Accession Number : AD0756570

Title :   Statistical Study of Sound Speed in the Inhomogeneous Upper Ocean.

Descriptive Note : Master's thesis,

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CALIF

Personal Author(s) : Fitzgerald,James Richard

Report Date : DEC 1972

Pagination or Media Count : 129

Abstract : The statistics of the fluctuations of the in-situ speed of sound in the upper ocean have been studied by analyzing the instantaneous phase difference of the output of two hydrophones separated by one meter for sounds of frequency 15 to 151 kHz. The experiment was conducted at 11 ft in water of depth 60 ft in low sea states at night. Comparison of the speed calculated from the time averaged phase difference, with the speed given by velocimeter or empirical relations, yielded differential speeds which deviate by 1 m/sec to 8 m/sec from the accepted values, for frequencies less than 100 kHz. Correlation and spectral analysis of the sound phase and ocean height fluctuations has shown the close relation between these two parameters. There is strong evidence of the presence and importance of bubbles in all of the results, particularly of a large population resonant in the frequency range 56.3 to 71.1 kHz (radius 50 to 60 microns) (Author Modified Abstract)

Descriptors :   (*UNDERWATER SOUND, VELOCITY), OCEAN WAVES, HYDROPHONES, PHASE SHIFT CIRCUITS, SPECTRUM ANALYZERS, TRANSDUCERS, BUBBLES, GRAPHICS, CURVE FITTING, COMPUTER PROGRAMS, POWER SPECTRA, THESES, STATISTICAL ANALYSIS

Subject Categories : Physical and Dynamic Oceanography
      Acoustic Detection and Detectors
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE