Adaptive Mesh Refinement for 1-Dimensional Gas Dynamics (open access)

Adaptive Mesh Refinement for 1-Dimensional Gas Dynamics

We consider the solution of the one-dimensional equation of gas-dynamics. Accurate numerical solutions are difficult to obtain on a given spatial mesh because of the existence of physical regions where components of the exact solution are either discontinuous or have large gradient changes. Numerical methods treat these phenomena in a variety of ways. In this paper, the method of adaptive mesh refinement is used. A thorough description of this method for general hyperbolic systems is given elsewhere and only properties of the method pertinent to the system are elaborated.
Date: 1982-08~
Creator: Hedstrom, Gerald; Rodrigue, Garry; Berger, Marsha & Oliger, Joseph
System: The UNT Digital Library
Science and art in heavy-ion collisions (open access)

Science and art in heavy-ion collisions

One of the more intriguing phenomena discovered in heavy-ion physics is the seeming appearance of high energy structure in the excitation spectra of inelastically scattered heavy ions. For reasons illustrated, these may well be a phenomena unique to heavy ions and their explanation perhaps unique to TDHF.
Date: August 9, 1982
Creator: Weiss, M.S.
System: The UNT Digital Library
Hybrid charged-particle guide for studying (n, charged particle) reactions (open access)

Hybrid charged-particle guide for studying (n, charged particle) reactions

Charged-particle transport systems consisting of magnetic quadrupole lenses have been employed in recent years in the study of (n, charged particle) reactions. We have completed a new transport system that is based both on magnetic lenses as well as electrostatic fields. The magnetic focusing of this charged-particle guide is provided by six magnetic quadrupole lenses arranged in a CDCCDC sequence (in the vertical plane). The electrostatic field is produced by a wire at high voltage which stretches the length of the guide and is physically at the center of the magnetic axis. The magnetic lenses are used for charged particles above 5 MeV; the electrostatic guide is used for lower energies. This hybrid system possesses the excellent focusing and background rejection properties of other magnetic systems. For low energy charged-particles, the electrostatic transport avoids the narrow band-passes in charged-particle energy which are a problem with purely magnetic transport systems. This system is installed at the LLNL Cyclograaff facility for the study of (n, charged particle) reactions at neutron energies up to 35 MeV.
Date: August 25, 1982
Creator: Haight, R. C.; White, R. M. & Zinkle, S. J.
System: The UNT Digital Library
Streaked x-ray microscopy of laser-fusion targets (open access)

Streaked x-ray microscopy of laser-fusion targets

An ultrafast soft x-ray streak camera has been coupled to a Wolter axisymmetric x-ray microscope. This system was used to observe the dynamics of laser fusion targets both in self emission and backlit by laser produced x-ray sources. Spatial resolution was 7 ..mu..m and temporal resolution was 20 ps. Data is presented showing the ablative acceleration of foils to velocities near 10/sup 7/ cm/sec and the collision of an accelerated foil with a second foil, observed using 3 keV streaked x-ray backlighting. Good agreement was found between hydrocode simulations, simple models of the ablative acceleration and the observed velocities of the carbon foils.
Date: August 1, 1982
Creator: Price, R. H.; Campbell, E. M.; Rosen, M. D.; Auerbach, J. M.; Phillion, D. W.; Whitlock, R. R. et al.
System: The UNT Digital Library
Stochastic basis for curve shape, RBE and temporal dependence (open access)

Stochastic basis for curve shape, RBE and temporal dependence

This paper uses biophysical-microdosimetric quantities, measured in a physical surrogate or phantom cell, to explain the shape of absorbed dose-quantal cell response curves, the role of radiation quality and the influence of dose rate. Responses expected are explored first in simple autonomous cell systems, followed by increasingly-complex systems. Complications seen with increasingly-complex systems appear to be confined largely to the higher dose and dose rate ranges.
Date: August 10, 1982
Creator: Bond, V.P.
System: The UNT Digital Library
New wiggler beam line for SSRL (open access)

New wiggler beam line for SSRL

A new high-intensity-beam line with a wiggler magnet source is described. This project, in final stages of design, is a joint effort between Lawrence Berkeley Laboratory (LBL), the Exxon Research and Engineering Company (EXXON), and the Stanford Synchrotron Radiation Laboratory (SSRL). Installation at SSRL will begin in the summer of 1982. The goal of this project is to provide extremely high-brightness synchrotron radiation beams over a broad spectral range from 50 eV to 40 keV. The radiation source is a 27 period (i.e., 55 pole) permanent magnet wiggler of a new design. The wiggler utilizes rare-earth cobalt (REC) material in the steel hybrid configuration to achieve high magnetic fields with short periods. An analysis has been made of the polarization, angular distribution and power density of the radiation produced by the wiggler. Details of the wiggler design are presented. The magnet is outside a thin walled (1mm) variable gap stainless steel vacuum chamber. The chamber gap will be opened to 1.8 cm for beam injection into SPEAR and then closed to 1.0 cm (or less) for operation. Five remotely controlled drives are provided; to change the wiggler gap, to change the vacuum chamber aperture and to position the wiggler. Details …
Date: August 1, 1982
Creator: Hoyer, E.
System: The UNT Digital Library
Hydrogen in MgO crystals thermochemically reduced at very high temperatures (open access)

Hydrogen in MgO crystals thermochemically reduced at very high temperatures

Evidence is presented that H/sup -/ ions are the main electron traps responsible for the long-lived luminescence of the F centers observed at 2.3 eV in thermochemically reduced MgO crystals.
Date: August 1, 1982
Creator: Chen, Y.
System: The UNT Digital Library
Production characteristics of some Cerro Prieto wells (open access)

Production characteristics of some Cerro Prieto wells

An areal distribution of heat and mass production in the Cerro Prieto field has been presented for two different times to determine the initial state of the ..cap alpha.. and ..beta.. aquifers and the behavior of the field under production. It was found that, initially, the ..cap alpha.. and ..beta.. aquifers were hot and very hot respectively. Cold boundaries to the field were found to be located toward the west and northeast. Initially, fluid production from most wells was very high. M-53 and some wells southeast of Fault H produced very hot fluids at very high rates. Production from most wells declined over the years, possibly due to scaling in the wellbore, reduced recharge to the aquifer, high resistance to flow due to silica precipitation in the reservoir pores and/or relative permeability effects in the two-phase regions surrounding the wells. In most wells fluid enthalpies declined over the years, perhaps due to mixing with colder waters either drawn in from upper strata and/or from the cold lateral boundaries depending upon well location.
Date: August 1, 1982
Creator: Goyal, K. P.; Halfman, S. E.; Truesdell, A. H. & Howard, J. H.
System: The UNT Digital Library
Inertial-confinement-fusion targets (open access)

Inertial-confinement-fusion targets

Much of the research in laser fusion has been done using simple ball on-stalk targets filled with a deuterium-tritium mixture. The targets operated in the exploding pusher mode in which the laser energy was delivered in a very short time (approx. 100 ps or less) and was absorbed by the glass wall of the target. The high energy density in the glass literally exploded the shell with the inward moving glass compressing the DT fuel to high temperatures and moderate densities. Temperatures achieved were high enough to produce DT reactions and accompanying thermonuclear neutrons and alpha particles. The primary criteria imposed on the target builders were: (1) wall thickness, (2) sphere diameter, and (3) fuel in the sphere.
Date: August 10, 1982
Creator: Hendricks, C.D.
System: The UNT Digital Library
Computing reliability from warranty (open access)

Computing reliability from warranty

In the planned vacuum system of the new world's largest accelerator being built at Brookhaven National Laoratory the core consists of a great number of identical components. It is known that the vacuum system will fail if a specific number or more of the identical components which are adjacent to each other fail. The components are placed along a ring. In order to assure that the required minimum reliability of the vacuum system in a given period of time is obtained, a minimum warranty request needs to be figured out and forwarded to the manufacturer of the components. The purpose of this work is to determine this minimum warranty request.
Date: August 1, 1982
Creator: Kao, S.C.
System: The UNT Digital Library
Vector meson backgrounds at high-energy e anti e machines (open access)

Vector meson backgrounds at high-energy e anti e machines

This note presents cross sections for e anti e ..-->.. W/sup -/W/sup +/, ZZ, Z..gamma.. at high energies. The first of these is available in the LEP reports and elsewhere, but the remaining two seem to be unavailable. These cross-sections represent a background to potentially interesting physics on mass scales of order 1 TeV. They are large due to t channel lepton exchange diagrams.
Date: August 1, 1982
Creator: Hinchliffe, I.
System: The UNT Digital Library
Neutron scattering review: magnetic studies (open access)

Neutron scattering review: magnetic studies

A brief review of the contributions that neutron scattering has made to studies of magnetism is given. (WHK)
Date: August 1, 1982
Creator: Koehler, W.C.
System: The UNT Digital Library
Phonons and their interactions (open access)

Phonons and their interactions

The phonon energy spectra nu(vector q) of crystalline materials contains key information about the interatomic interactions. However, it is generally not possible to fully understand the phonon spectra without also understanding the influence on phonon energies and lifetimes caused by interactions with defects, electrons and other excitations. The study of several of these types of interactions have grown over the years so as to now constitute subfields of solid state physics and the contributions of neutron scattering research to each has been, if not of paramount importance, at least very significant. In the present review we can merely touch on a few highlights. Perhaps the largest research effort is expended on electron-phonon interactions. These interactions are, of course, fundamental to the properties of metallic solids. They are seen in the phonon nu(vector q) of metals in a wide variety of effects. We shall mention three: the relatively small fine structure produced by Kohn singularities, large anomalies and phonon lifetimes measured in some superconductors and in materials with fluctuating valence.
Date: August 1, 1982
Creator: Nicklow, R. M.
System: The UNT Digital Library
Effect of foundation embedment on the seismic response of a high temperature gas-cooled reactor plant (open access)

Effect of foundation embedment on the seismic response of a high temperature gas-cooled reactor plant

The effects of soil-structure interaction during seismic events upon the dynamic response of a High Temperature Gas-Cooled Reactor Plant (HTGR) have been investigated for both surface-founded and embedded basemats. The influence from foundation embedment has been quantitatively assessed through a series of theoretical studies on plants of various sizes. The surface-founded analyses were performed using frequency-independent soil impedance parameters; while the embedded plant analyses utilized finite element models simulated on the FLUSH computer program. The seismic response of the surface-founded plants has been used to establish the standard-site design in-structure response spectra. These analyses were performed by using the linear modal formulation based on conventional soil stiffness and damping values. Numerical results are presented in terms of in-structure response spectra along with other pertinent seismic load data at key levels of the plant. Analysis techniques for future studies using viscoelastic halfspace representation and inelastic finite element modeling for soil are also discussed.
Date: August 1, 1982
Creator: Lee, T. H.; Thompson, R. W. & Charman, C. M.
System: The UNT Digital Library
Heat transfer between immiscible liquids enhanced by gas bubbling. [PWR; BWR] (open access)

Heat transfer between immiscible liquids enhanced by gas bubbling. [PWR; BWR]

The phenomena of core-concrete interactions impact upon containment integrity of light water reactors (LWR) following postulated complete meltdown of the core by containment pressurization, production of combustible gases, and basemat penetration. Experiments have been performed with non-reactor materials to investigate one aspect of this problem, heat transfer between overlying immiscible liquids whose interface is disturbed by a transverse non-condensable gas flux emanating from below. Hydrodynamic studies have been performed to test a criterion for onset of entrainment due to bubbling through the interface and subsequent heat transfer studies were performed to assess the effect of bubbling on interfacial heat transfer rates, both with and without bubble induced entrainment. Non-entraining interfacial heat transfer data with mercury-water/oil fluid pairs were observed to be bounded from below within a factor of two to three by the Szekeley surface renewal heat transfer model. However heat transfer data for fluid pairs which are found to entrain (water-oil), believed to be characteristic of molten reactor core-concrete conditions, were measured to be up to two orders of magnitude greater than surface renewal predictions and are calculated by a simple entrainment heat transfer model.
Date: August 1, 1982
Creator: Greene, G. A.; Schwarz, C. E.; Klages, J. & Klein, J.
System: The UNT Digital Library
Transient core-debris bed heat-removal experiments and analysis. [PWR; BWR] (open access)

Transient core-debris bed heat-removal experiments and analysis. [PWR; BWR]

An experimental investigation is reported of the thermal interaction between superheated core debris and water during postulated light-water reactor degraded core accidents. Data are presented for the heat transfer characteristics of packed beds of 3 mm spheres which are cooled by overlying pools of water. Results of transient bed temperature and steam flow rate measurements are presented for bed heights in the range 218 mm-433 mm and initial particle bed temperatures between 530K and 972K. Results display a two-part sequential quench process. Initial frontal cooling leaves pockets or channels of unquenched spheres. Data suggest that heat transfer process is limited by a mechanism of countercurrent two-phase flow. An analytical model which combines a bed energy equation with either a quasisteady version of the Lipinski debris bed model or a critical heat flux model reasonably well predicts the characteristic features of the bed quench process. Implications with respect to reactor safety are discussed.
Date: August 1, 1982
Creator: Ginsberg, T.; Klein, J.; Klages, J.; Schwarz, C. E. & Chen, J. C.
System: The UNT Digital Library
Recent progress in commensurate-incommensurate phase transformations. [Hg/sub 3/-delta AsF/sub 6/; 2H polytype of TaSe/sub 2/] (open access)

Recent progress in commensurate-incommensurate phase transformations. [Hg/sub 3/-delta AsF/sub 6/; 2H polytype of TaSe/sub 2/]

Three topics are discussed. (1) the nature of long wavelength excitations in Hg/sub 3/-delta AsF/sub 6/, where gapless excitations in addition to the conventional acoustic modes are observed. (2) Thiourea, in which new commensurate phases can be induced by an external electric field. (3) Discommensurations in 2HTaSe/sub 2/, where recent electron diffraction and high resolution x-ray data combine with neutron results to establish a quite complex and subtle behavior. 9 figures.
Date: August 1, 1982
Creator: Axe, J.D.
System: The UNT Digital Library
Thermochemical energy storage and transport (open access)

Thermochemical energy storage and transport

Feasibility studies of thermochemical energy storage and transport (TEST) are described. Cases studied include a large central receiver heat utility and a small industrial process heat application with distributed parabolic dish solar collectors. TEST does not appear to be generally cost-effective; however, there are special cases of cost-effectiveness. The overall recommendation is that research on thermochemical processes should emphasize the manufacture of renewable fuels using solar energy and the search for more cost-effective TEST systems.
Date: August 1, 1982
Creator: Nix, R.G.
System: The UNT Digital Library
Gnome site decontamination and decommissioning project (open access)

Gnome site decontamination and decommissioning project

In July 1977, DOE/Headquarters directed DOE/NV to design a decontamination and decommissioning plan for the Gnome site, 48 kilometers southeast of Carlsbad, New Mexico. The plan incorporated three distinct phases. During Phase I, both aerial and ground radiological surveys were conducted on the site. Radiological decontamination criteria were established, and a decontamination plan was developed based on the radiological survey results. During Phase II, site preparatory and rehabilitation work was completed. The actual land area decontamination was accomplished during Phase III with conventional earthmoving equipment. A gravity water injection system deposited 36,700 metric tons of contaminated soil and salt in the Gnome cavity. After completion of the decontamination and decommissioning operations, the Gnome site was returned to the Bureau of Land Management for unrestricted surface use.
Date: August 1982
Creator: Orcutt, J. A. & Sorom, E. R.
System: The UNT Digital Library
Industry initiatives in impact mitigation (open access)

Industry initiatives in impact mitigation

The author concludes that mitigation is the focus of conflicting opinions regarding responsibility, strategy, and effort. There are no hard, fast, or tried and true rules for company involvement in mitigation efforts. Each mitigation effort must be tailored and negotiated to match the unique characteristics of individual projects and circumstances of specific locales. Companies must assume financial responsibility for the temporary impacts and area needs created by their projects. They must also offer financial and technical assistance to impact areas, not just the host political jurisdiction, when local, state, federal, and special fund sources of revenue or technical assistance are not available or insufficient. But, local, state, and federal governments must also recognize their responsibilities and make adjustments in tax jurisdiction boundaries and disbursement formulas so that impacted areas are properly defined and receive an adequate share of lease, royalty, severance tax, permit fee, special use and service charges, and sales tax payments. Laws need to allow innovative uses of tax pre-payments, housing mortgage bonds, changeable debt and bounding limits, industrial loans with delayed prepayment, and revised revenue assistance formulas. Enabling legislation is required in most states to allow impact areas to negotiate the mitigation efforts. A review of 7 …
Date: August 1, 1982
Creator: Metz, W.C.
System: The UNT Digital Library
Small-angle elastic and inelastic neutron scattering in Fe/sub 0/ /sub 7/Al/sub 0/ /sub 3/ (open access)

Small-angle elastic and inelastic neutron scattering in Fe/sub 0/ /sub 7/Al/sub 0/ /sub 3/

None
Date: August 1, 1982
Creator: Motoya, K. & Shapiro, S.M.
System: The UNT Digital Library
Prediction of reinjection effects on the Cerro Prieto geothermal system (open access)

Prediction of reinjection effects on the Cerro Prieto geothermal system

The response of the Cerro Prieto geothermal field to different reinjection schemes is predicted using a two-dimensional vertical reservoir model with single- or two-phase flow. The advance of cold fronts and pressure changes in the system associated with the inection operations are computed, taking into consideration the geologic characteristics of the field. The effects of well location, depth, and rates of injection are analyzed. Results indicate that significant pressure maintenance effects may be realized in a carefully designed reinjection operation.
Date: August 10, 1982
Creator: Tsang, C. F.; Mangold, D. C.; Doughty, C. & Lippmann, M. J.
System: The UNT Digital Library
Volatile fission-product source term evaluation using the fastgrass comptuer code. [PWR; BWR] (open access)

Volatile fission-product source term evaluation using the fastgrass comptuer code. [PWR; BWR]

As the noble gases play a major role in establishing the interconnection of escape routes from the interior to the exterior of nuclear reactor fuel, a realistic description of the release of volatile fission products (VFPs) must a priori include a realistic description of fission-gas release and swelling. The steady-state and transient gas release and swelling subroutine, FASTGRASS, has been modified to include a mechanistic description of behavior of VFPs (I, Cs, CsI, Cs/sub 2/MoO/sub 4/, and Cs/sub 2/UO/sub 4/). Phenomena modeled are the chemical reactions between the VFPs, VFP migration through the fuel, and VFP interaction with the noble gases. This paper will describe calculations performed with FASTGRASS to describe the release of noble gases, I, Cs, and CsI from LWR fuel during steady-state and power-ramping conditions. Key issues that are addressed in the analysis are the effects of (a) VFP chemistry, (b) various assumptions concerning mechanisms of VFP migration through solid UO/sub 2/, (c) fission-gas behavior, and (d) accident scenario on the chemical form of iodine and the rate of iodine release from water-reactor fuel.
Date: August 1, 1982
Creator: Rest, J.
System: The UNT Digital Library
Electrodeless drift chambers with 50-cm drift distance (open access)

Electrodeless drift chambers with 50-cm drift distance

The electrodeless drift-chamber technique is potentially very useful in applications requiring the drifting of ionization in gas over long distances in narrow channels. Chamber construction is simple and cheap; the technique is well suited to very large detectors operating in low-rate environments. Prototype tests on planar chambers reveal excellent drifting characteristics after the initial charging, but show a substantial degradation of pulse height from cosmic rays over a two-week period. The loss of efficiency appears to be caused by excess charge buildup on the dielectric surfaces of the chamber. Several solutions are suggested.
Date: August 1982
Creator: Ayres, D. S. & Price, L. E.
System: The UNT Digital Library