INVESTIGATION OF ACOUSTIC CHARACTERISTICS AND DB REDUCTION OF MICROSPHERE-BASED PANELING ON DIVING WETSUITS

Scuba divers are exposed to potentially harmful temperatures and noise intensities while operating underwater. Standard neoprene wetsuits modified with glass-microsphere composite panels have been shown to improve the thermal capabilities of the suit and retain more of the diver’s body heat. While neoprene is an effective sound absorber itself, the acoustic properties and sound-proofing capabilities of the created composite panels were investigated. Several composite panels were used to shield a hydrophone receiver from a source signal over a range of frequencies from 10 Hz to 20 kHz and compared to a 7 mm neoprene sample. Results indicate a variable dB reduction in sound pressure over this range, with the measured intensity transmission coefficients of the composites being comparable to neoprene past a frequency of approximately 13 kHz. When used in tandem with neoprene, the material further reduces the measured pressure of the source signal. While not as effective as neoprene itself, the composite material shows potential for underwater soundproofing uses. Further experimentation with panel composition may yield a more effective sound absorbing material.
Ensign, United States Navy
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