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DDES and IDDES of tandem cylinders.

Description: The paper presents an overview of the authors contribution to the BANC-I Workshop on the flow past tandem cylinders (Category 2). It includes an outline of the simulation approaches, numerics, and grid used, the major results of the simulations, their comparison with available experimental data, and some preliminary conclusions. The effect of varying the spanwise period in the simulations is strong for some quantities, and not others.
Date: September 9, 2010
Creator: Balakrishnan, R.; Garbaruk, A.; Shur, M.; Strelets, M.; Spalart, P.; Russia, New Technologies and Services - et al.
Partner: UNT Libraries Government Documents Department

ICGS system: system tables manual

Description: The Illinois Computing Graphics System (ICGS) is a batch system for a minicomputer. It executes a limited number of system programs, and provides facilities for rapid overlaying of these programs. This manual is intended to aid the system programmer in setting up the system tables. (auth)
Date: February 1, 1974
Creator: Mueller, D.H.
Partner: UNT Libraries Government Documents Department

Parallelization of ITOUGH2 using PVM

Description: ITOUGH2 inversions are computationally intensive because the forward problem must be solved many times to evaluate the objective function for different parameter combinations or to numerically calculate sensitivity coefficients. Most of these forward runs are independent from each other and can therefore be performed in parallel. Message passing based on the Parallel Virtual Machine (PVM) system has been implemented into ITOUGH2 to enable parallel processing of ITOUGH2 jobs on a heterogeneous network of Unix workstations. This report describes the PVM system and its implementation into ITOUGH2. Instructions are given for installing PVM, compiling ITOUGH2-PVM for use on a workstation cluster, the preparation of an 1.TOUGH2 input file under PVM, and the execution of an ITOUGH2-PVM application. Examples are discussed, demonstrating the use of ITOUGH2-PVM.
Date: October 1, 1998
Creator: Finsterle, Stefan
Partner: UNT Libraries Government Documents Department

A numerical investigation of scale-up effects on coke yields of a thermal cracking Riser reactor

Description: A validated computational fluid dynamics (CFD) computer code, ICRKFLO, was used to investigate the scale-up effects on the coke yields of thermal cracking riser factors. Comparisons were made for calculated coke yields of pilot- and commercial-scales riser units. Computational results show that the riser aspect ratio, reaction temperature, particle residence time, and particle/oil ratio have major impacts on the coke yield. A computational experiment was conducted to determine optimal operating conditions for a conceptual design of a commercial-scale riser unit. This experiment showed that the performance loss in scale-up from pilot to commercial scale may be almost completely recovered through optimizing the operating conditions after scale-up using the CFD simulations as a guide.
Date: May 1, 1995
Creator: Chang, S.L.; Lottes, S.A. & Petrick, M.
Partner: UNT Libraries Government Documents Department

Inverse modeling of a multistep outflow experiment fordetermining hysteretic hydraulic properties

Description: A new, closed-form hysteretic model of the capillary pressure-saturation and relative permeability-saturation relationship has been implemented into ITOUGH2. The hysteretic capillary pressure function is based on the van Genuchten model, with a modified version of the dependent domain model of Mualem to describe the scanning curves. Hysteresis in the relative permeability relations is considered to be mainly a result of nonwetting fluid entrap- ment. The hysteresis model was used in combination with inverse modeling techniques to examine the potential of a simple drainage- imbibition experiment to determine hysteretic hydraulic properties.
Date: May 1, 1998
Creator: Faybishenko, B.; Finsterle, S. & Sonnenborg, T.O.
Partner: UNT Libraries Government Documents Department

ISOcxx: The C++ portability package

Description: The level of C++ compliers' adherence to the ISO C++ standard varies considerably from compiler to compiler. This variability has significantly hindered users' attempts as standard-compliant C++ coding practices. ISOcxx is a software package that addresses such deficient aspects of users' C++ development environments. This portability package: (1) probes an environment to identify areas of non-compliance (defects) with the standard, and (2) supplies, where possible, compliance code so as to mitigate (cure) the ill effects of the detected defects. Each defect typically results from a feature that is required by the ISO C++ standard, but that a particular environment omits entirely, provides only incompletely, matches to an outdated draft of the standard, or otherwise incorrectly supports. A cure is applicable if test programs demonstrating the corresponding defect can be successfully compiled and run when the compliance code is incorporated. Where no compliance code is available, client code is nonetheless made aware of the defect and can thus avoid the offending construct. Thus, this package allows client code to be maximally compliant with the international C++ standard, yet still be acceptable to many otherwise-defective environments.
Date: February 9, 2000
Creator: Brown, W.E.
Partner: UNT Libraries Government Documents Department

Nonlinear image filtering within IDP++

Description: IDP++, image and data processing in C++, is a set of a signal processing libraries written in C++. It is a multi-dimension (up to four dimensions), multi-data type (implemented through templates) signal processing extension to C++. IDP++ takes advantage of the object-oriented compiler technology to provide ``information hiding.`` Users need only know C, not C++. Signals or data sets are treated like any other variable with a defined set of operators and functions. We here some examples of the nonlinear filter library within IDP++. Specifically, the results of MIN, MAX median, {alpha}-trimmed mean, and edge-trimmed mean filters as applied to a real aperture radar (RR) and synthetic aperture radar (SAR) data set.
Date: February 9, 1995
Creator: Lehman, S.K.; Wieting, M.G. & Brase, J.M.
Partner: UNT Libraries Government Documents Department

ITS Version 4.0: Electron/photon Monte Carlo transport codes

Description: The current publicly released version of the Integrated TIGER Series (ITS), Version 3.0, has been widely distributed both domestically and internationally, and feedback has been very positive. This feedback as well as our own experience have convinced us to upgrade the system in order to honor specific user requests for new features and to implement other new features that will improve the physical accuracy of the system and permit additional variance reduction. This presentation we will focus on components of the upgrade that (1) improve the physical model, (2) provide new and extended capabilities to the three-dimensional combinatorial-geometry (CG) of the ACCEPT codes, and (3) permit significant variance reduction in an important class of radiation effects applications.
Date: July 1, 1995
Creator: Halbleib, J.A,; Kensek, R.P. & Seltzer, S.M.
Partner: UNT Libraries Government Documents Department

ITS version 5.0 : the integrated TIGER series of coupled electron/photon Monte Carlo transport codes.

Description: ITS is a powerful and user-friendly software package permitting state of the art Monte Carlo solution of linear time-independent couple electron/photon radiation transport problems, with or without the presence of macroscopic electric and magnetic fields of arbitrary spatial dependence. Our goal has been to simultaneously maximize operational simplicity and physical accuracy. Through a set of preprocessor directives, the user selects one of the many ITS codes. The ease with which the makefile system is applied combines with an input scheme based on order-independent descriptive keywords that makes maximum use of defaults and internal error checking to provide experimentalists and theorists alike with a method for the routine but rigorous solution of sophisticated radiation transport problems. Physical rigor is provided by employing accurate cross sections, sampling distributions, and physical models for describing the production and transport of the electron/photon cascade from 1.0 GeV down to 1.0 keV. The availability of source code permits the more sophisticated user to tailor the codes to specific applications and to extend the capabilities of the codes to more complex applications. Version 5.0, the latest version of ITS, contains (1) improvements to the ITS 3.0 continuous-energy codes, (2)multigroup codes with adjoint transport capabilities, and (3) parallel implementations of all ITS codes. Moreover the general user friendliness of the software has been enhanced through increased internal error checking and improved code portability.
Date: June 1, 2004
Creator: Franke, Brian Claude; Kensek, Ronald Patrick & Laub, Thomas William
Partner: UNT Libraries Government Documents Department

Adjoint electron-photon transport Monte Carlo calculations with ITS

Description: A general adjoint coupled electron-photon Monte Carlo code for solving the Boltzmann-Fokker-Planck equation has recently been created. It is a modified version of ITS 3.0, a coupled electronphoton Monte Carlo code that has world-wide distribution. The applicability of the new code to radiation-interaction problems of the type found in space environments is demonstrated.
Date: February 1, 1995
Creator: Lorence, L.J.; Kensek, R.P.; Halbleib, J.A. & Morel, J.E.
Partner: UNT Libraries Government Documents Department

Monitoring and visualizing information resources

Description: The continuous increase in information necessitates monitoring and display techniques that maximize comprehension yet minimize effort. In this paper, we discuss the use of hypertools, confluent zoom and graphical encoding of text as solutions to this problem, and we introduce Irwin and information resource and display tool.
Date: July 1, 1996
Creator: McCrickard, D.S. & Rowan, T.H.
Partner: UNT Libraries Government Documents Department

Three-dimensional finite element simulations of the rolling of superconducting wire

Description: The goal of this work was to show the utility of using finite-element simulations to ascertain the quality of superconducting tape, created by the repeated rolling of an initially round wire. Steady-state simulations of the rolling reductions of a two, material superconducting wire were performed using ISAIAH, a three-dimensional nonlinear finite-element code. The simulations were done in conjunction with Dave Korzekwa at Los Alamos National Laboratory to produce results that could be compared with experimental findings. Results indicate that ISAIAH is capable of producing potentially useful data, but further work is necessary to obtain meaningful quantitative comparisons between simulations and experiments. This report describes the simulations that have been conducted to date and also indicates several directions for the future development of this research.
Date: November 17, 1993
Creator: Davies, M.A.; Boyce, D.E. & Dawson, P.R.
Partner: UNT Libraries Government Documents Department

Air quality investigations of the Sandia National Laboratories Sol se Mete Aerial Cable Facility

Description: The air quality implications of the test and evaluation activities at the Sandia National Laboratories Sol se Mete Aerial Cable Facility are examined. All facets of the activity that affect air quality are considered. Air contaminants produced directly include exhaust products of rocket motors used to accelerate test articles, dust and gas from chemical explosives, and exhaust gases from electricity generators in the test arenas. Air contaminants produced indirectly include fugitive dust and exhaust contaminants from vehicles used to transport personnel and material to the test area, and effluents produced by equipment used to heat the project buildings. Both the ongoing program and the proposed changes in the program are considered. Using a reliable estimate of th maximum annual testing level, the quantities of contaminants released by project activities ar computed either from known characteristics of test items or from EPA-approved emission factors Atmospheric concentrations of air contaminants are predicted using EPA dispersion models. The predicted quantities and concentrations are evaluated in relation to Federal, New Mexico, an Bernalillo County air quality regulations and the human health and safety standards of the American Conference of Governmental Industrial Hygienists.
Date: December 1994
Creator: Gutman, W. M. & Silver, R. J.
Partner: UNT Libraries Government Documents Department

Methodologies for extracting kinetic constants for multiphase reacting flow simulation

Description: Flows in industrial reactors often involve complex reactions of many species. A computational fluid dynamics (CFD) computer code, ICRKFLO, was developed to simulate multiphase, multi-species reacting flows. The ICRKFLO uses a hybrid technique to calculate species concentration and reaction for a large number of species in a reacting flow. This technique includes a hydrodynamic and reacting flow simulation with a small but sufficient number of lumped reactions to compute flow field properties followed by a calculation of local reaction kinetics and transport of many subspecies (order of 10 to 100). Kinetic rate constants of the numerous subspecies chemical reactions are difficult to determine. A methodology has been developed to extract kinetic constants from experimental data efficiently. A flow simulation of a fluid catalytic cracking (FCC) riser was successfully used to demonstrate this methodology.
Date: March 1, 1997
Creator: Chang, S.L.; Lottes, S.A.; Golchert, B.; Petrick, M. & Zhou, C.Q.
Partner: UNT Libraries Government Documents Department

Evaluation of multi-phase heat transfer and droplet evaporation in petroleum cracking flows

Description: A computer code ICRKFLO was used to simulate the multiphase reacting flow of fluidized catalytic cracking (FCC) riser reactors. The simulation provided a fundamental understanding of the hydrodynamics and heat transfer processes in an FCC riser reactor, critical to the development of a new high performance unit. The code was able to make predictions that are in good agreement with available pilot-scale test data. Computational results indicate that the heat transfer and droplet evaporation processes have a significant impact on the performance of a pilot-scale FCC unit. The impact could become even greater on scale-up units.
Date: April 1, 1996
Creator: Chang, S.L.; Lottes, S.A.; Petrick, M. & Zhou, C.Q.
Partner: UNT Libraries Government Documents Department

TRANSIMS simulation output subsystem for IOC-1

Description: The output subsystem collects data from a running microsimulation, stores the data for future use, and manages the subsequent retrieval of the data. It forms a layer separating the other subsystems from the actual data files so that the other subsystems do not need to access the data files at the physical level or deal with the physical location and organization of the files. This subsystem also allows the user to specify what data is collected and retrieved, and to filter it by space and time. The collection occurs in a distributed manner such that the subsystem`s impact on the microsimulation performance is minimized; the retrieval provides a unified view of the distributed data.
Date: April 2, 1997
Creator: Kerkbigler, K.P. & Bush, B.W.
Partner: UNT Libraries Government Documents Department

Flow simulation of the Component Development Integration Facility magnetohydrodynamic power train system

Description: This report covers application of Argonne National Laboratory`s (ANL`s) computer codes to simulation and analysis of components of the magnetohydrodynamic (MHD) power train system at the Component Development and Integration Facility (CDIF). Major components of the system include a 50-MWt coal-fired, two-stage combustor and an MHD channel. The combustor, designed and built by TRW, includes a deswirl section between the first and the second-stage combustor and a converging nozzle following the second-stage combustor, which connects to the MHD channel. ANL used computer codes to simulate and analyze flow characteristics in various components of the MHD system. The first-stage swirl combustor was deemed a mature technology and, therefore, was not included in the computer simulation. Several versions of the ICOMFLO computer code were used for the deswirl section and second-stage combustor. The MGMHD code, upgraded with a slag current leakage submodel, was used for the MHD channel. Whenever possible data from the test facilities were used to aid in calibrating parameters in the computer code, to validate the computer code, or to set base-case operating conditions for computations with the computer code. Extensive sensitivity and parametric studies were done on cold-flow mixing in the second-stage combustor, reacting flow in the second-stage combustor and converging nozzle, and particle-laden flow in the deswirl zone of the first-stage combustor, the second-stage combustor, and the converging nozzle. These simulations with subsequent analysis were able to show clearly in flow patterns and various computable measures of performance a number of sensitive and problematical areas in the design of the power train. The simulations of upstream components also provided inlet parameter profiles for simulation of the MHD power generating channel. 86 figs., 18 tabs.
Date: November 1, 1997
Creator: Chang, S.L.; Lottes, S.A.; Bouillard, J.X. & Petrick, M.
Partner: UNT Libraries Government Documents Department


Description: Current ideas for designing neutrino factories [ 1,2] and muon colliders [3] require unique configurations of fields and materials to prepare the muon beam for acceleration. This so-called front end system must accomplish the goals of phase rotation, bunching and cooling. We have continued the development of a 3-D tracking code, ICOOL [4], for examining possible muon collider front end configurations. A system is described in terms of a series of longitudinal regions with associated material and field properties. The tracking takes place in a coordinate system that follows a reference orbit through the system. The code takes into account decays and interactions of {approx}50-500 MeV/c muons in matter. Material geometry regions include cylinders and wedges. A number of analytic models are provided for describing the field configurations. Simple diagnostics are built into the code, including calculation of emittances and correlations, longitudinal traces, histograms and scatter plots. A number of auxiliary codes can be used for pre-processing, post-processing and optimization.
Date: September 28, 2001
Creator: FERNOW,R.C.
Partner: UNT Libraries Government Documents Department