Lift Hysteresis at Stall as an Unsteady Boundary-Layer Phenomenon (open access)

Lift Hysteresis at Stall as an Unsteady Boundary-Layer Phenomenon

"Analysis of rotating stall of compressor blade rows requires specification of a dynamic lift curve for the airfoil section at or near stall, presumably including the effect of lift hysteresis. Consideration of the Magnus lift of a rotating cylinder suggests performing an unsteady boundary-layer calculation to find the movement of the separation points of an airfoil fixed in a stream of variable incidence. The consideration of the shedding of vorticity into the wake should yield an estimate of lift increment proportional to time rate of change of angle of attack" (p. 881).
Date: August 17, 1955
Creator: Moore, Franklin K.
System: The UNT Digital Library
Spectra and diffusion in a round turbulent jet (open access)

Spectra and diffusion in a round turbulent jet

"In a round turbulent jet at room temperature, measurement of the shear correlation coefficient as a function of frequency (through band-pass filters) has given a rather direct verification of Kolmogoroff's local-isotropy hypothesis. One-dimensional power spectra of velocity and temperature fluctuations, measured in unheated and heated jets, respectively, have been contrasted. Under the same conditions, the two corresponding transverse correlation functions have been measured and compared" (p. 1).
Date: August 17, 1949
Creator: Corrsin, Stanley & Uberoi, Mahinder S.
System: The UNT Digital Library
Formation and Combustion of Smoke in Laminar Flames (open access)

Formation and Combustion of Smoke in Laminar Flames

"The nature and formation of smoke and its combustion were investigated. Smoke, which consist of tiny mesomorphous crystals tightly packed into popcorn-ball-like particles that agglomerate to give filaments, was found to contain about 5 percent of the hydrogen originally present in the fuel. Factors affecting smoke formation were studied in both diffusion flames and premixed Bunsen flames. It is suggested that smoking tendency increases with increasing stability of the carbon skeleton of the molecule, as determined by relative bond strength" (p. 657).
Date: August 17, 1954
Creator: Schalla, Rose L.; Clark, Thomas P. & McDonald, Glen E.
System: The UNT Digital Library
A Theory for Primary Failure of Straight Centrally Loaded Columns (open access)

A Theory for Primary Failure of Straight Centrally Loaded Columns

"A theory of primary failure of straight centrally loaded columns is presented. It is assumed that the column cross section and the load are constant throughout the length. Primary failure is defined as any type of failure in which the cross sections are translated, rotated, or translated and rotated but not distorted in their own planes" (p. 141).
Date: August 17, 1936
Creator: Lundquist, Eugene E. & Fligg, Claude M.
System: The UNT Digital Library
Relation of Hydrogen and Methane to Carbon Monoxide in Exhaust Gases From Internal-Combustion Engines (open access)

Relation of Hydrogen and Methane to Carbon Monoxide in Exhaust Gases From Internal-Combustion Engines

The relation of hydrogen and methane to carbon monoxide in the exhaust gases from internal-combustion engines operating on standard-grade aviation gasoline, fighting-grade aviation gasoline, hydrogenated safety fuel, laboratory diesel fuel, and auto diesel fuel was determined by analysis of the exhaust gases. Two liquid-cooled single-cylinder spark-ignition, one 9-cylinder radial air-cooled spark-ignition, and two liquid-cooled single-cylinder compression-ignition engines were used.
Date: August 17, 1933
Creator: Gerrish, Harold C. & Tessmann, Arthur M.
System: The UNT Digital Library
Relative Worth of Improvements of Fabrics (open access)

Relative Worth of Improvements of Fabrics

Report presents an equation that connects all the major qualities of a fabric, from which the fabric may be rigidly designed with respect to maximum ultimate economy.
Date: August 17, 1915
Creator: Goodyear Tire And Rubber Company
System: The UNT Digital Library