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Accelerations in Transport-Airplane Crashes
From Introduction: "A study of crash-impact survival in light airplanes is reported in references 1 and 2. A similar study for fighter airplanes is reported in reference 3. This report discusses crash-impact survival in transport airplanes."
Acoustic, thrust, and drag characteristics of several full-scale noise suppressors for turbojet engines
From Introduction: " Considerable analytical and experimental research has been done to find means of reducing the noise levels of the turbojet transports. Noise levels can be decreased by engine redesign to reduce the jet-exit velocity (ref. 1), proper flight-climb techniques (ref. 2), and the use of noise-suppression exhaust nozzles (refs. 3 to 5). The present report is concerned with the last method."
Aerodynamic Effects Caused by Icing of an Unswept NACA 65A004 Airfoil
From Summary: "The effects of ice formations on the section lift, drag, and pitching-moment coefficients of an unswept NACA 65A004 airfoil section of 6-foot chord were studied.. The magnitude of the aerodynamic penalties was primarily a function of the shape and size of the ice formation near the leading edge of the airfoil. The exact size and shape of the ice formations were determined photographically and found to be complex functions of the operating and icing conditions."
Analysis of harmonic forces produced at hub by imbalances in helicopter rotor blades
From Introduction: "First, an analysis of loads transmitted to the hub by balanced blades will be given. In the second section, the additional loads transmitted to the hub in a direction normal to the plane of rotation of the blades by imbalances in a rotor are derived. In the entire analysis, the results are given in terms of the forces transmitted to the hub by a single rotating helicopter blade in flight, and these are regarded as known or given."
An Analysis of Ramjet Engines Using Supersonic Combustion
From Introduction: "The concept of supersonic combustion is by no means new, although little work appears to have been published on the subject. For example, an analysis of supersonic combustion to provide lift under a wing is given in reference 1. Reference 2 discusses applications to hypersonic ramjets being studied at the University of Michigan."
Analysis of stresses and deflections in a disk subjected to gyroscopic forces
From Summary: "Results are presented in dimensionless form suitable for design purposes. The method for solving the problem of a disk of variable thickness with a temperature gradient is also presented."
Analysis of the Creep Behavior of a Square Plate Loaded in Edge Compression
From Introduction: "In reference 1 results of creep tests and empirical method for predicting collapse times are presented for plates loaded in compression on two opposite edges and with the remaining edges unloaded and supported in V-groove fixtures. Other approximate methods for handling plates having types of edge support are suggested in reference 2; however, experimental verification for these methods is quite limited. In reference 3 an analysis based on small-deflection theory is made of the creep deflection of a simply supported plate composed of a linear viscoelastic material - that is, a material in which the stress and strain and their appropriate time derivatives are related in a linear fashion."
An Analysis of the Optimization of a Beam Rider Missile System
"The paper begins with a discussion of the optimum system and the corresponding minimum error. A brief discussion of this miss as a function of the parameters which determine it is then given" (p. 2).
An analysis of the turbulent boundary-layer characteristics on a flat plate with distributed light-gas injection
From Introduction: "The present paper is concerned with a transpiration cooling system in which the coolant passes through the surface it is protecting before entering the surrounding boundary layer. Analyses and experiments have been performed to determine the effect of distributed air transportation through flat surfaces over which air flows in turbulent boundary layer (refs. 2, 3, and 4)."
Analysis of Turbulent Flow and Heat Transfer in Noncircular Passages
From Introduction: "In reference 1, wall temperature distributions for turbulent flow in rectangular and triangular ducts were calculated by using experimental velocity distributions and average heat-transfer coefficients, together with assumed similarity of the wall heat-transfer and wall shear-stress variations; no attempt was made to calculate either the heat-transfer coefficients or the velocity and temperature distributions in the fluid field. Some calculations of velocity and shear-stress distributions in corners are reported in reference 2."
Analysis of Turbulent Flow and Heat Transfer on a Flat Plate at High Mach Numbers With Variable Fluid Properties
From Introduction: "In the turbulent case, however, the results of the various analyses disagree markedly because of the different assumptions made by various authors. These analyses are reviewed in references 1 to 3. The analysis is extended to flow and heat transfer in a boundary layer at high Mach numbers in this paper. (Some preliminary results were presented in ref. 11.)"
Analytical and Experimental Investigation of Aerodynamic Forces and Moments on Low-Aspect-Ratio Wings Undergoing Flapping Oscillations
"Aerodynamic forces and moments associated with flapping oscillations of finite wings at low speeds are considered. A comparison of theoretical and experimental results is made for a rectangular wing of aspect ratio 2. Calculated results are also given for three tapered wings of aspect ratio 3 with varying amounts of sweepback" (p. 1).
Analytical and Experimental Investigation of Temperature Recovery Factors for Fully Developed Flow of Air in a Tube
Note presenting an analysis made for predicting temperature recovery factors for fully developed flow in a tube. Most of the attention was confined to turbulent flow. Both analytical and experimental results are provided for the air flow.
Analytical investigation of acceleration restriction in a fighter airplane with an automatic control system
From Introduction: "In the present report, consideration is given to certain features intended to improve the accleration-limiting characteristics of a normal-accleration control system."
Analytical relation for wake momentum thickness and diffusion ratio for low-speed compressor
From Introduction: "The present report presents the derivation of a simple equation for blade-wake mometum thickness as a function of suction-surface diffusion ratio based on the one-dimensional boundary-layer mometum equation in conjunction with simplifying approximations."
An analytical study of turbulent and molecular mixing in rocket combustion
From Introduction: "The many physical processes which occur simultaneously in rocket combustion make the entire process extremely complex (ref. 1). The combustion chamber length required for evaporation of liquid-propellant sprays has already been studied (refs. 2, 3, and 4)."
Application of a high-temperature static strain gage to the measurement of thermal stresses in a turbine stator vane
From Introduction: "This report describes the high-temperature static strain gage and presents the results obtained in a determination of the thermal stresses in a turbine stator vane resulting from the temperature distribution obtained under steady-state conditions at rated speed and temperature of the engine."
Application of statistical theory to beam-rider guidance in the presence of noise 2: modified Wiener filter theory
Report presenting a study of the application of Newton's modification of the Wiener filter theory to optimize a beam-rider guidance system operating in the presence of glint noise.
An Approach to the Problem of Estimating Severe and Repeated Gust Loads for Missile Operations
Note presenting an analysis of available airplane measurements of vertical gust velocity in order to arrive at a simple description of the frequency and intensity of gust velocities experienced by airplanes in operations. For the purpose of application to missile operations, the results obtained are modified to eliminate the effects of storm-avoidance procedures normally followed in airplane operations.
An approximate analytical method for studying entry into planetary atmospheres
Report presenting a single, ordinary, nonlinear differential equation of second order that can be used for determining entry into an exponential planetary atmosphere. The reduced equation includes various terms, some of which represent the gravity force, the centrifugal acceleration, and the lift force. A number of solutions for lifting and nonlifting vehicles entering at various initial angles are obtained from the complete nonlinear equation.
Approximate method for calculating motions in angles of attack and sideslip due to step pitching- and yawing-moment inputs during steady roll
Report presenting an extension of a method for calculating motions in angles of attack and sideslip resulting from a trim angle of attack and steady rolling velocity to the condition of pitching- and yawing-moment inputs. The resulting formulas are intended primarily for rolling-velocity conditions in which rolling divergence is not encountered.
Approximate Method for Calculation of Laminar Boundary Layer With Heat Transfer on a Cone at Large Angle of Attack in Supersonic Flow
Note presenting the use of an integral technique to reduce the laminar boundary-layer equations on the windward generator of the plane of symmetry to a set of simultaneous algebraic equations. The method enables the skin friction coefficients and Stanton number to be calculated in a much shorter time than was needed to obtain exact numerical solutions from the boundary-layer equations.
An Approximate Method for Design or Analysis of Two-Dimensional Subsonic-Flow Passages
Note presenting a method for the design and analysis of two-dimensional subsonic-flow passages with isentropic nonviscous flow. The method is based on the relation between the pressure change across a stream tube and the centrifugal force resulting from the curvature of the flow. In an example, the method was applied to the design of an expanding elbow at each of two Mach numbers.
Approximate solutions of a class of similarity equations for three-dimensional, laminar, incompressible boundary-layer flows
Report presenting an analysis for obtaining approximate solutions of the similarity equations for three-dimensional laminar-boundary-layer flows over a flat surface under main-flow streamlines that are translates and representable as infinite series expansions.
Approximations for the thermodynamic and transport properties of high-temperature air
Report presenting the thermodynamic and transport properties of high-temperature air in closed form starting from approximate partition functions for the major components in air and neglecting all minor components. The compressibility, energy, entropy, specific heats, speed of sound, coefficients of viscosity and thermal conductivity, and Prandtl numbers for air are provided for a range of temperatures and pressures.
A Body Modification to Reduce Drag Due to Wedge Angle of Wing with Unswept Trailing Edge
From Summary: "Ward's slender-body-theory formula for zero-lift drag contains three integrals plus a base-drag term. Two of these integral terms depend only upon the cross-sectional area distribution of the body. The third integral term depends only upon the body shape and axial slopes at the base of the body. This term is neglected in the transonic area rule because in many cases it is zero; however, there are also many cases in which it is not zero. This paper examines the term for the possibility of drag reduction for a particular case."
Boundary-Induced Downwash Due to Lift in a Two-Dimensional Slotted Wind Tunnel
Note presenting a solution obtained for the complete tunnel-interference flow for a lifting vortex in a two-dimensional slotted tunnel. Curves are presented for the longitudinal distribution of tunnel-induced downwash angle for various values of boundary openness parameter and various heights of the vortex above the tunnel center line.
Boundary-layer stability diagrams for electrically conducting fluids in the presence of a magnetic field
From Summary: "The effectiveness of a magnetic field in stabilizing the laminar flow of an incompressible, electrically conducting fluid is studied. The neutral stability curves pertaining to a two-dimensional sinusoidal disturbance are presented for flow over a semi-infinite flat plate in the presence of either a coplanar or transverse magnetic field and for channel flow in the presence of a coplanar or transverse magnetic field and for channel flow in the presence of a coplanar magnetic field. As is to be expected, the magnetic field stabilizes the flow unless the velocity profile is distorted by the magnetic field to an inherently unstable shape."
Boundary-layer transition on an open-nose cone at Mach 3.1
Report presenting comparison of transition locations for an open-nose cone, a conventional sharp cone, and a hollow cylinder showed that transition locations on the open-nose cone and hollow cylinder were identical but differed from the sharp cone. Bluntness effects on the open-nose cone were quite similar to those observed on the hollow cylinder.
Central Automatic Data Processing System
A series of papers describing a system that will automatically record as many as 300 pressures, 200 voltages, and 24 frequencies in as little as 30 seconds to an accuracy of 0.15 percent or better of full-scale range. The information is able to be used in any high-speed, general-purpose digital computer. The computer will accept the encoded data produced by the recording system and automatically calibrates it, takes averages, forms ratios, and does terminal calculations such as mass flow, momentum, distortion numbers, drag coefficients, thrust, specific fuel consumption, and efficiency.
Charts Relating the Compressive and Shear Buckling Stresses of Longitudinally Supported Plates to the Effective Deflectional Stiffness
"A stability analysis is made of long flat rectangular plates subjected to both shear and compressive loads. The edges of the plates are taken to be simply supported and the plates are supported along one or two intermediate longitudinal lines by lines of deflectional springs (elastic line supports). The results of the analysis are presented in the form of charts that are useful in the determination of the buckling load of plates stiffened by stringers or webs" (p. 1).
Comparison of hydrodynamic-impact acceleration and response for systems with single and with multiple elastic modes
Report presenting hydrodynamic impact testing made with a multimode elastic model consisting of a rigid prismatic float and a flexible wing and a comparison with similar experimental results for a single-mode system and with theoretical solutions. Testing was conducted in smooth water at two fixed trims and two flight-path angles over a range of velocities. Results regarding accelerations, time histories, oscillatory accelerations, elastic-body acceleration data, and rigid-body acceleration data are provided.
Comparison of shock-expansion theory with experiment for the lift, drag, and pitching-moment characteristics of two wing-body combinations at M=5.0
Report presenting lift, drag, and pitching-moment coefficients for two wing-body combinations as determined from tests at Mach number 5.0 and angles of attack up to 9 degrees. The test models consisted of small thin wings mounted on a body composed of a fineness-ratio-3 ogival nose and a fineness-ratio-2 cylindrical afterbody.
A comparison of two methods for calculating transient temperatures for thick walls
Report presenting a comparison of two different methods of calculating transient temperatures for thick walls with arbitrary variation of heat-transfer coefficient and adiabatic-wall temperature.
Compilation of information on the transonic attachment of flows at the leading edges of airfoils
Schlieren photographs have been compiled of the two-dimensional flow at transonic speeds past 37 airfoils. These airfoils have variously shaped profiles, and some are related in thickness and camber. The data for these airfoils were analyzed to provide basic information on the flow changes involved and to determine factors affecting transonic-flow attachment, which is a transition from separated to unseparated flow at the leading edges of two-dimensional airfoils at fixed angles as the subsonic Mach number is increased.
Composition and thermodynamic properties of air in chemical equilibrium
"Charts have been prepared relating the thermodynamic properties of air in chemical equilibrium for temperatures to 15,000 degrees k and for pressures 10(-5) to 10 (plus 4) atmospheres. Also included are charts showing the composition of air, the isentropic exponent, and the speed of sound. These charts are based on thermodynamic data calculated by the National Bureau of Standards" (p. 1).
Compressible Laminar Flow and Heat Transfer About a Rotating Isothermal Disk
Note presenting a reexamination of the flow and heat transfer about a rotating isothermal disk to include the effects of compressibility and property variations. Results regarding velocities, temperatures, heat transfer, and skin friction and torque, are provided.
Compressive Strength and Creep of 17-7 PH Stainless-Steel Plates at Elevated Temperatures
Note presenting compressive strength test results from room temperature to 1000 degrees Fahrneheit and compressive creep test results from 700 to 1000 degrees Fahrenheit for plates of 17-7 PH stainless steel, Condition TH 1050, which were edge-supported in V-groove fixtures. The combinations of average stress, temperature, and time that produce given amounts of creep strain or failure are shown on master curves which facilitate interpolation of the test results.
Contribution of the wing panels to the forces and moments of supersonic wing-body combinations at combined angles
Report presenting a wind-tunnel investigation at Mach number 1.96 to determine the normal forces, pitching moments, and rolling moments contributed by each wing panel of a cruciform-wing and body combination over a wide range of combined angles of pitch and roll. The wings were triangular of aspect ratio 2 and the body was an ogive-cylinder combination. Results regarding individual panels and panel combinations are provided.
A Cooled-Gas Pyrometer for Use in High-Temperature Gas Streams
Report presenting a description of an immersion-type pyrometer that utilizes the controlled cooling of a continuously aspirated sample of the gas whose temperature is to be measured. Results regarding both the preliminary and final testing with this device are provided.
Correlations Among Ice Measurements, Impingement Rates Icing Conditions, and Drag Coefficients for Unswept NACA 65A004 Airfoil
"An empirical relation has been obtained by which the change in drag coefficient caused by ice formations on an unswept NACA 65A004 airfoil section can be determined from the following icing and operating conditions: icing time, airspeed, air total temperature, liquid-water content, cloud droplet impingement efficiencies, airfoil chord length, and angles of attack. The correlation was obtained by use of measured ice heights and ice angles. These measurements were obtained from a variety of ice formations, which were carefully photographed, cross-sectioned, and weighed" (p. 1).
Corrosion Resistance of Nickel Alloys in Molten Sodium Hydroxide
Note presenting a study of the corrosion resistance of 11 nickel-base compositions to molten sodium hydroxide at 1500 and 1700 degrees Fahrenheit in order to find a container material for the caustic at these temperatures. Results are provided for the solid-solution alloys, nickel with mechanically dispersed second phase materials, and the precipitation-hardened alloy.
Creep of Aluminum-Copper Alloys During Age Hardening
Note presenting a study of the interrelation of aging during creep and of creep during aging in polycrystalline aluminum alloys containing 1 to 4 percent copper. Experimental procedures included interrupted creep tests, tensile tests of crept specimens, quantitative metallographic determination of the percent precipitation during creep, hardness measurements on unstressed and stressed aged alloys, X-ray studies of deformation in the crystalline lattice, and microscopic examination of the surface-deformation markings.
Cumulative Fatigue Damage at Elevated Temperature
"A study of cumulative fatigue damage at elevated temperatures was conducted using heat-treated SAE 4130 alloy steel. The S-N curves at room temperature, 400 degrees Fahrenheit, and 800 degrees Fahrenheit were obtained from rotating-beam fatigue tests. Two-step, three-step, and five-step cumulative-damage fatigue tests were conducted on rotating-beam fatigue specimens at room temperature, 400 degrees Fahrenheit, and 800 degrees Fahrenheit. The results of the cumulative-damage tests are compared with those of a theoretical analysis" (p. 1).
Discharge coefficients for combustor-liner air-entry holes 2: flush rectangular holes, step louvers, and scoops
Experimental discharge coefficients for various types of combustor-liner air-entry holes are presented as a function of a dimensionless flow parameter. In general, scoops and step louvers have higher discharge coefficients and wider flow ranges than flush holes. The effects of size or shape of a given type of hole are small. The proximity of multiple flush holes or the wall inclination of a convergent duct has a negligible effect on discharge coefficient.
Discrete Potential Theory for Two-Dimensional Laplace and Poisson Difference Equations
Note presenting a method for solving problems associated with Laplace and Poisson equations which, in general, requires considerably fewer equations than the usual methods and which gives a convergent solution by the method of successive approximations.
Drag Minimization for Wings in Supersonic Flow, With Various Constraints
Report presenting a study of the minimization of inviscid fluid drag for thin aerodynamic shapes subject to imposed constraints on lift, pitching moment, base area, or volume. The problem is transformed to one or determining a two-dimensional potential flow satisfying either Laplace's or Poisson's equations with boundary values fixed by the imposed conditions.
Drop-size distributions for impinging-jet breakup in airstreams simulating the velocity conditions in rocket combustors
Report presenting drop-size-distribution data obtained for heptane sprays produced by pairs of impinging jets in airstreams over ranges of orifice diameter, liquid-jet velocity, and velocity difference between the airstream and the liquid jet.
Droplet Impingement and Ingestion by Supersonic Nose Inlet in Subsonic Tunnel Conditions
"The amount of water in cloud droplet form ingested by a full-scale supersonic nose inlet with conical centerbody was measured in the NACA Lewis icing tunnel. Local and total water impingement rates on the cowl and centerbody surfaces were also obtained. All measurements were made with a dye-tracer technique" (p. 1).
Dynamic stability of vehicles traversing ascending or descending paths through the atmosphere
From Summary: "An analysis is given of the oscillatory motions of vehicles which traverse ascending and descending paths through the atmosphere at high speed. The specific case of a skip path is examined in detail, and this leads to a form of solution for the oscillatory motion which should recur over any trajectory. The distinguishing feature of this form is the appearance of the Bessel rather than the trigonometric function as the characteristic mode of oscillation."
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