test section (1) and includes two sets of regulating plate assemblies (2) symmetrically distributed. Each set of regulating plate assemblies (2) includes a front regulating plate (21), a middle regulating plate (22), and a rear regulating plate (23) that are hinged sequentially along the direction of supersonic airflow. The side wall plate (5) and the regulating plate assembly (2) form a transonic second throat or supersonic diffusion section with a rectangular cross section. A dynamic seal (6) is provided at the intersection of the regulating plate assembly (2) and the side wall plate (5). The middle regulating plate (22) is connected to the external drive mechanism through the connecting rod (3) installed on the leeward side. The particle damper unit (4) is installed on the leeward side of the regulating plate assembly (2) to dissipate the fluid-structure coupling vibration energy caused by oblique shock waves and normal shock waves, thereby realizing broadband vibration reduction of the regulating plate assembly (2).

2. The wind tunnel regulating plate structure based on a particle damper according to claim 1, characterized in that, The front adjustment plate (21), the middle adjustment plate (22) and the rear adjustment plate (23) are provided with orthogonal grid-shaped reinforcing ribs on their leeward sides. The grid-shaped reinforcing ribs are rectangular metal plates.

3. The wind tunnel regulating plate structure based on a particle damper according to claim 1, characterized in that, The particle damper unit (4) includes a cavity (41), damping particles (42), an end cap (43), and a connector (44); the end cap (43) is fixedly connected to the cavity (41) through the connector (44); the damping particles (42) are filled in the sealed cavity formed by the cavity (41) and the end cap (43).

4. The wind tunnel regulating plate structure based on a particle damper according to claim 3, characterized in that, The damping particles (42) are one or a mixture of two or more of the following: metal particles, ceramic particles, and high-density polymer particles; the filling rate of the damping particles (42) is 50% to 95% of the volume of the sealed chamber.

5. The wind tunnel regulating plate structure based on a particle damper according to claim 1, characterized in that, The number of particle damper units (4) is several. The particle damper units (4) are set in the modal displacement peak region of the regulating plate assembly (2) and are distributed based on the modal vibration mode of the regulating plate assembly (2).

6. The wind tunnel regulating plate structure based on a particle damper according to claim 1, characterized in that, The particle damper unit (4) includes a type I particle damper (7) and a type II particle damper (8). The volume and weight of the type I particle damper (7) are greater than those of the type II particle damper (8). The type I particle damper (7) is located on the central symmetry line of the front adjustment plate (21), the middle adjustment plate (22) and the rear adjustment plate (23), and dissipates the fluid-structure coupling vibration energy for transverse bending deformation. The type II particle damper (8) is located on the edge of the front adjustment plate (21), the middle adjustment plate (22) and the rear adjustment plate (23), and is symmetrically distributed on the left and right sides, and dissipates the fluid-structure coupling vibration energy for transverse torsional vibration mode.

7. The wind tunnel regulating plate structure based on a particle damper according to claim 1, characterized in that, The particle damper unit (4) and the regulating plate assembly (2) are connected by adhesive bonding, bolting or welding.

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