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Portable implementation of implicit methods for the UEDGE and BOUT codes on parallel computers

Description: A description is given of the parallelization algorithms and results for two codes used ex- tensively to model edge-plasmas in magnetic fusion energy devices. The codes are UEDGE, which calculates two-dimensional plasma and neutral gas profiles, and BOUT, which cal- culates three-dimensional plasma turbulence using experimental or UEDGE profiles. Both codes describe the plasma behavior using fluid equations. A domain decomposition model is used for parallelization by dividing the global spatial simulation region into a set of domains. This approach allows the used of two recently developed LLNL Newton-Krylov numerical solvers, PVODE and KINSOL. Results show an order of magnitude speed up in execution time for the plasma equations with UEDGE. A problem which is identified for UEDGE is the solution of the fluid gas equations on a highly anisotropic mesh. The speed up of BOUT is closer to two orders of magnitude, especially if one includes the initial improvement from switching to the fully implicit Newton-Krylov solver. The turbulent transport coefficients obtained from BOUT guide the use of anomalous transport models within UEDGE, with the eventual goal of a self-consistent coupling.
Date: February 17, 1999
Creator: Rognlien, T D & Xu, X Q
Partner: UNT Libraries Government Documents Department

BPERM version 3.0: A 2-D wakepotential/impedance code

Description: BPERM 3.0 is an improved version of a previous release. The main purpose of this version is to make it more user friendly. Following a simple 1-2-3 procedure, one obtains both text and graphical output of the wakepotential and impedance for a given geometry. The calculation is based on a boundary perturbation method, which is significantly faster than numerical simulations. It is accurate when the discontinuities are small. In particular, it works well for tapered structures. 5 refs., 3 figs.
Date: October 1, 1996
Creator: Barts, T. & Chou, W.
Partner: UNT Libraries Government Documents Department

Basis of Estimate Software Tool (BEST) - a practical solution to part of the cost and schedule integration puzzle

Description: The Basis of Estimate Software Tool (BEST) was developed at the Rocky Flats Environmental Technology Site (Rocky Flats) to bridge the gap that exists in conventional project control systems between scheduled activities, their allocated or assigned resources, and the set of assumptions (basis of estimate) that correlate resources and activities. Having a documented and auditable basis of estimate (BOE) is necessary for budget validation, work scope analysis, change control, and a number of related management control functions. The uniqueness of BEST is demonstrated by the manner in which it responds to the diverse needs of the heavily regulated environmental workplace - containing many features not found in conventional off-the-shelf software products. However, even companies dealing in relatively unregulated work places will find many attractive features in BEST. This product will be of particular interest to current Government contractors and contractors preparing proposals that may require subsequent validation. 2 figs.
Date: February 1, 1997
Creator: Murphy, L. & Bain, P.
Partner: UNT Libraries Government Documents Department

Reservoir characterization and performance predictions for the E.N. Woods lease

Description: The task of this work was to evaluate the past performance of the E.N. WOODS Unit and to forecast its future economic performance by taking into consideration the geology, petrophysics and production history of the reservoir. The Decline Curve Analysis feature of the Appraisal of Petroleum Properties including Taxation Systems (EDAPT) software along with the Production Management Systems (PMS) software were used to evaluate the original volume of hydrocarbon in place and estimate the reserve. The Black Oil Simulator (BOAST II) was then used to model the waterflooding operation and estimate the incremental oil production attributable to the water injection. BOAST II was also used to predict future performance of the reservoir.
Date: July 7, 2000
Creator: Aka-Milan, Francis A.
Partner: UNT Libraries Government Documents Department

BALTRIM v.1

Description: BalTrim is an Excel(R) spreadsheet designed to calculate the inertial mass properties and ballast trim weight for either an assembled reentry vehicle (RV) or reentry body (RB). With this application, the user enters known mass properties and global coordinates for each subcomponent of the assembly, and BalTrim calculates the mass properties of the total assembly. Then, using the assembly mass properties, BalTrim calculates the necessary amount of ballast trim weight required to dynamically and statically balance the assembly mass properties. The final mass properties and trim ballast weight calculated with BalTrim agree with physicaly measured values.
Date: February 1, 1999
Creator: Gaffney, Thomas M.
Partner: UNT Libraries Government Documents Department

Users manual for bfort: Producing Fortran interfaces to C source code

Description: In many applications, the most natural computer language to write in may be different from the most natural language to provide a library in. For example, many scientific computing applications are written in Fortran, while many software libraries-particularly those dealing with complicated data structures or dynamic memory management-are written in C. Providing an interface so that Fortran programs can call routines written in C can be a tedious and error-prone process. We describe here a tool that automatically generates a Fortran-callable wrapper for routines written in C, using only a small, structured comment and the declaration of the routine in C. This tool has been used on two large software packages, PETSc and the MPICH implementation of MPI.
Date: March 1, 1995
Creator: Gropp, W.
Partner: UNT Libraries Government Documents Department

Modeling of Localized Neutral Particle Sources in 3D Edge Plasmas

Description: A new edge plasma code BoRiS [1] has a fully 3D fluid plasma model. We supplement BoRiS with a 3D fluid neutral model including equations for parallel momentum and collisional perpendicular diffusion. This makes BoRiS an integrated plasma-neutral model suitable for a variety of applications. We present modeling results for a localized gas source in the geometry of the NCSX stellarator.
Date: May 23, 2002
Creator: Umansky, M V; Rognlien, T D; Fenstermacher, M E; Borchardt, M; Mutzke, A; Riemann, J et al.
Partner: UNT Libraries Government Documents Department

On the Performance of Parallel Algebraic Multigrid

Description: As algebraic multigrid (AMG) can be applied to a wide variety of problems on extremely large, unstructured grids on the one hand and massively parallel computer systems are available on the other hand, there has been a need for parallel implementations of AMG. This report analyses the performance of BoomerAMG[1], a parallel algorithm developed at Lawrence Livermore National Laboratory. Abstracting the implementation we describe the basic components of the costly setup phase and analyze their behavior in a (massively) parallel distributed memory environment. We present numerical results, compare them to the developed theory and finally aim at possible improvements in the future.
Date: February 18, 2003
Creator: Naegel, Arne & Falgout, Robert
Partner: UNT Libraries Government Documents Department

Electroforming cell design tool development

Description: The Electroforming Advisor (EFA) team has developed a prototype of an EFA, an easy-to-use design and computational problem solving environment for Electroforming. A primary goal is to enable electroformers to optimally design a cell that would make a part right the first time and with minimum cost. Computer simulations can be carried out much faster than experimentation and without hazardous waste production. The EFA prototype uses the Computer-Aided Design (CAD) and the Computer-Aided Engineering (CAE) capabilities of the Intergraph Engineering Modeling System coupled with the simulation capabilities of a locally developed three-dimensional boundary element code, BEPLATE. 1 ref., 7 figs.
Date: April 1, 1996
Creator: Giles, G.E.
Partner: UNT Libraries Government Documents Department

Turbulences in boundary plasmas

Description: We simulate boundary plasma turbulence using a 3D turbulence code BOUT and a linearized electromagnetic instability shooting code BAL. The code BOUT solves fluid equations for plasma vorticity,density, ion temperature and parallel momentum (along the magnetic field), electron temperature, and parallel momentum. A realistic DIII-D X point magnetic geometry is used. The focus is on the possible local linear instability drivers and turbulence suppression mechanisms from L to H mode. Comparison is made with data from the DIII-D toltamak where probe measurements provide turbulence statistics in the boundary plasma and transport modeling.
Date: May 15, 1998
Creator: Xu, X. Q., LLNL
Partner: UNT Libraries Government Documents Department

Volume 4: Characterization of representative reservoirs -- Gulf of Mexico field, U-8 reservoir

Description: A reservoir study was performed using a publicly available black oil simulator to history match and predict the performance of a Gulf of Mexico reservoir. The first objective of this simulation study was to validate the Black Oil Applied Simulation Tool version three for personal computers (BOAST3-PC) model to ensure the integrity of the simulation runs. Once validation was completed, a field history match for the Gulf of Mexico U-8 oil reservoir was attempted. A verbal agreement was reached with the operator of this reservoir to blindcode the name and location of the reservoir. In return, the operator supplied data and assistance in regards to the technical aspects of the research. On the basis of the best history match, different secondary recovery techniques were simulated as a predictive study for enhancing the reservoir productivity.
Date: July 1, 1998
Creator: Koperna, G.J. Jr.; Johnson, H.R.; Salamy, S.P.; Reeves, T.K.; Sawyer, W.K.; Kimbrell, W.C. et al.
Partner: UNT Libraries Government Documents Department

Volume 3: Characterization of representative reservoirs -- South Marsh Island 73, B35K and B65G Reservoirs

Description: This report documents the results of a detailed study of two Gulf of Mexico salt dome related reservoirs and the application of a publicly available PC-based black oil simulator to model the performances of gas injection processes to recover attic oil. The overall objective of the research project is to assess the oil reserve potential that could result from the application of proven technologies to recover bypassed oil from reservoirs surrounding piercement salt domes in the Gulf of Mexico. The specific study objective was to simulate the primary recovery and attic gas injection performance of the two subject reservoirs to: (1) validate the BOAST model; (2) quantify the attic volume; and (3) predict the attic oil recovery potential that could result from additional updip gas injection. The simulation studies were performed on the B-35K Reservoir and the B-65G Reservoir in the South Marsh Island Block 73 Field using data provided by one of the field operators. A modified PC-version of the BOAST II model was used to match the production and injection performances of these reservoirs in which numerous gas injection cycles had been conducted to recover attic oil. The historical performances of the gas injection cycles performed on both the B-35K Reservoir and B-65G Reservoir were accurately matched, and numerous predictive runs were made to define additional potential for attic oil recovery using gas injection. Predictive sensitivities were conducted to examine the impact of gas injection rate, injection volume, post-injection shut-in time, and the staging of gas injection cycles on oil recovery.
Date: July 1, 1998
Creator: Young, M.A.; Salamy, S.P.; Reeves, T.K.; Kimbrell, W.C. & Sawyer, W.K.
Partner: UNT Libraries Government Documents Department

Modeling of the Arctic boundary layer: Comparisons with measurements from the Arctic Ocean Expedition 1996

Description: During the recent 3 month Arctic Ocean Expedition (AOE-96) to the North Pole during the summer of 1996 an enormous amount of data collected on the Arctic planetary boundary layer. In preparation for the expedition, the authors have developed an expanded and quite flexible 1-D computer code based on the successful work of ReVelle and of ReVelle and Coulter on modeling of boundary layer ``bursting``. This new code, BLMARC (Boundary Layer, Mixing, Aerosols, Radiation and Clouds), explicitly includes the physical and chemical effects due to the presence of clouds, aerosols and associated air chemistry. Using data from AOE-96 and the model BLMARC, the authors have begun a systematic effort to compare observations of the high Arctic boundary layer against numerical modeling results. The preliminary results for case963 and case964 are quite promising. The second period exhibits what appears to be bursting effects in the temperature, the winds and in the aerosol concentration and the modeling efforts have shown a similar set of features as well. Current work also includes model experiments with BLMARC on the aerosol nucleation and growth in the Arctic PBL and cloud and fog formation.
Date: August 1, 1997
Creator: ReVelle, D.O.; Nilsson, E.D. & Kulmala, M.
Partner: UNT Libraries Government Documents Department

User News. Volume 17, Number 1 -- Spring 1996

Description: This is a newsletter for users of the DOE-2, PowerDOE, SPARK, and BLAST building energy simulation programs. The topics for the Spring 1996 issue include the SPARK simulation environment, DOE-2 validation, listing of free fenestration software from LBNL, Web sites for building energy efficiency, the heat balance method of calculating building heating and cooling loads.
Date: July 1, 1996
Partner: UNT Libraries Government Documents Department

PROGRESS IN THE PEELING-BALLOONING MODEL OF ELMS: NUMERICAL STUDIES OF 3D NONLINEAR ELM DYNAMICS

Description: Nonlinear simulations with the 3D electromagnetic two-fluid BOUT code are employed to study the dynamics of edge localized modes (ELMs) driven by intermediate wavelength peeling-ballooning modes. It is found that the early behavior of the modes is similar to expectations from linear, ideal peeling-ballooning mode theory, with the modes growing linearly at a fraction of the Alfven frequency. In the nonlinear phase, the modes grow explosively, forming a number of extended filaments which propagate rapidly from the outer closed flux region into the open flux region toward the outboard wall. Similarities to non-linear ballooning theory, as well as additional complexities are observed. Comparison to observations reveals a number of similarities. Implications of the simulations and proposals for the dynamics of the full ELM crash are discussed.
Date: November 1, 2004
Creator: SNYDER,P.B; WILSON,H.R & XU,X.Q
Partner: UNT Libraries Government Documents Department

An MPI version of the BLACS

Description: In this paper, issues related to implementing an MPI version of the Basic Linear Communication Subprograms (BLACS) are investigated. A set of routines, the MPI Linear Algebra Communication Subprograms (MLACS), are presented, and these arc used to implement an MPI version of the BLACS, The MLACS provide the same functionality as the BLACS, but extend the functionality of the BLACS to include both blocking and nonblocking communication, and all four of the MPI communication modes.
Date: October 1994
Creator: Walker, D. W.
Partner: UNT Libraries Government Documents Department

Heavy ion beam transport in an inertial confinement fusion reactor

Description: A new code, bimc, is under development to determine if a beam of heavy ions can be focused to the necessary spot-size radius of about 2 mm within an inertial confinement reactor chamber where the background gas densities are on the order of 10{sup 14}--10{sup 15} cm{sup {minus}3} Lithium (or equivalent). Beam transport is expected to be strongly affected by stripping and collective plasma phenomena; however, if propagation is possible in this regime, it could lead to simplified reactor designs. The beam is modeled using a 2 1/2 D particle-in-cell (PIC) simulation code coupled with a Monte Carlo (MC) method for analyzing collisions. The MC code follows collisions between the beam ions and neutral background gas atoms that account for the generation of electrons and background gas ions (ionization), and an increase of the charge state of the beam ions (stripping). The PIC code models the complete dynamics of the interaction of the various charged particle species with the self generated electromagnetic fields. Details of the code model and preliminary results are presented.
Date: August 1, 1995
Creator: Barboza, N.
Partner: UNT Libraries Government Documents Department