Effect of Inlet-Guide-Vane Angle on Blade Vibration and Rotating Stall of 13-Stage Axial-Flow Compressor in Turbojet Engine (open access)

Effect of Inlet-Guide-Vane Angle on Blade Vibration and Rotating Stall of 13-Stage Axial-Flow Compressor in Turbojet Engine

Report presenting a blade-vibration and rotating-stall survey on a modified version of a production turbojet engine with a 13-stage axial-flow compressor with a design pressure ratio of 7 and an air flow of 120 pounds per second. This testing was carried out due to the problems rotating stall can cause with both experimental and production axial-flow compressors. Results regarding the rotating-stall patterns, rotor-blade vibrations, radial and axial strength of rotating stall, and maximum rotating-stall speed are provided.
Date: May 22, 1956
Creator: Calvert, Howard F.; Medeiros, Arthur A. & Johnson, Donald F.
System: The UNT Digital Library
Propagation of a free flame in a turbulent gas stream (open access)

Propagation of a free flame in a turbulent gas stream

Effective flame speeds of free turbulent flames were measured by photographic, ionization-gap, and photomultiplier-tube methods, and were found to have a statistical distribution attributed to the nature of the turbulent field. The effective turbulent flame speeds for the free flame were less than those previously measured for flames stabilized on nozzle burners, Bunsen burners, and bluff bodies. The statistical spread of the effective turbulent flame speeds was markedly wider in the lean and rich fuel-air-ratio regions, which might be attributed to the greater sensitivity of laminar flame speed to flame temperature in those regions. Values calculated from the turbulent free-flame-speed analysis proposed by Tucker apparently form upper limits for the statistical spread of free-flame-speed data. Hot-wire anemometer measurements of the longitudinal velocity fluctuation intensity and longitudinal correlation coefficient were made and were employed in the comparison of data and in the theoretical calculation of turbulent flame speed.
Date: May 7, 1956
Creator: Mickelsen, William R. & Ernstein, Norman E.
System: The UNT Digital Library
A special method for finding body distortions that reduce the wave drag of wing and body combinations at supersonic speeds (open access)

A special method for finding body distortions that reduce the wave drag of wing and body combinations at supersonic speeds

For a given wing and supersonic Mach number, the problem of shaping an adjoining fuselage so that the combination will have a low wave drag is considered. Only fuselages that can be simulated by singularities (multipoles) distributed along the body axis are studied. However, the optimum variations of such singularities are completely specified in terms of the given wing geometry. An application is made to an elliptic wing having a biconvex section, a thickness-chord ratio equal to 0.05 at the root, and an aspect ratio equal to 3. A comparison of the theoretical results with a wind-tunnel experiment is also presented.
Date: May 16, 1956
Creator: Lomax, Harvard & Heaslet, Max A.
System: The UNT Digital Library
A Summary of Results Obtained During Flight Simulation of Several Aircraft Prototypes With Variable-Stability Airplanes (open access)

A Summary of Results Obtained During Flight Simulation of Several Aircraft Prototypes With Variable-Stability Airplanes

Memorandum describing an investigation using two airplanes, an F6F-3 and F-86A, each fitted with servo equipment for varying in flight the lateral and directional stability and handling characteristics, which have been flown by test pilots to simulate the predicted dynamic behavior of six prototype airplanes. The methods of simulation and the types and ranges of variables considered are presented and the results of the individual programs are discussed.
Date: May 25, 1956
Creator: McNeill, Walter E. & Creer, Brent Y.
System: The UNT Digital Library
Investigation of the possibility of simplifying missile guidance systems by the use of free-floating flaps and spring-mounted control surfaces (open access)

Investigation of the possibility of simplifying missile guidance systems by the use of free-floating flaps and spring-mounted control surfaces

Report presenting an investigation of the use of aerodynamic and mechanical devices for improving the response of guided missiles. An analysis indicates that the use of free-floating flaps and spring-mounted control surfaces should be able to increase maneuverability to the point that electronic automatic stabilization and gain-adjusting devices can be eliminated.
Date: May 17, 1956
Creator: Hikido, Katsumi; Hayashi, Paul H. & Lessing, Henry C.
System: The UNT Digital Library
On the Range of Applicability of the Transonic Area Rule (open access)

On the Range of Applicability of the Transonic Area Rule

"Some insight into the range of applicability of the transonic area rule has been gained by comparison with the appropriate similarity rule of transonic flow theory and with available experimental data for a large family of rectangular wings having NACA 63AXXX profieles. In spite of the small number of geometric variables available for such a family, the range is sufficient that cases both compatible and incompatible with the area rule are included" (p. 1).
Date: May 1956
Creator: Spreiter, John R.
System: The UNT Digital Library
Comparison of the experimental and theoretical distributions of lift on a slender inclined body of revolution at M = 2 (open access)

Comparison of the experimental and theoretical distributions of lift on a slender inclined body of revolution at M = 2

Report presenting pressure distributions and force characteristics for a body of revolution consisting of a fineness ratio of 5.75, circular-arc, ogival nose tangent to a cylindrical afterbody for a range of angles of attack. Comparison of the theoretical and experimental pressure distributions shows that for zero lift, both slender-body theory and higher-order theories yield results that are in good agreement with theory.
Date: May 1956
Creator: Perkins, Edward W. & Kuehn, Donald M.
System: The UNT Digital Library
Comparison of experimental and theoretical normal-force distributions (including Reynolds number effects) on an ogive-cylinder body at Mach number 1.98 (open access)

Comparison of experimental and theoretical normal-force distributions (including Reynolds number effects) on an ogive-cylinder body at Mach number 1.98

Effects of Reynolds number and angle of attack on the pressure distribution and normal-force characteristics of a body of revolution consisting of a fineness ratio 3 ogival nose tangent to a cylindrical afterbody 7 diameters long have been determined. The test Mach number was 1.98 and the angle-of-attack range from 0 degree to 20 degrees. The Reynolds numbers, based on body diameter, were 0.15 x 10(6) and 0.45 x 10(6). The experimental results are compared with theory.
Date: May 1956
Creator: Perkins, Edward W. & Jorgensen, Leland H.
System: The UNT Digital Library
Investigation of boundary-layer transition on 10 degree cone in langley 4- by 4-foot supersonic pressure tunnel at Mach numbers of 1.41, 1.61, and 2.01 (open access)

Investigation of boundary-layer transition on 10 degree cone in langley 4- by 4-foot supersonic pressure tunnel at Mach numbers of 1.41, 1.61, and 2.01

Report presenting an investigation to determine the transition Reynolds numbers on a 10 degree cone in the 4- by 4-foot supersonic pressure tunnel at three Mach numbers and a range of Reynolds numbers. Results regarding a smooth cone and a cone with roughness are provided.
Date: May 1956
Creator: Sinclair, Archibald R. & Czarnecki, K. R.
System: The UNT Digital Library
Boundary Layer Behind Shock or Thin Expansion Wave Moving Into Stationary Fluid (open access)

Boundary Layer Behind Shock or Thin Expansion Wave Moving Into Stationary Fluid

Note presenting a determination of the boundary layer behind a shock or thin expansion wave advancing into a stationary fluid. The assumption of a thin expansion wave was found to be valid for weak expansions but becomes progressively less accurate for strong expansion waves. The turbulent-boundary-layer solutions in this report represent an extension of empirical, semi-infinite flat-plate, boundary-layer data to the case where the wall is moving.
Date: May 1956
Creator: Mirels, Harold
System: The UNT Digital Library
A sonic-flow orifice probe for the in-flight measurements of temperature profiles of a jet engine exhaust with afterburning (open access)

A sonic-flow orifice probe for the in-flight measurements of temperature profiles of a jet engine exhaust with afterburning

Report presenting a description of a temperature-measuring system using two sonic-flow orifices in series, which is used to measure the exhaust gas temperature of an afterburning jet engine mounted in a swinging pitot-static probe. It was found to improve the reliability and reduce the computational time required of the previously used system.
Date: May 1956
Creator: Havill, C. Dewey & Rolls, L. Stewart
System: The UNT Digital Library
Preliminary investigation of the effectiveness of a sliding flap in deflecting a propeller slipstream downward for vertical take-off (open access)

Preliminary investigation of the effectiveness of a sliding flap in deflecting a propeller slipstream downward for vertical take-off

An investigation of the effectiveness of a wing equipped with a sliding flap and a leading-edge slat in deflecting a propeller slipstream downward for vertical take-off was conducted in a static-thrust facility. Results regarding the characteristics with leading-edge slat and with extended flap chord are provided.
Date: May 1956
Creator: Kuhn, Richard E. & Spreemann, Kenneth P.
System: The UNT Digital Library
Comparison between experimental and predicted downwash at a Mach number of 0.25 behind a wing-body combination having a triangular wing of aspect ratio of 2.0 (open access)

Comparison between experimental and predicted downwash at a Mach number of 0.25 behind a wing-body combination having a triangular wing of aspect ratio of 2.0

A study to evaluate a method for predicting the downwash in a transverse plane behind a wing-body combination throughout a range of angles of attack. The wing-body combination had a ratio of maximum body diameter to wing span of 0.259, a triangular wing with an aspect ratio of 2.0, and a body of revolution with a fineness ratio of 12.5. Results regarding span loading, downwash, and vortex cores are provided.
Date: May 1956
Creator: Sorensen, Norman E. & Hopkins, Edward J.
System: The UNT Digital Library
Static longitudinal and lateral stability characteristics at low speed of unswept-midwing models having wings with an aspect ratio of 2, 4, or 6 (open access)

Static longitudinal and lateral stability characteristics at low speed of unswept-midwing models having wings with an aspect ratio of 2, 4, or 6

Report presenting an investigation to determine the effects of the various components and combinations of components on the static longitudinal and lateral stability characteristics of unswept-midwing models having wings with a variety of aspect ratios for a range of angles of attack. Results regarding static longitudinal stability characteristics and static lateral stability characteristics are provided.
Date: May 1956
Creator: Wolhart, Walter D. & Thomas, David F., Jr.
System: The UNT Digital Library
Investigation at zero forward speed of a leading-edge slat as a longitudinal control device for vertically rising airplanes that utilize the redirected-slipstream principle (open access)

Investigation at zero forward speed of a leading-edge slat as a longitudinal control device for vertically rising airplanes that utilize the redirected-slipstream principle

Report presenting an investigation of a leading-edge slat as a possible longitudinal control device for vertically rising airplanes that utilize the redirected-slipstream principle at zero forward speed in a static-thrust facility. A semispan wing model equipped with large-chord slotted flaps and two large-diameter overlapping propellers was used. Results regarding the effect of slat position, effect of propeller position, characteristics of the modified model, and a comparison of characteristics with one or two propellers are provided.
Date: May 1956
Creator: Kuhn, Richard E.
System: The UNT Digital Library
Longitudinal Aerodynamic Characteristics of Various Configurations of a Revised 1/22-Scale Model of the Republic F-105 Airplane at Mach Numbers of 1.41 and 2.01 (open access)

Longitudinal Aerodynamic Characteristics of Various Configurations of a Revised 1/22-Scale Model of the Republic F-105 Airplane at Mach Numbers of 1.41 and 2.01

Report presenting an investigation of a model of the Republic F-105 airplane to determine the static longitudinal aerodynamic characteristics of a revised configuration. The revisions included a lengthened fuselage, a relocated canopy, a contoured fuselage afterbody, a ventral fin, and an enlarged vertical tail. Results regarding the effect of stores, effect of dive-brake flaps, effect of forebody modifications, gun blisters, and duct air bleed, and a comparison of the modified model with the original are provided.
Date: May 4, 1956
Creator: Foster, Gerald V.
System: The UNT Digital Library
Some Transonic Aerodynamic Characteristics of a Model Similar to the McDonnell F3H-2N Airplane (open access)

Some Transonic Aerodynamic Characteristics of a Model Similar to the McDonnell F3H-2N Airplane

Report discussing testing of a model of the McDonnell F3H-2N to determine its pitch-up and buffet boundaries and its longitudinal stability and control data obtainable with the pulse-tail technique. Stability was found to be less at low trim angles of attack than at high trim angles of attack up to a point. The buffet boundary was not obtainable through this testing.
Date: May 15, 1956
Creator: Crabill, Norman L. & Jackson, Bruce G.
System: The UNT Digital Library
Investigation of Afterburner Combustion Screech and Methods of Its Control at High Combustor Pressure Levels (open access)

Investigation of Afterburner Combustion Screech and Methods of Its Control at High Combustor Pressure Levels

Memorandum presenting an experimental investigation of various methods for the control of afterburner combustion screech at afterburner-inlet total pressures from 4000 to 6400 pounds per square foot absolute. Generally, the range of afterburner fuel-air ratios in which screech occurred and the intensity of screech did not vary appreciably in the range of pressures covered.
Date: May 14, 1956
Creator: Trout, Arthur M.; Koffel, William K. & Smolak, George R.
System: The UNT Digital Library
Influence of Large Amplitudes on Flexural Motions of Elastic Plates (open access)

Influence of Large Amplitudes on Flexural Motions of Elastic Plates

Note presenting a nonlinear plate theory of motion, valid for large deflections, in the light of the three-dimensional theory and other nonlinear plate theories. The nonlinear equations are solved for the case of propagation of straight-crested waves and the wave velocities are computed for various values of the parameters involved.
Date: May 1956
Creator: Herrmann, George
System: The UNT Digital Library
Effect of combustion-chamber pressure and nozzle expansion ratio on theoretical performance of several rocket propellant systems (open access)

Effect of combustion-chamber pressure and nozzle expansion ratio on theoretical performance of several rocket propellant systems

Theoretical calculations of specific impulse to determine the separate effects of increasing the combustion-chamber pressure and the nozzle expansion ratio on the performance of the propellants, hydrogen-fluorine, hydrogen-oxygen, ammonia-fluorine and AN-F-58 fuel - white fuming nitric acid (95 percent). The results indicate that an increase in specific impulse obtainable with an increase in combustion-chamber pressure is almost entirely caused by the increased expansion ratio through the nozzle.
Date: May 25, 1956
Creator: Morrell, Virginia E.
System: The UNT Digital Library
Approximate indicial lift functions for several wings of finite span in incompressible flow as obtained from oscillatory lift coefficients (open access)

Approximate indicial lift functions for several wings of finite span in incompressible flow as obtained from oscillatory lift coefficients

Report presenting the unsteady-lift functions for a wing undergoing a sudden change in sinking speed for delta wings with three aspect ratios and rectangular and elliptical wings with three aspect ratios. Results regarding the delta-plan-form K1 function, indical spanwise loading distributions, effect of plan-form shape on the K1 function, and effect of aspect ratio on the K1 and K2 functions are provided.
Date: May 1956
Creator: Drischler, Joseph A.
System: The UNT Digital Library
Wind-Tunnel Investigation of a Number of Total-Pressure Tubes at High Angles of Attack: Subsonic, Transonic, and Supersonic Speeds (open access)

Wind-Tunnel Investigation of a Number of Total-Pressure Tubes at High Angles of Attack: Subsonic, Transonic, and Supersonic Speeds

Note presenting the effect of inclination of the airstream on the measured pressures of 54 total-pressure tubes for angles of attack up to 60 degrees and over a Mach number range from 0.26 to 1.62. The investigation was conducted in five wind tunnels. Results regarding effect of impact-opening size, effect of varying the shape of the internal chamber, effect of external shape, effect of slant profile, effect of venting of shielded tubes, effect of varying the probe position and the throat diameter of shielded tubes, effect of slant profile on shielded tubes, effect of the shape of the entry of shielded tubes, effect of Mach number on nonshielded tubes, and effect of Mach number on shielded tubes are provided.
Date: May 1956
Creator: Gracey, William
System: The UNT Digital Library
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 (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

Report presenting measurements of the oscillating air forces on a two-dimensional wing oscillating in pitch about the midchord that have been measured at various mean angles of attack and at two different Mach numbers. The magnitudes of normal-force and pitching-moment coefficients were found to be much higher at large angles of attack than at low angles of attack for some conditions. Results regarding the effects at low angles of attack, high angles of attack, and a description of finite-span wings oscillating in first bending mode are provided.
Date: May 1956
Creator: Rainey, A. Gerald
System: The UNT Digital Library
Investigation of the compressive strength and creep lifetime of 2024-T aluminum-alloy skin-stringer panels at elevated temperatures (open access)

Investigation of the compressive strength and creep lifetime of 2024-T aluminum-alloy skin-stringer panels at elevated temperatures

Report presenting the experimental results of an investigation to determine compressive strength and creep lifetime of 2024-T aluminum-alloy skin-stringer panels at room temperature and 400 degrees Fahrenheit. A method which makes use of time-dependent compressive stress-strain curves for predicting creep lifetime of panels is presented.
Date: May 1956
Creator: Mathauser, Eldon E. & Deveikis, William D.
System: The UNT Digital Library