Bravo and C. Maury
50th International Congress and Exposition on Noise Control Engineering, INTERNOISE 2021
E-congress celebrado del 1 al 5 de agosto de 2021.
The problem of space-constrained absorbers in the low frequency range constitutes an area of continuous research. Micro-perforated panels are advantageous because they can be tuned by the selection of their constitutive physical parameters including the diameter of the perforations and their separation distance, the thickness and the length of the backing cavity. However, optimal selection is not straightforward, especially when considering multi-layer partitions. Current optimization algorithms perform on the maximization of the absorption coefficient defined over a frequency band, that presents a compromise between the bandwidth and the control device thickness. In this work, we analyze the problem on the basic of a causality criterion. This principle is generalized from its formulation in the field of electromagnetism to obtain a relation that correlates the thickness- to-bandwidth ratio of the micro-perforated absorber to the total absorption coefficient. Using this relation, an optimization procedure is presented for the sequential selection of the optimal physical parameters for a single-layer partition. An excellent agreement has been found between the optimal values obtained by the causality criterion and those achieved by other classical methods.
ACKNOWLEDGEMENTS This study was funded in Spain by the Ministerio de Economía y Competitividad project TRA2017- 87978-R, AEI/FEDER, UE, and the mobility program ILINK+2018. It was supported in France by the ANR VIRTECH (ANR-17-CE10-0012-01).
