Memorandum presenting the buffet characteristics of a scale model of an attack airplane over a range of Mach numbers. The wing had a modified delta plan form with an NACA 0008 airfoil section at the root and an NACA 0005 airfoil section at the tip, a leading-edge sweep of 41.11 degrees, an aspect ratio of 2.91, and a taper ratio of 0.226. Results regarding the frequency spectrum of bending moment, effect of density on root-mean-square bending moment, system damping coefficients, and buffet input force are provided.

Report presenting an investigation of the buffet characteristics of a model of an attack airplane at a variety of Mach numbers. The wing had a modified delta plan form with two NACA airfoils, a leading-edge sweep of 41.11 degrees, an aspect ratio of 2.91, and a taper ratio of 0.226. Results regarding frequency spectrum of bending moment, effect of density on root-mean-square bending moment, system damping coefficients, and buffet input force are provided.

"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 angle for stream Mach numbers up to a value corresponding to that at which the Mach line coincides with the wing leading edge. The calculations showed that in general the wave-drag coefficient decreased with increasing sweepback" (p. 1).

From Abstract : "The solubilities of the individual rare earth lactates and α-hysroxyisobutyrates in water at 20 and 60° were determined for comparison with the rare earth glycolate solubilities determined earlier."

From abstract: "The purpose of this note is to consider the feasibility of conducting kiloton-weapons tests in underground holes sufficiently deep so that the explosion will be effectively contained. Such a shot would have the advantage that it could be detonated independently of weather conditions, and thus would allow greater freedom in the test program."

A relationship is derived the mean square fluctuating current of a hot wire anemometer and the sic turbulent Reynolds stresses in the stream-coordinate system without employing the usual low turbulent intensity approximation. The relatively simple result is a consequence of assuming proportionality between the wire current reading and the perpendicular velocity component instead of the non-linear dependence required by King's law. The assumption is valid for instruments equipped with the proper linearizing circuitry. The stream-coordinate Reynolds' stresses are then related to the cylindrical polar Reynolds stresses.

Observations of the effects of neutron damage to zirconium oxides led to the conclusion that the cubic form of ZrO2 is more stable to such damage than the monoclinic form. It has been reported that zirconium corrodes more rapidly in certain liquids when exposure is made under radiation (neutrons and fission products). It is well known that on heating monoclinic ZrO2 a transformation, monoclinic to tetragonal (very similar to cubic), occurs at about 1500°C. The transformation involves sufficient atomic rearrangement that pieces of ZrO2 normally crack and crumble. It is suggested that the effects of neutrons on monoclinic ZrO2 may be similar so that a protective oxide film on the metal would be destroyed soon after its formation. It might be possible, therefore, that the protective oxide film on zirconium metal which is normally monoclinic might be less resistant to corrosion under radiation damage than a similar film which was cubic.

The calibration of mercury vapor detectors has always posed a problem because of the difficulty of generating known concentrations of mercury vapor in air. The purpose of this study was to design an apparatus that would generate and chemically measure known concentrations of mercury vapor in air for calibration work.

Report presenting an investigation of the effects of three centrally mounted wing-tip tanks on the aerodynamic characteristics of a cambered wing with an aspect ratio of 10 and 35 degrees of sweepback. Testing occurred over a range of Mach and Reynolds numbers and lift, drag, and pitching-moment were measured.

Report presenting a continuous sampling-probe technique used to determine the percentage of JP-5 fuel spray evaporated under conditions common in ramjet engines. Fuel was injected contraststream from a multiple-orifice injector and sampling data were obtained at several distances downstream of the injector. An expression is generated for a description of this phenomenon.

An investigation was made to determine the effects of varying the spacing between the nozzle blades and the turbine blades of a turbo-jet engine on turbine-blade vibration for four turbine-blade designs of different degrees of stiffness. In general, there was a tendency toward increase in occurrence of vibration with decrease in spacing. The effect was most evident in the case of the turbine blades that had greater stiffness.

"An investigation of the static and dynamic longitudinal stability characteristics of 1/3.7 scale rocket-powered model of the Bell MX-776A has been made for a Mach number range from 0.8 to 1.6. Two models were tested with all control surfaces at 0 degree deflection and centers of gravity located 1/4 and 1/2 body diameters, respectively, ahead of the equivalent design location. Both models were stable about the trim conditions but did not trim at 0 degree angle of attack because of slight constructional asymmetries" (p. 1).

A method for calculating the frequency response of weighted voids (proportional to reactivity of steam voids) as a function of reactor power is presented.

This report considers the HFIR reflector design criteria and presents a summary of the reflector design. The reflector type chosen as complying best with the established criteria consists of a 3 in. thick removable beryllium annulus utilizing four concentric cylinders with cooling water flowing through the annuli between cylinders, and an outer 9 in. thick permanent beryllium annulus with axial circular coolant holes. Reflector support structures and experimental facilities are described and probable beryllium replacement costs are indicated.

This report is presented in order to provide a satisfactory system of symbols and identifications for process-instrumentation equipment and to promote a uniformity of practice that will simplify and expedite instrumentation work. It is intended that the systems presented here should be capable of designating and identifying the multitude of instrumentation items which are used for control and operation of conventional processes, as well as for specialized work peculiar to ORNL. Instrument Society of America standards have been adhered to whenever practical.

To date, three types of metal-to-metal seal disconnects have been subjected to thermal cycling and make-break tests. In addition, a commercial disconnect has been procured for testing.

Memorandum presenting an investigation in the 4- by 4-foot supersonic pressure tunnel to determine the effects of various vertical locations of the wing and horizontal tail on the aerodynamic characteristics in pitch and of a supersonic airplane configuration at Mach number 2.01. The model was equipped with a wing and horizontal tail, each having a 45 degree sweep and an aspect ratio of 4. The configurations investigated included a high-wing, a mid-wing, and a low-wing arrangement, each with four different horizontal tail locations varying from a position 0.208 semispan below to 0.556 semispan above the body center line.

Report presenting an investigation of the performance of the Westinghouse XJ34-WE-32 engine with afterburner operative in the altitude wind tunnel at a range of simulated altitudes and Mach numbers. A study was also made to prevent the clogging of the fuel-injection holes due to coke or carbon deposits, which occurred during initial testing. Results regarding the characteristics of fuel manifold coking, influence of fuel distribution on performance, afterburner inlet conditions, effect of altitude and flight Mach number, afterburner pressure losses, and afterburner ignition and blowout are provided.

"An investigation was conducted to compare the knock-limited performance of a 20-percent triptane blend in 28-K fuel with that of 28-R and 33-R fuels at high engine speeds, cruising speeds, and two compression ratios in an K-1830-94 multicylinder engine. Data were obtained with the standard compression ratio of 6.7 and with a compression ratio of 3.0. The three fuels were investigated at engine speeds of 1800, 2250, 2600, and 2800 rpm at high and low blower ratios" (p. 1).

Report issued by the Oak Ridge National Laboratory discussing quarterly progress made by the Molten-Salt Reactor Program. Descriptions of the progress and studies conducted is presented. This report includes tables, illustrations, and photographs.

The four types of respirator cartridges used at the 202 S Building were tested against aerosols found at that location, and in the laboratory against non-radioactive gaseous ruthenium tetroxide. Positive penetration of two types of cartridges was shown with one process aerosol. Gaseous ruthenium tetroxide penetrated all types of cartridges tested. Leaks were found in some of the cartridges. Particle size of aerosol particles was measured by means of cascade impactor samples and electron photomicrographs. A high percentage of the aerosol particles was found to be less than 0.2 microns in diameter. Ru¹⁰³ + Ru¹⁰⁶ and Zr⁹⁵ + Nb⁹⁵ were shown to be present in the process aerosol by gamma ray spectrometer analysis. Possible causes of penetration of respiratory equipment by ruthenium are discussed and suggestions made for alleviating the problem.

Report presenting the results of a series of exploratory flights on a 35 degree swept-wing airplane up to Mach number 1.09 to show the effects of compressibility on imposing maneuverability limits. Results regarding the maneuvering accelerations and buffet boundary are provided.

Report presenting testing of a series of thin, triangular plan-form wings, including eight triangular wings of vertex angles and three swept-back wings with circular-arc sections. Results regarding lift, center of pressure, and ideal operation of different types of wings are provided.

Report discussing the status of ductile zirconium preparation by the National Research Corporation up to February 20, 1950.