Tables and charts of flow parameters across oblique shocks (open access)

Tables and charts of flow parameters across oblique shocks

Shock-wave equations have been evaluated for a range of Mach number in front of the shock from 1.05 to 4.0. Mach number behind the shock, pressure ratio, derivation of flow, and angle of shock are presented on charts. Values are also included for density ratio and change in entropy.
Date: August 1948
Creator: Neice, Mary M.
System: The UNT Digital Library
Axial fatigue tests at zero mean stress of 24S-T and 75S-T aluminum-alloy strips with a central circular hole (open access)

Axial fatigue tests at zero mean stress of 24S-T and 75S-T aluminum-alloy strips with a central circular hole

From Summary: "Axial fatigue tests at zero mean stress have been made on 0.032- and 0.064-inch 24S-T and 0.032-inch 75S-T sheet-metal specimens 1/4, 1/2, 1, and 2 inches wide without a hole and with central holes giving a range of hole diameter D to specimen width W from 0.01 to 0.95. No systematic difference was noted between the results for the 0.032-inch and the 0.064-inch specimens although the latter seemed the more consistent. In general the fatigue strength based on the minimum section dropped sharply as the ration D/W was increased from zero to about 0.25. The plain specimens showed quite a pronounced decrease in fatigue strength with increasing width. The holed specimens showed only slight and rather inconclusive evidence of this size effect. The fatigue stress-concentration factor was higher for 75S-T than for 24S-T alloy. Evidence was found that a very small hole would not cause any reduction in fatigue strength."
Date: August 1948
Creator: Brueggeman, W. C. & Mayer, M., Jr.
System: The UNT Digital Library
Analysis of parameters for thrust control of a turbojet engine equipped with air-inlet throttle and variable-area exhaust nozzle (open access)

Analysis of parameters for thrust control of a turbojet engine equipped with air-inlet throttle and variable-area exhaust nozzle

From Introduction: "In this report, altitude, airplane velocity, exhaust-nozzle area, and turbine-inlet temperature were chosen and corresponding engine speed, fuel flow, and throttle pressure ratio were found. A detailed discussion of the engine analysis and the calculations used are presented in Appendix A. The derivations of the principal equations used are presented in appendix B."
Date: August 10, 1948
Creator: Boksenbom, Aaron S. & Feder, Melvin S.
System: The UNT Digital Library
Preliminary results of natural icing of an axial-flow turbojet engine (open access)

Preliminary results of natural icing of an axial-flow turbojet engine

Report presenting a flight investigation in natural icing conditions to determine the effect of ice formations on the performance of an axial-flow turbojet engine. Results regarding the tail-pipe temperature, engine jet thrust, and characteristics of ice formation are provided. No general conclusions can be reached from the data because the icing condition was relatively light.
Date: August 6, 1948
Creator: Acker, Loren W.
System: The UNT Digital Library
Low-Speed Investigation of a Small Triangular Wing of Aspect Ratio 2.0 3: Static Stability With Twin Vertical Fins (open access)

Low-Speed Investigation of a Small Triangular Wing of Aspect Ratio 2.0 3: Static Stability With Twin Vertical Fins

"Low-speed wind-tunnel tests were made of a triangular wing with two arrangements of twin vertical fins. With these twin fins mounted either symmetrically or wholly above the wing chord plane, approximately constant effectiveness in proportion to the fin size was obtained throughout the angle-of-attack range. The addition of these fins, however, resulted in a decrease in maximum lift and a reduction in static longitudinal stability at lift coefficients above 0.4" (p. 1).
Date: August 24, 1948
Creator: Rose, Leonard M.
System: The UNT Digital Library
Investigation of the I-40 jet-propulsion engine in the Cleveland altitude wind tunnel 1: performance and windmilling drag characteristics (open access)

Investigation of the I-40 jet-propulsion engine in the Cleveland altitude wind tunnel 1: performance and windmilling drag characteristics

Report presenting the performance characteristics of the I-40 jet propulsion engine and an analysis for a range of altitudes and ram pressure ratios. Results regarding the component efficiencies, engine performance, generalizing factors, and windmilling drag characteristics are provided.
Date: August 24, 1948
Creator: Gendler, Stanley L. & Koffel, William K.
System: The UNT Digital Library
Investigation of the I-40 Jet-Propulsion Engine in the Cleveland Altitude Wind Tunnel 1: Performance and Windmilling Drag Characteristics (open access)

Investigation of the I-40 Jet-Propulsion Engine in the Cleveland Altitude Wind Tunnel 1: Performance and Windmilling Drag Characteristics

Report presenting the performance characteristics of the I-40 jet-propulsion engine for a range of altitudes and ram pressure ratios. Results regarding component efficiencies, engine performance, generalizing factors, and windmilling drag characteristics are provided.
Date: August 24, 1948
Creator: Gendler, Stanley L. & Koffel, William K.
System: The UNT Digital Library
A limit pressure coefficient and an estimation of limit forces on airfoils at supersonic speeds (open access)

A limit pressure coefficient and an estimation of limit forces on airfoils at supersonic speeds

Report presenting the results of an estimation of the limit forces on airfoils at supersonic speeds. The limit pressure coefficient attainable on an airfoil is shown to be about 70 percent of the pressure coefficient for a vacuum over a wide range of Mach numbers.
Date: August 23, 1948
Creator: Mayer, John P.
System: The UNT Digital Library
Application of one part of Von Karman's two-dimensional transonic similarity law to drag data of NACA 65-series wings (open access)

Application of one part of Von Karman's two-dimensional transonic similarity law to drag data of NACA 65-series wings

Report presenting the use of Von Karman's two-dimensional transonic similarity law as applied to drag data of three different thickness wings with NACA 65-series sections and aspect ratios of 7.6 over a range of Mach numbers. The correlation was found to be satisfactory, with results better in the subsonic range than in the supersonic range.
Date: August 24, 1948
Creator: Amer, Kenneth B.
System: The UNT Digital Library
Operating Temperatures of I-40-5 Turbojet Engine Burner Liners and the Effect of Temperature Variation on Burner-Liner Service Life (open access)

Operating Temperatures of I-40-5 Turbojet Engine Burner Liners and the Effect of Temperature Variation on Burner-Liner Service Life

Report presenting an investigation of burner liners in a turbojet engine to determine the principal factors limiting the burner-liner service life. The investigation covered a range of engine speeds and testing was conducted to determine whether bare, ceramic-coated, or shielded thermocouples would give the most correct temperature readings.
Date: August 23, 1948
Creator: Wilsted, H. D.; Duffy, Robert T. & Grey, Ralph E.
System: The UNT Digital Library
Measurements of the chordwise pressure distributions over the wing of the XS-1 research airplane in flight (open access)

Measurements of the chordwise pressure distributions over the wing of the XS-1 research airplane in flight

Report presenting measurements of the chordwise pressure distributions over the 8-percent-thick wing of the XS-1 research airplane at a section near the midspan of the left wing. Data are presented for a Mach number range and a normal-force coefficient of about 0.33. Results regarding the upper-surface pressure distribution, lower-surface pressure distributions, and total section loads are provided.
Date: August 4, 1948
Creator: Beeler, De E.; McLaughlin, Milton D. & Clift, Dorothy C.
System: The UNT Digital Library
Design and Performance of Experimental Axial-Discharge Mixed-Flow Compressor 1: Impeller Design Theory (open access)

Design and Performance of Experimental Axial-Discharge Mixed-Flow Compressor 1: Impeller Design Theory

Memorandum presenting a description of an axial-discharge mixed-flow compressor, which is especially adapted for jet engines because of the large mass flow per unit frontal area. The best impeller was selected on the basis of the maximum air-flow capacity, which was 19.6 pounds per second for a 14-inch-diameter impeller with a tip speed of 1480 feet per second and a pressure ratio of 3.5.
Date: August 12, 1948
Creator: Goldstein, Arthur W.
System: The UNT Digital Library
Design and performance of experimental axial-discharge mixed-flow compressor 2: performance of impeller (open access)

Design and performance of experimental axial-discharge mixed-flow compressor 2: performance of impeller

Report presenting an analysis of an axial-discharge mixed-flow compressor designed to combine the compactness, reliability, and wide operating range of a mixed-flow compressor with the high flow capacity per unit of frontal area that characterizes the axial-flow compressor. The primary objective of this design was to maximize the flow capacity for a predetermined pressure ratio. Results regarding the flow distribution at the impeller inlet, flow distribution at the impeller outlet, and impeller performance are provided.
Date: August 12, 1948
Creator: Wilcox, Ward W.
System: The UNT Digital Library
A Comparison of Flight Measurements With Calculations of the Loss in Rolling Effectiveness Due to Wing Twist (open access)

A Comparison of Flight Measurements With Calculations of the Loss in Rolling Effectiveness Due to Wing Twist

"A flight investigation was conducted with a fighter-type airplane to determine the loss in rolling effectiveness due to wing twist, and the results are compared with the loss in rolling effectiveness calculated by use of a simplified method. The computed rolling velocities showed good agreement with experimentally determined rolling velocities throughout the Mach number range covered by the flights. Extrapolation of the flight data indicated a Mach number for reversal which agreed well with that obtained from calculations" (p. 1).
Date: August 27, 1948
Creator: Cooney, T. V. & Wollner, Bertram C.
System: The UNT Digital Library
Pressure Recovery at Supersonic Speeds Through Annular Duct Inlets Situated in a Region of Appreciable Boundary Layer 2: Effect of an Oblique Shock Wave Immediately Ahead of the Inlet (open access)

Pressure Recovery at Supersonic Speeds Through Annular Duct Inlets Situated in a Region of Appreciable Boundary Layer 2: Effect of an Oblique Shock Wave Immediately Ahead of the Inlet

Memorandum presenting an investigation of a model with a ramp that produced an oblique shock wave in front of an annular duct inlet, which was tested at Mach numbers between 1.36 and 2.01 to determine the effect of reducing the entrance Mach number on the total-pressure recovery after diffusion. The results showed that the maximum total-pressure recovery of the model investigated was considerably improved through the addition of a ramp.
Date: August 9, 1948
Creator: Brajnikoff, George B.
System: The UNT Digital Library
Comparison of two fuels in bumblebee 18-inch ram jet incorporating rake-type flame holder (open access)

Comparison of two fuels in bumblebee 18-inch ram jet incorporating rake-type flame holder

Report presenting an investigation to determine the performance of a Bumblebee 18-inch ram jet with a rake-type flame holder was conducted using kerosene and propylene oxide as fuels. Experiments occurred at a range of pressure altitudes and ram-pressure ratios over the operable range of fuel-air ratios. Use of propylene oxide was found to improve the stability of combustion, increased the operable range of fuel-air ratios, and allowed ignition at high values of combustion-chamber-inlet velocities.
Date: August 18, 1948
Creator: Wilcox, Fred A. & Howard, Ephraim M.
System: The UNT Digital Library
Free-Flight Investigation of the Rolling Effectiveness of Several Delta Wing - Aileron Configurations at Transonic and Supersonic Speeds (open access)

Free-Flight Investigation of the Rolling Effectiveness of Several Delta Wing - Aileron Configurations at Transonic and Supersonic Speeds

Report presenting testing of several delta wing-aileron configurations as part of a general investigation of their rolling effectiveness characteristics at transonic and supersonic speeds. Results regarding wing-aileron rolling effectiveness and drag are provided.
Date: August 27, 1948
Creator: Sandahl, Carl A.
System: The UNT Digital Library
Langley full-scale tunnel investigation of the characteristics in yaw of a trapezoidal wing of aspect ratio 4 with circular-arc airfoil sections (open access)

Langley full-scale tunnel investigation of the characteristics in yaw of a trapezoidal wing of aspect ratio 4 with circular-arc airfoil sections

Report presenting an investigation to determine the characteristics in yaw of a trapezoidal wing of aspect ratio 4 with circular-arc airfoil sections and 0.20-chord rear and drooped-nose flaps. Measurements of lift, lateral force, rolling moment, and yawing moment of four configurations were made for a range of angles of attack and yaw angles.
Date: August 30, 1948
Creator: May, Ralph W., Jr. & Stevens, George L.
System: The UNT Digital Library
Flight Tests of a Two-Dimensional Wedge Diffuser at Transonic and Supersonic Speeds (open access)

Flight Tests of a Two-Dimensional Wedge Diffuser at Transonic and Supersonic Speeds

"A two-dimensional wedge diffuser, designed to be used with a ducted-airfoil ram jet, was tested on a rocket-powered test vehicle up to a Mach number of 1.45. Orifice plates and a choking section behind the diffuser exit simulated burning in a combustion chamber by providing the proper pressure drop. Results obtained from these tests showed there was no abrupt changes in mass flow and pressure recovery as the model velocity increased through the transonic region" (p. 1).
Date: August 11, 1948
Creator: Faget, M. A.
System: The UNT Digital Library
Investigation of performance of Bumblebee 18-inch ram jet with a can-type flame holder (open access)

Investigation of performance of Bumblebee 18-inch ram jet with a can-type flame holder

Report presenting the results of an investigation in the altitude wind tunnel to determine the performance of a Bumblebee 18-inch ram jet equipped with a can-type flame holder. Results regarding the ramjet combustion performance and ramjet overall performance are provided.
Date: August 24, 1948
Creator: Sterbentz, W. H. & Nussdorfer, T. J.
System: The UNT Digital Library
Aerodynamic characteristics of a two-blade NACA 10-(3)(12)-03 propeller (open access)

Aerodynamic characteristics of a two-blade NACA 10-(3)(12)-03 propeller

From Introduction: "The particular blade design, the tests of which are described in the present paper, was one necessary to the investigation of the effect of differences in blade-thickness ratios."
Date: August 30, 1948
Creator: Allis, A. E. & Gray, W. H.
System: The UNT Digital Library
Analytical investigation of effect of water-cooled turbine blades on performance of turbine-propeller power plants (open access)

Analytical investigation of effect of water-cooled turbine blades on performance of turbine-propeller power plants

"Finally the work of the report is applied exclusively to consideration of the turbine-propeller power plant because previous performance analyses of the various gas-turbine propulsion systems combine with recent improvements in propeller design indicate that it is this combination which, will give the best over-all performance in the speed ranges considered" (p. 5).
Date: August 16, 1948
Creator: Bowman, William D
System: The UNT Digital Library
Theoretical and Experimental Analysis of Low-Drag Supersonic Inlets Having a Circular Cross Section and a Central Body at Mach Numbers 3.30, 2.75, and 2.45 (open access)

Theoretical and Experimental Analysis of Low-Drag Supersonic Inlets Having a Circular Cross Section and a Central Body at Mach Numbers 3.30, 2.75, and 2.45

Contains theoretical and experimental analysis of circular inlets having a central body at Mach numbers of 3.30, 2.75, and 2.45. The inlets have been designed in order to have low drag and high pressure recovery. The pressure recoveries obtained are of the same order of magnitude as those previously obtained by inlets having very large external drag.
Date: August 13, 1948
Creator: Ferri, Antonio & Nucci, Louis M.
System: The UNT Digital Library
Correlation of cylinder-head temperatures and coolant heat rejections of a multicylinder, liquid-cooled engine of 1710-cubic-inch displacement (open access)

Correlation of cylinder-head temperatures and coolant heat rejections of a multicylinder, liquid-cooled engine of 1710-cubic-inch displacement

"Data obtained from an extensive investigation of the cooling characteristics of four multicylinder, liquid-cooled engines have been analyzed and a correlation of both the cylinder-head temperatures and the coolant heat rejections with the primary engine and coolant variables was obtained. The method of correlation was previously developed by the NACA from an analysis of the cooling processes involved in a liquid-cooled-engine cylinder and is based on the theory of nonboiling, forced-convection heat transfer. The data correlated included engine power outputs from 275 to 1860 brake horsepower; coolant flows from 50 to 320 gallons per minute; coolants varying in composition from 100 percent water to 97 percent ethylene glycol and 3 percent water; and ranges of engine speed, manifold pressure, carburetor-air temperature, fuel-air ratio, exhaust-gas pressure, ignition timing, and coolant temperature" (p. 207).
Date: August 31, 1948
Creator: Lundin, Bruce T.; Povolny, John H. & Chelko, Louis J.
System: The UNT Digital Library