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Her Majesty Queen Elizabeth.

Description: Portrait of Elizabeth Bowes-Lyon, Queen Elizabeth [later known as Queen Elizabeth the Queen Mother], Consort of King George VI of England. She wears six strands of pearls, a tiara, and an embroidered dress with three decorations attached to it. One decoration is the Family Order of King George VI, which features a portrait of the King. The decoration on her left breast is the Garter Star, which features St. George's cross.
Date: [c.1937]
Creator: Wilding, Dorothy, 1893-1976.
Partner: UNT Libraries Government Documents Department

Milk Drop

Description: No Description Available.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: ca. 1936
Creator: Edgerton, Harold Eugene
Partner: UNT College of Visual Arts + Design

Le Gueridon Rouge

Description: A still life painting with a musical instrument, fruit, and a bottle.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: 1939-1952
Creator: Braque, Georges
Partner: UNT College of Visual Arts + Design

The Breda Wind Tunnel

Description: A description of the design and construction of the Breda wind tunnel. The tunnel is equipped with a two-meter throat diameter and a 310 kph velocity potential.
Date: December 1939
Creator: Pittoni, Mario
Partner: UNT Libraries Government Documents Department

Contribution to the Aerodynamics of Rotating-Wing Aircraft

Description: "The chief defect of the investigations up to now was the assumption of a more or less arbitrary "mean" drag coefficient for a section of the blade. This defect is remedied through replacement of the constant coefficient by a function of higher order which corresponds to the polar curve of the employed profile. In that way it is possible to extend the theory to include the entire range from "autogyro" without power input to the driven "helicopter" with forward-tilted rotor axis. The treatment includes the twisted rectangular blade and a non-twisted tapered blade" (p. 1).
Date: December 1939
Creator: Sissingh, G.
Partner: UNT Libraries Government Documents Department

The Effect of Streamlining the Afterbody of an N.A.C.A. Cowling

Description: "The drag and the power cost associated with the changing of the nose of a nacelle from a streamline shape to a conventional N.A.C.A. cowling shape was investigated in the N.A.C.A. 20-foot tunnel. Full-scale propellers and nacelles were used. The increment of drag associated with the change of nose shapes was found to be critically dependent on the afterbody of the nacelle" (p. 1).
Date: December 1939
Creator: Stickle, George W.; Crigler, John L. & Naiman, Irven
Partner: UNT Libraries Government Documents Department

The Effect of Streamlining the Aterbody of an N.A.C.A. Cowling

Description: Report presenting an investigation of the drag and power cost associated with the changing of the nose of a nacelle from a streamline shape to a conventional cowling shape. Full-scale propellers and nacelles were used. The results of the tests showed that the streamline afterbody drag approached that of an airship form and that the added drag due to the open-nose cowling was only a quarter of the drag increase obtained with the other afterbody.
Date: December 1939
Creator: Stickle, George W.; Crigler, John L. & Naiman, Irven
Partner: UNT Libraries Government Documents Department

Liquefied Gas for the Household.

Description: Describes the benefits of using liquefied gas as a means of power in the home, how it is measured and distributed, and its comparative costs.
Date: December 1939
Creator: Senner, Arthur H. (Arthur Henry) & Holbrook, Helen S. (Helen Shepard), b. 1882
Partner: UNT Libraries Government Documents Department

Local instability of columns with I-, Z-, channel, and rectangular-tube sections

Description: From Summary: "Charts are presented for the coefficients in the formulas for the critical compressive stress at which cross-sectional distortion begins in thin-wall columns of I-, Z-, channel, and rectangular-tube sections. The energy method of Timoshenko was used in the theoretical calculations required for the construction of the charts. The deflection equations were carefully selected to give good accuracy. The calculation of the critical compressive stress at stresses above the elastic range is briefly discussed in order to demonstrate the use of the formulas and the charts in engineering calculations. Two illustrative problems are included."
Date: December 1939
Creator: Stowell, Elbridge Z. & Lundquist, Eugene E.
Partner: UNT Libraries Government Documents Department

Modern Methods of Testing

Description: After a brief survey of the commonly used single-value test methods, the importance of the determination of the incipient knock for the octane number is discussed and improvements suggested for the knock testing in the CFR engine. The DVL supercharge test method with its superiority of direct determination of fuel knock in each single cylinder of an airplane engine without involving structural changes, is described and the advantages of a multiple-value method enumerated. A diagrammatic presentation of the knock characteristics is presented.
Date: December 1939
Creator: Seeber, F.
Partner: UNT Libraries Government Documents Department

Observations in flight of the region of stalled flow over the blades of an autogiro rotor

Description: From Summary: "The flow over the inner halves of the rotor blades on a Kellet YG-1B autogiro was investigated in flight by making camera records of the motion of silk streamers attached to the upper surfaces of the blades. These records were analyzed to determine the boundaries of the region within which the flow over the blade sections was stalled for various tip-speed ratios. For the sake of comparison, corresponding theoretical boundaries were obtained. Both the size of the stalled area and its rate of growth with increasing tip-speed ratio were found to be larger than the theory predicted, although experiment agreed with theory with regard to shape and general location of the stalled area."
Date: December 1939
Creator: Bailey, F. J., Jr. & Gustafon, F. B.
Partner: UNT Libraries Government Documents Department

Pressure-Distribution Measurements on a Rectangular Wing With a Partial-Span Split Flap in Curved Flight

Description: "Pressure-distribution tests were made on the 32-foot whirling arm of the Daniel Guggenheim Airship Institute of a rectangular wing of NACA 23012 section to determine the rolling and the yawing moment due to angular velocity in yaw. The model was tested at 0 and 5 degree pitch; 0, +/- 5, and +/- 10 degrees yaw; and with no flap and with split flaps 25, 50 and 75 percent of the wing span and deflected 60 degrees. The results are given in the form of span load distributions and as calculated moment coefficients" (p. 1).
Date: December 1939
Creator: Rokus, Frank G.
Partner: UNT Libraries Government Documents Department

Profile-Drag Investigation of an Airplane Wing Equipped with Rubber Inflatable De-Icer

Description: "The National Advisory Committee for Aeronautics has made profile-drag measurements in flight of a wing which was equipped with a rubber inflatable de-icer and to which various stimulated ice formations were attached. Tuft observations at the stalling speed of the wing with the various drag conditions were made in order to determine the influence on the maximum lift coefficient. The de-icer installation caused an increase of from 10-20% in the profile drag of the plain wing and reduced CL(sub max) about 6%" (p. 1).
Date: December 1939
Creator: Rodert, Lewis A. & Jones, Alun R.
Partner: UNT Libraries Government Documents Department

Protecting Field Borders.

Description: A guide to establishing borders for farm fields, in order to allow for drainage, to prevent woodland encroachment, and to provide wildlife protection.
Date: December 1939
Creator: Davison, Verne E. (Verne Elbert), 1904-
Partner: UNT Libraries Government Documents Department

A Recurrence Formula for Shear-Lag Problems

Description: "The analysis of the bending action in box beams with appreciable shear deformation of the flanges becomes very difficult in the general case of variable cross section and loading. This paper presents a convenient method of solving the problem by the familiar method of dividing the beam into a number of bays that can be assumed to have constant cross section and loading. Application of formerly derived shear-lag formulas leads to a general equation closely analogous in form to the well-known three-moment equation" (p. 1).
Date: December 1939
Creator: Kuhn, Paul
Partner: UNT Libraries Government Documents Department

Stress concentration around an open circular hole in a plate subjected to bending normal to the plane of the plate

Description: "An aluminum-alloy plate containing an open circular hole of diameter large compared with the thickness of the plate was subjected to bending forces normal to the plane of the plate. Deflection and strain measurements were taken for two different loads. Stress concentrations occurred at the edge of the hole and the maximum stresses were tangential to the hole at the ends of the transverse diameter. The maximum stress at the edge of the hole was 1.59 times the computed stress on the net section and 1.85 times the computed stress in a solid plate of the same dimensions subjected to the same bending forces" (p. 1).
Date: December 1939
Creator: Dumont, C.
Partner: UNT Libraries Government Documents Department

Effect of fuel-air ratio, inlet temperature, and exhaust pressure on detonation

Description: From Summary: "An accurate determination of the end-gas condition was attempted by applying a refined method of analysis to experimental results. The results are compared with those obtained in Technical Report no. 655. The experimental technique employed afforded excellent control over the engine variables and unusual cyclic reproducibility. This, in conjunction with the new analysis, made possible the determination of the state of the end-gas at any instant to a fair degree of precision. Results showed that for any given maximum pressure the maximum permissible end-gas temperature increased as the fuel-air ratio was increased. The tendency to detonate was slightly reduced by an increase in residual gas content resulting from an increase in exhaust backpressure with inlet pressure constant."
Date: November 15, 1939
Creator: Taylor, E. S.; Leary, W. A. & Diver, J. R.
Partner: UNT Libraries Government Documents Department

Corrugated Metal Diaphragms for Aircraft Pressure-Measuring Instruments

Description: Note presenting a description of a large number of corrugated diaphragms of beryllium copper, phosphor bronze, and Z-nickel with geometrically similar outlines but various diameters and thicknesses were formed by hydraulic pressing. The apparatus and technique used in the manufacture, testing, and heat treatment are described. Results regarding pressure-deflection curves, load limit, effect of center reinforcing, snap-action diaphragms, deflection traverse, thickness variations, and concentrated central loads are provided.
Date: November 1939
Creator: Wildhack, W. A. & Goerke, V. H.
Partner: UNT Libraries Government Documents Department

The Effect of Compressibility on the Pressure Reading of a Prandtl Pitot Tube at Subsonic Flow Velocity

Description: Errors arising from yawed flow were also determined up to 20 degrees angle of attack. In axial flow, the Prandtl pitot tube begins at w/a approx. = 0.8 to give an incorrect static pressure reading, while it records the tank pressure correctly, as anticipated, up to sonic velocity. Owing to the compressibility of the air, the Prandtl pitot tube manifests compression shocks when the air speed approaches velocity of sound. This affects the pressure reading of the instrument. Because of the increasing importance of high speed in aviation, this compressibility effect is investigated in detail.
Date: November 1939
Creator: Walchner, O.
Partner: UNT Libraries Government Documents Department

The effect of the slipstream on an airplane wing

Description: The conditions which must be met at the slipstream boundary are developed, after which it is shown with the aid of the reflection method how these limiting conditions may be complied with in the case of an airfoil in a propeller slipstream in horizontal flow as well as for the propeller in yaw and with allowance for the slipstream rotation. In connection herewith, it is shown how the effective angles of attack and the circulation distribution with due regard to slipstream effect can be predicted and what inferences may be drawn therefrom for the distribution of lift, drag, and pitching moment.
Date: November 1939
Creator: Franke, A. & Weinig, F.
Partner: UNT Libraries Government Documents Department