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Velocity and temperature fluctuation measurements were made over the open ocean from instruments mounted on the R/V ACANIA. These data were examined to determine the validity of present formulations and prediction techniques. Values of momentum flux, u* 2, were inferred from the rate of dissipation of turbulent kinetic energy, E. Dissipation values were obtained from spectral estimates and inner scale estimates. Values of u* were examined for representativeness on the basis of the constant-flux assumption and by comparisons with other studies. The vertical variation of the dissipation rate was examined for possible effects of stability and wind-wav e coupling. The momentum flux, computed from spectra, supported the constant-flux assumption for neutral conditions. For periods of instability, the stability corrections applied to the vertical variation of E resulted in the proper adjustments toward the predicted slope. The reductions in momentum transfer during periods of stable stratifications were consistent with wind-wave coupling effects described by Davidson. The shape of a spectrum of temperature fluctuations was in agreement with predictions.

Over 11,000, 1N971-3 diffused junction silicon zener diodes were screened and life tested. Failure analysis was performed on failed devices to determine existing failure mechanisms so that the most beneficial screen could be established. In addition, a cost model was developed to functionally relate screening to the reliability required by the user of the diodes. The results of these investigations, including the final form of a linear discriminate function developed to classify initial units as superior or inferior, are presented in this report. (Author)

An observational study was made during August, September and October 1968 to investigate the influence of water waves on the adjacent airflow. Simultaneous measurements of wind and temperature fluctuations and waves were made from a tower on Lake Michigan. 11 periods were analyzed, and 8 included simultaneous measurements of velocity and temperature fluctuations at two levels above the mean water level. Hot-wire anemometers with X-probe sensors were used to obtain both the along-wind and vertical components of the fluctuating wind. High response resistance wires were used to measure temperature fluctuations and a capacitance gauge was used to measure the waves. Data were analyzed to obtain variance and covariance spectra over a frequency range from .01 to 15 Hz and are presented over a range from .03 to 10 Hz. (Author)

Simultaneous measurements of wind velocity components with hot-film anemometers, air temperature fluctuations, and wave heights were made about 200 miles east northeast of Barbados during BOMEX. A total of 54 hours of measurements were made during the last two weeks in May, 1969. Of these, 23 had simultaneous recordings of wind velocity components and temperature fluctuations at two heights. Measurement heights were 2, 3, 6 and 8 meters above mean water level. Three different computer facilities have been employed in processing the data to obtain probability distribution functions, joint probability distribution functions, spectrum functions and cross-spectrum functions for velocity components, temperature fluctuations and wave heights. Examples of the calculation results are given and briefly described. They show specific effects of waves on the velocity components. (Author)

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)

The shapes of spectra obtained from measurements of ocean turbulence are examined. Kovasznay's equation for high wave number turbulence is used to describe the inertial through dissipation regions. Power spectra of velocity fluctuation recorded in the open sea are used to evaluate constants occurring in the Kovasznay relation. Semi-empirical forms of high wave number energy spectra are then displayed. These computed spectra should define a universal form to which mathematical models should adhere.

The "ramp" is an often observed feature in temperature fluctuations during unstable atmospheric conditions. It is characterized by a gradual increase in temperature followed by a sudden drop to an ambient level. This ramp clearly distinguishes temperature signals from other turbulence signals such as velocity. Three different ramp-type atmospheric temperature fluctuations and their derivatives are constructed and statistically examined for the parameters skewness and coefficient of excess., These statistical values are compared with values obtained from actual signals. The "complex ramp signal" was found to represent these quite well. Skewness and coefficient of excess for this signal could be altered almost independently of each other. The complex ramp is constructed by inscribing nearly symmetrical consecutive triangles within two envelope rays of constant but different slopes such that the two envelope rays approximate a ramp function.

Measurements of high frequency temperature and velocity fluctuations were made in the atmospheric boundary layer. These data were analyzed using analog correlating techniques to obtain the structure function rather than spectral methods to obtain the spectral densities. The autocorrelation function of temperature fluctuations at 4 meters and 2 meters was computed as was the autocorrelation function of downstream velocity fluctuations at 4 meters. The cross-correlation function of temperature and downstream velocity fluctuations at 4 meters was also examined. These results supported the Kolmogorov ideas at high wave numbers. There is apparently very little correlation between downstream velocity fluctuations and temperature fluctuations. This indicates the independence of the two sensing systems and that temperature fluctuations are related primarily to vertical air movement rather than random fluctuations in the horizontal air flow. This aspect is further clarified by examining the temperature fluctuation records at two heights.

Spectral analyses are performed on turbulence data obtained over natural ocean waves during BOMEX. Results are obtained for variance and co-variance spectra, phase and coherence relationships, and amplitude ratios. Peaks in the horizontal and vertical velocity spectra are observed to correspond to the frequency of the wave spectra peaks. Phase relationships tend to obey predictions of potential flow theory in regions of the wave spectra peaks. However, the wave related motion contributes to the momentum transfer which is not predicted by potential flow theory. The ratio of the wave induced disturbance to the sea surface displacement is used to locate the wave spectra frequency for which the level of measurement is a critical level. Results of the study are readily compared to existing wind-wave coupling theories, both linear and non-linear.

The relationship between vertical motion at the top of the boundary layer, geostrophic vorticity in the boundary layer and divergence in the boundary layer are examined in this study. The equation of motion and the continuity equation are applied to a homogeneous barotropic atmosphere using a numerical model in this study. The solutions reveal that the boundary layer is stable for very large values of Ro in the case of positive vorticity and becomes unstable at Ro = 1 .0 in the case of negative vorticity. A difference in behavior is found between cases of anticyclonic and cyclonic shear. The magnitude of the vertical velocity is greater and the boundary is thicker for anticyclonic than for cyclonic shear systems of equivalent strength.

Turbulence data obtained over natural water waves were analyzed using joint probability distribution and conditional means methods. These data represented conditions when the waves were decaying and when the waves were building. In both cases, significant wave-induced fluctuations were identified in the airflow. All features of the velocity fluctuations were examined for two levels above mean water level. In the case of a decaying wave field, decelerations in the airflow can be associated with an assumed propagating pressure maximum over the crest of the wave. Other than this deceleration, the airflow appears to reflect simple streamline bending over the mobile irregular wave surface. In the case of a building wave field, velocity fluctuations appear to agree with those predicted by linear wave generating theories.

Spectral and cospectral analyses are performed on turbulence data obtained over natural ocean waves during BOMEX. Results are obtained for normalized spectra and cospectra. Significant scatter is observed throughout the spectra and cospectra with a larger degree of scatter in the low frequency range. Kolmogorov's -5/3 power law is found to describe the longitudinal and vertical velocity spectra in the high frequency range. However, it is not applicable to the lateral velocity spectra while results for the temperature spectra are inconclusive. Monin-Obukhov similarity theory well describes the vertical velocity spectra yet its application to horizontal velocity spectra is doubtful. Similarity theory does not seem to adequately describe the uw cospectra. Results from comparing similairt theory to temperature spectra and wT cospectra indicate the presence of an influence not accounted for by similarity theory. When compared, uw and wT cospectra are found to be significantly different. All computed spectra and cospectra are found to have a relatively larger amount of energy in the low frequency range than their respective over land spectra and cospectra.

Simultaneous observations of wave heights and velocity fluctuations at two levels above the waves are analyzed to examine properties of the wave-related fluctuations in the airflow. Results are obtained from spectral and joint probability density function, conditional mean function (JPDF-CMF) analyses. Results are examined with respect to predictions from potential flow theory and recent theoretical formulations for wind-wave coupling. Of interest are recent formulations which allow interaction between the wave-induced motion and turbulence in the airflow, the so-called "turbulence" models.