Performance characteristics of an underslung vertical-wedge inlet with porous suction at Mach numbers of 0.63 and 1.5 to 2.0 (open access)

Performance characteristics of an underslung vertical-wedge inlet with porous suction at Mach numbers of 0.63 and 1.5 to 2.0

Performance characteristics of underslung vertical wedge inlet with porous suction at Mach numbers of 0.63 and 1.5 to 2.0.
Date: August 3, 1956
Creator: Allen, John L. & Piercy, Thomas G.
System: The UNT Digital Library
Altitude-wind-tunnel investigation of operational characteristics of J47 turbojet engine (open access)

Altitude-wind-tunnel investigation of operational characteristics of J47 turbojet engine

Report presenting an investigation in the altitude wind tunnel to determine the operational characteristics of a J47 turbojet engine over a wide range of simulated flight conditions at a range of altitudes. Operational characteristics investigated include operating range, starting, altitude and airspeed compensation of the fuel regulator, and acceleration.
Date: August 3, 1950
Creator: Bloomer, Harry E.
System: The UNT Digital Library
Error in airspeed measurement due to the static-pressure field ahead of an airplane at transonic speeds (open access)

Error in airspeed measurement due to the static-pressure field ahead of an airplane at transonic speeds

The magnitude and variation of the static-pressure error for various distances ahead of sharp-nose bodies and open-nose air inlets and for a distance of 1 chord ahead of the wing tip of a swept wing are defined by a combination of experiment and theory. The mechanism of the error is discussed in some detail to show the contributing factors that make up the error. The information presented provides a useful means for choosing a proper location for measurement of static pressure for most purposes.
Date: August 3, 1955
Creator: O'Bryan, Thomas C.; Danforth, Edward C. B. & Johnston, J. Ford
System: The UNT Digital Library
Preliminary Results of an Altitude-Wind-Tunnel Investigation of an Axial-Flow Gas Turbine-Propeller Engine 2 - Windmilling Characteristics (open access)

Preliminary Results of an Altitude-Wind-Tunnel Investigation of an Axial-Flow Gas Turbine-Propeller Engine 2 - Windmilling Characteristics

Wind tunnel investigations were performed to determine the performance properties of an axial-flow gas turbine-propeller engine II. Windmilling characteristics were determined for a range of altitudes from 5000 to 35,000 feet, true airspeeds from 100 to 273 miles per hour, and propeller blade angles from 4 degrees to 46 degrees.
Date: August 3, 1948
Creator: Conrad, E. W. & Durham, J. D.
System: The UNT Digital Library
Performance of J33-A-21 and J33-A-23 Turbojet-Engine Compressors with Water Injection (open access)

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

"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.
System: The UNT Digital Library
Altitude-Wind-Tunnel Investigation of a 4000-Pound-Thrust Axial-Flow Turbojet Engine, Part 1, Performance and Windmilling Drag Characteristics (open access)

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

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.
System: The UNT Digital Library
Drag Near Zero Lift of a 1/7-Scale Model of the Convair B-58 External Store as Measured in Free Flight Between Mach Numbers of 0.8 and 2.45 (open access)

Drag Near Zero Lift of a 1/7-Scale Model of the Convair B-58 External Store as Measured in Free Flight Between Mach Numbers of 0.8 and 2.45

"The zero-lift drag of a 1/7-scale model of the Convair B-58 external store was obtained at mach numbers between 0.8 and 2.45 at corresponding Reynolds numbers per foot of 3.5 x 10 to the 6th power and 15.3 X 10 to the 6th power. The experimental drag data are compared with calculated values at both subsonic and supersonic speeds and show good agreement. In addition to the drag data, some static stability derivatives and damping factors were also obtained and are presented with the predicted values of these derivatives for completeness and for comparison" (p. 1).
Date: August 3, 1955
Creator: Hopko, Russell N.
System: The UNT Digital Library
Effect of unequal air-flow distribution from twin inlet ducts on performance of an axial-flow turbojet engine (open access)

Effect of unequal air-flow distribution from twin inlet ducts on performance of an axial-flow turbojet engine

Report presenting an investigation in the NACA altitude test chamber to determine the effect of inlet-air-flow distortion on the performance of an axial-flow turbojet engine with simulated twin inlet ducts. Results regarding the pressure and temperature profiles, component performance, overall engine performance, and operational comments are provided.
Date: August 3, 1954
Creator: Walker, Curtis L.; Sivo, Joseph N. & Jansen, Emmert T.
System: The UNT Digital Library
Theoretical Investigation Based on Experimental Frequency-Response Measurements of an Automatic Altitude Control in Combination With Supersonic Missile Configuration (open access)

Theoretical Investigation Based on Experimental Frequency-Response Measurements of an Automatic Altitude Control in Combination With Supersonic Missile Configuration

Report presenting an analysis of an investigation of a simple altitude control based on static-pressure and rate-of-climb sensing is combined with a supersonic missile as a servomechanism to yield the closed-loop behavior of the entire system. The control system was found to function successfully at a low-altitude missile of the boost-guide type and would likely perform well at high altitude.
Date: August 3, 1954
Creator: Seaberg, Ernest C.; Geller, Edward S. & Willoughby, William W.
System: The UNT Digital Library
A method for increasing the effectiveness of stabilizing surfaces at high supersonic Mach numbers (open access)

A method for increasing the effectiveness of stabilizing surfaces at high supersonic Mach numbers

Report presenting the use of wedge-shaped airfoil sections to obtain large increases in lift-curve slope at low angles of attack at high supersonic Mach numbers. The use of such sections on the tail surfaces operating at low angles of attack on airplanes or missiles traveling at these speeds can greatly decrease the stabilizing-surface area required.
Date: August 3, 1954
Creator: McLellan, Charles H.
System: The UNT Digital Library
Investigation of a high-temperature single-stage turbine suitable for air cooling and turbine stator adjustment 2: performance of vortex turbine at various stator settings (open access)

Investigation of a high-temperature single-stage turbine suitable for air cooling and turbine stator adjustment 2: performance of vortex turbine at various stator settings

Report presenting a consideration of a mode of engine operation that requires operational flexibility of the turbine, which requires that the turbine stator and exhaust nozzle area are adjusted to maintain a fixed compressor operating point. Results regarding turbine performance and comparison of predicted and experimental turbine performance are provided.
Date: August 3, 1954
Creator: Heaton, Thomas R.; Holeski, Donald E. & Forrette, Robert E.
System: The UNT Digital Library
Performance characteristics of an underslung vertical-wedge inlet with porous suction at Mach numbers of 0.63 and 1.5 to 2.0 (open access)

Performance characteristics of an underslung vertical-wedge inlet with porous suction at Mach numbers of 0.63 and 1.5 to 2.0

Report presenting testing of the performance of a ventrally mounted inlet having a variable-angle vertical-wedge compression surface determined at several Mach numbers for angles of attack, angles of yaw, and wedge angle. A solid wedge and wedges with two different porosities were tested. Results regarding the inlet flow-field survey, comparison of inlet configurations, performance of the inlet, effect of free-stream Mach number at angle of attack of 2 degrees, effect of angles of attack and yaw, diffuser total-pressure distortion, fuselage boundary-layer-removal scoop, and effective thrust comparison are provided.
Date: August 3, 1956
Creator: Allen, John L. & Piercy, Thomas G.
System: The UNT Digital Library
Boundary-layer transition at supersonic speeds (open access)

Boundary-layer transition at supersonic speeds

"Recent results of the effects of Mach number, stream turbulence, leading-edge geometry, leading-edge sweep, surface temperature, surface finish, pressure gradient, and angle of attack on boundary-layer transition are summarized. Factors that delay transition are nose blunting, surface cooling, and favorable pressure gradient. Leading-edge sweep and excessive surface roughness tend to promote early transition. The effects of leading-edge blunting on two-dimensional surfaces and surface cooling can be predicted adequately by existing theories, at least in the moderate Mach number range" (p. 1).
Date: August 3, 1956
Creator: Low, George M.
System: The UNT Digital Library
Study of ram-air heat exchangers for reducing turbine cooling-air temperature of a supersonic aircraft turbojet engine (open access)

Study of ram-air heat exchangers for reducing turbine cooling-air temperature of a supersonic aircraft turbojet engine

The sizes and weights of the cores of heat exchangers were determined analytically for possible application for reducing turbine cooling-air temperatures of an engine designed for a Mach number of 2.5 and an altitude The sizes and weights of the cores of heat exchangers were determined analytically for possible application for reducing turbine cooling-air temperatures of an engine designed for a Mach number of 2.5 and an altitude of 70,000 feet. A compressor-bleed-air weight flow of 2.7 pounds per second was assumed for the coolant; ram air was considered as the other fluid. Pressure drops and inlet states of both fluids were prescribed, and ranges of compressor-bleed-air temperature reductions and of the ratio of compressor-bleed to ram-air weight flows were considered.
Date: August 3, 1956
Creator: Diaguila, Anthony J.; Livingood, John N. B. & Eckert, Ernst R. G.
System: The UNT Digital Library