A method of determining enclosure pressure in the event of a reactor rupture is presented and a sample calculation is shown. This method was used in calculating the design pressure of the Dresden Nuclear Power Station enclosure.

A two and one-half year period of extreme caution where titanium and nitric acid are involved has passed since the occurrence of the last and most serious uncontrolled incident involving titanium and nitric acid. During this period controlled explosions involving titanium and nitric acid have been routinely reproduced, additional laboratory and pilot plant experience has been gained and successful industrial applications have been appraised. Based on laboratory data and the known industrial experiences, it is concluded that titanium can be safely employed in systems handling nitric acid that contains more than two (2) percent water. It is recommended that the titanium heat exchanger recently fabricated by the Technical Shops be installed in the Purex Plant plutonium concentrator when replacement of the stainless steel unit now in service becomes necessary.

The introduction of aluminum in hot process water has been studied extensively and numerous reports have been issued on the subject. The conclusions reached have been largely empirical and can only be used to state what is happening under the given conditions existing in the corrosion experiments. It is only with difficulty and a great deal of uncertainty that these empirical results can be used to predict what will occur under a different set of conditions. If the fundamental mechanism of aluminum corrosion in water were known, it is possible that more accurate predictions could be made and that steps might be taken to affect the controlling factors and thus reduce the severity of corrosion. To keep the system as simple as possible one would attempt to study the corrosion mechanism by corroding aluminum in pure water. However, this is undesirable because of the extremely low corrosion rate of aluminum in pure water and the large water supply and treatment facility required to supply sufficient high purity water for circulation about the corrosion samples.

This paper discusses technical bases, operating standards, and instrumentation systems required to achieve the goal of nuclear safety in operation of high-level reactors. Because of the relatively long neutron lifetime in a thermal reactor and the comparatively modest time rates of reactivity change associated with fission poison and temperature effects, the rod system used for compensating reactivity transients and for maintaining flux distribution control may be operated manually. Manual operation of the reactor and the prediction of pile reactivity statue during outages of course involve factors of human error, normal reaction time, and judgment. It is the aim to specify procedures for the operation such that manual control of the reactor may be adequately maintained at all times within the range of reasonably expected calculational errors and human reaction times. The technical considerations used in developing these standards, including the available monitoring indications are discussed first; then the automatic trip devices which should back up the procedures are also mentioned.

At the request of F. W. Albaugh of the Engineering Department, the corrosive effect of 1% uranium nitrate hexahydrate solution on aluminum at 100 C has been measured. The corrosion of aluminum in uranium nitrate solution has been shown in laboratory tests to be too severe to permit the use of aluminum for containing hot uranium nitrate solutions. A minimum corrosion penetration rate of 2 mils per day was observed with M-329 aluminum in 1% uranium nitrate hexahydrate in pH 2 aqueous solution at 100 C.

The stability of fluorothene (polytrifluorochloroethylene, Kel-F) to gamma radiation has been investigated to estimate the probable life expectancy of fluorothene equipment exposed to Purex process solutions. Samples of fluorothene were exposed to total gamma radiation dosages up to 10 degree R. The results of these tests substantiate the findings reported by Sisman and Bopp in their compilation of data on the affects of radiation on plastics.

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This report addresses the progress report of ANP chemistry for April 1956.

An LCAO molecular orbital calculation using the full six-electron hamiltonian has been per formed on Li2 a t a nuclear separation equal to 'the experimental internuclear distance. The molecular wave function consisted of one antisymmetrized product made up of molecular orbitals formed as the best linear combinations of Slater Is, 2s, and 2p atomic orbitals. The orbital exponents for these atomic orbitals were respectively 2. 69, 0.64 and 0. 53 as determined by a variational calculation on the lithium atom. In computing the molecular dissociation energy, the .energy of two separated lithium atoms was taken to be that obtained by this variational calculation. The computed dissociation energy was found to be 0. 33 ev compared with the experimental value of 1. 05 (where a slight correction for zero-point energy has been made). The ratio of the computed molecular ground-state energy to the experimental is 0. 9902 while the difference of these quantities is 4. 00 ev. Certain other molecular constants are calculated and compared with available experimental data.

This report talks about Chemical Development Status Report for Week Ending June 1, 1956

To reduce manpower burn-out rates resulting from contamination on tools and equipment which are used to remove process tubes, a method for decontaminating, evaluated. The referenced document reported the results of a small scale test designed to remove film from inside the process tube prior to removal of the tube from the reactor. A more conclusive test was also outlined. The purpose of this document is to report the results of the larger scale test.

This report discusses the installation of operational charge-discharge equipment on the Hanford reactors has been proposed as a means of eliminating the reactor downtime required for charging and discharging the metal in the reactors. Additional benefits such as the minimization of the effects of slug ruptures, improved reactivity control, and improved metal utilization have become apparent during the investigation of the use of the equipment. Since the minimization of the effects of ruptures has been considered only qualitatively in previous justification documents for operational charge-discharge, the purpose of this document is to evaluate quantitatively the effect of such equipment on operation with a slug rupture limit.

From page 2: "This article first describes the Bevatron [particle accelerator] and its operation, and then discusses a portion of the research program. The principles of the machine and its early history were given in "The Bevatron," by Lloyd Smith, Scientific American, February 1951."

Report discussing methods for recovering hafnium-free zirconium from irradiated fuel elements. Two methods are discussed: the fluoride method and the Zircex method. Experimental procedures to evaluate these methods and their results are presented.

Abstract: "This specification covers the cleaning of Zir caloy-2 components of PWR fuel rods and such tools, gauges, or other devices as may be required in subsequent handling, welding and inspection per Fuel Rod Specification AP-292545, Section II-A-4 and Section II-B-3."

The continuation of a study of pressure drop across various combinations of staggered multihole orifice plates in series is described. Plates used in this test contained bevelled leading edge holes and were of the general design proposed for fiow control in the PWR blanket region. Variables examined in this test were orifice diameters of 0.300, and 0.625 in., one to six plates in series, and flow rates corresponding to orifice Reynold's numbers ranging from 15,000 to 140,000. The orifice plates and experimental methods employed in this test were similar to those described in the preceding orifice plate report. WAPDTH-241 (41 holes on a 0.486 in. square pitch located in a 4.195 in. diameter pipe), with the exception that the present plates had a 3O deg bevel around the leading edge of each hole sufficient in depth to make the bevelled diameter 1/16 in. larger than the hole diameter. Results are given as pressure loss coefficients (number of orifice velocity heads), and were found to be about 50% less than comparable values for squarc edge orifices. In general, Reynolds's number had no effect upon the loss coefficients. The loss coefficients are estimated to be accurate within plus or minus 10% over …

A sprawling group of buildings on an impressive campus site in the Berkeley hills provides the home of the Radiation Laboratory of the University of California. A succession of large accelerators has been built there, the latest of which is the Bevatron. It is the largest and highest-energy accelerator in operation at the present time. It was built and is operated under contract with the United States Atomic Energy Commission. It is of the type known as a proton synchrotron, of which there are two others in operation, one at the University of Birmingham, England, whose energy is 1 Bev (billion electron volts), and another at the Brookhaven National Laboratory, known as the Cosmotron, which operates at 3 Bev. The Bevatron accelerates protons (stripped nuclei of hydrogen atoms) to an energy of 6.2 Bev. The design was started in 1947 under the direction of Professor E. O. Lawrence, and although it was the product of collaboration of a large group of physicists and engineers, the original conception was due to William Brobeck who also contributed more than any other individual. A working quarter-scale model was built and operated in 1948 and 1949 to verify the correctness of the design concept. …

Report presenting an investigation of the hydrodynamic characteristics of a powered dynamic model of the Martin PBM-5 seaplane equipped with a single Edo hydro-ski. Various hydro-ski positions were investigated. Results regarding aerodynamic and hydrodynamic characteristics, including excess thrust, smooth-water landings, smooth-water take-offs, rough-water take-offs, and spray are provided.

Report presenting a determination of the combustion efficiency of gaseous hydrogen fuel in a ramjet engine in a connected-pipe test facility. Operating conditions simulated a range of Mach numbers and altitudes. Results regarding the effect of inlet parameters and design variables on combustion efficiencies, comparison between methods of determining efficiency, and ignition characteristics are provided.

Report presenting an evaluation of data obtained with an automatic constant inlet-pressure control valve designed to facilitate the study of transient engine performance characteristics in the altitude wind tunnel. The engine characteristics obtained by use of the pressure valve were compared with those obtained with a bellmouth inlet operating in simulated free-stream conditions.

Report presenting an investigation of an exhaust jet and elementary contoured surface at Mach number 1.6 over a range of nozzle pressure ratios from jet-off to a pressure ratio of 9. The effect of the presence of streamline fairings between the surfaces and parabolic afterbody housing the exhaust nozzle on the interaction was also investigated.

Report presenting a determination of the relative reactivities of six fuels with red fuming nitric acid in a 40-pound-thrust rocket engine with rapid liquid-phase mixing. Hydrazine, trimethyl-trithiophosphite, furfuryl alcohol, unsymmetrical dimethylhydrazine, allylamine, and o-toluidine were studied. Results regarding the combustion characteristics of the fuels, fuel ratings, pressure in the mixing cup, effect of chamber diameter, and overall combustion efficiency are provided.

Memorandum presenting a study of several typical air induction systems for modern aircraft, which indicates that flow distortions of about-pipe-flow magnitudes can be expected at near-optimum inlet-engine matched air-flow conditions and at small angles of attacks. The distortions may be seriously increased by operation at large angles of attack or yaw, or by supercritical operation of the inlets. Boundary-layer bleed, duct overexpansion and contraction, and freely rotating fans appear promising as devices for reducing distortions with little cost in propulsive thrust.

An annular prevaporizing turbojet combustor having pressure losses lower than those obtained in current turbojet combustors was developed, Pressure losses of 2 to 4 percent, satisfactory temperature profiles, and combustion efficiencies of 98, 88, and 81 percent were obtained at 56,000, 70,000, and 80,000 feet respectively, for a simulated 5.2- pressure-ratio engine at rated speed and 0.6 flight Mach number with JP-4 fuel. Use of JP-5 fuel resulted in a small penalty in efficiency due, at least in part, to insufficient prevaporizer capacity.