UNT Libraries Government Documents Department - 288 Matching Results

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Accurate Nuclear Fuel Burnup Analyses; Eighth Quarterly Progress Report, (September - November 1963)

Description: The objective of the Accurate Nuclear Fuel Burnup Analyses program is to develop more accurate methods for burnup analysis for general use than the current method of analysis of Ca-137 or Sr-90. The program will require from three to five years of effort.
Date: December 1, 1963
Creator: Rider, B. F.; Ruiz, C. P.; Luke, P. S., Jr.; Peterson, J. P., Jr. & Smith, F. R.
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Advanced Designs and Special Applications for Fast Breeders

Description: The purpose of this paper is to describe a few of the suggested advanced concepts for fast breeder reactors and to compare these with the standard approach as to their potential advantage. I have attempted to estimate the economic effect of full technical success with each of the proposed concepts. The proposed concepts include: (1) single sodium system, (2) steam-cooled core concept, (3) direct cycle reactor using potassium as reactor coolant and working fluid, (4) molten plutonium-fuel alloy circulated and cooled by a jet of sodium, (5) settled-bed core, (6) molten salt concept, and (7) paste-fuel system.
Date: November 11, 1963
Creator: Hammond, R. Philip
open access

Analysis of UO2 Grain Growth Data From "Out of Pile" Experiments

Description: Summary: Data on equlaxed UO2 grain growth from "out of pile" experiments have been gathered from all known sources and analyzed to determine the relationship between the grain size developed and annealing temperature and between grain size and the time at temperature. On the basis of the analysis, an equation relating gain size to time and temperate has been selected that appears to best describe the data considered as a whole. The coefficients in this grain growth equation have been evaluated to indicate the variance between different investigations and/or different UO2 sinters. The general applicability and limitations of "out of pile" grain growth data for the determination of temperatures in the microstructures of irradiated UO2 are discussed. Specific recommendations are made for the conditions under which grain size can be reliably employed as a temperature indicator. The objective in undertaking this analysis on UO2 grain growth was to obtain a working relationship between UO2 grain size and annealing time and/or temperature, and also a measure of the potential variation in the relationship. The intended use of the results was the determination of temperatures based on the grain sized observed in the post-irradiation metallographic examination of AEC-Euratom High Performance UO2 Program fuel capsules. The results are being reported in the belief that they will be of use in the analysis of other fuel experiments.
Date: November 1963
Creator: Lyons, M. F.; Coplin, D. H. & Weidenbaum, B.
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Application of the Variational Method to the Calculation of the Time Dependence of the Neutron Flux in Small Pulsed Slabs, Cylinders and Spheres

Description: The variational method is applied to the monoenergetic time dependent transport equation to obtain a simple relation for the asymptotic decay constant in small pulsed assemblies. The results indicate that flat trial functions may be a reasonable representation of the flux distributions in the thin slab limit. This approach is superior to many of the usual transport approximations.
Date: December 16, 1963
Creator: Judge, F. D. & Daitch, Paul B. (Paul Bernard), 1925-
open access

Applications of Strain Cycling Considerations to Superheat Fuel Design

Description: 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.
Date: June 1963
Creator: Rieger, G. F.
open access

Approximate Models for Distributed-Parameter Heat-Transfer Systems

Description: Summary: The use of dimensionless-parameter frequency response diagrams to determine accuracies of lumped-parameter approximations is demonstrated by two examples: calculation of the heat flux at the surface of a semi-infinite solid due to temperature fluctuations of an adjacent fluid; and the response of a counterflow heat exchanger to inlet fluid temperature perturbations. Dimensionless system parameters make it possible to use general-purpose plots to find the error in particular approximations as a function of the frequency of perturbation. Such plots are directly applicable to control-system stability problems, where the highest frequency of interest is usually apparent.
Date: August 20, 1963
Creator: Ball, S. J.
open access

Asymptotic Neutron Spectra in Multiplying Media

Description: Asymptotic low energy neutron spectra have been measured for two multiplying systems. The reentrant hold spectrum (scalar flux) and the surface leakage spectrum were obtained for both assemblies using the pulsed-source chopper technique at the RPI linear accelerator.
Date: November 1963
Creator: Slovacek, R. E.; Fullwood, R. R.; Gaerttner, Erwin Rudolf, 1911- & Bach, D. R.
open access

Automatic Exit Steam Quality Control for Boiling Water Reactors

Description: From American Nuclear Society Meeting, New York, Nov. 1963. The need for control of the flow distribution and/or steam quality in boiling reactors is discussed. A quality control device is being developed which consists of an entrance venturi and an exit venturi for measuring the flow rates into and out of the channel, means for comparing the two flow rate signals, and a value for regulating the flow rate. This device can be used either as a constant quality device or as a controlled-quality device. Results are given of air-water studies of two-phase flow in a vertical venturi.
Date: November 1963
Creator: Gall, D. A. & Doyle, E. F.
open access

Behavior of Irradiated Metallic Fuel Elements Exposed to Nuclear Excursion in TREAT

Description: In fast reactor safety studies, it is imperative to know the effects of temperature excursions on the fuel elements. Previous controlled out-of-pile experiments on the behavior of uranium fuel elements under meltdown or near-meltdown conditions have been performed using direct electrical resistance heating or furnace heating. As a step toward obtaining more complete information on reactivity effects accompanying fuel meltdown, the behavior of irradiated EBR II and Fermi A samples under transient nuclear heating in TREAT has been studied. The experiment results obtained indicate that effects of prior irradiation can produce significant effects upon reactivity changes produced by meltdown of metallic fast reactor fuel pins.
Date: November 1963
Creator: Monaweck, J. H.; Dickerman, Charles Edward, 1932- & Sowa, E. S.
open access

Beta Radiation Processing at Rigorous Conditions

Description: Introduction: The literature reflects ever expansive studies of radiation chemistry over the past twenty years However, in the application of radiation processing to chemical reactions, in general and excepting a few isolated cases, the yield of useful products have been so low as to preclude practical utilization. Thus, for many reactions,radiation alone at ambient conditions is not a sufficient agent for economical production. Hence, we are led to the investigation of radiation effects on reactions at elevated temperatures and pressures where the thermodynamics favor more extensive reactions that may be induced by radiation. the probability of developing a successful practical radiation process is increased when applying radiation at rigorous conditions. To have a commercial advantage, a radiation process usually must replace an expensive catalyst system, generate a reaction at somewhat less rigorous conditions than is usually employed or yield a better or unique product of high value. In our investigations, we have examined only the potential of radiation as a replacement for contact catalyst. Results: We have worked with coal extract rather than coal because it can be melted or dissolved to facilitate pumping into the processing unit and, in general, permits easier handling than a solid. From numerous radiation runs with coat extract in the liquid phase, treated with 5000 psi of hydrogen pressure, temperatures up to 430 degree C, and total dose of up to 6 megarand, we have disappointingly but conclusively observed red that radiation does not induce hydrogenation beyond that obtain by thermal reaction alone.
Date: November 15, 1963
Creator: Yavorsky, P. M. & Gorin, E.
open access

Boiling Studies for Sodium Reactor Safety: Part 1, Experimental Apparatus and Results of Initial Tests and Analysis

Description: Abstract: An experimental and analytical research program is described which is designed to meet certain specific needs for data and methods required to make improved predictions of transient voids, burnout, flow, and fuel temperature during extreme accidents in sodium-cooled reactors.
Date: August 30, 1963
Creator: Noyes, R. C.
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