Pressure recovery at supersonic speeds through annular duct inlets situated in a region of appreciable boundary layer 1: addition of energy to the boundary layer (open access)

Pressure recovery at supersonic speeds through annular duct inlets situated in a region of appreciable boundary layer 1: addition of energy to the boundary layer

Report presenting a model with a nozzle upstream of an annular duct inlet for the purpose of ejecting high-velocity air into the boundary layer of the flow along the forebody tested between Mach numbers of 1.36 and 2.01. Results wind-tunnel data, equivalent pressure recovery, and scale effects are provided.
Date: April 1, 1948
Creator: Davis, Wallace F. & Brajnikoff, George B.
System: The UNT Digital Library
Preliminary investigation of the altitude performance of pentaborane and a pentaborane : JP-4 blend in an experimental 9.5-inch-diameter tubular combustor (open access)

Preliminary investigation of the altitude performance of pentaborane and a pentaborane : JP-4 blend in an experimental 9.5-inch-diameter tubular combustor

From Summary: "A preliminary investigation was conducted to determine the altitude performance of pentaborane and a blend fuel of 64.2 percent pentaborane in JP-4 fuel in a tubular combustor of a current production type turbojet engine. Deposits on the liner barrel and dome were virtually nonexistent. The combustion efficiency of 90 to 94 percent for pentaborane and approximately 90 percent for the blend. Outlet temperature profiles were marginal; however, the developed combustor provided lower pressure losses than obtained in conventional combustors."
Date: April 1, 1957
Creator: Kaufman, Warner B. & Branstetter, J. Robert
System: The UNT Digital Library
Wind-tunnel investigation of the aerodynamic characteristics in pitch of wing-fuselage combinations at high subsonic speeds: Aspect-ratio series (open access)

Wind-tunnel investigation of the aerodynamic characteristics in pitch of wing-fuselage combinations at high subsonic speeds: Aspect-ratio series

Report presenting an investigation in the 7- by 10-foot tunnel to determine the effect of aspect ratio on the aerodynamic characteristics in pitch of wing-fuselage combinations with 45 degrees sweepback at the quarter-chord line and 0.6 taper ratio at high subsonic speeds. Results regarding the lift characteristics, pitching-moment characteristics, drag characteristics, and lift-drag ratios are provided.
Date: April 1, 1952
Creator: Kuhn, Richard E. & Wiggins, James W.
System: The UNT Digital Library
Pressure Distributions at Mach Numbers From 0.6 to 1.9 Measured in Free Flight on a Parabolic Body of Revolution With Sharply Convergent Afterbody (open access)

Pressure Distributions at Mach Numbers From 0.6 to 1.9 Measured in Free Flight on a Parabolic Body of Revolution With Sharply Convergent Afterbody

Report reporting measurements of pressure distributions obtained in a flight test of a fin-stabilized parabolic body of revolution with a sharply convergent afterbody. Pressures were measured at eight longitudinal stations on the body and over a range of Mach numbers. Results regarding basic data, the effect of sting, the variation of pressure coefficient with Mach number, pressure distributions, velocity distribution and discussion of flow phenomena, and drag are presented.
Date: April 1, 1952
Creator: Stoney, William E., Jr.
System: The UNT Digital Library
Investigation at high subsonic speeds of finned and unfinned bodies mounted at various locations from the wings of unswept- and swept-wing--fuselage models, including measurements of body loads (open access)

Investigation at high subsonic speeds of finned and unfinned bodies mounted at various locations from the wings of unswept- and swept-wing--fuselage models, including measurements of body loads

Report presenting an investigation to determine the effects of location of bodies (finned and unfinned) on the aerodynamic characteristics of unswept- and swept-wing--fuselage models and to determine the aerodynamic loads on the bodies in the presence of the wings. Results for the complete model characteristics and for the body are provided.
Date: April 1, 1954
Creator: Alford, William J., Jr. & Silvers, H. Norman
System: The UNT Digital Library
Starting and performance characteristics of a large asymmetric supersonic free-jet facility (open access)

Starting and performance characteristics of a large asymmetric supersonic free-jet facility

Report presenting the characteristics of an asymmetric free-jet facility constructed to investigate a 48-inch-diameter ramjet engine and the associated asymmetric supersonic inlet and inlet diffuser. The design flow Mach number of 2.755 could not be established in the free-jet facility with dry inlet air at a temperature of 528 degrees Fahrenheit and overall pressure ratios up to 11.
Date: April 1, 1954
Creator: Seashore, Ferris L. & Hurrell, Herbert G.
System: The UNT Digital Library
A transonic wind-tunnel investigation of the effects of twist and camber with and without incidence, twist and body indentation on the aerodynamic characteristics of a 45 degree sweptback wing-body configuration (open access)

A transonic wind-tunnel investigation of the effects of twist and camber with and without incidence, twist and body indentation on the aerodynamic characteristics of a 45 degree sweptback wing-body configuration

Report presenting a transonic wind-tunnel investigation of several sweptback wing-body configurations to determine the effects of twist and camber with incidence, the separate effects of twist without camber, and the influence of body indentation on the effects of twist and camber, and twist alone.
Date: April 1, 1954
Creator: Cooper, J. Lawrence
System: The UNT Digital Library
Adaptation of Combustion Principles to Aircraft Propulsion, Volume 1, Basic Considerations in the Combustion of Hydrocarbon Fuels with Air (open access)

Adaptation of Combustion Principles to Aircraft Propulsion, Volume 1, Basic Considerations in the Combustion of Hydrocarbon Fuels with Air

The report summarizes source material on combustion for flight-propulsion engineers. First, several chapters review fundamental processes such as fuel-air mixture preparation, gas flow and mixing, flammability and ignition, flame propagation in both homogenous and heterogenous media, flame stabilization, combustion oscillations, and smoke and carbon formation. The practical significance and the relation of these processes to theory are presented. A second series of chapters describes the observed performance and design problems of engine combustors of the principal types. An attempt is made to interpret performance in terms of the fundamental processes and theories previously reviewed. Third, the design of high-speed combustion systems is discussed. Combustor design principles that can be established from basic considerations and from experience with actual combustors are described. Finally, future requirements for aircraft engine combustion systems are examined.
Date: April 1, 1955
Creator: Barnett, Henry C. & Hibbard, Robert R.
System: The UNT Digital Library
The Use of Area Suction to Increase the Effectiveness of a Trailing-Edge Flap on a Triangular Wing of Aspect Ratio 2 (open access)

The Use of Area Suction to Increase the Effectiveness of a Trailing-Edge Flap on a Triangular Wing of Aspect Ratio 2

"A wind-tunnel investigation was conducted to determine the effect of applying area-suction boundary-layer control to a constant-chord plain flap on a triangular wing of aspect ratio 2. The results showed that with small amounts of suction applied near the leading edge of the flap, high lift at relatively low attitudes can be obtained" (p. 1). The typical lift, drag, pitching-moment data, effects of the porous area, effects of suction, and comparison of theoretical and experimental flap lift are described.
Date: April 1, 1954
Creator: Kelly, Mark W. & Tolhurst, William H., Jr.
System: The UNT Digital Library
Survey of supersonic inlets for high Mach number applications (open access)

Survey of supersonic inlets for high Mach number applications

Report presenting an assessment of various inlet design philosophies assessed on the basis of recent experimental results at Mach numbers up to 5. The basic compression systems are compared for Mach 4.0 turbojet and hypersonic-cruise ramjet engines.The best-suited inlet for the Mach 4.0 turbojet engine is the combined external-plus-internal compression.
Date: April 1, 1958
Creator: Connors, James F. & Allen, John L.
System: The UNT Digital Library
Measurement of Static Pressure on Aircraft (open access)

Measurement of Static Pressure on Aircraft

"Existing data on the errors involved in the measurement of static pressure by means of static-pressure tubes and fuselage vents are presented. The errors associated with the various design features of static-pressure tubes are discussed for the condition of zero angle of attack and for the case where the tube is included to the flow. Errors due to variations in the configuration of static-pressure vents are also presented" (p. 1).
Date: April 1, 1957
Creator: Gracey, William
System: The UNT Digital Library
Evaluation of Several Ram-Jet Combustor Configurations Using Pentaborane Fuel (open access)

Evaluation of Several Ram-Jet Combustor Configurations Using Pentaborane Fuel

Report presenting an investigation of several combustor configurations to determine if the length of the engine could be reduced. Testing indicated that when using a highly reactive fuel in the low subsonic region of the diffuser, part of the engine length can be eliminated.
Date: April 1, 1957
Creator: Sheldon, John W. & Cervenka, A. J.
System: The UNT Digital Library
Dilution of liquid oxygen when nitrogen is used for pressurization (open access)

Dilution of liquid oxygen when nitrogen is used for pressurization

Report presenting a graphic method for determining the composition and phases within a propellant tank when liquid oxygen is pressurized with nitrogen gas and some of the calculations involved. The assumed limiting conditions are that pressurizing gas flows adiabatically from the pressure tank and that equilibrium exists in the oxygen-nitrogen system. The experiment indicates that a series dilution of the oxidant occurs when nitrogen is used as a pressurizing gas, but a barrier at the liquid-gas interface would permit the use of nitrogen.
Date: April 1, 1958
Creator: Walsh, Thomas J.; Hibbard, R. R. & Ordin, Paul M.
System: The UNT Digital Library
The adhesion of molten boron oxide to various materials (open access)

The adhesion of molten boron oxide to various materials

This report includes the description and results of an experiment evaluating the amount of adhesion existing between the liquid boron oxide and various materials used in engines.
Date: April 1, 1958
Creator: Witzke, W. R.
System: The UNT Digital Library
Nitrited-Steel Piston Rings for Engines of High Specific Power (open access)

Nitrited-Steel Piston Rings for Engines of High Specific Power

"Several designs of nitrided-steel piston rings were performance-tested under variable conditions of output. The necessity of good surface finish and conformity of the ring to the bore was indicated in the preliminary tests. Nitrided-steel rings of the same dimensions as cast-iron rings operating on the original piston were unsatisfactory, and the final design was a lighter, rectangular, thin-face-width ring used on a piston having a maximum cross-head area and a revised skirt shape. Results were obtained from single-cylinder and multicylinder engine runs" (p. 1).
Date: April 1, 1944
Creator: Collins, John H., Jr.; Bisson, Edmond E. & Schmiedlin, Ralph F.
System: The UNT Digital Library
Velocity distributions on two-dimensional wing-duct inlets by conformal mapping (open access)

Velocity distributions on two-dimensional wing-duct inlets by conformal mapping

The conformal-mapping method of the Cartesian mapping function is applied to the determination of the velocity distribution on arbitrary two-dimensional duct-inlet shapes such as are used in wing installations. An idealized form of the actual wing-duct inlet is analyzed. The effects of leading edge stagger, inlet-velocity ratio, and section lift coefficients on the velocity distribution are included in the analysis. Numerical examples are given and, in part, compared with experimental data.
Date: April 1, 1947
Creator: Perl, W. & Moses, H. E.
System: The UNT Digital Library
Analysis of wind-tunnel stability and control tests in terms of flying qualities of full-scale airplanes (open access)

Analysis of wind-tunnel stability and control tests in terms of flying qualities of full-scale airplanes

From Introduction: "The purpose of this paper is to outline a suggested form of presentation of the results of a stability and control investigation in terms of flying qualities as defined in reference 1 and to systematize and review briefly the analytical work required for this type of presentation. No effort is made to specify definite test procedures."
Date: April 1, 1943
Creator: Kayten, Gerald G.
System: The UNT Digital Library
Frequency Response of Linear Systems From Transient Data (open access)

Frequency Response of Linear Systems From Transient Data

"Methods are presented that use general correlative time-response input and output data for a linear system to determine the frequency-response function of that system. These methods give an exact description of any linear system for which such transient data are available. Examples are shown of application of a method to both an underdamped and a critically damped exact second-order system, and to an exact first-order system with and without dead time. Experimental data for a turbine-propeller engine showing the response of engine speed to change in propeller-blade angle are presented and analyzed" (p. 547).
Date: April 1, 1949
Creator: LaVerne, Melvin E. & Boksenbom, Aaron S.
System: The UNT Digital Library
Tank investigation of the hydrodynamic characteristics of a 1/13.33-scale jet-powered dynamic model of the Martin XP6M-1 flying boat: TED No. NACA DE 385 (open access)

Tank investigation of the hydrodynamic characteristics of a 1/13.33-scale jet-powered dynamic model of the Martin XP6M-1 flying boat: TED No. NACA DE 385

A tank investigation was made of the hydrodynamic characteristics of a 1/13.33-scale jet-powered dynamic model of the 160,000-pound Martin XP6M-1 flying boat. Longitudinal stability during take-off and landing, resistance of the complete model, spray characteristics, flap loads, and effect of sinking speed in smooth and rough water are presented, as well as behavior during taxiing, take-off and landing in rough water. The effect on spray of two bows and several bow-spray-strip modifications and the effect on resistance of afterbody chine strips also are presented.
Date: April 1, 1955
Creator: Carter, Arthur W. & Blanchard, Ulysse J.
System: The UNT Digital Library
Combustion in the Wake as a Means of Body-Drag Reduction as Determined from Free-Flight Tests of 40-Millimeter Shells (open access)

Combustion in the Wake as a Means of Body-Drag Reduction as Determined from Free-Flight Tests of 40-Millimeter Shells

"The results of free-flight drag tests of 40-millimeter shells conducted by the National Advisory Committee for Aeronautics for the Ballistic Research Laboratories, Ordnance Department, U. S. Army, are presented. A drag reduction at supersonic speeds of approximately 20 percent of the projectile's drag was obtained by combustion in the wake of the projectile in flight" (p. 1).
Date: April 1, 1953
Creator: Welsh, Clement J.
System: The UNT Digital Library
An empirically derived method for calculating pressure distribution at supercritical Mach numbers and moderate angles of attack (open access)

An empirically derived method for calculating pressure distribution at supercritical Mach numbers and moderate angles of attack

Report presenting a procedure for calculating pressure distributions over airfoils at supercritical Mach numbers. Only the forward portion of the airfoil, where interaction between local boundary-layer thickness and local-pressure distribution is negligible, is considered in detail. The method cannot be considered definitive because it requires that certain characteristics regarding pressure distributions and geometric properties be known.
Date: April 1, 1947
Creator: Nitzberg, Gerald E. & Sluder, Loma E.
System: The UNT Digital Library
Survey of Supersonic Inlets for High Mach Number Applications (open access)

Survey of Supersonic Inlets for High Mach Number Applications

Report discussing various inlet design philosophies based on the results of testing at Mach numbers up to 5. The most ideal inlet design was found to be one with combined external-plus-internal compression due to problems noted with both external-only and internal-only inlets.
Date: April 1, 1958
Creator: Connors, James F. & Allen, John L.
System: The UNT Digital Library
Wind-Tunnel Measurement of Static Forces on Internally Carried Bombs of Two Different Bluff Shapes in the Flow Field of a Swept-Wing Fighter-Bomber Configuration at a Mach Number of 1.6 (open access)

Wind-Tunnel Measurement of Static Forces on Internally Carried Bombs of Two Different Bluff Shapes in the Flow Field of a Swept-Wing Fighter-Bomber Configuration at a Mach Number of 1.6

Report discussing the influence of forces and moments on a fighter-bomber airplane with an open bomb bay and on two bluff bomb shapes in various positions below the fuselage and plane of symmetry. The wing was found to have a noticeable effect on bomb forces and that bluff bombs affect the longitudinal characteristics of the wing-fuselage combination.
Date: April 1, 1957
Creator: Geier, Douglas J. & Robins, A. Warner
System: The UNT Digital Library