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Bending of Rectangular Plates With Large Deflections

Description: 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
Partner: UNT Libraries Government Documents Department

Preliminary Wind-Tunnel Investigation of the Effect of Area Suction on the Laminar Boundary Layer Over an NACA 64A010 Airfoil

Description: Memorandum presenting a preliminary investigation made in the two-dimensional low-turbulence tunnel on an NACA 64A010 airfoil with permeable surfaces to obtain an indication of the stabilizing effect of area suction on the laminar boundary layer. Although the airfoil surface had many waves and irregularities of contour, the data corroborated qualitatively the theoretically predicted stabilizing effect of area suction on a smooth flat plate.
Date: April 26, 1948
Creator: Braslow, Albert L.; Visconti, Fioravante & Burrows, Dale L.
Partner: UNT Libraries Government Documents Department

A General Small-Deflection Theory for Flat Sandwich Plates

Description: Note presenting a small-deflection theory developed for the elastic behavior of orthotropic flat plates in which deflections due to shear are taken into account. The theory covers all types of flat sandwich construction and includes seven physical constants for each plate, of which six are independent.
Date: April 1948
Creator: Libove, Charles & Batdorf, S. B.
Partner: UNT Libraries Government Documents Department

Buckling in Shear of Continuous Flat Plates

Description: "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
Partner: UNT Libraries Government Documents Department

Effects of Surface Finish, of Certain Defects, and of Repair of Defects by Welding on Fatigue Strength of 355-T6 Sand-Castings and Effects of Prior Fatigue Stressing on Tensile Properties

Description: Note presenting tests to evaluate the effects of various surface conditions, certain defects, and repair of some of the defects by welding on the fatigue strength of an aluminum sand-cast alloy. The surfaces studied included as-cast, machined, grit-blasted, and shot-blasted surfaces. Results regarding fatigue and tensile tests are provided.
Date: April 1948
Creator: Howell, F. M.; Stickley, G. W. & Lyst, J. O.
Partner: UNT Libraries Government Documents Department

Compressive Buckling of Simply Supported Plates With Transverse Stiffeners

Description: "Charts are presented for the analysis of the stability under longitudinal compression of simply supported rectangular plates with several equally spaced transverse stiffeners that have both torsional and flexural rigidity" (p. 1).
Date: April 1948
Creator: Budiansky, Bernard & Seide, Paul
Partner: UNT Libraries Government Documents Department

Mining Program: Bureau of Mines Oil-Shale Project, Rifle, Colorado

Description: Report issued by the Bureau of Mines on the development of efficient mining methods for producing oil shale. Characteristics of the oil shale deposits of the Green River are presented. The results of core drilling and sampling in this area are also listed. This report includes tables, illustrations, maps, and photographs.
Date: April 1948
Creator: Gardner, E. D.
Partner: UNT Libraries Government Documents Department

Investigation of Meta-Anthracite in Newport and Providence Counties, Rhode Island: Petrography, Chemical Characteristics, and Geology of Deposits: I. Investigation of the Field and the Physical and Chemical Characteristics of the Deposits; II. Preliminary Geologic Study of the Portsmouth and Cranston Areas, Rhode Island; III. General Conclusions

Description: Report issued by the Bureau of Mines over studies conducted on the meta-anthracite of Rhode Island. The physical and chemical characteristics, geology, and petrography of the deposits are presented in three parts. The methods used in the study are also listed. This report includes tables, maps, photographs, and illustrations.
Date: April 1948
Creator: Toenges, Albert L.; Turnbull, Louis A.; Neale, Arthur; Schopf, J. M.; Abernethy, R. F. & Quinn, Alonzo W.
Partner: UNT Libraries Government Documents Department

Georgia Mica Spots: Cherokee, Upson, Lamar, and Monroe Counties

Description: Report issued by the Bureau of Mines over studies of mica deposits throughout four counties in Georgia. Descriptions of the physical features of the mines, and deposits are presented. This report includes tables, maps, and photographs.
Date: April 1948
Creator: Beck, William A.
Partner: UNT Libraries Government Documents Department

Flood-Prevention Projects at Pennsylvania Anthracite Mines: Progress Report for Fiscal Year Ended June 30, 1947

Description: Report issued by the Bureau of Mines over the progress made on flood prevention in anthracite mines. As stated in the report, "the broad objective of the investigative work was to obtain factual data on: 1. anthracite reserves of Pennsylvania, 2. underground water pools, 3. barrier pillars, 4. the "buried valley" of the Susquehanna River, and 5. infiltration of surface water into underground mine workings" (p. 4). This report includes tables, graphs, maps, photographs, and illustrations.
Date: April 1948
Creator: Ash, S. H.; Cassap, W. E.; Eaton, W. L.; Hughes, Karl; Romischer, W. M. & Westfield, James
Partner: UNT Libraries Government Documents Department

The Influence of the Diameter Ratio on the Characteristics Diagram of the Axial Compressor

Description: With the further development of axial blowers into highly loaded flow machines, the influence of the diameter ratio upon air output and efficiency gains in significance. Clarification of this matter is important for single-stage axial compressors, and is of still greater importance for multistage ones, and particularly for aircraft power plants. Tests with a single-stage axial blower gave a decrease in the attainable maximum pressure coefficient and optimum efficiency as the diameter ratio increased. The decrease must be ascribed chiefly to the guide surface of the hub and housing between the blades increasing with the diameter ratio.
Date: April 1948
Creator: Eckert, B.; Pflüger, F. & Weinig, F.
Partner: UNT Libraries Government Documents Department

Empirical mode constants for calculating frequencies of axial-flow compressor blades

Description: The vibration characteristics of a group of axial-flow compressor blades of similar geometry were investigated. Empirical-mode constants were determined for the first three bending and torsional modes. A comparison of experimentally determined frequencies of a second group of blades with frequencies computed using these mode constants showed that the computed values were correct within 10 percent. The approximate limiting ratios of depth to chord and length to chord below which these constants could not be used to compute the natural frequencies were also found experimentally.
Date: April 23, 1948
Creator: Millenson, M. B. & Wilterdink, P. I.
Partner: UNT Libraries Government Documents Department

Investigation of the aerodynamic and icing characteristics of a recessed fuel cell vent assembly 3: NACA flush-inlet-type vent

Description: An investigation conducted in the icing research tunnel to determine aerodynamic and icing characteristics of two flush-inlet-type fuel cell vent installations. The vent tubes were mounted in two different locations in the two installations. The vents were aerodynamically investigated to obtain vent-tube static-pressure differentials and pressure surveys as a function of tunnel-air velocity and angle of attack.
Date: April 23, 1948
Creator: Ruggeri, Robert S.
Partner: UNT Libraries Government Documents Department

Vibration of turbine blades in a turbojet engine during operation

Description: Report presenting an experimental investigation to determine the vibration phenomena that occur in turbine blades of a typical jet-propulsion engine during service operation; high-temperature strain gages were used to measure the turbine-blade vibrations. Results regarding modes of vibration, centrifugal stresses, and vibration of turbine blades during operation are provided.
Date: April 22, 1948
Creator: Morgan, W. C.; Kemp, R. H. & Manson, S. S.
Partner: UNT Libraries Government Documents Department

Pressure recovery at supersonic speeds through annular duct inlets situated in a region of appreciable boundary layer 1: addition of energy to the boundary layer

Description: Report presenting a model with a nozzle upstream of an annular duct inlet for the purpose of ejecting high-velocity air into the boundary layer of the flow along the forebody tested between Mach numbers of 1.36 and 2.01. Results wind-tunnel data, equivalent pressure recovery, and scale effects are provided.
Date: April 1, 1948
Creator: Davis, Wallace F. & Brajnikoff, George B.
Partner: UNT Libraries Government Documents Department

Appreciation and Prediction of Flying Qualities

Description: "The material given in this report summarizes some of the results of recent research that will aid the designers of an airplane in selecting or modifying a configuration to provide satisfactory stability and control characteristics. The requirements of the NACA for satisfactory flying qualities, which specify the important stability and control characteristics of an airplane from the pilot's standpoint, are used as the main topics of the report. A discussion is given of the reasons for the requirements, of the factors involved in obtaining satisfactory flying qualities, and of the methods used in predicting the stability and control characteristics of an airplane" (p. 1).
Date: April 12, 1948
Creator: Phillips, William H.
Partner: UNT Libraries Government Documents Department

Methods of constructing charts for adjusting test results for the compressive strength of plates for differences in material properties

Description: "Methods are presented for constructing charts suitable for adjusting to standard values plate test results for the critical compressive stress and the average stress at maximum load. The methods take into account the difference between the compressive properties of the material used for the tests and those upon which the design is to be based. Illustrative charts are included for extruded 24S-T and 75S-T aluminum alloys" (p. 1).
Date: April 1948
Creator: Heimerl, George J.
Partner: UNT Libraries Government Documents Department

Friction of solid films on steel at high sliding velocities

Description: Report presenting an investigation to identify the roles of solid-surface films in the mechanisms of sliding and lubrication involved in the mating and compatibility of boundary-lubricated slider surfaces, in the action of extreme-pressure lubricants, and in the operation of slider surfaces not supplied with fluid lubricants. Results regarding the films formed during run-in, films formed by extreme-pressure lubricants, and supplemental or dry-lubrication films are provided.
Date: April 1948
Creator: Johnson, Robert L.; Godfrey, Douglas & Bisson, Edmond E.
Partner: UNT Libraries Government Documents Department

Preliminary Investigation of a Ceramic Lining for a Combustion Chamber for Gas-Turbine Use

Description: Combustion chamber liners for gas turbines and experimental set-ups were tested for failure. A ceramic-lined test chamber was operated at fuel/air ratios up to 0.050. Thermal-shock evaluation indicated that a ceramic lining, which expands after firing, would crack but would not fall apart during operation. Refractoriness of the lining and the resistance to mechanical shock were adequate. In general, shell temperature reductions of approximately 400 deg F were effected by the use of this lining at fuel/air ratios of 0.016 and 0.050. The mechanism of failure of the ceramic lining was induced by sudden heating and cooling during operation.
Date: April 12, 1948
Creator: Woodward, William H. & Bobrowsky, A. R.
Partner: UNT Libraries Government Documents Department

Time requirements for current discharge operations

Description: In order to evaluate the feasibility of segmental discharge equipment, it was necessary to determine the time required for segmental discharge during the current operating procedures. This memorandum details this time study.
Date: April 22, 1948
Creator: Cabell, C. P.
Partner: UNT Libraries Government Documents Department