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Approximate Calculation of Turbulent Boundary-Layer Development in Compressible Flow
Note presenting numerical solutions of quantities appearing in the Karman momentum equation for the development of a turbulent boundary layer in plane and in radial compressible flows along thermally insulted surfaces in tabular form for a rnage of Mach numbers from 0.100 to 10. Through use of the tables, approximate calculation of boundary-layer growth is reduced to routine arithmetic computation.
Date:
April 1951
Creator:
Tucker, Maurice
System:
The UNT Digital Library
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.
Date:
April 1958
Creator:
Valentine, E. Floyd
System:
The UNT Digital Library
Approximate Theory for Calculation of Lift of Bodies, Afterbodies, and Combinations of Bodies
Note presenting an expression developed for the lift of a slender afterbody in terms of the "slender-body" approximate potential at the after end in conjunction with a suitably calculated value of the potential at the forward end. The same expression is used to compute the part of the interference lift generated by the presence of a neighboring body, due to the interference upwash. The lift is determined for a cone-cylinder body, a cylindrical afterbody of a slender wing-body combination, and three combinations of bodies to illustrate the method.
Date:
April 1952
Creator:
Moskowitz, Barry
System:
The UNT Digital Library
Axial-flow fan and compressor blade design data on 52.5 degrees stagger and further verification of cascade data by rotor tests
From Summary: "Previous tests of blower-blade sections have been extended by a series of tests at 52.5 degrees stagger. The results of these tests have been combined with the earlier test results and are presented in new blade design charts which supersede those previously presented. An investigation in a test blower over a range of stagger from 44 degrees to 65 degrees has shown that for blades at a solidity of 1.0, the two-dimensional cascade data predict the turning angle to within 1/2 degrees."
Date:
April 1947
Creator:
Bogdonoff, Seymour M. & Hess, Eugene E.
System:
The UNT Digital Library
The Background of Detonation
Note presenting a determination of the relative merits of various fuels for use in high compress engines. The main purpose is to discuss a phase that has not been given much attention in previous studies; specifically, the standpoint of the influence of charge temperatures and pressures on the temperatures and pressures after combustion.
Date:
April 1922
Creator:
Sparrow, Stanwood W.
System:
The UNT Digital Library
Bending of Rectangular Plates With Large Deflections
Note presenting Von Kármán's equations for thin plates with large deflections are solved for the special cases of rectangular plates with ratios of length to width of 1.5 and 2 and loaded by uniform normal pressure. The boundary conditions are such to approximate panels with riveted edges under normal pressure greater than that of the surrounding panels.
Date:
April 1948
Creator:
Wang, Chi-Teh
System:
The UNT Digital Library
Buckling in Shear of Continuous Flat Plates
"As basic information for the design of thin-web spars, the theoretical shear buckling stress is presented for an infinitely long, clamped plate divided into square panels by rigid intermediate supports. In addition, results are given for the shear buckling stress of a plate of infinite length and width having intermediate rigid supports that form an array of square panels. The results indicate the fallacy of the usually made assumption that each panel buckles in shear as if it were simply supported along the intermediate supports" (p. 1).
Date:
April 1948
Creator:
Budiansky, Bernard; Connor, Robert W. & Stein, Manuel
System:
The UNT Digital Library
Bursting Strength of Unstiffened Pressure Cylinders with Slits
Note presenting internal-pressure tests made on aluminum-alloy unstiffened cylinders with precut slits to study the effect of slit length and curvature on the hoop stress developed at the bursting pressure. The results are predicted with good accuracy by applying a curvature correction to the method presented in a previous report for computing the strength of flat plates with cracks.
Date:
April 1957
Creator:
Peters, Roger W. & Kuhn, Paul
System:
The UNT Digital Library
A calculation study of wing-aileron flutter in two degrees of freedom for two-dimensional supersonic flow
Report presenting the results of some sample calculations for the bending-aileron and torsion-aileron flutter of an idealized wing-aileron system for several values of Mach number in supersonic flow and some subsonic Mach numbers. The results are preliminary but may provide some knowledge of the influence of variations in certain parameters and to indicate some of the differences in the trends at high and low speeds.
Date:
April 1954
Creator:
Woolston, Donald S. & Huckel, Vera
System:
The UNT Digital Library
Calculations of the rate of thermal dissociation of air behind normal shock waves at Mach numbers of 10, 12, and 14
Report presenting the rate equation for the dissociation of air, based on simple-collision theory, and the numerical values of the factors that enter it. The rate equation and conservation equations for a flowing dissociating gas are solved for the conditions behind normal shock waves at Mach numbers of 10, 12, and 14. Results regarding the adjustment of translation, rotation, and vibration and adjustment of dissociation are provided.
Date:
April 1956
Creator:
Wood, George P.
System:
The UNT Digital Library
Center of pressure coefficients for airfoils at high speeds
"It has been customary to calculate the strength of the rear wing beam for the 'high speed' condition on the assumption that the center of pressure was at 0.50 of the wing chord. It can be shown that this assumption is not justified, regardless of the utility of a 'high speed' condition in strength calculations" (p. 1).
Date:
April 1922
Creator:
Diehl, W. S.
System:
The UNT Digital Library
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.
Date:
April 1958
Creator:
Staff of the Lewis Laboratory
System:
The UNT Digital Library
Characteristics of Two Sharp-Nosed Airfoils Having Reduced Spinning Tendencies
"According to Mr. L.D. Bell, of the Consolidated Aircraft Corporation, certain undesirable spinning characteristics of a commercial airplane were eliminated by the addition of a filler to the forward part of the wing to give it a sharp leading edge. To ascertain what aerodynamic effects result from such a change of section, two airfoils having sharp leading edges were tested in the variable-density wind tunnel. Both sections were derived by modifying the Gott. 398. The tests, which were made at a large value of the Reynolds Number, were carried to very large angles of attack to provide data for application to flight at angles of attack well beyond the stall" (p. 1).
Date:
April 1932
Creator:
Jacobs, Eastman N.
System:
The UNT Digital Library
Charts expressing the time, velocity, and altitude relations for an airplane diving in a standard atmosphere
In this report charts are given showing the relation between time, velocities, and altitude for airplanes having various terminal velocities diving in a standard atmosphere. The range of starting altitudes is from 8,000 to 32,000 feet, and the terminal velocities vary from 150 to 550 miles per hour. A comparison is made between an experimental case and the results obtained from the charts. Examples pointing out the use of the charts are included.
Date:
April 1937
Creator:
Pearson, H. A.
System:
The UNT Digital Library
Charts for the Rapid Calculation of the Work Required to Compress Dry Air
Report presenting a study of accurate values of the specific heat for dry air applied to the calculation of work required to compress dry air. Two charts are provided that allow the work of compression to be determined from the initial temperature, overall pressure ratio, and either the compression exponent or adiabatic efficiency of the compressor.
Date:
April 1946
Creator:
Benser, William A.; Wilcox, Ward W. & Voit, Charles H.
System:
The UNT Digital Library
Charts of thermodynamic properties of air and combustion products from 300 degrees to 3500 degrees R
Report presenting charts that permit the determination of enthalpy change for various processes regarding the thermodynamic data of gas properties. Some examples using the charts to solve problems are provided.
Date:
April 1950
Creator:
English, Robert E. & Wachtl, William W.
System:
The UNT Digital Library
Circumferential Distribution of Propeller-Slipstream Total-Pressure Rise at One Radial Station of a Twin-Engine Transport Airplane
Note presenting flight tests on a twin-engine transport airplane to determine the effects of fuselage-nacelle interference on the circumferential distribution of the rise in total pressure at one radial station behind the propellers. The effects of the flow interference on the operation of a simple propeller-thrust indicator are investigated. Results regarding the effect of airspeed at full power, effect of wing flaps in approach condition, effect of power in cruise condition, effect of angle of yaw in the cruise condition, effect of engine cowl flaps in the approach condition, and thrustmeter-tube locations are provided.
Date:
April 1955
Creator:
Vogeley, A. W. & Hart, H. A.
System:
The UNT Digital Library
Coefficient of friction and damage to contact area during the early stages of fretting 2: steel, iron, iron oxide, and glass combinations
Report presenting experiments to study the start of fretting and cause of damage during the early stages of fretting of steel-steel combinations at a frequency 5 cycles per minute, an amplitude of 0.006 inch, a load of 150 grams, in air with relative humidity of less than 10 percent. Pure iron, glass, and iron oxide powder compacts were used in supplementary experiments.
Date:
April 1954
Creator:
Bailey, John M. & Godfrey, Douglas
System:
The UNT Digital Library
Collection and Analysis of Hinge-Moment Data on Control-Surface Tabs
Report presenting an analysis of wind-tunnel data on the hinge-moment characteristics of control-surface tabs. Results regarding the correlation of section data, correlation of finite-span data, and effect of Mach number are provided.
Date:
April 1947
Creator:
Purser, Paul E. & Cook, Charles B.
System:
The UNT Digital Library
A collection of data for zero-lift damping in roll of wing-body combinations as determined with rocket-powered models equipped with roll-torque nozzles
Report presenting the zero-lift damping-in-roll derivative as experimentally determined through high subsonic, transonic, and low supersonic speeds by a torque-nozzle forced-roll technique utilizing rocket-propelled models. Data from the the investigations is used to show the effects of wing plan form and airfoil section and the effects of aeroelasticity. Results regarding sweepback, aspect ratio, taper ratio, thickness ratio, airfoil-section shape, delta wings, increase in number of semispan wings from three to four, aeroelastic effects, and comparisons with theory are provided.
Date:
April 1957
Creator:
Stone, David G.
System:
The UNT Digital Library
Collection of Test Data for Lateral Control With Full-Span Flaps
Report presenting a collection of available test data on lateral control with full-span flaps. Internal-control effectiveness and hinge-moment data were obtained from two-dimensional, three-dimensional, and flight tests. Results regarding slot-lip and flap-trailing-edge ailerons, spoiler-type ailerons other than slot-lip ailerons, ailerons with retractable-type flaps, and application of data to specific airplane design are provided.
Date:
April 1948
Creator:
Fischel, Jack & Ivey, Margaret F.
System:
The UNT Digital Library
Combined Natural- and Forced-Convection Laminar Flow and Heat Transfer of Fluids With and Without Heat Sources in Channels With Linearly Varying Wall Temperatures
Note presenting an analysis of the flow of fluids with and without heat sources and subject to body forces between two plane parallel surfaces which are oriented in the direction of the generating body force under the condition that the temperature vary linearly along these surfaces. Results regarding the velocity and temperature distributions, heat transfer, and fluid flow are provided.
Date:
April 1954
Creator:
Ostrach, Simon
System:
The UNT Digital Library
Comparing the Performance of Geometrically Similar Airplanes
"This note has been prepared for the National Advisory Committee for Aeronautics. It deals with the model rules relating to aeronautical problems, and shows how the characteristics of one airplane can be determined from those of another airplane of different weight or size, and of similar type. If certain rules for the ratios of the dimensions, the weights and the horsepower are followed, a small low-powered airplane can be used for obtaining information as to performance, stability, controllability and maneuverability of a larger prototype, and contrariwise" (p. 1).
Date:
April 1924
Creator:
Munk, Max M. & Warner, Edward P.
System:
The UNT Digital Library
Comparison between predicted and observed performance of gas-turbine stator blade designed for free-vortex flow
Report presenting a comparison between the calculated design performance of a gas-turbine stator blade and its performance in a sector of an annular cascade tunnel. The gas velocities on the blade surface were computed by the stress filament method and compared with experimental values, with which they agreed satisfactorily. Results regarding discharge angle, vane-surface-velocity distribution, tangential- and axial-velocity distribution, and radial-equilibrium consideration are provided.
Date:
April 1949
Creator:
Huppert, M. C. & MacGregor, Charles
System:
The UNT Digital Library