Accession Number : ADA186905

Title :   Acoustic Backscattering from Bottom Sediment at Normal Incidence in the Laboratory.

Descriptive Note : Master's thesis,

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s) : Yu, Ta-Te

PDF Url : ADA186905

Report Date : Sep 1987

Pagination or Media Count : 100

Abstract : Normally incident sound pulses were used to investigate sediment types in the laboratory. Materials of five different grain sizes, ranging in diameter from 0.16 to 5.30mm, were used to find acoustic volume reverberation at three frequencies. An acoustic volume reverberation model was used to test the experimental data and to determine the scattering coefficients for the individual sediments. It was found that different sediments have different volume reverberations. From the slope of the trailing edge of the volume reverberation, the sediment type can be determined roughly. Different frequencies were used to find the relationship between volume reverberation and frequency, and the results showed that with increase in frequency the volume reverberation of the sediment will be decreased. Keyword: Acoustic waveform envelope; Acoustic scattering coefficient; Decay constant.

Descriptors :   *ACOUSTIC SCATTERING, *SEDIMENTS, ACOUSTIC EQUIPMENT, ACOUSTIC WAVES, ACOUSTICS, BACKSCATTERING, BOTTOM, COEFFICIENTS, DECAY, ENVELOPE(SPACE), EXPERIMENTAL DATA, GRAIN SIZE, MODELS, PULSES, REVERBERATION, SCATTERING, SOUND, VOLUME, OCEAN BOTTOM SOILS, THESES

Subject Categories : Acoustics
      Physical and Dynamic Oceanography

Distribution Statement : APPROVED FOR PUBLIC RELEASE