Accession Number : AD0667739

Title :   AN INVESTIGATION OF THE STRUCTURE OF TURBULENCE OVER WATER SURFACE WAVES.

Descriptive Note : Progress rept.,

Corporate Author : MICHIGAN UNIV ANN ARBOR DEPT OF MATHEMATICS

Personal Author(s) : Portman,Donald J. ; Davidson,Kenneth L.

Report Date : MAR 1968

Pagination or Media Count : 41

Abstract : A hot-wire anemometer system, a fast response resistance wire thermometer and a thermocouple circuit were used in an attempt to measure the structure of turbulence, the turbulent fluxes of heat and momentum and the mean vertical temperature difference over ocean waves. To study data reliability (1) the recorded information was converted to voltage analogs and recorded on a paper chart and (2) spectral analyses were made for all channels of information for a representative six minute interval. It was found that a high noise level was present in all recordings and that it could be accounted for by voltage and frequency fluctuations in the power supplied for the magnetic tape recorder. The noise level masked the temperature measurement outputs which, apparently, were very small because of the nearly neutral thermal stratification during the experiments. On the basis of the preliminary analyses it appears that meaningful velocity spectra and cross spectra for frequencies less than 1.5 Hz may be computed from the recordings; higher frequency information is probably obscured by the high noise level. (Author)

Descriptors :   (*MARINE METEOROLOGY, *ATMOSPHERIC MOTION), TURBULENCE, OCEAN WAVES, WATER WAVES, SURFACE PROPERTIES, WIND, ANEMOMETERS, INTERFACES, RECORDING SYSTEMS, TRANSPORT PROPERTIES, THERMOMETERS, THERMOCOUPLES, POWER SPECTRA, DETECTORS, TEST METHODS

Subject Categories : Meteorology
      Physical and Dynamic Oceanography

Distribution Statement : APPROVED FOR PUBLIC RELEASE