Calculated Effect of Uranium Distribution on Reflector Control Effectiveness for a Water-Moderated Power Reactor (open access)

Calculated Effect of Uranium Distribution on Reflector Control Effectiveness for a Water-Moderated Power Reactor

Report presenting two-group theory calculations to determine the effect of nonuniform uranium loading as compared to uniform loading on the reflector control effectiveness attainable in a large thermal reactor usable for aircraft power application. Results regarding reactivities and investments, uranium distributions, and power distributions are provided.
Date: January 22, 1954
Creator: Fox, Thomas A. & Valerino, Michael F.
System: The UNT Digital Library
Flight and Preflight Evaluation of an Automatic Thrust-Coefficient Control System in a Twin-Engine Ram-Jet Missile (open access)

Flight and Preflight Evaluation of an Automatic Thrust-Coefficient Control System in a Twin-Engine Ram-Jet Missile

Report presenting a flight and preflight evaluation of an automatic thrust-coefficient control system in a twin-engine ram-jet missile. A flicker-type single-loop servocontrol system is shown to be a usable way of controlling ram-jet thrust coefficients.
Date: January 22, 1954
Creator: Dettwyler, H. Rudolph & Trout, Otto F., Jr.
System: The UNT Digital Library
Mechanical design analysis of several noncritical air-cooled turbine disks and a corrugated-insert air-cooled turbine rotor blade (open access)

Mechanical design analysis of several noncritical air-cooled turbine disks and a corrugated-insert air-cooled turbine rotor blade

Report presenting a series of turbine wheel designs made for a turbojet engine with an axial-flow compressor. The designs were made to determine the influence of air-cooling on overall engine design, weight, critical-material content, and complexity and to assist with construction of research model full-scale turbines.
Date: July 22, 1953
Creator: Moseson, Merland L.; Krasner, Morton H. & Ziemer, Robert R.
System: The UNT Digital Library
The effect of nacelle combinations and size on the zero-lift drag of a 45 degree sweptback wing and body configuration as determined by free-flight tests at Mach numbers between 0.8 and 1.3 (open access)

The effect of nacelle combinations and size on the zero-lift drag of a 45 degree sweptback wing and body configuration as determined by free-flight tests at Mach numbers between 0.8 and 1.3

Investigation of the effect on zero-lift drag of varying the size and number of symmetrically mounted nacelles on a 45 degree sweptback wing and body combination as determined by free-flight tests of rocket-propelled models over a range of Mach and Reynolds numbers. The nacelle configuration consisted of a twin-engine nacelle near the fuselage, a combination of single-engine nacelles at the wing tip and fuselage, a large nacelle at the wing tip, and a large nacelle near the fuselage.
Date: June 22, 1953
Creator: Hoffman, Sherwood & Pepper, William B., Jr.
System: The UNT Digital Library
The effect of initial rate of subsonic diffusion on the stable subcritical mass-flow range of a conical shock diffuser (open access)

The effect of initial rate of subsonic diffusion on the stable subcritical mass-flow range of a conical shock diffuser

Report presenting results of a systematic study in the 8- by 6-foot supersonic wind tunnel to determine the effect that area distribution in the subsonic diffuser might have on stability and overall performance of conical-type supersonic diffusers. Drag, pressure recovery, and mass flow are presented for five diffusers designed for maximum mass flow at Mach number 2.0.
Date: July 22, 1953
Creator: Nettles, J. C.
System: The UNT Digital Library
High-altitude performance of 9.5-inch-diameter tubular experimental combustor with fuel staging (open access)

High-altitude performance of 9.5-inch-diameter tubular experimental combustor with fuel staging

Report presenting an investigation of 57 experimental tubular designs embodying adjacent fuel-rich and air-rich regions and axial staging of the fuel introduction at simulated high-altitude conditions. Results regarding the development of pilot, development of secondary-air admission sleeve, development of final configuration, and performance of best configuration are provided.
Date: March 22, 1954
Creator: Scull, Wilfred E.
System: The UNT Digital Library
Dynamic Stability and Control Characteristics of a Ducted-Fan Model in Hovering Flight (open access)

Dynamic Stability and Control Characteristics of a Ducted-Fan Model in Hovering Flight

Report presenting the results of an experimental investigation of the dynamic stability and control of a simple ducted-fan model in hovering flight in order to provide basic information on the stability and control of jet vertically rising airplanes in hovering flight. The investigation primarily consisted of flight tests with the model hovering at altitude and near the ground.
Date: April 22, 1954
Creator: Kirby, Robert H.
System: The UNT Digital Library
Experimental Effects of Propulsive Jets and Afterbody Configurations on the Zero-Lift Drag of Bodies of Revolution at a Mach Number of 1.59 (open access)

Experimental Effects of Propulsive Jets and Afterbody Configurations on the Zero-Lift Drag of Bodies of Revolution at a Mach Number of 1.59

The present investigation was made at a free-stream Mach number of 1.59 to compare the afterbody drags to a series of conical boattailed models at zero angle of attack. Afterbody drags were obtained for both the power-off and the power-on conditions. Power-on drags were obtained as a function of afterbody fineness ratio, jet pressure ratio and divergence, and jet Mach number.
Date: April 22, 1954
Creator: de Moraes, Carlos A. & Nowitzky, Albin M.
System: The UNT Digital Library
The change with mass-flow ratio of the cowl pressure drag of normal-shock inlets at supersonic speeds (open access)

The change with mass-flow ratio of the cowl pressure drag of normal-shock inlets at supersonic speeds

Report presenting pressure-drag coefficients and the changes in these coefficients with mass-flow ratio, which have been measured in tests of six open-nose conical cowls at an angle of attack of 0 degrees. Testing occurred in the Ames 8 by 8-inch supersonic wind tunnel at a range of Mach numbers. Results regarding pressure distributions, change in cowl pressure drag with mass-flow ratio, cowl pressure drag at a given mass-flow ratio, and changes in cowl pressure drag with mass-flow ratio as a function of Mach number are provided.
Date: June 22, 1956
Creator: Davis, Wallace F. & Gowen, Forrest E.
System: The UNT Digital Library
Free-flight measurements of the zero-lift drag of several wings at Mach numbers from 1.4 to 3.8 (open access)

Free-flight measurements of the zero-lift drag of several wings at Mach numbers from 1.4 to 3.8

Report presenting the zero-lift drag of several wings obtained at supersonic Mach numbers in free flight with rocket-propelled models. The wings tested all had the same exposed area, mounted on the same basic body configuration, and had one of four different types of wings.
Date: June 22, 1956
Creator: Jackson, H. Herbert
System: The UNT Digital Library
Fabrication Techniques and Heat-Transfer Results for Cast-Cored Air-Cooled Turbine Blades (open access)

Fabrication Techniques and Heat-Transfer Results for Cast-Cored Air-Cooled Turbine Blades

Memorandum presenting an investigation to devise an air-cooled turbine blade which eliminated the difficulties encountered with brazing in air-cooled-blade fabrication. Techniques were developed for casting air-cooled blades with a large number of relatively small cooling passages near the airfoil surface; two such blades of HS-21 material were operated in a turbojet engine modified for air cooling. Results regarding the heat-transfer characteristics, stress and durability results, and evaluation of cast-cored-blade potential are provided.
Date: June 22, 1956
Creator: Freche, John C. & Oldrieve, Robert E.
System: The UNT Digital Library
Preliminary evaluation of pentaborane in a 1/4-sector of an experimental annular combustor (open access)

Preliminary evaluation of pentaborane in a 1/4-sector of an experimental annular combustor

Report presenting an evaluation of a 1/4-sector of an annular combustor designed for use with pentaborane fuel at a simulated altitude condition. Results regarding the pentaborane performance, combustor development, and the JP-5 fuel performance are provided.
Date: May 22, 1957
Creator: Kaufman, Warner B.; Lezberg, Erwin A. & Breitwieser, Roland
System: The UNT Digital Library
Effect of Inlet-Guide-Vane Angle on Performance Characteristics of a 13-Stage Axial-Flow Compressor in a Turbojet Engine (open access)

Effect of Inlet-Guide-Vane Angle on Performance Characteristics of a 13-Stage Axial-Flow Compressor in a Turbojet Engine

Report presenting the effect of adjusting compressor inlet-guide-vane angle on overall compressor performance, stage performance, engine thrust, and specific fuel consumption in a 7000-pound-thrust turbojet engine. Data was obtained at several angles and demonstrated that increasing the guide-vane angle decreased the weight flow at the higher compressor speeds. It had no effect on stage performance other than at the first stage, where it reduced maximum flow, pressure, and temperature coefficients.
Date: May 22, 1956
Creator: Medeiros, Arthur A. & Calvert, Howard F.
System: The UNT Digital Library
Analytical and experimental investigation of a temperature-schedule acceleration control for a turbojet engine (open access)

Analytical and experimental investigation of a temperature-schedule acceleration control for a turbojet engine

From Introduction: "This report investigates some of the problems involved in scheduling the tailpipe temperature to avoid stall during acceleration. The object of this report is to investigate the dynamics of a closed-loop acceleration control that follows a schedule of tailpipe temperature with rotor speed."
Date: June 22, 1958
Creator: Heppler, Herbert; Stiglic, Paul M. & Novik, David
System: The UNT Digital Library
Investigation of the Use of Area Suction to Increase the Effectiveness of Trailing-Edge Flaps of Various Spans on a Wing of 45 Degree Sweepback and Aspect Ratio 6 (open access)

Investigation of the Use of Area Suction to Increase the Effectiveness of Trailing-Edge Flaps of Various Spans on a Wing of 45 Degree Sweepback and Aspect Ratio 6

Report discusses the results of an investigation of a model of a wing of 45 degree sweepback and aspect ratio 6 to determine the aerodynamic characteristics and suction requirements for boundary-layer control by means of area suction applied to trailing-edge flaps. Various flap spans and flap deflections were tested. The measured values of the coefficients were compared to the calculated values.
Date: June 22, 1956
Creator: Griffin, Roy N., Jr. & Hickey, David H.
System: The UNT Digital Library
Temperatures in a J47-25 turbojet-engine turbine section during steady-state and transient operation in an altitude test stand (open access)

Temperatures in a J47-25 turbojet-engine turbine section during steady-state and transient operation in an altitude test stand

Report presenting a J47-25 engine instrumented with thermocouples and operated under steady-state and transient-conditions in an altitude test stand to determine the operating temperatures at altitude in the turbine section of a turbojet engine. Results regarding the temperature effects and transient operation are provided.
Date: May 22, 1956
Creator: Morse, C. R. & Johnston, J. R.
System: The UNT Digital Library
Investigation of two-stage counterrotating compressor I : design and over-all performance of transonic first compressor stage (open access)

Investigation of two-stage counterrotating compressor I : design and over-all performance of transonic first compressor stage

Report presenting a highly loaded transonic rotor which was designed, built, and tested as part of a two-stage counterrotating-compressor research program. The design conditions were chosen to explore the upper limits of loading and Mach number for the transonic unit. The complete rotor design procedure is presented as well as the recorded stall traces and techniques for obtaining the data.
Date: May 22, 1956
Creator: Wilcox, Ward W. & Wright, Linwood C.
System: The UNT Digital Library
Effect of fuels on screaming in 200-pound-thrust liquid-oxygen - fuel rocket engine (open access)

Effect of fuels on screaming in 200-pound-thrust liquid-oxygen - fuel rocket engine

Report presenting the tendencies of 14 different fuels and three fuel blends to produce high-frequency oscillatory combustion (screaming) in a 200-pound-thrust, water-cooled, liquid-oxygen-fuel rocket engine. The fuels, in order of increasing screaming tendency, were hydrazines, branched-chain paraffins, aromatics, and amines, and straight-chain paraffins. Results regarding screaming tendency and screaming amplitude are provided.
Date: June 22, 1956
Creator: Pass, Isaac & Tischler, Adelbert O.
System: The UNT Digital Library
Static stability and control of canard configurations at Mach numbers from 0.70 to 2.22 : longitudinal characteristics of a triangular wing and canard (open access)

Static stability and control of canard configurations at Mach numbers from 0.70 to 2.22 : longitudinal characteristics of a triangular wing and canard

Report presenting the results of an investigation of the static longitudinal stability and control characteristics of a canard airplane configuration without analysis for a range of Mach numbers. Data are presented for a variety of angles of attack and canard angles.
Date: January 22, 1958
Creator: Boyd, John W. & Peterson, Victor L.
System: The UNT Digital Library
Investigation of Two-Stage Counterrotating Compressor. 3: Design of Second-Stage Rotor and Preliminary Over-All Performance (open access)

Investigation of Two-Stage Counterrotating Compressor. 3: Design of Second-Stage Rotor and Preliminary Over-All Performance

At the design speed of a two-stage counterrotating compressor, an overall average pressure ratio of 4.3 was obtained at a specific weight flow of 27.2 pounds per second per square foot frontal area with an adiabatic efficiency of 0.75. Preliminary tests indicate that a weight-flow mismatching exists between the two rotors that causes the first rotor to operate at less than peak efficiency at design speed. At lower speeds, the first stage was forced to operate in the stalled region in single-stage tests. With the second rotor installed, no periodic rotating stall was observed, although random fluctations of similiar magnitude were noted.
Date: October 22, 1956
Creator: Wilcox, Ward W. & Wright, Linwood C.
System: The UNT Digital Library
The Effect of Compressor-Inlet Water Injection on Engine and Afterburner Performance (open access)

The Effect of Compressor-Inlet Water Injection on Engine and Afterburner Performance

Report presenting testing of a turbojet engine incorporating a conventional-type afterburner over a range of afterburner pressure levels and engine-inlet water-air ratios. At each pressure level and water-air ratio, the afterburner fuel flow was varied from lean blowout to maximum burner-outlet temperature. Results regarding the effects of water vapor on engine performance, effects of water vapor on afterburner performance, and high Mach number performance with water injection are provided.
Date: July 22, 1958
Creator: Sivo, Joseph N.; Wanhainen, John P. & Jones, William L.
System: The UNT Digital Library
Performance of five short multielement turbojet combustors for hydrogen fuel in quarter-annulus duct (open access)

Performance of five short multielement turbojet combustors for hydrogen fuel in quarter-annulus duct

Report presenting an investigation of five short multielement turbojet combustors designed for use with hydrogen fuel tested in a quarter-annulus duct. One combustor had an array of U-gutter flame-holders, while the other four were manifold arrays of swirl-can combustor elements. Results regarding combustion efficiency, temperature profiles, pressure loss, durability, comparison with previous short combustors, and operation with propane fuel are provided.
Date: July 22, 1958
Creator: Jones, Robert E. & Rayle, Warren D.
System: The UNT Digital Library
Drag of Conical and Circular-Arc Boattail Afterbodies at Mach Numbers From 0.6 to 1.3 (open access)

Drag of Conical and Circular-Arc Boattail Afterbodies at Mach Numbers From 0.6 to 1.3

"Drag characteristics of a series of related conical and circular-arc afterbodies are presented for Mach numbers from 0.6 to 1.3. Drag was obtained from pressure measurements on the boattail and solid base. The boattail angles tested ranged from 0 degrees to 45 degrees for ratios of base diameter to maximum body diameter ranging from 0 to 1.0" (p. 1).
Date: January 22, 1957
Creator: Silhan, Frank V. & Cubbage, James M., Jr.
System: The UNT Digital Library
Investigation of axially symmetric flow over steps at transonic speeds with comparisons of estimated and experimental drag results (open access)

Investigation of axially symmetric flow over steps at transonic speeds with comparisons of estimated and experimental drag results

Report presenting an investigation of the problem of predicting the experimental wave drag for configurations which have discontinuities in area distribution and thus infinite theoretical wave drag. The agreement between the experimental and computed drags of the ring-body combinations without fillets was very poor. Results regarding the drag coefficients and estimation of wave drag and pressure coefficients and estimation of total drag are provided.
Date: July 22, 1957
Creator: Holdaway, George H. & Wallace, Minor R., Jr.
System: The UNT Digital Library