National Advisory Committee for Aeronautics (NACA) - 222 Matching Results

Search Results

Results: 1 - 50 next
Aerodynamic characteristics and pressure distributions of a 6-percent-thick 49 degree sweptback wing with blowing over half-span and full-span flaps
From Introduction: "The investigation reported herein was initiated to define further the effects on the aerodynamic characteristics and load distribution of a thin, sweptback wing of a low-pressure blowing system and also to provide information on which to base a more thorough study of a complete airplane configuration."
Aerodynamic Characteristics Including Scale Effect of Several Wings and Bodies Alone and in Combination at a Mach Number of 1.53
From Introduction: "In the present report, the results for the wings and bodies of revolution alone are first analyzed in comparison with exiting theory."
Aerodynamic characteristics of a wing with quarter-chord line swept back 45 degrees, aspect ratio 6, taper ratio 0.6, and NACA 65A009 airfoil section
From Introduction: "This paper presents the results of the investigation of the wing-alone and wing-fuselage configurations employing a wing with the quarter-chord line swept back 45^o, aspect ratio 4, taper ratio 0.3, and an NACA 65A006 airfoil section parallel to the stream."
Aerodynamic characteristics of NACA RM-10 missile in 8- by 6-foot supersonic wind tunnel at Mach numbers from 1.49 to 1.98 1: presentation and analysis of pressure measurements (stabilizing fins removed)
Experimental investigation of flow about a slender body of revolution (NACA RM-10 missile) aligned and inclined to a supersonic stream was conducted at Mach numbers from 1.49 to 1.98 at a Reynolds number of approximately 30,000,000. Boundary-layer measurements at zero angle of attack are correlated with subsonic formulations for predicting boundary-layer thickness and profile. Comparison of pressure coefficients predicted by theory with experimental values showed close agreement at zero angle of attack and angle of attack except over the aft leeward side of body. At angle of attack, pitot pressure measurements in plane of model base indicated a pair of symmetrically disposed vortices on leeward side of body.
Aerodynamic control of supersonic inlets for optimum performance
From Introduction: "The purpose of this paper is to discuss and evaluate some of the input signals or control parameters which have been experimentally employed to operate turbojet inlet-control systems. These include the normal-shock position, the oblique-shock position, and the diffuser-exit Mach number. The discussion is based on results obtained at the NACA Lewis laboratory during control investigations of ram-jet engines (ref. 1 to 5) and during a study on the control of a supersonic inlet for the J34 turbojet engine (refs 6 and 7)."
Aerodynamic Load Distribution on a 45 Degree Sweptback Wing With Leading-Edge Chord-Extensions at Transonic Speeds, Including Effects of a Spoiler-Slot-Deflector Aileron
Report discussing the aerodynamic loading characteristics of a 45 degree sweptback wing with leading-edge chord extensions, including the effects of a spoiler-slot-deflector aileron. The wing section loading, wing-panel loading, and chord-extension loading are described.
Air Force Tests of Sperry Messenger Model With Six Sets of Wings
From Summary: "The purpose of this test was to compare six well-known airfoils, the R.A.F 15, U.S.A. 5, U.S.A. 27, U.S.A. 35-B, Clark Y, and Gottingen 387, fitted to the Sperry Messenger model, at full scale Reynolds number as obtained in the variable density wind tunnel of the National Advisory Committee for Aeronautics; and to determine the scale effect on the model equipped with all the details of the actual airplane. The results show a large decrease in minimum drag coefficient upon increasing the Reynolds number from about one-twentieth scale to full scale. A comparison is made between the results of these tests and those obtained from tests made in this tunnel on airfoils alone."
Altitude Performance of a Turbojet Engine Using Pentaborane Fuel
Memorandum presenting a turbojet engine with a two-stage turbine operated with pentaborane fuel continuously for 11.5 minutes at a simulated altitude of 55,000 feet at a flight Mach number of 0.8. The engine incorporated an NACA combustor designed specifically for use with pentaborane fuel. Results regarding oxide formation and deposition, engine operating point, effect of oxide deposits on component performance, effect of oxide deposition on overall performance, and some operational comments are provided.
Altitude performance of a turbojet engine using pentaborane fuel
From Summary: "The primary objectives of the investigation reported herein were to determine the effect of this new combuster design on boric oxide deposition on engine parts and to determine the effect of boric oxide on the performance of multistage turbine. Pentaborance fuel (approx. 130 lb) was used in the engine performance evaluation reported herein. The data presented herein show the engine component and over-all performance deterioration with operation on pentaborane fuel".
Altitude-Wind-Tunnel Investigation of the 19B-2, 19B-8, and 19XB-1 Jet-Propulsion Engines 2 - Analysis of Turbine Performance of the 19B-8 Engine
"Performance characteristics of the turbine in the 19B-8 jet propulsion engine were determined from an investigation of the complete engine in the Cleveland altitude wind tunnel. The investigation covered a range of simulated altitudes from 5000 to 30,000 feet and flight Mach numbers from 0.05 to 0.46 for various tail-cone positions over the entire operable range of engine speeds. The characteristics of the turbine are presented as functions of the total-pressure ratio across the turbine and the turbine speed and the gas flow corrected to NACA standard atmospheric conditions at sea level" (p. 1).
Analysis and modification of theory for impact of seaplanes on water
From Summary: "An analysis of available theory on seaplane impact and a proposed modification thereto are presented. In previous methods the overall momentum of the float and virtual mass has been assumed to remain constant during the impact but the present analysis shows that this assumption is rigorously correct only when the resultant velocity of the float is normal to the keel."
Analysis of performance of four symmetrical-diagram-type subsonic inlet-stage axial-flow compressors
Report presenting an investigation of four axial-flow single-stage compressors with a hub-tip radius ratio of 0.5 with three objectives related to the ideal symmetrical-velocity-diagram design, the comparison of blade-element turning angle and loss data with cascade data, and the validity of the simplified radial-equilibrium equation. Results regarding the overall performance, blade-element performance, and radial equilibrium considerations are provided.
Analytical comparison of turbine-blade cooling systems designed for a turbojet engine operating at supersonic speed and high altitude 1: liquid-cooling systems
Report presenting an investigation of the influence of high-altitude supersonic flight on the operation and effectiveness of turbine-blade liquid-cooling systems for application in turbojet engines in guided missiles and in supersonic aircraft. The problems encountered in liquid-cooling systems were investigated with reference to several specific designs for alternate heat-rejection mediums.
Approximate Stress Analysis of Multistringer Beams With Shear Deformation of the Flanges
"The problem of the skin-stringer combinations used as axially loaded panels or as covers for box beams is considered from the point of view of the practical stress analyst. By a simple substitution the problem is reduced to the problem of the single-stringer structure, which has been treated in NACA Report no. 608. The method of making this substitution is essentially empirical; in order to justify it, comparisons are shown between calculations and strain-gage tests of three beams tested by the author and of one compression panel and three beams tested and reported elsewhere" (p. 469).
Blowing Over the Flaps and Wing Leading Edge of a Thin 49 Degree Swept Wing-Body-Tail Configuration in Combination With Leading-Edge Devices
Report presenting an investigation in the full-scale tunnel to determine the effects of the low-speed aerodynamic characteristics of blowing air over the trailing-edge flap of a large-scale wing-body-tail model. Results regarding half-span flaps and full-span flaps, pitching-moment and longitudinal trim characteristics, drag characteristics, lift-drag ratio, and lateral control are provided.
Calculated condenser performance for a steam turbine power plant for aircraft
Report presenting calculations to determine the effect of several operating conditions on the performance of condensers for steam-turbine power plants. The analysis covered a range of turbine-inlet pressures and turbine-outlet pressures for various condenser cooling-air pressure drops, flight speeds, and altitudes. Results regarding steam-cycle performance, effect of turbine-outlet pressure on condenser performance, effect of cooling-air pressure drop on condenser performance, effect of turbine-inlet temperature on condenser performance, and power-plant-weight estimates are provided.
Canard Hinge Moments and Longitudinal Stability of a 1/7-Scale Model of the Convair B-58 External Store in a Free-Flight Investigation at Mach Numbers From 0.94 to 2.58
Report presenting a longitudinal stability and control investigation of a model of the Convair B-58 external store over a range of Mach numbers. Normal force, chord force, and static and dynamic stability derivatives are provided. Abrupt pitching disturbances were created by step-function movements of the canard surface.
Canard Hinge Moments and Longitudinal Stability of a 1/7-Scale Model of the Convair B-58 External Store in a Free-Flight Investigation at Mach Numbers From 0.94 to 2.58: Coord. No. AF-204
Memorandum presenting a longitudinal stability and control investigation made over a range of Mach numbers of a scale model of the Convair B-58 external store. Normal force, chord force, and static and dynamic stability derivatives formed an important part of the results. Results regarding the hinge moments and longitudinal trim and force coefficients are also provided.
The characteristics of 78 related airfoil sections from tests in the variable-density wind tunnel
An investigation of a large group of related airfoils was made in the NACA variable-density wind tunnel at a large value of the Reynolds number. The tests were made to provide data that may be directly employed for a rational choice of the most suitable airfoil section for a given application. The variation of the aerodynamic characteristics with variations in thickness and mean-line form were systematically studied. (author).
Coking of JP-4 fuels in electrically heated metal tubes
A limited exploratory investigation of the rate of coking of four JP-4 fuels in electrically heated metal tubes was conducted in order to provide design information for fuel prevaporizers for turbojet-engine combustors. The fuels tested included two production and two minimum-quality JP-4 type fuels. The heating tube was operated at fuel pressures of approximately 500, 400, and 50 pounds per square inch. The operating fuel temperature was varied between approximately 600 degrees and 1200 degrees F.
Comparison Between Analytical and Wind-Tunnel Results on Flutter of Several Low-Aspect-Ratio, High-Density, Unswept Wings at High Subsonic Speeds and Zero Angle of Attack
Memorandum presenting experimental flutter Mach numbers for several solid, thin, rectangular cantilever wings with uniform section properties, low aspect ratio, and high relative density estimated from the results of previous tests at zero angle of attack. The experimental values are considered estimates, rather than determinations, in the high subsonic speed range because in that range the amplitude criterion was necessarily arbitrary. Results regarding conservatism of standard analysis relative to the experiment, closeness of analytical and experimental results, and interpretation of the analytical and experimental uncertainties are provided.
Comparison of Measured Efficiencies of Nine Turbine Designs with Efficiencies Predicted by Two Empirical Methods
Empirical methods of Ainley and Kochendorfer and Nettles were used to predict performances of nine turbine designs. Measured and predicted performances were compared. Appropriate values of blade-loss parameter were determined for the method of Kochendorfer and Nettles. The measured design-point efficiencies were lower than predicted by as much as 0.09 (Ainley and 0.07 (Kochendorfer and Nettles).
Component Performance Investigation of J71 Type II Turbines 3 - Overall Performance of J71 Type IIA Turbine
"The over-all component performance characteristics of the J71 Type IIA three-stage turbine were experimentally determined over a range of speed and over-all turbine total-pressure ratio at inlet-air conditions af 35 inches of mercury absolute and 700 deg. R. The results are compared with those obtained for the J71 Type IIF turbine, which was previously investigated, the two turbines being designed for the same engine application. Geometrically the two turbines were much alike, having the same variation of annular flow area and the same number of blades for corresponding stator and rotor rows" (p. 1).
Compressible-Flow Solutions for the Actuator Disk
Report presenting generalized solutions for the actuator disk in subsonic compressible flow and the compressible- and incompressible-flow phenomena are compared. Results regarding the ideal solutions of flow variables, effect of additional losses, and actuator disks in tandem are provided. Large differences in flow variables were observed across the actuator disk.
Coolant-Flow Calibrations of Three Simulated Porous Gas-Turbine Blades
"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" (p. 1).
Cooling of Gas Turbines, 2, Effectiveness of Rim Cooling of Blades
An analysis of rim cooling, which cools the blade by condition alone, was conducted. Gas temperatures ranged from 1300 degrees to 1900 degrees F and rim temperatures from 0 degrees to 1000 degrees F below gas temperatures. Results show that gas temperature increases up to 200 degrees F are permissible provided that the blades are cooled by 400 degrees to 500 degrees F below the gas temperature. Relatively small amounts of blade cooling, at constant gas temperature, give large increases in blade life. Dependence of rim cooling on heat-transfer coefficient, blade dimensions, and thermal conductivity is determined by a single parameter.
Cooling of gas-turbines 7: effectiveness of air cooling of hollow turbine blades with inserts
Report presenting an analytical investigation to determine primarily the reduction in cooling-air requirement and the increase in effective gas temperature for the same quantity of cooling air resulting from the use of an insert in the cooling-air passage of a hollow air-cooled turbine blade.
Cooling tests of a single-row radial engine with several NACA cowlings
The cooling of a single-row radial air-cooled engine using several cowling arrangements has been studied in the NACA 20-foot wind tunnel. The results show the effect of the propeller and several cowling arrangements on cooling for various values of the indicated horsepower in the climb condition. A table giving comparative performance of the various cowling arrangements is presented. The dependence of temperature on indicated horsepower and pressure drop across the baffles is shown by charts. Other charts show the limiting indicated horsepower against the pressure drop across the engine and the heat dissipated at various values of the indicated horsepower.
Correction of Temperatures of Air-Cooled Engine Cylinders for Variation in Engine and Cooling Conditions
"Factors are obtained from semiempirical equations for correcting engine-cylinder temperatures for variation in important engine and cooling conditions. The variation of engine temperatures with atmospheric temperature is treated in detail, and correction factors are obtained for various flight and test conditions, such as climb at constant indicated air speed, level flight, ground running, take-off, constant speed of cooling air, and constant mass flow of cooling air. Seven conventional air-cooled engine cylinders enclosed in jackets and cooled by a blower were tested to determine the effect of cooling-air temperature and carburetor-air temperature on cylinder temperatures" (p. 49).
Correlation of Physical Properties With Molecular Structure for Some Dicyclic Hydrocarbons Having High Thermal-Energy Release Per Unit Volume
"As part of a program to study the correlation between molecular structure and physical properties of high-density hydrocarbons, the net heats of combustion, melting points, boiling points, densities, and kinematic viscosities of some hydrocarbons in the 2-n-alkylbiphenyl, 1,1-diphenylalkane, diphenylalkane, 1,1-dicyclohexylalkane, and dicyclohexylalkane series are presented" (p. 55).
Critical Stress of Thin-Walled Cylinders in Axial Compression
Empirical design curves are presented for the critical stress of thin-wall cylinders loaded in axial compression. These curves are plotted in terms of the nondimensional parameters of small-deflection theory and are compared with theoretical curves derived for the buckling of cylinders with simply supported and clamped edges. An empirical equation is given for the buckling of cylinders having a length-radius ratio greater than about 0.75.
A description of the Ames 2- by 2-foot transonic wind tunnel and preliminary evaluation of wall interference
Report presenting a description of the Ames 2- by 2-foot transonic wind tunnel, its uses in testing, and a preliminary evaluation of the wall interference in the tunnel.
Determination of Coupled Modes and Frequencies of Swept Wings by Use of Power Series
"A solution is presented for the coupled modes and frequencies of swept wings mounted on a fuselage. The energy method is used in conjunction with power series to obtain the characteristic equations for both symmetrical and asymmetrical vibration. A numerical example which is susceptible to exact solution is presented, and the results for the exact solution and the solution presented in this paper show excellent agreement" (p. 1).
Ditching Tests of a 1/18-Scale Model of the Lockheed Constellation Airplane
"Tests were made of a 1/18-scale dynamically similar model of the Lockheed Constellation airplane to investigate its ditching characteristics and proper ditching technique. Scale-strength bottoms were used to reproduce probable damage to the fuselage. The model was landed in calm water at the Langley tank no. 2 monorail. Various landing attitudes, speeds, and fuselage configurations were simulated" (p. 1).
Ditching Tests of a 1/20-Scale Model of the Northrop B-35 Airplane
"Tests of a 1/20-scale dynamically similar model of the Northrop B-35 airplane were made to study its ditching characteristics. The model was ditched in calm water at the Langley tank no. 2 monorail. Various landing attitudes, speeds,and conditions of damage were simulated during the investigation. The ditching characteristics were determined by visual observation and from motion-picture records and time-history acceleration records" (p. 1).
Drag Measurements of a 34 Degree Swept-Forward and Swept-Back NACA 65-009 Airfoil of Aspect Ratio 2.7 as Determined by Flight Tests at Supersonic Speeds
Report presenting the results of flight testing to determine the zero-lift drag of an NACA 65-009 airfoil at a specified aspect ratio. The results are compared to previous testing of unswept and swept-back arrangements. The swept-forward and swept-back airfoils were found to produce lower values of zero-drag lift than the unswept airfoil.
Drag of Wings With End Plates
"In this report a formula for calculating the induced drag of multiplanes with end plates is derived. The frictional drag of the end plates are used, is sufficiently large to increase the efficiency of the wing. Curves showing the reduction of drag for monoplanes and biplanes are constructed; the influence of gap-chord ratio, aspect ratio, and height of end plate are determined for typical cases. The method of obtaining the reduction of drag for a multiplane is described" (p. 253).
Dynamic and flight tests on rubber-cord and oleo-rubber-disk landing gears for an F6C-4 airplane
The investigation described in this report was conducted for the purpose of comparing an oleo-rubber-disk and a rubber-cord landing gear, built for use on an F6C-4 airplane. The investigation consisted of drop tests under various loading conditions and flight tests on an F6C-4 airplane. In the drop tests the total work done on each gear and the work done on each of the shock-absorbing units were determined. For both drop tests and flight tests the maximum loads and accelerations were determined. The comparative results showed that the oleo gear was slightly superior in reducing the ordinary landing shocks, that it had a greater capacity for work, and that it was very superior in the reduction of the rebound. The results further showed that for drops comparable to very severe landings, the rubber-cord gear was potentially more effective as a shock-reducing mechanism. However, due to the construction of this chassis, which limited the maximum elongation of the cords, this gear was incapable of withstanding as severe tests as the oleo gear. The action of the oleo gear was greatly inferior to the action of an ideal gear. The maximum accelerations encountered during the flight tests for severe landings were 3.64g for the rubber-cord gear and 2.27g for the oleo gear. These were less than those experienced in free drops of 7 inches on either gear.
Dynamic Response of Turbine-Blade Temperature to Exhaust-Gas Temperature for Gas-Turbine Engines
"The frequency of blade temperature to exhaust gas temperature is presented for two locations in the blade and at several operating conditions. The frequency response was determined by Fourier analysis of transient data. Two analytical methods are presented, and results are compared with experimental data. Dynamic response of turbine-blade temperature to exhaust-gas temperature exhibited the form of an approximate first-order lag" (p. 1).
Effect of a leading-edge flap upon the lift, drag, and pitching moment of an airplane employing a thin, unswept wing
Report presenting the effects of deflecting full-span, constant-chord, leading-edge flaps with round or sharp leading edges on the lift, drag, and pitching-moment characteristics of a model of an interceptor-type aircraft at supersonic and subsonic speeds.
Effect of a pilot's canopy on the drag of an NACA RM-2 drag research model in flight at transonic and supersonic speeds
Report presenting data from two experiments. One used the NACA RM-2 drag research model equipped with a pilot's canopy to determine the effect on aerodynamics. The other was conducted with the same configuration and returned similar results.
Effect of Design Over-All Compressor Pressure Ratio Division on Acceleration Characteristics of Three Hypothetical Two-Spool Turbojet Engines
The engines, each with a compressor overall total-pressure ratio of 12 and a design inner-turbine-inlet temperature of 2500 degrees R, were investigated at static sea-level conditions to determine the effect on transient performance of varying the desitn pressure ratio divisions 2-6, 3-4, and 4-3 between the outer and inner compressors. The transient considered was an acceleration from 40 to 100 percent design thrust. When the outer compressor of each engine reached design speed, the inner compressors were overspeeding, the maximum being only 1.7 over design mechanical speed. Acceleration times for the three engines were equal.
Effect of initial mixture temperature on flame speed of methane-air, propane-air, and ethylene-air mixtures
"Flame speeds based on the outer edge of the shadow cast by the laminar Bunsen cone were determined as functions of composition for methane-air mixtures at initial mixture temperatures ranging from -132 degrees to 342 degrees c and for propane-air and ethylene-air mixtures at initial mixture temperatures ranging from -73 degrees to 344 degrees c. The data showed that maximum flame speed increased with temperature at an increasing rate. The percentage change in flame speed with change in initial temperature for the three fuels followed the decreasing order, methane, propane, and ethylene" (p. 105).
The effect of lateral controls in producing motion of an airplane as computed from wind-tunnel data
This report presents the results of an analytical study of the lateral controllability of an airplane in which both the static rolling and yawing moments supplied by the controls and the reactions due to the inherent stability of the airplane have been taken into account. The investigation was undertaken partly for the purpose of coordinating the results of a long series of wind-tunnel investigations with phenomena observed in flight tests; for this reason a hypothetical average airplane, embodying the essential characteristics of both wind-tunnel models and the full-size test airplanes, was assumed for the study.
The effect of leading-edge extensions on the longitudinal characteristics at Mach numbers up to 0.92 of a wing-fuselage-tail combination having a 40 degree sweptback wing with NACA 64A thickness distribution
Report presenting a wind-tunnel investigation to determine the effects of leading-edge extensions on the longitudinal characteristics of a wing-fuselage and wing-fuselage-tail combination with a wing of 40 degrees sweepback and NACA 64A thickness distribution.
Effect of Mach Number on Boundary-Layer Transition in the Presence of Pressure Rise and Surface Roughness on an Ogive-Cylinder Body with Cold Wall Conditions
Memorandum presenting an investigation of the effect of Mach number variation from 1.8 to 7.4 on boundary-layer transition on a slender fin-stabilized ogive-cylinder body in free flight at a constant length Reynolds number of 13.8 million. Results showed that increasing Mach number had a very favorable effect of increasing the extent of the laminar boundary layer for a given surface roughness. Results regarding Mach number and surface roughness, effects of pressure rise, and long laminar runs are provided.
The effect of mass distribution on the lateral stability and control characteristics of an airplane as determined by tests of a model in the free-flight tunnel
The effects of mass distribution on lateral stability and control characteristics of an airplane have been determined by flight tests of a model in the NACA free-flight tunnel. In the investigation, the rolling and yawing moments of inertia were increased from normal values to values up to five times normal. For each moment-of-inertia condition, combinations of dihedral and vertical-tail area representing a variety of airplane configurations were tested. The results of the flight tests of the model were correlated with calculated stability and control characteristics and, in general, good agreement was obtained.
The Effect of Modified Baffles and Auxiliary-Cooling Ducts on the Cooling of a Double-Row Radial Engine
Report discussing testing to determine the cooling effect of modified baffles and auxiliary-cooling ducts on the rear-row cylinders of a double-row radial engine. The modified baffles were found to reduce the temperatures of the exhaust-valve seats, but did not have an effect on the valve-guide temperatures. The auxiliary-cooling ducts reduced temperatures of the exhaust-valve seats and rear spark plug gaskets.
Effect of ram-jet pressure pulsations on supersonic-diffuser performance
Experimental study of effects of combustion roughness and controlled mechanical oscillations on diffuser operation was conducted on an 8-inch ram jet at Mach number 1.87. Within experimental accuracy, the optimum mean combustion-chamber static pressure occurred when the maximum instantaneous static pressure equalled the optimum steady-flow value and the corresponding decrement in optimum mean static pressure was equal to one-half the total amplitude of the pressure pulsations. A marked attenuation of amplitude of cold-buzz pressure fluctuations was effected over limited range of subcritical diffuser operation by means of properly tuned rotating disk located in combustion chamber.
The effect of rate of change of angle of attack on the maximum lift coefficient of a pursuit airplane
Report presenting an investigation of the effect of the rate of change of angle of attack on the maximum lift coefficient of a pursuit airplane equipped with a low-drag-type wing in stalls of varying abruptness over a range of Mach and Reynolds numbers. Maximum lift coefficients were found to increase linearly with increasing rate of change of angle of attack per chord length of travel up to the maximum rate attained in the tests.
Back to Top of Screen