This report details 100 Area reactor operation for the time period of August 6 through August 12, 1946.

Work of the pile physics and experimental physics groups is reported. Theoretical work is also reported.

None

None

"A study of the data obtained in a flight investigation of an R-2800-21 engine in a P-47G airplane was made to determine the effect of the flight variables on the engine cooling-air pressure distribution. The investigation consisted of level flights at altitudes from 5000 to 35,000 feet for the normal range of engine and airplane operation. The data showed that the average engine front pressures ranged from 0.73 to 0.82 of the impact pressure (velocity head). The average engine rear pressures ranged from 0.50 to 0.55 of the impact pressure for closed cowl flaps and from 0.10 to 0.20 for full-open cowl flaps" (p. 1).

An investigation on various can-type burners in a Bumblebee 18-inch ram jet under controlled conditions of pressure altitude and ram pressure ratio was conducted in the NACA Lewis altitude wind tunnel with kerosene as fuel. The performance of the following can-type burner configurations was better than that of the other burner configurations investigated: (1) a flame holder having a two-pitch alinement of perforations, 0.07-inch-wide cooling slots, and an arrangement of fuel nozzles located within an annulus having a mean radius of 7.24 inches; and (2) a flame holder having a zero-pitch alinement of perforations, 0.16-inch-wide cooling slots, and an annulus of fuel nozzles having a mean radius of 6.89 inches.

"Finally the work of the report is applied exclusively to consideration of the turbine-propeller power plant because previous performance analyses of the various gas-turbine propulsion systems combine with recent improvements in propeller design indicate that it is this combination which, will give the best over-all performance in the speed ranges considered" (p. 5).

Flow-metering devices used by the NACA and by the manufacturer of the J33 turbojet engine were calibrated together to determine whether an observed discrepancy in weight flow of approximately 4 percent for the two separate investigations might be due to the different devices used to meter air flow. A commercial adjustable orifice and a square-edge flat-plate orifice used by the NACA and a flow nozzle used by the manufacturer were calibrated against surveys across the throat of the nozzle. It was determined that over a range of weight flows from 18 to 45 pounds per second the average weight flows measured by the metering device used for the compressor test would be 0.70 percent lower than those measured by the metering device used in the engine tests and the probable variation about this mean would be +/- 0.39 percent. The very close agreement of the metering devices shows that the greater part of the discrepancy in weight flow is attributable to the effect of inlet pressure.

Abstract. In the first section of this technical report a new method of extracting uranium from thorium nitrate solution is discussed. This method consists of extracting an aqueous solution of thorium nitrate, nitric acid, sodium sulphate, and potassium thiocyanate with hexone. By this procedure, using an equal volume of hexone it is possible to extract 83 percent of the uranium while only 0.3 percent of the thorium is extracted. other experiments show that even greater separations are possible. In the second section of this report the use of antipyrine in solvent extraction procedures is discussed. Experiments are described in which 90 percent of the uranium is extracted while the thorium is extracted to the order of 3 to 5 percent.

Abstract: "Small amounts of acetic acid, equivalent to 400 ul. of 0.3 to 0.13 g/L. can be titrated coulonatrically in the presence of a 10 to 25-fold excess of HN03 in 70%, isopropanol. An accuracy of +/- 0.1% and a precision of +/- 8.5% (99% limite) are obtained.

Abstract: "A new method of determining 8-hydroxyquinoline by titration with electrolytucally-generated bromine has been developed. Results show good precision in the range 0.4 mg. to 1.6 mg. total 8-hydroxyquinoline, with 99% confidence limits of less than +/- 2%. An electronically-regulated constant current source, required by the method, is described. A new indicator system with high sensitivity to free bromine is discussed."

Partial abstract: "The investigation of the high temperature and pressure dissociation of water under irradiation was undertaken by the Power Pile Division of Oak Ridge National Laboratory in an effort to determine the degree of importance of the phenomenon with respect to the design of a high temperature water-cooled power reactor. Theory and past experimentation indicate that net steady-state dissociation is determined by the rates of the dissociation and recombination reactions under the imposed conditions, the dissociation rate being essentially a function of flux and the recombination rate essentially a function of temperature" (p. 3).

"Detail calculations are presented of the shifts in stick-fixed neutral point of the Republic XF-12 airplane due to the windmilling propellers and to the fuselage. The results of these calculations differ somewhat from those previously made for this airplane by Republic Aviation Corporation personnel under the direction of Langley flight division personnel. Due to these differences the neutral point for the airplane is predicted to be 37.8 percent mean aerodynamic chord, instead of 40.8 percent mean aerodynamic chord as previously reported" (p. 1).

From Summary: "The trajectories of waterdrops in air flowing over airfoils are determined for three airfoil-angle-of-attack combinations using the differential analyzer to solve the differential equations of motion of the waterdrops. From these trajectories the rate of water impingement, the area of impingement, and the distribution of impingement are determined as functions of two dimensionless moduli. Comparisons are made of the rate of water impingement on these airfoils and the rate of water impingement on cylinders."

From Summary: "The trajectories of waterdrops in air flowing over airfoils are determined for three airfoil-angle-of-attack combinations using the differential analyzer to solve the differential equations of motion of the waterdrops. From these trajectories the rate of water impingement, the area of impingement, and the distribution of impingement are determined as functions of two dimensionless moduli. Comparisons are made of the rate of water impingement on these airfoils and the rate of water impingement on cylinders."

"The trajectories of waterdrops in air flowing over airfoils are determined for three airfoil - angle-of-attack combinations using the differential analyzer to solve the differential equations of motion of the waterdrops. From these trajectories the rate of water impingement, the area of impingement, and the distribution of impingement are determined as functions of two dimensionless moduli. Comparisons are made of the rate of water impingement on these airfoils and the rate of water impingement on cylinders" (p. 1).

Inroduction: "A study of the literature, particularly the work done by R. Strubl, I.W. Kolthoff and S.B. Smith, indicated that a polargraphic method for the estimation of T could be devised which would not sacrifice reasonable accuracy for rapidity. Work was begun with the intention of developing such a method."

"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).

Abstract: "Diameter measurements of 25 slugs taken before and after a prolonged heat treatment showed no evidence of differences that would indicate blistering. The average effects of the treatment was different for the various slugs. Large differences in diameter measurements between slugs. Large differences in diameter between slugs and significant differences between indices and positions were found."

Exploratory tests are reported which indicate the feasibility of a one-step reduction process for the preparation of uranium metal from the hexafluoride by the action of calcium metal and iodine.

"The ditching characteristics of the Army B-36 airplane were determined by testing 1/20- and 1/30-scale dynamic models in calm water in Langley tank no. 2 and at the outdoor catapult. The scope of the tests consisted of ditching the models at various conditions of simulated damage, landing attitudes, and speeds, with various flap settings using several degrees of restraint of the flap hinges. The ditching behavior was evaluated from recordings of deceleration, length of run, and motions of the models" (p. 1).

An extended form of the Ackeret iteration method, applicable to arbitrary profiles, is utilized to calculate the compressible flow at high subsonic velocities past an elliptic cylinder. The angle of attack to the direction of the undisturbed stream is small and the circulation is fixed by the Kutta condition at the trailing end of the major axis. The expression for the lifting force on the elliptic cylinder is derived and shows a first-step improvement of the Prandtl-Glauert rule. It is further shown that the expression for the lifting force, although derived specifically for an elliptic cylinder, may be extended to arbitrary symmetrical profiles.

Report discussing an investigation on the effect of engine skew on the directional and lateral control characteristics of a single-engine airplane with a single-rotating propeller. The estimated and test results showed an advantage to skewing the propeller, as it assists with overcoming inadequate rudder control in power-on flight and aileron control, especially with flaps deflected.

Report presenting the results of an analytical investigation, which demonstrated that the inlet of a turbojet engine can be protected from ice accretions by bleeding hot gases from other locations within the engine to the inlet without undue loss in thrust. Results regarding the bleedback requirements, engine performance, effect of nozzle area, mixing efficiency, and seriousness of thrust losses are provided.