Eventos Anais de eventos
DINAME 2017
XVII International Symposium on Dynamic Problems of Mechanics
FLEXURAL WAVE BAND GAPS IN A 1D PHONONIC CRYSTAL BEAM
Submission Author:
Edson Jansen Pedrosa de Miranda Junior , MA
Co-Authors:
Edson Jansen Pedrosa de Miranda Junior, Jose Maria Campos dos Santos
Presenter: Edson Jansen Pedrosa de Miranda Junior
doi://10.26678/ABCM.DINAME2017.DIN17-0046
Abstract
In this study, it is investigated theoretically and experimentally the forced response of elastic waves propagating in a 1D phononic crystal (PC) beam and its band structure. The PC beam unit cell is composed by steel and polyethylene. The study is performed by using six methods, the finite element (FE), spectral element (SE), wave finite element (WFE), wave spectral element (WSE), conventional plane wave expansion (CPWE) and improved plane wave expansion (IPWE). Simulated examples of 1D PC beam, considering unit cells of different sizes, with Bragg-type gaps, are calculated. The forced response results are presented in the form of displacement, transmittance and receptance, and the elastic band structure is investigated using its real and imaginary (attenuation) parts. The numerical results of all methods are in a good agreement, except by the limitation of WFE and FE methods in high frequencies. It is also studied the polyethylene quantity influence on the attenuation constant. Depending on the application, choosing the polyethylene quantity correctly is not simple, because it is related to the unit cell size and in which frequency the band gap start. An experiment of a 1D PC beam is proposed and the numerical results can localize the band gap position and width close to the experimental results. A small Bragg-type gap with low attenuation is observed between 405 Hz – 720 Hz. The 1D PC beam with unit cells of steel and polyethylene presents potential application for vibration control.
Keywords
1D phononic crystal beam, flexural vibration, band gaps, Vibration control
