An adaptive granular damping device

Abstract

This invention provides an adaptive particle damping device, belonging to the field of structural vibration and noise control technology. It includes a damper housing, on which multiple variable-structure damping units are installed on the bottom wall. One end of each variable-structure damping unit is rotatably connected to the inner sidewall of the damper housing, while the other end can swing. The damper housing is filled with a particle composite medium. This invention pioneers a biomimetic variable-structure mechanism, introducing the principle of adaptive morphological changes in bird wings into the design of the particle damping cavity, breaking the traditional static and fixed technical convention of cavities. Through a rigid-flexible segmented fin, it achieves a dual-degree-of-freedom composite deformation of "rotation + extension," constructing an autonomous closed loop of "vibration excitation—fin deformation—cavity reconstruction—energy dissipation mechanism adaptation," solving the core bottleneck that fixed-parameter dampers cannot adapt to complex and variable environments.

Description

Technical Field

[0001] This invention relates to the field of structural vibration and noise control technology, and in particular to an adaptive particle damping device. Background Technology

[0002] Traditional particle damping devices typically consist of simply filling structural cavities with particles, dissipating vibrational energy through particle collisions and friction. The damping characteristics of such structures are fixed and unchanging, making them ill-suited to complex and variable real-world vibration environments. Existing particle damping devices based on particle parameter optimization rely on discrete element simulations under preset operating conditions, lacking the ability to adapt to real-time changes in environmental excitation. Torsional particle damping devices are structurally complex, requiring precise design and calculation, resulting in high manufacturing costs and difficulties in maintenance. Currently, there is no adaptive particle damping structure capable of autonomously adjusting the cavity structure based on vibration intensity to alter particle motion and energy dissipation mechanisms. Summary of the Invention

[0003] This invention provides an adaptive particle damping device. Existing technologies suffer from the following problems: the damping characteristics of traditional particle damping devices are fixed and unchanging, making it difficult to adapt to complex and ever-changing actual vibration environments; particle damping devices with optimized particle parameters lack the ability to adapt to real-time changes in environmental excitation; and torsional particle damping devices have complex structures and high manufacturing costs.

[0004] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0005] An adaptive particle damping device includes a damper housing, on which a plurality of variable-structure damping units are installed. One end of each variable-structure damping unit is rotatably connected to the inner sidewall of the damper housing, and the other end of each variable-structure damping unit is oscillating. The damper housing is filled with a particle composite medium.

[0006] Optionally, the variable-structure damping unit includes a variable-structure damping shell and an elastic reset member. One end of the variable-structure damping shell is rotatably connected to the inner wall of the damper housing, the bottom of the variable-structure damping shell is connected to one end of the elastic reset member, and the other end of the elastic reset member is connected to the bottom inner wall of the damper housing.

[0007] Optionally, the variable-structure damping unit is provided with an end rigid body section.

[0008] Optionally, the outer wall of the end rigid body segment is fixedly connected to the middle elastic body segment.

[0009] Optionally, a root rigid body segment is fixedly connected to the outer wall of the middle elastic body segment, and the bottom of the root rigid body segment is fixedly connected to the top of the elastic reset member.

[0010] Optionally, the variable-structure damping housing is provided with a pivot shaft, which is hinged to the side wall of the damper housing.

[0011] Optionally, the variable-structure damping units are arranged in an array along the length of the damper housing.

[0012] Optionally, the central elastic body segment is made of flexible memory sheet material, and slots are provided on both sides.

[0013] Optionally, the root rigid body segment is made of metal.

[0014] Optionally, the elastic reset member is made of metal, and it has symmetrically distributed weakening parts at its middle position, with the weakening parts protruding outwards.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects:

[0016] The above-mentioned solution pioneered a biomimetic deformation mechanism, introducing the principle of adaptive morphological changes in bird wings into the design of particle damping cavities, breaking the traditional static and fixed technical paradigm of cavities. By using segmented fins that combine rigidity and flexibility to achieve "rotation + extension" dual-degree-of-freedom composite deformation, an autonomous closed loop of "vibration excitation - fin deformation - cavity reconstruction - energy dissipation mechanism adaptation" is constructed, solving the core bottleneck that fixed-parameter dampers cannot adapt to complex and variable environments.

[0017] This invention relies entirely on environmental vibration energy for driving, and its purely mechanical structure realizes the entire process of "sensing-response-regulation" without the need for external power, sensors, controllers, or human intervention.

[0018] To overcome the blind zone of low-frequency micro-amplitude vibration response, a segmented fin combining rigidity and flexibility is adopted. The elastic body segment can still undergo micro-expansion / bending vibration under extremely low excitation, continuously disturbing the particulate medium and improving the vibration reduction effect of low-frequency micro-amplitude vibration.

[0019] This invention utilizes a multi-mechanism synergistic broadband energy dissipation approach. It real-time allocates the weights of frictional and collision energy dissipation within a modified cavity, combining density gradient particles with a non-Newtonian fluid composite medium to introduce viscous energy dissipation and viscoelastic internal friction of the elastomer. These mechanisms work synergistically across multiple frequency bands, significantly improving vibration reduction and noise reduction performance under combined low-frequency resonance and high-frequency micro-vibration conditions. Attached Figure Description

[0020] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate embodiments of the invention and, together with the specification, further serve to explain the principles of the invention and enable those skilled in the art to practice and use the invention.

[0021] Figure 1 A three-dimensional cross-sectional view of the adaptive particle damping device;

[0022] Figure 2 A three-dimensional enlarged structural schematic diagram of the variable-structure damping unit and the elastic reset element;

[0023] Figure 3 for Figure 2 Enlarged view of the 3D structure at point A in the middle;

[0024] Figure 4 A three-dimensional structural diagram of the internal structure of the adaptive particle damping device.

[0025] Figure 5 A three-dimensional structural diagram of an adaptive particle damping device under low-intensity vibration conditions.

[0026] Figure 6 A three-dimensional structural diagram of an adaptive particle damping device under high-intensity vibration conditions.

[0027] Figure 7 This is a schematic diagram of the three-dimensional structure of density gradient particles;

[0028] Figure 8 This is a schematic diagram of a non-Newtonian fluid-particle composite structure.

[0029] Figure 9 This is a schematic diagram of the vibration acceleration effect of a particle damper.

[0030] Figure label:

[0031] 1. Damper housing; 2. Variable structure damping housing; 3. End rigid body section; 4. Middle elastic body section; 5. Root rigid body section; 6. Elastic reset component; 7. Weakening part; 8. Slot.

[0032] As shown in the figure, specific structures and devices are marked in the figure to clearly illustrate the structure of the embodiments of the present invention. However, this is only for illustrative purposes and is not intended to limit the present invention to this specific structure, device and environment. Those skilled in the art can adjust or modify these devices and environments according to specific needs. Detailed Implementation

[0033] The adaptive particle damping device provided by the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, to make the embodiments more detailed, the following embodiments are the best and preferred embodiments, and those skilled in the art can use other alternative methods to implement some known technologies; moreover, the accompanying drawings are only for more specific description of the embodiments and are not intended to specifically limit the present invention.

[0034] It should be noted that the use of terms such as "an embodiment," "an embodiment," "an exemplary embodiment," and "some embodiments" in the specification indicates that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments (whether explicitly described or not) should be within the knowledge of those skilled in the art.

[0035] Generally, terms can be understood at least partly from their use in context. For example, depending at least partly on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in a singular sense, or a combination of features, structures, or characteristics in a plural sense. Additionally, the term "based on" can be understood not necessarily to convey an exclusive set of factors, but rather, alternatively, depending at least partly on the context, to allow for the presence of other factors that are not necessarily explicitly described.

[0036] It is understood that the meanings of “on”, “above”, and “above” in this invention should be interpreted in the broadest manner, such that “on” means not only “directly on” something, but also includes the meaning of being “on” something with an intervening feature or layer, and that “above” or “above” means not only “on” something, but also includes the meaning of being “on” something without an intervening feature or layer.

[0037] Furthermore, spatially related terms such as “below,” “under,” “lower,” “above,” and “upper” are used herein for convenience to describe the relationship of one element or feature to one or more other elements or features, as illustrated in the accompanying drawings. Spatially related terms are intended to cover different orientations in the use or operation of the device other than those depicted in the accompanying drawings. The device may be oriented in other ways, and the spatially related descriptive terms used herein can be interpreted similarly.

[0038] like Figures 1 to 8As shown, an embodiment of the present invention provides an adaptive particle damping device, including a damper housing 1. Multiple variable-structure damping units are installed on the bottom wall inside the damper housing 1. One end of the variable-structure damping unit is rotatably connected to the inner side wall of the damper housing 1, and the other end of the variable-structure damping unit can swing. The damper housing 1 is filled with a particle composite medium. The variable-structure damping units are arrayed along the length direction of the damper housing 1. The variable-structure damping unit can also be called a fin. In the following detailed description, the variable-structure damping unit is referred to as a fin. There are five groups of fins, which are evenly distributed in the inner wall of the damper housing 1. A large amount of particle composite medium is placed inside the damper housing 1 for the adaptive function of the fins.

[0039] like Figure 2 As shown, the variable-structure damping unit includes a variable-structure damping shell 2 and an elastic reset member 6. One end of the variable-structure damping shell 2 is rotatably connected to the inner wall of the damper housing 1, and the bottom of the variable-structure damping shell 2 is connected to one end of the elastic reset member 6. The other end of the elastic reset member 6 is connected to the bottom inner wall of the damper housing 1. The variable-structure damping unit is provided with an end rigid body section 3. A middle elastic body section 4 is fixedly connected to the outer wall of the end rigid body section 3. A root rigid body section 5 is fixedly connected to the outer wall of the middle elastic body section 4. The bottom of the root rigid body section 5 is fixedly connected to the top of the elastic reset member 6. The middle elastic body section 4 is a flexible section. The material is thin sheet, and there are slots 8 on both sides. The root rigid body section 5 is made of metal, and the elastic reset member 6 is made of metal. There are symmetrically distributed weakening parts 7 in the middle position. The structure of the weakening part 7 protrudes outward. The variable structure damping shell 2 is provided with a rotating shaft, which is hinged to the side wall of the damper shell 1. The root rigid body section 5 is made of metal, and the outer wall of the root rigid body section 5 away from the middle elastic body section 4 is provided with a rotating shaft, which is consistent with the structure of the variable structure damping shell 2 mentioned above. The elastic reset member 6 is made of metal, and there are two layers of weakening parts 7 in the middle. The structure of the weakening part 7 protrudes outward.

[0040] The structure and working principle of fins:

[0041] Each fin, resembling a bird's coverts, is hinged to the side wall of the damper housing 1 via a pivot. The multiple fins are arranged parallel to each other along the vibration transmission direction (or the main direction of noise propagation), forming a stacked structure. An elastic reset member 6 provides a restoring torque for each fin; either a shape memory alloy spring or a spring sheet can be used. In this invention, a shape memory alloy spring sheet is used. This spring sheet connects the back of the fin (the non-vibration-facing surface) to the damper housing 1, setting the initial tilt angle of the fin (e.g., closed or slightly open) and providing a restoring force that increases with deformation.

[0042] The specific process of fin adaptive deformation can be divided into three cases, such as... Figures 3 to 5 and Figure 8As shown, in low-intensity vibration conditions: when the amplitude of the external vibration excitation is small and the torque acting on the fins is insufficient to overcome the preset torque of the elastic reset component 6, the fin assembly maintains its initial compact configuration. At this time, there is little mutual interaction between the fin assembly and the particle composite medium. The particle composite medium mainly exhibits rolling and sliding friction. The system exhibits characteristics of high stiffness and medium-high damping (mainly due to frictional energy dissipation), and is good at suppressing high-frequency micro-amplitude vibrations and noise.

[0043] like Figure 4 As shown, under high-intensity vibration conditions: when the amplitude of the external vibration excitation increases, and the torque acting on the fin is sufficient to overcome and exceed the torque of the elastic reset member 6, the fin will rotate around the axis of rotation, and the direction of rotation will follow... Figure 4 The middle part is a counterclockwise rotation and unfolding process, which is directly driven by vibration energy. As the fins unfold, the bottom area of ​​the inner wall of the profile cavity increases, thereby increasing the effective volume of the particle composite medium inside the profile cavity. The degree of freedom of motion and acceleration space obtained by the particle composite medium increases significantly, and the probability of violent collisions between particles increases dramatically. The system characteristics change to lower stiffness and higher damping (mainly energy dissipation through collision), thus efficiently dissipating large-amplitude low-frequency vibration energy.

[0044] Dynamic adaptation: Once the vibration intensity weakens, the elastic reset component 6 drives the fins to recover, and the system configuration and damping characteristics are also restored. The whole process constitutes a purely mechanical "sensing-response" closed loop directly driven by vibration excitation.

[0045] To further improve the response sensitivity and energy dissipation capacity of the fins under low-frequency, low-amplitude vibration conditions, this invention has carried out a biomimetic design of the fin structure itself. Inspired by the rigid support and flexible bending characteristics of bird flight feather shafts, a segmented fin structure combining rigidity and flexibility is proposed.

[0046] Each fin consists of three sub-segments connected in series: a root rigid body segment 5, a middle elastic body segment 4, and an end rigid body segment 3. The root rigid body segment 5 is made of metal or engineering plastic and is hinged to the damper housing 1 via a pivot and connected to an elastic reset element 6, which is responsible for transmitting the rotational driving torque. The middle elastic body segment 4 is made of a highly elastic, low-hysteresis material (such as natural rubber, polyurethane elastomer, or flexible shape memory alloy sheet), and its geometry can be a sheet, a bellows, or a honeycomb sandwich structure, allowing for controllable tensile, compressive, or bending deformation in the axial direction. The end rigid body segment 3 is also made of a rigid material, and its geometry can be designed as a flat plate, an arc-shaped airfoil, or a toothed structure with turbulence, depending on the energy consumption requirements.

[0047] Under external vibration excitation, the segmented fins can achieve coordinated deformation of "rotation + extension". Controlled by the root shaft and the elastic reset component 6, it responds to medium and high intensity vibration excitation and achieves large-amplitude opening and closing action. The middle elastic body segment 4 provides independent support. Even when the vibration amplitude is extremely low and insufficient to overcome the pre-tightening force of the root spring, the elastic body segment can still undergo slight axial extension or bending, causing the end rigid body segment 3 to undergo local displacement, thereby disturbing the packing density, flow path and contact force chain of the particulate composite medium.

[0048] Traditional rigid fins remain completely stationary at low amplitudes, and the particle composite medium relies solely on its own micro-motion to dissipate energy, resulting in low efficiency. This invention introduces an elastomer segment, expanding the original "all-or-nothing" rotational triggering mechanism into a continuous and progressive flexible deformation response. Even in scenarios where trains are running smoothly and environmental micro-vibrations dominate, the segmented fins can still generate high-frequency, small-amplitude elastic vibrations with an extremely low excitation threshold, continuously disturbing the particle bed. This transforms the simple energy dissipation from inter-particle friction into a composite mechanism of "particle-fin dynamic contact friction" and "elastic viscoelastic energy dissipation within the elastomer," significantly improving the damping efficiency for low-frequency micro-amplitude vibrations of 1-100 Hz.

[0049] To complement the variable-structure cavity and further improve broadband power dissipation, the filling particulate composite medium can be designed in a composite manner, such as... Figure 6 As shown, the particulate composite medium has a high-density core such as iron-based or tungsten-based materials and a low-density shell such as silicone or polymer. This design enables the particulate composite medium to exhibit differentiated motion responses under different acceleration thresholds, increasing the complexity of collisions and energy transfer paths, and broadening the effective frequency band.

[0050] like Figure 7 As shown, when the above particles are dispersed in a non-Newtonian fluid such as a shear thickening fluid, the fluid will become instantaneously thickened or even "solidified" due to the high shear rate when the particle composite medium moves violently due to low-frequency large-amplitude vibration, providing additional impact buffering and energy dissipation; when the vibration is high-frequency and small-amplitude, the fluid remains liquid, allowing the particles to dissipate energy through friction.

[0051] As one embodiment of this invention, the above structure can be applied to the roof structure of a high-speed train. Multiple fins are embedded side by side into the aluminum structure cavity of the high-speed train roof. The unit is filled with a composite medium of density gradient particles and shear thickening liquid. The arrangement direction of the fin group is parallel to the length direction of the car body to mainly respond to vertical and longitudinal vibrations.

[0052] Stable operation at normal speed: The vehicle body vibrates smoothly, and the fins remain half-open (e.g., 15°-30°) under the preload of the spring sheet. The particulate medium mainly consumes energy through restricted flow and friction, effectively suppressing the mid-to-high frequency noise radiated by the vehicle body structure.

[0053] When passing through tunnels or intersecting at high speeds: strong aerodynamic loads cause large-amplitude, low-frequency vibrations in the vehicle body. The vibration energy directly drives the fins to move to a larger opening angle (such as 45°-60°), the cavity volume dynamically expands, the particulate composite medium enters a state of violent collision, the main energy dissipation mechanism switches instantaneously, and the powerful low-frequency vibration energy is dissipated in a targeted manner to suppress the vehicle body's roaring sound.

[0054] Compared to traditional fixed cavity structures filled with equal amounts of particles, this adaptive structure, through a structural modification mechanism, can improve vibration attenuation efficiency in key frequency bands (such as 100-1000Hz) by more than 50% without increasing weight, and the overall broadband average sound insulation is expected to increase by 5-15 dB.

[0055] This invention encompasses any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of this invention. To provide the public with a thorough understanding of this invention, specific details are described in detail in the following preferred embodiments; however, those skilled in the art will fully understand the invention even without these details. Furthermore, to avoid unnecessary misunderstanding of the essence of this invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0056] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An adaptive particle damping device, characterized in that, The device includes a damper housing, on which multiple variable-structure damping units are installed. One end of each variable-structure damping unit is rotatably connected to the inner sidewall of the damper housing, and the other end of each variable-structure damping unit is oscillating. The damper housing is filled with a particulate composite medium.

2. The adaptive particle damping device according to claim 1, characterized in that, The variable structure damping unit includes a variable structure damping shell and an elastic reset member. One end of the variable structure damping shell is rotatably connected to the inner wall of the damper housing. The bottom of the variable structure damping shell is connected to one end of the elastic reset member, and the other end of the elastic reset member is connected to the bottom inner wall of the damper housing.

3. The adaptive particle damping device according to claim 2, characterized in that, The modified damping unit is provided with an end rigid body section.

4. The adaptive particle damping device according to claim 3, characterized in that, The outer wall of the end rigid body section is fixedly connected to the middle elastic body section.

5. The adaptive particle damping device according to claim 4, characterized in that, The outer wall of the middle elastic body segment is fixedly connected to the root rigid body segment, and the bottom of the root rigid body segment is fixedly connected to the top of the elastic reset member.

6. The adaptive particle damping device according to claim 2, characterized in that, The variable-structure damping housing is provided with a rotating shaft, which is hinged to the side wall of the damper housing.

7. The adaptive particle damping device according to claim 6, characterized in that, The modified damping units are arranged in an array along the length of the damper housing.

8. The adaptive particle damping device according to claim 4, characterized in that, The central elastomer section is made of flexible memory sheet material, and slots are provided on both sides.

9. The adaptive particle damping device according to claim 5, characterized in that, The root rigid body segment is made of metal.

10. The adaptive particle damping device according to claim 2, characterized in that, The elastic reset member is made of metal, and a weakening part is provided at the middle position with symmetrically distributed upper and lower parts, and the structure of the weakening part protrudes outward.

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