Serial/Series Title
Month
347 Matching Results
Results open in a new window/tab.
Results:
1 - 24 of
347
next
Reciprocity relations in aerodynamics
From Introduction: "The purpose of the present paper is twofold. First, a close connection will be established between reverse-flow theorems in subsonic and supersonic, steady-state wing theory and known reciprocity relations between two solutions of the equation the flow field."
Date:
May 1952
Creator:
Heaslet, Max A. & Spreiter, John R.
System:
The UNT Digital Library
Spin Tests of Two Models of a Low-Wing Monoplane to Investigate Scale Effect in the Model Test Range
Note presenting testing performed on scale models of a modern low-wing monoplane in the 15-foot free-spinning wind tunnel. Results are presented in the form of charts that afford a direct comparison between the spins of the two models for a number of different conditions. The results indicate that, within the range of Reynolds numbers used in the present investigation, such factors as difficulty of ballasting and testing are more important in determining proper model size than the changes in scale effect likely to result from the use of different sizes of models.
Date:
May 1941
Creator:
Donlan, Charles J.
System:
The UNT Digital Library
A General Method of Selecting Foam Inhibitors
Note presenting a criterion for selecting foam inhibitors from insoluble liquids that form emulsions with the foaming liquid. By determining the surface tensions of the foaming liquid and of the additive saturated with that liquid and the interfacial tension between them, spreading and entering coefficients may be calculated. A mechanism of foam inhibition is also described.
Date:
May 1946
Creator:
Robinson, J. V. & Woods, W. W.
System:
The UNT Digital Library
Boundary-Induced Upwash for Yawed and Swept-Back Wings in Closed Circular Wind Tunnels
Report presenting a determination of the tunnel-induced velocities for yawed and swept-back airfoils in a closed circular wind tunnel. Calculations were performed for elemental horseshoe vortices with one tip of the bound vortex on the tunnel axis for a range of yaw angles and bound-vortex lengths.
Date:
May 1947
Creator:
Eisenstadt, Bertram J.
System:
The UNT Digital Library
Experimental and calculated characteristics of several NACA 44-series wings with aspect ratios of 8, 10, and 12 and taper ratios of 2.5 and 3.5
The aerodynamic characteristics of seven unswept tapered wings were determined by calculation from two-dimensional data and by wind-tunnel tests in order to demonstrate the accuracy of the calculations and to show some of the effects of aspect ratio, taper ratio, and root thickness-chord ratio. The characteristics were calculated by the usual application of the lifting-line theory which assumes linear section lift curves and also by an application of the theory which allows the use of nonlinear lift curves. A correction to the lift for the effect of chord was made by using the Jones edge-velocity factor. The wings had aspect ratios of 8, 10, and 12, taper ratios of 2.5 and 3.5, and NACA 44-series airfoils.
Date:
May 1947
Creator:
Neely, Robert H.; Bollech, Thomas V.; Westrick, Gertrude C. & Graham, Robert R.
System:
The UNT Digital Library
Interference of Wing and Fuselage From Tests of 30 Combinations With Triangular and Elliptical Fuselages in the NACA Variable-Density Tunnel
Note presenting tests of 12 wing-fuselage combinations employing triangular and 18 employing elliptical fuselages made in the NACA variable-density tunnel as part of a program to investigate at large values of Reynolds number the aerodynamic effects of wing-fuselage interference. The parameters of combination covered in the investigation were the vertical position of the wing with respect to the fuselage axis, wing shape, and wing-fuselage juncture shape.
Date:
May 1947
Creator:
Sherman, Albert
System:
The UNT Digital Library
A Lifting-Surface-Theory Solution and Tests of an Elliptic Tail Surface of Aspect Ratio 3 with a 0.5-Chord 0.85-Span Elevator
Note presenting an electromagnetic-analogy model of the vortex load, estimated from lifting-line theory with an arbitrary fairing near the elevator tip, on a thin elliptic horizontal tail surface of aspect ratio 3 with a 0.5-chord 0.85-span plain elevator was constructed and tested. A comparison of the aspect-ratio corrections for the partial-span elevators was made with those previously presented for full-span elevators. Wind-tunnel results for a tail surface of the some plan form are presented.
Date:
May 1947
Creator:
Swanson, Robert S.; Crandall, Stewart M. & Miller, Sadie
System:
The UNT Digital Library
Measurements of the Pressure Distribution on the Horizontal Tail Surface of a Typical Propeller-Driven Pursuit Airplane in Flight 2: The Effect of Angle of Sideslip and Propeller Operation
Report presenting measurements in sideslipping flight of the pressure distribution over the horizontal tail surface of a tractor-propeller-driven pursuit airplane to determine the effects of angle of sideslip and propeller operation on the tail-load distribution. Results regarding the reduction of data, effect of sideslip and power on tail loads, effect of sideslip and power on tail moments, and a comparison of the calculated loading with experimental results.
Date:
May 1947
Creator:
Sadoff, Melvin & Clousing, Lawrence A.
System:
The UNT Digital Library
Flight investigation of the effects on airplane static longitudinal stability of a bungee and engine-tilt modifications
Report presenting flight tests to evaluate an elevator stick-force bungee and engine tilt as methods of improving the longitudinal-control characteristics of an existing airplane. The stick-force bungee was found to be the simplest and most effective modification.
Date:
May 1947
Creator:
Rathert, George A., Jr.
System:
The UNT Digital Library
A Dynamic-Model Study of the Effect of Added Weights and Other Structural Variations on the Blade Bending Strains of an Experimental Two-Blade Jet-Driven Helicopter in Hovering and Forward Flight
Report presenting an investigation of the blades of an experimental two-blade jet-driven helicopter when subject to a condition of near resonance between the frequencies of the first elastic bending mode of the blades and third harmonic component of the aerodynamic loading that results in high bending strains in normal flight conditions. Various changes in design configuration on the blade bending strains were explored. Results regarding the preliminary studies, effects of variation in flight conditions and blade configuration, and harmonic analysis are provided.
Date:
May 1955
Creator:
McCarty, John Locke & Brooks, George W.
System:
The UNT Digital Library
General plastic behavior and approximate solutions of rotating disk in strain-hardening range
Report presenting a partly linearized solution of plastic deformation of a rotating disk based on the deformation theory of plasticity and considering finite strains. The method can be used to investigate the general plastic behavior of a rotating disk.
Date:
May 1951
Creator:
Wu, M. H. Lee
System:
The UNT Digital Library
Possible Application of Blade Boundary-Layer Control to Improvement of Design and Off-Design Performance of Axial-Flow Turbomachines
"A theoretical discussion of the application of blade boundary-layer control to increase the efficiency and the stage pressure ratio and to improve off-design performance of turbomachines is presented. A method based on the potential flow of a compressible fluid is developed for designing suction, or ejection, slotted blades having a prescribed velocity distribution along the blade and in the slot. The effect of the boundary layer on the design of the slot and the effect of ejecting gas at stagnation pressures and temperatures different from free-stream values are discussed" (p. 1).
Date:
May 1951
Creator:
Sinnette, John T., Jr. & Costello, George R.
System:
The UNT Digital Library
Charts and tables for use in calculations of downwash of wings of arbitrary plan form
From Summary: "Values of the downwash of a horseshoe vortex in compressible flow are presented in the form of charts and tables. The use of the charts and tables in the calculations of the downwash of wings of arbitrary plan form is discussed. The results of a few calculations are compared with experimental results."
Date:
May 1951
Creator:
Diederich, Franklin W.
System:
The UNT Digital Library
Floating characteristics of a plain and a horn-balanced rudder at spinning attitudes as determined from rotary tests on a model of a typical low-wing personal-owner airplane
Report presenting an investigation to determine the floating characteristics of full-length plain and horn-balanced rudders during rotary tests at spinning attitudes on a scale model of a typical low-wing personal-owner airplane. The investigation included the determination of the effects of the horizontal tail and the wing on the rudder floating characteristics.
Date:
May 1951
Creator:
Bihrle, William, Jr.
System:
The UNT Digital Library
Turbulence-Intensity Measurements in a Jet of Air Issuing From a Long Tube
Report presenting data for turbulent-velocity-fluctuation components and mean-velocity distributions measured in the subsonic jet issuing from a pipe in which a fully developed turbulent flow was established. Axial and radial components of the fluctuation velocities were examined as functions of Reynolds number and position in the jet.
Date:
May 1951
Creator:
Little, Barney H., Jr. & Wilbur, Stafford W.
System:
The UNT Digital Library
Torsional Strength of Stiffened D-Tubes
"The present report covers a series of torsional tests on stiffened D-tubes of alclad 24S-T3 aluminum alloy having a cross section similar to the NACA 0012 airfoil section and a closing web at 30 percent of the chord. The stiffeners consisted of ribs and stringers. An average-strength chart has been developed for this type of structure that takes into account the skin thickness, rib spacing, and stringer spacing. This chart may also be used for unstiffened D-tubes" (p. 1).
Date:
May 1951
Creator:
Kavanaugh, E. S. & Drinkwater, W. D.
System:
The UNT Digital Library
On the Application of Mathieu Functions in the Theory of Subsonic Compressible Flow Past Oscillating Airfoils
Note presenting an account of explicit solutions in terms of Mathieu functions of the problem of two-dimensional subsonic compressible flow past oscillating airfoils. The results are applied to the calculation of three-dimensional corrections for the two-dimensional theory and the effect of the incorporation of the three-dimensional effects on the Mathieu function solution of the two-dimensional problem is shown.
Date:
May 1951
Creator:
Reissner, Eric
System:
The UNT Digital Library
On Two-Dimensional Flow After a Curved Stationary Shock (With Special Reference to the Problem of Detached Shock Waves)
Note presenting an analysis of the problem of two-dimensional flow behind a curved stationary shock wave. The method assumes a given shock-wave shape, which automatically determines certain initial conditions on flow variables, and flow-pattern, including any body shape, follows from initial conditions.
Date:
May 1951
Creator:
Shu, S. S.
System:
The UNT Digital Library
Some effects of tail height and wing plan form on the static longitudinal stability characteristics of a small-scale model at high subsonic speeds
Report presenting an investigation in the high-speed 7- by 10-foot tunnel to determine some effects of tail height and wing plan form on the static longitudinal stability characteristics of a complete, small-scale model at high subsonic speeds. It had both a low-tail and high-tail position. Results regarding the lift and drag characteristics and longitudinal stability characteristics are provided.
Date:
May 1957
Creator:
Few, Albert G., Jr. & King, Thomas J., Jr.
System:
The UNT Digital Library
Cascade investigation of a related series of 6-percent-thick guide-vane profiles and design charts
Report presenting a description of a new blade series designed to operate at near choking inlet Mach numbers and to have near maximum critical Mach numbers by employing high aerodynamic loading of the profiles in the leading-edge region. Results regarding aerodynamic characteristics and prediction of high-speed performance are provided.
Date:
May 1957
Creator:
Dunavant, James C.
System:
The UNT Digital Library
Heat-Loss Characteristics of Hot-Wire Anemometers at Various Densities in Transonic and Supersonic Flow
Note presenting an experimental investigation of the heat-loss characteristics of heated fine wires suitable for use as anemometers in turbulence research. The effects of each of the several variables on the heat-loss characteristics of both normally oriented and swept wires were measured. The temperature-loading effects were found to cause large sensitivity differences between constant-temperature and constant-current operation.
Date:
May 1955
Creator:
Spangenberg, W. G.
System:
The UNT Digital Library
Charts for the analysis of flow in a whirling duct
From Summary: "Charts are developed for the analysis of flow in a whirling constant-diameter duct. These charts permit the determination of the duct-exit Mach number, or the Mach number at any point along the duct, for practical ranges of duct-inlet Mach number, duct-tip Mach number, friction factor, ratio of ambient temperature to duct-flow total temperature, ratio of duct-tip radius to duct hydraulic diameter, and heat conductivity through the duct wall and surrounding material. The method of using the charts is illustrated through the computation of a sample problem."
Date:
May 1957
Creator:
Makofski, Robert A.
System:
The UNT Digital Library
Lift and moment responses to penetration of sharp-edged traveling gusts, with application to penetration of weak blast waves
Report presenting calculations of the lift and moment responses to penetration of sharp-edged traveling gusts for wings in incompressible and supersonic two-dimensional flow, for wide delta and rectangular wings in supersonic flow, and for very narrow delta wings. The results of the calculations indicate that the forward speed of the gusts has a large effect on the lift- and moment-response functions.
Date:
May 1957
Creator:
Drischler, Joseph A. & Diederich, Franklin W.
System:
The UNT Digital Library
On flow of electrically conducting fluids over a flat plate in the presence of a transverse magnetic field
Report presenting a study of the use of a magnetic field to control the motion of electrically conducting fluids. Results indicated that the skin friction and heat-transfer rate are reduced when the transverse magnetic field is fixed relative to the plate and increased when fixed relative to the fluid.
Date:
May 1957
Creator:
Rossow, Vernon J.
System:
The UNT Digital Library