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An analysis of once-per-revolution oscillating aerodynamic thrust loads on single-rotation propellers on tractor airplanes at zero yaw

Description: A simplified procedure is shown for calculating the once-per-revolution oscillating aerodynamic thrust loads on propellers of tractor airplanes at zero yaw. The only flow field information required for the application of the procedure is a knowledge of the upflow angles at the horizontal center line of the propeller disk. Methods are presented whereby these angles may be computed without recourse to experimental survey of the flow field. The loads computed by the simplified procedure are compar… more
Date: March 21, 1955
Creator: Rogallo, Vernon L.; Yaggy, Paul F. & McCloud, John L., III
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Linearized Lifting-Surface and Lifting-Line Evaluations of Sidewash Behind Rolling Triangular Wings at Supersonic Speeds

Description: "The lifting-surface sidewash behind rolling triangular wings has been derived for a range of supersonic Mach numbers for which the wing leading edges remain swept behind the mark cone emanating from the wing apex. Variations of the sidewash with longitudinal distance in the vertical plane of symmetry are presented in graphical form. An approximate expression for the sidewash has been developed by means of an approach using a horseshoe-vortex approximate-lifting-line theory" (p. 455).
Date: October 21, 1955
Creator: Bobbitt, Percy J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Two-dimensional compressible flow in centrifugal compressors with straight blades

Description: "Six numerical examples are presented for steady, two-dimensional, compressible, nonviscous flow in centrifugal compressors with thin straight blades, the center lines of which generate the surface of a right circular cone when rotated about the axis of the compressor. A seventh example is presented for incompressible flow. The solutions were obtained in a region of the compressors, including the impeller tip, that was considered to be unaffected by the diffuser vanes or by the impeller-inlet c… more
Date: June 21, 1949
Creator: Stanitz, John D. & Ellis, Gaylord O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Investigation with an interferometer of the turbulent mixing of a free supersonic jet

Description: The free turbulent mixing of a supersonic jet of Mach number 1.6 has been experimentally investigated. An interferometer, of which a description is given, was used for the investigation. Density and velocity distributions through the mixing zone have been obtained. It was found that there was similarity in distribution at the cross sections investigated and that, in the subsonic portion of the mixing zone, the velocity distribution fitted the theoretical distribution for incompressible flow. It… more
Date: January 21, 1949
Creator: Gooderum, Paul B.; Wood, George P. & Brevoort, Maurice J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Application of the Analogy Between Water Flow With a Free Surface and Two-Dimensional Compressible Gas Flow

Description: "The theory of the hydraulic analogy -- that is, the analogy between water flow with a free surface and two-dimensional compressible gas flow -- and the limitations and conditions of the analogy are discussed. A test was run using the hydraulic analogy as applied to the flow about circular cylinders of various diameters at subsonic velocities extending into the supercritical range. The apparatus and techniques used in this application are described and criticized" (p. 311).
Date: August 21, 1946
Creator: Orlin, W. James; Lindner, Norman J. & Bitterly, Jack G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Effect of combustor-inlet conditions on performance of an annular turbojet combustor

Description: From Summary: "The combustion performance, and particularly the phenomenon of altitude operational limits, was studied by operating the annular combustor of a turbojet engine over a range of conditions of air flow, inlet pressure, inlet temperature, and fuel flow. Information was obtained on the combustion efficiencies, the effect on combustion of inlet variables, the altitude operational limits with two different fuels, the pressure losses in the combustor, the temperature and velocity profile… more
Date: March 21, 1947
Creator: Childs, J. Howard; McCafferty, Richard J. & Surine, Oakley W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Analysis of Heat and Compressibility Effects in Internal Flow Systems and High-Speed Tests of a Ram-Jet System

Description: Report discussing an analysis has been made by the NACA of the effects of heat and compressibility in the flow through the internal systems of aircraft along with equations and charts are developed whereby the flow characteristics at key stations in a typical internal system may be readily obtained.
Date: July 21, 1942
Creator: Becker, John V. & Baals, Donald D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Effects of wing flexibility and variable air lift upon wing bending moment during landing impacts of a small seaplane

Description: From Summary: "A smooth-water-landing investigation was conducted with a small seaplane to obtain experimental wing-bending-moment time histories together with time histories of the various parameters necessary for the prediction of wing bending moments during hydrodynamic forcing functions. The experimental results were compared with calculated results which include inertia-load effects and the effects of air-load variation during impact. The responses of the fundamental mode were calculated w… more
Date: December 21, 1949
Creator: Merten, Kenneth F. & Beck, Edgar B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Flight investigation of the effect of various vertical-tail modifications on the directional stability and control characteristics of a propeller-driven fighter airplane

Description: "A flight investigation was made to determine the effect of various vertical-tail modifications and of some combinations of these modifications on the directional stability and control characteristics of a propeller-driven fighter airplane. Six different vertical-tail configurations were investigated to determine the lateral-directional oscillation characteristics, the sideslip characteristics, the yaw due to ailerons in rudder-fixed rolls from turns and pull-outs, the trim changes due to speed… more
Date: November 21, 1946
Creator: Johnson, Harold I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

On Stability of Free Laminar Boundary Layer Between Parallel Streams

Description: "An analysis and calculations on the stability of the free laminar boundary layer between parallel streams were made for an incompressible fluid using the Tollmien-Schlichting theory of small disturbances. Because the boundary conditions are at infinity, two solutions of the Orr-Sommerfeld stability equations need not be considered, and the remaining two solutions are exponential in character at the infinite boundaries. The calculations show that the flow is unstable except for very low Reynold… more
Date: March 21, 1949
Creator: Lessen, Martin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Some Effects of Bluntness on Boundary-Layer Transition and Heat Transfer at Supersonic Speeds

Description: "Large downstream movements of transition observed when the leading edge of a hollow cylinder or a flat plate is slightly blunted are explained in terms of the reduction in Reynolds number at the outer edge of the boundary layer due to the detached shock wave. The magnitude of this reduction is computed for cones and wedges for Mach numbers to 20. Concurrent changes in outer-edge Mach number and temperature occur in the direction that would increase the stability of the laminar boundary layer. … more
Date: November 21, 1955
Creator: Moeckel, W. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Investigation of the Laminar Aerodynamic Heat-Transfer Characteristics of a Hemisphere-Cylinder in the Langley 11-inch Hypersonic Tunnel at a Mach Number of 6.8

Description: "A program to investigate the aerodynamic heat transfer of a nonisothermal hemisphere-cylinder has been conducted in the Langley 11-inch hypersonic tunnel at a Mach number of 6.8 and a Reynolds number from approximately 0.14 x 10(6) to 1.06 x 10(6) based on diameter and free-stream conditions. The experimental heat-transfer coefficients were slightly less over the whole body than those predicted by the theory of Stine and Wanlass (NACA technical note 3344) for an isothermal surface. For station… more
Date: March 21, 1956
Creator: Crawford, Davis H. & McCauley, William D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Tests in the variable-density wind tunnel of the NACA 23012 airfoil with plain and split flaps

Description: From Summary: "Section characteristics for use in wing design are presented for the NACA 23012 airfoil with plain and split flaps of 20 percent wing chord at a value of the effective Reynolds number of about 8,000,000. The flap deflections covered a range from 60 degrees upward to 75 degrees downward for the plain flap and from neutral to 90 degrees downward for the split flap. The split flap was aerodynamically superior to the plain flap in producing high maximum lift coefficients and in havin… more
Date: January 21, 1938
Creator: Abbott, Ira H. & Greenberg, Harry
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Span load distribution for tapered wings with partial-span flaps

Description: Tables are given for determining the load distribution of tapered wings with partial-span flaps placed either at the center or at the wing tips. Seventy-two wing-flap combinations, including two aspect ratios, four taper ratios, and nine flap lengths, are included. The distributions for the flapped wing are divided into two parts, one a zero lift distribution due primarily to the flaps and the other an additional lift distribution due to an angle of attack of the wing as a whole. Comparison bet… more
Date: November 21, 1936
Creator: Pearson, H. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Wing-nacelle-propeller interference for wings of various spans force and pressure-distribution tests

Description: Report presents the results of an experimental investigation made in the NACA full-scale wind tunnel to determine the effect of wing span on nacelle-propeller characteristics and, reciprocally, the lateral extent of nacelle and propeller influence on a monoplane wing. The results provide a check on the validity of the previous research on nacelles and propellers with 15-foot-span wings tested in the 20-foot wind tunnel and reported in technical reports 415, 462, 505, 506, and 507.
Date: April 21, 1936
Creator: Robinson, Russell G. & Herrnstein, William H., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The drag of airplane wheels, wheel fairings, and landing gears 2: nonretractable and partly retractable landing gears

Description: This is the second report giving the results obtained in the NACA 20-foot wind tunnel on the drag due to landing gears. The present report gives the results of tests of nonretractable and partly retractable landing gears intended for heavier low-wing monoplanes of the transport and bomber type.
Date: June 21, 1934
Creator: Biermann, David & Herrnstein, William H., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Spinning characteristics of wings 1: rectangular Clark Y monoplane wing

Description: "A series of wind tunnel tests of a rectangular Clark Y wing was made with the NACA spinning balance as part of a general program of research on airplane spinning. All six components of the aerodynamic force and moment were measured throughout the range of angles of attack, angles of sideslip, and values omega b/2v likely to be attained by a spinning airplane; the results were reduced to coefficient form. It is concluded that a conventional monoplane with a rectangular Clark y wing can be made … more
Date: November 21, 1934
Creator: Bamber, M. J. & Zimmerman, C. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The drag of airplane wheels, wheel fairings, and landing gears - 3

Description: The tests reported in this report conclude the investigation of landing-gear drag that has been carried out in the NACA 20-foot wind tunnel. They supplement earlier tests (reported in Technical Report No. 485) made with full-scale dummy wheels, wheel fairings, and landing gears intended for airplanes of 3,000 pounds gross weight and include tests of tail wheels and tail skids.
Date: November 21, 1934
Creator: Herrnstein, William H., Jr. & Biermann, David
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Large-scale aerodynamic characteristics of airfoils as tested in the variable density wind tunnel

Description: From Summary: "In order to give the large-scale characteristics of a variety of airfoils in a form which will be of maximum value, both for airplane design and for the study of airfoil characteristics, a collection has been made of the results of airfoil tests made at full-scale values of the Reynolds number in the variable density wind tunnel of the National Advisory Committee for Aeronautics. They have been corrected for tunnel wall interference and are presented not only in the conventional … more
Date: October 21, 1929
Creator: Jacobs, Eastman N. & Anderson, Raymond F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Combustion in a High-Speed Compression-Ignition Engine

Description: "An investigation conducted to determine the factors which control the combustion in a high-speed compression-ignition engine is presented. Indicator cards were taken with the Farnboro indicator and analyzed according to the tangent method devised by Schweitzer. The analysis show that in a quiescent combustion chamber increasing the time lag of auto-ignition increases the maximum rate of combustion. Increasing the maximum rate of combustion increases the tendency for detonation to occur" (p. 63… more
Date: May 21, 1931
Creator: Rothrock, A. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Pressure Distribution Over a Thick, Tapered and Twisted Monoplane Wing Model-N.A.C.A. 81-J

Description: "This reports presents the results of pressure distribution tests on a thick, tapered and twisted monoplane wing model. The investigation was conducted for the purpose of obtaining data on the aerodynamic characteristics of the new wing and to provide additional information suitable for use in the design of tapered cantilever wings. The tests included angles of attack up to 90 degrees. The span loading over the wing was approximately of elliptical shape, which gave rise to relatively small bend… more
Date: May 21, 1930
Creator: Wenzinger, Carl J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Measurement of aerodynamic forces for various mean angles of attack on an airfoil oscillating in pitch and on two finite-span wings oscillating in bending with emphasis on damping in the stall

Description: "The oscillating air forces on a two-dimensional wing oscillating in pitch about the midchord have been measured at various mean angles of attack and at Mach numbers of 0.35 and 0.7. The magnitudes of normal-force and pitching-moment coefficients were much higher at high angles of attack than at low angles of attack for some conditions. Large regions of negative damping in pitch were found, and it was shown that the effect of increasing the Mach number 0.35 to 0.7 was to decrease the initial an… more
Date: January 21, 1956
Creator: Rainey, A. Gerald
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Impingement of water droplets on wedges and double-wedge airfoils at supersonic speeds

Description: "An analytical solution has been obtained for the equations of motion of water droplets impinging on a wedge in a two-dimensional supersonic flow field with a shock wave attached to the wedge. The closed-form solution yields analytical expressions for the equation of the droplet trajectory, the local rate of impingement and the impingement velocity at any point on the wedge surface, and the total rate of impingement. The analytical expressions are utilized to determine the impingement on the fo… more
Date: April 21, 1953
Creator: Serafini, John S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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