Serial/Series Title
343 Matching Results
Results open in a new window/tab.
Large Deflection of Curved Plates
Report presenting a treatment of several problems on the large deflections of curved plates with compound curvature. Testing demonstrated that the effective width of the curved plates in longitudinal compression is reduced by the presence of an initial deflection function.
Date:
October 1956
Creator:
Lew, H. G.; Fox, J. A. & Loo, T. T.
System:
The UNT Digital Library
Heat-transfer measurements on two bodies of revolution at a Mach number of 3.12
Report presenting local rates of heat transfer obtained from a parabolic-nosed cylinder at Mach number 3.12. The laminar-heat-transfer coefficients obtained from the conical portion of the cone cylinder were found to agree closely with theory at all temperature levels when corrected for the axial temperature distribution.
Date:
October 1956
Creator:
Jack, John R. & Diaconis, N. S.
System:
The UNT Digital Library
Seat Design for Crash Worthiness
Technical note presenting a simplified model of a crash deceleration pulse that incorporates the essential properties of the pulse. The model pulse is considered to be made up of a base pulse on which are superimposed one or more secondary pulses of shorter duration. Data are presented from full-scale laboratory and crash studies on the deceleration loads measured on dummy passengers in seats of standard and novel design.
Date:
October 1956
Creator:
Pinkel, I. Irving & Rosenberg, Edmund G.
System:
The UNT Digital Library
Near noise field of a jet-engine exhaust 1: sound pressures
Report presenting information about the acoustical near field produced by the exhaust of a stationary turbojet engine with a high pressure ratio measured for a single operating condition without afterburning. Additional testing was made at a few points to determine the difference in value between sound-pressure levels at rigid surfaces and corresponding free-field values. Results regarding overall sound pressure, sound-pressure level in frequency bands, sound-pressure-level spectra along jet boundary, and second-source noise are provided.
Date:
October 1956
Creator:
Howes, Walton L. & Mull, Harold R.
System:
The UNT Digital Library
Aerodynamic characteristics of 15 NACA airfoil sections at seven Reynolds numbers from 0.7 x 10(exp 6) to 9.0 x 10(exp 6)
Report presenting an investigation of the two-dimensional aerodynamic characteristics of 15 NACA airfoils at four Reynolds numbers. The results indicate that the drag coefficient at the design lift coefficient and the maximum lift coefficient are the most important aerodynamic characteristics and are most affected by Reynolds number changes.
Date:
October 1949
Creator:
Loftin, Laurence K., Jr. & Smith, Hamilton A.
System:
The UNT Digital Library
Two matrix methods for calculating forcing functions from known responses
Report presenting an analysis of two matrix methods for calculating responses of linear systems for given forcing functions and indicial responses in order to find a method suitable for solving the inverse problem of calculating forcing functions from known responses. The results of both methods are compared with exact solutions for both the direct and the inverse problems.
Date:
October 1949
Creator:
Mazelsky, Bernard & Diederich, Franklin W.
System:
The UNT Digital Library
Plastic buckling of extruded composite sections in compression
From Summary: "The theory of plastic buckling, originally derived for individual plates, has been extended to apply to combinations of plates such as H- and Z-sections. The theory has been applied specifically to extruded H-sections of 75S-T6 aluminum alloy; the calculated buckling stresses agree satisfactorily with the stresses obtained experimentally."
Date:
October 1949
Creator:
Stowell, Elbridge Z. & Pride, Richard A.
System:
The UNT Digital Library
Investigations relating to the extension of laminar flow by means of boundary-layer suction through slots
Report presenting an experimental investigation of boundary-layer suction through slots as a means of increasing the extent of laminar flow on airfoil sections. Results regarding slot geometry and arrangement, suction slots in an unfavorable pressure gradients, suction slots in a favorable pressure gradient, and a determination of the relations controlling the distribution of suction slots are provided.
Date:
October 1949
Creator:
Loftin, Laurence K., Jr. & Burrows, Dale L.
System:
The UNT Digital Library
Critical Shear Stress of a Curved Rectangular Panel With a Central Stiffener
"A theoretical solution is given for the critical shear stress of a simply supported curved rectangular plate stiffened by a central stiffener offering no torsional restraint which lies in either the axial or circumferential direction. Results are obtained by means of the Galerkin method and are presented in the form of computed curves and tables" (p. 1).
Date:
October 1949
Creator:
Stein, Manuel & Yaeger, David J.
System:
The UNT Digital Library
Theoretical spanwise lift distributions of low-aspect-ratio wings at speeds below and above the speed of sound
From Summary: "The spanwise lift distributions of wings of low aspect ratio but of arbitrary plan form and angle-of-attack distribution have been analyzed by two well-established concepts: the virtual-mass concept and the Weissinger method. Both concepts have been found to yield the same simple integral expression for the spanwise lift distribution in terms of the spanwise angle-of-attack distribution. Tables and figures of lit distributions of low-aspect-ratio wings have been presented."
Date:
October 1949
Creator:
Diederich, Franklin W. & Zlotnick, Martin
System:
The UNT Digital Library
Summary of the theoretical lift, damping-in-roll, and center-of-pressure characteristics of various wing plan forms at supersonic speeds
Report presenting information for the determination of the theoretical lift, damping-in-roll, and center-of-pressure characteristics for a group of plan forms at supersonic speeds. The information is presented in three forms: equations, figures presenting generalized curves, and figures presenting curves for representative groups of configurations. Several observations are made in regards to the effect of taper ratio, angle of sweep, and aspect ratio on the values of the derivatives.
Date:
October 1949
Creator:
Piland, Robert O.
System:
The UNT Digital Library
A factor affecting transonic leading-edge flow separation
Report presenting a change in flow pattern that was observed as the free-stream Mach number was increased in the vicinity of 0.8. The paper presents an investigation of the consequences of shock-wave-boundary-layer interaction, which are proposed as a factor that may be important in determining the conditions under which the change in flow pattern occurs.
Date:
October 1956
Creator:
Wood, George P. & Gooderum, Paul B.
System:
The UNT Digital Library
A method for predicting the upwash angles induced at the propeller plane of a combination of bodies with an upswept wing
Report presenting a method for predicting the upwash angles induced at the horizontal center line of the propeller disk of a particular twin-gate engine. The boundary conditions of the airship theory used to predict the upwash angles due to the nacelle of the airplanes was not strictly satisfied. Results regarding the evaluation of the method, application of the method to similar configurations, and extension of the method to dissimilar configurations are provided.
Date:
October 1951
Creator:
Yaggy, Paul F.
System:
The UNT Digital Library
Calculation of the forces and moments on a slender fuselage and vertical fin penetrating lateral gusts
A theory is presented for calculating the variation with frequency of the lateral-force and yawing-moment coefficients due to sinusoidal side gusts passing over the profile of a simple fuselage-vertical-fin combination. The analysis is based on slender-body theory. The method considers the penetration effect of both fuselage and vertical tail in calculating side force and yawing moment due to side gusts, as opposed to a simple lag concept which considers the flow angle to be uniform over the configuration.
Date:
October 1956
Creator:
Eggleston, John M.
System:
The UNT Digital Library
Secondary Stresses in Thin-Walled Beams With Closed Cross Sections
Note presenting an accurate method of determining secondary stresses in thin-walled, uniform beams of closed cross section. In the first part of the report, the integrodifferential equation governing axial displacements is formulated and solved for a beam without longitudinal stiffeners. In the second part, the corresponding summation-difference equation is developed and solved for a beam with stiffeners.
Date:
October 1951
Creator:
Benscoter, Stanley Urner
System:
The UNT Digital Library
Conversion of Inviscid Normal-Force Coefficients in Helium to Equivalent Coefficients in Air for Simple Shapes at Hypersonic Speeds
A correlation factor applicable for converting inviscid aerodynamic normal-force coefficients of simple shapes in helium to equivalent coefficients in air is found by using calculations based on the shock-expansion method at Mach numbers of 12, 16, and 20.
Date:
October 1956
Creator:
Mueller, James N.
System:
The UNT Digital Library
A Theoretical Estimate of the Effects of Compressibility on the Performance of a Helicopter Rotor in Various Flight Conditions
The effects of compressibility arising from high-tip-speed operation on the flapping, thrust, and power of a helicopter rotor in forward speed are investigated for a particular set of airfoil characteristics. Tip-speed ratios ranging from 0.2 to 0.5 were covered at several tip-speed values.
Date:
October 1956
Creator:
Gessow, Alfred & Crim, Almer D.
System:
The UNT Digital Library
An Investigation of the Loads on the Vertical Tail of a Jet-Bomber Airplane Resulting From Flight Through Rough Air
"Vertical-tail loads were measured in turbulent air on a four-engine jet bomber. Results showed large load oscillations which were lightly damped. Comparison of experimental results with discrete-load calculations indicated that discrete-gust calculations underestimated the loads by 30 to 40 percent and gave no indication of the low damping. Power spectral analysis, on the other hand, indicated the general frequency characteristics and gave a somewhat better estimate of the peak-load distributions" (p. 1).
Date:
October 1956
Creator:
Funk, Jack & Rhyne, Richard H.
System:
The UNT Digital Library
Heat-Capacity Measurements of Titanium and of a Hydride of Titanium for Temperatures From 4 to 15 K Including a Detailed Description of a Special Adiabatic Specific-Heat Calorimeter
Note presenting a description of an adiabatic specific-heat calorimeter bridging the interval between 4 and 15 degrees Kelvin temperatures. The instrument uses a constant-volume helium gas thermometer as the working thermometer. The instrument is tested on an alloy and a sample of pure titanium and the results are described.
Date:
October 1956
Creator:
Aven, M. H.; Craig, R. S. & Wallace, W. E.
System:
The UNT Digital Library
An air-flow-direction pickup suitable for telemetering use on pilotless aircraft
From Summary: "A free-swiveling vane-type pickup for measuring air flow direction in both the angle-of-attack and angle-of-sideslip directions is described. Test results are presented which indicate that the pickup is aerodynamically stable and has an accuracy, obtained from a bench calibration, of better than 0.3^o under conditions including acceleration up to 20g in any direction, Mach numbers from 0.5 to 2.8, dynamic pressures up to at least 65 psi. Equations and curves which can be used to obtain flow direction at the center of gravity of a maneuvering model are presented."
Date:
October 1956
Creator:
Ikard, Wallace L.
System:
The UNT Digital Library
Experimental investigation of a lightweight rocket chamber
From Summary: "Experiments have been conducted with a jacketed rocket combustion chamber that was fabricated by hydraulic forming from sheet metal. Rocket combustion chambers made by this method have been used successfully. Runs with these combustion chambers have been made at overall heat-transfer rates of 2.5 Btu per square inch per second with water cooling and also with ammonia as a regenerative coolant."
Date:
October 1956
Creator:
Dalgleish, John E. & Tischler, Adelbert O.
System:
The UNT Digital Library
Exploratory investigation of the effectiveness of biplane wings with large-chord double slotted flaps in redirecting a propeller slipstream downward for vertical take-off
Results are presented from static-force tests on biplane wings with large-chord double slotted flaps which turn the slipstream of a single counter rotating propeller downward for vertical take-off. The investigation provided information on the effect of chord length, flap deflection, propeller position, end plates, fuselage, and ground proximity on the efficiency of the wing system in turning the propeller slipstream.
Date:
October 1956
Creator:
Kirby, Robert H.
System:
The UNT Digital Library
Simplified method for calculation of compressible laminar boundary with arbitrary free-stream pressure gradient
Report presenting a simplification of the Karman-Polhausen integral method as applied to compressible laminar boundary layers. The analysis was conducted under the assumptions of a Prandtl number of 1, zero heat transfer, and a linear viscosity-temperature relation.
Date:
October 1951
Creator:
Low, George M.
System:
The UNT Digital Library
Laminar friction and heat transfer at Mach numbers from 1 to 10
Velocity and temperature profiles and laminar boundary-layer characteristics have been computed for Mach numbers from 1 to 10, utilizing experimental values of the heat capacity, viscosity, and conductivity. The analysis shows that effective temperature, which is a function of the surface temperature and stream conditions, arises naturally and is the proper reference temperature to be used in heat-transfer calculations. The effective temperature and the recovery temperature become identical for the condition of zero heat transfer.
Date:
October 1951
Creator:
Klunker, E. B. & McLean, F. Edward
System:
The UNT Digital Library