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Nonlinear interaction of fast particles with Alfven waves in toroidal plasmas

Description: A numerical algorithm to study the nonlinear, resonant interaction of fast particles with Alfven waves in tokamak geometry has been developed. The scope of the formalism is wide enough to describe the nonlinear evolution of fishbone modes, toroidicity-induced Alfven eigenmodes and ellipticity-induced Alfven eigenmodes, driven by both passing and trapped fast ions. When the instability is sufficiently weak, it is known that the wave-particle trapping nonlinearity will lead to mode saturation before wave-wave nonlinearities are appreciable. The spectrum of linear modes can thus be calculated using a magnetohydrodynamic normal-mode code, then nonlinearly evolved in time in an efficient way according to a two-time-scale Lagrangian dynamical wave model. The fast particle kinetic equation, including the effect of orbit nonlinearity arising from the mode perturbation, is simultaneously solved of the deviation, {delta}f = f {minus} f{sub 0}, from an initial analytic distribution f{sub 0}. High statistical resolution allows linear growth rates, frequency shifts, resonance broadening effects, and nonlinear saturation to be calculated quickly and precisely. The results have been applied to an ITER instability scenario. Results show that weakly-damped core-localized modes alone cause negligible alpha transport in ITER-like plasmas--even with growth rates one order of magnitude higher than expected values. However, the possibility of significant transport in reactor-type plasmas due to weakly unstable global modes remains an open question.
Date: December 17, 1996
Creator: Candy, J.; Borba, D.; Huysmans, G.T.A.; Kerner, W. & Berk, H.L.
Partner: UNT Libraries Government Documents Department

Electroabsorption and transport measurements and modeling in amorphous-silicon-based solar cells: Phase I technical progress report, 24 March 1998--23 March 1999

Description: This report describes work done by the Syracuse University during Phase 1 of this subcontract. Researchers performed work in the following areas: (1) In ``Electroabsorption measurements and built-in potentials in a-Si:H-based solar cells and devices'', researchers obtained an estimate of Vbi = 1.17 V in cells with a-SiGe:H absorber layers from United Solar Systems Corp. (2) In ``Solar cell modeling employing the AMPS computer program'', researchers began operating a simple AMPS modeling site and explored the effect of conduction bandtail width on Voc computed analytical approximations and the AMPS program. The quantitative differences between the two procedures are discussed. (3) In ``Drift mobility measurements in a-Si:H made with high hydrogen dilution'', researchers measured electron and hole mobilities in several n/i/Ni (semitransparent) cells from Pennsylvania State University with a-Si absorber layers made under maximal hydrogen dilution and found a modest increase in hole mobility in these materials compared to conventional a-Si:H. (4) In ``Electroabsorption spectroscopy in solar cells'', researchers discovered and interpreted an infrared absorption band near 1.0 eV, which they believe is caused by dopants and defects at the n/i interface of cells, and which also has interesting implications for the nature of electroabsorption and for the doping mechanism in n-type material.
Date: December 17, 1999
Creator: Schiff, E. A.; Lyou, J.; Kopidakis, N.; Rao, P. & Yuan, Q.
Partner: UNT Libraries Government Documents Department

Non-linear evolution of double tearing modes in tokamaks

Description: The delta prime formalism with neoclassical modifications has proven to be a useful tool in the study of tearing modes in high beta, collisionless plasmas. In this paper the formalism developed for the inclusion of neoclassical effects on tearing modes in monotonic q-profile plasmas is extended to plasmas with hollow current profiles and double rational surfaces. First, the classical formalism of tearing modes in the Rutherford regime in low beta plasmas is extended to q profiles with two rational surfaces. Then it is shown that this formalism is readily extended to include neoclassical effects.
Date: December 17, 1999
Creator: Fredrickson, E.; Bell, M.; Budny, R.V. & Synakowski, E.
Partner: UNT Libraries Government Documents Department

Life-Cycle Cost and Risk Analysis of Alternative Configurations for Shipping Low-Level Radioactive Waste to the Nevada Test Site

Description: The Nevada Test Site (NTS) is a major receiver of low-level radioactive waste (LLW) for disposal. Currently, all LLW received at NTS is shipped by truck. The trucks use highway routes to NTS that pass through the Las Vegas Valley and over Hoover Dam, which is a concern of local stakeholder groups in the State of Nevada. Rail service offers the opportunity to reduce transportation risks and costs, according to the Waste Management Programmatic Environmental Impact Statement (WM-PEIS). However, NTS and some DOE LLW generator sites are not served with direct rail service so intermodal transport is under consideration. Intermodal transport involves transport via two modes, in this case truck and rail, from the generator sites to NTS. LLW shipping containers would be transferred between trucks and railcars at intermodal transfer points near the LLW generator sites, NTS, or both. An Environmental Assessment (EA)for Intermodal Transportation of Low-Level Radioactive Waste to the Nevada Test Site (referred to as the NTSIntermodal -M) has been prepared to determine whether there are environmental impacts to alterations to the current truck routing or use of intermodal facilities within the State of Nevada. However, an analysis of the potential impacts outside the State of Nevada are not addressed in the NTS Intermodal EA. This study examines the rest of the transportation network between LLW generator sites and the NTS and evaluates the costs, risks, and feasibility of integrating intermodal shipments into the LLW transportation system. This study evaluates alternative transportation system configurations for NTS approved and potential generators based on complex-wide LLW load information. Technical judgments relative to the availability of DOE LLW generators to ship from their sites by rail were developed. Public and worker risk and life-cycle cost components are quantified. The study identifies and evaluates alternative scenarios that increase the use of ...
Date: December 17, 1999
Creator: Daling, PM; Ross, SB & Biwer, BM
Partner: UNT Libraries Government Documents Department

Higher Order Lagrange Finite Elements In M3D

Description: The M3D code has been using linear finite elements to represent multilevel MHD on 2-D poloidal planes. Triangular higher order elements, up to third order, are constructed here in order to provide M3D the capability to solve highly anisotropic transport problems. It is found that higher order elements are essential to resolve the thin transition layer characteristic of the anisotropic transport equation, particularly when the strong anisotropic direction is not aligned with one of the Cartesian coordinates. The transition layer is measured by the profile width, which is zero for infinite anisotropy. It is shown that only higher order schemes have the ability to make this layer converge towards zero when the anisotropy gets stronger and stronger. Two cases are considered. One has the strong transport direction partially aligned with one of the element edges, the other doesn't have any alignment. Both cases have the strong transport direction misaligned with the grid line by some angles.
Date: December 17, 2004
Creator: Chen, J.; Strauss, H.R.; Jardin, S.C.; Park, W.; Sugiyama, L.E.; Fu, G. et al.
Partner: UNT Libraries Government Documents Department

Development And Evaluation Of Stable Isotope And Fluorescent Labeling And Detection Methodologies For Tracking Injected Bacteria During In Situ Bioremediation

Description: This report summarizes the results of a research project conducted to develop new methods to label bacterial cells so that they could be tracked and enumerated as they move in the subsurface after they are introduced into the groundwater (i.e., during bioaugmentation). Labeling methods based on stable isotopes of carbon (13C) and vital fluorescent stains were developed. Both approaches proved successful with regards to the ability to effectively label bacterial cells. Several methods for enumeration of fluorescently-labeled cells were developed and validated, including near-real time microplate spectrofluorometry that could be performed in the field. However, the development of a novel enumeration method for the 13C-enriched cells, chemical reaction interface/mass spectrometry (CRIMS), was not successful due to difficulties with the proposed instrumentation. Both labeling methodologies were successfully evaluated and validated during laboratory- and field-scale bacterial transport experiments. The methods developed during this research should be useful for future bacterial transport work as well as other microbial ecology research in a variety of environments. A full bibliography of research articles and meeting presentations related to this project is included (including web links to abstracts and full text reprints).
Date: December 17, 2003
Creator: Fuller, Mark E. & Onstott, Tullis C.
Partner: UNT Libraries Government Documents Department

Interaction of Ambipolar Plasma Flow with Magnetic Islands in a Quasi-axisymmetric Stellarator

Description: A reference equilibrium for the U.S. National Compact Stellarator Experiment is predicted to be sufficiently close to quasi-symmetry to allow the plasma to flow in the toroidal direction with little viscous damping, yet to have sufficiently large deviations from quasi-symmetry that nonambipolarity significantly affects the physics of the shielding of resonant magnetic perturbations by plasma flow. The unperturbed velocity profile is modified by the presence of an ambipolar potential, which broadens the profile and improves the shielding near the plasma edge. In the presence of a resonant magnetic field perturbation, nonambipolar transport produces a radial current, and the resulting jxB force resists departures from the ambipolar velocity and enhances the shielding.
Date: December 17, 2004
Creator: Reiman, A.; Zarnstorff, M.; Mikkelsen, D.; Owen, L.; Mynick, H.; Hudson, S. et al.
Partner: UNT Libraries Government Documents Department

Environmental impacts of proposed Monitored Retrievable Storage

Description: This report describes environmental impacts from a proposed monitored retrievable storage facility for spent fuels to be located in Tennessee. Areas investigated include: water supply, ground water, air quality, solid waste management, and health hazards. (CBS)
Date: December 17, 1985
Partner: UNT Libraries Government Documents Department

An economic analysis of a monitored retrievable storage site for Tennessee

Description: The United States Department of Energy is charged with the task of identifying potential sites for a Monitored Retrievable Storage (MRS) Facility and reporting the results of its analysis to Congress by January 1986. DOE chose three finalist sites from 11 sites DOE analysts evaluated earlier. All three are in Tennessee, including two in Oak Ridge and one in Trousdale/Smith Counties. This paper is a summary of research undertaken on the economic effects of establishing the MRS facility in Tennessee. All three locations were considered in the analysis, but on some occasions attention is focused on the site preferred by DOE. The research was undertaken by the Center for Business and Economic Research (CBER), College of Business Administration, the University of Tennessee, Knoxville, under contract with the Tennessee Department of Economic and Community Development.
Date: December 17, 1985
Creator: Fox, W.F.; Mayo, J.W.; Hansen, L.T. & Quindry, K.E.
Partner: UNT Libraries Government Documents Department

Actinide Sorption in Rainier Mesa Tunnel Waters from the Nevada Test Site

Description: The sorption behavior of americium (Am), plutonium (Pu), neptunium (Np), and uranium (U) in perched Rainier Mesa tunnel water was investigated. Both volcanic zeolitized tuff samples and groundwater samples were collected from Rainier Mesa, Nevada Test Site, NV for a series of batch sorption experiments. Sorption in groundwater with and without the presence of dissolved organic matter (DOM) was investigated. Am(III) and Pu(IV) are more soluble in groundwater that has high concentrations of DOM. The sorption K{sub d} for Am(III) and Pu(IV) on volcanic zeolitized tuff was up to two orders of magnitude lower in samples with high DOM (15 to 19 mg C/L) compared to samples with DOM removed (< 0.4 mg C/L) or samples with naturally low DOM (0.2 mg C/L). In contrast, Np(V) and U(VI) sorption to zeolitized tuff was much less affected by the presence of DOM. The Np(V) and U(VI) sorption Kds were low under all conditions. Importantly, the DOM was not found to significantly sorb to the zeolitized tuff during these experiment. The concentration of DOM in groundwater affects the transport behavior of actinides in the subsurface. The mobility of Am(III) and Pu(IV) is significantly higher in groundwater with elevated levels of DOM resulting in potentially enhanced transport. To accurately model the transport behavior of actinides in groundwater at Rainier Mesa, the low actinide Kd values measured in groundwater with high DOM concentrations must be incorporated in predictive transport models.
Date: December 17, 2007
Creator: Zhao, P.; Zavarin, M.; Leif, R.; Powell, B.; Singleton, M.; Lindvall, R. et al.
Partner: UNT Libraries Government Documents Department

Assessment of Reactivity Margins and Loading Curves for PWR Burnup Credit Cask Designs

Description: This report presents studies to assess reactivity margins and loading curves for pressurized water reactor (PWR) burnup-credit criticality safety evaluations. The studies are based on a generic high-density 32-assembly cask and systematically vary individual calculational (depletion and criticality) assumptions to demonstrate the impact on the predicted effective neutron multiplication factor, k{sub eff}, and burnup-credit loading curves. The purpose of this report is to provide a greater understanding of the importance of input parameter variations and quantify the impact of calculational assumptions on the outcome of a burnup-credit evaluation. This study should provide guidance to regulators and industry on the technical areas where improved information will most enhance the estimation of accurate subcritical margins. Based on these studies, areas where future work may provide the most benefit are identified. The report also includes an evaluation of the degree of burnup credit needed for high-density casks to transport the current spent nuclear fuel inventory. By comparing PWR discharge data to actinide-only based loading curves and determining the number of assemblies that meet the loading criteria, this evaluation finds that additional negative reactivity (through either increased credit for fuel burnup or cask design/utilization modifications) is necessary to accommodate the majority of current spent fuel assemblies in high-capacity casks. Assemblies that are not acceptable for loading in the prototypic high-capacity cask may be stored or transported by other means (e.g., lower capacity casks that utilize flux traps and/or increased fixed poison concentrations or high-capacity casks with design/utilization modifications).
Date: December 17, 2002
Creator: Wagner, J.C.
Partner: UNT Libraries Government Documents Department

Progress Report, December 2010: Improved Site Characterization And Storage Prediction Through Stochastic Inversion Of Time-Lapse Geophysical And Geochemical Data

Description: Over the last project six months, our project activities have concentrated on three areas: (1) performing a stochastic inversion of pattern 16 seismic data to deduce reservoir permeability, (2) development of the geochemical inversion strategy and implementation of associated software, and (3) completing the software implementation of TProGS and the geostatistical analysis that provides the information needed when using the software to produce realizations of the Midale reservoir. The report partially the following deliverables: D2: Model development: MCMC tool (synthetic fluid chemistry data); deliverable completed. D4: Model development/verification: MCMC tool (TProGS, field seismic/chemistry data) work product; deliverable requirements partially fulfilled. D5: Field-based single-pattern simulations work product; deliverable requirements partially fulfilled. When completed, our completed stochastic inversion tool will explicitly integrate reactive transport modeling, facies-based geostatistical methods, and a novel stochastic inversion technique to optimize agreement between observed and predicted storage performance. Such optimization will be accomplished through stepwise refinement of: (1) the reservoir model - principally its permeability magnitude and heterogeneity - and (2) geochemical parameters - primarily key mineral volume fractions and kinetic data. We anticipate that these refinements will facilitate significantly improved history matching and forward modeling of CO{sub 2} storage. Our tool uses the Markov Chain Monte Carlo (MCMC) methodology. Deliverable D1, previously submitted as a report titled ''Development of a Stochastic Inversion Tool To Optimize Agreement Between The Observed And Predicted Seismic Response To CO{sub 2} Injection/Migration in the Weyburn-Midale Project'' (Ramirez et al., 2009), described the stochastic inversion approach that will identify reservoir models that optimize agreement between the observed and predicted seismic response. The software that implements this approach has been completed, tested, and used to process seismic data from pattern 16. A previously submitted report titled ''Model verification: synthetic single pattern simulations using seismic reflection data'', Ramirez et al. 2010, partially fulfilled deliverable ...
Date: December 17, 2010
Creator: Ramirez, A; Mcnab, W; Carle, S; Hao, Y; White, D & Johnson, J
Partner: UNT Libraries Government Documents Department

Modeling of Carbon Tetrachloride Flow and Transport in the Subsurface of the 200 West Disposal Sites: Large-Scale Model Configuration and Prediction of Future Carbon Tetrachloride Distribution Beneath the 216-Z-9 Disposal Site

Description: Three-dimensional simulations considered migration of dense, nonaqueous phase liquid (DNAPL) consisting of CT and co disposed organics in the subsurface as a function of the properties and distribution of subsurface sediments and of the properties and disposal history of the waste. Simulations of CT migration were conducted using the Water-Oil-Air mode of Subsurface Transport Over Multiple Phases (STOMP) simulator. A large-scale model was configured to model CT and waste water discharge from the major CT and waste-water disposal sites.
Date: December 17, 2008
Creator: Oostrom, Mart; Thorne, Paul D.; Zhang, Z. F.; Last, George V. & Truex, Michael J.
Partner: UNT Libraries Government Documents Department

An economic analysis of a monitored retrievable storage site for Tennessee. Final report and appendices

Description: The United States Department of Energy is charged with the task of identifying potential sites for a Monitored Retrievable Storage (MRS) Facility and reporting the results of its analysis to Congress by January 1986. DOE chose three finalist sites from 11 sites DOE analysts evaluated earlier. All three are in Tennessee, including two in Oak Ridge and one in Trousdale/Smith Counties. This paper is a summary of research undertaken on the economic effects of establishing the MRS facility in Tennessee. All three locations were considered in the analysis, but on some occasions attention is focused on the site preferred by DOE. The research was undertaken by the Center for Business and Economic Research (CBER), College of Business Administration, the University of Tennessee, Knoxville, under contract with the Tennessee Department of Economic and Community Development.
Date: December 17, 1985
Creator: Fox, W. F.; Mayo, J. W.; Hansen, L. T. & Quindry, K. E.
Partner: UNT Libraries Government Documents Department

Life-Cycle Cost and Risk Analysis of Alternative Configurations for Shipping Low-Level Radioactive Waste to the Nevada Test Site

Description: This study evaluates alternative transportation system configurations for NTS approved and potential generators based on complex-wide LLW load information. Technical judgments relative to the availability of DOE LLW generators to ship from their sites by rail were developed. Public and worker risk and life-cycle cost components are quantified. The study identifies and evaluates alternative scenarios that increase the use of rail (intermodal where needed) to transport LLW from generator sites to NTS.
Date: December 17, 1999
Creator: Daling, Philip M.; Ross, Steven B. & Biwer, Bruce
Partner: UNT Libraries Government Documents Department

Environmental impacts of proposed Monitored Retrievable Storage. Final report

Description: This report describes environmental impacts from a proposed monitored retrievable storage facility for spent fuels to be located in Tennessee. Areas investigated include: water supply, ground water, air quality, solid waste management, and health hazards. (CBS)
Date: December 17, 1985
Partner: UNT Libraries Government Documents Department

Site-Scale Saturated Zone Flow Model

Description: The purpose of this model report is to document the components of the site-scale saturated-zone flow model at Yucca Mountain, Nevada, in accordance with administrative procedure (AP)-SIII.lOQ, ''Models''. This report provides validation and confidence in the flow model that was developed for site recommendation (SR) and will be used to provide flow fields in support of the Total Systems Performance Assessment (TSPA) for the License Application. The output from this report provides the flow model used in the ''Site-Scale Saturated Zone Transport'', MDL-NBS-HS-000010 Rev 01 (BSC 2003 [162419]). The Site-Scale Saturated Zone Transport model then provides output to the SZ Transport Abstraction Model (BSC 2003 [164870]). In particular, the output from the SZ site-scale flow model is used to simulate the groundwater flow pathways and radionuclide transport to the accessible environment for use in the TSPA calculations. Since the development and calibration of the saturated-zone flow model, more data have been gathered for use in model validation and confidence building, including new water-level data from Nye County wells, single- and multiple-well hydraulic testing data, and new hydrochemistry data. In addition, a new hydrogeologic framework model (HFM), which incorporates Nye County wells lithology, also provides geologic data for corroboration and confidence in the flow model. The intended use of this work is to provide a flow model that generates flow fields to simulate radionuclide transport in saturated porous rock and alluvium under natural or forced gradient flow conditions. The flow model simulations are completed using the three-dimensional (3-D), finite-element, flow, heat, and transport computer code, FEHM Version (V) 2.20 (software tracking number (STN): 10086-2.20-00; LANL 2003 [161725]). Concurrently, process-level transport model and methodology for calculating radionuclide transport in the saturated zone at Yucca Mountain using FEHM V 2.20 are being carried out in the model report, ''Site-Scale Saturated Zone Transport'', MDL-NBS-HS-000010 ...
Date: December 17, 2003
Creator: Zyvoloski, G.
Partner: UNT Libraries Government Documents Department