Study Of Active Noiseabsorption And Sensitivity Analysis Of Piezoelectric Composite Structure

Active noise absorption is an effective way to solve the low frequency noise, and thewide band noise reduction can be achieved by using a combination of active and passiveabsorption. As one kind of smart materials which can convert the energy between forceand electric, piezoelectric ceramic is widely researched and applied in the field of noiseand vibration control. Based on the popular finite element method, thepiezoelectric-rubber2-2mode composite structure is studied in this paper. The dynamiccharacteristics, the absorption performance and the sensitivity factors of the compositestructure are also analyzed in this paper which is conducted by the large commercial finiteelement software.Acoustic propagation, which is in the piezoelectric materials and in the uniformmulti-layer materials, as well as the active absorption theories of piezoelectric composite,is studied in this paper. The multi-physics finite element numerical formulation ofpiezoelectric material, which is in the structure-Piezoelectric-fluid couplingenvironment, is also derived accordingly. Two methods, the acoustic separation methodand the impedance matching method, are summarized and presented in this paper, which issuitable for calculating the material absorption coefficient by using the finite elementsoftware.Including the modal analysis, the harmonic analysis and the transient analysis, thedynamic characteristics of the rubber-steel layer, the PZT-steel layer and the piezoelectriccomposite are analyzed in this paper. Relationships between the surface pressure, thevoltage, the displacement and the velocity response are studied. As the harmonic pressureat different frequencies being applied to the surface of the structure, which simulates theplane sound waves impact, the surface acoustic impedance, the matching degree and thepassive absorption coefficient of the three materials underwater are calculated byextracting the surface velocity response.On the basis of the analysis of the dynamic characteristics and the absorptioncharacteristics of the above-mentioned three materials, sensitivity analysis of piezoelectriccomposite is applied. The sensitivity analysis could provide an effective reference for the active acoustic absorption by matching impedance while adjusting the structureparameters and the control voltage. Afterwards, the simulation analysis of the activeabsorption method of the piezoelectric composite structure is studied which is under acondition that a varying pressure and control voltage is loaded, in the end the resultactually shows that the low-frequency absorption characteristic is improved effectively.