Passive nonlinear energy-dissipating control structure and method for flutter suppression of aircraft panels

Abstract

The present invention belongs to the technical field of passive vibration reduction, and relates to a passive nonlinear energy-consuming control structure and method for flutter suppression of aircraft wall panels, comprising: a linear stiffness spring, a moving contact, and a static contact; one end of the linear stiffness spring is connected to the inner wall of the aircraft wall panel, and the other end is connected to the moving contact, the moving contact is slidably connected to the static contact, and the static contact is fixedly connected to the aircraft frame; Coulomb friction exists between the moving contact and the static contact; an angle is provided between the connecting line of the two ends of the linear stiffness spring and the vertical line of the wall panel; the present invention combines the linear stiffness spring with a Coulomb friction slider, so that when the aircraft wall panel flutters, the linear stiffness spring transfers the wall panel flutter nonlinearly to the Coulomb friction slider for energy consumption, and the slider plays a role in damping and suppressing the wall panel flutter; the present invention adopts reliable and commonly used springs and Coulomb friction sliders to achieve flutter suppression, so the present invention has a simple structure, low implementation difficulty, high reliability, and low implementation cost.

Description

Technical Field

[0001] The present invention belongs to the technical field of passive vibration reduction, and in particular relates to a passive nonlinear energy-dissipating control structure and method for suppressing flutter of aircraft wall panels. Background Art

[0002] Technological advances have enabled aircraft to achieve ever-increasing speeds, reaching supersonic or hypersonic speeds. As the vehicle's propulsion components, the skin's typical structural characteristics are light weight, high strength, and ultra-thin thickness. Many skins are approximately 0.5 mm thick and are typically fabricated as rectangular flat plates or thin sheets with a certain curvature. During flight, due to their ultra-thin thickness and exposure to supersonic airflow, the coupling of inertial forces, elastic forces, and the aerodynamic forces of the airflow flowing over the skin's panel surface produces a self-excited vibration, commonly known as flutter. The harmful effects of panel flutter include intense aerodynamic noise and fatigue damage. To reduce or suppress panel flutter, various vibration reduction methods have been employed in the prior art, such as the use of composite materials with damping and vibration reduction properties, carbon fiber composites, or metamaterials, as well as other laminated materials that increase viscous damping. Passive control methods for panel flutter suppression include installing acoustic black hole devices, nonlinear energy sinks, and adding panel constrained damping layers. Active control methods, however, often involve bonding piezoelectric materials to the panel surface.

[0003] However, current chatter suppression technology has the following shortcomings:

[0004] 1. Acoustic black holes can achieve vibration reduction requirements. The variable thickness area of ​​the black hole must satisfy a certain mathematical function, and additional damping material must be attached. However, the disadvantage is that it is difficult to install and has a large additional mass.

[0005] 2. Nonlinear energy sinks have the property of unidirectional transmission of vibration energy and usually adopt the structure of nonlinear springs, dampers and mass blocks. The disadvantage is that dampers need to be added, which results in large additional mass.

[0006] 3. The active control method of sticking piezoelectric materials on the surface of the wall panel also has the disadvantages of being difficult to implement and having unsatisfactory control effects.

[0007] Therefore, a device or method for suppressing aircraft panel flutter with a simple structure and low implementation difficulty is needed to solve the above technical problems. Summary of the Invention

[0008] In order to solve the above technical problems, the present invention adopts a combined structure of a linear spring and coherent friction between a moving contact and a static contact. The linear spring is placed at an angle, and the inclined spring generates nonlinear force components in the horizontal and vertical directions respectively. The nonlinear force component in the vertical direction provides a nonlinear force for the wall panel flutter, and the nonlinear force component in the horizontal direction acts on the moving contact, forming a nonlinear positive pressure between the moving and static contacts, so that the dry friction between the moving and static contacts also presents nonlinearity. Utilizing the principle of dry friction equivalent viscous damping, the nonlinear dry friction between the moving and static contacts can be equivalent to nonlinear equivalent viscous damping, which provides damping energy dissipation for the wall panel flutter. The present invention realizes the flutter suppression of the wall panel from two aspects: providing nonlinear force to improve the supporting structure of the wall panel and introducing nonlinear dry friction to improve damping energy dissipation and vibration reduction.

[0009] The present invention provides the following technical solution: a passive nonlinear energy-dissipating control structure for suppressing flutter of an aircraft panel, comprising: a linear stiffness spring, a moving contact, and a static contact; one end of the linear stiffness spring is connected to the inner wall of the aircraft panel, the other end of the linear stiffness spring is connected to the moving contact, the moving contact is slidably connected to the static contact, and the static contact is fixedly connected to the aircraft frame;

[0010] There is Coulomb friction between the moving contact and the static contact;

[0011] An angle is provided between a line connecting two ends of the linear stiffness spring and a vertical line of the wall plate.

[0012] Preferably, the sliding direction of the movable contact slidingly connected to the static contact is parallel to the wall panel or perpendicular to the wall panel.

[0013] Preferably, the angle between the line connecting the two ends of the linear stiffness spring and the perpendicular line of the wall panel is θ;

[0014] When the sliding direction of the moving contact slidingly connecting the static contact is parallel to the wall plate, the value range of the angle θ is: 45°≤θ≤80°;

[0015] When the sliding direction of the moving contact to slide and connect the static contact is perpendicular to the wall plate, the value range of the angle θ is: 10°≤θ≤60°.

[0016] Preferably, the connection mode of the linear stiffness spring to the inner side wall of the wall panel includes: the linear stiffness spring fixedly connects the inner side wall of the wall panel, the linear stiffness spring hingedly connects the inner side wall of the wall panel, and the linear stiffness spring rotatably connects the inner side wall of the wall panel.

[0017] Preferably, a limiting device is provided on the static contact, and the limiting device is used to limit the sliding stroke of the moving contact slidingly connecting with the static contact.

[0018] The present invention also discloses a passive nonlinear energy dissipation control method for suppressing flutter of aircraft panels. The passive nonlinear energy dissipation control method is used for the above-mentioned passive nonlinear energy dissipation control structure. The passive nonlinear energy dissipation control method includes the following steps:

[0019] Step 1: Establish an equivalent mechanical model of the passive nonlinear energy dissipation structure;

[0020] Step 2, equivalent nonlinear stiffness;

[0021] Step 3, equivalent nonlinear viscous damping;

[0022] Step 4: Establish an equivalent mechanical model of a four-side clamped wall panel with a passive nonlinear energy dissipation structure;

[0023] Step 5: Establish a simplified calculation model of the nonlinear equivalent viscous damping of the passive nonlinear energy dissipation structure in the clamped wall panel;

[0024] Step 6: Determine the installation position and quantity of the passive nonlinear energy dissipation structure in the wall panel.

[0025] Preferably, in step 1, the components of force generated by the linear stiffness spring of the equivalent mechanical model in the X and Z directions are respectively:

[0026]

[0027] In formula (1) and formula (2), k s represents the stiffness of the linear stiffness spring, l0 represents the length of the linear stiffness spring in the free state, θ represents the angle between the linear stiffness spring and the Z direction, l represents the distance between the upper connection end of the linear stiffness spring and the moving contact in the X direction, z represents the distance between the wall panel and the frame in the Z direction, and z represents the variable that vibrates with the wall panel when the wall panel vibrates.

[0028] More preferably, in step 2, the equivalent nonlinear stiffness is:

[0029] F Z =k1z+k3z 3 (4)

[0030] In formula (4), k1 = 2k s (1-l0 / l), k3=k s l0 / l 3 ;

[0031] In step 3, the equivalent nonlinear viscous damping is:

[0032]

[0033] In formula (6), c erepresents the equivalent viscous damping, μ represents the friction coefficient, N represents the normal pressure between the friction contact surfaces, ω represents the vibration frequency of the structure, and B represents the amplitude of the structure.

[0034] More preferably, in step 5, the nonlinear equivalent viscous damping of the simplified calculation model can be expressed as:

[0035]

[0036] In formula (14) and formula (15), I represents the moment of inertia of the section; k non represents the nonlinear stiffness of the passive nonlinear energy dissipation structure, (x ai ,y bi ) represents the support position, w=w(x,y) represents the panel displacement function, Δp represents the static pressure distribution in the cavity, pp ∞ Indicates pneumatic pressure.

[0037] Preferably, the step 6 specifically includes: generating a nonlinear force F according to the passive nonlinear energy dissipation structure Z and nonlinear equivalent viscous damping c e-non , combined with the vibration frequency ω of the wall panel and the section inertia moment I, the linear stiffness spring stiffness k is obtained s , parameter l, original length of linear stiffness spring l0, installation position (x ai ,y bi ), thereby selecting the linear stiffness spring parameters and installation position.

[0038] The beneficial effects of the present invention are:

[0039] 1. The present invention combines a linear stiffness spring with a Coulomb friction slider. When an aircraft panel vibrates, the linear stiffness spring nonlinearly transfers the panel vibration to the Coulomb friction slider for energy consumption, and the slider acts as a damper to suppress the panel vibration. The present invention uses reliable and commonly used springs and Coulomb friction sliders to achieve vibration suppression. Therefore, the present invention has a simple structure, low implementation difficulty, high reliability, and low implementation cost.

[0040] 2. In the present invention, when the wall panel flutters, the upper connecting end of the linear stiffness spring vibrates up and down in the Z direction along with the wall panel. Since the lower connecting end and the moving contact are subjected to Coulomb friction in the Z direction, the linear stiffness spring will be compressed or stretched. The linear stiffness spring is placed at an angle, and the upper connecting end of the linear stiffness spring generates component forces in the X and Z directions respectively. Similarly, the lower connecting end of the linear stiffness spring also generates component forces in the X and Z directions of the moving contact respectively, which are equal in magnitude and opposite in direction to those of the upper connecting end. Therefore, the present invention has a better effect in suppressing the flutter of the aircraft wall panel.

[0041] 3. The nonlinear equivalent viscous damping of the passive nonlinear energy dissipation structure of the present invention is a nonlinear function of multiple parameters, including the linear spring stiffness, parameters, original spring length, installation location, panel vibration frequency, and section moment of inertia. At each installation location, the passive nonlinear energy dissipation structure of the present invention generates both nonlinear forces and nonlinear equivalent viscous damping, which together help suppress panel flutter. Therefore, the modeling method of the present invention facilitates research on passive flutter control of aircraft panel structures and can effectively simulate the passive flutter control characteristics of spacecraft panel structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 Schematic diagram of the passive nonlinear energy dissipation control structure and method for suppressing aircraft panel flutter according to the present invention;

[0043] Figure 2 Schematic diagram of the equivalent mechanical model of the passive nonlinear energy dissipation structure of the present invention;

[0044] Figure 3 It is a schematic diagram of the connection structure of the present invention;

[0045] Figure 4 is a schematic diagram of the installation position of the wall panel according to an embodiment of the present invention;

[0046] Figure 5 is a schematic diagram of the deformation of the wall panel of the present invention after flutter;

[0047] Figure 6 Schematic diagram of an equivalent mechanical model of a passive nonlinear energy dissipation structure wall panel according to the present invention;

[0048] Figure 7 It is a schematic diagram of a wall panel model in a high-speed airflow according to the present invention.

[0049] In the figure, 1. linear stiffness spring; 2. moving contact; 3. static contact; 4. frame; 5. wall panel; 6. rivet; 7. cavity; 8. limit device. DETAILED DESCRIPTION

[0050] The following will provide a clear and complete description of the relevant technologies in the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0051] like Figures 1 to 7As shown, the passive nonlinear energy dissipation structure for suppressing aircraft panel flutter in this embodiment is simple in structure and easy to implement. This embodiment utilizes nonlinear vibration theory to suppress panel flutter by adding nonlinear elastic supports and providing nonlinear dry friction energy dissipation.

[0052] 1. Passive nonlinear energy dissipation structure

[0053] The passive nonlinear energy dissipation structure of this embodiment is composed of a linear stiffness spring 1, a moving contact 2 and a static contact 3. The schematic diagram of the structure is shown in FIG. Figure 1 shown.

[0054] Figure 1 In the figure, the upper connecting end of the linear stiffness spring 1 is fixedly connected to the wall plate 5, and the lower connecting end is fixedly connected to the moving contact 2. The moving contact 2 and the static contact 3 are connected by sliding, and the two always keep in contact. There is Coulomb friction between them, and the friction coefficient is μ. The static contact 3 is fixed on the frame 4. In order to prevent the moving contact 2 from separating from the static contact 3, a limit device 8 is provided at the end of the static contact 3.

[0055] When the wall panel 5 vibrates, the upper connection end of the linear stiffness spring 1 vibrates up and down along with the wall panel 5 in the Z direction. Due to the Coulomb friction between the lower connection end and the moving contact 2 in the Z direction, the linear stiffness spring 1 is compressed or stretched. Since the linear stiffness spring 1 is placed at an angle, the upper connection end of the linear stiffness spring 1 generates a component force F in the X direction and the Z direction respectively. X and F Z Similarly, the lower connection end of the linear stiffness spring 1 also generates F in the X direction and Z direction of the moving contact 2. X and F Z Equal and opposite force components.

[0056] 2. Equivalent mechanical model of passive nonlinear energy dissipation structure

[0057] The equivalent mechanical model of passive nonlinear energy dissipation structure is as follows Figure 2 As shown, k non is the equivalent nonlinear stiffness, c e-non is the nonlinear equivalent viscous damping.

[0058] When the wall plate 5 vibrates, the upper connection end of the linear stiffness spring 1 vibrates up and down along with the wall plate 5 in the Z direction, causing the lower connection end of the linear stiffness spring 1 and the moving contact 2 to slide slightly back and forth relative to the static contact 3 in the Z direction. Figure 1 , the forces generated by the linear stiffness spring 1 in the X and Z directions are

[0059]

[0060] Among them, k sis the stiffness of the linear stiffness spring 1, l0 is the length of the linear stiffness spring 1 in the free state, θ is the angle between the linear stiffness spring 1 and the Z direction, l is the distance between the upper connection end of the linear stiffness spring 1 and the moving contact 2 in the X direction, and z is the distance between the wall panel 5 and the frame 4 in the Z direction. When the wall panel 5 vibrates, z becomes a variable that vibrates with the wall panel 5. When the moving contact 2 slides horizontally back and forth relative to the static contact 3, the value range of θ is preferably 45°≤θ≤60°; when the moving contact 2 slides vertically back and forth relative to the static contact 3, the value range of θ is preferably 30°≤θ≤60°.

[0061] In order to suppress the vibration of the wall panel 5, the passive nonlinear energy dissipation structure of this embodiment has two functions: (1) the upper connection end of the linear stiffness spring 1 is connected to the wall panel 5, and during the vibration of the wall panel 5, a nonlinear force F is provided to suppress the vibration of the wall panel 5. Z ;(2)F X When applied to the moving contact 2, reciprocating dry friction occurs between the moving contact 2 and the static contact 3. The reciprocating dry friction motion has an energy-consuming effect, providing a damping effect for the suppression of chatter.

[0062] 2.1 Equivalent nonlinear stiffness

[0063] Perform Taylor expansion on equation (2) and take the first two terms, then equation (2) becomes

[0064] F Z =2k s (1-l0 / l)z+k s l0 / l 3 z 3 (3)

[0065] Or abbreviated as

[0066] F Z =k1z+k3z 3 (4)

[0067] or

[0068] F Z =k non z=(k1+k3z 2 )z (5)

[0069] Where k1 = 2k s (1-l0 / l), k3=k s l0 / l 3 Obviously, formula (3) is a nonlinear function of the flutter displacement z of the wall panel 5. Since the cubic power of displacement z appears in formula (3), it means that the larger the displacement z, the greater the nonlinear force applied to the wall panel.

[0070] 2.2 Equivalent nonlinear viscous damping

[0071] According to the equivalence principle of energy method in vibration dynamics, Coulomb friction (dry friction) can be equivalent to the viscous damping coefficient, that is,

[0072]

[0073] Among them, c e is the equivalent viscous damping, μ is the friction coefficient, N is the normal pressure between the friction contact surfaces, ω is the vibration frequency of the structure (in this embodiment, it is the vibration frequency of the wall panel), and B is the amplitude of the structure (in this embodiment, it can be replaced by the vibration displacement w of the wall panel).

[0074] 3. Installation location and number of passive nonlinear energy dissipation structures in the wall panel

[0075] The actual engineering structure of aircraft panels mostly adopts riveted connection structure, which is usually simplified as follows in the theoretical study of aeroelastic dynamics of panels: Figure 3 (a) shows a schematic diagram of the connection structure. After the wall plate 5 and the frame 4 are riveted together with rivets 6, a cavity 7 is formed between the two. From the perspective of mechanical modeling, Figure 3 The wall panel with riveted connection structure shown in (a) can be simplified into a mechanical model of a four-side clamped plate, as shown in Figure 3 (b) shown.

[0076] In order to facilitate viewing of the installation position of the device in the wall panel in this embodiment, it is assumed that the wall panel is transparent and two energy consuming devices are used as an example for explanation. Figure 4 As shown, control Figure 3 From the perspective of this embodiment, the device is installed in Figure 3 In the hollow cavity 7.

[0077] Figure 4 In this embodiment, the upper connection end of the passive nonlinear energy dissipation structure is connected to the lower surface of the wall panel 5, the lower connection end of the passive nonlinear energy dissipation control structure is connected to the dynamic contact point 2, and the static contact point 3 is connected to the frame 4. The dynamic contact point 2 and the static contact point 3 always maintain dry friction contact. This embodiment is described by taking the installation of two vibration suppression devices as an example. The two passive nonlinear energy dissipation structures of this embodiment are respectively installed at (a / 3, b / 2) and (2a / 3, b / 2) of the wall panel. Figure 4 shown.

[0078] 4. Equivalent Mechanical Model of a Four-Sided Clamped Panel with Passive Nonlinear Energy Dissipation Structure

[0079] The schematic diagram of the deformation of the wall panel 5 after vibration is as follows: Figure 5 As shown, Figure 5In the example, due to the structural limitations of the moving contact 2 and the static contact 3, the moving contact 2 can only slide back and forth along the Z direction. After the wall plate 5 vibrates and deforms, the wall plate 5 drives the upper connection end of the linear stiffness spring 1 to move up and down, and the linear stiffness spring 1 is stretched / compressed. At the same time, the lower connection end of the linear stiffness spring 1 and the moving contact 2 and the static contact 3 slide back and forth in dry friction. Figure 2 The equivalent mechanical model of the passive nonlinear energy dissipation structure wall is as follows: Figure 6 shown.

[0080] 5. Simplified Calculation Model of Nonlinear Equivalent Viscous Damping of Passive Nonlinear Energy Dissipation Structure in Clamped Panels

[0081] Taking the installation of two passive nonlinear energy dissipation structures as an example, the wall panel model in high-speed airflow is as follows: Figure 7 As shown, the installation position of the passive nonlinear energy dissipation structure is referenced to Figure 4 (a).

[0082] Based on the two-dimensional wall panel motion equation, the three-dimensional wall panel motion differential equation can be obtained.

[0083]

[0084] and deformation compatibility equations

[0085]

[0086] Among them, w = w(x, y) is the displacement function of the wall panel, Φ = Φ(x, y) is the stress function, and The internal and external forces in the x and y directions, Δp is the static pressure distribution in the cavity, h is the thickness of the wall, D = Eh 3 / 12(1-ν 2 ), E is the Young's modulus of elasticity of the panel material, ν is the Poisson's ratio, pp ∞ is the pneumatic pressure, ρ m is the density of the wall panel material, F non Nonlinear external forces introduced for passive nonlinear energy dissipation structures.

[0087] In order to facilitate the solution, the Galekin method is usually used to transform the three-dimensional wall plate motion differential equation (7) and deformation coordination equation (8) into a set of ordinary differential equations. The Galekin function is taken as a double sine function, that is,

[0088]

[0089] Equations (7) and (8) are coupled with each other, and the solution process is complicated, making it difficult to obtain an analytical solution. Numerical solutions are more suitable for studying the influence of parameters.

[0090] The variation curve of the wall panel vibration displacement w = w(x, y) can be obtained by equations (7) to (9). Further, according to the equivalent viscous damping expression (6), the simplified expression for the nonlinear equivalent viscous damping calculation of this embodiment can be obtained, that is,

[0091]

[0092] According to the nonlinear vibration theory of the plate, the vibration of the wall panel 5 under supersonic airflow is a typical fluid-solid coupling vibration. Its dynamic mathematical model is a nonlinear partial differential equation. The vibration frequency ω of the wall panel 5 is related to the cross-sectional inertia moment I and the nonlinear stiffness k of the passive nonlinear energy dissipation structure. non and support position (x ai ,y bi ) and other parameters, namely

[0093] ω=ω(I,k non ,x ai ,y bi ) x ai ∈(0,a),y bi ∈(0,b) (11)

[0094] In addition, the vibration displacement of the wall panel 5 is also related to the parameters of the wall panel structure, aerodynamic pressure, static pressure distribution in the cavity, etc. The vibration displacement of the wall panel 5 at the first installation position can be simplified into a functional expression, that is,

[0095] w1(a / 3,b / 2)=w(ω,I,pp ∞ ,Δp,a / 3,b / 2) (12)

[0096] The vibration displacement of the wall panel 5 at the second installation position can be simplified into a functional expression, that is,

[0097] w2(2a / 3,b / 2)=w(ω,I,pp ∞ ,Δp,2a / 3,b / 2) (13)

[0098] Therefore, the nonlinear equivalent viscous damping generated by the passive nonlinear energy dissipation structure of this embodiment at the two positions can be expressed as follows:

[0099]

[0100] The nonlinear equivalent viscous damping of the passive nonlinear energy dissipation structure of this embodiment is the linear spring stiffness k s , parameter l, original length of spring l0, installation position (x ai ,y bi), the vibration frequency ω of the wall panel, the section moment of inertia I and other nonlinear functions. At each installation position, the passive nonlinear energy dissipation structure of this embodiment can generate a nonlinear force F Z and nonlinear equivalent viscous damping c e-non , the two together help to suppress the wall panel flutter.

[0101] In summary, the present invention combines a linear stiffness spring with a Coulomb friction slider so that when an aircraft panel flutters, the linear stiffness spring nonlinearly transfers the panel flutter to the Coulomb friction slider for energy consumption, and the slider acts as a damper to suppress the panel flutter; the present invention uses reliable and commonly used springs and Coulomb friction sliders to achieve flutter suppression, so the present invention has a simple structure, low implementation difficulty, high reliability, and low implementation cost.

[0102] It should be emphasized that the above are only preferred embodiments of the present invention and do not limit the present invention in any form. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A passive nonlinear energy dissipation control method for suppressing aircraft panel flutter, characterized in that: The following steps are involved: Step 1: Establish an equivalent mechanical model of the passive nonlinear energy dissipation structure; Step 2, equivalent nonlinear stiffness; Step 3, equivalent nonlinear viscous damping; Step 4: Establish an equivalent mechanical model of a four-side clamped wall panel with a passive nonlinear energy dissipation structure; Step 5: Establish a simplified calculation model of the nonlinear equivalent viscous damping of the passive nonlinear energy dissipation structure in the clamped wall panel; Step 6: Determine the installation position and quantity of the passive nonlinear energy dissipation structure in the wall panel; The passive nonlinear energy dissipation control structure of the passive nonlinear energy dissipation control method comprises: a linear stiffness spring (1), a moving contact (2), and a static contact (3); one end of the linear stiffness spring (1) is connected to the inner wall of a wall panel (5) of an aircraft, the other end of the linear stiffness spring (1) is connected to the moving contact (2), the moving contact (2) is slidably connected to the static contact (3), and the static contact (3) is fixedly connected to a frame (4) of the aircraft; Coulomb friction exists between the moving contact (2) and the static contact (3); An angle is provided between a line connecting the two ends of the linear stiffness spring (1) and a vertical line of the wall plate (5).

2. The passive nonlinear energy dissipation control method for suppressing aircraft panel flutter according to claim 1, characterized in that: The sliding direction of the moving contact (2) in sliding connection with the static contact (3) is parallel to the wall plate (5) or perpendicular to the wall plate (5).

3. The passive nonlinear energy dissipation control method for suppressing aircraft panel flutter according to claim 1, characterized in that: The angle between the connecting line of the two ends of the linear stiffness spring (1) and the vertical line of the wall plate (5) is θ; When the sliding direction of the movable contact (2) slidingly connected to the static contact (3) is parallel to the wall plate (5), the value range of the angle θ is: 45°≤θ≤80°; When the sliding direction of the movable contact (2) in sliding connection with the static contact (3) is perpendicular to the wall plate (5), the value range of the angle θ is: 10°≤θ≤60°.

4. The passive nonlinear energy dissipation control method for suppressing aircraft panel flutter according to claim 1, characterized in that: The connection modes of the linear stiffness spring (1) to the inner side wall of the wall panel (5) include: the linear stiffness spring (1) is fixedly connected to the inner side wall of the wall panel (5), the linear stiffness spring (1) is hingedly connected to the inner side wall of the wall panel (5), and the linear stiffness spring (1) is rotatably connected to the inner side wall of the wall panel (5).

5. The passive nonlinear energy dissipation control method for suppressing aircraft panel flutter according to claim 1, characterized in that: A limiting device (8) is provided on the static contact (3), and the limiting device (8) is used to limit the sliding stroke of the moving contact (2) in sliding connection with the static contact (3).

6. The passive nonlinear energy dissipation control method for suppressing aircraft panel flutter according to claim 1, characterized in that: In step 1, the components of force generated by the linear stiffness spring of the equivalent mechanical model in the X and Z directions are: (1) (2) In formula (1) and formula (2), represents the stiffness of the linear stiffness spring, represents the length of the linear stiffness spring in the free state, represents the angle between the linear stiffness spring and the Z direction, Indicates the distance between the upper connection end of the linear stiffness spring and the moving contact in the X direction, Indicates the distance between the wall plate and the frame in the Z direction, A variable that indicates the vibration of the panel when the panel vibrates.

7. The passive nonlinear energy dissipation control method for suppressing aircraft panel flutter according to claim 6, characterized in that: In step 2, the equivalent nonlinear stiffness is: (4) In formula (4), , ; In step 3, the equivalent nonlinear viscous damping is: (6) In formula (6), represents the equivalent viscous damping, represents the friction coefficient, Indicates the normal pressure between the friction contact surfaces, represents the vibration frequency of the structure, Indicates the amplitude of the structure.

8. The passive nonlinear energy dissipation control method for suppressing aircraft panel flutter according to claim 7, characterized in that: In step 5, the nonlinear equivalent viscous damping of the simplified calculation model can be expressed as: (14) (15) In formula (14) and formula (15), represents the moment of inertia of the section; represents the nonlinear stiffness of the passive nonlinear energy dissipation structure, Indicates support location, represents the panel displacement function, represents the static pressure distribution in the cavity, Indicates pneumatic pressure.

9. The passive nonlinear energy dissipation control method for suppressing aircraft panel flutter according to claim 1, characterized in that: The step 6 specifically includes: generating a nonlinear force according to the passive nonlinear energy dissipation structure. and nonlinear equivalent viscous damping , combined with the vibration frequency of the wall panel , Sectional moment of inertia , the linear stiffness spring stiffness is obtained ,parameter , original length of linear stiffness spring , Installation location , thereby selecting the linear stiffness spring parameters and installation position.

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