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100 Areas Technical Activities Report - Physics, January 1947

Description: Four routine shutdowns were experienced during the month. A measurable amount of the excess reactivity held in the control rods at the first of the month has been lost in the decrease in the average accumulated exposure of all the metal in the pile. The vertical safety rod guides have been measured for vertical alignment by the Maintenance Dept. A definite pattern has been found in the misalignment of the guides. The horizontal rod thimbles were borrowed on January 2, 1947 to see if any leaks w… more
Date: February 12, 1947
Creator: Montgomery, E. B.
open access

Aerodynamic Characteristics at High Speeds of Full-Scale Propellers Having Different Shank Designs

Description: "Tests of two 10-foot-diameter two-blade propellers which differed only in shank design have been made in the Langley 16-foot high-speed tunnel. The propellers are designated by their blade design numbers, NACA 10-(5)(08)-03, which had aerodynamically efficient airfoil shank sections, and NACA 10-(5)(08)-03R which had thick cylindrical shank sections typical of conventional blades. The propellers mere tested on a 2000-horsepower dynamometer through a range of blade-angles from 20 degrees to 55 … more
Date: February 13, 1947
Creator: Maynard, Julian D.
open access

Analytical Comparison of a Standard Turbojet Engine, a Turbojet Engine with a Tail-Pipe Burner, and a Ram-Jet Engine

Description: From Introduction: "Experimental investigations (reference 1) have shown that in some cases the thrust can be more than doubled by means of tail-pipe burning. A comparison is made of a standard turbojet engine, whose thrust is augmented by tail-pipe burning, and a ram-jet engine. The performance characteristics for the ram-jet engine were computed entirely from theoretical considerations and on the assumption that the burner-inlet velocity was constant."
Date: February 10, 1947
Creator: Krebs, Richard P. & Palasics, John
open access

An Analytical Investigation of the Heat Losses from a U.S. Navy K-Type Airship

Description: From Summary: "The heat losses from the envelope surface of a U.S. Navy K-type airship are evaluated to determine if the use of heat is a feasible means of preventing ice and snow accumulations on lighter-than-air craft during flight and when moored uncovered. Consideration is given to heat losses in clear air (no liquid water present in the atmosphere) and in probable conditions of icing and snow. The results of the analysis indicate that the amount of heat required in flight to raise the surf… more
Date: February 17, 1947
Creator: Hillendahl, Wesley H. & George, Ralph E.
open access

Application of the Analogy Between Water Flow With a Free Surface and Two-Dimensional Compressible Gas Flow

Description: From Introduction: "The development of the measuring apparatus and techniques is presented herein. The application of the analogy to flows through nozzles and about circular cylinders at subsonic velocities extending into supercritical range is also presented."
Date: February 1947
Creator: Orlin, W. James; Lindner, Norman J. & Bitterly, Jack G.
open access

Bearing strength of some sand-cast magnesium alloys

Description: Report presenting testing to determine the bearing strength characteristics of some magnesium-alloy sand castings and the relation between those and more commonly determined tensile properties. The primary sand-cast magnesium alloys of interest for aircraft design are AM403, AM260, and AM265. Results of all of the tension, compression, and shear tests are provided in tables.
Date: February 1947
Creator: Moore, R. L.
open access

Blackbird Cobalt Deposits, Lemhi County, Idaho

Description: Report from the U.S. Bureau of Mines on exploration of known cobalt ore deposits in Lemhi County, Idaho. Physical features of the area, and properties of the cobalt samples collected are presented. This report includes tables, maps, and illustrations.
Date: February 1947
Creator: Reed, G. C. & Herdlick, J. A.
open access

Calculations of the Supersonic Wave Drag of Nonlifting Wings with Arbitrary Sweepback and Aspect Ratio: Wings Swept Behind the Mach Lines

Description: "On the basis of a recently developed theory for finite sweptback wings at supersonic speeds, calculations of the supersonic wave drag at zero lift were made for a series of wings having thin symmetrical biconvex sections with untapered plan forms and various angles of sweepback and aspect ratios. The results are presented in a unified form so that a single chart permits the direct determination of the wave drag for this family of airfoils for an extensive range of aspect ratio and sweepback an… more
Date: February 21, 1947
Creator: Harmon, Sidney M. & Swanson, Margaret D.
open access

Charts Showing Relations Among Primary Aerodynamic Variables for Helicopter-Performance Estimation

Description: "In order to facilitate solutions of the general problem of helicopter selection, the aerodynamic performance of rotors is presented in the form of charts showing relations between primary design and performance variables. By the use of conventional helicopter theory, certain variables are plotted and other variables are considered fixed. Charts constructed in such a manner show typical results, trends, and limits of helicopter performance" (p. 1).
Date: February 1947
Creator: Talkin, Herbert W.
open access

A Comparison of the Lateral Motion Calculated for Tailless and Conventional Airplanes

Description: Theoretical analysts of lateral dynamic motion of tailless and conventional airplanes was made for fighter and heavy transport. Their reactions to a lateral gust and control power required by each for simple maneuvers were determined and compared. Both types of airplanes require almost identical aileron control power to perform a given maneuver; tailless airplane requires about 1-2 to 1-3 directional control power of conventional airplane. Tailless airplane also shows greatest displacement for … more
Date: February 1947
Creator: Harper, Charles W. & Jones, Arthur L.
open access

Comparison of Wind-Tunnel Predictions with Flight Measurements of the Longitudinal-Stability and -Control Characteristics of a Douglas BTD-1 Airplane

Description: "Low Mach number longitudinal-stability and control characteristics as predicted by use of wind tunnel data from a powered 3/16-scale model are compared with flight test measurements of a Navy BTD-1 airplane. The accuracy of the wind tunnel data and the discrepancies involved in attempting to correlate with flight data are discussed and analyzed. The comparison showed that wind tunnel predictions were, in general, in good agreement with flight test data" (p. 1).
Date: February 13, 1947
Creator: Bunnell, Mort V. & Delany, Noel K.
open access

Computed Performance of a Composite Engine Based on Experimental Data for a Single-Cylinder Conventional Aircraft Engine Converted to Compression-Ignition Operation

Description: Memorandum presenting a determination of the performance of a single-cylinder spark-ignition engine modified to operate on a compression-ignition cycle with a compression ratio of 8.0. Experimental data were obtained at an inlet-manifold pressure of 100 inches of mercury absolute, fuel-air ratios of 0.040 and 0.025, and engine exhaust pressures of 30 to 100 inches of mercury absolute. Results regarding single-cylinder-engine experimental data and full-scale-engine calculations are provided.
Date: February 3, 1947
Creator: McCoy, J. Arnold & Szel, Frank
open access

Computed Temperature Distribution and Cooling of Solid Gas-Turbine Blades

Description: "Computations were made to determine the temperature distribution and cooling of solid gas-turbine blades.A range of temperatures was used from 1500 degrees to 2500 degrees F, blade-root temperatures from 100 degrees to 1000 degrees F, blade thermal conductivity from 8 to 220 BTU/(hr)(sq ft)(degrees F/ft), and net gas to metal heat transfer coefficients from 75 to 250 BTU/(hr)(sq ft)(degrees F)" (p. 1).
Date: February 11, 1947
Creator: Reuter, J. George & Gazley, Carl, Jr.
open access

Control Chart Method Applied to Errors in Radioactive Counting

Description: Abstract: The Control Chart statistical methods, developed by Showhart for the control of quality of manufactured products, are applied to the control of Geiger-Miller counting instruments. Experiments are reported to show the use to the Control Chart method for detecting disturbances in instrumental behavior and for detecting radioactive effects so weak that they are near the limit of detection of the instruments. As a corollary, the control chart can be used to reduce to its practical limit t… more
Date: February 22, 1947
Creator: Schlecht, W. G.
open access

Cooling of Gas Turbines 1 - Effects of Addition of Fins to Blade Tips and Rotor, Admission of Cooling Air Through Part of Nozzles, and Change in Thermal Conductivity of Turbine Components

Description: "An analysis was developed for calculating the radial temperature distribution in a gas turbine with only the temperatures of the gas and the cooling air and the surface heat-transfer coefficient known. This analysis was applied to determine the temperatures of a complete wheel of a conventional single-stage impulse exhaust-gas turbine. The temperatures were first calculated for the case of the turbine operating at design conditions of speed, gas flow, etc. and with only the customary cooling a… more
Date: February 11, 1947
Creator: Brown, W. Byron
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Cooling of Gas Turbines, 3, Analysis of Rotor and Blade Temperatures in Liquid-Cooled Gas Turbines

Description: A theoretical analysis of the radial temperature distribution through the rotor and constant cross sectional area blades near the coolant passages of liquid cooled gas turbines was made. The analysis was applied to obtain the rotor and blade temperatures of a specific turbine using a gas flow of 55 pounds per second, a coolant flow of 6.42 pounds per second, and an average coolant temperature of 200 degrees F. The effect of using kerosene, water, and ethylene glycol was determined. The effect … more
Date: February 11, 1947
Creator: Brown, W. Byron & Livingood, John N. B.
open access

Cyclic Engine Test of Cast Vitallium Turbine Buckets - I

Description: "An investigation was conducted to correlate the engine service performance of cast Vitallium turbine buckets with standard laboratory metallurgical data. Data were obtained from four I-40 turbine wheels of Timken alloy with cast Vitallium buckets. In order to accelerate bucket deterioration, the turbine wheels were subjected to 20-minute cycles consisting of 5 minutes at idle and 15 minutes at rated speed" (p. 1).
Date: February 7, 1947
Creator: Farmer, J. Elmo; Darmara, F. N. & Poulson, Francis D.
open access

Development of Inboard Nacelle for the XB-36 Airplane

Description: From Summary: "A series of investigations of several 1/14-scale models of an inboard nacelle for the XB-36 airplane was made in the Langley two-dimensional low-turbulence tunnels. The purpose of these investigations was to develop a low-drag wing-nacelle pusher combination which incorporated an internal air-flow system. As a result of these investigations, a nacelle was developed which had external drag coefficients considerably lower than the original basic form with the external nacelle drag … more
Date: February 11, 1947
Creator: Nuber, Robert J.
open access

Device for Measuring Principal Curvature and Principal Strains on a Nearly Plane Surface

Description: Note presenting a device which makes possible the measurement of principal extreme fiber bending strains over a circular area with a radius of 0.94 inch with a systematic error on 0.1-inch sheet of the order of 0.00003. Equations are presented for computing median fiber strains from the measured curvatures and strains at the surface and from the thickness of the sheet.
Date: February 1947
Creator: McPherson, A. E.
open access

Drag characteristics of rectangular and swept-back NACA 65-009 airfoils having aspect ratios of 1.5 and 2.7 as determined by flight tests at supersonic speeds

Description: Report presenting tests to determine the effects of sweepback angle and aspect ratio on the drag of an NACA 65-009 airfoil at supersonic speeds. The results indicated that for the range of Mach numbers investigated, increasing the sweepback angle and decreasing the aspect ratio reduced the value of the wing drag coefficient.
Date: February 24, 1947
Creator: Alexander, Sidney R. & Katz, Ellis
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