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Experimental Investigation of Air-Cooled Turbine Blades in Turbojet Engine 2: Rotor Blades With 15 Fins in Cooling-Air Passages
Report presenting an investigation to experimentally determine the effectiveness of air-cooling several configurations of turbine blades in a turbojet engine. The results of the second blade configuration, which consists of a hollow blade shell with 15 fins inserted, are provided. The factors involved in the design of the blade configuration are also included.
Radiant Heat Transfer From Flames in a Single Tubular Turbojet Combuctor
Memorandum presenting an investigation to determine the energy transfer by thermal radiation from the flame of a single tubular turbojet-engine combustor to the combustor liner. The effects of variations in combustor inlet-air pressure, fuel-air ratio, and air mass flow on the transfer of radiant energy were studied.
Experimental Investigation of Air-Cooled Turbine Blades in Turbojet Engine: 1: Rotor Blades With 10 Tubes in Cooling-Air Passages
Report presenting an investigation to experimentally determine the effectiveness of air cooling several turbine-blade configurations in a turbojet engine. The results obtained with the first configuration, which was a hollow blade shell with 10 tube inserts, are presented. A description of factors leading to the design are provided as well as the correlated cooled-blade temperatures, solid-blade temperatures, cooling-air-temperature increase through radial passages, and blade failure are provided.
Investigation at Mach Number 1.91 of Spreading Characteristics of Jet Expanding From Choked Nozzles
Report presenting an investigation at Mach number 1.91 to determine the gross spreading characteristics of jets expanding from convergent and convergent-divergent nozzles using total-temperature surveys. Results regarding the preliminary development and jet spreading characteristics of the different types of nozzles are provided.
Cooling Characteristics of a Transpiration-Cooled Afterburner With a Porous Wall of Brazed and Rolled Wire Cloth
Memorandum presenting cooling data for a transpiration-cooled afterburner with a porous combustion-chamber wall of brazed and rolled wire cloth for a range of exhaust-gas temperatures, total flow ratio of cooling air to combustion gas, and pressure altitudes. Maximum wall temperatures based on the cooling correlation were determined for a porous wall of uniform permeability at sea-level takeoff and for several flight Mach numbers. Results regarding typical data, cooling correlation, transpiration-cooling performance, comparison of transpiration and forced-convection cooling, and pressure environment of wire cloth are provided.
Fabrication and Properties of Hot-Pressed Molybdenum Disilicide
Report presenting an investigation of hot-pressed molbdenum disilicide bodies produced by industrial processes at a temperature of 2950 degrees and a pressure of 3000 pounds per square inch. Results regarding the short-time tensile strength, stress-rupture data, compression strength, air-corrosion resistance, hardness, coefficient of linear thermal expansion, thermal conductivity, and density are provided.
Investigations of Air-Cooled Turbine Rotors for Turbojet Engines 1: Experimental Disk Temperature Distribution in Modified J33 Split-Disk Rotor at Speeds up to 6000 RPM
"An experimental investigation is being conducted at the Lewis laboratory to establish general principles for the design of noncritical turbine rotor configurations. This investigation includes evaluation of cooling effectiveness, structural stability, cooling-air flow distribution characteristics, and methods of supplying cooling air to the turbine rotor blades. Prior to design of a noncritical rotor, a standard turbine rotor of a commerical turbojet engine was split in the plane of rotation and machined to provide a passage for distributing cooling air to the base of each blade" (p. 1).
Experimental Investigation of Air-Cooled Turbine Blades in Turbojet Engine. 7: Rotor-Blade Fabrication Procedures
"An experimental investigation was conducted to determine the cooling effectiveness of a wide variety of air-cooled turbine-blade configurations. The blades, which were tested in the turbine of a - commercial turbojet engine that was modified for this investigation by replacing two of the original blades with air-cooled blades located diametrically opposite each other, are untwisted, have no aerodynamic taper, and have essentially the same external profile. The cooling-passage configuration is different for each blade, however" (p. 1).
Interpretation of boundary-layer pressure-rake data in flow with a detached shock
From Summary: "A procedure is presented for determining boundary-layer quantities from pressure-rake data, which include the combined effects of viscous and shock losses. The problem is analyzed using schileren photographs of the shock configuration, the continuity of mass relationship, and the characteristics of the turbulent boundary layer that its outer edge is defined by a rapid change in slope in the Mach-number profiles in the vicinity of the edge."
Investigations of Slot Configurations for Film-Cooled Turbine Blades by Flow Visualization Methods
Memorandum presenting a procedure for obtaining qualitative information on the effectiveness of different slot configurations to make the flow of the cooling air visible. Two methods are utilized: one utilizes the traces caused by a reaction between paint spread over the blade surface and a gas mixed with the cooling air, while the other utilized smoke mixed with the cooling air to make it visible. From the visual observations, the use of a continuous slot as a means of creating the cooling film over the blade surface appeared to be superior to the use of holes or grooves.
Experimental Study of Isothermal Wake-Flow Characteristics of Various Flame-Holder Shapes
"An investigation of the isothermal wake-flow characteristics of several flame-holder shapes was carried out in a 4- by 4-inch flow chamber. The effects of flame-holder-shape changes on the characteristics of the Karman vortices and thus on the recirculation zones to which experimenters have related the combustion process were obtained for several flame holders. The results may furnish a basis of correlation, of combustion efficiency and stability for similarly shaped flame holders in combustion studies" (p. 1).
Relation of Turbojet Propulsion System Development to the Strategic Bomber Mission
Memorandum presenting a generalized analysis of the effects of turbojet propulsion system development and fuel selection on ability of a strategic bomber to perform desired and minimum missions. The variation of bomber performance using a hydrocarbon, boron, or nuclear fuel is discussed.
Large-Scale Wind-Tunnel Tests of an Airplane Model With a 45 Degree Sweptback Wing of Aspect Ratio 2.8 With Area Suction Applied to Trailing-Edge Flaps and With Several Wing Leading-Edge Modifications
Memorandum presenting an investigation of an airplane model to determine the effect of area suction trailing-edge flaps and several leading-edge modifications on the aerodynamic characteristics of a 45 degree sweptback wing. The wing had an aspect ratio of 2.8 and a taper ratio of 0.17.
Spark Ignition of Flowing Gases. 2: Effect of Electrode Parameters on Energy Required to Ignite a Propane-Air Mixture
From Summary: "Research was conducted to determine the effect of the electrode parameters of spacing, configuration, and material' on the energy required for ignition of a flowing propane-air mixture. In addition, the data were used to indicate the energy distribution along the spark length and to confirm previous observations concerning the effect of spark duration on ignition energy requirements. The data were obtained with a mixture at a fuel-air ratio of 0.0835 (by weight), a pressure of 3 inches of mercury absolute, a temperature of 80 F, and a mixture velocity of 5 feet per second."
Analysis of a Pneumatic Probe for Measuring Exhaust-Gas Temperatures with Some Preliminary Experimental Results
"A pneumatic probe based on continuity of mass flow through two restrictions separated by a cooling chamber was constructed to measure gas temperature at and beyond the limit of thermocouples. This probe consisted of a subsonic flat-plate orifice for the first restriction and a sonic-flow converging-diverging nozzle for the second restriction. The effect of variation in gas constants on the calibration is examined for common engine-exhaust gases" (p. 1).
Experimental Investigation of Average Heat-Transfer and Friction Coefficients for Air Flowing in Circular Tubes Having Square-Thread-Type Roughness
"An investigation of forced-convection heat transfer and associated pressure drops was conducted with air flowing through electrically heated Inconel tubes having various degrees of square-thread-type roughness, an inside diameter of 1/2 inch, and a length of 24 inches were obtained for tubes having conventional roughness ratios (height of thread/radius of tube) of 0 (smooth tube), 0.016, 0.025, and 0.037 over ranges of bulk Reynolds numbers up to 350,000, average inside-tube-wall temperatures up to 1950deg R, and heat-flux densities up to 115,000 Btu per hour per square foot" (p. 1).
Chemical and Physical Properties of Modified Hi-Cal-2
Memorandum presenting some physical and chemical properties of a sample of modified Hi-Cal-2. Some of the results obtained include chemical analysis, heat of combustion, density, freezing point, self-ignition temperature, flash point, oxygen stability, water stability test, infrared spectrum, and vapor pressure and decomposition are provided.
Investigation of a 1/4-Scale Model of the Republic F-105 Airplane in the Langley 19-Foot Pressure Tunnel: Influence of Trailing-Edge Flap Span and Deflection on the Longitudinal Characteristics
Report presenting development tests on a model of the Republic F-105 airplane at a Mach number of 0.20. The purpose of the current investigation is to obtain the longitudinal force and moment characteristics of the model equipped with trailing-edge flaps of various spans and deflections. Results regarding the longitudinal stability characteristics and effect of the horizontal tail are provided.
Wind-Tunnel Investigation of a 0.6-Scale Model of Hughes MX-904 Tail Surface at Supersonic Speeds: Tail Attached to a Segment of the Foreshortened Body
"An investigation has been made of a partial-span model of the tail surface designed for use on the Hughes Falcon (MX-904) missile to determine the aerodynamic characteristics of the tail and elevator including elevator hinge moment. Data obtained at Mach numbers of 1.62 and 1.96 in the Langley 9- by 12-inch supersonic blowdown tunnel are presented for the condition where the tail was attached to a segment of the foreshortened body" (p. 1).
A Wind-Tunnel Investigation of the Stability of the Antisubmarine Rocket Mk 1 Mod 0
Report discussing an investigation to determine the cause and provide a fix for the instability in flight of the antisubmarine rocket Mk 1 Mod 0. The Magnus effects and their nonlinear variation with angle of attack were found to affect the stability, so reducing the Magnus effects should reduce instability in the missiles. The greatest reduction of Magnus effects was found through a combination of nose-ring spoiler and the original direction of the propeller rotation, but the nose ring increased the drag.
An Investigation of the Longitudinal Stability Characteristics of Three Specialized Store Configurations at Transonic Speeds
Report presenting testing to determine the longitudinal stability characteristics of the TX-17, the "Short Seven", and the TX-21 special weapons. Dynamic and static stability data are provided for a range of Mach numbers and stagnation-pressure levels.
An Investigation of the Longitudinal Stability and Afterbody Pressure Characteristics of Specialized Store Configurations at Transonic Speeds
Report presenting an investigation to determine the longitudinal stability and afterbody pressure characteristics of the TX-14 and TX-16 special weapons at transonic and supersonic speeds. Results regarding dynamic testing and pressure testing are provided.
Wind-Tunnel Investigation of the Descent Characteristics of Bodies of Revolution Simulating Anti-Personnel Bombs
"An investigation has been conducted in the Langley 20-foot free spinning tunnel to study the relative behavior in descent of a number of homogeneous balsa bodies of revolution simulating anti-personnel bombs with a small cylindrical exploding device suspended approximately 10 feet below the bomb. The bodies of revolution included hemispherical, near-hemispherical, and near-paraboloid shapes. The ordinates of one near-paraboloid shape were specified by the Office of the Chief of Ordnance, U. S. Army" (p. 1).
Preliminary Flight Measurements of the Total-Pressure Recovery of a Split-Wing Ram-Jet Inlet at Mach Numbers from 1.4 to 3.16
"Flight tests were made to determine the total-pressure recovery of a split-wing ram-jet inlet with a fixed area exit 20 percent larger than the inlet throat over a Mach number range from 1.4 to 3.16. Total-pressure-recovery measurements at the diffuser exist station indicated abrupt pressure changes in the total-pressure profile throughout the Mach number range. Comparisons of average total-pressure recovery with the theoretical total-pressure recovery showed good agreement" (p. 1).
Investigation of a 1/22-Scale of the Republic F-105 Airplane in the Langley 8-Foot Transonic Tunnel: Static Longitudinal Stability and Control and Performance Characteristics at Transonic Speeds
Report presenting an investigation of the aerodynamic characteristics of various configurations of the Republic F-105 in the transonic tunnel at Mach numbers from 0.60 to 1.13. Results in this report include the static longitudinal stability and control characteristics, the effect of various configuration modifications on lift-drag ratio, the effect of subsonic and supersonic inlets and external stores, and the effect of area-distribution modifications on performance.
Preliminary Performance Data Obtained in a Full-Scale Free-Jet Investigation of a Side-Inlet Supersonic Diffuser
Report discussing an investigation into the performance of several modifications of a side-inlet ramjet engine diffuser. Total-pressure-recovery profiles, Mach number profiles, longitudinal wall static pressure distributions, and variation of the average-static to average-total pressure are presented.
Investigation of a 1/4-Scale Model of the Republic F-105 Airplane in the Langley 19-Foot Pressure Tunnel: Lateral Control and Directional Stability and Control Characteristics of Model Equipped With Drooped, Supersonic-Type, Elliptical Wing-Root Inlet
Report presenting low-speed testing of the Republic F-105 airplane in the pressure tunnel to determine the plane's lateral control and directional stability and control characteristics. Various combinations of components were tested, including tares, spoilers, ailerons, and wing fences.
Flutter Tests of a 1/25-Scale Model of the B-36J/RF-84F Tip-Coupled Airplane Configuration in the Langley 19-Foot Pressure Tunnel
Report discussing tests of a model of a B-36J/RF-84F tip-coupled airplane to evaluate the flutter characteristics where bomber-body freedoms are allowed and to obtain information about the dynamic stability characteristics. The variables studied were the skew angle of the fighter-bomber coupling, the fighter longitudinal position, the fighter and bomber loading, angle of sideslip, degrees of body freedom, and number of fighters. Flutter was primarily found to occur when the fighter roll frequency was near the natural chordwise-bending frequency of the bomber wing.
Wind-Tunnel Investigation of the Aerodynamic Characteristics of a 0.07-Scale Model of the North American MX-770 Missile
Report presenting the results of an investigation at supersonic speeds to determine the aerodynamic characteristics of a model of the North American MX-770 missile at several designated Mach numbers. No analysis is provided. Information about the longitudinal aerodynamic characteristics with trimmer and elevon deflected and lateral aerodynamic characteristics are described.
Wind-Tunnel Investigation of the Drag and Lateral-Stability Characteristics of a 1/22-Scale Model of a Bomber Airplane Employing a Low-Aspect-Ratio Triangular Wing
Report presenting the results of an investigation of cross-sectional-area distribution, nacelle configuration, and landing-gear-fairing configuration on the minimum drag characteristics of a model of a four-engine bomber airplane with a low-aspect-ratio triangular wing. The lateral stability characteristics are also included.
Comparative Study of Turbofan and Turbojet Engines
Report presents a comparison of turbofan and turbojet engines for Mach numbers of up to 3.0 and conventional hydrocarbon fuels. There are four parts of the report: a cycle analysis of turbofan engines and information about their designs, a comparison of several commercial engines proposed for the Air Force, component performance and development problems for turbofan and turbojet engines, and a summary and conclusions based on mission studies.
Transonic Aerodynamic Characteristics of a 1/15-Scale Model of the Convair B-58 Airplane
Report presenting an investigation of a model of the Convair B-58 airplane weapons system in the transonic tunnel for a range of Mach and Reynolds numbers. Results regarding drag characteristics, lift-curve slope, and longitudinal stability parameter are provided.
Investigation of the Kingfisher XAUM-2 Flying Torpedo in the Langley Full Scale Tunnel, TED No. NACA DE 327
Report presenting an investigation of a model of the Kingfisher XAUM-2 flying torpedo to determine the pressure recoveries within the jet engine nacelle and to determine the effects of several changes in model configuration on the aerodynamic characteristics of the model. The effectiveness of elevons and tabs as control devices was also investigated.
Preliminary Transonic Flutter Investigation of Models of T-Tall of Blackburn NA-39 Airplane
Report discussing a transonic flutter investigation of models of the T-tail of the Blackburn NA-39 airplane. The investigation was made at a variety of Mach numbers at simulated altitudes extending to below sea level. The Mach numbers at which asymmetric flutter and symmetric oscillations occur are presented.
An Investigation of the Afterbody Pressure Distribution and Fin Loading Characteristics of a Specialized Store Configuration at Transonic Speeds
Report presenting an investigation in the transonic pressure tunnel to determine the afterbody pressure distribution and fin loading characteristics of two configurations of the TX-21 special weapon. The only different in the two configurations was the nose contour, with one having a hemispherical-flat shape and one with a double-radius ogive-flat shape. Results regarding the pressure port, fin loads, and force measurements are provided.
Hovering and Transition Flight Tests of a 1/5-Scale Model of the Ryan X-13 VTOL Airplane
Report discussing an investigation of the dynamic stability and control characteristics of a model of the Ryan X-13 jet VTOL airplane in hovering and transition flight. Flight control was smooth and easy without the gyroscopic effects of the engine represented, but adding a simulation of the gyroscopic effects caused the plane to become uncontrollable in hovering flight without artificial stabilization. The transition was found to be easy to perform with and without gyroscopic effects, but the model had a tendency to fly in roll and slideslipped attitudes.
Some Notes on the Probable Damage to an Intercontinental-Ballistic-Missile Warhead Following Puncture of the Heat Shield
Report discussing a study of the effects of puncturing the heat shield of an intercontinental-ballistic-missile warhead by small projectiles. Calculations were created for both rod and sphere projectiles and experimental testing was performed on a missile model with holes drilled in the heat shield. The possibility that a projectile could have enough energy to cause mechanical damage to the interior of the warhead is also presented.
Comparison of Various Heat Exchangers for Liquid-Metal Nuclear Turbojet Over Range of Flight and Operating Conditions
Memorandum presenting an analysis of a large number of liquid-metal-to-air heat-exchanger cores for the nuclear-powered liquid-metal turbojet cycle to determine which types yield the best overall net thrust per total engine weight. The performances of all exchangers considered were initially evaluated at a median condition. The performance of the best of each of the four types was compared with that of a shell-and-tube exchanger with the air flowing through the tubes, operating at the same condition.
Preliminary Evaluation of the Wing Leading Edge as a Missile-Mounting Location
Report discussing testing to evaluate some of the major aspects of mounting and launching missiles from the leading edge of a wing, including experimentation with six missile models at several Mach numbers. Information from flight tests and launching tests is provided.
Analysis of rocket, ramjet, and turbojet engines for supersonic propulsion of long-range missiles. 3: Ramjet engine performance
Report presenting ramjet engine performance data over a range of engine design variables to permit selection and evaluation of a ramjet engine configuration for a long-range supersonic missile. Results include engine thrust, drag, fuel consumption, area ratios, and weight, and are suitable for use in design studies of missiles incorporating either internally or externally mounted ramjet engines.
Analysis of Rocket, Ramjet, Turbojet Engines for Supersonic Propulsion of Long-Range Missiles 2: Rocket Missile Performance
Memorandum presenting an investigation of the theoretical performance of a two-stage ballistic rocket missile with a centerbody and two parallel boosters for JP4-oxygen and ammonia-fluorine propellants. The missile using the ammonia-fluorine propellant weighs about one-half as much as a missile using JP4-oxygen. Results regarding the optimum missile and effect of variation of design parameters are provided.
Preliminary Investigation of Reflections of Oblique Waves from a Porous Wall
"A porous wall was used in an attempt to eliminate reflections of oblique waves from a tunnel wall. Calculations were made of the required resistance characteristics of a wall in order that the flow through the wall, due to the pressure difference across a shock wave, would equal the component normal to the wall of the flow behind the shock wave. The resistance characteristic of a sintered bronze wall was measured and the reflections of waves impinging on the wall were observed at a Mach number of 1.62" (p. 1).
Measurement and Analysis of Turbulent Flow Containing Periodic Flow Fluctuations
Memorandum presenting techniques for the measurement of the energy spectrum of flow fluctuations in both axial and lateral flow directions. A simple spectrum analysis is presented by which quantitative distinction may be made between turbulence and the flow disturbances associated with sound waves in ducts. Results regarding the measurement and analysis of turbulent-flow fields containing random and periodic flow fluctuations, effect of random sound disturbances on turbulence spectrum, and effect of combustion on combustor approach-stream spectrum are provided.
Investigation of Noise Field and Velocity Profiles of an Afterburning Engine
From Summary: "Sound pressure levels, frequency spectrum, and jet velocity profiles are presented for an engine-afterburner combination at various values of afterburner fuel - air ratio. At the high fuel-air ratios, severe low-frequency resonance was encountered which represented more than half the total energy in the sound spectrum. At similar thrust conditions, lower sound pressure levels were obtained from a current fighter air craft with a different afterburner configuration. The lower sound pressure levels are attributed to resonance-free afterburner operation and thereby indicate the importance of acoustic considerations in afterburner design."
Analytical determination of local surface heat-transfer coefficients for cooled turbine blades from measured metal temperatures
From Summary: "Procedures for applying these analytical methods to experimentally measured blade-metal temperatures are presented. Data are presented for the leading and trailing edge of a symmetrical water-cooled blade to illustrate the validity of the methods for those portions of the blade. In addition to the application to turbine blades, the methods can be applied to any heat-transfer apparatus having a profile that can be approximated by the shape discussed."
Analysis of Heat Transfer and Fluid Friction for Fully Developed Turbulent Flow of Supercritical Water With Variable Fluid Properties in a Smooth Tube
From Summary: "Calculated velocity and temperature distributions, as well as relations among Nusselt number, Reynolds number, and friction factor, are presented."
Experimental and Analytical Study of Balanced-Diaphragm Fuel Distributors for Gas-Turbine Engines
"A method of distributing fuel equally to a plurality of spray nozzles in a gas-turbine engine by means of balanced-diaphragm fuel distributors is presented. The experimental performance of three of eight possible distributor arrangements are discussed. An analysis of all eight arrangements is included. Criterions are given for choosing a fuel-distributor arrangement to meet specific fuel-system requirements of fuel-distribution accuracy, spray-nozzle pressure variations, and fuel-system pressures" (p. 1).
Interference Effects of Fuselage-Stored Missiles on Inlet Duct Model of an Interceptor-Type Aircraft at Mach Numbers 1.5 to 1.9
Memorandum presenting the effect of missile armament on the performance of an interceptor-type aircraft model at Mach numbers 1.5, 1.7, and 1.9 and at angles of attack up to 19 degrees. The aircraft model was characterized by triangular-shaped normal-shock inlets located at wing roots. Results regarding force measurements, effect of armament on inlet-duct performance, fuselage boundary-layer survey, and total-pressure contours at inlet throat and diffuser exit are provided.
Experimental Investigation of Extreme Internal Flow Turning at the Cowl Lip of an Axisymetric Inlet at a Mach Number of 2.95
Memorandum presenting an experimental investigation of the pressure-recovery performance of a fixed-geometry, two-cone, two-drag inlet at Mach number 2.95. Low drag was achieved by use of an internally cylindrical cowl with rapid flow turning that was within 4 degrees of the wedge angle for shock detachment. Results regarding the inlet performance and evaluation of inlet performance are provided.
Aerodynamic Heating of Blunt Nose Shapes at Mach Numbers Up to 14
From Introduction: "The importance of blunt noses as a means of reducing the heat transfer to high velocity missiles has recently received much publicity. The question of just what blunt shape is best is still moot, and it is the purpose of this paper to present and examine some recent experimental results which may throw some light on this problem."
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