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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Aero-astrodynamics - Newtonian aerodynamics, turbulent flux in hot and multicomponent flows, slender body theory, automatic data processing, and hot-wire turbulence measuring apparatus
Aeronautical turbulence measuring apparatus - gust loading
Clear air turbulence problems including forecasting inadequacy, detection device requirements, categories, etc
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A thorough understanding of the turbulent flow movements cannot be arrived at from investigations of the temporal mean values of the flows alone. Study of the fluctuation phenomena themselves is indispensable. Thus turbulence research entered a new promising stage when investigators started performing fluctuation measurements and basing theories on those measurements. The investigations of fluctuations carried out so far refer almost exclusively to the so-called isotropic turbulence. It represents a damping phenomenon; it is the simplest type of turbulence where merely the longitudinal fluctuations need to be measured. However, it is precisely nonisotropic turbulence which involves the most essential problem of the turbulent exchange movement and the turbulent apparent friction. Investigation of nonisotropic turbulence requires measurement of longitudinal and transverse fluctuations.
Construction of aircraft thermoanemometer for measuring atmospheric turbulence
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.
Power spectral density /PSD/ methods applied to prediction of aircraft responses to continuous turbulence
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Device to measure turbulent flows by cross correlation of optical signals
This is an account of an investigation in which oscillations were discovered in the laminar boundary layer along a flat plate. These oscillations were found during the course of an experiment in which transition from laminar to turbulent flow was being studied on the plate as the turbulence in the wind stream was being reduced to unusually low values by means of damping screens. The first part of the paper deals with experimental methods and apparatus, measurements of turbulence and sound, and studies of transition. A description is then given of the manner in which oscillations were discovered and how they were found to be related to transition, and then how controlled oscillations were produced and studied in detail.
Use of radiosondes to measure atmospheric turbulences
Summary of static and dynamic calibrations of hot-wire systems for use in low density flows with high turbulence levels
Universal turbulence measuring system giving quantitative measure of turbulent intensity independent of type or speed of aircraft, using all-weather sensor
Hot wire measurement of tangential velocity and Reynolds stresses in spiral laminar-turbulent flow
Local turbulent properties of shear layer derived from covariance of two crossed perpendicular beams of radiation
Power spectral density /PSD/ methods applied to prediction of aircraft responses to continuous turbulence
Longitudinal turbulence intensities, autocorrelations, energy spectra and peak energy dissipation frequencies for organic solvents flowing in smooth round tubes