28 / 2021-03-23 10:18:51

A Two-dimensional Asymmetric Eccentric Vibration Absorber with Acoustic Black Hole Features

Acoustic black hole,Asymmetric structure,Vibration control,Dynamic vibration absorber,Coupling analysis

Special Sessions > Acoustic black hole and vibro-acoustic coupling

In order to avoid the damage to the strength and stiffness of the controlled object caused by the traditional acoustic black hole (ABH) structure, an add-on two-dimensional circular ABH based dynamic vibration absorber (2D ABH-DVA) was used in the previous work. However, the previous ABH-DVA was a symmetrical structure, which led to the less coupling modes between the add-on ABH structure and the primary structure. Its broadband vibration reduction effect is not as good as expected. In this paper, an add-on two-dimensional asymmetric eccentric dynamic vibration absorber with acoustic black hole features (2D EABH-DVA) is proposed, which breaks the symmetry of the original structure. Using a plate as benchmark structure, both experimental and simulation results show an appreciable systematic reduction of its resonant peaks over a broad frequency range upon the deployment of the EABH-DVA structure without special parameter design. The coupling model of the primary structure and the add-on EABH-DVA is established. Compared with the symmetric model and the uniform model, it is proved that the eccentric structure has better vibration suppression effect. Similarly, the EABH-DVA has two main vibration suppression mechanisms: damping enhancement and dynamic interaction. Moreover, due to its abundant coupled modes, the damping ratio of the primary structure can be greatly increased, giving full play to the ABH effect.