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A database for compliance with land disposal restrictions

Description: The new restrictions on land disposal introduce additional challenges to hazardous waste managers. Laboratory waste streams consisting of small volumes of diverse waste types will be particularly difficult to manage due to the large number of possible treatment standards that could be applied. To help remedy this management problem, a user-friendly database has been developed to provide the regulatory information required for each of the hazardous wastes present in the wastes stream of a large research laboratory. 3 figs., 1 tab.
Date: September 1, 1990
Creator: McCoy, M.W.
Partner: UNT Libraries Government Documents Department

Resonance localization in tokamaks excited with ICRF waves

Description: Advanced wave models used to evaluate ICRH in tokamaks typically use warm plasma theory and allow inhomogeneity in one dimension. The majority of these calculations neglect the fact that gyrocenters experience the inhomogeneity via their motion parallel to the magnetic field. The non-local effects of rotational transform and toroidicity can play a significant role in both the propagation and the absorption physics. In strongly driven systems, wave damping can distort the particle distribution function supporting the wave and this produces changes in the absorption. The most common approach is to use Maxwellian absorption rates. We have developed a bounce-averaged Fokker-Planck quasilinear computational model which evolves the population of particles on more realistic orbits. Each wave-particle resonance has its own specific interaction amplitude within any given volume element; these data need only be generated once, and appropriately stored for efficient retrieval. The wave-particle resonant interaction then serves as a mechanism by which the diffusion of particle populations can proceed among neighboring orbits. The local specific spectral energy absorption rate is directly calculable once the orbit geometry and populations are determined. The code is constructed in such fashion as to accommodate wave propagation models which provide the wave spectral energy density on a poloidal cross-section. Information provided by the calculation includes the local absorption properties of the medium which can then be exploited to evolve the wave field.
Date: June 20, 1985
Creator: Kerbel, G.D. & McCoy, M.G.
Partner: UNT Libraries Government Documents Department

Kinetic theory and simulation of multi-species plasmas in tokamaks excited with ICRF microwaves

Description: This paper presents a description of a bounce-averaged Fokker-Planck quasilinear model for the kinetic description of tokamak plasmas. The non-linear collision and quasilinear resonant diffusion operators are represented in a form conducive to numerical solution with specific attention to the treatment of the boundary layer separating trapped and passing orbit regions of velocity space. The numerical techniques employed are detailed in so far as they constitute significant departure from those used in the conventional uniform magnetic field case. Examples are given to illustrate the combined effects of collisional and resonant diffusion.
Date: December 21, 1984
Creator: Kerbel, G.D. & McCoy, M.G.
Partner: UNT Libraries Government Documents Department

Collision broadened resonance localization in tokamaks excited with ICRF waves

Description: Advanced wave models used to evaluate ICRH in tokamaks typically use warm plasma theory and allow inhomogeneity in one dimension. The authors have developed a bounce-averaged Fokker-Planck quasilinear computational model which evolves the population of particles on more realistic orbits. Each wave-particle resonance has its own specific interaction amplitude within any given volume element. These data need only be generated once, and appropriately stored for efficient retrieval. The wave-particle resonant interaction then serves as a mechanism by which the diffusion of particle populations can proceed among neighboring orbits. Collisions affect the absorption of rf energy by two quite distinct processes: In addition to the usual relaxation towards the Maxwellian distribution creating velocity gradients which drive quasilinear diffusion, collisions also affect the wave-particle resonance through the mechanism of gyro-phase diffusion. The local specific spectral energy absorption rate is directly calculable once the orbit geometry and populations are determined. The code is constructed in such fashion as to accommodate wave propagation models which provide the wave spectral energy density on a poloidal cross-section. Information provided by the calculation includes the local absorption properties of the medium which can then be exploited to evolve the wave field.
Date: August 1, 1985
Creator: Kerbel, G.D. & McCoy, M.G.
Partner: UNT Libraries Government Documents Department

Cost-benefits of a mobile, trailer-contained, vibratory finishing decontamination facility

Description: The objective of this study was to determine the cost-benefits of a vibratory finishing process, developed at Pacific Northwest Laboratory (PNL), which has been used successfully to remove a variety of transuranic (TRU) contaminants from surfaces of metallic and nonmetallic wastes. Once TRU contaminants are removed, the metallic and nonmetallic materials can be disposed of as low-level waste (LLW). Otherwise, these materials would be disposed of in geologic repositories. This study provides an economic evaluation of the vibratory finishing process as a possible method for use in decontaminating and decommissioning retired facilities at Hanford and oher sites. Specifically, the economic evaluation focuses on a scoping design for a mobile, trailer-contained facility, which could be used in the field in conjunction with decontamination and decommissioning operations. The capital cost of the mobile facility is estimated to be about $1.09 million including contingency and working capital. Annual operating costs, including disposal costs, are estimated to be $440,000 for processing about 6340 ft/sup 3//yr of pre-sectioned, TRU-contaminated material. Combining the operating cost and the capital cost, annualized at a discount rate of 10%, the total annual cost estimate is $602,000. The unit cost for vibratory finishing is estimated to be about $11/ft/sup 3/ of original reference glove box volume (Abrams et at. 1980). All costs are in first quarter 1981 dollars. Although not directly comparable, the unit cost for the vibratory finishing process is very favorable when considered beside typical, substantially higher, unit costs for processing and geologically disposing of TUR-contaminated materials. The probable accuracy of this study cost estimate is about +- 30%. It is therefore recommended that a detailed cost estimate be prepared if a mobile facility is designed.
Date: July 1, 1982
Creator: Hazelton, R.F. & McCoy, M.W.
Partner: UNT Libraries Government Documents Department

Effects of anomalous transport on lower hybrid electron heating

Description: The transport of electron energy out of tokamaks is known to be far greater than that calculated using classical and neoclassical theory. However, low levels of non-axisymmetric magnetic field turbulence can couple the fast transport of electrons parallel to the magnetic field lines to radial transport, thus providing a plausible explanation for observed energy confinement. These models further predict that the electron loss rate is proportional to v/sub parallel bars/. This has subsequently been found to be consistent with data for runaway electrons in PLT, at energies up to 1 MeV. Recently it has been pointed out by Chan, Chiu and Ohkawa that anomalous transport processes should be taken into account in attempting to determine steady state electron distribution functions for cases involving RF electron tail heating, particularly in view of the v/sub parallel bars/ dependence of the loss rate. In this work these physical processes are modeled through a 2-D nonlinear program which describes the evolution of the electron distribution function in velocity magnitude; (v) and plasma radius (r), and which studies the efficiency of tail electron heating.
Date: February 1, 1981
Creator: McCoy, M.G. & Harvey, R.W.
Partner: UNT Libraries Government Documents Department

2005 White Paper on Institutional Capability Computing Requirements

Description: This paper documents the need for a significant increase in the computing infrastructure provided to scientists working in the unclassified domains at Lawrence Livermore National Laboratory (LLNL). This need could be viewed as the next step in a broad strategy outlined in the January 2002 White Paper (UCRL-ID-147449) that bears essentially the same name as this document. Therein we wrote: 'This proposed increase could be viewed as a step in a broader strategy linking hardware evolution to applications development that would take LLNL unclassified computational science to a position of distinction if not preeminence by 2006.' This position of distinction has certainly been achieved. This paper provides a strategy for sustaining this success but will diverge from its 2002 predecessor in that it will: (1) Amplify the scientific and external success LLNL has enjoyed because of the investments made in 2002 (MCR, 11 TF) and 2004 (Thunder, 23 TF). (2) Describe in detail the nature of additional investments that are important to meet both the institutional objectives of advanced capability for breakthrough science and the scientists clearly stated request for adequate capacity and more rapid access to moderate-sized resources. (3) Put these requirements in the context of an overall strategy for simulation science and external collaboration. While our strategy for Multiprogrammatic and Institutional Computing (M&IC) has worked well, three challenges must be addressed to assure and enhance our position. The first is that while we now have over 50 important classified and unclassified simulation codes available for use by our computational scientists, we find ourselves coping with high demand for access and long queue wait times. This point was driven home in the 2005 Institutional Computing Executive Group (ICEG) 'Report Card' to the Deputy Director for Science and Technology (DDST) Office and Computation Directorate management. The second challenge is related ...
Date: January 20, 2006
Creator: Carnes, B; McCoy, M & Seager, M
Partner: UNT Libraries Government Documents Department

PROGRESS REPORT ON FRICTION LOSS OF SLURRIES IN STRAIGHT TUBES

Description: Work on the evaluation of the head loss of slurries flowing in horizontal and vertical tubes is summarized. The slurries used in the investigation were spherical glass beads and lon-exchange resin particles suspended in water. The tube size used was approximately 0.3-in. in inside diameter. Concentrations from zero to approximately 50 wt.% were used. The results are presented in graphical form as head loss in feet of mixture vs. Froude number and a "Z-factor" vs. Froude number. The Z-factor is evaluated as the ratio of the pressure drop of the pure fluid to the pressure drop of the mixture flowing at the same mean velocity. The relation between the Z-factor for turbulent flow and concentration is presented in graphical form for the three directions of flow. (auth)
Date: September 1, 1960
Creator: Murphy, G.; McCoy, M.A. & Wolfe, H.E.
Partner: UNT Libraries Government Documents Department

Three-dimensional simulations of electron cyclotron heating

Description: Many heating problems in tokamaks are inherently three dimensional, involving the velocity coordinates parallel and perpendicular to the ambient magnetic field and the plasma radial coordinate. We will describe a new three-dimensional, Fokker-Planck/rf quasilinear code. This code is based upon a two-dimensional in velocity space Fokker-Planck code which solves for the distribution evaluated at the outer equatorial plane (theta = 0) of each flux surface in a radial mesh.
Date: August 1, 1985
Creator: McCoy, M.G.; Kerbel, G.D. & Harvey, R.W.
Partner: UNT Libraries Government Documents Department

Vibratory finishing as a decontamination process

Description: The major objective of this research is to develop vibratory finishing into a large-scale decontamination technique that can economicaly remove transuranic and other surface contamination from large volumes of waste produced by the operation and decommissioning of retired nuclear facilities. The successful development and widespread application of this decontamination technique would substantially reduce the volume of waste requiring expensive geologic disposal. Other benefits include exposure reduction for decontamination personnel and reduced risk of environmental contamination. Laboratory-scale studies showed that vibratory finishing can rapidly reduce the contamination level of transuranic-contaminated stainless steel and Plexiglas to well below the 10-nCi/g limit. The capability of vibratory finishing as a decontamination process was demonstrated on a large scale. The first decontamination demonstration was conducted at the Hanford N-Reactor, where a vibratory finisher was installed to reduce personnel exposure during the summer outage. Items decontaminated included fuel spacers, process-tube end caps, process-tube inserts, pump parts, ball-channel inspection tools and miscellaneous hand tools. A second demonstration is currently being conducted in the decontamination facility at the Hanford 231-Z Building. During this demonstration, transuranic-contaminated material from decommissioned plutonium facilities is being decontaminated to <10 nCi/g to minimize the volume of material that will require geologic disposal. Items that are being decontaminated include entire glove boxes, process-hood structural material and panels, process tanks, process-tank shields, pumps, valves and hand tools used during the decommissioning work.
Date: October 1, 1980
Creator: McCoy, M.W.; Arrowsmith, H.W. & Allen, R.P.
Partner: UNT Libraries Government Documents Department

Vectorized Fokker-Planck package for the CRAY-1

Description: A program for the solution of the time-dependent, two dimensional, nonlinear, multi-species Fokker-Planck equation is described. The programming is written such that the loop structure is highly vectorizable on the CRAY FORTRAN Compiler. A brief discussion of the Fokker-Planck equation itself is followed by a description of the procedure developed to solve the equation efficiently. The Fokker-Planck equation is a second order partial differential equation whose coefficients depend upon moments of the distribution functions. Both the procedure for the calculation of these coefficients and the procedure for the time advancement of the equation itself must be done efficiently if significant overall time saving is to result. The coefficients are calculated in a series of nested loops, while time advancement is accomplished by a choice of either a splitting or an ADI technique. Overall, timing tests show that the vectorized CRAY program realizes up to a factor of 12 advantage over an optimized CDC-7600 program and up to a factor of 365 over a non-vectorized version of the same program on the CRAY.
Date: August 1, 1979
Creator: McCoy, M.G.; Mirin, A.A. & Killeen, J.
Partner: UNT Libraries Government Documents Department

Fokker-Planck/Transport model for neutral beam driven tokamaks

Description: The application of nonlinear Fokker-Planck models to the study of beam-driven plasmas is briefly reviewed. This evolution of models has led to a Fokker-Planck/Transport (FPT) model for neutral-beam-driven Tokamaks, which is described in detail. The FPT code has been applied to the PLT, PDX, and TFTR Tokamaks, and some representative results are presented.
Date: January 1, 1980
Creator: Killeen, J.; Mirin, A.A. & McCoy, M.G.
Partner: UNT Libraries Government Documents Department

FPPAC: a two-dimensional multispecies nonlinear Fokker-Planck package

Description: The complete nonlinear multispecies Fokker-Planck collision operator for a plasma in two-dimensional velocity space is solved. The operator is expressed in terms of spherical coordinates (v = speed, theta = angle between velocity and magnetic field directions, phi = azimuthal angle) under the assumption of azimuthal symmetry. Provision is made for additional physics contributions.
Date: March 1, 1981
Creator: McCoy, M. G.; Mirin, A. A. & Killeen, J.
Partner: UNT Libraries Government Documents Department

Advanced Simulation and Computing Fiscal Year 2011-2012 Implementation Plan, Revision 0

Description: The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the surety and reliability of the U.S. nuclear stockpile. The SSP uses past nuclear test data along with current and future non-nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering (D&amp;E) programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of current facilities and programs along with new experimental facilities and computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC) is a cornerstone of the SSP, providing simulation capabilities and computational resources to support the annual stockpile assessment and certification, to study advanced nuclear weapons design and manufacturing processes, to analyze accident scenarios and weapons aging, and to provide the tools to enable stockpile Life Extension Programs (LEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balanced resource, including technical staff, hardware, simulation software, and computer science solutions. In its first decade, the ASC strategy focused on demonstrating simulation capabilities of unprecedented scale in three spatial dimensions. In its second decade, ASC is focused on increasing its predictive capabilities in a three-dimensional (3D) simulation environment while maintaining support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (focused on sufficient resolution, dimensionality and scientific details); to quantify critical margins and uncertainties (QMU); and to resolve increasingly difficult analyses needed for the SSP. Moreover, ASC has restructured its business model from one that was very successful in delivering an initial capability to one that is integrated and focused on requirements-driven products that address long-standing technical questions related to enhanced predictive capability in the simulation tools. ...
Date: April 22, 2010
Creator: McCoy, M; Phillips, J; Hpson, J & Meisner, R
Partner: UNT Libraries Government Documents Department

Advanced Simulation and Computing FY07-08 Implementation Plan Volume 2

Description: The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the safety and reliability of the U.S. nuclear stockpile. The SSP uses past nuclear test data along with current and future nonnuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program will require the continued use of current facilities and programs along with new experimental facilities and computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC) is a cornerstone of the SSP, providing simulation capabilities and computational resources to support the annual stockpile assessment and certification, to study advanced nuclear-weapons design and manufacturing processes, to analyze accident scenarios and weapons aging, and to provide the tools to enable Stockpile Life Extension Programs (SLEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balanced resource, including technical staff, hardware, simulation software, and computer science solutions. In its first decade, the ASC strategy focused on demonstrating simulation capabilities of unprecedented scale in three spatial dimensions. In its second decade, ASC is focused on increasing its predictive capabilities in a three-dimensional simulation environment while maintaining the support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (focused on sufficient resolution, dimensionality and scientific details); to quantify critical margins and uncertainties (QMU); and to resolve increasingly difficult analyses needed for the SSP. Moreover, ASC has restructured its business model from one that was very successful in delivering an initial capability to one that is integrated and focused on requirements-driven products that address long-standing technical questions related to enhanced predictive capability in the simulation tools. ASC ...
Date: June 22, 2006
Creator: Kusnezov, D; Hale, A; McCoy, M & Hopson, J
Partner: UNT Libraries Government Documents Department

Advanced Simulation and Computing FY08-09 Implementation Plan Volume 2 Revision 0

Description: The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the safety and reliability of the U.S. nuclear stockpile. The SSP uses past nuclear test data along with current and future nonnuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of current facilities and programs along with new experimental facilities and computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC) is a cornerstone of the SSP, providing simulation capabilities and computational resources to support the annual stockpile assessment and certification, to study advanced nuclear-weapons design and manufacturing processes, to analyze accident scenarios and weapons aging, and to provide the tools to enable Stockpile Life Extension Programs (SLEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balanced resource, including technical staff, hardware, simulation software, and computer science solutions. In its first decade, the ASC strategy focused on demonstrating simulation capabilities of unprecedented scale in three spatial dimensions. In its second decade, ASC is focused on increasing its predictive capabilities in a three-dimensional simulation environment while maintaining the support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (focused on sufficient resolution, dimensionality and scientific details); to quantify critical margins and uncertainties (QMU); and to resolve increasingly difficult analyses needed for the SSP. Moreover, ASC has restructured its business model from one that was very successful in delivering an initial capability to one that is integrated and focused on requirements driven products that address long-standing technical questions related to enhanced predictive capability in the simulation tools. ASC ...
Date: April 25, 2007
Creator: McCoy, M; Kusnezov, D; Bikkel, T & Hopson, J
Partner: UNT Libraries Government Documents Department

Advanced Simulation and Computing FY08-09 Implementation Plan, Volume 2, Revision 0.5

Description: The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the surety and reliability of the U.S. nuclear stockpile. The SSP uses past nuclear test data along with current and future non-nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of current facilities and programs along with new experimental facilities and computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC)1 is a cornerstone of the SSP, providing simulation capabilities and computational resources to support the annual stockpile assessment and certification, to study advanced nuclear-weapons design and manufacturing processes, to analyze accident scenarios and weapons aging, and to provide the tools to enable Stockpile Life Extension Programs (SLEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balanced resource, including technical staff, hardware, simulation software, and computer science solutions. In its first decade, the ASC strategy focused on demonstrating simulation capabilities of unprecedented scale in three spatial dimensions. In its second decade, ASC is focused on increasing its predictive capabilities in a three-dimensional simulation environment while maintaining the support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (focused on sufficient resolution, dimensionality and scientific details); to quantify critical margins and uncertainties (QMU); and to resolve increasingly difficult analyses needed for the SSP. Moreover, ASC has restructured its business model from one that was very successful in delivering an initial capability to one that is integrated and focused on requirements-driven products that address long-standing technical questions related to enhanced predictive capability in the simulation tools. ASC must ...
Date: September 13, 2007
Creator: Kusnezov, D; Bickel, T; McCoy, M & Hopson, J
Partner: UNT Libraries Government Documents Department

Advanced Simulation and Computing FY10-FY11 Implementation Plan Volume 2, Rev. 0.5

Description: The Stockpile Stewardship Program (SSP) is a single, highly integrated technical program for maintaining the surety and reliability of the U.S. nuclear stockpile. The SSP uses past nuclear test data along with current and future non-nuclear test data, computational modeling and simulation, and experimental facilities to advance understanding of nuclear weapons. It includes stockpile surveillance, experimental research, development and engineering (D&amp;E) programs, and an appropriately scaled production capability to support stockpile requirements. This integrated national program requires the continued use of current facilities and programs along with new experimental facilities and computational enhancements to support these programs. The Advanced Simulation and Computing Program (ASC) is a cornerstone of the SSP, providing simulation capabilities and computational resources to support the annual stockpile assessment and certification, to study advanced nuclear weapons design and manufacturing processes, to analyze accident scenarios and weapons aging, and to provide the tools to enable stockpile Life Extension Programs (LEPs) and the resolution of Significant Finding Investigations (SFIs). This requires a balanced resource, including technical staff, hardware, simulation software, and computer science solutions. In its first decade, the ASC strategy focused on demonstrating simulation capabilities of unprecedented scale in three spatial dimensions. In its second decade, ASC is focused on increasing its predictive capabilities in a three-dimensional (3D) simulation environment while maintaining support to the SSP. The program continues to improve its unique tools for solving progressively more difficult stockpile problems (focused on sufficient resolution, dimensionality and scientific details); to quantify critical margins and uncertainties (QMU); and to resolve increasingly difficult analyses needed for the SSP. Moreover, ASC has restructured its business model from one that was very successful in delivering an initial capability to one that is integrated and focused on requirements-driven products that address long-standing technical questions related to enhanced predictive capability in the simulation tools. ...
Date: September 8, 2009
Creator: Meisner, R; Peery, J; McCoy, M & Hopson, J
Partner: UNT Libraries Government Documents Department

Computer models for kinetic equations of magnetically confined plasmas

Description: This paper presents four working computer models developed by the computational physics group of the National Magnetic Fusion Energy Computer Center. All of the models employ a kinetic description of plasma species. Three of the models are collisional, i.e., they include the solution of the Fokker-Planck equation in velocity space. The fourth model is collisionless and treats the plasma ions by a fully three-dimensional particle-in-cell method.
Date: January 1, 1987
Creator: Killeen, J.; Kerbel, G.D.; McCoy, M.G.; Mirin, A.A.; Horowitz, E.J. & Shumaker, D.E.
Partner: UNT Libraries Government Documents Department