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Consequence model of the German reactor safety study

Description: The consequency model developed for phase A of the German Reactor Safety Study (RSS) is similar in many respects to its counterpart in WASH-1400. As in that previous study, the model describes the atmosphere dispersion and transport of radioactive material released from the containment during a postulated reactor accident, and predicts its interaction with and influence on man. Differences do exist between the two models however, for the following reasons: (1) to more adequately reflect central European conditions, (2) to include improved submodels, and (3) to apply additional data and knowledge that have become available since publication of WASH-1400. The consequence model as used in phase A of the German RSS is described, highlighting differences between it and the U.S. model.
Date: January 1, 1979
Creator: Bayer, A.; Aldrich, D.; Burkart, K.; Horsch, F.; Hubschmann, W.; Schueckler, M. et al.
Partner: UNT Libraries Government Documents Department

Dy163-Ho163 branching: an s-process barometer

Description: The neutron capture cross sections of Dy163 and Er164 have been measured to analyze the s-process branching at Dy163-Ho163. The reproduction of the s-process abundance of Er164 via this branching is sensitive to temperature kT, neutron density, and electron density n/sub e/. The calculations using information from other branchings on kT and the neutron density n/sub n/ give constraints for n/sub e/ at the site of the s-process.
Date: January 1, 1984
Creator: Beer, H.; Walter, G. & Macklin, R.L.
Partner: UNT Libraries Government Documents Department

LWR source terms for loss-of-coolant and core melt accidents

Description: Fission product source terms for loss-of-coolant and core meltdown accidents in light water reactors are reviewed. The results presented in the Reactor Safety Study are summarized, and modifications of these results, due to more recent experimental studies, are described.
Date: January 1, 1980
Creator: Malinauskas, A.P.; Lorenz, R.A.; Albrecht, H. & Wild, H.
Partner: UNT Libraries Government Documents Department

Fuel-coolant interaction-phenomena under prompt burst conditions. [LMFBR]

Description: The Prompt Burst Energetics (PBE) experiments conducted at Sandia Laboratories are a series of in-pile tests with fresh uranium oxide or uranium carbide fuel pins in stagnant sodium. Fuel-coolant-interactions in PBE-9S (oxide/sodium system) and PBE-SG2 (carbide/sodium) have been analyzed with the MURTI parametric FCI code. The purpose is to gain insight into possible FCI scenarios in the experiments and sensitivity of results to input parameters. Results are in approximate agreement for the second (triggered) event in PBE-9S (32 MPa peak) and the initial interaction in PBE-SG2 (190 MPa peak).
Date: January 1, 1979
Creator: Jacobs, H.; Young, M.F. & Reil, K.O.
Partner: UNT Libraries Government Documents Department

Release of fission products during controlled loss-of-coolant accidents and hypothetical core meltdown accidents. [PWR; BWR]

Description: A few years ago the Projekt Nukleare Sicherheit joined the United States Nuclear Regulatory Commission in the development of a research program which was designed to investigate fission product release from light water reactor fuel under conditions ranging from spent fuel shipping cask accidents to core meltdown accidents. Three laboratories have been involved in this cooperative effort. At Argonne National Laboratory (ANL), the research effort has focused on noble gas fission product release, whereas at Oak Ridge National Laboratory (ORNL) and at Kernforschungszentrum Karlsruhe (KfK), the studies have emphasized the release of species other than the noble gases. In addition, the ORNL program has been directed toward the development of fission product source terms applicable to analyses of spent fuel shipping cask accidents and controlled loss-of-coolant accidents, and the KfK program has been aimed at providing similar source terms which are characteristic of core meltdown accidents. The ORNL results are presented for fission product release from defected fuel rods into a steam atmosphere over the temperature range 500 to 1200/sup 0/C, and the KfK results for release during core meltdown sequences.
Date: January 1, 1978
Creator: Albrecht, H. & Malinauskas, A.P.
Partner: UNT Libraries Government Documents Department

HDR (Heissdampfreaktor) Phase 2 vibrational experiments

Description: As part of the second phase of vibrational/earthquake investigations at the HDR (Heissdampfreaktor) Test Facility in Kahl/Main, FRG, high-level shaker tests (SHAG) were performed during June and July 1986. The purpose of these experiments is to investigate full-scale structural response, soil-structure interaction, and piping and equipment response under strong excitation conditions. While global safety considerations imposed load limitations, the HDR soil/structure system was nevertheless tested to its capacity limits. The performance of up to seven different multiple support pipe hanger configurations (ranging from flexible to stiff systems) was evaluated in the tests. Data obtained in the tests serve to validate analysis methods.
Date: October 1, 1986
Creator: Malcher, L. & Kot, C.A.
Partner: UNT Libraries Government Documents Department

Use of (D, MUF) and maximum-likelihood methods for detecting falsification and diversion in data-verification problems

Description: The investigation of data falsification and/or diversion is of major concern in nuclear materials accounting procedures used in international safeguards. In this paper, two procedures, denoted by (D,MUF) and LR (Likelihood Ratio), are discussed and compared when testing the hypothesis that neither diversion nor falsification has taken place versus the one-sided alternative that at least one of these parameters is positive. Critical regions and detection probabilities are given for both tests. It is shown that the LR method outperforms (D,MUF) when diversion and falsification take place.
Date: January 1, 1982
Creator: Goldman, A.S. & Beedgen, R.
Partner: UNT Libraries Government Documents Department

Calibration of a drag disc turbine transducer and a gamma beam densitometer to measure the mass flow rate in separated horizontal two-phase flow

Description: The accurate measurement of two-phase mass flow rate is very important in experiments, such as the LOFT experiment, which investigate the hypothetical Loss-of-Coolant Accident (LOCA). This paper analyzes experiments designed to determine the behavior of a LOFT free field drag disc turbine transducer (DTT) and a LOFT-type three-beam gamma densitometer in a steady state, horizontal high pressure steam-water flow. The experiments were conducted in a mass flow and void fraction range where a variety of separated flow regimes existed which strongly influenced the performance of the DTT. It is shown that the accuracy of the instruments is mainly a function of the void fraction.
Date: January 1, 1979
Creator: Reimann, J. & Solbrig, C.W.
Partner: UNT Libraries Government Documents Department

Dynamic analyses of a crack run-arrest experiment in a nonisothermal plate

Description: In crack-arrest studies sponsored by the Heavy-Section Steel Technology (HSST) Program, a primary objective has been to produce fracture toughness data for reactor pressure vessel materials at temperatures approaching the Charpy upper-shelf regime. Wide-plate tests being conducted at the National Bureau of Standards for the HSST Program are providing an opportunity to obtain significant numbers of data points at affordable costs. In these tests, a single-edge crack in a wide-plate which is subjected to tensile loading initiates at low temperature and arrests in a region of increased fracture toughness. The gradient in toughness is achieved by applying a linear transverse temperature profile across the plate. The second test in this series for A 533 grade B class 1 steel involves crack initiation in cleavage followed by arrest at a temperature corresponding to Charpy upper-shelf behavior. The plate geometry, the material properties, and the instrumentation are discussed along with conditions and results for this test. Pretest static and elastodynamic analyses are described, and posttest analyses based on actual boundary conditions are shown to compare favorably with the observed run-arrest events.
Date: June 1, 1985
Creator: Bass, B.R.; Pugh, C.E. & Stamm, H.K.
Partner: UNT Libraries Government Documents Department

Present and future aspects of PROSA: A computer program for near real time accountancy

Description: The methods of near real time accountancy (NRTA) for safeguarding nuclear material received a lot of attention in the last years. We developed PROSA 1.0 as a computer program to evaluate a sequence of material balance data based on three statistical tests for a selected false alarm probability. A new NRTA test procedure will be included and an option for the calculation of detection probabilities of hypothetical loss patterns will be made available in future releases of PROSA. Under a non-loss assumption, PROSA may also be used for the analysis of facility measurement models.
Date: July 1, 1987
Creator: Beedgen, R.
Partner: UNT Libraries Government Documents Department

Neutron capture cross sections of /sup 178/,/sup 179/,/sup 180/Hf and the origin of nature's rarest stable isotope /sup 180/Ta

Description: The neutron capture cross sections of /sup 178/,/sup 179/,/sup 180/Hf were measured in the energy range 2.6 keV to 2 MeV. The average capture cross sections were derived and fitted in terms of strength functions. Resonance parameters for the observed resonances below 10 keV were determined by shape analysis. Maxwellian-averaged capture cross sections were computed for thermal energies with kT between 5 and 100 keV. The cross sections for kT = 30 keV were used to determine the population probability of the 8- isomeric level in /sup 180/Hf by neutron capture as (1.24 +- 0.06)% and the r-process abundance of /sup 180/Hf as 0.0290 (Si = 10/sup 6/). These quantities served to analyze s- and r-process nucleosynthesis of /sup 180/Ta, nature's rarest stable isotope.
Date: January 1, 1982
Creator: Beer, H. & Macklin, R.L.
Partner: UNT Libraries Government Documents Department

The LISA-1 and TRIO in-pile tests

Description: The in-pile tests TRIO and LISA-1 involve measurement of in-situ tritium release as a function of time, temperature and sweep gas conditions. These in-situ tritium recovery experiments are similar in concept to other in-pile tests such as the VOM series, Exotic, and the LILA series. TRIO used a single capsule with lithium aluminate. The results from TRIO have been compiled, evaluated and reported. The LISA-1 experiment had six test capsules: one lithium aluminate, one lithium orthosilicate (Li/sub 4/SiO/sub 4/), and four lithium metasilicate (Li/sub 2/SiO/sub 3/). A previous report gives a description of the experimental setup, experimental observations, and preliminary results. Presented herein is a more detailed evaluation of the LISA-1 experimental results for the three breeder materials. The results from LISA are then compared to those of TRIO.
Date: October 27, 1986
Creator: Clemmer, R.G.; Werle, H. & Briec, M.
Partner: UNT Libraries Government Documents Department

Modeling the cooldown of force-cooled coils

Description: This paper describes a finite difference computer program which simulates the cooldown of force-cooled superconducting coils. The basic theory is discussed and the method of calculation used in the program is described. Some of the problems associated with computer modeling of a cooldown are discussed. The program capability is demonstrated on a three-dimensional model which represents the 1000 kg cryogenic model of the Euratom LCT coil. From computer simulation using the program described here, a method for cooling down large forced cooled superconducting coils can be developed.
Date: March 1, 1981
Creator: Green, M.A.; Mitina, S. & Krafft, G.
Partner: UNT Libraries Government Documents Department

Measurements of electromagnetic properties of LCT (Large Coil Task) coils in IFSMTF (International Fusion Superconducting Magnet Test Facility)

Description: Participants in the international Large Coil Task (LCT) have designed, built, and tested six different toroidal field coils. Each coil has a 2.5- by 3.5-m, D-shaped bore and a current between 10 and 18 kA and is designed to demonstrate stable operation at 8 T, with a superimposed averaged pulsed field of 0.14 T in 1.0 s and simulated nuclear heating. Testing of the full six-coil toroidal array began early in 1986 and was successfully completed on September 3, 1987, in the International Fusion Superconducting Magnet Test Facility (IFSMTF) at Oak Ridge National Laboratory (ORNL). This paper summarizes electromagnetic properties of LCT coils measured in different modes of energization and fast dump. Effects of mutual coupling and induced eddy currents are analyzed and discussed. Measurements of the ac loss caused by the superimposed pulsed fields are summarized. Finally, the interpretation of the test results and their relevance to practical fusion are presented. 11 refs., 10 figs., 4 tab.
Date: January 1, 1987
Creator: Shen, S.S.; Baylor, L.R.; Dresner, L.; Fehling, D.T.; Lubell, M.S.; Lue, J.W. et al.
Partner: UNT Libraries Government Documents Department

A confirmatory measurement technique for HEU (highly enriched uranium)

Description: Precise measurements of the special nuclear material (SNM) in an item can be used to confirm that the item has not been tampered with. These measurements do not require a highly accurate calibration, but they should be based on an attribute that is unique to the SNM. We describe an instrument that performs gamma-ray measurements at three energies: 185.7 keV, 1001 keV, and 2614 keV. This instrument collects data for 200 s from shipping containers (208-l barrels). These measurements help to distinguish the issue of material control - Has any material been diverted. - from the issue of measurement control - Is there a measurement bias.
Date: January 1, 1987
Creator: Sprinkle, J.K. Jr.; Goldman, A.; Russo, P.A.; Stovall, L.; Brumfield, T.L.; Gunn, C.S. et al.
Partner: UNT Libraries Government Documents Department

Ceramic breeder materials

Description: Ceramic materials are under investigation as potential breeder material in fusion reactors. This paper will review candidate materials with respect to fabrication routes and characterization, properties in as-fabricated and irradiated condition, and experimental results from laboratory and inpile investigations on tritium transport and release. Also discussed are the resources of beryllium, which is being considered as a neutron multiplier. The comparison of ceramic properties that is attempted here aims at the identification of the most-promising material for use in a tritium breeding blanket. 82 refs., 12 figs., 5 tabs.
Date: January 1, 1987
Creator: Johnson, C.E.; Kummerer, K.R. & Roth, E.
Partner: UNT Libraries Government Documents Department

MHD (magnetohydrodynamic) flow tailoring in first wall coolant channels of self-cooled blankets

Description: MHD flow tailoring, the use of salient features of MHD flows in strong magnetic fields to create desirable velocity profiles in single ducts, presents the possibility of significant reduction in blanket complexity and cost, and enhancement of thermal hydraulic performance. A particular form of flow tailoring, involving ducts with alternating expansions and contractions lends itself to the design of first wall coolant ducts. The potential benefits of this configuration and its immediate applicability to blanket design have made it the choice as the first joint Argonne National Laboratory (ANL)/Kernforschungszentrum Karlsruhe (KfK) test on liquid metal MHD. Testing is being carried out at ANL's ALEX facility on a test article fabricated at KfK. A description of the test article, its important features, and the associated instrumentation are presented. A fully 3-D code capable of treating MHD flows in ducts of complex geometry has been developed and used in the flow tailoring experiements. The features and capabilities of the code are discussed and a sample of the code predictions for the geometry and conditions of the experiments are presented. A sample of the preliminary test results from the ongoing testing is also given. 9 refs., 9 figs.
Date: February 1, 1988
Creator: Picologlou, B.F.; Reed, C.R.; Hua, T.Q.; Barleon, L.; Kreuzinger, H. & Walker, J.S.
Partner: UNT Libraries Government Documents Department

The IEA large coil task test results in IFSMTF

Description: The Large Coil Task (LCT) is an international collaboration of the United States, EURATOM, Japan, and Switzerland to develop large superconducting magnets for fusion reactors. The testing phase of LCT was completed on September 3, 1987. All six coils exceeded the design goals, both as single coils and in six-coil toroidal tests. In addition, a symmetric torus test was performed in which a maximum field of 9 T was reached in all coils simultaneously. These are by far the largest magnets (either in size, weight, or stored energy) ever to achieve such a field. 6 refs., 6 figs., 3 tabs.
Date: January 1, 1987
Creator: Lubell, M.S.; Clinard, J.A.; Dresner, L.; Fietz, W.A.; Fletcher, W.M.; Haubenreich, P.N. et al.
Partner: UNT Libraries Government Documents Department

Measurement of. pi. /sup -/p. -->. pi. /sup 0/. pi. /sup 0/n at 6, 8 and 12 GeV/c*. [Angular distributions, S-wave enhancement]

Description: All ..gamma..'s and the neutron of this reaction are detected. From the experimental angular distributions the magnitude of the ..pi../sup 0/..pi../sup 0/ S-wave is determined for the ..pi pi.. mass range 600 to 1400 MeV and the cosinus of its phase angle (relatively to the known D-wave) is given for the range 1000 to 1400 MeV. The I = O amplitude S/sub 0/ is near the unitarity limit in the range 600 to 900 MeV and again around 1200 MeV. The data support the known facts of a very broad S-wave enhancement on which is superimposed a large inelasticity due to the KK-threshold effect.
Date: January 1, 1978
Creator: Apel, W D; Auslander, J S & Muller, H
Partner: UNT Libraries Government Documents Department

Vibrational experiments at the HDR (Heissdampfreaktor) German/US cooperation

Description: As part of an overall effort on the validation of seismic calculational methods, the US NRC/RES is collaborating with the Kernforschungszentrum Karlsruhe, FRG, in the vibrational/earthquake experiments conducted at the HDR (Heissdampfreaktor) Test Facility in Kahl/Main, FRG. In the most recent experiments (SHAG), high level excitations were produced in the HDR by means of an eccentric-mass coastdown shaker capable of developing 1000 tons of force. The purpose of the experiments was to investigate full-scale structural response, soil-structure interaction, and piping and equipment response. Data obtained in the tests serve to evaluate analysis methods. In the SHAG experiments, loadings of the HDR soil-structure system approached incipient failure levels as evidenced by high peak accelerations and displacements, local damage, nonlinear behavior, soil subsidence, and wall strains which exceeded estimated limit values. Also, the performance of different pipe hanger configurations for the VKL piping system was compared in these tests under high excitation levels. The support configurations ranged from very rigid systems (strut/snubbers) to very flexible configurations (spring and constant force supports). Pretest and post-test analyses for the building/soil and piping response were performed and are being validated with the test data.
Date: April 1, 1987
Creator: Kot, C.A.; Malcher, L. & Costello, J.F.
Partner: UNT Libraries Government Documents Department

Effect of composition and radiation on the Hertzian indentation behavior of nuclear waste glasses. [77-MeV alpha particles]

Description: The Hertzian indentation technique has been used to determine the fracture toughness, K/sub Ic/ of two borosilicate glasses developed to contain high-level nuclear waste. For the product VG 98/12, adding selected groups of fission products leaves K/sub Ic/ unchanged, but addition of Pb lowers K/sub Ic/ by approx. 20%. Radiation with 77 MeV ..cap alpha..-particles to a dose of approx. 10/sup 15/ ..cap alpha../cm/sup 2/ increases K/sub Ic/ by approx. 75%. For the product SM 58 LW 11, the fracture toughness was measured on pieces taken from different parts of a large cylinder to investigate the effects of segregation phenomena and of partial crystallization and formation of small cristobalite inclusions which decrease K/sub Ic/ by approx. 25%.
Date: January 1, 1983
Creator: Matzke, H.; Kahl, L.; Routbort, J.L. & Saidl, J.
Partner: UNT Libraries Government Documents Department

Fabrication of isotopic heat and radiation sources for the Federal Republic of Germany

Description: Pacific Northwest Laboratory (PNL) has filled 30 German-made canisters with highly radioactive borosilicate glass. These canisters, containing specified amounts of /sup 137/Cs and /sup 90/Sr, will be sealed using a gas tungsten arc welder and will be decontaminated to nonsmearable limits using an electropolishing system. They are to be characterized in a series of nondestructive tests: surface dose rate measurement, axial gamma scanning, canister mass determination, and canister surface temperature measurement. The canisters will then be transported to the Asse Salt Mine located in the Federal Republic of Germany (FRG) for a 5-year repository testing program. 3 refs., 2 figs., 1 tab.
Date: September 1, 1987
Creator: McElroy, J.L.; Holton, L.K. Jr.; Burkholder, H.C.; Bryan, G.H. & Minor, J.E.
Partner: UNT Libraries Government Documents Department

Spin-polarised band theory at finite temperatures

Description: Starting from a Spin-Density functional description of electrons in a potentially ferromagnetic metal and the notion of temporarily broken ergodicity, a method is derived for performing finite temperature spin-polarized band theory with random local moment orientations. Formally, it is based on the KKR-CPA theory for randomly distributed spin-polarized scattering centers on a regular lattice. It is shown how the theory can lead to finite moments above the transition temperature, T/sub c/, and a Curie-Weiss law. We discuss the results of self-consistent spin-polarized KKR-CPA calculations in the disordered local moment (DLM) state for Fe, Co, Ni, and Cr.
Date: January 1, 1983
Creator: Gyorffy, B.L.; Kollar, J.; Pindor, A.J.; Staunton, J.; Stocks, G.M. & Winter, H.
Partner: UNT Libraries Government Documents Department

Vibrational experiments at the HDR (Heissdampfreaktor): SHAG results and planning for SHAM

Description: As part of the second phase of vibrational/earthquake investigations at the HDR (Heissdampfreaktor) Test Facility in Kahl/Main, FRG, high-level shaker tests (SHAG) were performed during June and July 1986 using a coast-down shaker capable of generating 1000 tons of force. The purpose of these experiments was to investigate full-scale structural response, soil/structure interaction, and piping and equipment response under strong excitation conditions. While global safety considerations imposed load limitations, the HDR soil/structure system was nevertheless tested to incipient failure. The performance of pipe support systems in as many as seven different multiple support pipe hanger configurations, ranging from flexible to stiff systems, was evaluated in the tests. Data obtained in the tests are used to validate analysis methods. The vibrational/earthquake investigations at the HDR are continuing with the SHAM experiments, planned for the spring of 1988. In these experiments the VKL piping loop will be subjected to direct multiple-point excitation at extremely high levels. The objective is to investigate different pipe support configurations at extreme loading, to establish seismic margins for piping, and to investigate possible failure/plastification modes in an in situ piping system.
Date: January 1, 1987
Creator: Kot, C.A.; Malcher, L. & Steinhilber, H.
Partner: UNT Libraries Government Documents Department