Technical Report Archive and Image Library (TRAIL) - 172 Matching Results

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Aerodynamic characteristics of a circular cylinder at Mach number 6.86 and angles of attack up to 90 degrees

Description: Pressure-distribution and force tests of a circular cylinder have been made in the Langley 11-inch hypersonic tunnel at a Mach number of 6.88, a Reynolds number of 129,000, and angles of attack up to 90 degrees. The results are compared with the hypersonic approximation of Grimminger, Williams, and Young and a simple modification of the Newtonian flow theory. An evaluation of the crossflow theory is made through comparison of present results with available crossflow Mach number drag coefficients.
Date: January 1957
Creator: Penland, Jim A
Partner: UNT Libraries Government Documents Department

Aerodynamic Forces and Moments on a Large Ogive-Cylinder Store at Various Locations Below the Fuselage Center Line of a Swept-Wing Bomber Configuration at a Mach Number of 1.61

Description: A supersonic wind-tunnel investigation on store interference has been conducted in the Langley 4- by 4-foot supersonic pressure tunnel at a Mach number of 1.61. Forces and moments were measured on a large ogive-cylinder store in the presence of a 45 deg swept-wing-fuselage bomber configuration for a number of store locations below the fuselage center line. Results of the investigation show that large variations of store lift, drag, and pitch occur with changes in store or airplane angle of attack, store vertical location, and store horizontal location. The variation of the store forces and moments with respect to the chordwise location of the wing plan form indicates that the wing is a large factor in producing the interference loads on the store. Comparison of data for underfuselage and underwing store locations at an angle of attack of 0 deg showed maximum store drag interferences of similar magnitudes, but showed considerably smaller maximum interference on store lift an pitching moments for underfuselage store locations.
Date: January 14, 1957
Creator: Morris, O. A.
Partner: UNT Libraries Government Documents Department

Aerodynamic interference of slender wing-tail combinations

Description: From Introduction: "In the present paper, the emphasis is placed on calculating the variations of total forces and moments with angles of attack and sideslip for a number of slender plane and cruciform wing-tail combinations and for some airplane-type arrangements of a plane wing and a horizontal and vertical tail."
Date: January 1957
Creator: Sacks, Alvin H
Partner: UNT Libraries Government Documents Department

Altitude free-jet investigation of dynamics of a 28-inch-diameter ram-jet engine

Description: From Introduction: "The feasibility of closed-loop control of ram-jet-engine thrust is demonstrated in references 1 and 2. The dynamic behavior of a 28-inch-diameter ram-jet engine designed to operate in Mach number range of 2.35 to 2.70 is evaluated herein."
Date: January 15, 1957
Creator: Crowl, R. J.; Dunbar, W. R. & Wentworth, C. B.
Partner: UNT Libraries Government Documents Department

Analysis of efficiency characteristics of a single-stage turbine with downstream stators in terms of work and speed requirements

Description: One-dimensional mean-section flow and blade specific losses proportional to average specific kinetic energy are assumed in the analysis. Range of the work-speed parameter lambda considered includes low to moderate blade speeds with high specific work outputs, where critical turbojet, turbopump, and accessory-drive turbines are encountered. A diffusion factor of 0.5 limits the loading on the downstream stators. Turbine efficiences considered are total or aerodynamic, rating, and static. Efficiences of velocity-diagram types at impulse and that corresponding to values of maximum efficiency are presented and compared to indicate in what range of lambda downstream stators are beneficial as well as the attending improvements in efficiency.
Date: January 23, 1957
Creator: Wintucky, William T & Stewart, Warner L
Partner: UNT Libraries Government Documents Department

Analysis of fluorine addition to the vanguard first stage

Description: From Introduction: "This report presents data pertinent to the problem of boosting rocket performance by adding up to 30 percent liquid fluorine to the liquid oxygen of an existing oxygen-hydrocarbon rocket engine."
Date: January 24, 1957
Creator: Tomazic, William A; Schmidt, Harold W & Tischler, Adelbert O
Partner: UNT Libraries Government Documents Department

Analytical investigation of the effect of water injection on supersonic turbojet-engine - inlet matching and thrust augmentation

Description: From Introduction: "In order to provide engine-inlet matching to prevent such mass flow spillage and the attendant drags, much mechanical complication has been introduced. References 1 and 2 propose employing this principle at subsonic and supersonic speeds to achieve thrust augmentation. The merits of the system for supersonic engine-inlet airflow matching, as well as thrust augmentation, appear considerable; and a comparative study with existing fixed- and variable-geometry inlets was therefore undertaken."
Date: January 1957
Creator: Beke, Andrew
Partner: UNT Libraries Government Documents Department

Application of a windshield-display system to the low-altitude bombing problem

Description: From Introduction: "The design and flight evaluation of an airborne target simulator for use in tracking studies of fighter-type airplanes equipped with optical gunsights have recently been reported (ref. 1). In this equipment the target airplane was represented by a movable dot of light projected on the windshield of the test airplane."
Date: January 4, 1957
Creator: Barnett, Robert M; Kaufman, William M & Fulcher, Elmer C
Partner: UNT Libraries Government Documents Department

A balanced-pressure sliding seal used for transfer of pressurized air between stationary and rotating parts

Description: A combination sliding-ring and pressure-balancing seal capable of transferring pressurize air from stationary to rotating parts was developed and experimentally investigated at sliding velocities and cooling-air pressures up to 10,000 feet per minute and 38.3 pounds per square inch absolute, respectively. Leakage of cooling air was completely eliminated with an expenditure of balance air less than one-fourth the leakage loss of air from labyrinth seals under the same conditions. Additional cooling of the carbon-base seal rings was required, and the maximum wear rate on the rings was about 0.0005 inch per hour.
Date: January 9, 1957
Creator: Curren, Arthur N & Cochran, Reeves P
Partner: UNT Libraries Government Documents Department

Base pressure at supersonic speeds on two-dimensional airfoils and on bodies of revolution with and without fins having turbulent boundary layers

Description: An analysis has been made of available experimental data to show the effects of most of the variables that are more predominant in determining base pressure at supersonic speeds. The analysis covers base pressures for two-dimensional airfoils and for bodies of revolution with and without stabilizing fins and is restricted to turbulent boundary layers. The present status of available experimental information is summarized as are the existing methods for predicting base pressure. A simple semiempirical method is presented for estimating base pressure. For two-dimensional bases, this method stems from an analogy established between the base-pressure phenomena and the peak pressure rise associated with the separation of the boundary layer. An analysis made for axially symmetric flow indicates that the base pressure for bodies of revolution is subject to the same analogy. Based upon the methods presented, estimations are made of such effects as Mach number, angle of attack, boattailing, fineness ratio, and fins. These estimations give fair predictions of experimental results. (author).
Date: January 1, 1957
Creator: LOVE EUGENE S
Partner: UNT Libraries Government Documents Department

Basic considerations in the combustion of hydrocarbon fuels with air

Description: Basic combustion research is collected, collated, and interpreted as it applies to flight propulsion. The following fundamental processes are treated in separate chapters: atomization and evaporation of liquid fuels, flow and mixing processes in combustion chambers, ignition and flammability of hydrocarbon fuels, laminar flame propagation, turbulent flames, flame stabilization, diffusion flames, oscillations in combustors, and smoke and coke formation in the combustion of hydrocarbon-air mixtures. Theoretical background, basic experimental data, and practical significance to flight propulsion are presented.
Date: January 1, 1957
Creator: Barnett, Henry C & Hibbard, Robert R
Partner: UNT Libraries Government Documents Department

Bodies of revolution having minimum drag at high supersonic airspeeds

Description: Approximate shapes of nonlifting bodies having minimum pressure foredrag at high supersonic airspeeds are calculated. With the aid of Newton's law of resistance, the investigation is carried out for various combinations of the conditions of given body length, base diameter, surface area, and volume. In general, it is found that when body length is fixed, the body has a blunt nose; whereas, when the length is not fixed, the body has a sharp nose. The additional effect of curvature of the flow over the surface is investigated to determine its influence on the shapes for minimum drag. The effect is to increase the bluntness of the shapes in the region of the nose and the curvature in the region downstream of the nose. These shape modifications have, according to calculation, only a slight tendency to reduce drag. Several bodies of revolution of fineness ratios 3 and 5, including the calculated shapes of minimum drag for given length and base diameter and for given base diameter and surface area, were tested at Mach numbers from 2.73 to 6.28. A comparison of theoretical and experimental foredrag coefficients indicates that the calculated minimum-drag bodies are reasonable approximations to the correct shape.
Date: January 1, 1957
Creator: Eggers, A J , Jr; Resnikoff, Meyer M & Dennis, David H
Partner: UNT Libraries Government Documents Department

Cloud-droplet ingestion in engine inlets with inlet velocity ratios of 1.0 and 0.7

Description: The paths of cloud droplets into two engine inlets have been calculated for a wide range of meteorological and flight conditions. The amount of water in droplet form ingested by the inlets and the amount and distribution of water impinging on the inlet walls are obtained from these droplet-trajectory calculations. In both types of inlet, a prolate ellipsoid of revolution represents either part or all of the forebody at the center of an annular inlet to an engine. The configurations can also represent a fuselage of an airplane with side ram-scoop inlets. The studies were made at an angle of attack of 0 degree. The principal difference between the two inlets studied is that the inlet-air velocity of one is 0.7 that of the other. The studies of the two velocity ratios lead to some important general concepts of water ingestion in inlets.
Date: January 1, 1957
Creator: Brun, Rinaldo J
Partner: UNT Libraries Government Documents Department

Combustor performance of a 16-inch ram jet using gaseous hydrogen as fuel at Mach number 3.0

Description: An investigation was conducted in the NACA Lewis 10- by 10-foot supersonic wind tunnel to evaluate the performance of three burner configurations in a 16-inch ram jet with gaseous hydrogen as fuel. Data were obtained over a fuel-air-ratio range from 0.0030 to 0.0260 (stoichiometric = 0.0292) at a free-stream Mach number of 3.0 and 0 degree angle of attack. The exit nozzle-throat area ratios employed were 0.60 and 0.75.
Date: January 18, 1957
Creator: Wasserbauer, Joseph F & Wilcox, Fred A
Partner: UNT Libraries Government Documents Department

Comparison of calculated and experimental load distributions on thin wings at high subsonic and sonic speeds

Description: A method for calculating the aerodynamic loading on a wing in combination with a body is presented. Calculated results are compared with experimentally measured data for two wing-body configurations throughout a range of Mach number up to 1.0. The magnitude and the distribution of spanwise loading of the calculated data are generally in good agreement with the experimental data.
Date: January 1, 1957
Creator: Crigler, John L
Partner: UNT Libraries Government Documents Department

Comparison of effect of a turbojet engine and three cold-flow configurations on the stability of a full-scale supersonicle inlet

Description: Increasing the volume and length of the duct behind the inlet affected the inlet stability at Mach 2.0 and zero angle of attack. Close approximation of the inlet stability limit of the J34 engine-inlet configuration was obtained by a cold-pipe configuration having a length and volume approaching that measured to the engine turbine. Variation of these parameters had a small effect on the minimum subcritical stable mass flow below a cowl-lip-position parameter of 44 degrees and appeared to have a negligible effect on the inlet pressure-recovery - mass-flow curve. Initial buzz frequency and minimum cowl-lip-position parameter for complete buzz-free operation varied with configuration.
Date: January 24, 1957
Creator: Musial, Norman T
Partner: UNT Libraries Government Documents Department

Comparison of experimental with theoretical total-pressure loss in parallel-walled turbojet combustors

Description: An experimental investigation of combustor total-pressure loss was undertaken to confirm previous theoretical analyses of effects of geometric and flow variables and of heat addition. The results indicate that a reasonable estimate of cold-flow total-pressure-loss coefficient may be obtained from the theoretical analyses. Calculated total-pressure loss due to heat addition agreed with experimental data only when there was no flame ejection from the liner at the upstream air-entry holes.
Date: January 9, 1957
Creator: Dittrich, Ralph T
Partner: UNT Libraries Government Documents Department