Intensity, scale, and spectra of turbulence in mixing region of free subsonic jet (open access)

Intensity, scale, and spectra of turbulence in mixing region of free subsonic jet

Report presents the results of the measurements of intensity of turbulence, the longitudinal and lateral correlation coefficients, and the spectra of turbulence in a 3.5-inch-diameter free jet measured with hot-wire anemometers at exit Mach numbers from 0.2 to 0.7 and Reynolds numbers from 192,000 to 725,000.
Date: April 24, 1956
Creator: Laurence, James C.
System: The UNT Digital Library
Analysis and Calculation by Integral Methods of Laminar Compressible Boundary-Layer With Heat Transfer and With and Without Pressure Gradient (open access)

Analysis and Calculation by Integral Methods of Laminar Compressible Boundary-Layer With Heat Transfer and With and Without Pressure Gradient

From Introduction: "The purpose of the present report is to present a comprehensive summary of theoretical investigations of comprehensible laminar boundary layers which have been carried out since 1949 at the Polytechnic Institute of Brooklyn under the sponsorship and with the financial assistance of the National Advisory Committee for Aeronautics. The results of these investigations are contained primarily in references 1 to 7."
Date: April 12, 1955
Creator: Morduchow, Morris
System: The UNT Digital Library
Survey of Portions of the Chromium-Cobalt-Nickel-Molybdenum Quaternary System at 1,200 Degrees C (open access)

Survey of Portions of the Chromium-Cobalt-Nickel-Molybdenum Quaternary System at 1,200 Degrees C

"A survey was made of portions of the chromium-cobalt-nickel-molybdenum quaternary system at 1,200 degrees C by means of microscopic and x-ray diffraction studies. Since the face-centered cubic (alpha) solid solutions form the matrix of almost all practically useful high-temperature alloys, the solid solubility limits of the quaternary alpha phase were determined up to 20 percent molybdenum. The component cobalt-nickel-molybdenum, chromium-cobalt-molybdenum, and chromium-nickel-molybdenum ternary systems were also studied" (p. 1).
Date: April 1952
Creator: Rideout, Sheldon Paul & Beck, Paul A.
System: The UNT Digital Library
Lubrication and cooling studies of cylindrical-roller bearings at high speeds (open access)

Lubrication and cooling studies of cylindrical-roller bearings at high speeds

The results of an experimental investigation of the effect of oil inlet distribution and oil inlet temperature on the inner and outer-race temperatures of 75-millimeter-bore (size 215) cylindrical-roller inner-race-riding cage-type bearings are reported. A radial-load test rig was used over a range of dn values (product of the bearing bore in mm and the shaft speed in r.p.m) from 0.3 x 10(5) to 1.2 x 10(6) and static radial loads from 7 to 1113 pounds.
Date: April 4, 1951
Creator: Macks, E. Fred & Nemeth, Zolton N.
System: The UNT Digital Library
Effect on longitudinal stability and control characteristics of a Boeing B-29 airplane of variations in stick-force and control-rate characteristics obtained through use of a booster in the elevator-control system (open access)

Effect on longitudinal stability and control characteristics of a Boeing B-29 airplane of variations in stick-force and control-rate characteristics obtained through use of a booster in the elevator-control system

A longitudinal stability and control characteristics of a Boeing B-29 airplane have been measured with a booster incorporated in the elevator-control system. Tests were made to determine the effects on the handling qualities of the test airplane of variations in the pilot's control-force gradients as well as the effects of variations in the maximum rate of control motion supplied by the booster. The results of the control-rate investigation indicate that large airplanes may have satisfactory handling qualities with the booster adjusted to give much lower rates of control motion than those normally used by pilots.
Date: April 12, 1950
Creator: Mathews, Charles W.; Talmage, Donald B. & Whitten, James B.
System: The UNT Digital Library
Method of analysis for compressible flow through mixed-flow centrifugal impellers of arbitrary design (open access)

Method of analysis for compressible flow through mixed-flow centrifugal impellers of arbitrary design

A method is presented for analysis of the compressible flow between the hub and the shroud of mixed-flow impellers of arbitrary design. Axial symmetry was assumed, but the forces in the meridional (hub to shroud) plane, which are derived from tangential pressure gradients, were taken into account. The method was applied to an experimental mixed-flow impeller. The analysis of the flow in the meridional plane of the impeller showed that the rotational forces, the blade curvature, and the hub-shroud profile can introduce severe velocity gradients along the hub and the shroud surfaces. Choked flow at the impeller inlet as determined by the analysis was verified by experimental results.
Date: April 13, 1950
Creator: Hamrick, Joseph T.; Ginsburg, Ambrose & Osborn, Walter M.
System: The UNT Digital Library
Calculation of the lateral control of swept and unswept flexible wings of arbitrary stiffness (open access)

Calculation of the lateral control of swept and unswept flexible wings of arbitrary stiffness

A method similar to that of NACA rep. 1000 is presented for calculating the effectiveness and the reversal speed of lateral-control devices on swept and unswept wings of arbitrary stiffness. Provision is made for using either stiffness curves and root-rotation constants or structural influence coefficients in the analysis. Computing forms and an illustrative example are included to facilitate calculations by means of the method. The effectiveness of conventional aileron configurations and the margin against aileron reversal are shown to be relatively low for swept wings at all speeds and for all wing plan forms at supersonic speeds.
Date: April 5, 1951
Creator: Diederich, Franklin W.
System: The UNT Digital Library
An investigation of four wings of square plan form at a Mach number of 6.9 in the Langley 11-inch hypersonic tunnel (open access)

An investigation of four wings of square plan form at a Mach number of 6.9 in the Langley 11-inch hypersonic tunnel

The results of pressure-distribution and force tests of four wings at a Mach number of about 6.9 and a Reynolds number of 0.98 x 10(6) in the Langley 11-inch hypersonic tunnel are presented. The wings had a square plan form, a 5-percent-chord maximum thickness, and diamond, half-diamond, wedge, and half-circular sections.
Date: April 17, 1951
Creator: McLellan, Charles H.; Bertram, Mitchel H. & Moore, John A.
System: The UNT Digital Library
Three-dimensional transonic flow theory applied to slender wings and bodies (open access)

Three-dimensional transonic flow theory applied to slender wings and bodies

The present paper re-examines the derivation of the integral equations for transonic flow around slender wings and bodies of revolution, giving special attention to conditions resulting from the presence of shock waves and to the reduction of the relations to the special forms necessary for the discussion of sonic flow, that is, flow at free-stream Mach number 1.
Date: April 2, 1956
Creator: Heaslet, Max A. & Spreiter, John R.
System: The UNT Digital Library
An evaluation of four experimental methods for measuring mean properties of a supersonic turbulent boundary layer (open access)

An evaluation of four experimental methods for measuring mean properties of a supersonic turbulent boundary layer

From Summary: "Surveys were made through a turbulent boundary layer on a flat plate by means of a pitot probe, an x-ray densitometer, and hot-wire and cold-wire probes. Results from these surveys were analyzed to determine (a) the reliability of the basic data and hence the methods by which they were obtained, and (b) how well the actual distributions of properties in the boundary layer compare with those commonly assumed in semiempirical and theoretical analyses. All surveys were made at the same longitudinal station on the flat plate. The tests were conducted in a an 8- by 8-inch supersonic nozzle. The free-stream Mach number was 3.03 and the Reynolds number was approximately 210,000 based on boundary-layer thickness."
Date: April 19, 1956
Creator: Nothwang, George J.
System: The UNT Digital Library
Blowing-type boundary-layer control as applied to the trailing-edge flaps of a 35 degree swept-wing airplane (open access)

Blowing-type boundary-layer control as applied to the trailing-edge flaps of a 35 degree swept-wing airplane

A wind-tunnel investigation was made to determine the effects on the aerodynamic characteristics of a 35 degree swept-wing airplane of applying blowing-type boundary-layer control to the trailing-edge flaps. Flight tests of a similar airplane were then conducted to determine the effects of boundary-layer control on the handling qualities and operation of the airplane, particularly during landing and take-off. The wind-tunnel and flight tests indicated that blowing over the flaps produced large increases in flap lift increment, and significant increases in maximum lift. The use of blowing permitted reductions in the landing approach speeds of as much as 12 knots.
Date: April 30, 1958
Creator: Kelly, Mark W.; Anderson, Seth B. & Innis, Robert C.
System: The UNT Digital Library
Compressible Laminar Boundary Layer Over a Yawed Infinite Cylinder With Heat Transfer and Arbitrary Prandtl Number (open access)

Compressible Laminar Boundary Layer Over a Yawed Infinite Cylinder With Heat Transfer and Arbitrary Prandtl Number

"The equations are presented for the development of the compressible laminar boundary layer over a yawed infinite cylinder. For compressible flow with a pressure gradient the chordwise and spanwise flows are not independent. Using the Stewartson transformation and a linear viscosity-temperature relation yields a set of three simultaneous ordinary differential equations in a form yielding similar solutions. These equations are solved for stagnation-line flow for surface temperatures from zero to twice the free-stream stagnation temperature and for a wide range of yaw angle and free-stream Mach number" (p. 1017).
Date: April 4, 1957
Creator: Reshotko, Eli & Beckwith, Ivan E.
System: The UNT Digital Library
A Wind-Tunnel Investigation of the Effects of Thrust-Axis Inclination on Propeller First-Order Vibration (open access)

A Wind-Tunnel Investigation of the Effects of Thrust-Axis Inclination on Propeller First-Order Vibration

"Data on the aerodynamic excitation of first-order vibration occurring in a representative three-blade propeller having its thrust axis inclined to the airstream at angles of 0 degree, 4.55 degrees, and 9.80 degrees are included in this report. For several representative conditions the aerodynamic excitation has been computed and compared with the measured values. Blade stresses also were measured to permit the evaluation of the blade stress resulting from a given blade aerodynamic excitation" (p. 1111).
Date: April 20, 1950
Creator: Gray, W. H.; Hallissy, J. M., Jr. & Heath, A. R., Jr.
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
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
Induced Velocities Near a Lifting Rotor With Nonuniform Disk Loading (open access)

Induced Velocities Near a Lifting Rotor With Nonuniform Disk Loading

A method is given for converting known uniformly loaded rotor induced velocities to correspond with arbitrary axisymmetric nonuniform disk load distributions. Numerical results for two specific distributions are given in chart form. Symmetry relations and relations between radial disk loading and wake velocities are developed. Experimental flow measurements are presented and compared with theory. Reasonable agreement is shown in the forward part of the flow when nonuniform loading is assumed, but far behind the rotor the flow is more like that of a wing.
Date: April 1956
Creator: Heyson, Harry H. & Katzoff, S.
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
Survey of hydrogen combustion properties (open access)

Survey of hydrogen combustion properties

This literature digest of hydrogen-air combustion fundamentals presents data on flame temperature, burning velocity, quenching distance, flammability limits, ignition energy, flame stability, detonation, spontaneous ignition, and explosion limits. The data are assessed, recommended values are given, and relations among various combustion properties are discussed. New material presented includes: theoretical treatment of variation in spontaneous ignition lag with temperature, pressure, and composition, based on reaction kinetics of hydrogen-air composition range for 0.01 to 100 atmospheres and initial temperatures of 0 degrees to 1400 degrees k.
Date: April 26, 1957
Creator: Drell, Isadore L. & Belles, Frank E.
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
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
A Study of Second-Order Supersonic Flow Theory (open access)

A Study of Second-Order Supersonic Flow Theory

Second-order solutions of supersonic-flow problems are sought by iteration, using the linearized solution as the first step. For plane and axially symmetric flows, particular solutions of the iteration equation are discovered which reduce the second-order problem to an equivalent linearized problem. Comparison of second-order solutions with exact and numerical results shows great improvement over linearized theory.
Date: April 2, 1952
Creator: Van Dyke, Milton D.
System: The UNT Digital Library