National Advisory Committee for Aeronautics (NACA) - 34 Matching Results

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Investigation of a two-step nozzle in an 11-inch hypersonic tunnel

Description: Report discussing flow surveys made of several nozzles using two 2-dimensional steps at Mach number 6.98. Results regarding wall-pressure surveys, disturbance patterns in expansion, total-pressure survey, temperature recovery, and general nozzle characteristics are provided.
Date: October 25, 1949
Creator: McLellan, Charles H.; Williams, Thomas W. & Bertram, Mitchel H.
Partner: UNT Libraries Government Documents Department

Performance of Single-Stage Turbine of Mark 25 Torpedo Power Plant with Two Special Nozzles, II, Efficiency with 20 Degrees-Inlet-Angle Rotor Blades

Description: A single-stage modification of the turbine from a Mark 25 torpedo power plant was investigated to determine the performance with two nozzle designs in combination with special rotor blades having a 20 inlet angle. The performance is presented in terms of blade, rotor, and brake efficiency as a function of blade-jet speed ratio for pressure ratios of 8, 15 (design), and 20. The blade efficiency with the nozzle having circular pas- sages (K) was equal to or higher than that with the nozzle having rectangular passages (J) for all pressure ratios and speeds investigated. The maximum blade efficiency of 0.571 was obtained with nozzle K at a pressure ratio of 8 and a blade-jet speed ratio of 0.296. The difference in blade efficiency was negligible at a pressure ratio of 8 at the low speeds; the maxim difference was 0.040 at a pressure ratio of 20 and a blade-jet speed ratio of 0.260.
Date: August 25, 1949
Creator: Schum, Harold J. & Whitney, Warren J.
Partner: UNT Libraries Government Documents Department

The effect of blade-section thickness ratio on the aerodynamic characteristics of related full-scale propellers at Mach numbers up to 0.65

Description: The results of an investigation of two 10-foot-diameter, two-blade NACA propellers are presented for a range of blade angles from 20 degrees to 55 degrees at airspeeds up to 500 miles per hour. These results are compared with those from previous investigations of five related NACA propellers in order to evaluate the effects of blade-section thickness ratios on propeller aerodynamic characteristics.
Date: April 25, 1949
Creator: Maynard, Julian D. & Steinberg, Seymour
Partner: UNT Libraries Government Documents Department

General algebraic method applied to control analysis of complex engine types

Description: "A general algebraic method of attack on the problem of controlling gas-turbine engines having any number of independent variables was utilized employing operational functions to describe the assumed linear characteristics for the engine, the control, and the other units in the system. Matrices were used to describe the various units of the system, to form a combined system showing all effects, and to form a single condensed matrix showing the principal effects. This method directly led to the conditions on the control system for noninteraction so that any setting disturbance would affect only its corresponding controlled variable" (p. 581).
Date: April 25, 1949
Creator: Boksenbom, Aaron S. & Hood, Richard
Partner: UNT Libraries Government Documents Department

Investigations of an Annular Diffuser-Fan Combination Handling Rotating Flow

Description: Memorandum presenting an investigation of two annular diffusers of different conical angles of expansion but constant outer diameters with rotating flow behind a fan. The performance characteristics are determined and the rotational-kinetic-energy effects on the overall energy transformation are observed over a range of inlet mach numbers from 0.1 to 0.44 and angles of flow up to 28 degrees.
Date: April 25, 1949
Creator: Schwartz, Ira R.
Partner: UNT Libraries Government Documents Department

Flight Investigation of 6.25-Inch-Diameter Deacon Rocket and 10-Inch-Scale Model Rocket

Description: Flight tests were conducted at the NACA Pilotless Aircraft Research Station, Wallops Island, to determine the characteristics of the Allegany Ballistics Laboratory's 6.2inch-diameter Deacon and lO-inch-scale model solid-propellant rocket motors. The tests were performed to assist in the development of these rockets which were designed for, and urgently needed to propel supersonic research models and pilotless aircraft. The tests showed that the rocket motors functioned properly under various flight- acceleration loads over a range of pre-ignition grain temperatures. A maximum velocity of 4180 feet per second was obtained at an elapsed time of 2.9 seconds with the 6.25-inch Deacon rocket motor at a gross weight of l9O pounds. Free-flight data of drag coefficient for the Deacon configuration for a Mach number range of 1.1 to 3.6 have been obtained from flight tests of several pounds. Camera studies of the take-off and flights of the Deacon rocket shared no evidence of breakup of propellant grains. An analysis of the forces to which the Deacon rocket grain is subjected was made. The analysis shows that the grain loading is most severe near the beginning and near the end of the rocket action time. The 10-inch-scale model rocket motor is a scaled model of the l6-inch- diameter multi-perforated, cast-grain rocket motor. A maximum velocity of 1625 feet per second at a time of 1.075 seconds was obtained at a gross weight of 309 pounds.
Date: March 25, 1949
Creator: Watson, R. S.
Partner: UNT Libraries Government Documents Department

An Investigation of a Full-Scale Model of the Republic XF-91 Airplane in the Ames 40- By 80-Foot Wind Tunnel: Pressure Data

Description: Wind-tunnel tests of a full-scale model of the Republic XF-91 airplane were conducted to determine the distribution of pressure over the external wing fuel tank installation and over the vee tail and ventral fin. The data were obtained for a range of angles of attack and sideslip and elerudder deflection angles; the presentation is in tabular form.
Date: March 25, 1949
Creator: Hunton, Lynn W. & Dew, Joseph K.
Partner: UNT Libraries Government Documents Department

A preliminary experimental investigation of a submerged cascade inlet

Description: Report presenting an experimental investigation of a submerged air inlet incorporating a cascade of airfoils for turning and diffusing the entering air. Variables associated with submerged air inlets and airfoil-cascade designs were considered, including changes to the ramp plan form and angle for the submerged inlet and the cascade-axis inclination, cascade-blade angle, solidity, and inclination of the center line of the duct for the cascade.
Date: March 25, 1949
Creator: Christiani, R. Duane & Randall, Lauros M.
Partner: UNT Libraries Government Documents Department

Equilibrium Operating Performance of Axial-Flow Turbojet Engines by Means of Idealized Analysis

Description: "A method of predicting equilibrium operating performance of turbojet engines has been developed, with the assumption of simple model processes for the components. Results of the analysis are plotted in terms of dimensionless parameters comprising critical engine dimensions and over-all operating variables. This investigation was made of an engine in which the ratio of axial inlet-air velocity to compressor-tip velocity is constant, which approximates turbojet engines with axial-flow compressors" (p. 673).
Date: February 25, 1949
Creator: Sanders, John C. & Chapin, Edward C.
Partner: UNT Libraries Government Documents Department

Free-flight investigation at transonic and supersonic speeds of the rolling effectiveness of a 42.7 degree sweptback wing having partial-span ailerons

Description: An investigation of the rolling effectiveness at transonic and supersonic speeds of partial-span ailerons on a 42.7 degree sweptback wing having symmetrical circular-arc airfoil sections of 10-percent thickness ratio normal to the wing quarter-chord line has been made by means of rocket-propelled test vehicles. The results are compared with results of a supersonic wind-tunnel test at Mach number 1.9.
Date: October 25, 1948
Creator: Sandahl, Carl A.
Partner: UNT Libraries Government Documents Department

NACA Transonic Wing-Tunnel Test Sections

Description: Memorandum presenting an approximate subsonic theory developed for the solid blockage interference in circular wind tunnels with walls slotted in the direction of flow. The theory indicated the possibility of obtaining zero blockage interference. Tests in a circular slotted tunnel based on the theory confirmed the theoretical predictions.
Date: October 25, 1948
Creator: Wright, Ray H. & Ward, Vernon G.
Partner: UNT Libraries Government Documents Department

Performance of J33-A-23 Turbojet-Engine Compressor, II, Over-All Performance Characteristics of Compressor with 34-Blade Impeller at Equivalent Impeller Speeds from 6000 to 11,750 RPM

Description: "The J33-A-23 compressor with a 34-blade impeller was operated at ambient inlet temperature and an inlet pressure of 14 inches mercury absolute over a range of equivalent impeller speeds from 6000 to 11,750 rpm. Additional runs at equivalent speeds of 7,000, 10,000, and 11,750 rpm and ambient inlet temperature were made at inlet pressures of 5 and 10 inches mercury absolute. The results of this investigation are compared with those of the J33-A-23 compressor with a 17-blade impeller" (p. 1).
Date: August 25, 1948
Creator: Beede, William L. & Kovach, Karl
Partner: UNT Libraries Government Documents Department

Preliminary free-flight investigation of the effect of airfoil section on aileron rolling effectiveness at transonic and supersonic speeds

Description: From Summary: "Results have been obtained by means of a free-flight technique utilizing rocket propulsion which indicate that aileron-rolling-effectiveness characteristics are affected adversely by variations in airfoil section which procedure large increases in the trailing-edge angle."
Date: June 25, 1948
Creator: Sandahl, Carl A.
Partner: UNT Libraries Government Documents Department

Preliminary investigation at a Mach number of 1.9 and a Reynolds number of 2,200,000 of three ailerons applicable to the Bell XS-2 airplane design

Description: Report presenting testing of a 42.7 degree sweptback tapered wing with three types of ailerons tested at a Mach number of 1.9 and a Reynolds number of 2,200,000; the wing geometry was similar to that of an XS-2 airplane. The purpose of the investigation was to determine the effectiveness of ailerons at these specified flight characteristics. Results regarding the aerodynamic characteristics of the wing are also provided.
Date: May 25, 1948
Creator: Sivells, James C. & Conner, D. William
Partner: UNT Libraries Government Documents Department

Wind-tunnel investigation of the low-speed stability and control characteristics of a model with a sweptback vee tail and a sweptback wing

Description: Report presenting testing in the 300 mph tunnel of a model with a sweptback vee tail and a sweptback wing to determine its low-speed stability and control characteristics. The results are compared to testing with the same tail panel with zero dihedral on the same wing-fuselage combination. The longitudinal stability characteristics, downwash at the tail, longitudinal control characteristics, lateral stability characteristics, and rudder control characteristics are provided.
Date: May 25, 1948
Creator: Polhamus, Edward C.
Partner: UNT Libraries Government Documents Department

Preliminary evaluation of the performance of a uniflow two-stroke-cycle spark-ignition engine combined with a blowdown turbine and a steady-flow turbine

Description: Report presenting calculations based on a theoretical analysis for a composite engine consisting of a uniflow two-stroke-cycle spark-ignition engine, a compressor, a blowdown turbine, and a steady-flow turbine. Operation of the engine is considered for four cases of gas mixtures and steady-flow turbine temperatures.
Date: November 25, 1947
Creator: Sather, Bernard I. & Foster, Hampton H.
Partner: UNT Libraries Government Documents Department

Acceleration Measurements During Landings of a 1/5.5-Size Dynamic Model of the Columbia XJL-1 Amphibian in Smooth Water and in Waves: Langley Tank Model 208M, TED No. NACA 2336

Description: A 1/5.5-size powered dynamic model of the Columbia XJL-1 amphibian was landed in Langley tank no. 1 in smooth water and in oncoming waves of heights from 2.1 feet to 6.4 feet (full-size) and lengths from 50 feet to 264 feet (full-size). The motions and the vertical accelerations of the model were continuously recorded. The greatest vertical acceleration measured during the smooth-water landings was 3.1g.
Date: September 25, 1947
Creator: Clement, Eugene P. & Havens, Robert F.
Partner: UNT Libraries Government Documents Department

An analysis of longitudinal-control problems encountered in flight at transonic speeds with a jet-propelled airplane

Description: From Introduction: "This report presents an analysis based on flight and wind-tunnel test data directed toward the determination of the probable cause of the pitch-up. Wing pressure distribution and stability and control characteristics in the dive are also included."
Date: September 25, 1947
Creator: Brown, Harvey H.; Rolls, L. Stewart & Clousing, Lawrence A.
Partner: UNT Libraries Government Documents Department

Determination of Stress-Rupture Parameters for Four Heat-Resisting Alloys

Description: Stress-rupture data for four heat-resisting alloys are analyzed according to equations of the theory of rate processes. A method for determining the four parameters of structure and composition is demonstrated and the four parameters are determined for each of the alloys: forged S816, cast S816, cast S590, and cast Vitallium. It is concluded that parameters can be determined for an alloy provided sufficient reliable experimental data are available.
Date: August 25, 1947
Creator: Lidman, William G.
Partner: UNT Libraries Government Documents Department

Investigation of Thrust Augmentation of a 1600-Pound Thrust Centrifugal-Flow-Type Turbojet Engine by Injection of Refrigerants at Compressor Inlets

Description: Investigations were conducted to determine effectiveness of refrigerants in increasing thrust of turbojet engines. Mixtures of water an alcohol were injected for a range of total flows up to 2.2 lb/sec. Kerosene was injected into inlets covering a range of injected flows up to approximately 30% of normal engine fuel flow. Injection of 2.0 lb/sec of water alone produced an increase in thrust of 35.8% of rate engine conditions and kerosene produced a negligible increase in thrust. Carbon dioxide increased thrust 23.5 percent.
Date: August 25, 1947
Creator: Jones, William L. & Dowman, Harry W.
Partner: UNT Libraries Government Documents Department

Flight-Test Evaluation of the Longitudinal Stability and Control Characteristics of 0.5-Scale Models of the Fairchild Lark Pilotless-Aircraft Configuration: Standard Configuration with Wing Flaps Deflected 60 Degrees and Model having Tail in Line with Wings, TED No. NACA 2387

Description: Flight tests were conducted at the Flight Test Station of the Pilotless Aircraft Research Division at Wallop Island, Va., to determine the longitudinal control and stability characteristics of 0.5-scale models of the Fairchild Lark pilotless aircraft with the tail in line with the wings a d with the horizontal wing flaps deflected 60 deg. The data were obtained by the use of a telemeter and by radar tracking.
Date: June 25, 1947
Creator: Stone, David G.
Partner: UNT Libraries Government Documents Department

Performance of a 20-inch steady-flow ram jet at high altitudes and ram-pressure ratios

Description: Report presenting the results of an investigation conducted in the altitude wind tunnel to determine the performance of a 20-inch ramjet. The investigation was conducted at a range of altitudes and ram-pressure ratios using preheated 62-octane fuel. A net thrust of 8135 pounds educed to standard sea-level conditions, a net-thrust coefficient of 0.74, and an overall efficiency of 12.6 percent were attained at Mach number 1.845 at which the engine with a 5-foot combustion chamber was operated.
Date: June 25, 1947
Creator: Perchonok, Eugene; Sterbentz, William H. & Wilcox, Fred A.
Partner: UNT Libraries Government Documents Department

Pressure-distribution measurements on a full-scale horizontal tail surface for a Mach number range of 0.20 to 0.70

Description: Report presenting testing of a full-scale, semispan, horizontal tail surface for a jet-propelled fighter airplane in the 16-foot high-speed tunnel to determine the variation of the chordwise and spanwise pressure distributions with Mach number. Surface irregularities were found to cause appreciable distortion of the pressure distribution. Results regarding chordwise distributions, spanwise distribution, effect of Mach number on root bending moment, and estimated critical Mach numbers are provided.
Date: June 25, 1947
Creator: Schueller, Carl F.
Partner: UNT Libraries Government Documents Department