Eventos Anais de eventos
DINAME 2023
XIX International Symposium on Dynamic Problems of Mechanics
Characterizing vibration attenuation in Herschel-Quincke beams by transmitted vibration and transmission loss
Submission Author:
Gabriel Angelini , SP
Co-Authors:
Gabriel Angelini, José Arruda
Presenter: Gabriel Angelini
doi://10.26678/ABCM.DINAME2023.DIN2023-0113
Abstract
This paper aims to use the well-known Herschel-Quincke (H-Q) acoustic tube principle to design beams that exhibit cancellation of flexural waves at certain frequencies. Unlike H-Q acoustic tubes, where the tube shape does not change the behavior of acoustic waves under the plane-wave assumption, a curved beam couples bending and longitudinal behavior, which makes the problem more complex. We investigate curved shapes used to fit a longer beam between two points, and their effect on the predicted cancellation frequencies. We first simulate an ideal problem, where two straight beams of different lengths are fitted (unrealistically) between two end beams, where cancellation occurs when the difference in the lengths of the two beams is equal to an odd integer number of half wavelengths, so that bending waves reach the receiver beam with opposite phase. Then, a realistic case, where the longer beam is curved, is addressed, and the differences with respect to the ideal case are discussed. The wave attenuation is also characterized using the transmission loss (TL) of the bending waves propagating along the beams. Finally, the H-Q beam TL is compared with the TL of a beam with periodically attached resonators.
Keywords
Vibration, Herschel-Quincke, Metamaterials, Transmission Loss
