Three-dimensional thermal analysis of a baseline spent fuel repository (open access)

Three-dimensional thermal analysis of a baseline spent fuel repository

A three-dimensional thermal analysis has been performed using finite difference techniques to determine the near-field response of a baseline spent fuel repository in a deep geologic salt medium. A baseline design incorporates previous thermal modeling experience and OWI recommendations for areal thermal loading in specifying the waste form properties, package details, and emplacement configuration. The base case in this thermal analysis considers one 10-year old PWR spent fuel assembly emplaced to yield a 36 kw/acre (8.9 w/m/sup 2/) loading. A unit cell model in an infinite array is used to simplify the problem and provide upper-bound temperatures. Boundary conditions are imposed which allow simulations to 1000 years. Variations studied include a comparison of ventilated and unventilated storage room conditions, emplacement packages with and without air gaps surrounding the canister, and room cool-down scenarios with ventilation following an unventilated state for retrieval purposes. At this low power level ventilating the emplacement room has an immediate cooling influence on the canister and effectively maintains the emplacement room floor near the temperature of the ventilating air. The annular gap separating the canister and sleeve causes the peak temperature of the canister surface to rise by 10/sup 0/F (5.6/sup 0/C) over that from a …
Date: June 5, 1980
Creator: Altenbach, T.J. & Lowry, W.E.
System: The UNT Digital Library
Inertial fusion research at Lawrence Livermore National Laboratory: program status and future applications (open access)

Inertial fusion research at Lawrence Livermore National Laboratory: program status and future applications

The objectives of the Lawrence Livermore National Laboratory (LLNL) Laser Fusion Program are to understand and develop the science and technology required to utilize inertial confinement fusion (ICF) for both military and commercial applications. The results of recent experiments are described. We point out the progress in our laser studies, where we continue to develop and test the concepts, components, and materials for present and future laser systems. While there are many potential commercial applications of ICF, we limit our discussions to electric power production.
Date: June 5, 1986
Creator: Meier, W. R. & Hogan, W. J.
System: The UNT Digital Library
New Evidence From Soudan 1 for Underground Muons Associated With Cygnus X-3 (open access)

New Evidence From Soudan 1 for Underground Muons Associated With Cygnus X-3

The Soudan 1 experiment has obtained additional evidence for underground muons associated with the x-ray pulsar Cygnus X-3. We report the preliminary analysis of data recorded during the October 1985 radio outburst of Cygnus X-3, which show a significant excess of muons for a narrow range of Cygnus X-3 phases.
Date: June 5, 1986
Creator: Ayres, D. S.
System: The UNT Digital Library
Nuclear performance optimization of the molten-salt fusion breeder (open access)

Nuclear performance optimization of the molten-salt fusion breeder

Improved nuclear analysis, including the treatment of resonance and spatial self-shielding, coupled with an optimization procedure, has resulted in an improved performance estimate for the molten salt blanket. Net U-233 breeding ratio ranges between 0.58 and 0.63, and blanket energy multiplication ranges between 1.8 and 1.9.
Date: June 5, 1986
Creator: Lee, J. D. & Bandini, B. R.
System: The UNT Digital Library
Psuedo-3D, isodensity and density profiles from fiber optic output of a MACH-130 air shock (open access)

Psuedo-3D, isodensity and density profiles from fiber optic output of a MACH-130 air shock

A modified Voitenko compressor generated a Mach-130 air shock in an outlet pipe open to the atmosphere. Fiber optics transmitted luminosity associated with propagation of the air shock to an external display board, which was scanned with a high-speed streaking camera. We describe the computerized microdensitometer scanning technique for converting the film records to pseudo-3D, isodensity, and density profiles. The isodensity contours can be displayed using different colors to facilitate analysis. This technique can achieve resolutions of 1 ns and 2 ..mu..m. We give examples of the pseudo-3D, isodensity, and density profile plots for the experiment. The microdensitometer output was digitized for input to data display programs run on a CDC 7600. These results were used to provide submicrosecond accuracy for shock propagation over a 5 m of the outlet pipes. In addition, we obtained information about gas flow behind the shock front. Other current or possible applications for the technique are measurement of: target implosion in laser fusion, flash x-ray data in hydrodynamic and ballistic experiments, temperature profiles for high energy (> 10/sup 5/ K) gas dynamics, and dynamic events in weapons testing.
Date: June 5, 1981
Creator: Dittmore, C.H. & Glenn, H.D.
System: The UNT Digital Library
TIBER II: an upgraded tokamak igntion/burn experimental reactor (open access)

TIBER II: an upgraded tokamak igntion/burn experimental reactor

We are disIgning a minimum-size Tokamak ignition/Burn Reactor (TIBER II). This design incorporates physics requirements, neutron wall loading and fluence parameters that will make it compatible with a nuclear testing mission. Reactor relevant physics will be tested by using current drive and steady-state operation. Although the design accommodates several current drive options, including neutral beams, the base case uses a combination of lower hybrid and electron-cyclotron radio frequency power. Minimum neutron shielding, compact structures, high magnet-current densities, and remotely maintainable vacuum seals, all contribute to the compact size.
Date: June 5, 1986
Creator: Henning, C. D.; Logan, B. G.; Perkins, L. J.; Barr, W. L.; Bulmer, R. H.; Devoto, R. S. et al.
System: The UNT Digital Library
Low energy x-ray spectrometer (open access)

Low energy x-ray spectrometer

A subkilovolt spectrometer has been produced to permit high-energy-resolution, time-dependent x-ray intensity measurements. The diffracting element is a curved mica (d = 9.95A) crystal. To preclude higher order (n > 1) diffractions, a carbon x-ray mirror that reflects only photons with energies less than approx. 1.1 keV is utilized ahead of the diffracting element. The nominal energy range of interest is 800 to 900 eV. The diffracted photons are detected by a gold-surface photoelectric diode designed to have a very good frequency response, and whose current is recorded on an oscilloscope. A thin, aluminium light barrier is placed between the diffracting crystal and the photoelectric diode detector to keep any uv generated on or scattered by the crystal from illuminating the detector. High spectral energy resolution is provided by many photocathodes between 8- and 50-eV wide placed serially along the diffracted x-ray beam at the detector position. The spectrometer was calibrated for energy and energy dispersion using the Ni L..cap alpha../sub 1/ /sub 2/ lines produced in the LLNL IONAC accelerator and in third order using a molybdenum target x-ray tube. For the latter calibration the carbon mirror was replaced by one surfaced with rhodium to raise the cut-off energy …
Date: June 5, 1981
Creator: Woodruff, W. R.
System: The UNT Digital Library
Including the effect of control strategy in solar load ratio calculations (open access)

Including the effect of control strategy in solar load ratio calculations

As originally developed, solar load ratio correlations for performance analysis of passive heating systems were intended for use only with a constant thermostat setpoint. The thermostat setpoint used in the method may be adjusted to account for the effect of heating from internal sources, but setback or shutdown strategies that are frequantly employed in both residential and commercial buildings were not allowed. A procedure for approximating the effect of various control strategies through use of an equivalent constant thermostat setpoint, T/sub ec/, has recently been developed at Los Alamos National Laboratory. The value of T/sub ec/ depends on the level and duration of thermostat settings used during the diurnal cycle and on the characteristic time constant is a function of the diurnal heat capacity of the building and its loss characteristics. The method described in this paper has been applied to a variety of passive solar buildings in two distinct climatic regions and was found to yield good accuracy when compared with detailed thermal network calculations.
Date: June 5, 1984
Creator: Wray, W. O. & Kosiewicz, C. E.
System: The UNT Digital Library