Technical Report Archive and Image Library (TRAIL) - 67 Matching Results

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Altitude-Wind-Tunnel Investigation of the 19B-2, 19B-8, and 19XB-1 Jet Propulsion Engines, 3, Performance and Windmilling Drag Characteristics

Description: The performance characteristics of the 19B-8 and 19XB-1 turbojet engines and the windmilling-drag characteristics of the 19B-6 engine were determined in the Cleveland altitude wind tunnel. The investigations were conducted on the 19B-8 engine at simulated altitudes from 5000 to 25,000 feet with various free-stream ram-pressure ratios and on the 19XB--1 engine at simulated altitudes from 5000 to 30,000 feet with approximately static free-stream conditions. Data for these two engines are presented to show the effect of altitude, free-stream ram-pressure ratio, and tail-pipe-nozzle area on engine performance. A 21-percent reduction in tail-pipe-nozzle area of the 19B-8 engine increased the let thrust 43 percent the net thrust 72 percent, and the fuel consumption 64 percent. An increase in free-stream ram-pressure ratio raised the jet thrust and the air flow and lowered the net thrust throughout the entire range of engine speeds for the 19B-8 engine. At similar operating conditions, the corrected jet thrust and corrected air flow were approximately the same for both engines, and the corrected specific fuel consumption based on jet thrust was lower for the 19XB-1 engine than for the 19B-8 engine. The thrust and air-flow data obtained with both engines at various altitudes for a given free-stream rampressure ratio were generalized to standard sea-level atmospheric conditions. The performance parameters involving fuel consumption generalized only at high engine speeds at simulated altitudes as high as 15,000 feet. The windmilling drag of the 19B-8 engine increased rapidly as the airspeed was increased.
Date: March 13, 1957
Creator: Fleming, WIlliam A. & Dietz, Robert O., Jr.
Partner: UNT Libraries Government Documents Department

Analysis of experimental low-speed loss and stall characteristics of two-dimensional compressor blade cascades

Description: From Introduction: "In the present report, the concept of velocity diffusion is applied in an analysis of blade losses expressed in terms of the fundamental parameter of wake momentum thickness. Restrictions and limitations involved in the application of the results to cascade performance analyses are discussed."
Date: March 19, 1957
Creator: Lieblein, Seymour
Partner: UNT Libraries Government Documents Department

Comparison of Experimental and Theoretical Zero-Lift Wave-Drag Results for Various Wing-Body-Tail Combinations at Mach Numbers up to 1.9

Description: Comparisons are made of experimental and theoretical zero-lift wave drag for several nose shapes, wing-body combinations, and models of current airplanes at Mach numbers up to 1.0. The experimental data were obtained from tests in the Ames 6- by6-foot supersonic wind tunnel and at the NACA Wallops Island facility. The theoretical drag was found by use of linear theory utilizing model area distributions. The agreement between theoretical and experimental zero-lift wave-drag coefficients was generally very good, especially for a fuselage or for fuselage-wing combinations that were vertically symmetrical. For other models that had rapid changes in body shape and/or were not vertically symmetrical, the agreement of theory with experiment ranged from fair to poor, depending on the severity of the change in shape.
Date: March 27, 1957
Creator: Petersen, R. B.
Partner: UNT Libraries Government Documents Department

Comparison of NACA 65-series compressor-blade pressure distributions and performance in a rotor and in cascade

Description: An investigation has been conducted to compare the performance of NACA 65-series compressor blades in two-dimensional cascade with that in an axial flow compressor. Blade pressure distributions were obtained by the use of a mercury-seal pressure-transfer device. The comparison indicated that cascade data accurately predicted the turning angle and blade pressure distribution obtained in the compressor at design conditions.
Date: March 1, 1957
Creator: Westphal, Willard R & Godwin, William R
Partner: UNT Libraries Government Documents Department

Conceptual Design of an Advanced Engineering Test Reactor

Description: From abstract: This report describes a conceptual design for an Advanced Engineering Test Reactor. The reactor is a large graphite assembly penetrated by parallel Zircaloy tubes through which flow as heavy water solution of uranyl sulfate. Reactor power is 220 megawatts.
Date: March 1, 1957
Creator: Mallon, R. G.; Saldick, J. & Gibbons, R. E.
Partner: UNT Libraries Government Documents Department

Experimental comparison of speed : fuel-flow and speed-area controls on a turbojet engine for small step disturbances

Description: Optimum proportional-plus-integral control settings for speed - fuel-flow control, determined by minimization of integral criteria, correlated well with analytically predicted optimum settings. Engine response data are given for a range of control settings around the optimum. An inherent nonlinearity in the speed-area loop necessitated the use of nonlinear controls. Response data for two such nonlinear control schemes are presented.
Date: March 1, 1957
Creator: Wenzel, L M; Hart, C E & Craig, R T
Partner: UNT Libraries Government Documents Department

Experimental investigation of temperature feedback control systems applicable to turbojet-engine control

Description: Temperature - fuel-flow and temperature-area feedback control systems were investigated as means of controlling tailpipe gas temperature of a turbojet engine during transient operation in the high-speed region. Proportional-plus-integral control was used in both systems, but in the temperature-area control system it was necessary to add nonlinear components to the basic proportional-plus-integral control to provide satisfactory transient response to a desired step increase in temperature. Time integral of temperature-error functions were used as criteria for determining optimum transient response. A description of engine dynamics was obtained from frequency-response data.
Date: March 1, 1957
Creator: Hart, C E; Wenzel, L M & Craig, R T
Partner: UNT Libraries Government Documents Department

Flight tests of a model of a high-wing transport vertical-take-off airplane with tilting wing and propellers and with jet controls at the rear of the fuselage for pitch and yaw control

Description: An investigation of the stability and control of a high-wing transport vertical-take-off airplane with four engines during constant-altitude transitions from hovering to normal forward flight was conducted with a remotely controlled free-flight model. The model had four propellers distributed along the wing with the thrust axes in the wing chord plane. The wing could be rotated to 90 degrees incidence so that the propeller thrust axes were vertical for hovering flight. An air jet at the rear of the fuselage provided pitch and yaw control for hovering and low-speed flight.
Date: March 1, 1957
Creator: Lovell, Powell M , Jr & Parlett, Lysle P
Partner: UNT Libraries Government Documents Department