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Prediction of flame velocities of hydrocarbon flames (open access)

Prediction of flame velocities of hydrocarbon flames

The laminar-flame-velocity data previously reported by the Lewis Laboratory are surveyed with respect to the correspondence between experimental flame velocities and values predicted by semitheoretical and empirical methods. The combustible mixture variables covered are hydrocarbon structure (56 hydrocarbons), equivalence ratio of fuel-air mixture, mole fraction of oxygen in the primary oxygen-nitrogen mixture (0.17 to 0.50), and initial mixture temperature (200 degrees to 615 degrees k). The semitheoretical method of prediction considered are based on three approximate theoretical equations for flame velocity: the Semenov equation, the Tanford-Pease equation, and the Manson equation.
Date: January 2, 1953
Creator: Dugger, Gordon L. & Simon, Dorothy M.
System: The UNT Digital Library
Estimation of the Maximum Angle of Sideslip for Determination of Vertical-Tail Loads in Rolling Maneuvers (open access)

Estimation of the Maximum Angle of Sideslip for Determination of Vertical-Tail Loads in Rolling Maneuvers

Report includes the National Advisory Committee for Aeronautics Technical Reports 1135 through 1157. Recent experiences have indicated that angles of sideslip in rolling maneuvers may be critical in the design of vertical tails for current research airplanes having weight distributed mainly along the fuselage. Previous investigations have indicated the seriousness of the problem for the World War II type of airplane. This report presents some preliminary calculations for airplanes of current design, particularly with weight distributed primarily along the fuselage.
Date: 1953
Creator: Stone, Ralph W., Jr.
System: The UNT Digital Library
Charts and approximate formulas for the estimation of aeroelastic effects on the loading of swept and unswept wings (open access)

Charts and approximate formulas for the estimation of aeroelastic effects on the loading of swept and unswept wings

Charts and approximate formulas are presented for the estimation of aeroelastic effects on the spanwise lift distribution, lift-curve slope, aerodynamic center, and damping in roll of swept and unswept wings at subsonic and supersonic speeds. Some design considerations brought out by the results of this report are discussed.
Date: 1953
Creator: Diederich, Franklin W. & Foss, Kenneth A.
System: The UNT Digital Library
Charts and approximate formulas for the estimation of aeroelastic effects of the lateral control of swept and unswept wings (open access)

Charts and approximate formulas for the estimation of aeroelastic effects of the lateral control of swept and unswept wings

Charts and approximate formulas are presented for the estimation of static aeroelastic effects on the spanwise lift distribution, rolling-moment coefficient, and rate of roll due to the deflection of ailerons on swept and unswept wings at subsonic and supersonic speeds. Some design considerations brought out by the results of this report are discussed. This report treats the lateral-control case in a manner similar to that employed in NACA Report 1140 for the symmetric-flight case, and is intended to be used in conjunction with NACA Report 1140 and the charts and formulas presented therein.
Date: 1953
Creator: Foss, Kenneth A. & Diederich, Franklin W.
System: The UNT Digital Library
Aerodynamic Characteristics of a Refined Deep-Step Planing-Tail Flying-Boat Hull with Various Forebody and Afterbody Shapes (open access)

Aerodynamic Characteristics of a Refined Deep-Step Planing-Tail Flying-Boat Hull with Various Forebody and Afterbody Shapes

From Summary: "An investigation was made in the Langley 300 mph 7-by 10-foot tunnel to determine the aerodynamic characteristics of a refined deep-step planing-tail hull with various forebody and afterbody shapes. For comparison, tests were made on a streamline body simulating the fuselage of a modern transport airplane. The results of the tests, which include the interference effects of a 21-percent-thick support wing, indicated that for corresponding configurations the hull models incorporating a forebody with a length-beam ratio of 7 had lower minimum drag coefficients than the hull models incorporating a forebody with a length-beam ratio of 5. Longitudinal and lateral stability was generally about the same for all hull models tested and about the same as that of a conventional hull."
Date: 1953
Creator: Riebe, John M. & Naeseth, Rodger L.
System: The UNT Digital Library
Aerodynamic forces and loadings on symmetrical circular-arc airfoils with plain leading-edge and plain trailing-edge flaps (open access)

Aerodynamic forces and loadings on symmetrical circular-arc airfoils with plain leading-edge and plain trailing-edge flaps

From Summary: "An investigation has been made in the Langley two-dimensional low-turbulence tunnel and in the Langley two-dimensional low-pressure tunnel of 6- and 10-percent-thick symmetrical circular-arc airfoil sections at low Mach numbers and several Reynolds numbers. The airfoils were equipped with 0.15-chord plain leading-edge flaps and 0.20-chord plan trailing-edge flaps. The section lift and pitching-moment characteristics were determined for both airfoils with the flaps deflected individually and in combination."
Date: 1953
Creator: Cahill, Jones F.; Underwood, William J.; Nuber, Robert J. & Cheesman, Gail A.
System: The UNT Digital Library
A theoretical study of the effect of forward speed on the free-space sound-pressure field around propellers (open access)

A theoretical study of the effect of forward speed on the free-space sound-pressure field around propellers

From Summary: "The sound-pressure field of a rotating propeller in forward flight in free space is analyzed by replacing the normal-pressure distribution over the propeller associated with thrust and torque by a distribution of acoustic pressure doublets acting at the propeller disk and subject to uniform rectilinear motion. The basic element used to synthesize the field is the pressure field of a concentrated force moving uniformly at subsonic speeds, for which an expression generalizing one of Lamb's for the fixed concentrated force is given. The sound field is expressed by integration over the propeller disk, and also by integration over an effective ring, and is given both for the near pressure field and, in a simpler form, for the far field. Some illustrated examples are calculated and discussed."
Date: October 1953
Creator: Garrick, I. E. & Watkins, Charles E.
System: The UNT Digital Library
The zero-lift drag of a slender body of revolution (NACA RM-10 research model) as determined from tests in several wind tunnels and in flight at supersonic speeds (open access)

The zero-lift drag of a slender body of revolution (NACA RM-10 research model) as determined from tests in several wind tunnels and in flight at supersonic speeds

From Summary: "The results of tests of a slender body of revolution designated the NACA rm-10 have been compiled from various NACA test facilities. Zero-lift drag data are presented for a Reynolds number range from about 1 x 10(6) to 40 x 10(6) from several wind tunnels and from about 12 x 10(6) to 140 x 10(6) from free-flight tests. The Mach numbers covered include 1.5 to 2.4 for the wind-tunnel data and 0.85 to 2.5 for the flight results. The wind tunnel models were tested with and without 60 degree sweptback stabilizing fins and the flight models were tested with stabilizing fins."
Date: April 16, 1953
Creator: Evans, Albert J.
System: The UNT Digital Library
Method for calculating the rolling and yawing moments due to rolling for unswept wings with or without flaps or ailerons by use of nonlinear section lift data (open access)

Method for calculating the rolling and yawing moments due to rolling for unswept wings with or without flaps or ailerons by use of nonlinear section lift data

From Summary: "The methods of NACA reports 865 and 1090 have been applied to the calculation of the rolling-moment and yawing-moment coefficients due to rolling for unswept wings with or without flaps or ailerons. The methods are based on lifting-line theory and allow the use of nonlinear section lift data. The method presented in this report permits calculations to be made somewhat beyond maximum lift for wings having no twist or continuous twist and employing airfoil sections which do not display large discontinuities in the lift curves. Calculations can be made up to maximum lift for wings with discontinuous twist such as that produced by partial-span flaps or ailerons, or both. Two calculated examples are presented in simplified computing forms in order to illustrate the procedures involved."
Date: January 29, 1953
Creator: Martina, Albert P.
System: The UNT Digital Library
Secondary flows and boundary-layer accumulations in turbine nozzles (open access)

Secondary flows and boundary-layer accumulations in turbine nozzles

An investigation of secondary-flow loss patterns originating in three sets of turbine nozzle blade passages was conducted by means of flow-visualization studies and detailed flow measurements. For all cases, high loss values were measured in the fluid downstream of the corners formed by the suction surfaces of the blades and the shrouds, and these losses were accompanied by discharge-angle deviations from design values. Despite the size of the loss regions and angle gradients, over-all mass-average blade efficiencies were of the order of 0.99 and 0.98 and, therefore, are not a good index of blade performance.
Date: April 30, 1953
Creator: Rohlik, Harold E.; Kofskey, Milton G.; Allen, Hubert W. & Herzig, Howard Z.
System: The UNT Digital Library
Transonic Flow Past Cone Cylinders (open access)

Transonic Flow Past Cone Cylinders

"Experimental results are presented for transonic flow post cone-cylinder, axially symmetric bodies. The drag coefficient and surface Mach number are studied as the free-stream Mach number is varied and, wherever possible, the experimental results are compared with theoretical predictions. Interferometric results for several typical flow configurations are shown and an example of shock-free supersonic-to-subsonic compression is experimentally demonstrated" (p. 963).
Date: April 15, 1953
Creator: Solomon, George E.
System: The UNT Digital Library
High-Resolution Autoradiography (open access)

High-Resolution Autoradiography

This investigation was made to adapt wet-process autoradiography to metallurgical samples to obtain high resolution of segregated radioactive elements in microstructures. Results are confined to development of the technique, which was perfected to a resolution of less than 10 microns. The radioactive samples included carbon-14 carburized iron and steel, nickel-63 electroplated samples, a powder product containing nickel-63, and tungsten-185 in N-155 alloy.
Date: June 1, 1953
Creator: Towe, George C.; Gomberg, Henry J. & Freemen, J. W.
System: The UNT Digital Library
A theory for stability and buzz pulsation amplitude in ram jets and an experimental investigation including scale effects (open access)

A theory for stability and buzz pulsation amplitude in ram jets and an experimental investigation including scale effects

From a theory developed on a quasi-one-dimensional-flow basis, it is found that the stability of the ram jet is dependent upon the instantaneous values of mass flow and total pressure recovery of the supersonic diffuser and immediate neighboring subsonic diffuser. Conditions for stable and unstable flow are presented. The theory developed in the report is in agreement with the experimental data of NACA-TN-3506 and NACA-RM-L50K30. A simple theory for predicting the approximate amplitude of small pressure pulsation in terms of mass-flow decrement from minimum-stable mass flow is developed and found to agree with experiments.
Date: July 28, 1953
Creator: Trimpi, Robert L.
System: The UNT Digital Library
Flight Determination of Drag of Normal-Shock Nose Inlets With Various Cowling Profiles at Mach Numbers From 0.9 to 1.5 (open access)

Flight Determination of Drag of Normal-Shock Nose Inlets With Various Cowling Profiles at Mach Numbers From 0.9 to 1.5

External-drag data are presented for normal-shock nose inlets with NACA 1-series, parabolic, and conic cowling profiles. The tests were made at an angle of attack of 0 degrees by using rocket-propelled models in free flight at Mach numbers from 0.9 to 1.5. The Reynolds number based on body maximum diameter varied from 2.5 x 10 sup 6 to 5.5 x 10 sup 6.
Date: September 8, 1953
Creator: Sears, R. I.; Merlet, C. F. & Putland, L. W.
System: The UNT Digital Library
Lift and center of pressure of wing-body-tail combinations at subsonic, transonic, and supersonic speeds (open access)

Lift and center of pressure of wing-body-tail combinations at subsonic, transonic, and supersonic speeds

From Summary: "A method is presented for calculating the lift and centers of pressure of wing-body and wing-body-tail combinations at subsonic, transonic, and supersonic speeds. A set of design charts and a computing table are presented which reduce the computations to routine operations. Comparison between the estimated and experimental characteristics for a number of wing-body and wing-body-tail combinations shows correlation to within + or - 10 percent on lift and to within about + or - 0.02 of the body length on center of pressure."
Date: July 8, 1953
Creator: Pitts, William C.; Nielsen, Jack N. & Kaattari, George E.
System: The UNT Digital Library
Equations, Tables, and Charts for Compressible Flow (open access)

Equations, Tables, and Charts for Compressible Flow

"This report, which is a revision and extension of NACA-TN-1428, presents a compilation of equations, tables, and charts useful in the analysis of high-speed flow of a compressible fluid. The equations provide relations for continuous one-dimensional flow, normal and oblique shock waves, and Prandtl-Meyer expansions for both perfect and imperfect gases. The tables present useful dimensionless ratios for continuous one-dimensional flow and for normal shock waves as functions of Mach number for air considered as a perfect gas" (p. 613).
Date: 1953
Creator: Ames Research Staff
System: The UNT Digital Library
Theoretical combustion performance of several high-energy fuels for ramjet engines (open access)

Theoretical combustion performance of several high-energy fuels for ramjet engines

An analytical evaluation of the air and fuel specific-impulse characteristics of magnesium, magnesium octene-1 slurries, aluminum, aluminum octene-1 slurries, boron, boron octene-1 slurries, carbon, hydrogen, alpha-methylnaphthalene, diborane, pentaborane, and octene-1 is presented. While chemical equilibrium was assumed in the combustion process, the expansion was assumed to occur at fixed composition.
Date: September 14, 1953
Creator: Tower, Leonard K.; Breitwieser, Roland & Gammon, Benson E.
System: The UNT Digital Library
A study of the motion and aerodynamic heating of ballistic missiles entering the earth's atmosphere at high supersonic speeds (open access)

A study of the motion and aerodynamic heating of ballistic missiles entering the earth's atmosphere at high supersonic speeds

From Summary: "A simplified analysis of the velocity and deceleration history of ballistic missiles entering the earth's atmosphere at high supersonic speeds is presented. The results of this motion analysis are employed to indicate means available to the designer for minimizing aerodynamic heating. The heating problem considered involves not only the total heat transferred to a missile by convection, but also the maximum average and local time rates of convective heat transfer."
Date: April 28, 1953
Creator: Allen, H. Julian & Eggers, A. J., Jr.
System: The UNT Digital Library
Supersonic Flow Past Oscillating Airfoils Including Nonlinear Thickness Effects (open access)

Supersonic Flow Past Oscillating Airfoils Including Nonlinear Thickness Effects

"A solution to second order in thickness is derived for harmonically oscillating two-dimensional airfoils in supersonic flow. For slow oscillations of an arbitrary profile, the result is found as a series including the third power of frequency. For arbitrary frequencies, the method of solution for any specific profile is indicated, and the explicit solution derived for a single wedge" (p. 611).
Date: April 20, 1953
Creator: Van Dyke, Milton D.
System: The UNT Digital Library
The Calculation of Pressure on Slender Airplanes in Subsonic and Supersonic Flow (open access)

The Calculation of Pressure on Slender Airplanes in Subsonic and Supersonic Flow

"Under the assumption that a wing, body, or wing-body combination is slender or flying at near sonic velocity, expressions are given which permit the calculation of pressure in the immediate vicinity of the configuration. The disturbance field, in both subsonic and supersonic flight, is shown to consist of two-dimensional disturbance fields extending laterally and a longitudinal field that depends on the streamwise growth of cross-sectional area. A discussion is also given of couplings, between lifting and thickness effects, that necessarily arise as a result of the quadratic dependence of pressure on the induced velocity components" (author).
Date: November 28, 1953
Creator: Heaslet, Max A. & Lomax, Harvard
System: The UNT Digital Library
Impingement of water droplets on wedges and double-wedge airfoils at supersonic speeds (open access)

Impingement of water droplets on wedges and double-wedge airfoils at supersonic speeds

"An analytical solution has been obtained for the equations of motion of water droplets impinging on a wedge in a two-dimensional supersonic flow field with a shock wave attached to the wedge. The closed-form solution yields analytical expressions for the equation of the droplet trajectory, the local rate of impingement and the impingement velocity at any point on the wedge surface, and the total rate of impingement. The analytical expressions are utilized to determine the impingement on the forward surfaces of diamond airfoils in supersonic flow fields with attached shock waves" (p. 85).
Date: April 21, 1953
Creator: Serafini, John S.
System: The UNT Digital Library
Method for studying helicopter longitudinal maneuver stability (open access)

Method for studying helicopter longitudinal maneuver stability

A theoretical analysis of helicopter maneuver stability is made and the results are compared with experimental results for both a single and a tandem rotor helicopter. Techniques are described for measuring in flight the significant stability derivatives for use with the theory to aid in design studies of means for achieving marginal maneuver stability for a prototype helicopter.
Date: October 1953
Creator: Amer, Kenneth B.
System: The UNT Digital Library
A Study of Inviscid Flow About Airfoils at High Supersonic Speeds (open access)

A Study of Inviscid Flow About Airfoils at High Supersonic Speeds

Steady flow about curved airfoils is investigated analytically, first assuming air behaves as an ideal gas, and then assuming it behaves as a thermally perfect, calorically imperfect gas. Conclusions are drawn from the study.
Date: 1953
Creator: Eggers, A. J., Jr.; Syvertson, Clarence A. & Kraus, Samuel
System: The UNT Digital Library
Transverse Vibrations of Hollow Thin-Walled Cylindrical Beams (open access)

Transverse Vibrations of Hollow Thin-Walled Cylindrical Beams

"The variational principle, differential equations, and boundary conditions considered appropriate to the analysis of transverse vibrations of hollow thin-walled cylindrical beams are shown. General solutions for the modes and frequencies of cantilever and free-free cylindrical beams of arbitrary cross section but of uniform thickness are given. The combined influence of the secondary effects of transverse shear deformation, shear lag, and secondary effects of transverse shear deformation, shear lag, and longitudinal inertia is shown in the form of curves for cylinders of rectangular cross section and uniform thickness" (p. 1).
Date: 1953
Creator: Budiansky, Bernard & Kruszewski, Edwin T.
System: The UNT Digital Library