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Analytic method for calculating the time--temperature history of metal foils under pulsed irradiation and a Gaussian beam profile

Description: Utilization of a pulsed radiation source such as the Clinton P. Anderson Meson Physics Facility (LAMPF) for materials science studies requires knowledge of the time--temperature history of a subject metal foil. An analytic solution was derived to a two-dimensional heat flow equation, incorporating the LAMPF time structure and the LAMPF Gaussian beam spot profile. This calculational method is useful in designing experimental systems for materials science studies and can be done on a Hewlett--Pac… more
Date: May 1, 1979
Creator: Kmetyk, L. N. & Sommer, W. F.
Partner: UNT Libraries Government Documents Department
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RELAP5 assessment: LOFT turbine trip L6-7/L9-2

Description: The RELAP5 independent assessment project at Sandia National Laboratories is part of an overall effort funded by the NRC to determine the ability of various systems codes to predict the detailed thermal; hydraulic response of LWRs during accident and off-normal conditions. The RELAP5/MOD1 code is being assessed at SNLA against test data from various integral and separate effects test facilities. As part of this assessment matrix, a turbine trip rapid cooldown transient performed at the LOFT tes… more
Date: July 1, 1983
Creator: Thompson, S. L. & Kmetyk, L. N.
Partner: UNT Libraries Government Documents Department
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Analytic and experimental decay heat determinations of 800-MeV proton irradiated aluminum

Description: Postirradiation radiochemistry analysis of 800-MeV proton irradiated ultrahigh purity aluminum has been done with standard gamma-ray counting equipment determining the Na/sup 22/ activity in the activated aluminum. Results are compared to predicted values obtained from CINDER, a general nuclide depletion and fission-product code. This program can be used easily to calculate the activity of materials under arbitrary irradiation, provided that the source terms for the various radionuclides produc… more
Date: October 1, 1981
Creator: Kmetyk, L. N. & Sommer, W. F.
Partner: UNT Libraries Government Documents Department
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Air ingression calculations for selected plant transients using MELCOR

Description: Two sets of MELCOR calculations have been completed studying the effects of air ingression on the consequences of various severe accident scenarios. One set of calculations analyzed a station blackout with surge line failure prior to vessel breach, starting from nominal operating conditions; the other set of calculations analyzed a station blackout occurring during shutdown (refueling) conditions. Both sets of analyses were for the Surry plant, a three-loop Westinghouse PWR. For both accident s… more
Date: January 1, 1994
Creator: Kmetyk, L. N.
Partner: UNT Libraries Government Documents Department
open access

MELCOR 1. 8. 1 assessment: LACE aerosol experiment LA4

Description: The MELCOR code has been used to simulate LACE aerosol experiment LA4. In this test, the behavior of single- and double-component, hygroscopic and nonhygroscopic, aerosols in a condensing environment was monitored. Results are compared to experimental data, and to CONTAIN calculations. Sensitivity studies have been done on time step effects and machine dependencies; thermal/hydraulic parameters such as condensation on heat structures and on pool surface, and radiation heat transfer; and aerosol… more
Date: September 1, 1991
Creator: Kmetyk, L. N.
Partner: UNT Libraries Government Documents Department
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Effect of cyclic pulsed temperature on void growth in metals during irradiation

Description: The analysis of Brailsford and Bullough on radiation-produced point defect transport to lattice sinks and the analysis of Ghoniem and Kulcinski of pulsed radiation have been extended to include the effects of radiation-induced temperature oscillations. We have already shown in earlier papers that these temperature pulses enhance void growth if the ambient temperature is below the peak swelling temperature and, conversely, decrease void growth when the ambient temperature is above the peak swell… more
Date: January 1, 1981
Creator: Kmetyk, L. N.; Sommer, W. F. & Weertman, J.
Partner: UNT Libraries Government Documents Department
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MELCOR 1.8.3 assessment: GE large vessel blowdown and level swell experiments

Description: MELCOR is a fully integrated, engineering-level computer code, being developed at Sandia National Laboratories for the USNRC, that models the entire spectrum of severe accident phenomena in a unified framework for both BWRs and PWRS. As part of an ongoing assessment program, the MELCOR computer code has been used to analyze a series of blowdown tests performed in the early 1980s at General Electric. The GE large vessel blowdown and level swell experiments are a set of primary system thermal/hyd… more
Date: July 1, 1994
Creator: Kmetyk, L. N.
Partner: UNT Libraries Government Documents Department
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MELCOR 1.8.2 calculations of selected sequences for the ABWR

Description: This report summarizes the results from MELCOR calculations of severe accident sequences in the ABWR and presents comparisons with MAAP calculations for the same sequences. MELCOR was run for two low-pressure and three high-pressure sequences to identify the materials which enter containment and are available for release to the environment (source terms), to study the potential effects of core-concrete interaction, and to obtain event timings during each sequence; the source terms include fissi… more
Date: July 1, 1994
Creator: Kmetyk, L. N.
Partner: UNT Libraries Government Documents Department
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MELCOR 1.8.2 Assessment: IET direct containment heating tests

Description: MELCOR is a fully integrated, engineering-level computer code, being developed at Sandia National Laboratories for the USNRC, that models the entire spectrum of severe accident phenomena in a unified framework for both BWRs and PWRS. As part of an ongoing assessment program, the MELCOR computer code has been used to analyze several of the IET direct containment heating experiments done at 1:10 linear scale in the Surtsey test facility at Sandia and at 1:40 linear scale in the corium-water therm… more
Date: October 1, 1993
Creator: Kmetyk, L. N.
Partner: UNT Libraries Government Documents Department
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MELCOR 1.8.3 assessment: CSE containment spray experiments

Description: MELCOR is a fully integrated, engineering-level computer code, being developed at Sandia National Laboratories for the USNRC, that models the entire spectrum of severe accident phenomena in a unified framework for both BWRs and PWRS. As part, of an ongoing assessment program, the MELCOR computer code has been used to analyze a series of containment spray tests performed in the Containment Systems Experiment (CSE) vessel to evaluate the performance of aqueous sprays as a means of decontaminating… more
Date: December 1, 1994
Creator: Kmetyk, L. N.
Partner: UNT Libraries Government Documents Department
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CTH analyses of steel rod penetration into aluminum and concrete targets with comparisons to experimental data

Description: Calculational results are presented here for a class of intermediate-velocity penetration problems. The problems of interest involve penetration of moderate-strength target materials by high-strength projectiles. Two series of metal penetration experiments and a series of concrete slab perforation tests were simulated in this study. The computer code used for the calculations was the CTH code, which employs a recently-developed ``boundary layer`` algorithm for treating penetration problems such… more
Date: October 1, 1994
Creator: Kmetyk, L. N. & Yarrington, P.
Partner: UNT Libraries Government Documents Department
open access

Use of the LAMPF accelerator as a fusion materials-radiation facility

Description: Materials for fusion applications will be subjected to radiation that produces large amounts of transmutation product gases such H and He, as well as others. These gaseous products can have a marked influence on material mechanical properties as they affect the microstructural evolution of the material. Previous calculations by others have shown that the 800 MeV proton beam at the Clinton P. Anderson Los Alamos Meson Physics Facility (LAMPF) will produce gaseous transmutation products in amount… more
Date: January 1, 1981
Creator: Sommer, W. F.; Kmetyk, L. N.; Green, W. V. & Damjanovich, R.
Partner: UNT Libraries Government Documents Department
open access

L3 (33) an analytic comparison of the effect of steady state and cyclic pulsed radiation on void growth and swelling

Description: The analysis of Ghoniem and Kulcinski of pulsed radiation was extended to include the effects of temperature oscillations and multiple pulses. Multiple pulses are required before the vacancy concentration stabilizes to an oscillation between limits. Then void growth proceeds at a nearly uniform rate. Point defect recombination plays only a minor role, but temperature oscillations play a significant role.
Date: January 1, 1979
Creator: Kmetyk, L. N.; Sommer, W. F.; Weertman, J. & Green, W. V.
Partner: UNT Libraries Government Documents Department
open access

Void growth and swelling for cyclic pulsed radiation

Description: The analysis of Ghoniem and Kulcinski of a single radiation pulse has been extended to include the effects of temperature oscillations and multiple pulses by coupling six simultaneous nonlinear ordinary differential equations for point defect concentrations and sink strengths with a heat equation governing radiation-produced temperature fluctuations. The pulsed irradiation considered is that of the 800 MeV proton beam at the Clinton P. Anderson Meson Physics Facility (LAMPF), and numerical calc… more
Date: September 1, 1980
Creator: Kmetyk, L. N.; Weertman, J.; Green, W. V. & Sommer, W. F.
Partner: UNT Libraries Government Documents Department
open access

MELCOR technical assessment at SNL

Description: MELCOR is a fully integrated, engineering-level computer code that models the progression of severe accidents in light water reactor (LWR) nuclear power plants, which is being developed at Sandia National Laboratories for the US Nuclear Regulatory Commission (US-NRC). The entire spectrum of severe accident phenomena, including reactor coolant system and containment thermal/hydraulic response, core heatup, degradation and relocation, and fission product release and transport, is treated in MELCO… more
Date: December 1, 1993
Creator: Kmetyk, L. N. & Tautges, T. J.
Partner: UNT Libraries Government Documents Department
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Evaluation of potential severe accidents during low power and shutdown operations at Grand Gulf, Unit 1: Evaluation of severe accident risks for plant operational state 5 during a refueling outage. Supporting MELCOR calculations, Volume 6, Part 2

Description: To gain a better understanding of the risk significance of low power and shutdown modes of operation, the Office of Nuclear Regulatory Research at the NRC established programs to investigate the likelihood and severity of postulated accidents that could occur during low power and shutdown (LP&S) modes of operation at commercial nuclear power plants. To investigate the likelihood of severe core damage accidents during off power conditions, probabilistic risk assessments (PRAs) were performed for… more
Date: March 1, 1995
Creator: Kmetyk, L. N. & Brown, T. D.
Partner: UNT Libraries Government Documents Department
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MELCOR 1.8.2 assessment: Aerosol experiments ABCOVE AB5, AB6, AB7, and LACE LA2

Description: The MELCOR computer code has been used to model four of the large-scale aerosol behavior experiments conducted in the Containment System Test Facility (CSTF) vessel. Tests AB5, AB6 and AB7 of the ABCOVE program simulate the dry aerosol conditions during a hypothetical severe accident in an LMFBR. Test LA2 of the LACE program simulates aerosol behavior in a condensing steam environment during a postulated severe accident in an LWR with failure to isolate the containment. The comparison of code r… more
Date: October 1, 1994
Creator: Souto, F. J.; Haskin, F. E. & Kmetyk, L. N.
Partner: UNT Libraries Government Documents Department
open access

The influence of phase changes on debris-cloud interactions with protected structures

Description: The physical state of the debris cloud generated by the interaction of a projectile with a thin target depends on the energy balance associated with above the sound speeds of the impact event. At impact velocities well materials involved, the cloud is expected to be primarily molten, but with some vapor present. A series of numerical calculations using the multi-dimensional finite-difference hydrocode CTH has been used to evaluate the effect of phase changes (i.e., different vapor fractions) on… more
Date: May 16, 1994
Creator: Lawrence, R. J.; Kmetyk, L. N. & Chhabildas, L. C.
Partner: UNT Libraries Government Documents Department
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Ground shock from multiple earth penetrator bursts: Effects for hexagonal weapon arrays

Description: Calculations have been performed with the HULL hydrocode to study ground shock effects for multiple earth penetrator weapon (EPW) bursts in hexagonal-close-packed (HCP) arrays. Several different calculational approaches were used to treat this problem. The first simulations involved two-dimensional (2D) calculations, where the hexagonal cross-section of a unit-cell in an effectively-infinite HCP array was approximated by an inscribed cylinder. Those calculations showed substantial ground shock … more
Date: August 1, 1990
Creator: Kmetyk, L. N. & Yarrington, P.
Partner: UNT Libraries Government Documents Department
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Effect of phase change in a debris cloud on a backwall structure

Description: The physical state of a debris cloud generated upon impact of a thin flier plate with a thin bumper depends on the impact velocity. At impact velocities of 10km/s, the debris cloud is expected to be primarily molten with some vapor present. A series of calculations using the finite-difference code CTH has been used to evaluate the effect of phase change (i.e., higher concentrations of vapor) in debris clouds and their subsequent impact on a backwall structure. In these calculations, the higher … more
Date: July 1, 1993
Creator: Kmetyk, L. N.; Chhabildas, L. C.; Boslough, M. B. & Lawrence, R. J.
Partner: UNT Libraries Government Documents Department
open access

Launch capabilities to 16 km/s

Description: A systematic study is described that has led to the successful launch of thin flier-plates to velocities of 16 km/s. In this paper, the authors describe a novel technique that has been implemented to enhance the performance of the Sandia Hyper Velocity Launcher (HVL). This technique of creating an impact-generated acceleration reservoir, has allowed the launch of 0.5 mm to 1.0 mm thick titanium (Ti-6Al-4V) and aluminum (6061-T6) alloy plates to record velocities up to 15.8 km/s. These are the h… more
Date: August 1, 1995
Creator: Chhabildas, L. C.; Kmetyk, L. N.; Reinhart, W. D. & Hall, C. A.
Partner: UNT Libraries Government Documents Department
open access

Evaluation of potential severe accidents during low power and shutdown operations at Grand Gulf, Unit 1: Evaluation of severe accident risks for plant operational state 5 during a refueling outage. Main report and appendices, Volume 6, Part 1

Description: Traditionally, probabilistic risk assessments (PRAS) of severe accidents in nuclear power plants have considered initiating events potentially occurring only during full power operation. Recent studies and operational experience have, however, implied that accidents during low power and shutdown could be significant contributors to risk. In response to this concern, in 1989 the Nuclear Regulatory Commission (NRC) initiated an extensive program to carefully examine the potential risks during low… more
Date: March 1995
Creator: Brown, T. D.; Kmetyk, L. N.; Whitehead, D.; Miller, L.; Forester, J. & Johnson, J.
Partner: UNT Libraries Government Documents Department
open access

MELCOR 1.8.2 assessment: Surry PWR TMLB` (with a DCH study)

Description: MELCOR is a fully integrated, engineering-level computer code, being developed at Sandia National Laboratories for the USNRC. This code models the entire spectrum of severe accident phenomena in a unified framework for both BWRs and PWRs. As part of an ongoing assessment program, the MELCOR computer code has been used to analyze a station blackout transient in Surry, a three-loop Westinghouse PWR. Basecase results obtained with MELCOR 1.8.2 are presented, and compared to earlier results for the… more
Date: February 1, 1994
Creator: Kmetyk, L. N.; Cole, R. K., Jr.; Smith, R. C.; Summers, R. M. & Thompson, S. L.
Partner: UNT Libraries Government Documents Department
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