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Aerodynamic characteristics of a wing with unswept quarter-chord line, aspect ratio 4, taper ratio 0.6, and NACA 65A004 airfoil section : transonic-bump method

Description: From Introduction: "This paper presents the results of the investigation of the wing alone and of the wing-fuselage configurations employing a wing with an unswept quarter-chord line, aspect ratio 4, taper ratio 0.6, and an NACA 65A004 airfoil section parallel to the air stream. The experimental results of a wing of identical plan from having an NACA 65A006 airfoil section which was tested as part of the transonic program are presented in reference 1.
Date: May 8, 1950
Creator: Myers, Boyd C , II & Wiggins, James W

Analysis of turbojet-engine controls for afterburning starting

Description: From Introduction: "The object of this report is to investigate the effects of after-burner lighting on the engine behavior and control-system requirements of a controlled turbojet engine. In this report, a simulation procedure for the afterburner is developed (based on ref. 3), this afterburner simulation is coordinated with previously developed nonafterburning-engine simulation procedures (ref. 4), and the compensated interacting control systems of references 1 and 2 are used. The results of an analog investigation of the the effects of an afterburner light on several controlled turbojet-engine configurations are reported and evaluated."
Date: October 8, 1956
Creator: Phillips, W E , Jr

Analytical and experimental investigation of the effects of compressor interstage air bleed on performance characteristics of a 13-stage axial-flow compressor

Description: Air was bled over the fifth-and tenth-stage rotor-blade rows through ports designed to pass 11 and 9 percent of the inlet flow, respectively, at 80 percent speed. Along the rated operating line the maximum speed at which rotating stall was encountered was lowered by either of these bleeds, and the stall patterns below these speeds were altered so that no dangerous resonant rotor-blade bending vibrations were excited. The combination of the two bleeds completely eliminated rotating stall to at least 50 percent speed. The compressor-discharge weight flow was decreased only at intermediate speeds, and the overall pressure ratio was affected only at intermediate speeds, and the overall pressure ratio was affected only by the combination bleed at intermediate speeds. Fifth-stage bleed increased compressor efficiency at low speeds, and tenth-stage bleed decreased efficiency at intermediate speeds.
Date: February 8, 1957
Creator: Lucas, James G; Geye, Richard P & Calvert, Howard F

An analytical method for evaluating factors affecting application of transpiration cooling to gas turbine blades

Description: From Introduction: "A survey of some of the advantages and problems associated with transpiration cooling of gas-turbine engines is given in reference 1, and its is shown therein that high pressure gradients around the periphery of gas-turbine blades require that the blade wall permeability be varied around the blade periphery in order for uniform cooling to be obtained over the entire blade surface. This fact is verified in experimental investigations of transpiration-cooled turbine blades mounted in a static cascade (references 2 and 3) where it is shown that although transpiration cooling results in extremely effective cooling in the midchord region of the blade, there are very large variations in the chordwise temperature distribution because of improper permeability variation."
Date: September 8, 1952
Creator: Esgar, Jack B

An analytical study of sideslip angles and vertical-tail loads in rolling pullouts as affected by some characteristics of modern high-speed airplane configurations

Description: From Introduction: "The rolling-pullout maneuver (any maneuver in which rolls occur during high g flight conditions) has been shown to be pertinent to design considerations from the standpoint of the loads produced on a vertical tail (refs. 1 to 3). In order to understand this problem better, the results of an analytical study of effects of large variations of some of the lateral-stability-derivative coefficients on the maximum angle of sideslip at first peak of its oscillation are presented in this paper. Also, expressions for estimating the effects of small variations of or errors in these coefficients on the maximum sideslip angle have been developed and are presented. "
Date: October 8, 1953
Creator: Stone, Ralph W , Jr

Characteristics of perforated diffusers at free-stream Mach number 1.90

Description: An investigation was conducted at Mach number 1.90 to determine pressure recovery and mass-flow characteristics of series of perforated convergent-divergent supersonic diffusers. Pressure recoveries as high as 96 percent were obtained, but at reduced mass flows through the diffuser. Theoretical considerations of effect of perforation distribution on shock stability in converging section of diffuser are presented and correlated with experimental data. A method of estimating relative importance of pressure recovery and mass flow on internal thrust coefficient basis is given and a comparison of various diffusers investigated is made.
Date: May 8, 1950
Creator: Hunczak, Henry R & Kremzier, Emil J

Comparison between prediction and experiment for all-movable wing and body combinations at supersonic speeds : lift, pitching moment, and hinge moment

Description: A simple method is presented for estimating lift, pitching-moment, and hinge-moment characteristics of all-movable wings in the presence of a body as well as the characteristics of wing-body combinations employing such wings. In general, good agreement between the method and experiment was obtained for the lift and pitching moment of the entire wing-body combination and for the lift of the wing in the presence of the body. The method is valid for moderate angles of attack, wing deflection angles, and width of gap between wing and body. The method of estimating hinge moment was not considered sufficiently accurate for triangular all-movable wings. An alternate procedure is proposed based on the experimental moment characteristics of the wing alone. Further theoretical and experimental work is required to substantiate fully the proposed procedure.
Date: August 8, 1952
Creator: Nielsen, Jack N; Kaattari, George E & Drake, William C

Coolant-Flow Calibrations of Three Simulated Porous Gas-Turbine Blades

Description: An investigation was conducted at the NACA Lewis laboratory to determine whether simulated porous gas-turbine blades fabricated by the Eaton Manufacturing Company of Cleveland, Ohio would be satisfactory with respect to coolant flow for application in gas-turbine engines. These blades simulated porous turbine blades by forcing the cooling air onto the blade surface through a large number of chordwise openings or slits between laminations of sheet metal or wire. This type of surface has a finite number of openings, whereas a porous surface has an almost infinite number of smaller openings for the coolant flow. The investigation showed that a blade made of sheet-metal laminations stacked on a support member that passed up through the coolant passage was completely unsatisfactory because of extremely poor coolant flow distribution over the blade surface. The flow distribution for two wire-wound blades was more uniform, but the pressure drop between the coolant supply pressure and the local pressure on the outside of the blades was too low by a factor ranging from 3 to 3.5 for the required coolant flow rates. The pressure drop could be increased by forcing the wires closer together during blade fabrication.
Date: March 8, 1951
Creator: Esger, Jack B. & Lea, Alfred L.