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Bending of Rectangular Plates With Large Deflections

Description: "The solution of Von Karman's fundamental equations for large deflections of plates is presented for the case of a simply supported rectangular plate under combined edge compression and lateral loading. Numerical solutions are given for square plates and for rectangular plates with a width-span ratio of 3:1. The effective widths under edge compression are compared with effective widths according to Von Karman, Bengston, Marguerre, and Cox and with experimental results by Ramberg, Mcpherson, and Levy" (p. 1).
Date: May 27, 1941
Creator: Levy, Samuel
Partner: UNT Libraries Government Documents Department

Blockage Corrections for Three-Dimensional-Flow Closed-Throat Wind Tunnels, With Consideration of the Effect of Compressibility

Description: "Theoretical blockage corrections are presented for a body of revolution and for a three-dimensional unswept wing in a circular or rectangular wind tunnel. The theory takes account of the effects of the wake and of the compressibility of the fluid, and is based on the assumption that the dimensions of the model are small in comparison with those of the tunnel throat. Formulas are given for correcting a number of the quantities, such as dynamic pressure and Mach number, measured in wing-tunnel tests. The report presents a summary and unification of the existing literature on the subject" (p. 771).
Date: 1950
Creator: Herriot, John G.
Partner: UNT Libraries Government Documents Department

The Variation in Engine Power With Altitude Determined From Measurements in Flight With a Hub Dynamometer

Description: "The rate of change in power of aircraft engines with altitude has been the subject of considerable discussion. Only a small amount of data from direct measurements of the power delivered by airplane engines during flight, however, has been published. This report presents the results of direct measurements of the power delivered by a Liberty 12 airplane engine taken with a hub dynamometer at standard altitudes from zero to 13,000 feet. Six flights were made with the engine installed in a modified DH-4 airplane" (p. 323).
Date: May 7, 1928
Creator: Gove, W. D.
Partner: UNT Libraries Government Documents Department

On Panel Flutter and Divergence of Infinitely Long Unstiffened and Ring-Stiffened Thin-Walled Circular Cylinders

Description: "A preliminary theoretical investigation of the panel flutter and divergence of infinitely long, unstiffened and ring-stiffened thin-walled circular cylinders is described. Linearized unsteady potential-flow theory is utilized in conjunction with Donnell's cylinder theory to obtain equilibrium equations for panel flutter. Where necessary, a simplified version of Flugge's cylinder theory is used to obtain greater accuracy. By applying Nyquist diagram techniques, analytical criteria for the location of stability boundaries are derived. A limited number of computed results are presented" (p. 475).
Date: January 11, 1956
Creator: Leonard, Robert W. & Hedgepeth, John M.
Partner: UNT Libraries Government Documents Department

On Traveling Waves in Beams

Description: "The basic equations of Timoshenko for the motion of vibrating nonuniform beams, which allow for effects of transverse shear deformation and rotary inertia, are presented in several forms, including one in which the equations are written in the directions of the characteristics. The propagation of discontinuities in moment and shear, as governed by these equations, is discussed. Numerical traveling-wave solutions are obtained for some elementary problems of finite uniform beams for which the propagation velocities of bending and shear discontinuities are taken to be equal" (p. 359).
Date: October 28, 1952
Creator: Leonard, Robert W. & Budiansky, Bernard
Partner: UNT Libraries Government Documents Department

Aircraft Accidents: Methods of Analysis

Description: This report is a revision of NACA-TR-357. It was prepared by the Committee on Aircraft Accidents. The purpose of this report is to provide a basis for the classification and comparison of aircraft accidents, both civil and military.
Date: June 22, 1936
Creator: Committee on Aircraft Accidents
Partner: UNT Libraries Government Documents Department

Aircraft Accidents: Method of Analysis

Description: The revised report includes the chart for the analysis of aircraft accidents, combining consideration of the immediate causes, underlying causes, and results of accidents, as prepared by the special committee, with a number of the definitions clarified. A brief statement of the organization and work of the special committee and of the Committee on Aircraft Accidents; and statistical tables giving a comparison of the types of accidents and causes of accidents in the military services on the one hand and in civil aviation on the other, together with explanations of some of the important differences noted in these tables.
Date: January 28, 1930
Creator: Committee on Aircraft Accidents
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of Airfoils 5: Continuation of Reports Nos. 93, 124, 182, and 244

Description: "This collection of data on airfoils has been made from published reports of a number of the leading aerodynamic laboratories of this country and Europe. The information which was originally expressed according to the different customs of the several laboratories is here presented in a uniform series of charts and tables suitable for the use of designing engineers and for purposes of general reference. The authority for the results here presented is given as the name of the laboratory at which the experiments were conducted, with the size of the model, wind velocity, and year of tests" (p. 139).
Date: April 1928
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of Aerofoils

Description: The object of this report is to bring together the investigations of the various aerodynamic laboratories in this country and Europe upon the subject of aerofoils suitable for use as lifting or control surfaces on aircraft. The data have been so arranged as to be of most use to designing engineers and for the purposes of general reference. The absolute system of coefficients has been used, since it is thought by the National Advisory Committee for Aeronautics that this system is the one most suited for international use, and yet is one for which a desired transformation can be easily made. For this purpose a set of transformation constants is included in this report.
Date: 1921~
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of Airfoils 3: Continuation of Reports Nos. 93 and 124

Description: "This collection of data on airfoils has been made from the published reports of a number of the leading aerodynamic laboratories of this country and Europe. The information which was originally expressed according to the different customs of the several laboratories is here presented in a uniform series of charts and tables suitable for the use of designing engineers and for purposes of general reference. The absolute system of coefficients has been used, since it is thought by the National Advisory Committee for Aeronautics that this is the one most suited for international use and yet is one for which a desired transformation can be easily made" (p. 397).
Date: 1924~
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of Airfoils 4: Continuation of Reports Nos. 93, 124, and 182

Description: This collection of data on airfoils has been made from the published reports of a number of the leading Aerodynamic Laboratories of this country and Europe. The information which was originally expressed according to the different customs of the several laboratories is here presented in a uniform series of charts and tables suitable for the use of designing engineers and for purposes of general reference. The authority for the results here presented is given as the name of the laboratory at which the experiments were conducted, with the size of the model, wind velocity, and year of test.
Date: September 1926
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of Airfoils 6: Continuation of Reports Nos. 93, 124, 182, 244, and 286

Description: "This collection of data on airfoils has been made from the published reports of a number of the leading aerodynamic laboratories of this country and Europe. The information which was originally expressed according to the different customs of the several laboratories is here presented in a uniform series of charts and tables suitable for use of designing engineers and for purposes of general reference. The authority for the results here presented is given as the name of the laboratory at which the experiments were conducted, with the size of the model, wind velocity, and year of test" (p. 213).
Date: 1930~
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of Aerofoils 2: Continuation of Report No. 93

Description: "This collection of data on aerofoils has been made from the published reports of a number of the leading aerodynamic laboratories of this country and Europe. The information which was originally expressed according to the different customs of the several laboratories is here presented in a uniform series of charts and tables suitable for the use of designing engineers and for purposes of general reference. The absolute system of coefficients has been used, since it is thought by the National Advisory Committee for Aeronautics that this system is the one most suited for international use, and yet is one for which a desired transformation can be easily made" (p. 423).
Date: 1923~
Partner: UNT Libraries Government Documents Department

Blower Cooling of Finned Cylinders

Description: "Several electrically heated finned steel cylinders enclosed in jackets were cooled by air from a blower. The effect of the air conditions and fin dimensions on the average surface heat-transfer coefficient q and the power required to force the air around the cylinders were determined. Tests were conducted at air velocities between the fins from 10 to 130 miles per hour and at specific weights of the air varying from 0.046 to 0.074 pound per cubic foot. The fin dimensions of the cylinders covered a range in pitches from 0.057 to 0.25 inch average fin thicknesses from 0.035 to 0.04 inch, and fin widths from 0.67 to 1.22 inches" (p. 269).
Date: November 14, 1936
Creator: Schey, Oscar W. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department

Nomenclature for Aeronautics

Description: A report presenting the nomenclature and last of symbols to be used in technical reports created by NACA. The purpose of the Committee in the preparation and publication of this report is to secure uniformity in the official documents of the government and, as far as possible, in technical and other commercial publications. This report supersedes all previous publications of the Committee on this subject.
Date: 1921
Creator: United States. National Advisory Committee for Aeronautics.
Partner: UNT Libraries Government Documents Department

Design of Wind Tunnels and Wind Tunnel Propellers 2

Description: This report is a continuation of National Advisory Committee for Aeronautics report no. 73. The variations in velocity and direction of the wind stream were studied by means of a recording air speed meter and a recording yawmeter. The work was carried on both in a 1-foot diameter model tunnel and in a 5-foot full-size tunnel, and wherever possible comparison was made between them. It was found that placing radial vanes directly before the propeller in the exit cone increased the efficiency of the tunnel to a considerable extent and also gave a steadier flow.
Date: 1921
Creator: Norton, F. H. & Warner, Edward P.
Partner: UNT Libraries Government Documents Department

Statical Longitudinal Stability of Airplanes

Description: This report, which is a continuation of the "Preliminary report on free flight testing" (report no. NACA-TR-70), presents a detailed theoretical analysis of statical stability with free and locked controls and also the results of many free flight test on several types of airplanes. In developing the theory of stability with locked controls an expression for pitching moment is derived in simple terms by considering the total moment as the sum of the moments due to wings and tail surface. This expression, when differentiated with respect to angle of incidence, enables an analysis to be made of the factors contributing to the pitching moment.
Date: 1921
Creator: Warner, Edward P.
Partner: UNT Libraries Government Documents Department

Wind Tunnel Studies in Aerodynamic Phenomena at High Speed

Description: A great amount of research and experimental work has been done and fair success obtained in an effort to place airplane and propeller design upon an empirical basis. However, one can not fail to be impressed by the apparent lack of data available toward establishing flow phenomena upon a rational basis, such that they may be interpreted in terms of the laws of physics. With this end in view it was the object of the authors to design a wind tunnel differing from the usual type especially in regard to large power and speed of flow.
Date: 1921
Creator: Caldwell, F. W. & Fales, E. N.
Partner: UNT Libraries Government Documents Department

Some New Aerodynamical Relations

Description: This report contains three new relations extending the modern theory of aeronautics. The first part contains a relation between the power absorbed by an aerofoil and the power absorbed by a propeller. In the second part the exactness of the ordinary formula for the induced drag of an aerofoil is examined and the error is determined. In the third part the author shows that for the calculation of the air forces on bodies of considerable volume the imaginary sources and sinks equivalent to the flow around the body can be used in the same way as vortices are used for the calculation of lift and induced drag of wings.
Date: 1923
Creator: Munk, Max M.
Partner: UNT Libraries Government Documents Department

Some Problems on the Lift and Rolling Moment of Airplane Wings

Description: This report deals with the application of the airfoil and twisted wing theory to the calculation of the lift and rolling moment of airplane wings. Most of the results arrived at are strictly true only for wings of elliptic plan form. The investigation aims to give some indications of the accuracy with which the results can be applied to the wing forms in actual use.
Date: 1925
Creator: Scarborough, James B.
Partner: UNT Libraries Government Documents Department

A Simplified Method for Approximating the Transient Motion in Angles of Attack and Sideslip During a Constant Rolling Maneuver

Description: "The transient motion in angles of attack and sideslip during a constant rolling maneuver has been analyzed. Simplified expressions are presented for the determination of the pertinent modes of motion as well as the modal coefficient corresponding to each mode. Calculations made with and without the derivatives for side force due to sideslip and lift-curve slope indicate that although these derivatives increase the total damping of the system they do not markedly affect the transient motion" (p. 131).
Date: May 22, 1956
Creator: Sternfield, Leonard
Partner: UNT Libraries Government Documents Department

The Small Angular Oscillations of Airplanes in Steady Flight

Description: "This investigation was carried out by the National Advisory Committee for Aeronautics at the request of the Army Air Service to provide data concerning the small angular oscillations of several types of airplanes in steady flight under various atmospheric conditions. The data are of use in the design of bomb sights and other aircraft instruments. The method used consisted in flying the airplane steadily in one direction for at least one minute, while recording the angle of the airplane with the sun by means of a kymograph" (p. 283).
Date: 1924
Creator: Norton, F. H.
Partner: UNT Libraries Government Documents Department

Small Bending and Stretching of Sandwich-Type Shells

Description: "A theory has been developed for small bending and stretching of sandwich-type shells. This theory is an extension of the known theory of homogeneous thin elastic shells. It was found that two effects are important in the present problem, which are not normally of importance in the theory of curved shells: (1) the effect of transverse shear deformation and (2) the effect of transverse normal stress deformation" (p. 1).
Date: 1950
Creator: Reissner, Eric
Partner: UNT Libraries Government Documents Department

A Study of Airplane Maneuvers With Special Reference to Angular Velocities

Description: "This investigation was undertaken by the National Advisory Committee for Aeronautics for the purpose of increasing our knowledge on the behavior of the airplane during various maneuvers and to obtain values of the maximum angular velocities and accelerations in flight. The method consisted in flying a JN4H airplane through various maneuvers while records were being taken of the control position, the air speed, the angular velocity and the acceleration along the Z axis. The results showed that the maximum angular velocity about the X axis of radians per second in a barrel roll" (p. 563).
Date: 1923
Creator: Reid, H. J. E.
Partner: UNT Libraries Government Documents Department