| Popis: |
This paper investigates the acoustic behavior of free flooding resonators consisting of inverted cups that are lowered into a water column such that a volume of air is entrapped within the cavity upon submersion. Similar to a two-fluid Helmholtz resonator, the resonance frequency is determined by the compliance of the entrapped air and the radiation mass of water at the opening of the cavity. The entrapped air mass is compressed as the resonator is lowered to depth due to the increase in hydrostatic pressure, which affects the acoustic behavior. Collections of similar resonators with compliant walls were previously investigated for use in underwater noise abatement [Lee et al., Proc. Meeting Acoustics 22, 045004 (2015)]; however, recent work has shown an increase in quality factor and attenuation performance for stiffer walled resonators. Measurements were taken to determine the resonance frequencies and quality factors of both individual resonators and arrays of resonators comprised of various wall mater... |
