Date of Award
Doctor of Philosophy in Electrical Engineering
Instrumentation, a stable oceanographic platform, and a data acquisition system were constructed and utilized to record wind driven ocean waves. Wave data were processed, and the results which are presented are used in a comparative study of wave recording techniques.
A system of capacitive wave staffs which indicates direct surface displacement, a dynamic pressure sensor which indicates wave height by sensing the hydrostatic pressure slightly below the ocean surface, and a microthermal probe which indicates small scale and rapid temperature fluctuations were developed. Also used in the study was a ducted impeller current meter which indicates water particle velocity. Thus the wave staffs indicate the phenomenon under study directly; the other three devices indicate related phenomena.
It was desired to record deep water waves in the open ocean. While several stable platforms suitable for recording waves by the aforementioned instrumentation are obtainable they were either unavailable at the time the work was performed or are not suited for use in the locale chosen for the work. Consequently, a stable spar buoy was designed, constructed, and its performance evaluated. It is shown to be useful for experiments of this nature.
A data acquisition system, consisting of an analog FM tape recorder, an incremental (digital) tape recorder, and several pieces of peripheral equipment, was assembled. Extensive evaluation shows this system to be a very satisfactory means of handling time series data.
Instrument deficiencies, notwithstanding, the various power spectra, autocorrelations, cross-correlations, and statistics calculated from the data from the four instruments show there is a high degree of coherence. As should be expected the least coherence is shown between the output records from the microthermal probe and those from the other three devices.
Barrett, Alfred Henry, "The Measurement of Wind Generated Waves in the Deep Ocean" (1970). Open Access Dissertations. Paper 1584.