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A description of NUEXS, an upgrade of the code FCUP used to compute proton recoil current from CH{sub 2} foils

Description: A computer code, FCUP, developed by A. Craft computes currents of recoil protons from a time- and energy-dependent neutron flux striking a CH{sub 2} foil. Three problem areas need to be addressed to extend the code`s usefulness. First, FCUP computes a response that is not time dependent; that is, only the input time bin is broadened to account for the finite time distribution of protons from a single neutron energy; second, the time coordinate of the signal predicted is translated arbitrarily rather than absolutely relative to the time of maximum neutron production in the source; and third, the code does not account for electron pickup by protons at low proton energies in the target and absorber foils. This report describes the changes in calculational method used to overcome these problems.
Date: August 1, 1982
Creator: Stelts, M.L. & Wood, B.E.
Partner: UNT Libraries Government Documents Department

FUELPIN: a data retrieval system for nuclear fuel pin information

Description: The Fortran IV computer code FUELPIN was developed to assist in the surveillance of large numbers of nuclear fuel pins. Using sixteen levels of sorting and thirty-one key pin characteristics, the computer code sorts through large blocks of pin data to determine those pins having the desired characteristics. Allowance is also made for miscellaneous information on (1) fuel type, (2) clad material, (3) bond data, and (4) general pin information. Upon execution the blocks of fuel pin information are inspected to insure that the data are credible, i.e., between experimenter specified limits. Octal stops are provided, numbered, and discussed in the codes comment section so as to block all paths of code execution known to indicate operational error. All parameter sort information is also inspected for potential input error with some minor correctional measures accomplished upon detection of an error condition. Though limited to blocks of two hundred and fifty pins per run, large numbers of pins may be efficiently examined through problem stacking and proper use of a built in computer time economizing scheme. (auth)
Date: January 1, 1974
Creator: Walters, K.L.; Barner, J.O. & Green, J.L.
Partner: UNT Libraries Government Documents Department

Progress in mix modeling

Description: We have identified the Cranfill multifluid turbulence model (Cranfill, 1992) as a starting point for development of subgrid models of instability, turbulent and mixing processes. We have differenced the closed system of equations in conservation form, and coded them in the object-oriented hydrodynamics code FLAG, which is to be used as a testbed for such models.
Date: March 14, 1997
Creator: Harrison, A.K.
Partner: UNT Libraries Government Documents Department

Generalization of the FRAM's Bias

Description: The Fixed-Energy Response-Function Analysis with Multiple Efficiency (FRAM) code was developed at Los Alamos National Laboratory to measure the gamma-ray spectrometry of the isotopic composition of plutonium, uranium, and other actinides. Its reported uncertainties of the results come from the propagation of the statistics in the peak areas only. No systematic error components are included in the reported uncertainties. We have done several studies and found that the FRAM's statistical precision can be reasonably represented by its reported uncertainties. The FRAM's biases or systematic uncertainties can come from a variety of sources and can be difficult to determine. We carefully examined the FRAM analytical results of the archival plutonium data and of the data specifically acquired for this isotopic uncertainty analysis project and found the relationship between the bias and other parameters. We worked out the equations representing the biases of the measured isotopes from each measurement using the internal parameters in the spectrum such as peak resolution and shape, region of analysis, and burnup (for plutonium) or enrichment (for uranium).
Date: October 1, 2005
Creator: Vo, Duc T.
Partner: UNT Libraries Government Documents Department

Advanced system identification techniques for wind turbine structures with special emphasis on modal parameters

Description: The goal of this research is to develop advanced system identification techniques that can be used to accurately measure the frequency response functions of a wind-turbine structure immersed in wind noise. To allow for accurate identification, the authors have developed a special test signal called the Pseudo-Random Binary Sequence (PRBS). The Matlab program that generates this signal allows the user to interactively tailor its parameters for the frequency range of interest based on the response of the wind turbine under test. By controlling NREL`s Mobile Hydraulic Shaker System, which is attached to the wind turbine structure, the PRBS signal produces the wide-band excitation necessary to perform system identification in the presence of wind noise. The techniques presented here will enable researchers to obtain modal parameters from an operating wind turbine, including frequencies, damping coefficients, and mode shapes. More importantly, the algorithms they have developed and tested (so far using input-output data from a simulated structure) permit state-space representation of the system under test, particularly the modal state space representation. This is the only system description that reveals the internal behavior the system, such as the interaction between the physical parameters, and which, in contrast to transfer functions, is valid for non-zero initial conditions.
Date: June 1, 1995
Creator: Bialasiewicz, J.T.
Partner: UNT Libraries Government Documents Department

Toroidal Effects on ICRF Heating and Current Drive

Description: Numerical studies, performed with the Monte-Carlo code FIDO [1], of the evolution of the resonant-ion distribution function in the presence of ICRH in toroidal geometry are presented. In particular it is pointed out how the absorption of toroidal momentum from a wave field with finite parallel wave numbers causes spatial drift and diffusion, which together with the finite orbit widths of the tail ions is shown to have a large effect on the temperature profile of the resonant ion species and also to cause losses of high-energy ions to the wall [2]. Furthermore, it is found that the finite orbit width and the inward drift occuring for negative parallel wave numbers [3] each give rise to a new mechanism of minority-ion cyclotron current drive as compared to earlier models where the drift orbits of the resonant ions are confined to the magnetic flux surfaces. For high levels of coupled power these new mechanisms are found to be the dominating ones [4,5].
Date: April 12, 1999
Creator: Carlsson, J.; Hedin, J. & Hellsten, T.
Partner: UNT Libraries Government Documents Department

Experiences with FETI-DP in a Production Level Finite Element Application

Description: We discuss application of the FETI-DP linear solver within the Salinas finite element application. An overview of Salinas and of the FETI-DP solver is presented. We discuss scalability of the software on ASCI-red, Cplant and ASCI-white. Options for solution of the coarse grid problem that results from the FETI problem are evaluated. The finite element software and solver are seen to be numerically and cpu scalable on each of these platforms. In addition, the software is very robust and can be used on a large variety of finite element models.
Date: May 1, 2002
Partner: UNT Libraries Government Documents Department

Moment-Based Probability Modeling and Extreme Response Estimation, The FITS Routine Version 1.2

Description: This report documents the use of the FITS routine, which provides automated fits of various analytical, commonly used probability models from input data. It is intended to complement the previously distributed FITTING routine documented in RMS Report 14 (Winterstein et al., 1994), which implements relatively complex four-moment distribution models whose parameters are fit with numerical optimization routines. Although these four-moment fits can be quite useful and faithful to the observed data, their complexity can make them difficult to automate within standard fitting algorithms. In contrast, FITS provides more robust (lower moment) fits of simpler, more conventional distribution forms. For each database of interest, the routine estimates the distribution of annual maximum response based on the data values and the duration, T, over which they were recorded. To focus on the upper tails of interest, the user can also supply an arbitrary lower-bound threshold, {chi}{sub low}, above which a shifted distribution model--exponential or Weibull--is fit.
Date: November 1, 1999
Partner: UNT Libraries Government Documents Department

LNG Safety Research: FEM3A Model Development

Description: The initial scope of work for this project included: (1) Improving the FEM3A advanced turbulence closure module, (2) Adaptation of FEM3A for more general applications, and (3) Verification of dispersion over rough surfaces, with and without obstacle using the advanced turbulence closure module. These work elements were to be performed by Chemical Hazards Research Center (CHRC), Department of Chemical Engineering, University of Arkansas as a subcontractor to Gas Technology Institute (GTI). The tasks for GTI included establishment of the scientific support base for standardization of the FEM3A model, project management, technology transfer, and project administration. Later in the course of the project, the scope of work was modified by the National Energy Technology Laboratories (NETL) to remove the emphasis on FEM3A model and instead, develop data in support of NETL's FLUENT modeling. With this change, GTI was also instructed to cease activities relative to FEM3A model. GTI's technical activities through this project included the initial verification of FEM3A model, provision of technical inputs to CHRC researchers regarding the structure of the final product, and participation in technical discussion sessions with CHRC and NETL technical staff. GTI also began the development of a Windows-based front end for the model but the work was stopped due to the change in scope of work. In the meantime, GTI organized a workshop on LNG safety in Houston, Texas. The workshop was very successful and 75 people from various industries participated. All technical objectives were met satisfactorily by Dr. Jerry Havens and Dr. Tom Spicer of CHRC and results are presented in a stand-alone report included as Appendix A to this report.
Date: September 30, 2006
Creator: Salehi, Iraj A.; Havens, Jerry & Spicer, Tom
Partner: UNT Libraries Government Documents Department

LNG Safety Research: FEM3A Model Development

Description: During this reporting period, kickoff and planning meetings were held. Subcontracted experimental and modeling tasks were defined. Efforts to address the numerical stability problems that hamper FEM3A's applicability to low wind speed, stable atmospheric conditions were initiated. A detailed review of FEM3A code and its execution, required for development of an accessible user interface, was also begun. A one-day workshop on LNG safety models has been scheduled for September 2004. The goals of this project are to develop a national focal point for LNG safety research and technical dissemination and to develop the FEM3A dispersion model for application to general scenarios involving dispersion problems with obstacle and terrain features of realistic complexity. During this reporting period, the objectives and scope of the project and its constituent tasks were discussed at a project kickoff meeting in Morgantown. Details of the subcontracted experimental and modeling tasks were further defined at a separate meeting at the University of Arkansas. Researchers at the university have begun to modify the turbulence closure model used in FEM3A to insure numerical stability during simulation of low-wind-speed, stable atmospheric conditions. The university's wind tunnel is being prepared for upcoming experimental studies. GTI has begun a detailed review of the FEM3A code and its execution that will provide guidance during development of an accessible user interface. Plans were made for a one day workshop on LNG safety models that will be held at the end of September and will provide an introduction to currently available and pending software tools.
Date: June 30, 2004
Creator: Dallbauman, Liese
Partner: UNT Libraries Government Documents Department

LNG Safety Research: FEM3A Model Development

Description: This quarterly report for DE-FG26-04NT42030 covers a period from July 1, 2004 to September 30, 2004. Activity during this period included preparation of a CD containing the FEM3a FORTRAN code for distribution and organization of an LNG safety workshop. Contract negotiation between GTI and University of Arkansas continued.
Date: September 30, 2004
Creator: Salehi, Iraj A.
Partner: UNT Libraries Government Documents Department

LNG Safety Research: FEM3A Model Development

Description: This quarterly report for DE-FG26-04NT42030 covers a period from July 1, 2006 to October 31, 2006. GTI's activities during the report quarter were limited to administrative work. The work at the University of Arkansas continued in line with the initial scope of work and the identified questions regarding surface to cloud heat transfer as being largely responsible for the instability problems previously encountered. A brief summary of results is discussed in this section and the complete report from University of Arkansas is provided. All work planned for this project has been completed. Specifically: Task A--Simulation of Low-Wind-Speed Stable Atmospheric Conditions: This task has been completed, and a new version of FEM3A will be received by GTI. Task B--Verification for Dispersion over Rough Surfaces With and Without Obstacles: This task has been completed, and a new version of FEM3A will be received by GTI. Task C--Adapting the FEM3A Model for More General Application This task was obviated when DOE redirected the contract near the project midpoint. Task D--Provide assistance and wind tunnel data to DOE for FLUENT development This task has been completed and data requested by DOE-NETL has been delivered. Researchers at the University of Arkansas are preparing the final report that will be received by GTI by November 30, 2006.
Date: September 30, 2006
Creator: Salehi, Iraj A.; Havens, Jerry & Spicer, Tom
Partner: UNT Libraries Government Documents Department

Installation Guide for FEMIS v1.4.6

Description: The FEMIS Installation Guide provides instructions for installing and configuring the FEMIS software package.
Date: June 29, 1999
Creator: Arp, Jonathan A.; Burnett, Robert A.; Carter, Richard J.; Downing, Timothy R.; Dunkle, Julie R.; Fangman, Patricia M. et al.
Partner: UNT Libraries Government Documents Department

Calculation of the small scale self-focusing ripple gain spectrum for the CYCLOPS laser system: a status report

Description: The FLAC code (Fourier Laser Amplifier Code) was used to simulate the CYCLOPS laser system up to the third B-module and to calculate the maximum ripple gain spectrum. The model of this portion of CYCLOPS consists of 33 segments that correspond to 20 optical elements (simulation of the cell requires 2 segments and 12 external air spaces). (MHR)
Date: October 1, 1976
Creator: Fleck, J. A. Jr.; Morris, J. R. & Thompson, P. F.
Partner: UNT Libraries Government Documents Department

FRAMES Software System: Linking to the Statistical Package R

Description: This document provides requirements, design, data-file specifications, test plan, and Quality Assurance/Quality Control protocol for the linkage between the statistical package R and the Framework for Risk Analysis in Multimedia Environmental Systems (FRAMES) Versions 1.x and 2.0. The requirements identify the attributes of the system. The design describes how the system will be structured to meet those requirements. The specification presents the specific modifications to FRAMES to meet the requirements and design. The test plan confirms that the basic functionality listed in the requirements (black box testing) actually functions as designed, and QA/QC confirms that the software meets the client’s needs.
Date: December 11, 2006
Creator: Castleton, Karl J.; Whelan, Gene & Hoopes, Bonnie L.
Partner: UNT Libraries Government Documents Department

Velocimetry signal synthesis with fringen.

Description: An important part of velocimetry analysis is the recovery of a known velocity history from simulated data signals. The fringen program synthesizes VISAR and PDV signals, given a specified velocity history, using exact formulations for the optical signal. Time-dependent light conditions, non-ideal measurement conditions, and various diagnostic limitations (noise, etc.) may be incorporated into the simulated signals. This report describes the fringen program, which performs forward VISAR (Velocity Interferometer System for Any Reflector) and PDV (Photonic Doppler Velocimetry, also known as heterodyne velocimetry) analysis. Nearly all effects that might occur in VISAR/PDV measurement of a single velocity can be modeled by fringen. The program operates in MATLAB, either within a graphical interface or as a user-callable function. The current stable version of fringen is 0.3, which was released in October 2010. The following sections describe the operation and use of fringen. Section 2 gives a brief overview of VISAR and PDV synthesis. Section 3 illustrates the graphical and console interface of fringen. Section 4 presents several example uses of the program. Section 5 summarizes program capabilities and discusses potential future work.
Date: February 1, 2011
Creator: Dolan, Daniel H., III
Partner: UNT Libraries Government Documents Department

Automated mask creation from a 3D model using Faethm.

Description: We have developed and implemented a method which given a three-dimensional object can infer from topology the two-dimensional masks needed to produce that object with surface micro-machining. The masks produced by this design tool can be generic, process independent masks, or if given process constraints, specific for a target process. This design tool calculates the two-dimensional mask set required to produce a given three-dimensional model by investigating the vertical topology of the model.
Date: November 1, 2007
Creator: Schiek, Richard Louis & Schmidt, Rodney Cannon
Partner: UNT Libraries Government Documents Department

User`s manual for FAROW: Fatigue and reliability of wind turbine components: Version 1.1

Description: FAROW is a Computer program that assists in the probabilistic analysis of the Fatigue and Reliability of wind turbines. The fatigue lifetime of wind turbine components is calculated using functional forms for important input quantities. Parameters of these functions are defined in an input file as either constants or random variables. The user can select from a library of random variable distribution functions. FAROW uses structural reliability techniques to calculate the mean time to failure, probability of failure before a target lifetime, relative importance of each of the random inputs, and the sensitivity of the reliability to all input parameters. Monte Carlo simulation is also available. This user`s manual is intended to provide sufficient information to knowledgeably run the program and meaningfully interpret the results. The first chapter provides an overview of the approach and the results. Chapter 2 describes the formulation and assumptions used in the fatigue life calculations. Each of the input parameters is described in detail in Chapter 3 along with hints and warnings on usage. An explanation of the outputs is provided in Chapter 4. Two example problems are described and solved in Chapter 5, one for the case where extensive data are available and the other with limited data where the uncertainty is higher. A typical input file and the output files for the example problems are included in the appendices.
Date: November 1, 1994
Creator: Veers, P. S.; Winterstein, S. R.; Lange, C. H. & Wilson, T. A.
Partner: UNT Libraries Government Documents Department

8:1 thermal cavity problem

Description: We present results for the 8:1 thermal cavity problem using FIDAP on 3 meshes--each using 3 elements. A brief summary of related results is also included. This contribution comes via the rather versatile and general commercial finite element code, FIDAP. This code still offers the user a wide selection with respect to element choices, statement of governing equations, (e.g., advective form, divergence form) implicit time integrators (variable-step or fixed step, first-order or second-order), and solution techniques for both the nonlinear and linear sets of equations. We have tested quite a number of these variations on this problem; here we report on an interesting subset and will present the remainder at the conference.
Date: October 11, 2000
Creator: Gresho, P M & Sutton, S
Partner: UNT Libraries Government Documents Department

Comprehensive facility energy assessment using FEDS

Description: The energy savings and demand reduction opportunities at the Army`s National Training Center at Fort Irwin, California, were evaluated. The Fort Irwin analysis made use of the recently developed Facility Energy Decision Screening (FEDS) System Level-2 software tool. FEDS is a systematic, technology-neutral, and fuel-neutral approach to evaluating energy savings opportunities at large facilities. FEDS analyzes most major building end uses (e.g., heating, cooling, lighting, ventilation, and service hot water), including interactive effects (e.g., the effect of a lighting technology on heating and cooling loads). FEDS output provides specific cost, energy (and demand) charges, and life-cycle cost (LCC) information, by cost-effective energy resource opportunities (EROs). The remaining end uses common to large facilities (e.g., motors, transmission and distribution, vehicles) are analyzed using manual calculation methods. The present value (PV) of the installed cost of all EROs constituting the minimum LCC efficiency resource (i.e., cost-effective) at Fort Irwin is approximately $23.9 million in 1994 dollars (1994$). The PV of the energy and demand, operations and maintenance (O&M), and replacement savings associated with this investment is approximately $87.3 million, for an overall NPV of $63.6 million. This paper will describe the FEDS process and present detailed results of the comprehensive energy resource assessment conducted at Fort Irwin.
Date: December 1, 1994
Creator: Hadley, D.L.; Keller, J.M.; Richman, E.E. & Quinones, R.
Partner: UNT Libraries Government Documents Department