Attenuation of airborne noise by wet and dry neoprene diving hoods
نویسندگان
چکیده
The insertion losses of five neoprene diving hoods varying thicknesses (2 mm–9 mm) were measured in one-third octave bands using a Kemar manikin diffuse broadband noise field. air for both dry and wet hoods. loss was calculated as the sound level each frequency band with hood, minus corresponding without hood. similar ears manikin. Both neither attenuated nor amplified below 250 Hz. Between 315 Hz–1250 Hz, hood negative, displaying broad resonance gain 6–8 dB. In this range acts mass-spring system, resonating like drum skin when stretched over ears. Above 1000 increased (10 dB per octave), reaching maximum 5000 Hz–6000 Wetting did not significantly affect loss; 'drum-skin' marginally lower may be greater between Hz– 10 000 decreased increasing at frequencies above thickness.
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ژورنال
عنوان ژورنال: Underwater Technology
سال: 2021
ISSN: ['1756-0551', '1756-0543']
DOI: https://doi.org/10.3723/ut.38.003