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Development of Fueled Graphite Containing Pyrolytic-Carbon Coated Carbide Particles for Nonpurged, Gas-Cooled Reactor Systems

Description: Abstract: Progress is reported in several areas of development of fueled graphite containing coated particles for nonurged gas-cooled reactor systems. The sol-gel process has been modified for making spherical particles of both thorium-uranium carbide and thorium-uranium oxide suitable for coating. Equipment has been assembled and methods have been developed for deposition of pyrolytic-carbon coating under well-controlled conditions. Damage to coated particles during fabrication into a graphite matrix depends on the molding pressure and the volumetric content of coated particles. Vendor-supplied coated particles and fueled graphite spheres have been evaluated extensively in both in- and out-of-reactor tests. Duplex- and triplex-coasted particles have excellent fission-gas retention at 2050 degree F to burnups of 15 at. % burnup. Fueled graphite spheres containing coated particles have good irradiation performance, but the fission-gas release rates are somewhat higher than for unsupported coated particles. Fueled graphite spheres react with water vapor about as rapidly as do Speer Mod-2 and ATJ grades of graphite. The diffusion rates in pyrolytic carbon are the same for uranium, thorium, and protactinium. The diffusion rates in the direction parallel to the deposition plane are much higher than those in the perpendicular direction.
Date: November 1963
Creator: Carlsen, F. L., Jr.; Bomar, E. S. & Harms, W. O.
Partner: UNT Libraries Government Documents Department
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Reactivity Worth of Transverse Gaps

Description: Technical report discussing a series a experiments on the reactivity worth of gaps has been performed in the KAPL Solid Homogeneous Assembly (SHA). One objective of the program is to provide data against which calculated models can be checked. An immediate goal is to develop a method by which large void regions can be adequately treated within the framework of diffusion theory. This would enable the nuclear engineer to perform standard design calculations on systems containing such voids. Another objective of the program is to provide data which will allow the shutdown margin of split bed assemblies to be more adequately estimated. for this latter purpose not only the reactivity work of gaps is required by also the rate of change of reactivity with distance as a function of gap size.
Date: November 1963
Creator: Weinstein, S. & Feiner, Frank
Partner: UNT Libraries Government Documents Department
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Recent Developments in the Physics and Safety of Large Fast Power Reactors

Description: Technical report discussing three principal areas: (1) some recent cross section measurements and their effect on fast reactor calculations; (2) the question of Doppler and sodium void reactivity effects in large fast power reactors and the conflicts inherent in simultaneous optimization of performance, breeding, and safety characteristics; (3) the matter of hybrid fuel cycles.
Date: November 1963
Creator: Okrent, David
Partner: UNT Libraries Government Documents Department
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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.
Partner: UNT Libraries Government Documents Department
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Development and Evaluation of Large Volume Scintillation Detectors and Their Application to Radioisotope Process Control

Description: Preliminary phases of this investigation that have been completed include basic studies to determine optimum detector engineering characteristics and static tests of a number of designs. A pilot system for dynamic testing of the detectors in simulated process control applications is presently in operation.
Date: November 1963
Creator: Perry, J. Kent
Partner: UNT Libraries Government Documents Department
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Buckling Measurements : Heavy Natural Uranium Tubular Fuel Assemblies

Description: One-region buckling measurements that were made on a series of D/sub 2/O- moderated lattices of heavy uranium metal tubes in the Process Development Pile at Savannah River Laboratory are presented. The purposes of these measurements are to provide normalization points for lattice bucklings and to extend the study of natural uranium- D/sub 2/O systems. The dependence of buckiing on the moderator-to-fuel ratio is studied for two types of lattices.
Date: November 20, 1963
Creator: Dunklee, A. E. & Graves, William E. (William Ernest), 1941-
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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The Diffusion of Fast Neutrons

Description: From American Nuclear Society Meeting, New York, Nov. 1963. The use of the asymptotic solution to the one-velocity transport equation is considered. The angular distribution for fast neutron elastic scattering by heavy elements is discussed. An exponential angular distribution on is assumed to simplify the decay length calculation. The diffusion length of 1 to 15 Mev neutrons in iron is calculated, as well as the vector flux angular dependence. The asymptotic solution for an arbitrary angular distribution of a plane delta -function source is also found. An isotropic source is investigated, and some applications of the model are examined.
Date: November 1963
Creator: Francis, N. C.; Brooks, E. J. & Watson, R. A.
Partner: UNT Libraries Government Documents Department
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Energy Deposition by Fast Neutrons. [Part] II, Yield of the Fricke Dosimeter at 14.6 Mev

Description: A measurement of the yield of the aerated, ferrous sulfate-sulfuric acid (Fricke) dosimeter for 14.6-Mev neutrons gave a value of GF /sub Fe/sup +5/= 11.5 plus or minus 1.8. G/sub Fe/ number of ferric ions produced per 100 ev deposited. The determination combined an analysis of the energy deposit by scattering and charged particle reactions with a determination of the neutron flux by two independent means: (1) a "long counter" method and (2) an activation technique. The result is in reasonable agreement with a prediction for G/sub Fe// sup plus or minus 5/ based on measured yields of the dosimeter to irradiations by monoenergetic charged particles.
Date: November 1963
Creator: Axtmann, Robert C. & Licari, Joseph A.
Partner: UNT Libraries Government Documents Department
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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.
Partner: UNT Libraries Government Documents Department
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Nuclear Analysis of PM Long Life Core 3

Description: Introduction. Under AEC contract the Martin Company has followed up the design and construction of the PM-1 and PM-3A nuclear power plants with R&D efforts seeking improved plant efficiency, increased core life and higher operating power. The Advanced PM cores have evolved step by step, with the addition of degrees of freedom to design latitude. A first replacement core, Core 2, has been designed to achieve 50 percent greater life than PM-1 through relatively minor design changes. Core 3 realizes the potential extensive modifications in the fuel element and control element configurations. This paper outlines an analysis effort undertaken to define what may be called a performance profile over a range of configurations of interest for Core 3. It should be emphasized that this is a parametric or concept study and not a final design effort. The results of this study clearly indicate that a lifetime of 100 Mw-yr can be obtained from a 7 ft pressurized water core. If employed as a 10-Mw heat source for present PM equipment, this core has a lifetime approaching that of the plant equipment, 90,000 full-power hours. Core 3 will be suitable for applications demanding up to 40-Mw operating thermal power.
Date: November 1963
Creator: Bagley, Raymond. & George, Critz.
Partner: UNT Libraries Government Documents Department
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Feasibility of a Liquid Phase Chemonuclear Ozone Process

Description: At the Chemonuclear Workshop held at Brookhaven National laboratory in November 1962 it was pointed out that the production of ozone from oxygen by a liquid phase fission fragment chemonuclear process appears to have reasonable economic potential. The maximum theoretical reaction yield for the formation of ozone from oxygen is a "G" value of 68 molecules for 100 ev based on heat of reaction data. The authors felt a "G" value of 15 to be reasonable for this study. the reactor system chosen has liquid oxygen as its moderator and the operating pressure and temperature were selected so as to allow boiling of the oxygen-ozone mixture. The total plant investment cost is estimated to be in the range of $100,000,000. Other system designs will be considered in the future.
Date: November 19, 1963
Creator: Cagnetta, J. P.; Goellner, D. & Steinberg, M.
Partner: UNT Libraries Government Documents Department
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Fluxes and Reaction Rates in the Presence of Interferring Resonances

Description: The effects of competition between resonances of different isotopes were investigated. Flux and reaction rate calculations on a Pu/sup 239/-- U/sup 238/ system revealed that U/sup 238/ exhibits both self-shielding and interference effects, the latter becoming noticeable at enrichment of a few per cent. Gold activation was also found to be depressed by the presence of U, but was insensitive at low enrichment values, Investigation of the Pu/sup 239/ resonance integral showed an asymmetric effect involving both interference between potential and resonant scattering and interference with resonance absorption in another isotope. The interference scattering arising in each resonance level had a notable effect on the average change in the Doppler coefficient. (D.C.W.)
Date: November 1963
Creator: Kelber, Charles N.
Partner: UNT Libraries Government Documents Department
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Effect of Eddy Diffusion on Temperatures in a Fixed Bed, Particulate-Fueled Nuclear Reactor

Description: Abstract: To assess diffusion's importance, the temperature distribution in a cylindrical reactor is derived for a coolant with uniform properties and velocity, taking into account both radial and axial diffusion, for a cosine-J0 power distribution. The fractional temperature rise of the coolant is found to be [chemical formula] where E(z) = [sin(z) + sin(Z)]/2 sin(Z), z= π x/2′, x is the axial distance from the core center, -H and ′ are the core half-height and extrapolated half-height, -H≤x≤H; Fn = 1/J0(Pn)·[(Pn/2.405P)2-10, J1(Pn) = 0, P= R/R′ = core radius/extrapolated radius, ρ = r/R, r = radial distance from axis, 0≤r≤R; an = = βnH/Z, 2 Aβn + 1 =[1 + 4αβ(Pn/R)2]½, A = axial diffusivity /u, B = radial diffusivity /u, u = coolant axial velocity, and [chemical formula]. The expression is evaluated for a variety of values for all the parameters, and the results are discussed analytically and presented in tables and graphs. The effect is dependent upon the relative size of the diffusion eddies in comparison with the dimensions of the reactor. The eddy diffusivity is proportional to the size of the particles in the bed and is about ten times larger axially than radially. A small core with large fuel particles will be affected by eddy diffusion, thereby reducing hot spots, but a large core with small particles will not. For a core 8 ft in diameter cooled by sodium flowing at 2 ft/sec, the effect is perceptible with 2-in. particles, but not with 0.2-in. particles.
Date: November 1963
Creator: Barker, James J. & Benenati, Robert F.
Partner: UNT Libraries Government Documents Department
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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.
Partner: UNT Libraries Government Documents Department
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Effect of Radiation on Mechanical Properties of CVTR Pressure Tube Material

Description: An essential part of establishing the acceptability of warm extruded Zircaloy-4 for the CVTR pressure tube application was the determination of irradiation effects on mechanical properties of the alloy. Representative specimens were irradiated in low temperature process water in the WTR for simulated two, three and five year exposure. The effects of this irradiation were then evaluated in terms of changes in tensile, impact and creep properties. The experiment results concluded that the irradiation-induced changes in mechanical proprieties will not introduce any operational hazard to the CVTR pressure tube under anticipated operating conditions.
Date: November 1963
Creator: Smalley, W. R.
Partner: UNT Libraries Government Documents Department
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The Determination of k∞ From Measurements on a Small Test Sample in a Critical Assembly

Description: Abstract. The determination of the infinite multiplication factor, k∞ , from measurement son a small test sample was investigated by both theoretical and experimental techniques. Theoretical relations were developed to calculate the error in the measurement due to a mismatch between the flux ratios in the critical assembly and those of the test sample. Experiments were carried out at the Hanford Laboratory of the General Electric Company with the PCTR, to obtain values of the multiplication factor for comparison with the theoretical results. Calculations with two-group theory gave results that agreed with the experimental results when the test sample, with natural uranium fuel, was surrounded by a buffer region of the same material. When this buffer region was loaded with highly enriched fuel, the errors in the measured values were not predicted by the two-group theory. Three-group theory relations were derived which gave calculated values in agreement with the experimental values and indicated that a mismatch of the epithermal neutron group leads to the measured differences in the value of k∞ for the two buffer types.
Date: November 1963
Creator: Lanning, David Dayton
Partner: UNT Libraries Government Documents Department
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Sodium Separation From Biological Material

Description: This study is part of a research into trace element physiology of fresh water snails. As an average, biological materials contain [approximately] o.0% (fresh weight) NaCl ; this means [approximately] 3540 mg Na/1 (in snails, 0.4% NaCl [approximately] ms/1). Under these conditions, the application of neutron activation plus gamma spectrum analysis for the study of most trace elements as a routine method, is difficult. We will narrow down the scope some more and consider only the interference between Na24 and Cu64.
Date: November 1963
Creator: Spronk, N.
Partner: UNT Libraries Government Documents Department
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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.
Partner: UNT Libraries Government Documents Department
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Effect of Fluoride Ions on the Aqueous Corrosion of Zirconium Alloys

Description: Abstract. A review has been made of the effects of fluoride ions on the corrosion behavior of zirconium alloys in high-temperature water. Corrosion was found to occur as the result of contamination of the water or the zirconium surface. A major source of fluorides is undue delay in rinsing the HF-HNO3 pickling solution during surface preparation. The oxide on corrosion-resistant material has been found to contain up to 7600 ppm fluoride from this source. The threshold concentration of fluoride in the oxide film which produces poor corrosion resistance ranges from 8500 to 17,000 ppm. Accelerated corrosion from fluorides in water at 300 to 360 C occurs at about 100 ppm, although increased corrosion has been reported at 10 ppm fluoride in water at 300 C. Fluorocarbon plastics degrade and contribute fluorides to the high-temperature water or to the alloy surface when in direct contact with zirconium. Chlorides (1 to 10,000 ppm) and iodides (1270 ppm) do not adversely affect the corrosion behavior of zirconium alloys in water at 360 C. The mechanism of corrosion is not well understood but apparently is related to the formation of insoluble zirconium oxyfluorides during pickling and during exposure to fluoride-contaminated water.
Date: November 1963
Creator: Berry, Warren E., 1922-
Partner: UNT Libraries Government Documents Department
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A High Speed Readout for Multi-Channel Pulse Height Analyzers

Description: From American Nuclear Society Meeting, New York, Nov. 1963. In computer-coupled automated activation analysis such as in the Mark II system, conventional methods of data readout impose a serious restriction on the minimum handling time per sample. A data coupler for operating between the data accumulation system and the computer tape unit was developed which contributes nothing to the handling time per sample, does not distort the data, and prepares the data for direct computer entry. In addition to activation analysis, the coupler may be used to obtain successive spectra separated in time by 0.16 sec in the study of short-lived isotopes.
Date: November 1963
Creator: Wilkins, W. W.; Fite, L. E. & Wainerdi, Richard E., 1931-
Partner: UNT Libraries Government Documents Department
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Statistical Techniques Used in the Specific Zirconium Alloy Design Program

Description: Technical report describing the statistically designed empirical approach being used to choose a candidate Zr alloy optimum with respect to corrosion and hydriding rates in steam and having acceptable mechanical properties. The statistical techniques used and the reasons for their use are discussed in detail, with emphasis on the estimation of corrosion rates. Estimation of response surfaces is also considered.
Date: November 11, 1963
Creator: Jaech, John L.
Partner: UNT Libraries Government Documents Department
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Maritime Loop Irradiation Program for Savannah I Fuel Post-Irradiation Examination of SI5BM Fuel Assembly

Description: Abstract: A stainless steel clad 9-rod assembly fabricated by The Babcock & Wilcox Company was irradiated in a boiling water loop of the General Electric Test Reactor. A post-irradiation examination revealed no significant dimensional changes on the fuel rods. the results of mass spectrometric analysis made of the pelletized UO2 fuel indicated a maximum burnup of 11,500 MWD/tonne was attained by Rod B-4 during the exposure.An x-ray diffraction examination of an unirradiated fuel sample revealed the presence of UN2 and U2N3 phases. Metallographic examination of the irradiated microstructures revealed similar second-phase particles.
Date: November 7, 1963
Creator: Mathay, P. W.
Partner: UNT Libraries Government Documents Department
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