Additional eccentric acoustic black hole vibration reduction structure

Abstract

The invention relates to an additional eccentric acoustic black hole vibration reduction structure, and in a uniform area, namely a cylindrical area, of the vibration reduction structure, the propagation speed and wavelength of waves with a certain frequency are not changed. However, at an acoustic black hole part, the propagation speed of the wave is reduced along with the reduction of the thickness; the wavelength is reduced, the vibration amplitude of waves is increased and is gathered toward an area with reduced thickness, when the waves arrive at the cut-off position, due to the fact thatthe vibration reduction structure is provided with an acoustic black hole extending part, namely a first annular part, bending waves continue to be propagated at the wavelet speed, the weak-structureposition occurs at the outermost end of the structure, the deformation of the outer end is easier, the acoustic black hole effect is easier to occur, and the high-efficiency broadband vibration reduction and noise reduction are achieved.

Description

technical field [0001] The invention relates to the technical field of vibration reduction and noise reduction, in particular to an additional eccentric acoustic black hole vibration reduction structure. Background technique [0002] Vibration is the standing wave generated by multiple reflections of the boundary in the structure, and noise is the wave energy radiated into the air by the structure vibration. Therefore, manipulating the wave behavior in the structure is an effective means to reduce the vibration and noise of the structure. Today's more common wave manipulation is mainly divided into two methods: active and passive. Active methods generally require external energy supply, and the design system is very cumbersome, so there is no large-scale promotion at present. In addition, for passive methods, the most basic form is additional damping materials, and some viscoelastic materials can effectively absorb vibration energy. However, for some major equipment, a lar...

AI Technical Summary

Problems solved by technology

[0004] However, the traditional acoustic black hole structure achieves the purpose of vibration reduction and noise reduction by tailoring the controlled object, which inevitably reduces the stiffness and strength of the structure. Such a design is not applicable in some key structural designs

Images