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The Condensation Line of Air and the Heats of Vaporization of Oxygen and Nitrogen

Description: "The condensation pressure of air was determined over the range of temperature from 60 to 85 K. The experimental results were slightly higher than the calculated values based on the ideal solution law. Heat of vaporization of oxygen was determined at four temperatures ranging from about 68 to 91 K and of nitrogen similarly at four temperatures ranging from 62 to 78 K" (p. 1).
Date: June 1953
Creator: Furukawa, George T. & McCoskey, Robert E.
Partner: UNT Libraries Government Documents Department

Contribution to the Problem of Flow at High Speed

Description: Report divided into two sections about flow problems encountered at high speeds. The topics include: 1) A Few General Remarks Covering the Prandtl-Busemann Method; and 2) Effect of Compressibility in Axially Symmetrical Flow around an Ellipsoid.
Date: June 1949
Creator: Schmieden, C. & Kawalki, K. H.
Partner: UNT Libraries Government Documents Department

Profile Measurements During Cavitation

Description: One of the problems of modern cavitation research is the experimental determination of the wing loads on airfoils during cavitation. Such experiments were made on various airfoils with the support of the naval ministry at the Kaiser Wilhelm Institute for Flow Research at Goettingen.
Date: January 1944
Creator: Walchner, O.
Partner: UNT Libraries Government Documents Department

Vibration Survey of Blades in 19XB Axial-Flow Compressor 3: Preliminary Engine Investigation

Description: Strain gages were used to measure blade vibrations possibly causing failure in the 10-stage compressor of the 19XB jet-propulsion engine. The seventh and tenth stages were of great concern as a result of failures experienced by the manufacturer. Strain-gage records were obtained from all stages during acceleration, deceleration, and constant speed runs. Curves are presented herein showing the maximum allowable vibratory stress for a given speed, the change of the damping coefficient with the mounting of a strain gage at the base of the blade, the effect of rotor speed, on blade natural frequency, and the effect of the order of first bending-mode vibration on stress. It was found that for all stages the lower the order of vibration the higher the stress but no destructive vibrations were detected.
Date: January 28, 1948
Creator: Meyer, André J., Jr. & Calvert, Howard F.
Partner: UNT Libraries Government Documents Department

Theoretical Analysis of Stationary Potential Flows and Boundary Layers at High Speed

Description: "The present report consists of two parts. The first part deals with the two-dimensional stationary flow in the presence of local supersonic zones. A numerical method of integration of the equation of gas dynamics is developed. Proceeding from solutions at great distance from the body the flow pattern is calculated step by step" (p. 1).
Date: April 1948
Creator: Oswatitsch, K. & Wieghardt, K.
Partner: UNT Libraries Government Documents Department

The Boundary Layers in Fluids with Little Friction

Description: "The vortices forming in flowing water behind solid bodies are not represented correctly by the solution of the potential theory nor by Helmholtz's jets. Potential theory is unable to satisfy the condition that the water adheres at the wetted bodies, and its solutions of the fundamental hydrodynamic equations are at variance with the observation that the flow separates from the body at a certain point and sends forth a highly turbulent boundary layer into the free flow. Helmholtz's theory attempts to imitate the latter effect in such a way that it joins two potential flows, jet and still water, nonanalytical along a stream curve" (p. 1).
Date: February 1950
Creator: Blasius, H.
Partner: UNT Libraries Government Documents Department

Effect of Various Blade Modifications on Performance of a 16-Stage Axial-Flow Compressor 5 - Effect on Over-All Performance Characteristics of a 20-Percent Reduction in Solidity of the Fourteenth Through Sixteenth Stage Rotors

Description: The performance of a 16-stage axial-flow compressor, in which the mean-radius solidity was reduced from 1.28 to 1.02 in the fourteenth through sixteenth stage rotors was determined. The performance of this modification was compared with that of the compressor with original rotors. The reduced solidity resulted in slightly improved performance.
Date: April 21, 1952
Creator: Medeiros, Arthur A. & Hatch, James E.
Partner: UNT Libraries Government Documents Department

Effect of Air-Flow Distribution and Total-Pressure Loss on Performance of One-Sixth Segment of Turbojet Combuster

Description: "An investigation has been conducted on a one-sixth segment of an annular turbojet combustor to determine the effects of modification in air-flow distribution and total-pressure loss on the performance of the segment. The performance features investigated during this series of determinations were the altitude operational limits and the temperature-rise efficiency. Altitude operational limits of the combustor segment, for the 19XB engine using the original combustor-basket design were approximately 38,000 feet at 17,000 rpm and 26,000 feet at 10,000 rpm" (p. 1).
Date: December 10, 1947
Creator: Hill, Francis U. & Mark, Herman
Partner: UNT Libraries Government Documents Department

Measurements of Heat Transfer and Boundary-Layer Transition on an 8-Inch-Diameter Hemisphere-Cylinder in Free Flight for a Mach Number Range of 2.00 to 3.88

Description: "Measurements of aerodynamic heat transfer have been made along the hemisphere and cylinder of a hemisphere-cylinder rocket-propelled model in free flight up to a Mach number of 3.88. The test Reynolds number based on free-stream condition and diameter of model covered a range from 2.69 x l0(exp 6) to 11.70 x 10(exp 6). Laminar, transitional, and turbulent heat-transfer coefficients were obtained" (p. 1).
Date: April 18, 1957
Creator: Garland, Benjamine J. & Chauvin, Leo T.
Partner: UNT Libraries Government Documents Department

Heat Transfer Through Turbulent Friction Layers

Description: "The "general Prandtl number" Pr(exp 1) - A(sub q)/A Pr, aside from the Reynolds number determines the ratio of turbulent to molecular heat transfer, and the temperature distribution in turbulent friction layers. A(sub q) = exchange coefficient for heat; A = exchange coefficient for momentum transfer. A formula is derived from the equation defining the general Prandtl number which describes the temperature as a function of the velocity" (p. 1).
Date: September 1943
Creator: Reichardt, H.
Partner: UNT Libraries Government Documents Department

High-Subsonic Performance Characteristics and Boundary-Layer Investigations of a 12 10-Inch-Inlet-Diameter Conical Diffuser

Description: Performance and boundary-layer data were taken in a 12 degree 10-inch inlet-diameter conical diffuser of 2:1 exit- to inlet-area ratio. These data were taken for two inlet-boundary-layer conditions. The first condition was that of a thinner inlet boundary later (boundary-layer displacement thickness, delta* approximately equal to 0.034) produced by an inlet section approximately 1 inlet diameter in length between the entrance bell and the diffuser. The second condition was a thicker inlet boundary layer (delta* approximately equal to 0.120) produced by an additional inlet section length of approximately 6 diameters. Longitudinal static-pressure distributions were measured fro wall static orifices. Transverse total- and static-pressure surveys were made at the inlet and exit stations. Boundary-layer velocity distributions were measured at seven stations between the inlet and exit. These data were obtained for a Reynolds number (based on inlet diameter) range of 1 x 10(exp 6) to 3.9 x 10(exp 6). The corresponding Mach number range was from M = 0.2 to choking. At the maximum-power-available condition supersonic flow was obtained as far as 4.5 inches downstream from the diffuser inlet with a maximum Mach number of M approximately equal to 1.5. The total-pressure loss through the diffuser in percentage of inlet dynamic pressure was approximately 2.5 percent for the thinner inlet boundary later and 5.5 percent for the thicker inlet boundary later over the lower subsonic range. These valued increased with increasing flow rate- the values for the thicker inlet boundary later more than those for the thinner inlet boundary layer. The diffuser effectiveness, expressed as the ratio of the actual static-pressure rise to the ideal static-pressure rise, was about 85 percent for the thinner inlet boundary layer and about 67 percent for the thicker inlet boundary later in the lower subsonic range. These values decrease with increasing flow rate. Separated flow ...
Date: May 11, 1950
Creator: Little, B. H., Jr. & Wilbur, Stafford W.
Partner: UNT Libraries Government Documents Department

General Characteristics of the Flow through Nozzles at Near Critical Speeds

Description: The characteristics of the position and form of the transition surface through the critical velocity are computed for flow through flat and round nozzles from subsonic to supersonic velocity. Corresponding considerations were carried out for the flow about profiles in the vicinity of sonic velocity.
Date: June 1947
Creator: Sauer, R.
Partner: UNT Libraries Government Documents Department

The Principles of Turbulent Heat Transfer

Description: "The literature on turbulent heat transfer has in the course of years attained a considerable volume. Since this very complicated problem has not as yet found a complete solution, further studies in this field may be expected. The heat engineer must therefore accommodate himself to a constantly increasing number of theories and formulas. Since the theories generally start from hypothetical assumptions, and since they contain true and false assertions, verified knowledge and pure suppositions often being intermingled in a manner difficult to tell them apart, the specialist had difficulty in forming a correct evaluation of the individual studies" (p. 1).
Date: September 1957
Creator: Reichardt, H.
Partner: UNT Libraries Government Documents Department