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Theoretical Investigation of Submerged Inlets at Low Speeds

Description: From Summary: "The general characteristics of the flow field in a submerged air inlet are investigated by theoretical, wind-tunnel, and visual-flow studies. Equations are developed for calculating the laminar and turbulent boundary-layer growth along the ramp floor for parallel, divergent, and convergent ramp walls, and a general equation is derived relating the boundary-layer pressure losses to the boundary-layer thickness. It is demonstrated that the growth of the boundary layer on the floor … more
Date: August 1951
Creator: Sacks, Alvin H. & Spreiter, John R.
Partner: UNT Libraries Government Documents Department
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Determination of Shapes of Boattail Bodies of Revolution for Minimum Wave Drag

Description: "By use of an approximate equation for the wave drag of slender bodies of revolution in a supersonic flow field, the optimum shapes of certain boattail bodies are determined for minimum wave drag. The properties of three specific families of bodies are determined, the first family consisting of bodies having a given length and base area and a contour passing through a prescribed point between the nose and base, the second family having fixed length, base area, and maximum area, and the third fa… more
Date: August 21, 1951
Creator: Adams, Mac C.
Partner: UNT Libraries Government Documents Department
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Heat Delivery in a Compressible Flow and Applications to Hot-Wire Anemometry

Description: Note presenting the development of a generalized potential theory applicable to nonadiabatic and rotational flow in a two-dimensional field. Three partial differential equations are obtained determining the three variables. which are distribution of additional temperature, velocity perturbation, and an auxiliary function characterizing the rotationality of the flow. Application of the results to hot-wire anemometry are discussed.
Date: August 1951
Creator: Tchen, Chan-Mou
Partner: UNT Libraries Government Documents Department
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An Investigation of Aircraft Heaters 34: Experimental Determination of Thermal and Hydrodynamical Behavior of Air Flowing Between a Flat and a Wave-Shaped Plate

Description: Report presenting an investigation of the thermal and hydrodynamical behavior of air flowing along a passage with one flat side, which was steam-heated, and one wave-shaped side, which was unheated. Two series of tests were conducted, one with the plates in direct opposition and one with the plates slightly separated, which induced turbulence upstream of the thermal boundary layer. Results regarding heat transfer and static-pressure drop are provided.
Date: August 1951
Creator: Boelter, L. M. K.; Sanders, V. D.; Young, G.; Morgan, M. & Morrin, E. H.
Partner: UNT Libraries Government Documents Department
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An investigation of aircraft heaters 36: preliminary investigation of a combustion-type aircraft heater

Description: Report presenting experimental results on the thermal performance of an aircraft combustion-type heater. The performance of the heater with a counterflow and a parallel-flow return passage on the gas side does not appear predictable by use of existing equations. The thermal conductance for the gases within the combustion chamber is predicted to be many times lower than the experimental data indicate.
Date: August 1951
Creator: Boelter, L. M. K.; Elswick, W. R.; Sanders, V. D. & Rubesin, M. W.
Partner: UNT Libraries Government Documents Department
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Effect of Stress-Solvent Crazing on Tensile Strength of Polymethyl Methacrylate

Description: Note presenting an investigation of the loss of strength of tensile specimens of polymethyl methacrylate as a result of stress-solvent crazing at 23 degrees Celsius and 50-percent relative humidity. the materials tested were commercial cast polymethyl-methacrylate sheets of both heat-resistant and ordinary grades from each of two manufacturers.
Date: August 1951
Creator: Axilrod, B. M. & Sherman, Martha A.
Partner: UNT Libraries Government Documents Department
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Statistical Fluctuation of Intensity in Debye-Scherrer Lines Due to Random Orientation of Crystal Grains

Description: Note presenting an exploration of the Debye-Scherrer diagram of a stationary polycrystalline sample, which has an intensity distribution with an erratic line because of statistical irregularities of the crystal grain orientation. The fluctuations of intensity are discussed for the case that the only causes of line breadth are the natural spectral width of the primary radiation and the finite size of the grains.
Date: August 1951
Creator: Ekstein, Hans
Partner: UNT Libraries Government Documents Department
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Kinetics of sintering chromium carbide

Description: Report presenting an investigation of the sintering of chromium carbide under pressure in order to study the kinetics of grain growth and densification during this process. Densification of a sintered chromium carbide compact was accompanied by grain growth and density and grain size seem to be interdependent during this stage of the sintering process.
Date: August 1951
Creator: Lidman, William G. & Hamjian, H. J.
Partner: UNT Libraries Government Documents Department
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Skin Friction of Incompressible Turbulent Boundary Layer Under Adverse Pressure Gradients

Description: Note presenting experimental data for skin friction of turbulent boundary layers under adverse pressure gradients from several sources in graphical form. Data obtained by the momentum-balance method are shown to follow a trend opposite to that of data obtained by hot-wire and heat-transfer methods.
Date: August 1951
Creator: Goldschmied, Fabio R.
Partner: UNT Libraries Government Documents Department
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A Critical Review of Notch Sensitivity in Stress-Rupture Tests

Description: Note presenting a review of English and German literature on notch stress-rupture data, which included the effect of notching on rupture strength in general, the effect of chemical composition and heat treatment on notch stress-rupture characteristics, the mechanism of stress-rupture embrittlement and notch sensitivity in low-alloy steels, and a comparison of the influence of notch geometry on notch strength in stress-rupture tests and in conventional tensile tests.
Date: August 1951
Creator: Brown, W. F., Jr. & Sachs, George
Partner: UNT Libraries Government Documents Department
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A biharmonic relaxation method for calculating thermal stress in cooled irregular cylinders

Description: Report presenting a numerical method for calculating thermal stresses in irregular cylinders cooled by one or more internal passages. The use of relaxation methods and elementary methods of finite differences was found to give approximations to correct values when compared with previously known solutions for concentric circular cylinders with symmetrical and asymmetrical temperature distributions.
Date: August 1951
Creator: Holms, Arthur G.
Partner: UNT Libraries Government Documents Department
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Some Measurements of the Effect of Gaseous Imperfections on the Critical Pressure Ratio in Air and the Speed of Sound in Nitrogen

Description: Note presenting experiments made to measure the speed of sound in nitrogen at room temperatures in the pressure range of 0 to 2000 pounds per square inch, and the critical pressure ratio of air expanded isentropically from stagnation conditions in the same range. The experimental results were compared with values obtained by using the Van der Waals equation and the Beattie-Bridgeman equation.
Date: August 1951
Creator: Donaldson, Coleman duP. & Jones, Jim J.
Partner: UNT Libraries Government Documents Department
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Wind-tunnel investigation and analysis of the effects of end plates on the aerodynamic characteristics of an unswept wing

Description: Report presenting a wind-tunnel investigation to determine the effects of end plates of various areas and shapes on the aerodynamic characteristics of an unswept and untapered wing of aspect ratio 4. End plates were found to provide the basic wing with an increase in the lift-curve slope, a reduction in the induced drag, and an increase in the maximum lift coefficient.
Date: August 1951
Creator: Riley, Donald R.
Partner: UNT Libraries Government Documents Department
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Further comparisons of theoretical and experimental lift and pressure distributions on airfoils in cascade at low-subsonic speed

Description: Report presenting comparisons of theoretical and experimental lift coefficients and pressure distributions for five compressor-type cascades of highly cambered NACA 6-series airfoils. The experimental lift coefficients were generally less than the theoretical values for the same mean-flow direction. A justification of the experimental and analytical methods are also provided.
Date: August 1951
Creator: Katzoff, Samuel & Hannah, Margery E.
Partner: UNT Libraries Government Documents Department
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Transformations of the Hodograph Flow Equation and the Introduction of Two Generalized Potential Functions

Description: Note presenting some sets of solutions studied independently of the gas laws and some properties of the series obtained by means of these sets. The equations have been further transformed so as to have as independent variables the complex velocity and the complex mass velocity.
Date: August 1951
Creator: Crocco, Luigi
Partner: UNT Libraries Government Documents Department
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Heat transfer to bodies in a high-speed rarefied-gas stream

Description: Report presenting measurements of the equilibrium temperature and heat-transfer coefficients for transverse cylinders in a high-speed stream of rarefied gas over a range of Knudsen and Mach numbers. Results regarding the temperature recovery for an insulated body and heat-transfer-test results are provided.
Date: August 1951
Creator: Stalder, Jackson R.; Goodwin, Glen & Creager, Marcus O.
Partner: UNT Libraries Government Documents Department
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A Photoelastic Investigation of Stress Concentrations Due to Small Fillets and Grooves in Tension

Description: "Factors of stress concentration for deep, sharp, and symmetrically arranged grooves and fillets in tension members have been determined photoelastically and are given in this report. Curves are given showing the distribution of principal stresses on the section through the grooves. Complete isopachic patterns for several basic cases of grooved bars are included" (p. 1).
Date: August 1951
Creator: Frocht, M. M.
Partner: UNT Libraries Government Documents Department
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The similarity law for hypersonic flow about slender three-dimensional shapes

Description: Report presenting the use of the similarity law to determine simple expressions for correlating the forces and moments acting on related shapes operating at hypersonic speeds. The shapes considered are wings, bodies, and wing-body combinations.
Date: August 1951
Creator: Hamaker, Frank M.; Neice, Stanford E. & Eggers, A. J., Jr.
Partner: UNT Libraries Government Documents Department
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Tabulated Pressure Coefficients and Aerodynamic Characteristics Measured in Flight on the Wing of the D-558-I Research Airplane Through a Mach Number Range of 0.80 to 0.89 and Throughout the Normal-Force-Coefficient Range at Mach Numbers of 0.61, 0.70, 0.855, and 0.88

Description: "Tabulated pressure coefficients and aerodynamic characteristics obtained in flight from pressure distributions over six chordwise rows of orifices on the right wing of the D-558-I research airplane (BuAero No. 37972) are presented. The data were obtained through a Mach number range of 0.80 to 0.89 and throughout the normal-force-coefficient range at Mach numbers of 0.61, 0.70, 0.855, and 0.88. This paper supplements similar tabulated data which have been presented in NACA RM L50J10 and NACA RM… more
Date: August 20, 1951
Creator: Keener, Earl R. & Bandish, Rozalia M.
Partner: UNT Libraries Government Documents Department
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Some low-speed characteristics of an air-induction system having scoop-type inlets with provisions for boundary-layer control

Description: Report presenting an investigation conducted at low speed of an air-induction system with twin scoop-type inlets on the sides of the fuselage of a model of an airplane designed for flight at supersonic Mach numbers. The leading edge of the lip of the scoop was rounded and there were provisions for control of the boundary layer ahead of the inlet. Results regarding the characteristics of the lips investigated, characteristics of the main duct with lip E, characteristics of the boundary layer con… more
Date: August 28, 1951
Creator: Watson, Earl C.
Partner: UNT Libraries Government Documents Department
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Tank investigation of the Grumman JRF-5 airplane with a single hydro-ski and an extended afterbody

Description: Report presenting results from a tank investigation of a powered dynamic model of the Grumman JRF-5 airplane fitted with a single hydro-ski and extended afterbody. Results indicated that the afterbody extension in place of a tail ski reduced the maximum resistance by 10 percent. Removal of the wing-tip skids gave a further reduction in maximum resistance of 3 percent.
Date: August 7, 1951
Creator: Ramsen, John A. & Gray, George R.
Partner: UNT Libraries Government Documents Department
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Stability and control characteristics at low speed of a 1/5-scale model of the Edo 142 hydro-ski research airplane

Description: Report presenting an investigation in the 300 mph tunnel to determine the low-speed stability and control characteristics and the jet-engine duct-inlet pressure recovery characteristics of a model of the Edo 142 hydro-ski research airplane. Results regarding the longitudinal stability and control, stall-control devices, alighting gear, lateral stability, directional control, lateral control, and duct pressure recovery are provided.
Date: August 6, 1951
Creator: Riebe, John M.; MacLeod, Richard G. & Moseley, William C., Jr.
Partner: UNT Libraries Government Documents Department
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Investigation of mechanisms of blade failure of forged Hastelloy B and cast Stellite 21 turbine blades in turbojet engine

Description: An investigation was conducted to study the mechanisms of blade failure of forged Hastelloy B and cast Stellite 21. The blades were mounted in a 16-25-6 alloy rotor and subjected to 20-minute cycles consisting of 15 minutes at rated speed and approximately 5 minutes at idle. The first failures of the Hastelloy B and Stellite 21 blades were probably the result of excessive vibratory stresses and occurred after 14.25 and 16.75 hours, respectively. After 28.75 hours of operation, all but 3 of the … more
Date: August 22, 1951
Creator: Yaker, C.; Robards, C. F. & Garrett, F. B.
Partner: UNT Libraries Government Documents Department
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