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Sierra Toolkit Manual Version 4.48

Team, Sierra T.

This report provides documentation for the SIERRA Toolkit (STK) modules. STK modules are intended to provide infrastructure that assists the development of computational engineering software such as finite-element analysis applications. STK includes modules for unstructured-mesh data structures, reading/writing mesh files, geometric proximity search, and various utilities. This document contains a chapter for each module, and each chapter contains overview descriptions and usage examples. Usage examples are primarily code listings which are generated from working test programs that are included in the STK code-base. A goal of this approach is to ensure that the usage examples will not fall out of date. This page intentionally left blank.

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TYPE SAND Report YEAR 2018
DOIOSTI

Analyses in Support of Risk-Informed Natural Gas Vehicle Maintenance Facility Codes and Standards: Phase II

Blaylock, Myra L.; Lafleur, Angela (Chris); Muna, Alice B.; Ehrhart, Brian D.

Safety standards development for maintenance facilities of liquid and compressed natural gas fueled vehicles is required to ensure proper facility design and operating procedures. Standard development organizations are utilizing risk-informed concepts to develop natural gas vehicle (NGV) codes and standards so that maintenance facilities meet acceptable risk levels. The present report summarizes Phase II work for existing NGV repair facility code requirements and highlights inconsistencies that need quantitative analysis into their effectiveness. A Hazardous and Operability study was performed to identify key scenarios of interest using risk ranking. Detailed simulations and modeling were performed to estimate the location and behavior of natural gas releases based on these scenarios. Specific code conflicts were identified, and ineffective code requirements were highlighted and resolutions proposed. These include ventilation rate basis on area or volume, as well as a ceiling offset which seems ineffective at protecting against flammable gas concentrations. ACKNOWLEDGEMENTS The authors gratefully acknowledge Bill Houf (SNL -- Retired) for his assistance with the set-up and post-processing of the numerical simulations. The authors also acknowledge Doug Horne (retired) for his helpful discussions. We would also like to acknowledge the support from the Clean Cities program of DOE's Vehicle Technology Office.

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TYPE SAND Report YEAR 2018
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Sierra/Solid Mechanics 4.48 User's Guide

Merewether, Mark T.; Crane, Nathan K.; De Frias, Gabriel J.; San LeSan; Littlewood, David J.; Mosby, Matthew D.; Pierson, Kendall H.; Porter, Vicki L.; Shelton, Timothy R.; Thomas, Jesse D.; Tupek, Michael R.; Veilleux, Michael G.; Gampert, Scott O.; Xavier, Patrick G.; Plews, Julia A.

Sierra/SolidMechanics (Sierra/SM) is a Lagrangian, three-dimensional code for finite element analysis of solids and structures. It provides capabilities for explicit dynamic, implicit quasistatic and dynamic analyses. The explicit dynamics capabilities allow for the efficient and robust solution of models with extensive contact subjected to large, suddenly applied loads. For implicit problems, Sierra/SM uses a multi-level iterative solver, which enables it to effectively solve problems with large deformations, nonlinear material behavior, and contact. Sierra/SM has a versatile library of continuum and structural elements, and a large library of material models. The code is written for parallel computing environments enabling scalable solutions of extremely large problems for both implicit and explicit analyses. It is built on the SIERRA Framework, which facilitates coupling with other SIERRA mechanics codes. This document describes the functionality and input syntax for Sierra/SM.

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TYPE SAND Report YEAR 2018
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The Crank Nicolson Time Integrator for EMPHASIS

Mcgregor, Duncan A.O.; Love, Edward; Kramer, Richard M.J.

We investigate the use of implicit time integrators for finite element time domain approximations of Maxwell's equations in vacuum. We discretize Maxwell's equations in time using Crank-Nicolson and in 3D space using compatible finite elements. We solve the system by taking a single step of Newton's method and inverting the Eddy-Current Schur complement allowing for the use of standard preconditioning techniques. This approach also generalizes to more complex material models that can include the Unsplit PML. We present verification results and demonstrate performance at CFL numbers up to 1000.

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TYPE SAND Report YEAR 2018
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Final Documentation: Incident Management And Probabilities Courses of action Tool (IMPACT)

Edwards, Donna M.; Ray, Jaideep; Tucker, Mark D.; Whetzel, Jonathan H.; Cauthen, Katherine R.

This report pulls together the documentation produced for the IMPACT tool, a software-based decision support tool that provides situational awareness, incident characterization, and guidance on public health and environmental response strategies for an unfolding bio-terrorism incident.

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TYPE SAND Report YEAR 2018
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Measuring Balance Across Multiple Radar Receiver Channels

Doerry, Armin W.; Bickel, Douglas L.

When radar receivers employ multiple channels, the general intent is for the receive channels to be as alike as possible, if not as ideal as possible. This is usually done via prudent hardware design, supplemented by system calibration. Towards this end, we require a quality metric for ascertaining the goodness of a radar channel, and the degree of match to sibling channels. We propose a relevant and usable metric to do just that. Acknowledgements: This report was the result of an unfunded research and development activity.

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TYPE SAND Report YEAR 2018
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Sierra/SolidMechanics 4.46 Example Problems Manual

Plews, Julia A.; Crane, Nathan K.; De Frias, Gabriel J.; San LeSan; Littlewood, David J.; Merewether, Mark T.; Mosby, Matthew D.; Pierson, Kendall H.; Porter, Vicki L.; Shelton, Timothy R.; Thomas, Jesse D.; Tupek, Michael R.; Veilleux, Michael G.

Presented in this document are tests that exist in the Sierra/SolidMechanics example problem suite, which is a subset of the Sierra/SM regression and performance test suite. These examples showcase common and advanced code capabilities. A wide variety of other regression and verification tests exist in the Sierra/SM test suite that are not included in this manual.

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TYPE SAND Report YEAR 2018
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Results 31001–31200 of 99,299
Results 31001–31200 of 99,299