Serial/Series Title

Study by the Prandtl-Glauert method of compressibility effects and critical Mach number for ellipsoids of various aspect ratios and thickness ratios (open access)

Study by the Prandtl-Glauert method of compressibility effects and critical Mach number for ellipsoids of various aspect ratios and thickness ratios

From Summary: "By the use of a form of the Prandtl-Glauert method that is valid for three-dimensional flow problems, the value of the maximum incremental velocity for compressible flow about thin ellipsoids at zero angle of attack is calculated as a function of the Mach number for various aspect ratios and thickness ratios. The critical Mach numbers (within the accuracy of the Prandtl-Glauert method) of the various ellipsoids are also determined. The results indicate an increase in critical Mach number with decrease in aspect ratio which is large enough to explain experimental results on low-aspect-ratio wings at zero lift."
Date: January 1949
Creator: Hess, Robert V. & Gardner, Clifford S.
System: The UNT Digital Library
Propeller Flight Investigation to Determine the Effects of Blade Loading (open access)

Propeller Flight Investigation to Determine the Effects of Blade Loading

Note presenting a flight investigation of a three-blade propeller in climb and at high speed to determine the effects of blade power loading. Increasing the blade power coefficient from 0.06 to 0.09 was found to increase the efficiency approximately 8 percent at an airplane Mach number of 0.7 and a propeller-tip Mach number of 1.13. In climb, an increase in power loading over the range of blade power coefficients investigated was shown to reduce efficiency, as a consequence of increased induced drag losses.
Date: January 1950
Creator: Hammack, Jerome B. & Vogeley, A. W.
System: The UNT Digital Library
The Tracer Gas Method of Determining the Charging Efficiency of Two-Stroke-Cycle Diesel Engines (open access)

The Tracer Gas Method of Determining the Charging Efficiency of Two-Stroke-Cycle Diesel Engines

"A convenient method has been developed for determining the scavenging efficiency or the charging efficiency of two-stroke-cycle engines. The method consists of introducing a suitable tracer gas into the inlet air of the running engine and measuring chemically its concentration both in the inlet and exhaust gas. Monomethylamine CH(sub 3)NH(sub 2) was found suitable for the purpose as it burns almost completely during combustion, whereas the "short-circuited" portion does not burn at all and can be determined quantitatively in the exhaust" (p. 1).
Date: January 1942
Creator: Schweitzer, P. H. & DeLuca, Frank, Jr.
System: The UNT Digital Library
Application of the Laplace Transformation to the Solution of the Lateral and Longitudinal Stability Equations (open access)

Application of the Laplace Transformation to the Solution of the Lateral and Longitudinal Stability Equations

Note presenting the application of the Laplace transformation to the solution of the lateral and longitudinal stability equations. The expressions for the time history of the motion in response to a sinusoidal control motion are derived for the general case in which all initial measurements are assumed different from zero.
Date: January 1950
Creator: Mokrzycki, G. A.
System: The UNT Digital Library