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Two-Dimensional Irrotational Transonic Flows of a Compressible Fluid

Description: The methods of NACA TN No. 995 have been slightly modified and extended in include flows with circulation by considering the alteration of the singularities of the incompressible solution due to the presence of the hypergeometric functions in the analytic continuation of the solution. It was found that for finite Mach numbers the only case in which the nature of the singularity can remain unchanged is for a ratio of specific heats equal to -1. From a study of two particular flows it seems that … more
Date: June 1948
Creator: Kuo, Yung-Huai
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tables and charts of flow parameters across oblique shocks

Description: Shock-wave equations have been evaluated for a range of Mach number in front of the shock from 1.05 to 4.0. Mach number behind the shock, pressure ratio, derivation of flow, and angle of shock are presented on charts. Values are also included for density ratio and change in entropy.
Date: August 1948
Creator: Neice, Mary M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Two-dimensional subsonic compressible flows past arbitrary bodies by the variational method

Description: Instead of solving the nonlinear differential equation which governs the compressible flow, an approximate method of solution by means of the variational method is used. The general problem of steady irrotational flow past an arbitrary body is formulated. Two examples were carried out, namely, the flow past a circular cylinder and the flow past a thin curved surface. The variational method yields results of velocity and pressure distributions which compare excellently with those found by existi… more
Date: March 1951
Creator: Wang, Chi-Teh
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Principal Effects of Axial Load on Moment-Distribution Analysis of Rigid Structures

Description: "This thesis presents the method of moment distribution modified to include the effect of axial load upon the bending moments. This modification makes it possible to analyze accurately complex structures, such as rigid fuselage trusses, that heretofore had to be analyzed by approximate formulas and empirical rules. The method is simple enough to be practicable even for complex structures, and it gives a means of analysis for continuous beams that is simpler than the extended three-moment equati… more
Date: July 1935
Creator: James, Benjamin Wylie
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A General Method of Selecting Foam Inhibitors

Description: Note presenting a criterion for selecting foam inhibitors from insoluble liquids that form emulsions with the foaming liquid. By determining the surface tensions of the foaming liquid and of the additive saturated with that liquid and the interfacial tension between them, spreading and entering coefficients may be calculated. A mechanism of foam inhibition is also described.
Date: May 1946
Creator: Robinson, J. V. & Woods, W. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Notes on the Foundations of the Theory of Small Displacements of Orthotropic Shells

Description: Note presenting a survey that has been made of the various systems of equations which have been given in the literature for the analysis of small deflections of thin elastic shell. A new system of equations has been derived for the analysis of shells, which includes the effects of transverse shear and normal stresses.
Date: March 1949
Creator: Hildebrand, F. B.; Reissner, E. & Thomas, G. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Metallurgical Investigation of Large Forged Discs of Low-Carbon N-155 Alloy

Description: Research was undertaken to ascertain the properties of better wrought heat resisting alloys in the form of large discs required for gas turbine rotors. The properties of large discs of low carbon N-155 alloy in both the as-forged and water-quenched and aged conditions were determined by means of stress-rupture and creep tests for time periods up to about 2000 hours at 1200, 1350, and 1500 F. Short-time tensile test, impact test, and time-total deformation characteristics are included.
Date: April 1947
Creator: Cross, Howard C. & Freeman, J. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of Catalysts and pH Strength of Resin-Bonded Plywood

Description: Report presenting the effects of various catalysts used to cure resinous adhesives on the strength properties of plywood, especially in regard to the degree of solidity developed by the catalysts in the resin film and the plywood. Six resins were tested with birch wood, which is the most commonly used wood in aircraft construction.
Date: April 1947
Creator: Kline, G. M.; Reinhart, F. W.; Rinker, R. C. & De Lollis, N. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Limits of Precision in the Determination of Lattice Parameters and Stresses by the Debye-Scherrer Method

Description: Note an investigation regarding the limits of precision in the determination of lattice parameters. Experiments were performed with copper radiation on zinc samples. Even when the crystal-grain orientation is perfectly uniform, the recording of the intensity distribution will entail errors.
Date: October 1947
Creator: Ekstein, Hans & Siegel, Stanley
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Axial fatigue tests at zero mean stress of 24S-T and 75S-T aluminum-alloy strips with a central circular hole

Description: From Summary: "Axial fatigue tests at zero mean stress have been made on 0.032- and 0.064-inch 24S-T and 0.032-inch 75S-T sheet-metal specimens 1/4, 1/2, 1, and 2 inches wide without a hole and with central holes giving a range of hole diameter D to specimen width W from 0.01 to 0.95. No systematic difference was noted between the results for the 0.032-inch and the 0.064-inch specimens although the latter seemed the more consistent. In general the fatigue strength based on the minimum section d… more
Date: August 1948
Creator: Brueggeman, W. C. & Mayer, M., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Laminar Boundary Layer in Compressible Fluids Using the Crocco Method

Description: Note presenting the use of the Crocco method to solve the simultaneous differential equations of momentum and energy involved in the flow of air in a thin laminar boundary layer on a flat plate. The Crocco method was used because it gave accurate results for arbitrary Prandtl number near unity. Variations of shear, velocity, temperature, and Mach number across the boundary layer are included.
Date: January 1952
Creator: Van Driest, E. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of Range of Stress and of Special Notches on Fatigue Properties of Aluminum Alloys Suitable for Airplane Propellers

Description: "Laboratory tests were made to obtain information on the load-resisting properties of X76S-T aluminum alloy when subjected to static, impact, and repeated loads. Results are presented from static-load test of unnotched specimens in tension and in torsion and of notched specimens in tension. Charpy impact values obtained from bend tests on notched specimens and tension impact values for both notched and unnotched specimens tested at several different temperatures are included" (p. 1).
Date: June 1942
Creator: Dolan, Thomas J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Survey of Background and Aircraft Noise in Communities Near Airports

Description: Note presenting the results of a survey of background and aircraft noise levels in residential communities in eight cities with major airports. The measurements were made in areas up to 12 miles away from the airports and were located in regularly used flight paths. The results indicated that there is a range of more than 20 decibels in the average background noise in the 180 areas included in the survey.
Date: December 1954
Creator: Stevens, K. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrodynamic Investigation of a Series of Hull Models Suitable for Small Flying Boats and Amphibians

Description: Note presenting the results of an investigation to obtain hydrodynamic information on a series of hull models suitable for small flying boats or amphibians of from 2000 to 5000 pounds gross weight. The series of hulls consisted of a basic hull with simple lines, and of plus and minus variations to the design in which the beam, stern-post angle, and afterbody length were altered. The results show that it is possible to design a hull with simple lines that will be suitable for small flying boats … more
Date: November 1951
Creator: Hugli, W. C., Jr. & Axt, W. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Plastic Stress-Strain Relations for Combined Tension and Compression

Description: Note presenting an investigation to determine the validity of the plasticity theories and the correctness of various assumptions made in these theories. Plastic stress-strain relations for biaxial tension-compression principal stresses were determined for a 14S-T4 aluminum alloy. Since the constant-stress-ratio tests cannot distinguish between the flow and deformation theories, variable-stress-ratio tests and special biaxial tests were conducted.
Date: July 1952
Creator: Marin, Joseph & Wiseman, H. A. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tests of Bonded and Riveted Sheet-Stringer Panels

Description: Note presenting tests performed on 21 sheet-stringer panels of 75S-T6 aluminum alloy with alclad sheets nominally 0.051 inch thick and stringers nominally 3.5 inches apart. Three panels of different types, with five stringers each and overall dimensions of approximate 18 by 15 inches, were tested in axial flat-end compression. Results regarding the flat-end compression, protruding-stringer compression, and bending are provided.
Date: June 1954
Creator: Mordfin, Leonard & Wilks, I. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cooperative Investigation of Relationship Between Static and Fatigue Properties of Wrought N-155 Alloy at Elevated Temperatures

Description: Note presenting extensive data relating properties of wrought N-155 alloy under static, combined static and dynamic, and completed reversed dynamic stress conditions. Time periods for fracture ranged from 50 to 500 hours at room temperatrue, 1000, 1200, 1350, and 1500 degrees Fahrenheit. Results regarding the rupture and fatigue strengths, fatigue strengths based on cycles to failure, influence of superimposed fatigue loads on creep, influence on superimposed fatigue stress on elongation in the… more
Date: April 1955
Creator: NACA Subcommittee on Heat-Resisting Materials
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transonic Flow Past Cone Cylinders

Description: Note presenting experimental results for transonic flow past cone-cylinder, axially symmetric bodies. The drag coefficient and surface Mach number are studied as the free-stream Mach number is varied and, wherever possible, the experimental results are compared with theoretical predictions. The theoretical problem of transonic flow past finite cones is discussed briefly and an approximate solution of the axially symmetric transonic equations, valid for a semi-infinite cone, is presented.
Date: September 1954
Creator: Solomon, George E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Landing-Gear Impact

Description: Report deals with the impact forces in landing gears. Both the landing impact and the taxiing impact have been considered, but drag forces have so far been excluded. The differential equations are developed and their numerical integration is shown, considering the nonlinear properties of the oleo shock strut. A way is shown for determining the dimensions of the metering pin from a given load-time diagram. A review of German literature on landing-gear impact is also presented.
Date: October 1952
Creator: Flügge, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Theoretical and Experimental Investigation of Random Gust Loads Part 1: Aerodynamic Transfer Function of a Simple Wing Configuration in Incompressible Flow

Description: Sinusoidally oscillating downwash and lift produced on a simple rigid airfoil were measured and compared with calculated values. Statistically stationary random downwash and the corresponding lift on a simple rigid airfoil were also measured and the transfer functions between their power spectra determined. The random experimental values are compared with theoretically approximated values. Limitations of the experimental technique and the need for more extensive experimental data are discussed.
Date: May 1957
Creator: Hakkinen, Raimo J. & Richardson, A. S., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On the Development of Turbulent Wakes from Vortex Streets

Description: "Wake development behind circular cylinders at Reynolds numbers from 40 to 10,000 was investigated in a low-speed wind tunnel. Standard hotwire techniques were used to study the velocity fluctuations. The Reynolds number range of periodic vortex shedding is divided into two distinct subranges. At R = 40 to 150, called the stable range, regular vortex streets are formed and no turbulent motion is developed" (p. 1).
Date: March 1953
Creator: Roshko, Anatol
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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