This document presents the monthly reports of the 200 area technical group for July--December, 1947. (KS)

Column and plate compressive strengths of extruded 0-1HTA magnesium alloy were determined both within and beyond the elastic range from tests of flat end H-section columns and from local instability tests of H-, Z-, and channel section columns. These tests are part of an extensive research investigation to provide data on the structural strength of various aircraft materials. The results are presented in the form of curves and charts that are suitable for use in the design and analysis of aircraft structures.

Note presenting three temperature-height relationships and one composition-height relationship developed by the NACA and tables based on them for pertinent properties of the upper atmosphere. Two sets of tables based on the adopted tentative standard specifications for the upper atmosphere are presented.

Results are presented of tests to determine the effect of brake forming in various tempers on the strength of Alclad 75S-T aluminum alloy sheet in the direction parallel to the brake. The tensile and compressive strengths of Alclad 75S-T sheet, formed in the O and W tempers, were either increased or little affected compared with those of similarly treated unformed material. When Alclad 75S-T sheet 'as received' was formed, however, the tensile yield stress was reduced about 7 percent for the with-grain direction and 1 percent for the cross-grain direction, whereas the tensile ultimate and compressive yield stresses were increased somewhat. The elongation was always slightly reduced as a result of forming.

This technical progress letter contains reports from six Technical Department divisions at the Hanford Engineer Works for January 19 through January 25, 1947. The six reporting divisions are: 100 Areas, 300 Area, 200 Areas, Chemical Development, Laboratories, and Statistical Studies. (JL)

The thirteenth meeting of the Graphite Expansion Committee was held on January 10, 1947. A summary of meeting topics follow. The horizontal bowing of Tube 4494-D in the top corner of the pile is considerably greater than the bowing which can be attributed to graphite expansion at this elevation in the pile, indicating that the top layers of graphite are being dragged outward by expansion of the underlying layers. Such a phenomenon could shear the vertical thimbles at a point just below the thermal blocks. Equipment is to be developed for measuring any eccentricity between the rod guide and a section of the thimble located just below the end of the guide. Jacking tests using forces up to 4000 lbs. on gun-barrels which show binding have demonstrated that binding is still present at these high forces. It was recommended that no further jacking tests be performed on gun-barrels which are known to exhibit binding. Rupture tests on Tube 4082-B caused failure of the rear Van Stone joint after the tube had been stretched {1/2} inch. The amount of tube stretch before failure of the flames will probably be affected primarily by corrosion of the flange and, for the same reason, …

This report summarizes physics experiments carried out in different parts of the 100 area at Hanford during December, 1946. This included work on the D pile, F pile, and experiments aimed at studying the irradiation properties of graphite and metal samples exposed to different radiation environments. Pile tests included reactivity tests, calibrations of control rods, and power coefficient tests.

The face to face expansion of the graphite packing of the pile reduces the gun barrel sum-clearance and if continued will strain the aluminum tubes with ultimate rupture of the Van Stone joints. The graphite expansion may be determined while an aluminum process tube is out of the unit. The distance from the graphite at the inner end of one gun barrel to the corresponding point at the opposite face is measured and compared to a similar measurement that was made during construction of the pile. The replacement of the two scored aluminum tubes at F Pile provided an opportunity to make these measurements. A corresponding measurements made during construction indicates an expansion of 28/32in. at Tube 2174-F and 23/32in. at 2284-F on November 5, 1946, after a total pile exposure of 132,896 MWD. Measurements of gun barrel sum-clearance and aluminum tube length before replacement indicated a graphite expansion of 25/32in. at Tube 2174-F and 24/32in. at 2284-F, which is in reasonable agreement with the above graphite measurements.

Prior analyses of a plasma in a magnetic field have been limited, as far as the writer is aware, to cases in which the relative change in field over the orbital distance and the relative change in ion concentration are both small, or in which the relations have been viewed in a purely hydrodynamical way. The first approach excludes cases which can be of considerable interest, for it fails for a plasma edge. The second loses all sight of the structure imposed by the orbital motions.

Abstract: Solid ferric chloride reacts with solid uranium tetrachloride to form a complex iron-uranium chloride compound at approximately 263°C. The vapor pressure of this compound is nearer to that of uranium tetrachloride than to the vapor pressure of ferric chloride.

This report discusses two methods used for experimental determination of the interfacial tension of an immisible aqueous-organic system where the density of the organic phase is less than that of the aqueous phase. The methods discussed are the falling drop method and the Donnan modification/rising drop method.

This report for January, 1947 discusses progress regarding ore dressing studies, pyrometallurgical work, chemical work, chemical and spectrographic analysis, and physical methods of analysis.

From introduction: "The purpose of this report is to summarize some of the information obtained to date on the distribution of the uranium in the mineral phases of the phosphate rocks and shale."

Note presenting pressure distributions and force measurements in the two-dimensional low-turbulence pressure tunnel at low Mach numbers and high Reynolds numbers of an NACA 65-210 airfoil equipped with a 50-percent-chord plain flap. Tests were carried out for flap deflections of 0, 4, 7, and 10 degrees. These flap deflections provided considerably reduced drag coefficients at life coefficients above the design range of the plain airfoil.

Report presenting an extension of previous work on the theory of self-excited mechanical oscillations of hinged rotor blades. This particular report details the missing case of one or two blades on unequal supports. Results regarding types of instability, general behavior of rotor system as a function of rotor speed, and effect of damping is provided.

Strain measurements and strength tests were made on six skin-stringer panels under axial load. Three of these panels had short rectangular cut-outs, and three a long one. The width of the cut-out was about one-half of the width of the panel. Three types of coating stringers were used: without reinforcement, with riveted-up reinforcement, or with integral reinforcement. The strain measurements were found to be in good agreement with a previously published theory adapted where necessary by making overlapping assumptions.

From Summary: "Strength tests were made of a number of 24S-T and Alclad 75S-T aluminum alloy shear webs to determine the effect of rivet or bolt holes on the shear strength. Data were obtained for webs which approached a condition of pure shear stress as well as for webs with well-developed diagonal tension. The rivet factor (pitch minus diameter), divided by pitch, was varied from approximately 0.81 to 0.62. These tests indicated that the shear stresses on the gross section were nearly constant for all values of the rivet factor investigated if the other properties of the web were not changed."

Report presenting a consideration and evaluation of the effects of several parameters on the drag characteristics of practical construction wing sections. The effects considered were those of surface roughness, surface waviness, compressive load, and de-icers.

The shock expansion method of the NACA TN No. 1143 was used to determine the principal aerodynamic characteristics of two-dimensional supersonic airfoils. A discussion is given of the effect of thickness ratio, free-stream Mach number, angle of attack, camber, thickness distribution, and aileron deflection. The calculations indicated that the minimum drag of supersonic airfoils is obtained when the maximum thickness is behind the 0.50 chord. The center of pressure obtained for a symmetrical supersonic airfoil was found to be ahead of the 0.50 chord.

Solutions of the Hugoniot shock equations and Meyer expansion equations are plotted in such a manner as to permit the pressure distribution, the local Mach number, and the angles of shock waves on arbitrary sharp-nose airfoils at supersonic speeds to be obtained directly. (author).

Report presenting an investigation of the lateral-control characteristics of several spoiler arrangements located near the wing trailing edge in flight. In all cases, the control response was satisfactory and the variation of rolling effectiveness with control deflections was smooth and nearly linear. Results regarding response characteristics, rolling effectiveness, control-force and hinge-moment characteristics, yawing characteristics, effects of altitude, characteristics near the stall, and characteristics in inverted flight are provided.

Report presenting measurements of the velocity distributions at the outlet of a large number of duct elbows of round and elliptical as well as square and rectangular cross section at a range of Reynolds numbers. Special investigations include measurements of the decay of velocity patterns produced by curved ducts and the effect of asymmetrical upstream velocity distributions. Results regarding typical distributions, tabulation of principal results, and special investigations are provided.

"A device has been developed which measures the velocity of sound in fluids at stagnation and is especially adaptable to turbine and compressor testing for which the constituency of the working fluid may be in doubt. By utilizing the shaft frequency of a rotary compressor, the instrument can also be used to provide a direct measurement of the compressor Mach number (ratio of blade-tip velocity to inlet velocity of sound at stagnation). A Helmholtz resonator is employed in the measurement of the sound velocity" (p. 1).

Report presenting a method for predicting the stability of automatically controlled aircraft by comparing the calculated frequency-response curves for the aircraft and experimentally determined frequency-response curves for the automatic pilot. The method is applicable only to stabilization in roll. It can be used to establish the specifications of performance required for the automatic control device for pilotless aircraft designed as missiles.