Quarterly progress report on Accurate Nuclear Fuel Burnup Analysis project.

A potential performance limitation of superheat fuel is the susceptibility of the fuel cladding to low cycle fatigue failure. Two simplified analytical methods are presented to estimate the cyclic lifetime of circular superheat fuel cladding. One failure relation is based on a displacement method. The other failure relation is based on a stress method. These relations were compared with data from the literature, and with data involving damage obtained by Reynolds. A recommended design procedure involving the relations is presented. The technique was applied to the SADE 4B experiment with moderate success. These cycling relations involve only mechanical damage imposed by cycling, with a modification for additional damage caused by radiation; they do not include any other potential performance limiting mechanisms, such as stress corrosion, which are normally factored into the over-all fuel design. This work work done under Task C (Materials Development) of the Nuclear Superheat Project, AEC Contract AT(04-3)-189 - Project Agreement 13.

Data relating to the binary and ternary systems involving beryllium oxide are presented . The survey deals with all available literature up to December 1962.

Tests were run at the General Electric Company, Atomic Power Equipment Department, to determine the burnout conditions for a non-uniformly heated rod in an annular geometry.

From introduction: The Carolinas Virginia Tube Reactor is to be designed as a prototype for a large-scale plant of about 200 megawatts electrical or larger, wherein operation with natural uranium feed material may be feasible but such feed material can only be considered if it is the more economical.

Report issued by the Brookhaven National Laboratory discussing bulk grain irradiators. As stated in the abstract, "this report presents the results of a study to conceive, evaluate, review and estimate costs for a number of suitable designs for a Cobalt-60 Bulk Grain Irradiator; select a preferred type; and establish required criteria for future detail design and construction of the selected concept" (p. ii). This report includes tables, and illustrations.

Abstract: The exhibit shows that colloidal aggregates (10 to 20 mu) of human serum albumin I131 may be used safely by intravenous injection to perform photoscans of the heart, liver, spleen, stomach, and salivary glands in man. Large particle size suspensions (10 to 50 mu) of the same material are being investigated experimentally in animals for scanning the lungs after intravenous injection and the brain following injection into an internal carotid artery. The advantages of this test material are the relatively low radiation exposure to the target organs and the number of organs that may be examined. Radiation exposure is low because of the rapid turnover in the target organs and removal from the body, mainly by urinary excretion, within 72 hours. The mechanism of liver-spleen localization with this organic colloid is the same as for inorganic colloidal radiogold198, namely, rapid removal from the blood by the phagocytic cells of the liver and spleen. However, in contrast to the inorganic colloid, which remains in the phagocytic cells permanently, albumin is digested by proteolytic enzymes and the I131 abel is set free to re-enter the general circulation. With the thyroid blocked, the I131 is excreted mainly in the urine as free …

Abstract: A series of clean critical experiments was performed in the SGR critical facility utilizing 2 wt % enriched, uranium metal, hollow cylinder, fuel elements, in AGOT graphite moderator.

A process was developed in which stainless steel-clad UO2 fuel rods are fabricated by high-temperature coextrusion. The process has a potential of being a more economical method for the preparation of stainless steel-clad UO2 fuel rods than the conventional pellet process. Consequently, it was considered advantageous to evaluate the irradiation characteristics of fuel rods fabricated in this manner. Therefore, 24 coextruded fuel rods were manufactured for evaluation in a reactor. The required amounts of UO2 and clad were soaked in separate containers at 1875 and 760 degree C, respectively. The containers were removed from their respective furnaces and were coextruded in one pass. A force of 450 to 475 tons was used, and a reduction ratio of 18 to 1 was obtained. The coextruded rods were cut to the approximate length, and the ends were sealed with an acid-resistant tape. The carbon steel can covering the stainless steel clad was removed by immersion in 1:1 nitric acid for 20 minutes. The rods were visually inspected, the specified lengths of clad and fuel were obtained by machining, and the correct diameter was obtained by belt sanding. The fabrication of the fuel rods was completed by inserting the plenum support tubes and …

"Work has been done on the adaptation of an electrical probe, developed by Neal for the measurement of local void fractions in mercury-nitrogen flow, to air-water flow. The adaptation is more difficult because of wetting of the probe by water. Various probe shapes and filming agents were employed without great success" (p. 1).

This report summarises all the results obtained to date from a programme on the effects of neutron irradiation on the properties of beryllium metal. Results are presented on changes in density and mechanical properties in material fabricated by various routes and irradiated to fast neutron doses from 1019 nvt to 6 x 1023 nvt and at temperatures in the range 75ºC — 700ºC, Summaries of electron microscopy observations and electrical resistivity measurements, which are reported in more detail elsewhere., are also given, It is concluded that all the observed property changes can be interpreted in terms of the distribution of helium which is produced by fast neutron transmutation reactions in beryllium and that damage due to defect production is negligible for irradiation temperatures of 75ºC and above. Density changes duetoheiium bubble formation are shown to be very small but serious deterioration of mechanical properties can occur. The mechanical property changes and the distribution of helium are shown to be very dependent on material history and on the irradiation temperature. The standard Lucas Heights hot extruded material is shown to retain good mechanical properties for irradiation temperatures above 550ºC but serious loss of low temperature ductility is found to occur for …

The diffusion length of thermal neutrons in beryllium oxide of effective density 2.86 g cm-3 has been measured as 29.9 +- 0.8 cm. Using published experimental values for the diffusion constant of beryllium oxide, a value of [sigma] a = 9.0 +- 0.5 mb is deduced for the effective 2200m/s microscopic absorption cross-section.

Fecal specimens from apparently healthy dogs were inoculated into MK, DK, HeLa, and CP cells. Twenty-six cytopathic agents were isolated in MK, 11 in HeLa, and 4 in CP, but none in DK cells. Neutralization tests indicated that all but one of the viruses were either strains of ECHO type 6 or were closely related to it. Twenty-one of 29 dogs were carrying the virus.

This report is an airphoto analysis of soil types including maps and illustrations.

From Abstract: Report discussing "the effects of developing two-phase flow regimes in a constant-pressure drop system are shown in recorded traces from a fast-response flow transducer: the mass velocity decreases and transfer-surface superheat increases with increasing steam quality."

Summary & Conclusions: "The study presented in this report was directed toward resolving the uncertainties in the design and prediction methods for heat transfer performance as well as toward analyzing certain aspects of the scaling problem."

Report issued by the Brookhaven National Laboratory discussing high-pressured gamma loops. As stated in the introduction, "this latest endeavor involved three test cells, a gamma irradiation pool and supporting equipment, as well as an enlarged high-pressure gamma loop facility" (p. 1). This report includes tables, and illustrations.

Introduction: The object of Project Agreement 22, Task 1, is to develop improved detectors which can operate up to 1000 F for in-core power monitoring. Several ideas have been developed to achieve this goal: (1) root mean square fluctuation voltage measurement of ion chamber signals, (2) thermocouple-type detectors, and (3) fabrication developments.

In-pile loop experiments L-2-15 and L-4-16 were two of a series designed to test the radiation corrosion of Zircaloy-2 and other possible reactor construction materials in UO2SO4 solutions under various conditions of radiation intensities, temperatures, solution compositions, and velocity flow past specimens.

The following quarterly report covers the period during February 16 to May 15, 1963. This report is divided into sections covering the separate activities during this period, studying the thermal behavior of the F-center in RbCl.

From Introduction: "The present study was initiated to provide data regarding the particulate state of fission products released from uranium heated in air. It was expected that the information gained in this work would be valuable in planning experiments in which animals would be exposed to aerosols of mixed fission products and in determining the feasibility of using the effluent from a fuel specimen melt-down or oxidation in such exposures."

From Introduction: "The purpose of this paper is to shed additional light on the techniques of a Second Law Analysis. The stimulus for writing this paper came from questions asked and difficulties that occurred during lectures on the subject at the graduate level. This paper utilizes Keenan's basic approach but presents the material with emphasis upon a clear definition of the work associated with each subsystem in the process."

The design of prestressed concrete pressure vessels is discussed and some approximate design formulae are developed. The design and performance of vessels reported in the literature are reviewed and an approximate comparison is made of steel and concrete pressure vessels for a particular case. Concrete vessels are attractive for moderate temperatures and pressures because of the large size of vessel which can be built and the non-explosive mode of failure. However it is unlikely that large cost savings will be made by using prestressed concrete instead of steel for the pressure vessels.

Report containing experiments conducted at the Oak Ridge National Laboratory's Critical Experiments Facility. These experiments involved "determining the critical parameters of the assembly with varying amounts of neutron absorber in the D20 reflector, measuring the relative neutron flux distribution for various conditions of reflector poison and fissile solution concentration, determining the ratio of the absolute thermal-neutron flux in the center of the assembly to the power in the fissile solution , and determining the effect on reactivity of reducing the hydrogen density in the central region of the assembly" (p. 1).