Piezoelectric phononic crystal plate for actively controlling wave propagation path and application thereof

Abstract

The invention discloses a piezoelectric phononic crystal plate for actively controlling a wave propagation path and an application thereof. A piezoelectric material is used to cause a scatterer in a phononic crystal to show a negative equivalent elastic modulus, and therefore, a situation similar to a line defect appears. By changing the position of a piezoelectric piece to change the propagationdirection of a wave, the piezoelectric phononic crystal plate is more flexible than an original conventional line defect phononic crystal plate, the direction of the propagation of the wave can be randomly controlled or the propagation path of the wave is changed by adjusting the position of the piezoelectric piece without changing the structure of a phononic crystal material.

Description

technical field [0001] The invention belongs to an acoustic device similar to a waveguide original that can control the wave propagation path, specifically a piezoelectric phonon crystal plate that actively controls the wave propagation path, which can be used in various waveguide elements or other acoustic components. Devices can be used to change the propagation direction of waves, which can be used to prepare new types of signal separation devices. Background technique [0002] Traditional defect state phononic crystals are divided into point defects and line defects. Line defect state phononic crystals have a significant impact on the propagation path of control waves. Studies have shown that elastic waves can propagate in the path of line defects, thereby realizing the characteristics of waveguides. In practical applications, line-defect state phononic crystals can be used not only as various waveguide elements but also as other signal separation elements to change the ...

AI Technical Summary

Problems solved by technology

[0002] Traditional defect state phononic crystals are divided into point defects and line defects. Line defect state phononic crystals have a significant impact on the propagation path of control waves. Studies have shown that elastic waves can propagate in the path of line defects, thereby realizing the characteristics of waveguides. In practical applications, line-defect state phononic crystals can be used not only as various waveguide elements but also as other signal separation elements to change the direction of wave propagation, and are widely used, such as figure 1 Simplified diagram and physical diagram of two-dimensional three-component phononic crystal line defect. It can be seen from the modal diagram that by constructing a line defect in a phononic crystal, the sound wave propagates roughly along the line defect, and the sound pressure at other positions The response factor is relatively low. The advantage of this control sound wave propagation path is that it is easy to operate, simple in structure, and stable in effect. It has high application value as a waveguide element or signal separation element. However, the traditional line-defect phonon crystal structure is fixed, The direction of wave propagation cannot be changed, and the active control of wave propagation cannot be realized, which is not very flexible in practical applications

[0003] Deng Lianzhitong removed a row of carbon tetrachloride columns in the carbon tetrachloride / mercury system and replaced them with glycerol to form a two-dimensional three-component line defect state phononic crystal, such as figure 2 shown, and by changing the structure to study the influence of geometric parameters on the bandgap of phononic crystals, which is of great help to the design of frequency filters and acoustic transducers in engineering applications. This design realizes the It has strong practical value for wave propagation control characteristics, but it also has disadvantages such as fixed sound wave propagation position, single defect state, and too much dependence on structural design.

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