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Solutions of laminar-boundary-equations which result in specific-weight-flow profiles locally exceeding free-stream values

Description: Revised solutions of the laminar-boundary-layer equations for cases which involved cooling at the wall combined with large pressure gradients in the main stream produced specific-weight-flow profiles which locally exceeded free-stream values. Heat-transfer and friction coefficients, boundary-layer thicknesses, and velocity, temperature, and specific-weight-flow distributions resulting from the revised solutions are presented for Euler numbers of 0.5 and 1, stream-to-wall temperature ratios of 2 and 4, and cooling-air flow rates through porous walls designated by flow parameters of 0, -0.5, and -1.
Date: September 1952
Creator: Brown, W. Byron & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department
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Survey of the acoustic near field of three nozzles at a pressure ratio of 30

Description: The sound pressures radiating from the exhaust streams of two convergent-divergent and one convergent nozzle were measured. Exit diameters were 1.206 in. for the expanded nozzle and 0.625 in. for the convergent nozzle. The results are presented in a series of contour maps of overall and fine 1/3-octave-band sound pressures. The location of the source of the noise in each 1/3-octave band in the frequency range of 30 to 16,000 cps and the total power radiated were determined and compared with those of subsonic jets.
Date: April 1957
Creator: Mull, Harold R. & Erickson, John C., Jr.
Partner: UNT Libraries Government Documents Department
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A Study of the Stability of the Laminar Boundary Layer as Affected by Changes in the Boundary-Layer Thickness in Regions of Pressure Gradient and Flow Through the Surface

Description: Note presenting a theoretical investigation of the effect of an increase in boundary-layer thickness on the stability of the boundary layer. The analysis also includes an investigation of the effect of an increase in boundary-layer thickness on the roughness Reynolds number and of the ability of blowing at the stagnation point to increase the boundary-layer thickness without making the boundary layer unstable.
Date: August 1952
Creator: Tetervin, Neal & Levine, David A.
Partner: UNT Libraries Government Documents Department
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Theoretical study of the transonic lift of a double-wedge profile with detached bow wave

Description: Report presenting a theoretical study of the aerodynamic characteristics at small angle of attack of a thin, double-wedge profile in the range of supersonic flight speed in which the bow wave is detached. The calculations provide, for extremely small angles of attack, the following information as a function of the transonic similarity parameter: chordwise lift distribution, lift-curve slope, and position of center of lift.
Date: December 1952
Creator: Vincenti, Walter G. & Wagoner, Cleo B.
Partner: UNT Libraries Government Documents Department
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Fatigue strengths of aircraft materials : axial-load fatigue tests on notched sheet specimens of 24S-T3 and 75S-T6 aluminum alloys and of SAE 4130 steel with stress-concentration factor of 1.5

Description: Report presenting results of axial-load fatigue tests on notched specimens of three sheet materials: 24S-T3 and 75S-T6 aluminum alloys and normalized SAE 4130 steel. Tests were run at four levels of nominal mean stress.
Date: February 1952
Creator: Grover, H. J.; Hyler, W. S. & Jackson, L. R.
Partner: UNT Libraries Government Documents Department
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Stability of Laminar Boundary Layer Near a Stagnation Point Over an Impermeable Wall and a Wall Cooled by Normal Fluid Injection

Description: Note presenting a theoretical determination of minimum critical Reynolds numbers for laminar instability of two-dimensional stagnation flows over a wall cooled by normal fluid injection. The individual and net effects of wall temperature and normal fluid injection on the stability characteristics of the laminar boundary layer are investigated.
Date: August 1957
Creator: Morduchow, Morris; Grape, Richard G. & Shaw, Richard P.
Partner: UNT Libraries Government Documents Department
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Simplified Method for Estimating Compressible Laminar Heat Transfer With Pressure Gradient

Description: "In the present report an approximation is made in the method of Technical Note 3326, which simplifies the calculation of heat transfer. Good agreement with the method of Technical Note 3326 is expected for isothermal surfaces with adverse and small favorable pressure gradients regardless of surface temperature and also for flow with large favorable pressure gradient over highly cooled surfaces" (p. 1).
Date: December 1956
Creator: Reshotko, Eli
Partner: UNT Libraries Government Documents Department
open access

Flow surfaces in rotating axial-flow passages

Description: Report presenting an investigation of three-dimensional, incompressible, nonviscous, absolute irrotational fluid motion is determined for flow through rotating axial-flow passages bounded by straight blades of finite spacing and infinite axial length lying on meridional planes. Solutions are obtained for five passages with varying blade spacing and hub-tip ratio. The results are presented in such a manner as to apply for all ratios of axial velocity to passage tip speed.
Date: November 1952
Creator: Stanitz, John D. & Ellis, Gaylord O.
Partner: UNT Libraries Government Documents Department
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The response of an airplane to random atmospheric disturbances

Description: The statistical approach to the gust-load problem which consists in considering flight through turbulent air to be a stationary random process is extended by including the effect of lateral variation of the instantaneous gust intensity on the aerodynamic forces. The forces obtained in this manner are used in dynamic analyses of rigid and flexible airplanes free to move vertically, in pitch, and in roll. The effect of the interaction of longitudinal, vertical, and lateral gusts on the wing stresses is also considered.
Date: April 1957
Creator: Diederich, Franklin W.
Partner: UNT Libraries Government Documents Department
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Inviscid Flow About Airfoils at High Supersonic Speeds

Description: Report presenting an investigation of steady flow about curved airfoils at high supersonic speeds. Testing demonstrated that within the limitation of the assumption of ideal gas flow, the shock-expansion method may be used with good accuracy to predict pressure distributions on curved airfoils at arbitrarily high Mach numbers.
Date: March 1952
Creator: Eggers, A. J., Jr. & Syvertson, Clarence A.
Partner: UNT Libraries Government Documents Department
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Laminar Boundary Layer on Cone in Supersonic Flow at Large Angle of Attack

Description: Note presenting an analysis of the laminar boundary-layer flow about a circular cone at large angles of attack to a supersonic stream in the plane of symmetry by a method applicable in general to the flow about conical bodies. Velocity profiles at the bottom of the cone indicated that the expected tendency of the boundary layer to become thinner on the under side of the cone as the angle of attack is increased.
Date: November 1952
Creator: Moore, Franklin K.
Partner: UNT Libraries Government Documents Department
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Oblique-Shock Relations at Hypersonic Speeds for Air in Chemical Equilibrium

Description: Note presenting oblique-shock relations for air in chemical equilibrium, which have been calculated for flight velocities up to 25,000 feet per second at altitudes up to 200,000 feet. The variation of flow-deflection angle with shock angle differs significantly from that of an ideal gas. Results regarding normal-velocity ratio, flow deflection across shock, Mach number behind shock, mass-flow ratio, temperature, entropy increase, and other parameters are provided.
Date: January 1957
Creator: Moeckel, W. E.
Partner: UNT Libraries Government Documents Department
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Study of Vortex Shedding as Related to Self-Excited Torsional Oscillations of an Airfoil

Description: Note presenting the results of the experimental investigation of the self-excited torsional oscillation of an NACA 0006 airfoil suspended elastically. The relationship between the torsional oscillation and the shedding of vortices was investigated for this airfoil. Two types of oscillation phenomena were found: one was exhibited by cases with angles of attack just above stall and one was exhibited by cases with higher angles of attack.
Date: September 1951
Creator: Chuan, Raymond L. & Magnus, Richard J.
Partner: UNT Libraries Government Documents Department
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Comparison of two- and three-dimensional potential-flow solutions in a rotating impeller passage

Description: Report presenting a solution for three-dimensional, incompressible, non-viscous, potential flow in a rotating impeller passage with zero through flow. The solution is obtained for a conventional impeller with straight blades but with the inducer vanes removed and the impeller blades extended upstream parallel to the axis of the impeller.
Date: October 1952
Creator: Ellis, Gaylord O. & Stanitz, John D.
Partner: UNT Libraries Government Documents Department
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Preview of Behavior of Grain Boundaries in Creep of Aluminum Bicrystals

Description: Note presenting testing of the gliding of one metal crystal with respect to another, along their mutual grain boundary, during high-temperature creep tests conducted with bicrystals of pure aluminum. Stresses of from 1 to 100 psi and temperatures from 200 to 650 degrees Celsius were employed. Results regarding grain boundary glide rate, influence of orientation difference between grains, influence of temperature, influence of applied stress, structure of the operated grain boundary, and structural changes within grains are provided.
Date: July 1952
Creator: Rhines, F. N. & Cochardt, A. W.
Partner: UNT Libraries Government Documents Department
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Incomplete time response to a unit impulse and its application to lightly damped linear systems

Description: Report presenting a study of the use of the incomplete time response to a unit impulse as a device to analyze lightly damped linear systems. The incomplete time response to a unit impulse computed from an incomplete time response and complete input adequately describes a light damped linear system without requiring an estimate and correction.
Date: December 1956
Creator: Donegan, James J. & Huss, Carl R.
Partner: UNT Libraries Government Documents Department
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Wind-tunnel investigation of an external-flow jet-augmented slotted flap suitable for application to airplanes with pod-mounted jet engines

Description: Report presenting a wind-tunnel investigation to determine the characteristics of an external-flow jet-augmented slotted flap which appears suitable for applications to pod-mounted jet engines. The investigation included tests of an unswept wing and of a model of a swept-wing jet transport or bomber. Results regarding the unswept wings, swept wings, longitudinal stability and trim, and estimated take-off and landing performance are provided.
Date: December 1956
Creator: Campbell, John P. & Johnson, Joseph L., Jr.
Partner: UNT Libraries Government Documents Department
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The calculation of pressure on slender airplanes in subsonic and supersonic flow

Description: "Under the assumption that a wing, body, or wing-body combination is slender or flying at near sonic velocity, expressions are given which permit the calculation of pressure in the immediate vicinity of the configuration. The disturbance field, in both subsonic and supersonic flight, is shown to consist of two-dimensional disturbance fields extending laterally and a longitudinal field that depends on the streamwise growth of cross-sectional area. A discussion is also given of couplings, between lifting and thickness effects, that necessarily arise as a result of the quadratic dependence of pressure on the induced velocity components" (author).
Date: March 1953
Creator: Heaslet, Max A. & Lomax, Harvard
Partner: UNT Libraries Government Documents Department
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Theoretical Calculations of Supersonic Wave Drag at Zero Lift for a Particular Store Arrangement

Description: "An analysis, based on the linearized thin-airfoil theory for supersonic speeds, of the wave drag at zero lift has been carried out for a simple two-body arrangement consisting of two wedgelike surfaces, each with a rhombic lateral cross section and emanating from a common apex. Such an arrangement could be used as two stores, either embedded within or mounted below a wing, or as auxiliary bodies wherein the upper halves could be used as stores and the lower halves for bomb or missile purposes. The complete range of supersonic Mach numbers has been considered and it was found that by orienting the axes of the bodies relative to each other a given volume may be redistributed in a manner which enables the wave drag to be reduced within the lower supersonic speed range (where the leading edge is substantially subsonic)" (p. 1).
Date: January 1958
Creator: Margolis, Kenneth; Malvestuto, Frank S., Jr. & Maxie, Peter J., Jr.
Partner: UNT Libraries Government Documents Department
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Vibration survey of four representative types of air-cooled turbine blades

Description: Report presenting an investigation conducted in a turbojet engine mounted in a sea-level test stand to determine the vibrational characteristics of four representative types of air-cooled turbine blades.Two were standard-span blades and two were long-span blades for high mass-flow turbines. Results regarding the coolant-flow rate, vibratory stresses, vibrational characteristics, and failures are provided.
Date: July 1958
Creator: Calvert, Howard F. & Smith, Gordon T.
Partner: UNT Libraries Government Documents Department
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The planing characteristics of a surface having a basic angle of dead rise of 40 degrees and horizontal chine flare

Description: Report presenting an experimental investigation with a surface with a dead rise angle of 40 degrees and horizontal chine flare to determine the effects of increasing the angle of dead rise on the planing characteristics of horizontally flared prismatic surfaces. Wetted length, resistance, center-of-pressure location, and draft were determined for a range of speed coefficients and trims. Planing characteristics for a given trim were found to depend mainly on lift coefficient.
Date: December 1952
Creator: Blanchard, Ulysse J.
Partner: UNT Libraries Government Documents Department
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Theory and apparatus for measurement of emissivity for radiative cooling of hypersonic aircraft with data for Inconel and Inconel X

Description: The importance of radiation as a means of cooling high-supersonic- and hypersonic-speed aircraft is discussed to show the need for measurements of the total hemispherical emissivity of surfaces. The theory underlying the measurement of the total hemispherical emissivity of surfaces is presented, readily duplicable apparatus for performing the measurements is described, and measurements for stably oxidized Inconel and Inconel X are given for the temperature range from 600 F to 2,000 F.
Date: October 1957
Creator: O'Sullivan, William J., Jr. & Wade, William R.
Partner: UNT Libraries Government Documents Department
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A Theoretical and Experimental Investigation of the Effects of Yaw on Pressures, Forces, and Moments During Seaplane Landings and Planing

Description: A theory for the side force, rolling moment, yawing moment, and pressure distribution during yawed landings and planing of seaplanes was developed. For the special case of the straight-sided wedge without chine immersion, the results of the theoretical analysis are presented in the form of generalized curves covering all step landing conditions. Experimental impact and planing data are presented for a prismatic wedge having an angle of dead rise of 22.5 degrees and are shown to be in reasonable agreement with the theoretical predictions.
Date: November 1952
Creator: Smiley, Robert F.
Partner: UNT Libraries Government Documents Department
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