Periodic structures based on coupled Helmholtz resonators for broadband noise suppression (en)
* Presenting author
Abstract:
In this work we study periodic arrays of strongly coupled Helmholtz resonators in order to design a structure allowing broadband noise insulation. The aim is to develop a sparse structure to achieve ventilation and partial optical transparency while preserving a simple design. The investigations start from an infinite periodic structure and tuning of its parameters to maximize band-gaps. After that the equivalent semi-infinite and finite structures are studied numerically and experimentally. The measured spectrally averaged transmission coefficients within a range from 2000 to 16500 Hz are -31.6 dB and -18.6 dB, correspondingly. We also show a possibility to achieve a compromise between ventilation and noise insulation. In particular, the spectrally averaged transmission of a finite structure might be about -15 dB while only 25% of an air flow is blocked. In addition, we demonstrate that various structural defects can lead to the enhancement of noise insulating properties.