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Apparatus for measurements of time and space correlation

Description: The report describes a brief review is made of improvements to an experimental apparatus for time and space correlation designed for study of turbulence. Included is a description of the control of the measurements and a few particular applications.
Date: April 1955
Creator: Favre, Alexandre; Gaviglio, J & Dumas, R
Partner: UNT Libraries Government Documents Department

The Mass Transfer of Single, Solid Uranium Spheres to Flowing Molten Cadmium in Laminar and Turbulent Flow

Description: From Summary and Abstract: "In this study, a 1/2-inch diameter uranium sphere was used and molten cadmium was pumped past the test spheres at different flow rates. Mass transfer coefficients were determined from weight losses of the test spheres."
Date: September 1965
Creator: Traylor, E. Dean
Partner: UNT Libraries Government Documents Department

Measurements of intensity and scale of wind-tunnel turbulence and their relation to the critical Reynolds number of spheres

Description: The investigation of wind-tunnel turbulence, conducted at the National Bureau of Standards with the cooperation of the National Advisory Committee for Aeronautics, has been extended to include a new variable, namely, the scale of the turbulence. This report presents the results of a study of this new variable together with the intensity of the turbulence, and the effect of both on the critical Reynolds number of spheres.
Date: 1937
Creator: Dryden, Hugh L.; Schubauer, G. B.; Mock, W. C., Jr. & Skramstad, H. K.
Partner: UNT Libraries Government Documents Department

Preliminary Investigation in the NACA Low-Turbulence Tunnel of Low-Drag Airfoil Sections Suitable for Admitting Air at the Leading Edge

Description: From Summary: "An investigation was carried out in the NACA low-turbulence tunnel to develop low-drag airfoil sections suitable for admitting air at the leading edge. A thickness distribution having the desired type of pressure distribution was found from tests of a flexible model. Other airfoil shapes were derived from this original shape by varying the thickness, the camper, the leading-edge radius, and the size of the leading-edge opening. Data are presented giving the characteristics of the airfoil shapes in the range of lift coefficients for high-speed and cruising flight."
Date: July 1942
Creator: von Doenhoff, Albert E. & Horton, Elmer A.
Partner: UNT Libraries Government Documents Department

Correlation of data on the statistical theory of turbulence

Description: The statistical theory of turbulence affords an excellent medium for representing the kinematic conditions in turbulent flow and also serves as a valuable aid to exact experimental research. But it is still not developed enough for solving dynamic processes. Even in the simplest case of isotropic turbulence the calculation of the correlation curve or of the decrement of turbulence invariably reaches a point where clear-cut assumptions, such as omission of the inertia terms, or, earlier, mixing length assumptions or even merely general dimensional considerations, must be made.
Date: March 1942
Creator: Wieghardt, K.
Partner: UNT Libraries Government Documents Department

Some Basic Laws of Isotropic Turbulent Flow

Description: An Investigation is made of the diffusion of artificially produced turbulence behind screens or other turbulence producers. The method is based on the author's concept of disturbance moment as a certain theoretically well-founded measure of turbulent disturbances.
Date: September 1945
Creator: Loitsianskii, L. G.
Partner: UNT Libraries Government Documents Department

Some calculations of the lateral response of two airplanes to atmospheric turbulence with relation to the lateral snaking problem

Description: Report presenting calculations of the lateral response to representative time histories of atmospheric turbulence for two airplanes with widely different dynamic properties and explanations for their differences in behavior. The results indicate that atmospheric turbulence can cause and maintain a lateral hunting oscillation of a plane, which can be fairly regular and more pronounced for lightly damped airplanes. This may explain some of the cases of airplane snaking that have not been explained by other causes.
Date: May 1955
Creator: Bird, John D.
Partner: UNT Libraries Government Documents Department

Effect of spanwise variations in gust intensity on the lift due to atmospheric turbulence

Description: The effect of spanwise variations in gust intensity on the power spectrum directly due to atmospheric turbulence is calculated for several analytic approximations to the correlation function or power spectra of atmospheric turbulence, for several spanwise weighing functions (span loadings), and for various angles of sweepback.
Date: April 1957
Creator: Diederich, Franklin W. & Drischler, Joseph A.
Partner: UNT Libraries Government Documents Department

Spark ignition of flowing gases III : effect of turbulence promoter on energy required to ignite a propane-air mixture

Description: Report presenting an investigation to determine the effect of turbulence generated by different sizes of wire grid on the minimum spark-ignition energy of a flowing propane-air mixture. Gas-stream velocity, size of turbulence promoter, and distance from the promoter plate to the electrodes on minimum ignition energy were evaluated and the effects are shown in figures.
Date: January 14, 1953
Creator: Swett, Clyde C., Jr. & Donlon, Richard H.
Partner: UNT Libraries Government Documents Department

A reevaluation of gust-load statistics for applications in spectral calculations

Description: A review of the available information on the spectrum of atmospheric turbulence. A method based on these results is developed for the conversion of available gust statistics given in terms of counts of gust peaks into a form appropriate for use in spectral calculations. Some results that vary with types of operations are also provided.
Date: August 1955
Creator: Press, Harry & Meadows, May T.
Partner: UNT Libraries Government Documents Department

Spectrum of turbulence in a contracting stream

Description: The spectrum concept is employed to study the selective effect of a stream contraction on the longitudinal and lateral turbulent velocity fluctuations of the stream. By a consideration of the effect of the stream contraction on a single plane sinusoidal disturbance wave, mathematically not dissimilar to a triply periodic disturbance treated by G. I. Taylor, the effect on the spectrum tensor of the turbulence and hence on the correlation tensor is determined.
Date: August 30, 1951
Creator: Ribner, H. S. & Tucker, M.
Partner: UNT Libraries Government Documents Department

Theoretical calculation of the power spectra of the rolling and yawing moments on a wing in random turbulence

Description: Report presenting calculations of the correlation functions and power spectra of the rolling and yawing moments on an airplane wing due to the three components of continuous random turbulence. Specific numerical calculations are made for a pair of correlation functions given by simple analytic expressions which fit available experimental data.
Date: December 1956
Creator: Eggleston, John M. & Diederich, Franklin W.
Partner: UNT Libraries Government Documents Department

Theoretical calculation of the power spectra of the rolling and yawing moments on a wing in random turbulence

Description: The correlation functions and power spectra of the rolling and yawing moments on an airplane wing due to the three components of continuous random turbulence are calculated. The rolling moments to the longitudinal (horizontal) and normal (vertical) components depend on the spanwise distributions of instantaneous gust intensity, which are taken into account by using the inherent properties of symmetry of isotropic turbulence. The results consist of expressions for correlation functions or spectra of the rolling moment in terms of the point correlation functions of the two components of turbulence.
Date: September 6, 1956
Creator: Eggleston, John M. & Diederich, Franklin W.
Partner: UNT Libraries Government Documents Department

Turbulent flow

Description: Report presenting some information and potential areas of study of turbulent flow and turbulence.
Date: October 1927
Creator: Prandtl, L.
Partner: UNT Libraries Government Documents Department

Scale-effect tests in a turbulent tunnel of the NACA 65(sub 3)-418, a = 1.0 airfoil section with 0.20-airfoil-chord split flap

Description: Report presenting the effect of Reynolds number on the aerodynamic characteristics of a low-drag airfoil section tested under conditions of relatively high stream turbulence. The data are presented as curves of section angle of attack, section profile-drag coefficient, and section pitching-moment coefficient against section lift coefficient for various flap deflections.
Date: September 1944
Creator: Tucker, Warren A. & Wallace, Arthur R.
Partner: UNT Libraries Government Documents Department

Airspeed fluctuations as a measure of atmospheric turbulence

Description: From Introduction: "Increments in structural loads due to atmospheric turbulence can be accurately expressed in terms of flight speed and effective gust velocities (reference 4). Data from which the effective gust velocities could be computed were also obtained during the flights of the XC-35 airplane. These data have been used to determine the significance of the fluctuations in the pilot's indicated-airspeed readings in relation to structural loads to due to atmospheric turbulence."
Date: July 1945
Creator: Tolefson, H B
Partner: UNT Libraries Government Documents Department

An analysis of the indications of the University of Chicago airborne turbulence indicator in gusty air

Description: From Introduction: "The present report has been prepared to discuss the indications obtained from the University of Chicago turbulence indicator in relation to simultaneous measurement of atmospheric gustiness made by the NACA, which are summarized herein."
Date: August 1946
Creator: Pratt, K G
Partner: UNT Libraries Government Documents Department

Effect of stabilizing forces on turbulence

Description: The appearance of expressed discontinuity layers in the free atmosphere, where a warm air mass flows over a cold mass without perceptible intermingling forms the basis of the present report. In these experiments an air stream is to be blown between a water-cooled and a vapor-heated plate. According to what preceded it is anticipated that the exchange will be enhanced. Because these experiments had to be made at relatively low air speeds so as to let the lifting forces become effective, it first required a study of the test methods, and so we have not yet proceeded beyond the preliminary tests on the most suitable hot-wire connections and thermocouples for recording speed and temperature.
Date: June 1931
Creator: Prandtl, L.
Partner: UNT Libraries Government Documents Department

The variation of atmospheric turbulence with altitude and its effect on airplane gust loads

Description: Report presenting information on the amount and relative intensity of atmospheric turbulence for altitudes up to 60,000 as obtained by airplanes and balloon-borne instruments. Analysis of the data obtained indicated that there are substantial reductions in turbulence at higher altitudes in the weather conditions measured in the tests. Results regarding gust distributions, including non-thunderstorm turbulence, thunderstorm turbulence, total gust distributions, and a comparison of gusts are also provided.
Date: November 9, 1953
Creator: McDougal, Robert L.; Coleman, Thomas L. & Smith, Philip L.
Partner: UNT Libraries Government Documents Department

The use of wind tunnels to predict flight buffet loads

Description: From Summary: "Methods and techniques developed for the study of buffeting by use of wind-tunnel models are described. Requirements on model damping and frequency characteristics, the model support system, and the effects of wind-tunnel turbulence on buffet tests are outlined. The results are shown of a recent comparison of buffet loads measured on a research airplane with thin unswept wings and on two different models of the airplane in two different wind tunnels."
Date: June 10, 1957
Creator: Davis, Don D., Jr. & Huston, Wilber B.
Partner: UNT Libraries Government Documents Department