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Preliminary Investigation of Effects of Alpha-Particle Bombardment on the Creep Rate of Aluminum

Description: Memorandum presenting a preliminary investigation to determine the effects of alpha-particle bombardment on the creep rate of aluminum wire at 400 degrees Fahrenheit. The alpha radiation from an 85-millicurie polonium source appeared to decrease slightly the creep rate of the aluminum.
Date: July 3, 1947
Creator: Kittel, J. Howard
Partner: UNT Libraries Government Documents Department

Preliminary Correlation of the Effect of Compressibility on the Location of the Section Aerodynamic Center at Subcritical Speeds

Description: Memorandum presenting a correlation of available two-dimensional airfoil data to determine the effects of compressibility on the location of the section aerodynamic center at low lift coefficients. The results indicate that large forward or rearward movements of the aerodynamic center with Mach number are possible.
Date: November 3, 1948
Creator: Polhamus, Edward C.
Partner: UNT Libraries Government Documents Department

Computed Performance of a Composite Engine Based on Experimental Data for a Single-Cylinder Conventional Aircraft Engine Converted to Compression-Ignition Operation

Description: Memorandum presenting a determination of the performance of a single-cylinder spark-ignition engine modified to operate on a compression-ignition cycle with a compression ratio of 8.0. Experimental data were obtained at an inlet-manifold pressure of 100 inches of mercury absolute, fuel-air ratios of 0.040 and 0.025, and engine exhaust pressures of 30 to 100 inches of mercury absolute. Results regarding single-cylinder-engine experimental data and full-scale-engine calculations are provided.
Date: February 3, 1947
Creator: McCoy, J. Arnold & Szel, Frank
Partner: UNT Libraries Government Documents Department

Knock-limited power outputs from a CFR engine using internal coolants 3: four alkyl amines, three alkanolamines six amides, and eight heterocyclic compounds

Description: Report presenting investigations to determine the antiknock effectiveness of various additive-water solutions used as internal coolants in conjunction with AN-F-28, Amendment-2, fuel in a modified CFR engine.
Date: February 3, 1947
Creator: Imming, Harry S. & Bellman, Donald R.
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics at subsonic and supersonic Mach numbers of a thin triangular wing of aspect ratio 2 2: maximum thickness at midchord

Description: "The lift, drag, and pitching-moment characteristics of a triangular wing, having an aspect ratio of 2 and a symmetrical double-wedge profile of 5-percent-chord maximum thickness at midchord, have been evaluated from wind-tunnel tests at Mach numbers from 0.50 to 0.975 and from 1.09 to 1.49 and at Reynolds numbers ranging from 0.67 to 0.85 million. The lift, drag, and pitching-moment coefficients of the triangular wing with a leading-edge sweepback of approximately 63 degrees did not exhibit the irregular variations with Mach number at high subsonic and low supersonic Mach numbers that are characteristic of unswept wings. The lift-curve slope increased steadily with Mach number below unity and declined slowly beyond the Mach number of 1.13" (p. 1).
Date: December 3, 1948
Creator: Walker, Harold J. & Berggren, Robert E.
Partner: UNT Libraries Government Documents Department

Preliminary Evaluation of the Spin and Recovery Characteristics of the Douglas XF3D-1 Airplane

Description: "A preliminary evaluation of the spin and recovery characteristics of the XF3D-1 airplane has been made, based primarily on the results of the free-spinning tunnel tests of a model which closely simulated the XF3D-1 in tail design, tail length, and mass loading. Estimates have been made of the rudder-pedal force that may be encountered in effecting recovery from a spin and of the spin recovery parachute requirements of the airplane for demonstration spins. The method of bail-out which should be used if it becomes necessary for the crew to abandon the airplane during a spin is indicated" (p. 1).
Date: July 3, 1947
Creator: Scher, Stanley H.
Partner: UNT Libraries Government Documents Department

A flight investigation and analysis of the lateral-oscillation characteristics of an airplane

Description: Report presenting flight tests to determine the causes of undesirable dynamic lateral-stability characteristics of an airplane. Various rudder modifications were flight tested with the rudder free and fixed over an indicated airspeed range from approximately 200 to 450 miles per hour. Results regarding rudder-fixed characteristics and rudder-free characteristics are provided.
Date: June 3, 1948
Creator: Stough, Carl J. & Kauffman, William M.
Partner: UNT Libraries Government Documents Department

The effect of air-jet and strip modifications on the hydrodynamic characteristics of the streamline fuselage of a transonic airplane

Description: Report presenting 1/12-size model of a streamline fuselage modified by patterns of air jets or strips on the fuselage bottom. The effects of spacing of jets, length of jet rows, and direction of jets were determined for a simulated chine configuration. Data are presented on resistance, trim, effective hydrodynamic lift, and spray.
Date: June 3, 1949
Creator: Weinflash, Bernard; Christopher, Kenneth W. & Shuford, Charles L., Jr.
Partner: UNT Libraries Government Documents Department

Experimental investigation of the effects of viscosity on the drag of bodies of revolution at a Mach number 1.5

Description: Report presenting testing to determine the effects of viscosity on the drag and base pressure characteristics of various bodies of revolution at a Mach number of 1.5. The models were tested with smooth surfaces and roughness to evaluate the effects of Reynolds number for both laminar and turbulent boundary layers. Results regarding the reduction of data, precision, effects of support interference, Schileren photographs, and theoretical calculations are provided.
Date: April 3, 1947
Creator: Chapman, Dean R. & Perkins, Edward W.
Partner: UNT Libraries Government Documents Department

Vibration of loosely mounted turbine blades during service operation of a turbojet engine with centrifugal compressor and straight-flow combustion chambers

Description: Report presenting an experimental investigation to determine the vibration characteristics of loosely mounted turbine blades during service operation of a turbojet engine. High-temperature strain gages were used to measure turbine-blade vibrations. Results regarding oscillograph records, critical speeds and frequencies, vibratory-stress levels, and effect of tightening the blade mount are provided.
Date: November 3, 1949
Creator: Morgan, W. C.; Kemp, R. H. & Manson, S. S.
Partner: UNT Libraries Government Documents Department

Carbon deposition of 19 fuels in an annular turbojet combustor

Description: Report presenting the effects of fuel properties and change in simulated engine operating conditions on carbon deposition in an annular turbojet combustor. The fuel properties examined included specific gravity, volumetric average boiling temperature, hydrocarbon type, and hydrogen-carbon weight ratio. The fuels included hydrocarbons of the paraffinic, olefinic, and aromatic types as well as fuel mixtures.
Date: February 3, 1949
Creator: Wear, Jerrold D. & Jonash, Edmund R.
Partner: UNT Libraries Government Documents Department

Analytical determination of effect of water injection on power output of turbine-propeller engine

Description: From Introduction: "Water injection at the compressor inlet has been successfully used to increase the thrust of turbojet engines. References 1 and 2 indicate that the sea-level static thrust of a centrifugal-flow-type turbojet engine may be increased about 25 percent by use of liquid injection. Reference 3 indicates that greater thrust augmentation is possible at a compressor pressure ratio of 11 than of 4."
Date: November 3, 1949
Creator: Ross, Albert O. & Huppert, Merle C.
Partner: UNT Libraries Government Documents Department

Investigation of interaction effects arising from side-wall boundary layers in supersonic wind-tunnel tests of airfoils

Description: Report presenting an investigation to determine the cause for a discrepancy between theoretical and experimental pressure distributions found during a two-dimensional investigation of flapped airfoils in a 2- by 8-inch supersonic tunnel. The results indicated that a tunnel-boundary-layer and model-flow interaction effect on the flow over models mounted directly from the walls in supersonic wind tunnels exists.
Date: November 3, 1948
Creator: Czarnecki, K. R. & Schueller, C. F.
Partner: UNT Libraries Government Documents Department

Flight Investigation of the Knock-Limited Performance of a Triptane Blend, a Toluene Blend, and 28-R Fuel in an R-1830-75 Engine

Description: "Knock-limited performance data were obtained for three fuels on an R-1830-75 engine in a B-24D airplane at engine speeds of 1800, 2250, and 2600 rpm, a spark advance of 25 degrees B.T.C., and carburetor-air temperatures of 85 F for 1800 and 2250 rpm and 100 F for 2600 rpm. The test fuels were a blend of 80 percent 28-R plus 20 percent triptane (leaded to 4.5 ml TEL/gal), a blend of 80 percent 28-R plus 15 percent toluene (leaded to 4.5 ml TEL / gal), and 28-R fuel. The knock-limited manifold pressure of the toluene blend depreciated more in the lean region than the triptane blend or 28-R fuel" (p. 1).
Date: September 3, 1946
Creator: Blackman, Calvin C.
Partner: UNT Libraries Government Documents Department

Ground Effect on Downwash Angles and Wake Location

Description: "A theoretical study was made of the reduction in downwash and the upward displacement of the wake in the presence of the ground, and some verification of theory was obtained by means of air-flow measurements made with a ground-board and image-wing combination. Methods are given for estimating the effects and numerous examples are included to illustrate the nature of these effects and to show their order of magnitude" (p. 1).
Date: October 3, 1941
Creator: Katzoff, S. & Sweberg, Harold H.
Partner: UNT Libraries Government Documents Department

Determination of Ram-Jet Combustion-Chamber Temperatures by Means of Total-Pressure Surveys

Description: "A method is described by which the total temperature of the gases at the combustion-chamber outlet of a ram-jet engine may be determined from the loss in total pressure measured across the combustion chamber. A working chart is presented by means of which the ratio of the total temperature of the gases at the combustion-chamber outlet to the total temperature of the gases at the combustion-chamber inlet may be determined from the measured loss of total pressure across the combustion chamber and the known values of air flow, total pressure, and total temperature at the combustion-chamber inlet. Values of total-temperature ratio across the combustion chamber of a 20-inch ram jet were obtained in the Cleveland altitude wind tunnel over a range of pressure altitudes from 6000 to 15,000 feet" (p. 1).
Date: March 3, 1947
Creator: Pinkel, I. Irving
Partner: UNT Libraries Government Documents Department

Performance of J33-A-21 and J33-A-23 Turbojet-Engine Compressors with Water Injection

Description: "As part of the performance investigation of compressors for the J33 turbojet engine, the A-21 model and the A-23 model with a 17- and a 34-blade impeller were operated with water injection at their respective design equivalent speeds of 11,500 and 11,750 rpm. Inlet conditions of pressure of 14 inches of mercury absolute and of ambient temperature correspond to those of the investigation of these models without water injection. The water-air ratio by weight ranged from 0.05 to 0.06. By the use of water injection, the peak pressure ratio of the A-21 compressor and the A-23 compressor with a 34-blade impeller increased approximately 0.38, whereas that of the A-23 compressor with a 17-blade impeller increased only 0.14" (p. 1).
Date: August 3, 1949
Creator: Beede, William L. & Withee, Joseph R., Jr.
Partner: UNT Libraries Government Documents Department

Altitude-Wind-Tunnel Investigation of a 4000-Pound-Thrust Axial-Flow Turbojet Engine, Part 1, Performance and Windmilling Drag Characteristics

Description: From Summary: "The results of altitude-wind-tunnel tests conducted to determine the performance of an axial-flow-type 4000-pound-thrust turbojet engine for a range of pressure altitudes from 5000 to 40,000 feet and ram pressure ratios from 1.02 to 1.86 are presented and the experimental and analytical methods employed are discussed. By means of suitable generalizing factors applied to the measured performance data, curves were obtained from which the engine performance at any altitude for a given ram pressure ratio can be estimated. The data presented include the windmilling drag characteristics of the turbojet engine for the ranges of altitudes and ram pressure ratios covered by the performance data."
Date: August 3, 1948
Creator: Fleming, William A.
Partner: UNT Libraries Government Documents Department

Vibrational modes of several hollow turbine blades and of solid turbine blade of similar aerodynamic design

Description: Experimental study to determine the vibrational modes of several hollow turbine blades and a solid turbine blade of similar aerodynamic design. Results regarding the significance of nodal patterns, vibrational modes of six blade types, and the probability of excitation in some of the blades are provided.
Date: October 3, 1949
Creator: Kemp, R. H. & Shifman, J.
Partner: UNT Libraries Government Documents Department

Effect of fuel on performance of a single combustor of an I-16 turbojet engine at simulated altitude conditions

Description: As part of a study of the effects of fuel composition on the combustor performance of a turbojet engine, an investigation was made in a single I-16 combustor with the standard I-16 injection nozzle, supplied by the engine manufacturer, at simulated altitude conditions. The 10 fuels investigated included hydrocarbons of the paraffin olefin, naphthene, and aromatic classes having a boiling range from 113 degrees to 655 degrees F. They were hot-acid octane, diisobutylene, methylcyclohexane, benzene, xylene, 62-octane gasoline, kerosene, solvent 2, and Diesel fuel oil. The fuels were tested at combustor conditions simulating I-16 turbojet operation at an altitude of 45,000 feet and at a rotor speed of 12,200 rpm. At these conditions the combustor-inlet air temperature, static pressure, and velocity were 60 degrees F., 12.3 inches of mercury absolute, and 112 feet per second respectively, and were held approximately constant for the investigation. The reproducibility of the data is shown by check runs taken each day during the investigation. The combustion in the exhaust elbow was visually observed for each fuel investigated.
Date: July 3, 1947
Creator: Zettle, Eugene V.; Bolz, Ray E. & Dittrich, R. T.
Partner: UNT Libraries Government Documents Department

Preliminary investigation of cone-type diffusers designed for minimum spillage at inlet

Description: Report presenting a preliminary investigation of cone-type diffusers designed for minimum spillage at the inlet during operation in the supersonic tunnel at Mach number 1.85. Pressure recoveries of a series of stationary cones with included angles from 20 degrees to 60 degrees were investigated. Results regarding the pressure recovery with stationary cones and pressure recovery of movable-cone configurations are provided.
Date: May 3, 1948
Creator: Luidens, Roger W. & Hunczak, Henry
Partner: UNT Libraries Government Documents Department

Pressure Distributions Over a Wing-Fuselage Model at Mach Numbers of 0.4 to 0.99 and at 1.2

Description: Report presenting pressure distributions over a prolate spheroid of fineness ratio 6 and over a combination of this body with an NACA 65-010 wing section for a range of Mach numbers. Results regarding wall and sting interference, nature of flow over a model in the transonic region, development of supersonic flow from subsonic flow, and a comparison of experimental and theoretical flow at subsonic stream Mach numbers are provided.
Date: November 3, 1948
Creator: Matthews, Clarence W.
Partner: UNT Libraries Government Documents Department

The Effect of Mach Number on the Aerodynamic Characteristics of a Single-Engine Pursuit Airplane as Determined From Tests of a 1/3-Scale Model

Description: Report discussing the effects of Mach number on the aerodynamic characteristics of an Allison powered single-engine pursuit airplane. Information about the lift, drag, pitching-moment characteristics, stability, tail effectiveness, and elevator effectiveness with Mach number is provided.
Date: May 3, 1945
Creator: Robinson, Robert C. & Jessen, Henry
Partner: UNT Libraries Government Documents Department

Endurance Tests of a 22-Inch-Diameter Pulse-Jet Engine With a Neoprene-Coated Valve Grid

Description: Report discussing the results of testing to determine the operating life of a 22-inch-diameter pulse-jet engine equipped with a neoprene-coated valve grid. The valve grid was found to extend the operating life and only reduced the performance slightly.
Date: October 3, 1945
Creator: Manganiello, Eugene J.; Valerino, Michael F. & Breisch, John H.
Partner: UNT Libraries Government Documents Department