Investigation with an interferometer of the turbulent mixing of a free supersonic jet (open access)

Investigation with an interferometer of the turbulent mixing of a free supersonic jet

The free turbulent mixing of a supersonic jet of Mach number 1.6 has been experimentally investigated. An interferometer, of which a description is given, was used for the investigation. Density and velocity distributions through the mixing zone have been obtained. It was found that there was similarity in distribution at the cross sections investigated and that, in the subsonic portion of the mixing zone, the velocity distribution fitted the theoretical distribution for incompressible flow. It was found that the rates of spread of the mixing zone both into the jet and into the ambient air were less than those of subsonic jets.
Date: January 21, 1949
Creator: Gooderum, Paul B.; Wood, George P. & Brevoort, Maurice J.
System: The UNT Digital Library
On Stability of Free Laminar Boundary Layer Between Parallel Streams (open access)

On Stability of Free Laminar Boundary Layer Between Parallel Streams

"An analysis and calculations on the stability of the free laminar boundary layer between parallel streams were made for an incompressible fluid using the Tollmien-Schlichting theory of small disturbances. Because the boundary conditions are at infinity, two solutions of the Orr-Sommerfeld stability equations need not be considered, and the remaining two solutions are exponential in character at the infinite boundaries. The calculations show that the flow is unstable except for very low Reynolds numbers" (p. 571).
Date: March 21, 1949
Creator: Lessen, Martin
System: The UNT Digital Library
Effects of wing flexibility and variable air lift upon wing bending moment during landing impacts of a small seaplane (open access)

Effects of wing flexibility and variable air lift upon wing bending moment during landing impacts of a small seaplane

From Summary: "A smooth-water-landing investigation was conducted with a small seaplane to obtain experimental wing-bending-moment time histories together with time histories of the various parameters necessary for the prediction of wing bending moments during hydrodynamic forcing functions. The experimental results were compared with calculated results which include inertia-load effects and the effects of air-load variation during impact. The responses of the fundamental mode were calculated with the use of the measured hydrodynamic forcing functions. From these responses, the wing bending moments due to the hydrodynamic load were calculated according to the procedure given in R.M. No. 2221. The comparison of the time histories of the experimental and calculated wing bending moments showed good agreement both in phase relationship of the oscillations and in numerical values."
Date: December 21, 1949
Creator: Merten, Kenneth F. & Beck, Edgar B.
System: The UNT Digital Library
Two-dimensional compressible flow in centrifugal compressors with straight blades (open access)

Two-dimensional compressible flow in centrifugal compressors with straight blades

"Six numerical examples are presented for steady, two-dimensional, compressible, nonviscous flow in centrifugal compressors with thin straight blades, the center lines of which generate the surface of a right circular cone when rotated about the axis of the compressor. A seventh example is presented for incompressible flow. The solutions were obtained in a region of the compressors, including the impeller tip, that was considered to be unaffected by the diffuser vanes or by the impeller-inlet configuration" (p. 141).
Date: June 21, 1949
Creator: Stanitz, John D. & Ellis, Gaylord O.
System: The UNT Digital Library