Sample records for material failure model

  1. Experiments for calibration and validation of plasticity and failure material modeling: 304L stainless steel.

    SciTech Connect (OSTI)

    Lee, Kenneth L.; Korellis, John S.; McFadden, Sam X.

    2006-01-01T23:59:59.000Z

    Experimental data for material plasticity and failure model calibration and validation were obtained from 304L stainless steel. Model calibration data were taken from smooth tension, notched tension, and compression tests. Model validation data were provided from experiments using thin-walled tube specimens subjected to path dependent combinations of internal pressure, extension, and torsion.

  2. Multiscale modeling and simulation of deformation and failure mechanisms of hierarchical alpha-helical protein materials

    E-Print Network [OSTI]

    Bertaud, Jeremie

    2009-01-01T23:59:59.000Z

    Alpha-helical (AH) protein structures are critical building blocks of life, representing the key constituents of biological materials such as cells, hair, hoof and wool, where they assemble to form hierarchical structures. ...

  3. IR DIAGNOSTICS FOR DYNAMIC FAILURE OF MATERIALS

    SciTech Connect (OSTI)

    McElfresh, M; DeTeresa, S

    2006-02-13T23:59:59.000Z

    This project explores the thermodynamics of dynamic deformation and failure of materials using high-speed spatially-resolved infrared (IR) measurements of temperature. During deformation mechanical work is converted to different forms of energy depending on the deformation processes. For example, it can be dissipated as heat in purely plastic deformation, stored as strain energy in dislocations in metals and in oriented polymeric molecular structures, and expended during the generation of new surfaces during damage and fracture. The problem of how this work is converted into these various forms is not well understood. In fact, there exists a controversy for the relatively simple case regarding the amount of work dissipated as heat during uniform plastic deformation. The goals of this work are to develop dynamic IR temperature measurement techniques and then apply them to gain a better understanding of the dynamic failure processes in both metals and polymeric composite materials. The experimental results will be compared against predictions of existing constitutive models and guide the development of higher fidelity models if needed.

  4. Numerical Modeling of Failure in Magnesium Alloys under Axial Compression and Bending for Crashworthiness Applications.

    E-Print Network [OSTI]

    Ali, Usman

    2012-01-01T23:59:59.000Z

    ??Numerical modeling of failure was performed for magnesium alloys with circular and square cross-sections under axial compression. The failure criterion was employed using material model… (more)

  5. Correlation of electrical reactor cable failure with materials degradation

    SciTech Connect (OSTI)

    Stuetzer, O.M.

    1986-03-01T23:59:59.000Z

    Complete circuit failure (shortout) of electrical cables typically used in nuclear power plant containments is investigated. Failure modes are correlated with the mechanical deterioration of the elastomeric cable materials. It is found that for normal reactor operation, electrical cables are reliable and safe over very long periods. During high temperature excursions, however, cables pulled across corners under high stress may short out due to conductor creep. Severe cracking will occur in short times during high temperatures (>150/sup 0/C) and in times of the order of years at elevated temperatures (100/sup 0/C to 140/sup 0/C). A theoretical treatment of stress distribution responsible for creep and for cracking by J.E. Reaugh of Science Applications, Inc. is contained in the Appendix. 29 refs., 32 figs.

  6. A simple approach to modeling ductile failure.

    SciTech Connect (OSTI)

    Wellman, Gerald William

    2012-06-01T23:59:59.000Z

    Sandia National Laboratories has the need to predict the behavior of structures after the occurrence of an initial failure. In some cases determining the extent of failure, beyond initiation, is required, while in a few cases the initial failure is a design feature used to tailor the subsequent load paths. In either case, the ability to numerically simulate the initiation and propagation of failures is a highly desired capability. This document describes one approach to the simulation of failure initiation and propagation.

  7. Modelling of dependence between critical failure and preventive maintenance

    E-Print Network [OSTI]

    Langseth, Helge

    Modelling of dependence between critical failure and preventive maintenance: The repair alert model, or a preventive maintenance (PM) action, where the latter will prevent the failure. It is reasonable to expect that the failure can be avoided by a possible preventive maintenance (PM) at some random time Z. If Z

  8. Statistical Modeling of Corrosion Failures in Natural Gas Transmission Pipelines

    E-Print Network [OSTI]

    Cobanoglu, Mustafa Murat

    2014-03-28T23:59:59.000Z

    and deterioration processes in pipeline networks. Therefore, pipeline operators need to rethink their corrosion prevention strategies. These results of corrosion failures are forcing the companies to develop accurate maintenance models based on failure frequency...

  9. Large-Scale Atomistic Simulations of Material Failure

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Abraham, Farid [IBM Almaden Research; Duchaineau, Mark [LLNL; Wirth, Brian [LLNL; Heidelberg,; Seager, Mark [LLNL; De La Rubia, Diaz [LLNL

    These simulations from 2000 examine the supersonic propagation of cracks and the formation of complex junction structures in metals. Eight simulations concerning brittle fracture, ductile failure, and shockless compression are available.

  10. Reactor Materials Program process water piping indirect failure frequency

    SciTech Connect (OSTI)

    Daugherty, W.L.

    1989-10-30T23:59:59.000Z

    Following completion of the probabilistic analyses, the LOCA Definition Project has been subject to various external reviews, and as a result the need for several revisions has arisen. This report updates and summarizes the indirect failure frequency analysis for the process water piping. In this report, a conservatism of the earlier analysis is removed, supporting lower failure frequency estimates. The analysis results are also reinterpreted in light of subsequent review comments.

  11. Modelling of dependence between critical failure and preventive maintenance

    E-Print Network [OSTI]

    Langseth, Helge

    Modelling of dependence between critical failure and preventive maintenance: The repair alert model, or a preventive maintenance (PM) action, where the latter will prevent the failure. It is reasonable to expect be avoided by a possible preventive maintenance (PM) at some random time Z. If Z

  12. Failure in shear bands for granular materials: thermo-hydro-chemo-mechanical effects

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Failure in shear bands for granular materials: thermo-hydro-chemo- mechanical effects M. VEVEAKIS depends on the chemical reaction characteristics and that micro-inertia due to grain translations

  13. Modeling Stress Strain Relationships and Predicting Failure Probabilities For Graphite Core Components

    SciTech Connect (OSTI)

    Duffy, Stephen

    2013-09-09T23:59:59.000Z

    This project will implement inelastic constitutive models that will yield the requisite stress-strain information necessary for graphite component design. Accurate knowledge of stress states (both elastic and inelastic) is required to assess how close a nuclear core component is to failure. Strain states are needed to assess deformations in order to ascertain serviceability issues relating to failure, e.g., whether too much shrinkage has taken place for the core to function properly. Failure probabilities, as opposed to safety factors, are required in order to capture the bariability in failure strength in tensile regimes. The current stress state is used to predict the probability of failure. Stochastic failure models will be developed that can accommodate possible material anisotropy. This work will also model material damage (i.e., degradation of mechanical properties) due to radiation exposure. The team will design tools for components fabricated from nuclear graphite. These tools must readily interact with finite element software--in particular, COMSOL, the software algorithm currently being utilized by the Idaho National Laboratory. For the eleastic response of graphite, the team will adopt anisotropic stress-strain relationships available in COMSO. Data from the literature will be utilized to characterize the appropriate elastic material constants.

  14. Analysis of the causes of failure in high chrome oxide refractory materials from slagging gasifiers

    SciTech Connect (OSTI)

    Bennett, J.P.; Kwong, K.-S.; Powell, C.A.; Thomas, H.; Krabbe, R.A.

    2006-03-01T23:59:59.000Z

    High Cr2O3 refractory materials are used to line the hot face of slagging gasifiers. Gasifiers are reaction chambers that convert water, oxygen, and a carbon feedstock into CO, H2, and methane at temperatures as high as 1575oC and pressures up to 1000 psi. Ash in the carbon feedstock liquefies, erodes and corrodes the gasifier’s refractory liner, contributing to liner failure within a few months to two years. The failure of a refractory liner decreases a gasifier’s on-line availability and causes costly system downtime and repairs. Many factors contribute to refractory lining failure, including slag penetration and corrosion, thermal cycling, gasifier environment, and mechanical loads. The results of refractory post-mortem failure analysis and how observations relate to gasifier service life will be discussed.

  15. Accelerated Failure Time Regression Model with a Regression Model of Surviving Fraction: An Application to the Analysis of RPermanent EmploymentS in Japan

    E-Print Network [OSTI]

    Kazuo Yamaguchi

    2011-01-01T23:59:59.000Z

    other hand, for any given accelerated failure-time model, weconsidered improvements of accelerated failure-time models.Although representative accelerated failure-time models can

  16. Failure by fracture and fatigue in 'NANO' and 'BIO'materials

    SciTech Connect (OSTI)

    Ritchie, R.O.; Muhlstein, C.L.; Nalla, R.K.

    2003-12-19T23:59:59.000Z

    The behavior of nanostructured materials/small-volumestructures and biologi-cal/bio-implantable materials, so-called "nano"and "bio" materials, is currently much in vogue in materials science. Oneaspect of this field, which to date has received only limited attention,is their fracture and fatigue properties. In this paper, we examine twotopics in this area, namely the premature fatigue failure ofsilicon-based micron-scale structures for microelectromechanical systems(MEMS), and the fracture properties of mineralized tissue, specificallyhuman bone.

  17. Physica A 264 (1999) 7583 Incipient failure in sandpile models

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Physica A 264 (1999) 75­83 Incipient failure in sandpile models Onuttom Narayana; , Sidney R. Nagelb aDepartment of Physics, University of California, Santa Cruz, CA 95064, USA bThe James Franck Institute and Department of Physics, University of Chicago, Chicago, IL 60637, USA Received 13 October 1998

  18. Bayesian failure probability model sensitivity study. Final report

    SciTech Connect (OSTI)

    Not Available

    1986-05-30T23:59:59.000Z

    The Office of the Manager, National Communications System (OMNCS) has developed a system-level approach for estimating the effects of High-Altitude Electromagnetic Pulse (HEMP) on the connectivity of telecommunications networks. This approach incorporates a Bayesian statistical model which estimates the HEMP-induced failure probabilities of telecommunications switches and transmission facilities. The purpose of this analysis is to address the sensitivity of the Bayesian model. This is done by systematically varying two model input parameters--the number of observations, and the equipment failure rates. Throughout the study, a non-informative prior distribution is used. The sensitivity of the Bayesian model to the noninformative prior distribution is investigated from a theoretical mathematical perspective.

  19. Failure Predictions for VHTR Core Components using a Probabilistic Contiuum Damage Mechanics Model

    SciTech Connect (OSTI)

    Fok, Alex

    2013-10-30T23:59:59.000Z

    The proposed work addresses the key research need for the development of constitutive models and overall failure models for graphite and high temperature structural materials, with the long-term goal being to maximize the design life of the Next Generation Nuclear Plant (NGNP). To this end, the capability of a Continuum Damage Mechanics (CDM) model, which has been used successfully for modeling fracture of virgin graphite, will be extended as a predictive and design tool for the core components of the very high- temperature reactor (VHTR). Specifically, irradiation and environmental effects pertinent to the VHTR will be incorporated into the model to allow fracture of graphite and ceramic components under in-reactor conditions to be modeled explicitly using the finite element method. The model uses a combined stress-based and fracture mechanics-based failure criterion, so it can simulate both the initiation and propagation of cracks. Modern imaging techniques, such as x-ray computed tomography and digital image correlation, will be used during material testing to help define the baseline material damage parameters. Monte Carlo analysis will be performed to address inherent variations in material properties, the aim being to reduce the arbitrariness and uncertainties associated with the current statistical approach. The results can potentially contribute to the current development of American Society of Mechanical Engineers (ASME) codes for the design and construction of VHTR core components.

  20. Mathematical modelings of smart materials and structures

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Mathematical modelings of smart materials and structures Christian Licht , Thibaut Weller mathematical models of smart materials and smart structures. Smart materials are materials which present perturbations methods, asymptotic analysis, plates and rods models. 1 Introduction Smart materials present

  1. RECONFIGURING POWER SYSTEMS TO MINIMIZE CASCADING FAILURES: MODELS AND ALGORITHMS

    SciTech Connect (OSTI)

    Bienstock, Daniel

    2014-04-11T23:59:59.000Z

    the main goal of this project was to develop new scientific tools, based on optimization techniques, with the purpose of controlling and modeling cascading failures of electrical power transmission systems. We have developed a high-quality tool for simulating cascading failures. The problem of how to control a cascade was addressed, with the aim of stopping the cascade with a minimum of load lost. Yet another aspect of cascade is the investigation of which events would trigger a cascade, or more appropriately the computation of the most harmful initiating event given some constraint on the severity of the event. One common feature of the cascade models described (indeed, of several of the cascade models found in the literature) is that we study thermally-induced line tripping. We have produced a study that accounts for exogenous randomness (e.g. wind and ambient temperature) that could affect the thermal behavior of a line, with a focus on controlling the power flow of the line while maintaining safe probability of line overload. This was done by means of a rigorous analysis of a stochastic version of the heat equation. we incorporated a model of randomness in the behavior of wind power output; again modeling an OPF-like problem that uses chance-constraints to maintain low probability of line overloads; this work has been continued so as to account for generator dynamics as well.

  2. In-Vessel Coil Material Failure Rate Estimates for ITER Design Use

    SciTech Connect (OSTI)

    L. C. Cadwallader

    2013-01-01T23:59:59.000Z

    The ITER international project design teams are working to produce an engineering design for construction of this large tokamak fusion experiment. One of the design issues is ensuring proper control of the fusion plasma. In-vessel magnet coils may be needed for plasma control, especially the control of edge localized modes (ELMs) and plasma vertical stabilization (VS). These coils will be lifetime components that reside inside the ITER vacuum vessel behind the blanket modules. As such, their reliability is an important design issue since access will be time consuming if any type of repair were necessary. The following chapters give the research results and estimates of failure rates for the coil conductor and jacket materials to be used for the in-vessel coils. Copper and CuCrZr conductors, and stainless steel and Inconel jackets are examined.

  3. Modeling Coulombic failure of sea ice with leads Alexander V. Wilchinsky1

    E-Print Network [OSTI]

    Feltham, Daniel

    Modeling Coulombic failure of sea ice with leads Alexander V. Wilchinsky1 and Daniel L. Feltham1 ice failure under lowconfinement compression is modeled with a linear Coulombic criterion that can of anisotropy we consider a simplified anisotropic sea ice model where the sea ice thickness depends

  4. A robust Bayesian approach to modeling epistemic uncertainty in common-cause failure models

    SciTech Connect (OSTI)

    Matthias C. M. Troffaes; Gero Walter; Dana Kelly

    2014-05-01T23:59:59.000Z

    In a standard Bayesian approach to the alpha-factor model for common-cause failure, a precise Dirichlet prior distribution models epistemic uncertainty in the alpha-factors. This Dirichlet prior is then updated with observed data to obtain a posterior distribution, which forms the basis for further inferences. In this paper, we adapt the imprecise Dirichlet model of Walley to represent epistemic uncertainty in the alpha-factors. In this approach, epistemic uncertainty is expressed more cautiously via lower and upper expectations for each alpha-factor, along with a learning parameter which determines how quickly the model learns from observed data. For this application, we focus on elicitation of the learning parameter, and find that values in the range of 1 to 10 seem reasonable. The approach is compared with Kelly and Atwood's minimally informative Dirichlet prior for the alpha-factor model, which incorporated precise mean values for the alpha-factors, but which was otherwise quite diffuse. Next, we explore the use of a set of Gamma priors to model epistemic uncertainty in the marginal failure rate, expressed via a lower and upper expectation for this rate, again along with a learning parameter. As zero counts are generally less of an issue here, we find that the choice of this learning parameter is less crucial. Finally, we demonstrate how both epistemic uncertainty models can be combined to arrive at lower and upper expectations for all common-cause failure rates. Thereby, we effectively provide a full sensitivity analysis of common-cause failure rates, properly reflecting epistemic uncertainty of the analyst on all levels of the common-cause failure model.

  5. Dependable Systems of Systems PCE4: Models of Organisational Failure1 IST-1999-11585

    E-Print Network [OSTI]

    Newcastle upon Tyne, University of

    Dependable Systems of Systems PCE4: Models of Organisational Failure1 DSoS IST-1999 Report Version: Deliverable (PCE4) Report Preparation Date: 1 December 2002 Classification: Public Technology" Programme (1998- 2002) #12;Dependable Systems of Systems PCE4: Models of Organisational Failure2

  6. HYPERELASTIC MODELS FOR GRANULAR MATERIALS

    SciTech Connect (OSTI)

    Humrickhouse, Paul W; Corradini, Michael L

    2009-01-29T23:59:59.000Z

    A continuum framework for modeling of dust mobilization and transport, and the behavior of granular systems in general, has been reviewed, developed and evaluated for reactor design applications. The large quantities of micron-sized particles expected in the international fusion reactor design, ITER, will accumulate into piles and layers on surfaces, which are large relative to the individual particle size; thus, particle-particle, rather than particle-surface, interactions will determine the behavior of the material in bulk, and a continuum approach is necessary and justified in treating the phenomena of interest; e.g., particle resuspension and transport. The various constitutive relations that characterize these solid particle interactions in dense granular flows have been discussed previously, but prior to mobilization their behavior is not even fluid. Even in the absence of adhesive forces between particles, dust or sand piles can exist in static equilibrium under gravity and other forces, e.g., fluid shear. Their behavior is understood to be elastic, though not linear. The recent “granular elasticity” theory proposes a non-linear elastic model based on “Hertz contacts” between particles; the theory identifies the Coulomb yield condition as a requirement for thermodynamic stability, and has successfully reproduced experimental results for stress distributions in sand piles. The granular elasticity theory is developed and implemented in a stand- alone model and then implemented as part of a finite element model, ABAQUS, to determine the stress distributions in dust piles subjected to shear by a fluid flow. We identify yield with the onset of mobilization, and establish, for a given dust pile and flow geometry, the threshold pressure (force) conditions on the surface due to flow required to initiate it. While the granular elasticity theory applies strictly to cohesionless granular materials, attractive forces are clearly important in the interaction of micron-sized particles; extension of the theory to account for these effects is also considered. A set of continuum models are proposed for use in the future dust transport modeling.

  7. Micromechanical Damage Models for Continuous Fiber Reinforced Composite Materials

    E-Print Network [OSTI]

    Wu, Yi

    2013-01-01T23:59:59.000Z

    reinforced plastic matrix composite, Material and Design,1995). Failure of fiber composites: a lattice green functionreinforced titanium composites, Composites Science and

  8. High Accuracy 65nm OPC Verification: Full Process Window Model vs. Critical Failure ORC

    E-Print Network [OSTI]

    Boyer, Edmond

    High Accuracy 65nm OPC Verification: Full Process Window Model vs. Critical Failure ORC Amandine of Mask Rule Checking (MRC) and Optical Rule Checking (ORC) have become indispensable tools for ensuring, a technique known as Critical Failure ORC (CFORC) was introduced that uses optical parameters from aerial

  9. Waves and propagation failure in discrete space models with nonlinear coupling and

    E-Print Network [OSTI]

    Waves and propagation failure in discrete space models with nonlinear coupling and feedback Markus by the linearisation ahead of the wave front. Wave propagation (and failure) is studied when the homogeneous dynamics are bistable. Simulations show that waves may propagate in either direction, or may be pinned. A Lyapunov

  10. A MAINTENANCE MODEL FOR COMPONENTS EXPOSED TO SEVERAL FAILURE MECHANISMS

    E-Print Network [OSTI]

    Langseth, Helge

    . The preventive maintenance (PM) is performed periodically with some fixed period , but PM can also be performed describe the "goodness" of the maintenance crew; their ability to prevent failures by performing thorough is assumed to undergo preventive maintenance (PM), usually at fixed time periods > 0. In addition

  11. High Temperature Expansion Due to Compression Test for the Determination of a Cladding Material Failure Criterion under RIA Loading Conditions

    SciTech Connect (OSTI)

    Le Saux, M.; Poussard, C.; Averty, X.; Sainte Catherine, C.; Carassou, S. [CEA-Saclay, DEN/DMN/SEMI, 91191 Gif-Sur-Yvette (France); Besson, J. [Centre des Materiaux, Mines Paris, CNRS UMR 7633, BP 87, 91003 Evry (France)

    2007-07-01T23:59:59.000Z

    This paper is mainly dedicated to the development of an out-of-pile test reproducing the thermo-mechanical loading conditions encountered during the first stage of a Reactivity Initiated Accidents (RIA) transient, dominated by Pellet Clad Mechanical Interaction (PCMI). In particular, the strain-controlled clad loading under high strain rate associated with temperatures up to 600 deg. C expected during the PCMI phase is simulated by an Expansion Due to Compression (EDC) test achievable at high temperature. The use of appropriate materials for the inner pellet made it possible to achieve the tests from 20 deg. C up to 900 deg. C. The interpretation of the test data is supported by Finite Element Analysis (FEA) including parameters tuned using an inverse method coupling FEA and tests results. A deformation model, identified upon the PROMETRA (Transient Mechanical Properties) experimental database and describing the anisotropic viscoplastic behavior of Cold-Worked Stress Relieved Zircaloy-4 cladding alloys under typical RIA loading conditions, is exploited. The combined analysis of experimental results and finite element simulations provides a deeper understanding of the deformation mode (near pure hoop tension) that arises during the tests. The failure mode appears to be representative of that obtained on tubes during the PCMI stage of RIA experiments. An appropriate device is currently developed in order to reach a bi-axiality of the loading path closer to that expected during the PCMI stage (between plane-strain and equal-biaxial tension). (authors)

  12. ARRA: Reconfiguring Power Systems to Minimize Cascading Failures - Models and Algorithms

    SciTech Connect (OSTI)

    Dobson, Ian [Iowa State University] [Iowa State University; Hiskens, Ian [Unversity of Michigan] [Unversity of Michigan; Linderoth, Jeffrey [University of Wisconsin-Madison] [University of Wisconsin-Madison; Wright, Stephen [University of Wisconsin-Madison] [University of Wisconsin-Madison

    2013-12-16T23:59:59.000Z

    Building on models of electrical power systems, and on powerful mathematical techniques including optimization, model predictive control, and simluation, this project investigated important issues related to the stable operation of power grids. A topic of particular focus was cascading failures of the power grid: simulation, quantification, mitigation, and control. We also analyzed the vulnerability of networks to component failures, and the design of networks that are responsive to and robust to such failures. Numerous other related topics were investigated, including energy hubs and cascading stall of induction machines

  13. A Predictive Model of Fragmentation using Adaptive Mesh Refinement and a Hierarchical Material Model

    SciTech Connect (OSTI)

    Koniges, A E; Masters, N D; Fisher, A C; Anderson, R W; Eder, D C; Benson, D; Kaiser, T B; Gunney, B T; Wang, P; Maddox, B R; Hansen, J F; Kalantar, D H; Dixit, P; Jarmakani, H; Meyers, M A

    2009-03-03T23:59:59.000Z

    Fragmentation is a fundamental material process that naturally spans spatial scales from microscopic to macroscopic. We developed a mathematical framework using an innovative combination of hierarchical material modeling (HMM) and adaptive mesh refinement (AMR) to connect the continuum to microstructural regimes. This framework has been implemented in a new multi-physics, multi-scale, 3D simulation code, NIF ALE-AMR. New multi-material volume fraction and interface reconstruction algorithms were developed for this new code, which is leading the world effort in hydrodynamic simulations that combine AMR with ALE (Arbitrary Lagrangian-Eulerian) techniques. The interface reconstruction algorithm is also used to produce fragments following material failure. In general, the material strength and failure models have history vector components that must be advected along with other properties of the mesh during remap stage of the ALE hydrodynamics. The fragmentation models are validated against an electromagnetically driven expanding ring experiment and dedicated laser-based fragmentation experiments conducted at the Jupiter Laser Facility. As part of the exit plan, the NIF ALE-AMR code was applied to a number of fragmentation problems of interest to the National Ignition Facility (NIF). One example shows the added benefit of multi-material ALE-AMR that relaxes the requirement that material boundaries must be along mesh boundaries.

  14. An Attempt to Calibrate and Validate a Simple Ductile Failure Model Against Axial-Torsion Experiments on Al 6061-T651.

    SciTech Connect (OSTI)

    Reedlunn, Benjamin; Lu, Wei-Yang [Sandia National Laboratories, Livermore, CA

    2015-01-01T23:59:59.000Z

    This report details a work in progress. We have attempted to calibrate and validate a Von Mises plasticity model with the Johnson-Cook failure criterion ( Johnson & Cook , 1985 ) against a set of experiments on various specimens of Al 6061-T651. As will be shown, the effort was not successful, despite considerable attention to detail. When the model was com- pared against axial-torsion experiments on tubes, it over predicted failure by 3 x in tension, and never predicted failure in torsion, even when the tube was twisted by 4 x further than the experiment. While this result is unfortunate, it is not surprising. Ductile failure is not well understood. In future work, we will explore whether more sophisticated material mod- els of plasticity and failure will improve the predictions. Selecting the appropriate advanced material model and interpreting the results of said model are not trivial exercises, so it is worthwhile to fully investigate the behavior of a simple plasticity model before moving on to an anisotropic yield surface or a similarly complicated model.

  15. Material model library for explicit numerical codes

    SciTech Connect (OSTI)

    Hofmann, R.; Dial, B.W.

    1982-08-01T23:59:59.000Z

    A material model logic structure has been developed which is useful for most explicit finite-difference and explicit finite-element Lagrange computer codes. This structure has been implemented and tested in the STEALTH codes to provide an example for researchers who wish to implement it in generically similar codes. In parallel with these models, material parameter libraries have been created for the implemented models for materials which are often needed in DoD applications.

  16. ATOMISTIC MODELING OF ELECTRODE MATERIALS

    Broader source: Energy.gov (indexed) [DOE]

    life and rate * High cost of electrode materials * Project lead: Venkat Srinivasan (LBNL) * Marca Doeff (LBNL): Al-substituted layered Li-TM-O 2 * Phil Ross (LBNL) and Gerbrand...

  17. Atomistic Modeling of Electrode Materials

    Broader source: Energy.gov (indexed) [DOE]

    and rate * High cost of electrode materials * Project lead: John Newman * Marca Doeff (LBNL) on layered Li-TM-O 2 for effects of Al substitution * Phil Ross (LBNL) on nano-LiFePO...

  18. Failure Mode Analysis of a Proposed Manipulator-based Hazardous Material Retrieval System

    E-Print Network [OSTI]

    Cavallaro, Joseph R.

    for manipulators involved in hazardous waste management operations, where failure could be both expensive (supplied by Westinghouse Hanford Company), a design report on the Hose Management Arm (HMA),1 modes of a robot manipulator-based system for tank waste retrieval. The advantages and limitations

  19. Cohesive zone modeling of dynamic failure in homogeneous and functionally

    E-Print Network [OSTI]

    Paulino, Glaucio H.

    . For example, a functionally graded armor composite with a tailored ceramic to metal through-thickness gradient and shapes, as well as by interchanging the roles of reinforcement and matrix (base) materials combines the beneficial effects of ceramics (e.g., hardness) and metals (e.g., toughness) in the same

  20. Advancing Material Models for Automotive Forming Simulations

    SciTech Connect (OSTI)

    Vegter, H.; An, Y.; Horn, C.H.L.J. ten; Atzema, E.H.; Roelofsen, M.E. [Corus Research Development and Technology, PO Box 10000, 1970 CA IJmuiden (Netherlands)

    2005-08-05T23:59:59.000Z

    Simulations in automotive industry need more advanced material models to achieve highly reliable forming and springback predictions. Conventional material models implemented in the FEM-simulation models are not capable to describe the plastic material behaviour during monotonic strain paths with sufficient accuracy. Recently, ESI and Corus co-operate on the implementation of an advanced material model in the FEM-code PAMSTAMP 2G. This applies to the strain hardening model, the influence of strain rate, and the description of the yield locus in these models. A subsequent challenge is the description of the material after a change of strain path.The use of advanced high strength steels in the automotive industry requires a description of plastic material behaviour of multiphase steels. The simplest variant is dual phase steel consisting of a ferritic and a martensitic phase. Multiphase materials also contain a bainitic phase in addition to the ferritic and martensitic phase. More physical descriptions of strain hardening than simple fitted Ludwik/Nadai curves are necessary.Methods to predict plastic behaviour of single-phase materials use a simple dislocation interaction model based on the formed cells structures only. At Corus, a new method is proposed to predict plastic behaviour of multiphase materials have to take hard phases into account, which deform less easily. The resulting deformation gradients create geometrically necessary dislocations. Additional micro-structural information such as morphology and size of hard phase particles or grains is necessary to derive the strain hardening models for this type of materials.Measurements available from the Numisheet benchmarks allow these models to be validated. At Corus, additional measured values are available from cross-die tests. This laboratory test can attain critical deformations by large variations in blank size and processing conditions. The tests are a powerful tool in optimising forming simulations prior to larger scale industrial validation.

  1. New Computer Model Pinpoints Prime Materials for Carbon Capture

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Model Pinpoints Prime Materials for Carbon Capture New Computer Model Pinpoints Prime Materials for Carbon Capture July 17, 2012 | Tags: Dirac, Energy Technologies, Materials...

  2. A Bayesian Bivariate Failure Time Regression Model by Paul Damien

    E-Print Network [OSTI]

    West, Mike

    . In engineering studies, reliability is defined as the probability that the system has not failed at time t . The reliability of a system using the model in (1) is given by R(t) = P (T 1 ? t; T 2 ? t) = exp(\\Gammaâ??t)[1 using Markov Chain Monte Carlo methods. Keywords: Gumbel Distribution, Gibbs Sampling, Correlation

  3. A Reliability Model for Nonhomogeneous Redundant Software Versions with Correlated Failures

    E-Print Network [OSTI]

    Gutjahr, Walter

    A Reliability Model for Nonhomogeneous Redundant Software Versions with Correlated Failures Walter Abstract: The article develops a technique for computing the reliability (1) of a recovery block with fault{version programming, soft- ware reliability. 1 Introduction An important issue in the evaluation and optimization

  4. A Novel Virtual Age Reliability Model for Time-to-Failure Prediction

    E-Print Network [OSTI]

    Kuzmanov, Georgi

    counts, devices approaching physical feature size limits and nuclear plant comparable power densityA Novel Virtual Age Reliability Model for Time-to-Failure Prediction Yao Wang, Sorin Cotofana their relatively short operating lifetime. To overcome the MTTF weakness, this paper proposes a novel virtual age

  5. A Simple GSPN for Modeling Common Mode Failures in Critical Infrastructures

    E-Print Network [OSTI]

    Krings, Axel W.

    A Simple GSPN for Modeling Common Mode Failures in Critical Infrastructures Axel Krings and Paul@cs.uidaho.edu) Abstract It is now apparent that our nation's infrastructures and essential utilities have been optimized independent, survivable software control systems for automated regulation of critical infrastructures like

  6. Deformation rate effects on failure modes of open-cell Al foams and textile cellular materials

    E-Print Network [OSTI]

    Barthelat, Francois

    September 2005 Abstract The compressive behavior of open-cell aluminum alloy foam and stainless steel woven: Metallic cellular materials; Dynamic compression; Aluminum foams; Woven textile lattice 0020-7683/$ - see are of attracting interest for a variety of automotive, locomotive, marine, and aerospace applications (Gibson

  7. Combining Modeling Methodologies for Improved Understanding of Smart Material Characteristics

    E-Print Network [OSTI]

    Lindner, Douglas K.

    Combining Modeling Methodologies for Improved Understanding of Smart Material Characteristics Material Systems and Structures February 2, 1998 ABSTRACT Smart materials are complex materials performance capabilities but the synergistic response of the smart material and companion structure. Behavior

  8. Scientists use world's fastest computer to model materials under...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials under extreme conditions Scientists use world's fastest computer to model materials under extreme conditions Materials scientists are for the first time attempting to...

  9. Theory and Modeling of Weakly Bound/Physisorbed Materials for...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Theory and Modeling of Weakly BoundPhysisorbed Materials for Hydrogen Storage Theory and Modeling of Weakly BoundPhysisorbed Materials for Hydrogen Storage Presentation on the...

  10. DYNAMIC FAILURE OF METALLIC CELLULAR MATERIALS S. LEE and H.D. ESPINOSA

    E-Print Network [OSTI]

    Espinosa, Horacio D.

    interest in the protection design in automotive, locomotive, naval structures, and aerospace. Metallic not observe any rate dependency for the crashing stress of aluminum foams. These discrepancies from different within the specimen at very high strain rates. A model for shock waves in closed cell aluminum foams

  11. NUMERICAL MODELING OF CATHODE CONTACT MATERIAL DENSIFICATION

    SciTech Connect (OSTI)

    Koeppel, Brian J.; Liu, Wenning N.; Stephens, Elizabeth V.; Khaleel, Mohammad A.

    2011-11-01T23:59:59.000Z

    Numerical modeling was used to simulate the constrained sintering process of the cathode contact layer during assembly of solid oxide fuel cells (SOFCs). A finite element model based on the continuum theory for sintering of porous bodies was developed and used to investigate candidate low-temperature cathode contact materials. Constitutive parameters for various contact materials under investigation were estimated from dilatometry screening tests, and the influence of processing time, processing temperature, initial grain size, and applied compressive stress on the free sintering response was predicted for selected candidate materials. The densification behavior and generated stresses within a 5-cell planar SOFC stack during sintering, high temperature operation, and room temperature shutdown were predicted. Insufficient constrained densification was observed in the stack at the proposed heat treatment, but beneficial effects of reduced grain size, compressive stack preload, and reduced thermal expansion coefficient on the contact layer densification and stresses were observed.

  12. Modelling Inter-Industry Material Flows

    E-Print Network [OSTI]

    ............................................................................................ 4 3.1.2. Life-cycle Analysis. The development of energy-materials-economic models arose out of the need for tools to aid the development, capable of representing complex systems and interactions in a comprehensive and concise way. However

  13. Scaling of structural failure

    SciTech Connect (OSTI)

    Bazant, Z.P. [Northwestern Univ., Evanston, IL (United States); Chen, Er-Ping [Sandia National Lab., Albuquerque, NM (United States)

    1997-01-01T23:59:59.000Z

    This article attempts to review the progress achieved in the understanding of scaling and size effect in the failure of structures. Particular emphasis is placed on quasibrittle materials for which the size effect is complicated. Attention is focused on three main types of size effects, namely the statistical size effect due to randomness of strength, the energy release size effect, and the possible size effect due to fractality of fracture or microcracks. Definitive conclusions on the applicability of these theories are drawn. Subsequently, the article discusses the application of the known size effect law for the measurement of material fracture properties, and the modeling of the size effect by the cohesive crack model, nonlocal finite element models and discrete element models. Extensions to compression failure and to the rate-dependent material behavior are also outlined. The damage constitutive law needed for describing a microcracked material in the fracture process zone is discussed. Various applications to quasibrittle materials, including concrete, sea ice, fiber composites, rocks and ceramics are presented.

  14. Irreversible Thermodynamics and Smart Materials Systems Modelling. Example of

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Irreversible Thermodynamics and Smart Materials Systems Modelling. Example of Magnetic Shape Memory mechanisms in smart materials. This procedure is applied to Magnetic Shape Memory Alloys actuators of complex active materials for smart systems. Keywords: Smart material systems, Actuator design

  15. Comparison of Hyperelastic Models for Granular Materials

    SciTech Connect (OSTI)

    Paul W. Humrickhouse; J. Phil Sharpe; Michael L. Corradini

    2010-01-01T23:59:59.000Z

    Three recently proposed hyperelastic models for granular materials are compared with experiment data. Though all three are formulated to give elastic moduli that are power law functions of the mean stress, they have rather different dependencies on individual stresses, and generally differ from well established experimental forms. Predicted static stress distributions are in qualitative agreement with experiments, but do not differ greatly from isotropic linear elasticity, and similarly fail to account for variability in experiment data that presumably occurs due to a preparation dependence of granular materials.

  16. Failure of semiclassical models to describe resistivity of nanometric, polycrystalline tungsten films

    SciTech Connect (OSTI)

    Choi, Dooho [Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (United States); Korea Railroad Research Institute, 360-1 Woulam, Uiwang, Kyunggi 437-757 (Korea, Republic of); Liu, Xuan [Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (United States); Schelling, Patrick K. [Advanced Materials Processing and Analysis Center and Department of Physics, University of Central Florida, 4000 Central Florida Boulevard, Orlando, Florida 32816 (United States); Coffey, Kevin R. [Department of Materials Science and Engineering, University of Central Florida, 4000 Central Florida Boulevard, Orlando, Florida 32816 (United States); Barmak, Katayun [Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (United States); Department of Applied Physics and Applied Mathematics, Columbia University, 500 West 120th Street, New York, New York 10027 (United States)

    2014-03-14T23:59:59.000Z

    The impact of electron scattering at surfaces and grain boundaries in nanometric polycrystalline tungsten (W) films was studied. A series of polycrystalline W films ranging in thickness from 10 to 310?nm and lateral grain size from 74 to 133?nm were prepared on thermally oxidized Si. The Fuchs-Sondheimer surface-scattering model and Mayadas-Shatzkes grain-boundary scattering model were employed for quantitative analyses. Predictions from the theoretical models were found to deviate systematically from the experimental data. Possible reasons for the failure of the theoretical models to describe the experimental data are explored. Finally, a discussion of the crucial features lacking from existing models is presented, along with possible avenues for improving the models to result in better agreement with experimental data.

  17. Materials Theory, Modeling and Simulation | ORNL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Characterization Materials Theory and Simulation Quantum Monte Carlo Density Functional Theory Monte Carlo Ab Initio Molecular Dynamics Chemical and Materials Theory...

  18. A mid-layer model for human reliability analysis : understanding the cognitive causes of human failure events.

    SciTech Connect (OSTI)

    Shen, Song-Hua (US Nuclear Regulatory Commission, Washington, DC); Chang, James Y. H. (US Nuclear Regulatory Commission, Washington, DC); Boring,Ronald L. (Idaho National Laboratory, Idaho Falls, ID); Whaley, April M. (Idaho National Laboratory, Idaho Falls, ID); Lois, Erasmia (US Nuclear Regulatory Commission, Washington, DC); Hendrickson, Stacey M. Langfitt; Oxstrand, Johanna H. (Vattenfall Ringhals AB, Varobacka, Sweden); Forester, John Alan; Kelly, Dana L. (Idaho National Laboratory, Idaho Falls, ID); Mosleh, Ali (University of Maryland, College Park, MD)

    2010-03-01T23:59:59.000Z

    The Office of Nuclear Regulatory Research (RES) at the US Nuclear Regulatory Commission (USNRC) is sponsoring work in response to a Staff Requirements Memorandum (SRM) directing an effort to establish a single human reliability analysis (HRA) method for the agency or guidance for the use of multiple methods. As part of this effort an attempt to develop a comprehensive HRA qualitative approach is being pursued. This paper presents a draft of the method's middle layer, a part of the qualitative analysis phase that links failure mechanisms to performance shaping factors. Starting with a Crew Response Tree (CRT) that has identified human failure events, analysts identify potential failure mechanisms using the mid-layer model. The mid-layer model presented in this paper traces the identification of the failure mechanisms using the Information-Diagnosis/Decision-Action (IDA) model and cognitive models from the psychological literature. Each failure mechanism is grouped according to a phase of IDA. Under each phase of IDA, the cognitive models help identify the relevant performance shaping factors for the failure mechanism. The use of IDA and cognitive models can be traced through fault trees, which provide a detailed complement to the CRT.

  19. Life Cycle Modeling of Propulsion Materials

    Broader source: Energy.gov (indexed) [DOE]

    propulsion materials manufacturing technologies with an emphasis on aluminum, magnesium, titanium, and ceramics * Advanced propulsion materials' potential in heavy-duty...

  20. Patient-specific modeling of cardiac electromechanics in dyssynchronous heart failure

    E-Print Network [OSTI]

    Shin, Jun Seob

    2009-01-01T23:59:59.000Z

    1.3 Congestive Heart1.1: Longitudinal cross-section of the heart . . . . . . .Classification of heart failure . . . . . . . . . . . .

  1. Computational modeling of materials processing and processes

    SciTech Connect (OSTI)

    Lowe, T.C.; Zhu, Yuntian; Bingert, J.F. [and others

    1998-12-31T23:59:59.000Z

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Anisotropic mechanical properties of densified BSCCO powders are of paramount importance during thermo-mechanical processing of superconducting tapes and wires. Maximum current transport requires high relative density and a high degree of alignment of the single crystal planes of the BSCCO. Unfortunately this configuration causes high stresses that can lead to cracking, and thus reduce the density, and the conductive properties of the tape. The current work develops a micromechanical material mode to model is calibrated and compared to experimental results, and then employed to analyze the effects of initial texture and confinement pressure and shear strains in the core of oxide powder-in-tube (OPIT) processed tapes are calculated by finite-element analysis. The calculated deformations were then applied as boundary conditions to the micromechanical model. Our calculated results were used to interpret a set of prototypical rolling experiments. 11 refs., 5 figs.

  2. Theory and models of material erosion and lifetime during plasma instabilities in a tokamak environment.

    SciTech Connect (OSTI)

    Hassanein, A.; Konkashbaev, I.

    1999-11-08T23:59:59.000Z

    Surface and structural damage to plasma-facing components (PFCs) due to the frequent loss of plasma confinement remains a serious problem for the tokamak reactor concept. The deposited plasma energy causes significant surface erosion, possible structural failure, and frequent plasma contamination. Surface damage consists of vaporization, spallation, and liquid splatter of metallic materials. Structural damage includes large temperature increases in structural materials and at the interfaces between surface coatings and structural members. To evaluate the lifetimes of plasma-facing materials and nearby components and to predict the various forms of damage that they experience, comprehensive models (contained in the HEIGHTS computer simulation package) are developed, integrated self-consistently, and enhanced. Splashing mechanisms such as bubble boiling and various liquid magnetohydrodynamic instabilities and brittle destruction mechanisms of nonmelting materials are being examined. The design requirements and implications of plasma-facing and nearby components are discussed, along with recommendations to mitigate and reduce the effects of plasma instabilities on reactor components.

  3. Multiscale Modeling and Homogenization of Composite Materials

    E-Print Network [OSTI]

    Mseis, George

    2010-01-01T23:59:59.000Z

    Schematics of fiber composite . . . . . . . . . .of long fiber sic/ti composite materials. Comput. Methodsof Fibre-reinforced composites. Wiley, 4th edition, 2002. [

  4. Preprint December 2003 A Loading-Dependent Model of Probabilistic Cascading Failure

    E-Print Network [OSTI]

    people (U.S.-Canada Power Sys- tem Outage Task Force 2003). The vital importance of the electrical Benjamin A. Carreras David E. Newman Abstract: Large blackouts of electric power transmission systems failure yields a power law region in the distribution of the number of failures similar

  5. Non-destructive Failure Analysis and Modeling of Encapsulated Miniature SMD Ceramic Chip Capacitors under Thermal and

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Non-destructive Failure Analysis and Modeling of Encapsulated Miniature SMD Ceramic Chip Capacitors under Thermal and Mechanical Loading B. Wunderle1 , T. Braun1 , D. May1 , A. Mazloum1 , M. Bouazza1 , H-layer ceramic chip ca- pacitors as integrated passive in e. g. system in package applications needs methods

  6. Materials Science & Metallurgy Master of Philosophy, Materials Modelling, Course MP6, Kinetics and Microstructure Modelling, H. K. D. H. Bhadeshia

    E-Print Network [OSTI]

    Cambridge, University of

    Materials Science & Metallurgy Master of Philosophy, Materials Modelling, Course MP6, Kinetics in metallurgy. To form a complete design­technology, it is consequently necessary to re- sort to careful

  7. Materials Science & Metallurgy Master of Philosophy, Materials Modelling, Course MP10, Process Modelling, H. K. D. H. Bhadeshia

    E-Print Network [OSTI]

    Cambridge, University of

    Materials Science & Metallurgy Master of Philosophy, Materials Modelling, Course MP10, Process.­E. Svensson. The metallurgy of the welded joint can be categorised into two major regions, the fusion zone

  8. Validation of Material Models for Automotive Carbon Fiber Composite...

    Broader source: Energy.gov (indexed) [DOE]

    Validation of Material Models for Automotive Carbon Fiber Composite Structures (VMM) Libby Berger (General Motors), Omar Faruque (Ford) Co-Principal Investigators US Automotive...

  9. Water Transport in PEM Fuel Cells: Advanced Modeling, Material...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Testing, and Design Optimization Water Transport in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing, and Design Optimization This presentation, which focuses on...

  10. Water Transport in PEM Fuel Cells: Advanced Modeling, Material...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Testing and Design Optimization Water Transport in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing and Design Optimization Part of a 100 million fuel cell award...

  11. Fusion materials modeling: Challenges and opportunities

    E-Print Network [OSTI]

    Wirth, B. D.

    The plasma facing components, first wall, and blanket systems of future tokamak-based fusion power plants arguably represent the single greatest materials engineering challenge of all time. Indeed, the United States National ...

  12. Modelling and characterisation of porous materials.

    E-Print Network [OSTI]

    Alsayednoor, Jafar

    2013-01-01T23:59:59.000Z

    ??Porous materials possessing random microstructures exist in both organic (e.g. polymer foam, bone) and in-organic (e.g. silica aerogels) forms. Foams and aerogels are two such… (more)

  13. FLUID FLOW MODELING OF RESIN TRANSFER MOLDING FOR COMPOSITE MATERIAL WIND TURBINE BLADE STRUCTURES

    E-Print Network [OSTI]

    FLUID FLOW MODELING OF RESIN TRANSFER MOLDING FOR COMPOSITE MATERIAL WIND TURBINE BLADE STRUCTURES.............................................................................................................7 Composite Materials...................................................................................................7 Material Properties

  14. December 6, 1995 A MODEL FOR MATERIALS DATABASES

    E-Print Network [OSTI]

    Wiederhold, Gio

    believe are the most closely related to future development of materials database management. Broadly advanced materials are unsuitable. 5. Interfaces provided by existing database management systemsDecember 6, 1995 A MODEL FOR MATERIALS DATABASES Gio Wiederhold Laie Caindec John McCarthy Ken

  15. The tunneling model of laser-induced ionization and its failure at low frequencies

    E-Print Network [OSTI]

    H. R. Reiss

    2014-05-11T23:59:59.000Z

    The tunneling model of ionization applies only to longitudinal fields: quasistatic electric fields that do not propagate. Laser fields are transverse: plane wave fields that possess the ability to propagate. Although there is an approximate connection between the effects of longitudinal and transverse fields in a useful range of frequencies, that equivalence fails completely at very low frequencies. Insight into this breakdown is given by an examination of radiation pressure, which is a unique transverse-field effect whose relative importance increases rapidly as the frequency declines. Radiation pressure can be ascribed to photon momentum, which does not exist for longitudinal fields. Two major consequences are that the near-universal acceptance of a static electric field as the zero frequency limit of a laser field is not correct; and that the numerical solution of the dipole-approximate Schr\\"{o}dinger equation for laser effects is inapplicable as the frequency declines. These problems occur because the magnetic component of the laser field is very important at low frequencies, and hence the dipole approximation is not valid. Some experiments already exist that demonstrate the failure of tunneling concepts at low frequencies.

  16. Detecting and modeling cement failure in high pressure/ high temperature wells using finite-element method

    E-Print Network [OSTI]

    Shahri, Mehdi Abbaszadeh

    2006-04-12T23:59:59.000Z

    conditions and are investigated simultaneously to more accurately predict cement failure. The results of this study show the relevant dependency of stress principles with temperature and pressure. These results clarify the deformation caused by any...

  17. Materials Theory, Modeling and Simulation | ORNL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces andMapping the Nanoscale LandscapeImports 5.90Materials Porous Materials

  18. Materialized community ground models for large-scale earthquake simulation

    E-Print Network [OSTI]

    Shewchuk, Jonathan

    Materialized community ground models for large-scale earthquake simulation Steven W. Schlosser to ground motion sim- ulations, in which ground model datasets are fully materi- alized into octress stored as a service techniques in which scientific computation and storage services become more tightly intertwined. 1

  19. Digital control systems in nuclear power plants: Failure information, modeling concepts, and applications. Revision 1

    SciTech Connect (OSTI)

    Galyean, W.J.

    1993-06-23T23:59:59.000Z

    This report briefly describes some current applications of advanced computerized digital display and control systems at US commercial nuclear power plants and presents the results of a literature search that was made to gather information on the reliability of these systems. Both hardware and software reliability were addressed in this review. Only limited failure rate information was found, with the chemical process industry being the primary source of information on hardware failure rates and expert opinion the primary source for software failure rates. Safety-grade digital control systems are typically installed on a functional like-for-like basis, replacing older analog systems without substantially changing interactions with other plant systems. Future work includes performing a limited probabilistic risk assessment of a representative DCS to assess its risk significance.

  20. Digital control systems in nuclear power plants: Failure information, modeling concepts, and applications

    SciTech Connect (OSTI)

    Galyean, W.J.

    1993-06-23T23:59:59.000Z

    This report briefly describes some current applications of advanced computerized digital display and control systems at US commercial nuclear power plants and presents the results of a literature search that was made to gather information on the reliability of these systems. Both hardware and software reliability were addressed in this review. Only limited failure rate information was found, with the chemical process industry being the primary source of information on hardware failure rates and expert opinion the primary source for software failure rates. Safety-grade digital control systems are typically installed on a functional like-for-like basis, replacing older analog systems without substantially changing interactions with other plant systems. Future work includes performing a limited probabilistic risk assessment of a representative DCS to assess its risk significance.

  1. Cascading Dynamics and Mitigation Assessment in Power System Disturbances via a Hidden Failure Model

    E-Print Network [OSTI]

    and control strategy. The sensitivity of power-law behavior with respect to each of these parameters; Protective Relaying hidden failures; Blackout mitigation Introduction An overriding factor in power system] in spite of technological progress and huge investments on the system reliability and security. Although

  2. Combining Functional Modelling and Qualitative Fault Propagation to Enable Failure Mode Analysis of

    E-Print Network [OSTI]

    Snooke, Neal

    of Software Systems Neal Snooke and Jonathan Bell 1 Abstract. Failure Modes and Effects Analysis (FMEA- ware, and qualitative fault propagation, enables automated Software FMEA (SFMEA). The result is a broad in extending FMEA into the soft- ware itself [3, 14, 6, 8] however there has been little progress in developing

  3. Using Failure Models for Controlling Data Availability in Wireless Sensor Networks

    E-Print Network [OSTI]

    Kravets, Robin

    life-cycle, batteries are charged and nodes have just been tested, so the failure probability of a node how the solution provided by Pirrus achieves good performance with a sustainable computational cost, such as depletion of the available battery energy, hardware defects in the node and harsh environmental conditions

  4. A continuum constitutive model for amorphous metallic materials

    E-Print Network [OSTI]

    Su, Cheng, Ph. D. Massachusetts Institute of Technology

    2007-01-01T23:59:59.000Z

    A finite-deformation, Coulomb-Mohr type constitutive theory for the elastic-viscoplastic response of pressure-sensitive and plastically-dilatant isotropic materials has been developed. The constitutive model has been ...

  5. Electrochemical Modeling of LMR-NMC Materials and Electrodes

    Broader source: Energy.gov (indexed) [DOE]

    Modeling of LMR-NMC Materials and Electrodes Project ID: ES189 Presented by Dennis Dees Voltage Fade Team and CAMP Facility Team 2014 DOE Vehicle Technologies Office Annual Merit...

  6. Atomistic modeling of nanowires, small-scale fatigue damage in cast magnesium, and materials for MEMS.

    SciTech Connect (OSTI)

    Dunn, Martin L. (University of Colorado, Boulder, CO); Talmage, Mellisa J. (University of Colorado, Boulder, CO); McDowell, David L., 1956- (,-Georgia Institute of Technology, Atlanta, GA); West, Neil (University of Colorado, Boulder, CO); Gullett, Philip Michael (Mississippi State University , MS); Miller, David C. (University of Colorado, Boulder, CO); Spark, Kevin (University of Colorado, Boulder, CO); Diao, Jiankuai (University of Colorado, Boulder, CO); Horstemeyer, Mark F. (Mississippi State University , MS); Zimmerman, Jonathan A.; Gall, K (Georgia Institute of Technology, Atlanta, GA)

    2006-10-01T23:59:59.000Z

    Lightweight and miniaturized weapon systems are driving the use of new materials in design such as microscale materials and ultra low-density metallic materials. Reliable design of future weapon components and systems demands a thorough understanding of the deformation modes in these materials that comprise the components and a robust methodology to predict their performance during service or storage. Traditional continuum models of material deformation and failure are not easily extended to these new materials unless microstructural characteristics are included in the formulation. For example, in LIGA Ni and Al-Si thin films, the physical size is on the order of microns, a scale approaching key microstructural features. For a new potential structural material, cast Mg offers a high stiffness-to-weight ratio, but the microstructural heterogeneity at various scales requires a structure-property continuum model. Processes occurring at the nanoscale and microscale develop certain structures that drive material behavior. The objective of the work presented in this report was to understand material characteristics in relation to mechanical properties at the nanoscale and microscale in these promising new material systems. Research was conducted primarily at the University of Colorado at Boulder to employ tightly coupled experimentation and simulation to study damage at various material size scales under monotonic and cyclic loading conditions. Experimental characterization of nano/micro damage will be accomplished by novel techniques such as in-situ environmental scanning electron microscopy (ESEM), 1 MeV transmission electron microscopy (TEM), and atomic force microscopy (AFM). New simulations to support experimental efforts will include modified embedded atom method (MEAM) atomistic simulations at the nanoscale and single crystal micromechanical finite element simulations. This report summarizes the major research and development accomplishments for the LDRD project titled 'Atomistic Modeling of Nanowires, Small-scale Fatigue Damage in Cast Magnesium, and Materials for MEMS'. This project supported a strategic partnership between Sandia National Laboratories and the University of Colorado at Boulder by providing funding for the lead author, Ken Gall, and his students, while he was a member of the University of Colorado faculty.

  7. A multifluid mix model with material strength effects

    SciTech Connect (OSTI)

    Chang, C. H. [Los Alamos National Laboratory; Scannapieco, A. J. [Los Alamos National Laboratory

    2012-04-23T23:59:59.000Z

    We present a new multifluid mix model. Its features include material strength effects and pressure and temperature nonequilibrium between mixing materials. It is applicable to both interpenetration and demixing of immiscible fluids and diffusion of miscible fluids. The presented model exhibits the appropriate smooth transition in mathematical form as the mixture evolves from multiphase to molecular mixing, extending its applicability to the intermediate stages in which both types of mixing are present. Virtual mass force and momentum exchange have been generalized for heterogeneous multimaterial mixtures. The compression work has been extended so that the resulting species energy equations are consistent with the pressure force and material strength.

  8. Development of a failure prediction model for heat-treated glass

    E-Print Network [OSTI]

    Ditsworth, Jay Morgan

    1992-01-01T23:59:59.000Z

    . Lynn Beason Little heat-treated glass research has been performed to date on laterally loaded heat-treated glass plates, and nearly all published research has been empirical rather than analytic in nature. Therefore, current heat-treated glass design... VI CONCLUSION . 60 REFERENCES 62 APPENDICES Page APPENDIX A - VILD'S STATISTICAL ANALYSIS OF THE TRADITIONAL DESIGN METHOD. . . . . . . . . APPENDIX B ? SAMPLE DATA SHEET APPENDIX C - TEST SERIES I, II, AND III FAILURE LOADS CORRESPONDING TO A...

  9. Material-modeling and structural-mechanics aspects

    E-Print Network [OSTI]

    Grujicic, Mica

    Material-modeling and structural-mechanics aspects of the traumatic brain injury problem M for causing traumatic brain injury. Design/methodology/approach ­ Two levels of blast peak overpressure were computational investigation of impact on a human skull/brain assembly. Keywords Brain, Injuries, Modeling

  10. A physically-based abrasive wear model for composite materials

    SciTech Connect (OSTI)

    Lee, Gun Y.; Dharan, C.K.H.; Ritchie, Robert O.

    2001-05-01T23:59:59.000Z

    A simple physically-based model for the abrasive wear of composite materials is presented based on the mechanics and mechanisms associated with sliding wear in soft (ductile) matrix composites containing hard (brittle) reinforcement particles. The model is based on the assumption that any portion of the reinforcement that is removed as wear debris cannot contribute to the wear resistance of the matrix material. The size of this non-contributing portion of the reinforcement is estimated by modeling the three primary wear mechanisms, specifically plowing, interfacial cracking and particle removal. Critical variables describing the role of the reinforcement, such as its relative size and the nature of the matrix/reinforcement interface, are characterized by a single contribution coefficient, C. Predictions are compared with the results of experimental two-body (pin-on drum) abrasive wear tests performed on a model aluminum particulate-reinforced epoxy matrix composite material.

  11. Air-Cooled Stack Freeze Tolerance Freeze Failure Modes and Freeze Tolerance Strategies for GenDriveTM Material Handling Application Systems and Stacks Final Scientific Report

    SciTech Connect (OSTI)

    Hancock, David, W.

    2012-02-14T23:59:59.000Z

    Air-cooled stack technology offers the potential for a simpler system architecture (versus liquid-cooled) for applications below 4 kilowatts. The combined cooling and cathode air allows for a reduction in part count and hence a lower cost solution. However, efficient heat rejection challenges escalate as power and ambient temperature increase. For applications in ambient temperatures below freezing, the air-cooled approach has additional challenges associated with not overcooling the fuel cell stack. The focus of this project was freeze tolerance while maintaining all other stack and system requirements. Through this project, Plug Power advanced the state of the art in technology for air-cooled PEM fuel cell stacks and related GenDrive material handling application fuel cell systems. This was accomplished through a collaborative work plan to improve freeze tolerance and mitigate freeze-thaw effect failure modes within innovative material handling equipment fuel cell systems designed for use in freezer forklift applications. Freeze tolerance remains an area where additional research and understanding can help fuel cells to become commercially viable. This project evaluated both stack level and system level solutions to improve fuel cell stack freeze tolerance. At this time, the most cost effective solutions are at the system level. The freeze mitigation strategies developed over the course of this project could be used to drive fuel cell commercialization. The fuel cell system studied in this project was Plug Power's commercially available GenDrive platform providing battery replacement for equipment in the material handling industry. The fuel cell stacks were Ballard's commercially available FCvelocity 9SSL (9SSL) liquid-cooled PEM fuel cell stack and FCvelocity 1020ACS (Mk1020) air-cooled PEM fuel cell stack.

  12. Application Of A New Semi-Empirical Model For Forming Limit Prediction Of Sheet Material Including Superposed Loads Of Bending And Shearing

    SciTech Connect (OSTI)

    Held, Christian [Hochschul Institute Neckarsulm, Gottlieb-Daimler-Strasse 40, 74172 Neckarsulm (Germany); Liewald, Mathias; Schleich, Ralf [Institute for Metal Forming Technology, Universitaet Stuttgart, Stuttgart (Germany); Sindel, Manfred [AUDI AG, Neckarsulm (Germany)

    2010-06-15T23:59:59.000Z

    The use of lightweight materials offers substantial strength and weight advantages in car body design. Unfortunately such kinds of sheet material are more susceptible to wrinkling, spring back and fracture during press shop operations. For characterization of capability of sheet material dedicated to deep drawing processes in the automotive industry, mainly Forming Limit Diagrams (FLD) are used. However, new investigations at the Institute for Metal Forming Technology have shown that High Strength Steel Sheet Material and Aluminum Alloys show increased formability in case of bending loads are superposed to stretching loads. Likewise, by superposing shearing on in plane uniaxial or biaxial tension formability changes because of materials crystallographic texture. Such mixed stress and strain conditions including bending and shearing effects can occur in deep-drawing processes of complex car body parts as well as subsequent forming operations like flanging. But changes in formability cannot be described by using the conventional FLC. Hence, for purpose of improvement of failure prediction in numerical simulation codes significant failure criteria for these strain conditions are missing. Considering such aspects in defining suitable failure criteria which is easy to implement into FEA a new semi-empirical model has been developed considering the effect of bending and shearing in sheet metals formability. This failure criterion consists of the combination of the so called cFLC (combined Forming Limit Curve), which considers superposed bending load conditions and the SFLC (Shear Forming Limit Curve), which again includes the effect of shearing on sheet metal's formability.

  13. Modeling thermal/chemical/mechanical response of energetic materials

    SciTech Connect (OSTI)

    Baer, M.R.; Hobbs, M.L.; Gross, R.J. [and others

    1995-07-01T23:59:59.000Z

    An overview of modeling at Sandia National Laboratories is presented which describes coupled thermal, chemical and mechanical response of energetic materials. This modeling addresses cookoff scenarios for safety assessment studies in systems containing energetic materials. Foundation work is discussed which establishes a method for incorporating chemistry and mechanics into multidimensional analysis. Finite element analysis offers the capabilities to simultaneously resolve reactive heat transfer and structural mechanics in complex geometries. Nonlinear conduction heat transfer, with multiple step finite-rate chemistry, is resolved using a thermal finite element code. Rate equations are solved element-by-element using a modified matrix-free stiff solver This finite element software was developed for the simulation of systems requiring large numbers of finite elements. An iterative implicit scheme, based on the conjugate gradient method, is used and a hemi-cube algorithm is employed for the determination of view factors in surface-to-surface radiation transfer The critical link between the reactive heat transfer and mechanics is the introduction of an appropriate constitutive material model providing a stress-strain relationship for quasi-static mechanics analysis. This model is formally derived from bubble nucleation theory, and parameter variations of critical model parameters indicate that a small degree of decomposition leads to significant mechanical response. Coupled thermal/chemical/mechanical analysis is presented which simulates experiments designed to probe cookoff thermal-mechanical response of energetic materials.

  14. Compendium of Material Composition Data for Radiation Transport Modeling

    SciTech Connect (OSTI)

    McConn, Ronald J.; Gesh, Christopher J.; Pagh, Richard T.; Rucker, Robert A.; Williams III, Robert

    2011-03-04T23:59:59.000Z

    Introduction Meaningful simulations of radiation transport applications require realistic definitions of material composition and densities. When seeking that information for applications in fields such as homeland security, radiation shielding and protection, and criticality safety, researchers usually encounter a variety of materials for which elemental compositions are not readily available or densities are not defined. Publication of the Compendium of Material Composition Data for Radiation Transport Modeling, Revision 0, in 2006 was the first step toward mitigating this problem. Revision 0 of this document listed 121 materials, selected mostly from the combined personal libraries of staff at the Pacific Northwest National Laboratory (PNNL), and thus had a scope that was recognized at the time to be limited. Nevertheless, its creation did provide a well-referenced source of some unique or hard-to-define material data in a format that could be used directly in radiation transport calculations being performed at PNNL. Moreover, having a single common set of material definitions also helped to standardize at least one aspect of the various modeling efforts across the laboratory by providing separate researchers the ability to compare different model results using a common basis of materials. The authors of the 2006 compendium understood that, depending on its use and feedback, the compendium would need to be revised to correct errors or inconsistencies in the data for the original 121 materials, as well as to increase (per users suggestions) the number of materials listed. This 2010 revision of the compendium has accomplished both of those objectives. The most obvious change is the increased number of materials from 121 to 372. The not-so-obvious change is the mechanism used to produce the data listed here. The data listed in the 2006 document were compiled, evaluated, entered, and error-checked by a group of individuals essentially by hand, providing no library file or mechanism for revising the data in a consistent and traceable manner. The authors of this revision have addressed that problem by first compiling all of the information (i.e., numbers and references) for all the materials into a single database, maintained at PNNL, that was then used as the basis for this document.

  15. Modelling of the ultrasonic propagation in polycrystalline materials

    E-Print Network [OSTI]

    Boyer, Edmond

    . Jenson Commissariat `a l'´energie atomique, Centre de Saclay - PC120, 91191 Gif-Sur-Yvette, France lili designing new NDE methods. Modeling work has been underway at CEA-LIST in the software CIVA to describe such as a polycrystalline material. The objective is to develop new simulation tools based on metallurgical data input

  16. A network model of parametric working memory. Supplementary Material

    E-Print Network [OSTI]

    Brody, Carlos

    obeys the current balance equation: CM dVi dt = -gL [Vi - VL]-gESE,i [Vi - VE]-gISI,i [Vi - VIA network model of parametric working memory. Supplementary Material Paul Miller1 , Carlos D Brody2

  17. A method for estimating common cause failure probability and model parameters : the inverse stress-strength interference (ISSI) technique

    E-Print Network [OSTI]

    Guey, Ching Ning

    1984-01-01T23:59:59.000Z

    In this study, an alternative for the analysis of common cause failures (CCFs) is investigated. The method studied consists of using the Licensee Event Report (LER) data to get single component failure probability and using ...

  18. A 4D geometrical modeling of a material aging

    E-Print Network [OSTI]

    A. Chudnovsky; S. Preston

    2006-04-16T23:59:59.000Z

    4-dim intrinsic (material) Riemannian metric $G$ of the material 4-D space-time continuum $P$ is utilized as the characteristic of the aging processes developing in the material. Manifested through variation of basic material characteristics such as density, moduli of elasticity, yield stress, strength, and toughness., the aging process is modeled as the evolution of the metric $G$ (most importantly of its time component $G_{00}$) of the material space-time $P$ embedded into 4-D Newtonian space-time with Euclidean metric.\\par The evolutional equation for metric $G$ is derived by the classical variational approach. Construction of a Lagrangian for an aging elastic media and the derivation of a system of coupled elastostatic and aging equations constitute the central part of the work. The external and internal balance laws associated with symmetries of material and physical space-time geometries are briefly reviewed from a new viewpoint presented in the paper. Examples of the stress relaxation and creep of a homogeneous rod, cold drawing, and chemical degradation in a tubing are discussed.

  19. Large scale molecular dynamics modeling of materials fabrication processes

    SciTech Connect (OSTI)

    Belak, J.; Glosli, J.N.; Boercker, D.B.; Stowers, I.F.

    1994-02-01T23:59:59.000Z

    An atomistic molecular dynamics model of materials fabrication processes is presented. Several material removal processes are shown to be within the domain of this simulation method. Results are presented for orthogonal cutting of copper and silicon and for crack propagation in silica glass. Both copper and silicon show ductile behavior, but the atomistic mechanisms that allow this behavior are significantly different in the two cases. The copper chip remains crystalline while the silicon chip transforms into an amorphous state. The critical stress for crack propagation in silica glass was found to be in reasonable agreement with experiment and a novel stick-slip phenomenon was observed.

  20. A Probabilistic Model for the Dynamics of Cascading Failures and Blackouts in Power Grids

    E-Print Network [OSTI]

    Hayat, Majeed M.

    @unm.edu, mammoli@unm.edu, hayat@ece.unm.edu Department of Electrical and Computer Engineering, University of New Mexico, Albuquerque, NM, USA Department of Mechanical Engineering, University of New Mexico, Albuquerque, NM, USA Center for High Technology Materials, University of New Mexico, Albuquerque, NM, USA

  1. Seismic Performance, Modeling, and Failure Assessment of Reinforced Concrete Shear Wall Buildings

    E-Print Network [OSTI]

    Tuna, Zeynep

    2012-01-01T23:59:59.000Z

    J.W. , (2009). Testing and Reinforced Concrete Coupling2010). "Testing and Modeling of Reinforced Concrete Couplingscale testing of four-story reinforced concrete and post-

  2. Arctic sea ice modeling with the material-point method.

    SciTech Connect (OSTI)

    Peterson, Kara J.; Bochev, Pavel Blagoveston

    2010-04-01T23:59:59.000Z

    Arctic sea ice plays an important role in global climate by reflecting solar radiation and insulating the ocean from the atmosphere. Due to feedback effects, the Arctic sea ice cover is changing rapidly. To accurately model this change, high-resolution calculations must incorporate: (1) annual cycle of growth and melt due to radiative forcing; (2) mechanical deformation due to surface winds, ocean currents and Coriolis forces; and (3) localized effects of leads and ridges. We have demonstrated a new mathematical algorithm for solving the sea ice governing equations using the material-point method with an elastic-decohesive constitutive model. An initial comparison with the LANL CICE code indicates that the ice edge is sharper using Materials-Point Method (MPM), but that many of the overall features are similar.

  3. Modeling shear failure and permeability enhancement due to coupled Thermal-Hydrological-Mechanical processes in Enhanced Geothermal Reservoirs

    SciTech Connect (OSTI)

    Kelkar, Sharad [Los Alamos National Laboratory

    2011-01-01T23:59:59.000Z

    The connectivity and accessible surface area of flowing fractures, whether natural or man-made, is possibly the single most important factor, after temperature, which determines the feasibility of an Enhanced Geothermal System (EGS). Rock deformation and in-situ stress changes induced by injected fluids can lead to shear failure on preexisting fractures which can generate microseismic events, and also enhance the permeability and accessible surface area of the geothermal formation. Hence, the ability to accurately model the coupled thermal-hydrologic-mechanical (THM) processes in fractured geological formations is critical in effective EGS reservoir development and management strategies. The locations of the microseismic events can serve as indicators of the zones of enhanced permeability, thus providing vital information for verification of the coupled THM models. We will describe a general purpose computational code, FEHM, developed for this purpose, that models coupled THM processes during multiphase fluid flow and transport in fractured porous media. The code incorporates several models of fracture aperture and stress behavior combined with permeability relationships. We provide field scale examples of applications to geothermal systems to demonstrate the utility of the method.

  4. Failure modes at room and elevated temperatures. Technical report

    SciTech Connect (OSTI)

    Braun, L.M.

    1995-04-01T23:59:59.000Z

    Successful development of reliable ceramic composites will depend on an understanding of matrix cracking and damage mechanisms in these materials. Therefore, the objective of the Failure Models subtask is to investigate failure and damage mechanisms in fiber reinforced ceramic composites. Issues such as how fiber coatings, the fiber/matrix interface, residual stresses, and fiber volume fraction affect frictional stresses, fiber debonding, fiber pull-out and failure modes will be examined. The effect of these microstructural parameters on matrix crack initiation, propagation and damage will also be determined. The resulting observations and measurements data will be used to develop theoretical models for damage mechanisms in fiber reinforced composites. This report presents results concerning the effect of temperature on the failure modes of continuous fiber ceramic composites performed during the last quarter of FY 1993 and FY 1994. The Raman stress measurements and calculations were performed during the last quarter of FY 1994 and the first quarter of FY 1995.

  5. Evaluation of a semi-implicit numerical algorithm for a rate-dependent ductile failure model.

    SciTech Connect (OSTI)

    Zocher, M. A. (Marvin Anthony); Zuo, Q. K. (Qiuhai K.); Mason, T. A. (Thomas A.)

    2002-09-01T23:59:59.000Z

    A survey conducted in the mid-80's revealed that the mathematical descriptions of ductile fracture tended to apply to either tensile tests or spa11 tests. The objective behind the development of the TEPLA was then a unification of these disparate phenomena into a single model.

  6. Model-based Failure Modes and Effects Analysis of Neal Snooke 1

    E-Print Network [OSTI]

    Snooke, Neal

    embedded software developers who are already familiar with the benefits of FMEA analysis. Several au- thors discuss experiences of performing manual FMEA of software however there has been no attempt at automating of software and the success of model based automated FMEA for hardware. 1 Introduction The notion of Software

  7. Micromechanical Damage Models for Continuous Fiber Reinforced Composite Materials

    E-Print Network [OSTI]

    Wu, Yi

    2013-01-01T23:59:59.000Z

    plastic matrix composite, Material and Design, 31: Zhou,scheme for composite materials, International Journal ofelastic energy of materials with misfitting inclusions, Acta

  8. RECERTIFICATION OF THE MODEL 9977 RADIOACTIVE MATERIAL PACKAGING

    SciTech Connect (OSTI)

    Abramczyk, G.; Bellamy, S.; Loftin, B.; Nathan, S.

    2013-06-05T23:59:59.000Z

    The Model 9977 Packaging was initially issued a Certificate of Compliance (CoC) by the Department of Energy’s Office of Environmental Management (DOE-EM) for the transportation of radioactive material (RAM) in the Fall of 2007. This first CoC was for a single radioactive material and two packing configurations. In the five years since that time, seven Addendums have been written to the Safety Analysis Report for Packaging (SARP) and five Letter Amendments have been written that have authorized either new RAM contents or packing configurations, or both. This paper will discuss the process of updating the 9977 SARP to include all the contents and configurations, including the addition of a new content, and its submittal for recertification.

  9. Modeling Creep-Fatigue-Environment Interactions in Steam Turbine Rotor Materials for Advanced Ultra-supercritical Coal Power Plants

    SciTech Connect (OSTI)

    Shen, Chen

    2014-01-20T23:59:59.000Z

    The goal of this project is to model creep-fatigue-environment interactions in steam turbine rotor materials for advanced ultra-supercritical (A-USC) coal power Alloy 282 plants, to develop and demonstrate computational algorithms for alloy property predictions, and to determine and model key mechanisms that contribute to the damages caused by creep-fatigue-environment interactions. The nickel based Alloy 282 is selected for this project because it is one of the leading candidate materials for the high temperature/pressure section of an A-USC steam turbine. The methods developed in the project are expected to be applicable to other metal alloys in similar steam/oxidation environments. The major developments are: ? failure mechanism and microstructural characterization ? atomistic and first principles modeling of crack tip oxygen embrittlement ? modeling of gamma prime microstructures and mesoscale microstructure-defect interactions ? microstructure and damage-based creep prediction ? multi-scale crack growth modeling considering oxidation, viscoplasticity and fatigue The technology developed in this project is expected to enable more accurate prediction of long service life of advanced alloys for A-USC power plants, and provide faster and more effective materials design, development, and implementation than current state-of-the-art computational and experimental methods. This document is a final technical report for the project, covering efforts conducted from January 2011 to January 2014.

  10. Concrete Material Models Concrete_1: Concrete Model with No Tensile Strength

    E-Print Network [OSTI]

    Filippou, Filip C.

    Concrete Material Models Concrete_1: Concrete Model with No Tensile Strength INPUT Concrete_1, matID ¢f fc cu u, , ,e e0 Definitions (Fig. 1): fc : concrete compressive strength at 28 days (compression is negative) A0 : concrete strain at maximum strength (compression is negative) fcu : concrete crushing

  11. Materials Science and Engineering A, 2011, 528(1-2): p. 7596 7605 High strain rate compressive response ofsyntactic foams: trends in mechanical properties and failure mechanisms

    E-Print Network [OSTI]

    Gupta, Nikhil

    comprising hollow particles dispersed in a matrix material. Available studies on high strain rate compressive with respect to the material composition. Syntactic foams reinforced with micro- and nano-sized fibers are a class of porous materials in which thin-walled hollow particles are dispersed in a matrix material

  12. Report for the ASC CSSE L2 Milestone (4873) - Demonstration of Local Failure Local Recovery Resilient Programming Model.

    SciTech Connect (OSTI)

    Heroux, Michael A.; Teranishi, Keita [Sandia National Laboratories, Livermore, CA

    2014-06-01T23:59:59.000Z

    Recovery from process loss during the execution of a distributed memory parallel application is presently achieved by restarting the program, typically from a checkpoint file. Future computer system trends indicate that the size of data to checkpoint, the lack of improvement in parallel file system performance and the increase in process failure rates will lead to situations where checkpoint restart becomes infeasible. In this report we describe and prototype the use of a new application level resilient computing model that manages persistent storage of local state for each process such that, if a process fails, recovery can be performed locally without requiring access to a global checkpoint file. LFLR provides application developers with an ability to recover locally and continue application execution when a process is lost. This report discusses what features are required from the hardware, OS and runtime layers, and what approaches application developers might use in the design of future codes, including a demonstration of LFLR-enabled MiniFE code from the Matenvo mini-application suite.

  13. Materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2 MAG LAB REPORTS Volume 18 No. 1 CONDENSED MATTER SCIENCE Technique development, graphene, magnetism & magnetic materials, topological insulators, quantum fl uids & solids,...

  14. Micromechanical Modeling of Multiphysical Behavior of Smart Materials Using the Variational

    E-Print Network [OSTI]

    Yu, Wenbin

    Micromechanical Modeling of Multiphysical Behavior of Smart Materials Using the Variational to predict the effective properties as well as the local fields of periodic smart materials responsive modeling scheme. To treat general microstructure of smart materials, we implemented this model using

  15. Stochastic Simulation Model for the 3D Morphology of Composite Materials in Li-Ion Batteries

    E-Print Network [OSTI]

    Schmidt, Volker

    Stochastic Simulation Model for the 3D Morphology of Composite Materials in Li-Ion Batteries Ralf of composite materials used in Li-ion batteries. In this paper, we develop a stochastic simulation model in 3D, Stochastic Simulation Model, Structural Analysis, Marked Point Process, Germ-Grain Model, Model Fitting

  16. Modeling the thermoelectric properties of bulk and nanocomposite thermoelectric materials

    E-Print Network [OSTI]

    Minnich, Austin (Austin Jerome)

    2008-01-01T23:59:59.000Z

    Thermoelectric materials are materials which are capable of converting heat directly into electricity. They have long been used in specialized fields where high reliability is needed, such as space power generation. Recently, ...

  17. Abduction Compared with Negation by Failure

    E-Print Network [OSTI]

    Koehn, Philipp

    Abduction Compared with Negation by Failure K. Eshghi * Hewlett Packard Laboratories programming can be extended to include abduction with integrity constraints. In the resulting extension for negation by failure, which generalises the stable model semantics of negation by failure. The abductive

  18. Modifications in the AA5083 Johnson-Cook Material Model for Use in Friction Stir Welding

    E-Print Network [OSTI]

    Grujicic, Mica

    Modifications in the AA5083 Johnson-Cook Material Model for Use in Friction Stir Welding, material microstructure and properties in friction stir welding welds of AA5083 (a non welding, Johnson-Cook material model 1. Introduction In this study, an attempt is made to modify

  19. Thermomechanical Constitutive Modeling of Viscoelastic Materials undergoing Degradation

    E-Print Network [OSTI]

    Karra, Satish

    2012-07-16T23:59:59.000Z

    . . . . . . . . . . . . . . . . . . . . . . . 17 2. Constitutive assumptions . . . . . . . . . . . . . . . . 20 3. Reduction of the model to one dimensional Burg- ers? model . . . . . . . . . . . . . . . . . . . . . . . . . 24 D. Model 2... . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 1. Preliminaries . . . . . . . . . . . . . . . . . . . . . . . 27 2. Constitutive assumptions . . . . . . . . . . . . . . . . 30 3. Reduction of the model to one dimensional Burg- ers? model . . . . . . . . . . . . . . . . . . . . . . . . . 32...

  20. Evaluation of the numerical stability and sensitivity to material parameter variations for several unified constitutive models

    E-Print Network [OSTI]

    Imbrie, Peter Kenneth

    1985-01-01T23:59:59.000Z

    Material Constants Used In Bodner's Model For Hastelloy-X at 1800' F . Naterial Constants Used In Walker's Model For Hastelloy-X at 1800' F . Material Constants Used In Krieg's Model For Hastelloy-X at 1800 F . Material Constants Used In Miller...'s Model For Hastelloy-X at 1800' F . Page 18 26 30 35 LIST OF FIGURES Fi gure Plots Used to Obtain Material Parameters For Bodner's Model . Page T6 Back Stress and True Stress-Strain Curve Used in Walker's Theory. Plot Used to Determine...

  1. Application for managing model-based material properties for simulation-based engineering

    DOE Patents [OSTI]

    Hoffman, Edward L. (Alameda, CA)

    2009-03-03T23:59:59.000Z

    An application for generating a property set associated with a constitutive model of a material includes a first program module adapted to receive test data associated with the material and to extract loading conditions from the test data. A material model driver is adapted to receive the loading conditions and a property set and operable in response to the loading conditions and the property set to generate a model response for the material. A numerical optimization module is adapted to receive the test data and the model response and operable in response to the test data and the model response to generate the property set.

  2. Fire Retardant Polymer Nanocomposites: Materials Design and Thermal Degradation Modeling.

    E-Print Network [OSTI]

    Zhuge, Jinfeng

    2012-01-01T23:59:59.000Z

    ??Compared to conventional materials, polymer matrix composites (PMCs) have a number of attractive properties, including light weight, easiness of installation, potential to lower system-level cost,… (more)

  3. Materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recovery challenge fund LasDubey selectedContract Research Material

  4. Identification of material parameters for continuum modeling of phase transformations in multicomponent systems

    E-Print Network [OSTI]

    Umantsev, Alexander

    Identification of material parameters for continuum modeling of phase transformations called order pa- rameters, which take on specified values in the bulk phases. If the transformation

  5. Nanotechnology Nanotechnology comprises measurement, design, modeling and fabrication of materials and systems at the atomic scale.

    E-Print Network [OSTI]

    Glowinski, Roland

    Nanotechnology Nanotechnology comprises measurement, design, modeling and fabrication of materials are able to customize their education by specializing in areas such as nanotechnology, computational

  6. Advanced Modeling and Materials in Kraft Pulp Mills

    SciTech Connect (OSTI)

    Keiser, J.R.; Gorog, J.P.

    2002-05-15T23:59:59.000Z

    This CRADA provided technical support to the Weyerhaeuser Company on a number of issues related to the performance and/or selection of materials at a number of locations in a pulp and paper mill. The studies related primarily to components for black liquor recovery boilers, but some effort was directed toward black liquor gasifiers and rolls for paper machines. The purpose of this CRADA was to assist Weyerhaeuser in the evaluation of materials exposed in various paper mill environments and to provide direction in the selection of alternate materials, when appropriate.

  7. Use of UHPC in Bridge Structures: Material Modeling and Design

    E-Print Network [OSTI]

    Gunes, Oguz

    Ultra-high-performance concrete (UHPC) is a promising new class of concrete material that is likely to make a significant contribution to addressing the challenges associated with the load capacity, durability, sustainability, ...

  8. First Principles Modeling for Research and Design of New Materials

    E-Print Network [OSTI]

    Ceder, Gerbrand

    First principles computation can be used to investigate an design materials in ways that can not be achieved with experimental means. We show how computations can be used to rapidly capture the essential physics that ...

  9. TAMCN: a tool for aggregate modeling of civil nuclear materials

    E-Print Network [OSTI]

    Watson, Aaron Michael

    2002-01-01T23:59:59.000Z

    involved in the creation, storage, and utilization of potentially destructive nuclear material. Western Europe and Japan, namely France, Belgium, the United Kingdom, Germany, Switzerland, and Japan, were chosen as a starting point because the issues...

  10. Solar Thermal Reactor Materials Characterization

    SciTech Connect (OSTI)

    Lichty, P. R.; Scott, A. M.; Perkins, C. M.; Bingham, C.; Weimer, A. W.

    2008-03-01T23:59:59.000Z

    Current research into hydrogen production through high temperature metal oxide water splitting cycles has created a need for robust high temperature materials. Such cycles are further enhanced by the use of concentrated solar energy as a power source. However, samples subjected to concentrated solar radiation exhibited lifetimes much shorter than expected. Characterization of the power and flux distributions representative of the High Flux Solar Furnace(HFSF) at the National Renewable Energy Laboratory(NREL) were compared to ray trace modeling of the facility. In addition, samples of candidate reactor materials were thermally cycled at the HFSF and tensile failure testing was performed to quantify material degradation. Thermal cycling tests have been completed on super alloy Haynes 214 samples and results indicate that maximum temperature plays a significant role in reduction of strength. The number of cycles was too small to establish long term failure trends for this material due to the high ductility of the material.

  11. Light water reactor lower head failure analysis

    SciTech Connect (OSTI)

    Rempe, J.L.; Chavez, S.A.; Thinnes, G.L. [EG and G Idaho, Inc., Idaho Falls, ID (United States)] [and others

    1993-10-01T23:59:59.000Z

    This document presents the results from a US Nuclear Regulatory Commission-sponsored research program to investigate the mode and timing of vessel lower head failure. Major objectives of the analysis were to identify plausible failure mechanisms and to develop a method for determining which failure mode would occur first in different light water reactor designs and accident conditions. Failure mechanisms, such as tube ejection, tube rupture, global vessel failure, and localized vessel creep rupture, were studied. Newly developed models and existing models were applied to predict which failure mechanism would occur first in various severe accident scenarios. So that a broader range of conditions could be considered simultaneously, calculations relied heavily on models with closed-form or simplified numerical solution techniques. Finite element techniques-were employed for analytical model verification and examining more detailed phenomena. High-temperature creep and tensile data were obtained for predicting vessel and penetration structural response.

  12. A review of macroscopic ductile failure criteria.

    SciTech Connect (OSTI)

    Corona, Edmundo; Reedlunn, Benjamin

    2013-09-01T23:59:59.000Z

    The objective of this work was to describe several of the ductile failure criteria com- monly used to solve practical problems. The following failure models were considered: equivalent plastic strain, equivalent plastic strain in tension, maximum shear, Mohr- Coulomb, Wellman's tearing parameter, Johnson-Cook and BCJ MEM. The document presents the main characteristics of each failure model as well as sample failure predic- tions for simple proportional loading stress histories in three dimensions and in plane stress. Plasticity calculations prior to failure were conducted with a simple, linear hardening, J2 plasticity model. The resulting failure envelopes were plotted in prin- cipal stress space and plastic strain space, where the dependence on stress triaxiality and Lode angle are clearly visible. This information may help analysts select a ductile fracture model for a practical problem and help interpret analysis results.

  13. Cu-Bi as a Model System For Liquid Phase Sintered Thermal Interface Management Materials

    E-Print Network [OSTI]

    Collins, Gary S.

    relates electrical resistivity to thermal conductivity for materials where electrons are principleCu-Bi as a Model System For Liquid Phase Sintered Thermal Interface Management Materials P to produce composite materials. A high melting phase (HMP) and low melting phase (LMP) are mixed

  14. Wear 252 (2002) 322331 A physically-based abrasive wear model for composite materials

    E-Print Network [OSTI]

    Ritchie, Robert

    Wear 252 (2002) 322­331 A physically-based abrasive wear model for composite materials Gun Y. Leea 2001 Abstract A simple physically-based model for the abrasive wear of composite materials is presented based on the mechanics and mechanisms associated with sliding wear in soft (ductile)- matrix composites

  15. Phenomenological modelling of viscoplasticity Mechanics of Materials Laboratory, Rensselaer Polytechnic Institute, Troy, NY 12180-3590,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    331 Phenomenological modelling of viscoplasticity E. Krempl Mechanics of Materials Laboratory. - The essentials of phenomenological modeling of metal deformation behavior at small strain are introduced together interpreted from a materials science viewpoint are re-analyzed from a phenomenological point of view

  16. Modeling - Scale-Bridging Simulations Active Materials in Li...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    & Publications Microscale Electrode Design Using Coupled Kinetic, Thermal and Mechanical Modeling Overview of the Batteries for Advanced Transportation Technologies (BATT)...

  17. Surface Finish Modeling in Micromilling of Biocompatible Materials

    E-Print Network [OSTI]

    Berestovskyi, Dmytro V

    2013-06-05T23:59:59.000Z

    the requirements listed above. Computer controlled micromilling on a high speed machine system in minimum quantity lubrication was used to remove most materials and define a channel pattern. Microchannels were machined with ball end mills of diameters from Ø152?m...

  18. Multi-length scale computational derivation of Kevlar material model

    E-Print Network [OSTI]

    Grujicic, Mica

    in various protective systems whose main requirement is a high level of penetration resistance against high kinetic energy projectiles (e.g., bullets, mine, IED, or turbine fragments, etc.). Their high mass-efficiency (i.e., mass normalized performance) makes these materials and structures particularly suitable

  19. Abstract--The analysis of follow-up data from patients suffering from heart failure is a difficult task, due to the complex and multifactorial nature of this pathology. In this paper, we present a coupled model, integrating a pulsatile heart into a model

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Abstract--The analysis of follow-up data from patients suffering from heart failure a coupled model, integrating a pulsatile heart into a model of the short to long-term regulations decompensated heart failure episode on a patient undergoing cardiac resynchronization therapy. Index Terms

  20. Waste Form Degradation Model Integration for Engineered Materials...

    Broader source: Energy.gov (indexed) [DOE]

    models of glass waste form and metallic waste form degradation and the major corrosion products expected from these processes (e.g., gel and secondary phases such as clays...

  1. Utilization of Smart Materials and Predictive Modeling to Integrate Intracellular Dynamics with Cell Biomechanics and Collective Tissue Behavior

    E-Print Network [OSTI]

    Mather, Patrick T.

    Utilization of Smart Materials and Predictive Modeling to Integrate Intracellular Dynamics important structures inside cells. New "smart" material will be used to trigger changes to cell movement Medical University Control of Cell Polarization by Smart Material Substrates Multiscale Imaging Multiscale

  2. Numerical simulation of detonation failure in nitromethane

    SciTech Connect (OSTI)

    Kipp, M.E.; Nunziato, J.W.

    1981-01-01T23:59:59.000Z

    Detonation failure in the homogeneous liquid explosive nitromethane has been observed experimentally in a wide variety of confining geometries. However, numerical simulation of these failure situations with a wave propagation code has been essentially non-existent due to the large differences between the critical diameter and the length of the reaction zone - characteristic dimensions which differ by about two orders of magnitude. This inability to spatially resolve both the reaction zone and geometries of significant size has led us to propose a new numerical technique, based on the stability criterion for rate-type material models, in which only temporal resolution of the reaction zone is required. Using an improved model for nitromethane, we have carried out a series of two-dimensional calculations which illustrate the utility of the present approach in predicting a wide range of experimental observations. Of particular computational significance is the removal of the difficulty requiring spatial resolution of the reaction zone, so that problems of practical size can be analyzed with existing computer capabilities.

  3. An enhanced Lemaitre model formulation for materials processing damage computation

    E-Print Network [OSTI]

    Boyer, Edmond

    are presented and discussed to deal with complex multiaxial configurations ­ such as multi-stages bulk forming loading, involving crack closure effects. - Simple parameters identification: whatever the damage model used, the identification of damage parameters is an important issue. Most of the time

  4. International Conference "Computational Modeling and Simulation of Materials" Sicily 2004

    E-Print Network [OSTI]

    Webb, Roger P.

    how the deformation of a silicon surface caused by a high energy C60 impact can eject a large cages. But also the use of C60 ions in secondary mass spectrometry (SIMS) as a probing beam is showing in collaboration with the University of Karlsruhe, the simulation models have been verified for both low energy

  5. Dielectric breakdown model for conductor-loaded and insulator-loaded composite materials P. Bergero,1

    E-Print Network [OSTI]

    Peruani, Fernando

    Dielectric breakdown model for conductor-loaded and insulator-loaded composite materials P. Bergero strength is highly desirable, and in the past years composite materials such as resin matrix filled- tors, and composites containing carbon black and titanium dioxide have recently been tested

  6. NONLINEAR ANALYSIS OF RUBBER-BASED POLYMERIC MATERIALS WITH THERMAL RELAXATION MODELS

    E-Print Network [OSTI]

    Melnik, Roderick

    NONLINEAR ANALYSIS OF RUBBER-BASED POLYMERIC MATERIALS WITH THERMAL RELAXATION MODELS R. V. N of the material and their close connection with the effect of thermal relaxation time can be best appreciated (phonons). A relaxation time appears naturally as the characteristic of thermal resistance in the solid

  7. Vehicle Technologies Office Merit Review 2014: Validation of Material Models for Automotive Carbon Fiber Composite Structures

    Broader source: Energy.gov [DOE]

    Presentation given by General Motors at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about validation of material models...

  8. Development and numerical implementation of nonlinear viscoelastic-viscoplastic model for asphalt materials

    E-Print Network [OSTI]

    Huang, Chien-Wei

    2009-05-15T23:59:59.000Z

    pavements is illustrated using finite element simulations. The constitutive model developed in this study can describe the behavior of asphalt materials (asphalt binder, asphalt mastic and mixtures) under various testing conditions. This study also achieved...

  9. First-Principles Models of Properties of LMR-NMC Materials

    Broader source: Energy.gov (indexed) [DOE]

    First-Principles Models of Properties of LMR-NMC Materials Project Id: ES193 R. Benedek, H. Iddir DOE Vehicle Technologies Program Annual Merit Review Arlington, VA May 13 - 17,...

  10. Modeling a solar energy collector with an integrated phase-change material

    E-Print Network [OSTI]

    Guerra, Alexander Adrian

    2009-01-01T23:59:59.000Z

    In this thesis, a finite-element computer model was created to simulate a solar air heater with an integrated-phase change material. The commercially available finite element package ADINA-Fluid was used to generate the ...

  11. Material characterization of high-voltage lithium-ion battery models for crashworthiness analysis

    E-Print Network [OSTI]

    Meier, Joseph D. (Joseph David)

    2013-01-01T23:59:59.000Z

    A three-phased study of the material properties and post-impact behavior of prismatic pouch lithium-ion battery cells was conducted to refine computational finite element models and explore the mechanisms of thermal runaway ...

  12. The automatic generation of semantic annotations for didactic materials and the use of models in the material development to improve its reusability

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    The automatic generation of semantic annotations for didactic materials and the use of models.es, aedo@ia.inf.uc3m.es Abstract The didactic material reusability, understood as its capability to be used in the MD2 approach to automatically generate semantic annotations within the didactic material development

  13. Atomistic Modeling of Electrode Materials | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-Up fromDepartmentTie Ltd: Scope Change #1Impacts |ServicesAtomistic Modeling of Electrode

  14. Application of micromechanical models of ductile fracture initiation to reactor pressure vessel materials

    SciTech Connect (OSTI)

    Chaouadi, R.; Walle, E. van; Fabry, A.; Velde, J. van de [SCK-CEN, Mol (Belgium); Meester, P. de [KUL, Heverlee (Belgium). Metals and Materials Science Dept.

    1996-12-31T23:59:59.000Z

    The aim of the current study is the application of local micromechanical models to predict crack initiation in ductile materials. Two reactor pressure vessel materials have been selected for this study: JRQ IAEA monitor base metal (A533B Cl.1) and Doel-IV weld material. Charpy impact tests have been performed in both un-irradiated and irradiated conditions. In addition to standard tensile tests, notched tensile specimens have been tested. The upper shelf energy of the weld material remains almost un-affected by irradiation, whereas a decrease of 20% is detected for the base metal. Accordingly, the tensile properties of the weld material do not reveal a clear irradiation effect on the yield and ultimate stresses, this in contrast to the base material flow properties. The tensile tests have been analyzed in terms of micromechanical models. A good correlation is found between the standard tests and the micromechanical models, that are able to predict the ductile damage evolution in these materials. Additional information on the ductility behavior of these materials is revealed by this micromechanical analysis.

  15. Direct Modeling of Material Deposit and Identification of Energy Transfer in Gas Metal Arc Welding

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Direct Modeling of Material Deposit and Identification of Energy Transfer in Gas Metal Arc Welding sources for finite element simulation of gas metal arc welding (GMAW). Design for the modeling of metal deposition results in a direct calculation of the formation of the weld bead, without any

  16. Modeling of AA5083 Material-Microstructure Evolution During Butt Friction-Stir Welding

    E-Print Network [OSTI]

    Grujicic, Mica

    Modeling of AA5083 Material-Microstructure Evolution During Butt Friction-Stir Welding M. Grujicic yet a fairly comprehensive overview of the friction stir welding (FSW) process is provided-element procedure developed in our prior study. Particular attention is given to proper modeling of the welding work

  17. On models for viscoelastic fluid-like materials that are mechanically incompressible and

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    On models for viscoelastic fluid-like materials that are mechanically incompressible and thermally of the full Navier­Stokes­Fourier system. J. Math. Fluid Mech., 11:274­302, 2009 Mechanically incompressible;Viscoelastic fluids ­ Maxwell model F l lsld µm m Mechanical analogue: Spring ­ energy storage. Dashpot

  18. Great Lakes Spatially Distributed Watershed Model of Water and Materials Runoff Thomas E. Croley II

    E-Print Network [OSTI]

    Great Lakes Spatially Distributed Watershed Model of Water and Materials Runoff Thomas E. Croley II.S. Environmental Protection Agency (EPA) has identified contaminated sediments, urban runoff and storm sewers there are no integrated spatially distributed physically based watershed-scale hydrological/water quality models available

  19. Constitutive modeling of void shearing effect in ductile fracture of porous materials

    E-Print Network [OSTI]

    Xue, Liang

    * Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room 5 to describe plastic deformation for such type of materials. It has attracted a great deal of attention and various modifications to this model have been proposed. The constitutive equations of Gur- son-like model

  20. Modeling of quasistatic and dynamic load responses of filled viscoelastic materials

    E-Print Network [OSTI]

    are typically used for static finite element analysis (see [9]). The CRSC/Lord team worked, both theoreticallyModeling of quasi­static and dynamic load responses of filled viscoelastic materials H.T. Banks factors to the complications arising in the process of formulating models. Damping is highly complex

  1. MODELING OF TRIPLE JUNCTION A-SI SOLAR CELLS USING ASA: ANALYSIS OF DEVICE PERFORMANCE UNDER VARIOUS FAILURE SCENARIOS

    E-Print Network [OSTI]

    Deng, Xunming

    have experienced a significant increase in the recent years. Solar panels with triple- junction found. To assist the optimization of solar cell fabrication and cost-effective industrial photovoltaicMODELING OF TRIPLE JUNCTION A-SI SOLAR CELLS USING ASA: ANALYSIS OF DEVICE PERFORMANCE UNDER

  2. This paper focuses on solving the failure detection and isolation (FDI) problem by developing a model-based

    E-Print Network [OSTI]

    Taylor, James H.

    to a jacketed continuous stirred tank reactor (JCSTR). 1. Introduction The continuous and growing advances is exposed. In section 4 a novel calculation of the transformation matrix is proposed to improve isolation. In section 6, an example using a jacketed continuous stirred tank reactor (JCSTR) model is used to illustrate

  3. Contemporary heart failure management.

    E-Print Network [OSTI]

    Wasywich, Cara Anne

    2009-01-01T23:59:59.000Z

    ??The research presented within this thesis aims to add to the current knowledge regarding contemporary heart failure (HF) management. Chapter 2 describes a study collating… (more)

  4. SYNTHETIC SLING FAILURE - EVALUATIONS & RECOMMENDATIONS

    SciTech Connect (OSTI)

    MACKEY TC; HENDERSON CS

    2009-10-26T23:59:59.000Z

    The information and evaluations provided in this report were compiled to address the recurring problem of synthetic sling failure. As safety is the number one priority in all work aspects, a solution must be devised to prevent accidents from occurring. A total of thirteen cases regarding synthetic sling failure were evaluated in order to determine their causes, effects, and preventative measures. From the collected data, it was found that all cases in which the synthetic sling contacted the edge of its load resulted in sling failure. It is required that adequate synthetic sling protection devices be used to protect slings in any lift where the sling comes in direct contact with the edge or corner of its load. However, there are no consensus codes or standards stating the type, material, or purpose of the type of protective device used to protect the sling from being cut. Numerous industry standards and codes provide vague descriptions on how to protect synthetic slings. Without a clear, concise statement of how to protect synthetic slings, it is common for inadequate materials and sling protection devices to be used in an attempt to meet the intent of these requirements. The use of an inadequate sling protection device is the main cause of synthetic sling failure in all researched cases. Commercial sling protection devices come in many shapes and sizes, and have a variety of names, as well as advertised uses. 'Abrasion pads' and 'wear protectors' are two different names for products with the same intended purpose. There is no distinguishable way to determine the extent of sling protection which these devices will provide, or what specific scenarios they are made for. This creates room for error in a field where error is unacceptable. This report provides a recommended action for hoisting and rigging activities which require synthetic slings to contact a load, as well as recommended changes to industry standards which will benefit overall industry safety.

  5. Creep failure of a reactor pressure vessel lower head under severe accident conditions

    SciTech Connect (OSTI)

    Pilch, M.M.; Ludwigsen, J.S.; Chu, T.Y. [Sandia National Labs., Albuquerque, NM (United States); Rashid, Y.R. [Anatech, San Diego, CA (United States)

    1998-08-01T23:59:59.000Z

    A severe accident in a nuclear power plant could result in the relocation of large quantities of molten core material onto the lower head of he reactor pressure vessel (RPV). In the absence of inherent cooling mechanisms, failure of the RPV ultimately becomes possible under the combined effects of system pressure and the thermal heat-up of the lower head. Sandia National Laboratories has performed seven experiments at 1:5th scale simulating creep failure of a RPV lower head. This paper describes a modeling program that complements the experimental program. Analyses have been performed using the general-purpose finite-element code ABAQUS-5.6. In order to make ABAQUS solve the specific problem at hand, a material constitutive model that utilizes temperature dependent properties has been developed and attached to ABAQUS-executable through its UMAT utility. Analyses of the LHF-1 experiment predict instability-type failure. Predicted strains are delayed relative to the observed strain histories. Parametric variations on either the yield stress, creep rate, or both (within the range of material property data) can bring predictions into agreement with experiment. The analysis indicates that it is necessary to conduct material property tests on the actual material used in the experimental program. The constitutive model employed in the present analyses is the subject of a separate publication.

  6. Corrosion failures of austenitic stainless steel piping

    SciTech Connect (OSTI)

    Louthan, M.R. Jr.

    1993-10-01T23:59:59.000Z

    The safe and efficient operation of many chemical/industrial systems requires the continued integrity of the process piping; this is achieved through a complex series of interactions influenced by design, fabrication, construction, operation, inspection and lay-up requirements. Potential material-enviroment interactions are frequently, if evaluated at all, relegated to secondary considerations. This tendency virtually assures corrosion induced degradation of the process piping systems. Pitting, crevice attack, stress cracking, microbiologically influenced corrosion, intergranular attack and corrosion fatigue have caused leaks, cracks, failures and shutdown of numerous process systems. This paper uses the lessons learned from failure analysis to emphasize the importance of an integrated material program to system success. The necessity of continuing evaluation if also emphasized through examples of failures which were associated with materials-environment interactions caused by slight alterations of processes and/or systems.

  7. Data collection handbook to support modeling the impacts of radioactive material in soil

    SciTech Connect (OSTI)

    Yu, C.; Cheng, J.J.; Jones, L.G.; Wang, Y.Y.; Faillace, E. [Argonne National Lab., IL (United States). Environmental Assessment and Information Sciences Div.; Loureiro, C. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Escola de Engenharia; Chia, Y.P. [National Taiwan Univ., Taipei (Taiwan, Province of China). Dept. of Geology

    1993-04-01T23:59:59.000Z

    A pathway analysis computer code called RESRAD has been developed for implementing US Department of Energy Residual Radioactive Material Guidelines. Hydrogeological, meteorological, geochemical, geometrical (size, area, depth), and material-related (soil, concrete) parameters are used in the RESRAD code. This handbook discusses parameter definitions, typical ranges, variations, measurement methodologies, and input screen locations. Although this handbook was developed primarily to support the application of RESRAD, the discussions and values are valid for other model applications.

  8. Transient Heat and Material Flow Modeling of Friction Stir Processing of Magnesium Alloy using Threaded Tool

    SciTech Connect (OSTI)

    Yu, Zhenzhen [ORNL; Zhang, Wei [ORNL; Choo, Hahn [ORNL; Feng, Zhili [ORNL

    2012-01-01T23:59:59.000Z

    A three-dimensional transient computational fluid dynamics (CFD) model was developed to investigate the material flow and heat transfer during friction stir processing (FSP) in an AZ31B magnesium alloy. The material was assumed to be a non-Newtonian viscoplastic fluid, and the Zener-Hollomon parameter was used to describe the dependence of material viscosity on temperature and strain rate. The material constants used in the constitutive equation were determined experimentally from compression tests of the AZ31B Mg alloy under a wide range of strain rates and temperatures. A dynamic mesh method, combining both Lagrangian and Eulerian formulations, was used to capture the material flow induced by the movement of the threaded tool pin. Massless inert particles were embedded in the simulation domain to track the detailed history of material flow. The actual FSP was also carried out on a wrought Mg plate where temperature profiles were recorded by embedding thermocouples. The predicted transient temperature history was found to be consistent with that measured during FSP. Finally, the influence of the thread on the simulated results of thermal history and material flow was studied by comparing two models: one with threaded pin and the other with smooth pin surface.

  9. Model simulation and experiments of flow and mass transport through a nano-material gas filter

    SciTech Connect (OSTI)

    Yang, Xiaofan; Zheng, Zhongquan C.; Winecki, Slawomir; Eckels, Steve

    2013-11-01T23:59:59.000Z

    A computational model for evaluating the performance of nano-material packed-bed filters was developed. The porous effects of the momentum and mass transport within the filter bed were simulated. For the momentum transport, an extended Ergun-type model was employed and the energy loss (pressure drop) along the packed-bed was simulated and compared with measurement. For the mass transport, a bulk dsorption model was developed to study the adsorption process (breakthrough behavior). Various types of porous materials and gas flows were tested in the filter system where the mathematical models used in the porous substrate were implemented and validated by comparing with experimental data and analytical solutions under similar conditions. Good agreements were obtained between experiments and model predictions.

  10. Toward Multi-scale Modeling and simulation of conduction in heterogeneous materials.

    SciTech Connect (OSTI)

    Lechman, Jeremy B.; Battaile, Corbett Chandler.; Bolintineanu, Dan; Cooper, Marcia A.; Erikson, William W.; Foiles, Stephen M.; Kay, Jeffrey J [Sandia National Laboratories, Livermore, CA; Phinney, Leslie M.; Piekos, Edward S.; Specht, Paul Elliott; Wixom, Ryan R.; Yarrington, Cole

    2015-01-01T23:59:59.000Z

    This report summarizes a project in which the authors sought to develop and deploy: (i) experimental techniques to elucidate the complex, multiscale nature of thermal transport in particle-based materials; and (ii) modeling approaches to address current challenges in predicting performace variability of materials (e.g., identifying and characterizing physical- chemical processes and their couplings across multiple length and time scales, modeling infor- mation transfer between scales, and statically and dynamically resolving material structure and its evolution during manufacturing and device performance). Experimentally, several capabilities were sucessfully advanced. As discussed in Chapter 2 a flash diffusivity capabil- ity for measuring homogeneous thermal conductivity of pyrotechnic powders (and beyond) was advanced; leading to enhanced characterization of pyrotechnic materials and properties impacting component development. Chapter 4 describes sucess for the first time, although preliminary, in resolving thermal fields at speeds and spatial scales relevant to energetic components. Chapter 7 summarizes the first ever (as far as the authors know) application of TDTR to actual pyrotechnic materials. This is the first attempt to actually characterize these materials at the interfacial scale. On the modeling side, new capabilities in image processing of experimental microstructures and direct numerical simulation on complicated structures were advanced (see Chapters 3 and 5). In addition, modeling work described in Chapter 8 led to improved prediction of interface thermal conductance from first principles calculations. Toward the second point, for a model system of packed particles, significant headway was made in implementing numerical algorithms and collecting data to justify the approach in terms of highlighting the phenomena at play and pointing the way forward in de- veloping and informing the kind of modeling approach oringinally envisioned (see Chapter 6). In both cases much more remains to be accomplished.

  11. Models for mean bonding length, melting point and lattice thermal expansion of nanoparticle materials

    SciTech Connect (OSTI)

    Omar, M.S., E-mail: dr_m_s_omar@yahoo.com [Department of Physics, College of Science, University of Salahaddin-Erbil, Arbil, Kurdistan (Iraq)

    2012-11-15T23:59:59.000Z

    Graphical abstract: Three models are derived to explain the nanoparticles size dependence of mean bonding length, melting temperature and lattice thermal expansion applied on Sn, Si and Au. The following figures are shown as an example for Sn nanoparticles indicates hilly applicable models for nanoparticles radius larger than 3 nm. Highlights: ? A model for a size dependent mean bonding length is derived. ? The size dependent melting point of nanoparticles is modified. ? The bulk model for lattice thermal expansion is successfully used on nanoparticles. -- Abstract: A model, based on the ratio number of surface atoms to that of its internal, is derived to calculate the size dependence of lattice volume of nanoscaled materials. The model is applied to Si, Sn and Au nanoparticles. For Si, that the lattice volume is increases from 20 ?{sup 3} for bulk to 57 ?{sup 3} for a 2 nm size nanocrystals. A model, for calculating melting point of nanoscaled materials, is modified by considering the effect of lattice volume. A good approach of calculating size-dependent melting point begins from the bulk state down to about 2 nm diameter nanoparticle. Both values of lattice volume and melting point obtained for nanosized materials are used to calculate lattice thermal expansion by using a formula applicable for tetrahedral semiconductors. Results for Si, change from 3.7 × 10{sup ?6} K{sup ?1} for a bulk crystal down to a minimum value of 0.1 × 10{sup ?6} K{sup ?1} for a 6 nm diameter nanoparticle.

  12. A 3D Orthotropic Strain-Rate Dependent Elastic Damage Material Model.

    SciTech Connect (OSTI)

    English, Shawn Allen

    2014-09-01T23:59:59.000Z

    A three dimensional orthotropic elastic constitutive model with continuum damage and cohesive based fracture is implemented for a general polymer matrix composite lamina. The formulation assumes the possibility of distributed (continuum) damage followed b y localized damage. The current damage activation functions are simply partially interactive quadratic strain criteria . However, the code structure allows for changes in the functions without extraordinary effort. The material model formulation, implementation, characterization and use cases are presented.

  13. Finite Element Modeling of Rate-Dependent Ratcheting in Granular Materials

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Finite Element Modeling of Rate-Dependent Ratcheting in Granular Materials A. Karrech a,, A. Seibi thrust is the introduc- tion of the "Chicago" law in a continuum approach to account for the ratcheting or jointly with the ratcheting effect. Non-associated plasticity is adopted since the paper mainly targets

  14. Material Modeling and Development of a Realistic Dummy Testing Blast Induced Traumatic Brain Injury

    E-Print Network [OSTI]

    Farritor, Shane

    Material Modeling and Development of a Realistic Dummy Head for Testing Blast Induced Traumatic Brain Injury S. G. M. Hossain1, C. A. Nelson1, T. Boulet2, M. Arnoult2, L. Zhang2, A. Holmberg2, J. Hein occurrence rate of traumatic brain injury (TBI) ­ 1.4 million people in US per year ­ 50,000 deaths ­ 235

  15. Modeling of Hydrogen Storage Materials: A Reactive Force Field for NaH

    E-Print Network [OSTI]

    Goddard III, William A.

    Modeling of Hydrogen Storage Materials: A Reactive Force Field for NaH Ojwang' J.G.O.*, Rutger van is the fall in potential energy surface during heating. Keywords: hydrogen storage, reactive force field governing hydrogen desorption in NaH. During the abstraction process of surface molecular hydrogen charge

  16. Water Transport in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing,

    E-Print Network [OSTI]

    Optimization J. Vernon Cole and Ashok Gidwani CFDRC Prepared for: DOE Hydrogen Fuel Cell Kickoff MeetingWater Transport in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing, and Design fuel cell design and operation; Demonstrate improvements in water management resulting in improved

  17. 02/25/2014 27th CSP Workshop 1 First Principles Modeling of Electrolye Materials

    E-Print Network [OSTI]

    Holzwarth, Natalie

    02/25/2014 27th CSP Workshop 1 First Principles Modeling of Electrolye Materials in All Abdessadek Lachgar. #12;02/25/2014 27th CSP Workshop 2 Outline What is meant by "first principles/electrode interfaces Remaining challenges #12;02/25/2014 27th CSP Workshop 3 What is meant by "first principles

  18. A simplified model of thin layer static/flowing dynamics for granular materials with yield

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    /deposition processes when a layer of particles is flowing over a static layer or near the destabilization and arrestA simplified model of thin layer static/flowing dynamics for granular materials with yield, 75005 Paris, France, 4 ANGE team, INRIA, CETMEF, Lab. J.-L. Lions, Paris, France Abstract We introduce

  19. Extension of a Current Continuum-Level Material Model for Soil into the Low-Density Discrete-Particle Regime

    E-Print Network [OSTI]

    Grujicic, Mica

    energies of the soil as well as into surface energy of the fractured soil particles. In this caseExtension of a Current Continuum-Level Material Model for Soil into the Low-Density Discrete a soil-material model which can be used over a wide range of soil densities. To construct such a model

  20. A second gradient theoretical framework for hierarchical multiscale modeling of materials

    SciTech Connect (OSTI)

    Luscher, Darby J [Los Alamos National Laboratory; Bronkhorst, Curt A [Los Alamos National Laboratory; Mc Dowell, David L [GEORGIA TECH

    2009-01-01T23:59:59.000Z

    A theoretical framework for the hierarchical multiscale modeling of inelastic response of heterogeneous materials has been presented. Within this multiscale framework, the second gradient is used as a non local kinematic link between the response of a material point at the coarse scale and the response of a neighborhood of material points at the fine scale. Kinematic consistency between these scales results in specific requirements for constraints on the fluctuation field. The wryness tensor serves as a second-order measure of strain. The nature of the second-order strain induces anti-symmetry in the first order stress at the coarse scale. The multiscale ISV constitutive theory is couched in the coarse scale intermediate configuration, from which an important new concept in scale transitions emerges, namely scale invariance of dissipation. Finally, a strategy for developing meaningful kinematic ISVs and the proper free energy functions and evolution kinetics is presented.

  1. Modeling the interaction of high power ion or electron beams with solid target materials

    SciTech Connect (OSTI)

    Hassanein, A.M.

    1983-11-01T23:59:59.000Z

    Intense energy deposition on first wall materials and other components as a result of plasma disruptions in magnetic fusion devices are expected to cause melting and vaporization of these materials. The exact amount of vaporization losses and melt layer thickness are very important to fusion reactor design and lifetime. Experiments using ion or electron beams to simulate the disruption effects have different environments than the actual disruption conditions in fusion reactors. A model has been developed to accurately simulate the beam-target interactions so that the results from such experiments can be meaningful and useful to reactor design. This model includes a two dimensional solution of the heat conduction equation with moving boundaries. It is found that the vaporization and melting of the sample strongly depends on the characteristics of the beam spatial distribution, beam diameter, and on the power-time variation of the beam.

  2. A Free Energy Model for Piezoceramic Materials Ralph C. Smith , Stefan Seelecke y and Zoubeida Ounaies z

    E-Print Network [OSTI]

    A Free Energy Model for Piezoceramic Materials Ralph C. Smith #3; , Stefan Seelecke y and Zoubeida the development of a free energy model for quantifying the hysteresis and constitutive nonlinearities inherent to piezoceramic materials. In the #12;rst step of the development, free energy relations for a single crystal

  3. JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES Vol. 3, No. 7, 2008

    E-Print Network [OSTI]

    Wadley, Haydn

    materials, composites, microbuckling, honeycomb, carbon fiber, carbon fibre. 1315 #12;1316 BENJAMIN P. WADLEY Carbon fibre epoxy matrix composite honeycombs have been fabricated by slotting, assembling modes were elastic buckling or shear failure of the composite sheet material. Analytical models

  4. FAILURE PREDICTION AND STRESS ANALYSIS OF MICROCUTTING TOOLS

    E-Print Network [OSTI]

    Chittipolu, Sujeev

    2010-07-14T23:59:59.000Z

    -based products are limited because silicon is brittle. Products can be made from other engineering materials and need to be machined in microscale. This research deals with predicting microtool failure by studying spindle runout and tool deflection effects...

  5. An elastic-perfectly plastic flow model for finite element analysis of perforated materials

    SciTech Connect (OSTI)

    Jones, D.P.; Gordon, J.L.; Hutula, D.N.; Banas, D.; Newman, J.B.

    1999-02-01T23:59:59.000Z

    This paper describes the formulation of an elastic-perfectly plastic flow theory applicable to equivalent solid [EQS] modeling of perforated materials. An equilateral triangular array of circular penetrations is considered. The usual assumptions regarding geometry and loading conditions applicable to the development of elastic constants for EQS modeling of perforated plates are considered to apply here. An elastic-perfectly plastic [EPP] EQS model is developed for a collapse surface that includes fourth-order stress terms. The fourth order yield function has been shown to be appropriate for plates with a triangular array of circular holes. A complete flow model is formulated using the consistent tangent modulus approach based on the fourth order yield function.

  6. General Heat Transfer Characterization and Empirical Models of Material Storage Temperatures for the Los Alamos Nuclear Materials Storage Facility

    SciTech Connect (OSTI)

    J. D. Bernardin; W. S. Gregory

    1998-10-01T23:59:59.000Z

    The Los Alamos National Laboratory's Nuclear Materials Storage Facility (NMSF) is being renovated for long-term storage of canisters designed to hold heat-generating nuclear materials. A fully passive cooling scheme, relying on the transfer of heat by conduction, free convection, and radiation has been proposed as a reliable means of maintaining material at acceptable storage temperatures. The storage concept involves placing radioactive materials, with a net heat-generation rate of 10 W to 20 W, inside a set of nested steel canisters. The canisters are, in placed in holding fixtures and positioned vertically within a steel storage pipe. Several hundred drywells are arranged in a linear array within a large bay and dissipate the waste heat to the surrounding air, thus creating a buoyancy driven airflow pattern that draws cool air into the storage facility and exhausts heated air through an outlet stack. In this study, an experimental apparatus was designed to investigate the thermal characteristics of simulated nuclear materials placed inside two nested steel canisters positioned vertically on an aluminum fixture plate and placed inside a section of steel pipe. The heat-generating nuclear materials were simulated with a solid aluminum cylinder containing .an embedded electrical resistance heater. Calibrated type T thermocouples (accurate to ~ O.1 C) were used to monitor temperatures at 20 different locations within the apparatus. The purposes of this study were to observe the heat dissipation characteristics of the proposed `canister/fixture plate storage configuration, to investigate how the storage system responds to changes in various parameters, and to develop and validate empirical correlations to predict material temperatures under various operating conditions

  7. Two- and Three-Dimensional Microstructural Modeling of Asphalt Particulate Composite Materials using a Unified Viscoelastic-Viscoplastic-Viscodamage Constitutive Model

    E-Print Network [OSTI]

    You, Taesun

    2013-08-13T23:59:59.000Z

    The main objective of this study is to develop and validate a framework for microstructural modeling of asphalt composite materials using a coupled thermo-viscoelastic, thermo-viscoplastic, and thermo-viscodamage constitutive model. In addition...

  8. Meso-Scale Modeling of Spall in a Heterogeneous Two-Phase Material

    SciTech Connect (OSTI)

    Springer, H K

    2008-06-26T23:59:59.000Z

    The influence of the heterogeneous second-phase particle structure and applied loading conditions on the ductile spall response of a model two-phase material was investigated. Quantitative metallography, three-dimensional (3D) meso-scale simulations (MSS), and small-scale spall experiments provided the foundation for this study. Nodular ductile iron (NDI) was selected as the model two-phase material for this study because it contains a large and readily identifiable second- phase particle population. Second-phase particles serve as the primary void nucleation sites in NDI and are, therefore, central to its ductile spall response. A mathematical model was developed for the NDI second-phase volume fraction that accounted for the non-uniform particle size and spacing distributions within the framework of a length-scale dependent Gaussian probability distribution function (PDF). This model was based on novel multiscale sampling measurements. A methodology was also developed for the computer generation of representative particle structures based on their mathematical description, enabling 3D MSS. MSS were used to investigate the effects of second-phase particle volume fraction and particle size, loading conditions, and physical domain size of simulation on the ductile spall response of a model two-phase material. MSS results reinforce existing model predictions, where the spall strength metric (SSM) logarithmically decreases with increasing particle volume fraction. While SSM predictions are nearly independent of applied load conditions at lower loading rates, which is consistent with previous studies, loading dependencies are observed at higher loading rates. There is also a logarithmic decrease in SSM for increasing (initial) void size, as well. A model was developed to account for the effects of loading rate, particle size, matrix sound-speed, and, in the NDI-specific case, the probabilistic particle volume fraction model. Small-scale spall experiments were designed and executed for the purpose of validating closely-coupled 3D MSS. While the spall strength is nearly independent of specimen thickness, the fragment morphology varies widely. Detailed MSS demonstrate that the interactions between the tensile release waves are altered by specimen thickness and that these interactions are primarily responsible for fragment formation. MSS also provided insights on the regional amplification of damage, which enables the development of predictive void evolution models.

  9. Theory, modeling and instrumentation for materials by design: Proceedings of workshop

    SciTech Connect (OSTI)

    Allen, R.E.; Cocke, D.L.; Eberhardt, J.J.; Wilson, A. (eds.)

    1984-01-01T23:59:59.000Z

    The following topics are contained in this volume: how can materials theory benefit from supercomputers and vice-versa; the materials of xerography; relationship between ab initio and semiempirical theories of electronic structure and renormalization group and the statistical mechanics of polymer systems; ab initio calculations of materials properties; metals in intimate contact; lateral interaction in adsorption: revelations from phase transitions; quantum model of thermal desorption and laser stimulated desorption; extended fine structure in appearance potential spectroscopy as a probe of solid surfaces; structural aspects of band offsets at heterojunction interfaces; multiconfigurational Green's function approach to quantum chemistry; wavefunctions and charge densities for defects in solids: a success for semiempirical theory; empirical methods for predicting the phase diagrams of intermetallic alloys; theoretical considerations regarding impurities in silicon and the chemisorption of simple molecules on Ni; improved Kohn-Sham exchange potential; structural stability calculations for films and crystals; semiempirical molecular orbital modeling of catalytic reactions including promoter effects; theoretical studies of chemical reactions: hydrolysis of formaldehyde; electronic structure calculations for low coverage adlayers; present status of the many-body problem; atomic scattering as a probe of physical adsorption; and, discussion of theoretical techniques in quantum chemistry and solid state physics.

  10. Rheological properties vs Local Dynamics in model disordered materials at Low Temperature

    E-Print Network [OSTI]

    C. Fusco; T. Albaret; A. Tanguy

    2014-03-31T23:59:59.000Z

    We study the rheological response at low temperature of a sheared model disordered material as a function of the bond rigidity. We find that the flow curves follow a Herschel-Bulkley law, whatever is the bond rigidity, with an exponent close to 0.5. Interestingly, the apparent viscosity can be related to a single relevant time scale $t_{rel}$, suggesting a strong connection between the local dynamics and the global mechanical behaviour. We propose a model based on the competition between the nucleation and the avalanche-like propagation of spatial strain heterogeneities. This model can explain the Herschel-Bulkley exponent on the basis of the size dependence of the heterogeneities on the shear rate.

  11. Examination of the damage and failure response of tantalum and copper under varied shock loading conditions

    SciTech Connect (OSTI)

    Bronkhorst, Curt A [Los Alamos National Laboratory; Dennis - Koller, Darcie [Los Alamos National Laboratory; Cerreta, Ellen K [Los Alamos National Laboratory; Gray Ill, George T [Los Alamos National Laboratory; Bourne, Neil [AWE-ALDERMASTON

    2010-12-16T23:59:59.000Z

    A number of plate impact experiments have been conducted on high purity polycrystalline tantalum and copper samples using graded flyer plate configurations to alter the loading profile. These experiments are designed in a way so that a broad range of damage regimes are probed. The results show that the nucleation of damage primarily occurs at the grain boundaries of the materials. This affords us the opportunity to propose a porosity damage nucleation criterion which begins to account for the length scales of the microstructure (grain size distribution) and the mechanical response of the grain boundary regions (failure stress distribution). This is done in the context of a G-T-N type model for the ductile damage and failure response of both the materials examined. The role of micro-inertial effects on the porosity growth process is also considered.

  12. Modeling the Production of Beta-Delayed Gamma Rays for the Detection of Special Nuclear Materials

    SciTech Connect (OSTI)

    Hall, J M; Pruet, J A; Brown, D A; Descalle, M; Hedstrom, G W; Prussin, S G

    2005-02-14T23:59:59.000Z

    The objective of this LDRD project was to develop one or more models for the production of {beta}-delayed {gamma} rays following neutron-induced fission of a special nuclear material (SNM) and to define a standardized formatting scheme which will allow them to be incorporated into some of the modern, general-purpose Monte Carlo transport codes currently being used to simulate inspection techniques proposed for detecting fissionable material hidden in sea-going cargo containers. In this report, we will describe a Monte Carlo model for {beta}-delayed {gamma}-ray emission following the fission of SNM that can accommodate arbitrary time-dependent fission rates and photon collection histories. The model involves direct sampling of the independent fission yield distributions of the system, the branching ratios for decay of individual fission products and spectral distributions representing photon emission from each fission product and for each decay mode. While computationally intensive, it will be shown that this model can provide reasonably detailed estimates of the spectra that would be recorded by an arbitrary spectrometer and may prove quite useful in assessing the quality of evaluated data libraries and identifying gaps in the libraries. The accuracy of the model will be illustrated by comparing calculated and experimental spectra from the decay of short-lived fission products following the reactions {sup 235}U(n{sub th}, f) and {sup 239}Pu(n{sub th}, f). For general-purpose transport calculations, where a detailed consideration of the large number of individual {gamma}-ray transitions in a spectrum may not be necessary, it will be shown that a simple parameterization of the {gamma}-ray source function can be defined which provides high-quality average spectral distributions that should suffice for calculations describing photons being transported through thick attenuating media. Finally, a proposal for ENDF-compatible formats that describe each of the models and allow for their straightforward use in Monte Carlo codes will be presented.

  13. Casimir Piston of Real Materials and its Application to Multi-Layer Models

    E-Print Network [OSTI]

    L. P. Teo

    2010-02-28T23:59:59.000Z

    In this article, we derive the formula for the Casimir force acting on a piston made of real material moving inside a perfectly conducting rectangular box. It is shown that by taking suitable limits, one recovers the formula for the Casimir force acting on a perfectly conducting piston or an infinitely permeable piston. Lifshitz formula for finite temperature Casimir force acting on parallel plates made of real materials is re-derived by considering the five-layer model in the context of piston approach. It is observed that the divergences of the Casimir force will only cancel under certain conditions, for example, when the regions separated by the plates are filled with media of the same refractive index.

  14. WaterTransport in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing and Design Optimization

    SciTech Connect (OSTI)

    J. Vernon Cole; Abhra Roy; Ashok Damle; Hari Dahr; Sanjiv Kumar; Kunal Jain; Ned Djilai

    2012-10-02T23:59:59.000Z

    Water management in Proton Exchange Membrane, PEM, Fuel Cells is challenging because of the inherent conflicts between the requirements for efficient low and high power operation. Particularly at low powers, adequate water must be supplied to sufficiently humidify the membrane or protons will not move through it adequately and resistance losses will decrease the cell efficiency. At high power density operation, more water is produced at the cathode than is necessary for membrane hydration. This excess water must be removed effectively or it will accumulate in the Gas Diffusion Layers, GDLs, between the gas channels and catalysts, blocking diffusion paths for reactants to reach the catalysts and potentially flooding the electrode. As power density of the cells is increased, the challenges arising from water management are expected to become more difficult to overcome simply due to the increased rate of liquid water generation relative to fuel cell volume. Thus, effectively addressing water management based issues is a key challenge in successful application of PEMFC systems. In this project, CFDRC and our partners used a combination of experimental characterization, controlled experimental studies of important processes governing how water moves through the fuel cell materials, and detailed models and simulations to improve understanding of water management in operating hydrogen PEM fuel cells. The characterization studies provided key data that is used as inputs to all state-of-the-art models for commercially important GDL materials. Experimental studies and microscopic scale models of how water moves through the GDLs showed that the water follows preferential paths, not branching like a river, as it moves toward the surface of the material. Experimental studies and detailed models of water and airflow in fuel cells channels demonstrated that such models can be used as an effective design tool to reduce operating pressure drop in the channels and the associated costs and weight of blowers and pumps to force air and hydrogen gas through the fuel cell. Promising improvements to materials structure and surface treatments that can potentially aid in managing the distribution and removal of liquid water were developed; and improved steady-state and freeze-thaw performance was demonstrated for a fuel cell stack under the self-humidified operating conditions that are promising for stationary power generation with reduced operating costs.

  15. Radiological Modeling for Determination of Derived Concentration Levels of an Area with Uranium Residual Material - 13533

    SciTech Connect (OSTI)

    Perez-Sanchez, Danyl [CIEMAT, Avenida Complutense 40, 28040, Madrid (Spain)] [CIEMAT, Avenida Complutense 40, 28040, Madrid (Spain)

    2013-07-01T23:59:59.000Z

    As a result of a pilot project developed at the old Spanish 'Junta de Energia Nuclear' to extract uranium from ores, tailings materials were generated. Most of these residual materials were sent back to different uranium mines, but a small amount of it was mixed with conventional building materials and deposited near the old plant until the surrounding ground was flattened. The affected land is included in an area under institutional control and used as recreational area. At the time of processing, uranium isotopes were separated but other radionuclides of the uranium decay series as Th-230, Ra-226 and daughters remain in the residue. Recently, the analyses of samples taken at different ground's depths confirmed their presence. This paper presents the methodology used to calculate the derived concentration level to ensure that the reference dose level of 0.1 mSv y-1 used as radiological criteria. In this study, a radiological impact assessment was performed modeling the area as recreational scenario. The modelization study was carried out with the code RESRAD considering as exposure pathways, external irradiation, inadvertent ingestion of soil, inhalation of resuspended particles, and inhalation of radon (Rn-222). As result was concluded that, if the concentration of Ra-226 in the first 15 cm of soil is lower than, 0.34 Bq g{sup -1}, the dose would not exceed the reference dose. Applying this value as a derived concentration level and comparing with the results of measurements on the ground, some areas with a concentration of activity slightly higher than latter were found. In these zones the remediation proposal has been to cover with a layer of 15 cm of clean material. This action represents a reduction of 85% of the dose and ensures compliance with the reference dose. (authors)

  16. alpha-mode containment failure: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Summary: of stainless steel container materials is a potential problem for long-term radioactive waste storage-to-failure of relevant stainless steels in the annealed...

  17. Systems Modeling, Simulation and Material Operating Requirements for Chemical Hydride Based Hydrogen Storage

    SciTech Connect (OSTI)

    Devarakonda, Maruthi N.; Brooks, Kriston P.; Ronnebro, Ewa; Rassat, Scot D.

    2012-02-01T23:59:59.000Z

    Research on ammonia borane (AB, NH3BH3) has shown it to be a promising material for chemical hydride based hydrogen storage. AB was selected by DOE's Hydrogen Storage Engineering Center of Excellence (HSECoE) as the initial chemical hydride of study because of its high hydrogen storage capacity (up to 19.6% by weight for the release of {approx}2.5 molar equivalents of hydrogen gas) and its stability under typical ambient conditions. A new systems concept based on augers, ballast tank, hydrogen heat exchanger and H2 burner was designed and implemented in simulation. In this design, the chemical hydride material was assumed to produce H2 on the augers itself, thus minimizing the size of ballast tank and reactor. One dimensional models based on conservation of mass, species and energy were used to predict important state variables such as reactant and product concentrations, temperatures of various components, flow rates, along with pressure, in various components of the storage system. Various subsystem components in the models were coded as C language S-functions and implemented in Matlab/Simulink environment. The control variable AB (or alane) flow rate was determined through a simple expression based on the ballast tank pressure, H2 demand from the fuel cell and hydrogen production from AB (or alane) in the reactor. System simulation results for solid AB, liquid AB and alane for both steady state and transient drive cycle cases indicate the usefulness of the model for further analysis and prototype development.

  18. Electrical overstress failure in silicon solar cells

    SciTech Connect (OSTI)

    Pease, R.L.; Barnum, J.R.; van Lint, V.A.J.; Vulliet, W.V.; Wrobel, T.F.

    1982-11-01T23:59:59.000Z

    A solar-cell electrical-overstress-failure model and the results of experimental measurements of threshold pulsed failure currents on four types of silicon solar cells are presented. The transient EMP field surrounding a lightning stroke has been identified as a potential threat to a photovoltaic array, yet failure analysis of solar cells in a pulsed environment had not previously been reported. Failure in the low-resistivity concentrator cells at pulse widths between 1 ..mu..s and 1 ms occurred initially in the junction. Finger damage in the form of silver melting occurs at currents only slightly greater than that required for junction damage. The result of reverse-bias transient-overstress tests on high-resistivity (10 ..cap omega..cm) cells demonstrated that the predominant failure mode was due to edge currents. These flat-plate cells failed at currents of only 4 to 20 A, which is one or two orders of magnitude below the model predictions. It thus appears that high-resistivity flat-plate cells are quite vulnerable to electrical overstress which could be produced by a variety of mechanisms.

  19. Demonstration of a computer model for residual radioactive material guidelines, RESRAD

    SciTech Connect (OSTI)

    Yu, C.; Yuan, Y.C.; Zielen, A.J.; Wallo, A. III (Argonne National Lab., IL (USA); USDOE, Washington, DC (USA))

    1989-01-01T23:59:59.000Z

    A computer model was developed to calculate residual radioactive material guidelines for the US Department of Energy (DOE). This model, called RESRAD, can be run on IBM or IBM-compatible microcomputer. Seven potential exposure pathways from contaminated soil are analyzed, including external radiation exposure and internal radiation exposure from inhalation and food digestion. The RESRAD code has been applied to several DOE sites to derive soil cleanup guidelines. The experience gained indicates that a comprehensive set of site-specific hydrogeologic and geochemical input parameters must be used for a realistic pathway analysis. The RESRAD code is a useful tool; it is easy to run and very user-friendly. 6 refs., 12 figs.

  20. Development of a sub-scale dynamics model for pressure relaxation of multi-material cells in Lagrangian hydrodynamics

    SciTech Connect (OSTI)

    Harrison, Alan K [Los Alamos National Laboratory; Shashkov, Mikhail J [Los Alamos National Laboratory; Fung, Jimmy [Los Alamos National Laboratory; Canfield, Thomas R [Los Alamos National Laboratory; Kamm, James R [SNLA

    2010-10-14T23:59:59.000Z

    We have extended the Sub-Scale Dynamics (SSD) closure model for multi-fluid computational cells. Volume exchange between two materials is based on the interface area and a notional interface translation velocity, which is derived from a linearized Riemann solution. We have extended the model to cells with any number of materials, computing pressure-difference-driven volume and energy exchange as the algebraic sum of pairwise interactions. In multiple dimensions, we rely on interface reconstruction to provide interface areas and orientations, and centroids of material polygons. In order to prevent unphysically large or unmanageably small material volumes, we have used a flux-corrected transport (FCT) approach to limit the pressure-driven part of the volume exchange. We describe the implementation of this model in two dimensions in the FLAG hydrodynamics code. We also report on Lagrangian test calculations, comparing them with others made using a mixed-zone closure model due to Tipton, and with corresponding calculations made with only single-material cells. We find that in some cases, the SSD model more accurately predicts the state of material in mixed cells. By comparing the algebraic forms of both models, we identify similar dependencies on state and dynamical variables, and propose explanations for the apparent higher fidelity of the SSD model.

  1. Eliciting a human understandable model of ice adhesion strength for rotor blade leading edge materials from uncertain experimental data

    E-Print Network [OSTI]

    Granada, Universidad de

    Eliciting a human understandable model of ice adhesion strength for rotor blade leading edge: Genetic Fuzzy Systems Fuzzy rule-based classifiers Vague data Isotropic materials Ice-phobic materials Shear adhesion strength a b s t r a c t The published ice adhesion performance data of novel ``ice

  2. “Playboy Bunny” Sign of Congestive Heart Failure

    E-Print Network [OSTI]

    Hokama, Akira; Arakaki, Shingo; Shibata, Daisuke; Maeshiro, Tatsuji; Kinjo, Fukunori; Fujita, Jiro

    2011-01-01T23:59:59.000Z

    Bunny’’ Sign of Congestive Heart Failure Akira Hokama, MD*to evaluate congestive heart failure. We highlight ‘‘Playboycaused by congestive heart failure. [West J Emerg Med. 2011;

  3. Combination stem cell therapy for heart failure

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    to further analyze his heart failure. Com- plete bloodA: Inflammatory markers in stable heart failure and theirof improvement and readmission in heart failure. Eur J Heart

  4. Modeling and Design of Material Separation Systems with Applications to Recycling

    E-Print Network [OSTI]

    Wolf, Malima Isabelle, 1981-

    2011-01-01T23:59:59.000Z

    Material separation technology is critical to the success of the material recycling industry. End-of-life products, post-consumer waste, industrial excess, or otherwise collected materials for reuse are typically mixed ...

  5. Lattice Boltzmann modeling of the effective thermal conductivity for fibrous materials

    E-Print Network [OSTI]

    Wang, Moran; He, Jihuan; Yu, Jianyong; Pan, Ning

    2007-01-01T23:59:59.000Z

    composites. Journal of Materials Science, 1997. 32(8): p.problem. Computational Materials Science, 2004. 31(1-2): p.properties. Journal of Materials Research, 2001. 16(1): p.

  6. Steam generator tube failures

    SciTech Connect (OSTI)

    MacDonald, P.E.; Shah, V.N.; Ward, L.W.; Ellison, P.G.

    1996-04-01T23:59:59.000Z

    A review and summary of the available information on steam generator tubing failures and the impact of these failures on plant safety is presented. The following topics are covered: pressurized water reactor (PWR), Canadian deuterium uranium (CANDU) reactor, and Russian water moderated, water cooled energy reactor (VVER) steam generator degradation, PWR steam generator tube ruptures, the thermal-hydraulic response of a PWR plant with a faulted steam generator, the risk significance of steam generator tube rupture accidents, tubing inspection requirements and fitness-for-service criteria in various countries, and defect detection reliability and sizing accuracy. A significant number of steam generator tubes are defective and are removed from service or repaired each year. This wide spread damage has been caused by many diverse degradation mechanisms, some of which are difficult to detect and predict. In addition, spontaneous tube ruptures have occurred at the rate of about one every 2 years over the last 20 years, and incipient tube ruptures (tube failures usually identified with leak detection monitors just before rupture) have been occurring at the rate of about one per year. These ruptures have caused complex plant transients which have not always been easy for the reactor operators to control. Our analysis shows that if more than 15 tubes rupture during a main steam line break, the system response could lead to core melting. Although spontaneous and induced steam generator tube ruptures are small contributors to the total core damage frequency calculated in probabilistic risk assessments, they are risk significant because the radionuclides are likely to bypass the reactor containment building. The frequency of steam generator tube ruptures can be significantly reduced through appropriate and timely inspections and repairs or removal from service.

  7. 3.22 Mechanical Properties of Materials, Spring 2003

    E-Print Network [OSTI]

    Gibson, Lorna J.

    Phenomenology of mechanical behavior of materials at the macroscopic level. Relationship of mechanical behavior to material structure and mechanisms of deformation and failure. Topics include: elasticity, viscoelasticity, ...

  8. Efficient Failure Detection for Mobile Robots Using Mixed-Abstraction Particle Filters

    E-Print Network [OSTI]

    Stachniss, Cyrill

    Efficient Failure Detection for Mobile Robots Using Mixed-Abstraction Particle Filters Christian the problem of online failure detection and isolation for mobile robots. The goal is to enable a mobile robot failures of mobile robots. It uses a hierarchy of process models to actively validate the model assumptions

  9. Ris-R-1261(EN) Fatigue Degradation and Failure of

    E-Print Network [OSTI]

    . Such applications are for instance rotor blades in wind turbines, helicopter rotor blades, flywheels for energyRisø-R-1261(EN) Fatigue Degradation and Failure of Rotating Composite Structures ­ Materials Characterisation and Underlying Mechanisms E. Kristofer Gamstedt and Svend Ib Andersen Materials Research

  10. E-Print Network 3.0 - assisted failures initiating Sample Search...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    4 5 > >> 1 Failure Modelling in Software Architecture Design for Safety Weihang Wu Tim Kelly Summary: modelling assist the architectural design process? How can CSP be applied to...

  11. Modeling of the Effective Elastic and Thermal Properties of Glass-Ceramic Solid Oxide Fuel Cell Seal Materials

    SciTech Connect (OSTI)

    Milhans, Jacqueline; Ahzi, Said; Garmestani, Hamid; Khaleel, Mohammad A.; Sun, Xin; Koeppel, Brian J.

    2009-05-01T23:59:59.000Z

    In this study, the effective elastic properties and coefficients of thermal expansion (CTE) of a glass-ceramic were predicted using homogenization techniques. Using G18, a glass-ceramic solid oxide fuel cell (SOFC) sealant as an initial reference material, the effectiveness of different homogenization models was investigated for a two-phase glass-ceramic. The elastic properties and CTEs of the G18 amorphous phase are currently unknown. Thus, estimated values were used as an input to the models. The predictive model offers accurate macroscopic values on both the elastic modulus and the CTE of glass-ceramic materials, providing the estimated amorphous values are reasonable. This model can be used in designing glass-ceramic SOFC seal materials for its specific operation conditions.

  12. Application of the method of effective potentials to a model for twinning in elastic materials

    SciTech Connect (OSTI)

    Marianer, S.; Floria, L.M.

    1988-12-01T23:59:59.000Z

    We extend the method of effective potentials to systems with next-nearest-neighbor interactions, and apply it to a one-dimensional discrete model for twins in elastic materials. The energy of the system is given by H = +(..gamma../2) (u/sub n//sub +1/-2u/sub n/+u/sub n-1/)/sup 2/ -cosu/sub n/, where the first two terms model the elastic strain-dependent energy which we take to be in the form of a double well in the strains and the third term gives its dependence on the discretized strain gradients. The periodic potential in the last term is introduced to allow for additional interactions with a background such as a parent phase, grain boundaries, or another array of twins. We obtain the phase diagram and show that it consists of various modulated commensurate as well as incommensurate ground-state configurations. We find continuous phonon-driven transitions between the homogeneous and any modulated phase, an incomplete devil's staircase in a narrow region close to the homogeneous phase and first-order soliton-driven transitions between commensurate phases. The first-order transition lines end at triple points where three commensurate phases coexist. In contrast to other nonconvex models we do not find here any superdegenerate points. We give general arguments which exclude the existence of such points in the present model. Preliminary results obtained by driving the system are discussed. These consist of various metastable configurations exhibiting strong hysteretic variation with the driving force.

  13. Component failure data handbook

    SciTech Connect (OSTI)

    Gentillon, C.D.

    1991-04-01T23:59:59.000Z

    This report presents generic component failure rates that are used in reliability and risk studies of commercial nuclear power plants. The rates are computed using plant-specific data from published probabilistic risk assessments supplemented by selected other sources. Each data source is described. For rates with four or more separate estimates among the sources, plots show the data that are combined. The method for combining data from different sources is presented. The resulting aggregated rates are listed with upper bounds that reflect the variability observed in each rate across the nuclear power plant industry. Thus, the rates are generic. Both per hour and per demand rates are included. They may be used for screening in risk assessments or for forming distributions to be updated with plant-specific data.

  14. Insights in fundamental scratch behavior of polymeric materials

    E-Print Network [OSTI]

    Moghbelli, Ehsan

    2009-06-02T23:59:59.000Z

    of polymeric materials under scratch deformations are dependent on the type and physical nature of the material, whereas brittle and ductile materials show various behaviors under the specified conditions. Based on the failure mechanism which the material...

  15. Lightweighting Automotive Materials for Increased Fuel Efficiency and Delivering Advanced Modeling and Simulation Capabilities to U.S. Manufacturers

    SciTech Connect (OSTI)

    Hale, Steve

    2013-09-11T23:59:59.000Z

    Abstract The National Center for Manufacturing Sciences (NCMS) worked with the U.S. Department of Energy (DOE), National Energy Technology Laboratory (NETL), to bring together research and development (R&D) collaborations to develop and accelerate the knowledgebase and infrastructure for lightweighting materials and manufacturing processes for their use in structural and applications in the automotive sector. The purpose/importance of this DOE program: • 2016 CAFÉ standards. • Automotive industry technology that shall adopt the insertion of lightweighting material concepts towards manufacturing of production vehicles. • Development and manufacture of advanced research tools for modeling and simulation (M&S) applications to reduce manufacturing and material costs. • U.S. competitiveness that will help drive the development and manufacture of the next generation of materials. NCMS established a focused portfolio of applied R&D projects utilizing lightweighting materials for manufacture into automotive structures and components. Areas that were targeted in this program: • Functionality of new lightweighting materials to meet present safety requirements. • Manufacturability using new lightweighting materials. • Cost reduction for the development and use of new lightweighting materials. The automotive industry’s future continuously evolves through innovation, and lightweight materials are key in achieving a new era of lighter, more efficient vehicles. Lightweight materials are among the technical advances needed to achieve fuel/energy efficiency and reduce carbon dioxide (CO2) emissions: • Establish design criteria methodology to identify the best materials for lightweighting. • Employ state-of-the-art design tools for optimum material development for their specific applications. • Match new manufacturing technology to production volume. • Address new process variability with new production-ready processes.

  16. Modeling and Simulation in Material Sciences and Engineering, 1:(3),pp. 225263. COMPUTATIONAL MODELLING OF SINGLE CRYSTALS

    E-Print Network [OSTI]

    Ortiz, Michael

    in propeller and turbine blades, or as basic building blocks of numerous material systems, such as polycrys

  17. Computationally efficient algorithms for modelling thermal degradation and spiking phenomena in polymeric materials

    E-Print Network [OSTI]

    Melnik, Roderick

    resistance are the key factors that determine a wide spread success of these materials (Flipsen et al., 1996. These phenomena may contribute substantially to the overall thermal degrada- tion of the material at the stage of material applications. To predict the onset of thermal spiking is not an easy task, and in order

  18. Multi-Length Scale-Enriched Continuum-Level Material Model for Kevlar

    E-Print Network [OSTI]

    Grujicic, Mica

    engineering analyses of ballistic/blast impact protective structures made of this type of material do materials and struc- tures. These materials/structures are commonly used in various protective systems whose projectiles (e.g., bullets, mine, IED or turbine fragments, etc.). Development of the aforementioned

  19. Dielectric spectroscopy at the nanoscale by atomic force microscopy: A simple model linking materials properties and experimental response

    SciTech Connect (OSTI)

    Miccio, Luis A., E-mail: luisalejandro-miccio@ehu.es; Colmenero, Juan [Centro de Física de Materiales (CSIC-UPV/EHU), P. M. de Lardizabal 5, 20018 San Sebastián (Spain); Donostia International Physics Center, P. M. de Lardizabal 4, 20018 San Sebastián (Spain); Departamento de Física de Materiales (UPV/EHU), 20080 San Sebastián (Spain); Kummali, Mohammed M.; Alegría, Ángel [Centro de Física de Materiales (CSIC-UPV/EHU), P. M. de Lardizabal 5, 20018 San Sebastián (Spain); Departamento de Física de Materiales (UPV/EHU), 20080 San Sebastián (Spain); Schwartz, Gustavo A. [Centro de Física de Materiales (CSIC-UPV/EHU), P. M. de Lardizabal 5, 20018 San Sebastián (Spain); Donostia International Physics Center, P. M. de Lardizabal 4, 20018 San Sebastián (Spain)

    2014-05-14T23:59:59.000Z

    The use of an atomic force microscope for studying molecular dynamics through dielectric spectroscopy with spatial resolution in the nanometer scale is a recently developed approach. However, difficulties in the quantitative connection of the obtained data and the material dielectric properties, namely, frequency dependent dielectric permittivity, have limited its application. In this work, we develop a simple electrical model based on physically meaningful parameters to connect the atomic force microscopy (AFM) based dielectric spectroscopy experimental results with the material dielectric properties. We have tested the accuracy of the model and analyzed the relevance of the forces arising from the electrical interaction with the AFM probe cantilever. In this way, by using this model, it is now possible to obtain quantitative information of the local dielectric material properties in a broad frequency range. Furthermore, it is also possible to determine the experimental setup providing the best sensitivity in the detected signal.

  20. Modeling Thermodynamics and Dynamics of MixtureModeling Thermodynamics and Dynamics of Mixture Adsorption in Porous MaterialsAdsorption in Porous Materials

    E-Print Network [OSTI]

    Mountziaris, T. J.

    models to describe adsorption dynamics · Apply to case of Enhanced Coalbed Methane Extraction ­ Trillions of cubic meters of methane and carbon dioxide can be extracted and stored in unusable coal seams Models temperature, adsorption increases with pressure. Carbon Dioxide interacts more strongly with coal than methane

  1. Failure Atlas for Rolling Bearings in Wind Turbines

    SciTech Connect (OSTI)

    Tallian, T. E.

    2006-01-01T23:59:59.000Z

    This Atlas is structured as a supplement to the book: T.E. Tallian: Failure Atlas for Hertz Contact Machine Elements, 2nd edition, ASME Press New York, (1999). The content of the atlas comprises plate pages from the book that contain bearing failure images, application data, and descriptions of failure mode, image, and suspected failure causes. Rolling bearings are a critical component of the mainshaft system, gearbox and generator in the rapidly developing technology of power generating wind turbines. The demands for long service life are stringent; the design load, speed and temperature regimes are demanding and the environmental conditions including weather, contamination, impediments to monitoring and maintenance are often unfavorable. As a result, experience has shown that the rolling bearings are prone to a variety of failure modes that may prevent achievement of design lives. Morphological failure diagnosis is extensively used in the failure analysis and improvement of bearing operation. Accumulated experience shows that the failure appearance and mode of failure causation in wind turbine bearings has many distinguishing features. The present Atlas is a first effort to collect an interpreted database of specifically wind turbine related rolling bearing failures and make it widely available. This Atlas is structured as a supplement to the book: T. E. Tallian: Failure Atlas for Hertz Contact Machine Elements, 2d edition, ASME Press New York, (1999). The main body of that book is a comprehensive collection of self-contained pages called Plates, containing failure images, bearing and application data, and three descriptions: failure mode, image and suspected failure causes. The Plates are sorted by main failure mode into chapters. Each chapter is preceded by a general technical discussion of the failure mode, its appearance and causes. The Plates part is supplemented by an introductory part, describing the appearance classification and failure classification systems used, and by several indexes. The present Atlas is intended as a supplement to the book. It has the same structure but contains only Plate pages, arranged in chapters, each with a chapter heading page giving a short definition of the failure mode illustrated. Each Plate page is self contained, with images, bearing and application data, and descriptions of the failure mode, the images and the suspected causes. Images are provided in two resolutions: The text page includes 6 by 9 cm images. In addition, high resolution image files are attached, to be retrieved by clicking on their 'push pin' icon. While the material in the present Atlas is self-contained, it is nonetheless a supplement to the book and the complete interpretation of the terse image descriptions and of the system underlying the failure code presupposes familiarity with the book. Since this Atlas is a supplement to the book, its chapter numbering follows that of the book. Not all failure modes covered in the book have been found among the observed wind turbines. For that reason, and because of the omission of introductory matter, the chapter numbers in this Atlas are not a continuous sequence.

  2. Failure of man-made cavities in salt and surface subsidence due to sulfur mining

    SciTech Connect (OSTI)

    Coates, G.K.; Lee, C.A.; McClain, W.C.; Senseny, P.E.

    1981-01-01T23:59:59.000Z

    An engineering data base relevant to subsidence due to sulfur mining and to structural failure of cavities in salt is established, evaluated and documented. Nineteen failure events are discussed. Based on these documented failure events, capabilities of and inputs to a mathematical model of cavity failure are determined. Two failure events are adequately documented for use in model verification studies. A conclusion of this study that is pertinent to the Strategic Petroleum Reserve is that cavity failures in dome salt are fairly rare, but that as the number of large cavities (especially those having large roof spans) increases, failures will probably be more common unless stability and failure mechanisms of cavities are better understood.

  3. The Smart Engineering Apprentice (SEA) Project is an advanced artificial intelligence model that aims to predict the future failure of rod pump units. Innovative and modern, this

    E-Print Network [OSTI]

    Shahabi, Cyrus

    The Smart Engineering Apprentice (SEA) Project is an advanced artificial intelligence model system is the apprentice of field experts, and `learns' from experts through their past experiences

  4. The Smart Engineering Apprentice (SEA) Project is an advanced artificial intelligence model that aims to predict the future failure of rod pump units. Innovative and modern, this novel

    E-Print Network [OSTI]

    Wang, Hai

    The Smart Engineering Apprentice (SEA) Project is an advanced artificial intelligence model system is the apprentice of field experts, and ,,learns from experts through their past experiences

  5. INTERFACE CRACK PROPAGATION IN POROUS AND TIME-DEPENDENT MATERIALS ANALYZED WITH

    E-Print Network [OSTI]

    Boyer, Edmond

    INTERFACE CRACK PROPAGATION IN POROUS AND TIME-DEPENDENT MATERIALS ANALYZED WITH DISCRETE MODELS and the FPZ. From the point of view of design of structures, e.g. reinforced concrete structures, this size size, size effects, creep, ageing, fracture, viscoelastic- ity, time effect, concrete failure, discrete

  6. FRACTURE FAILURE CRITERIA OF SOFC PEN STRUCTURE

    SciTech Connect (OSTI)

    Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.; Qu, Jianmin

    2007-04-30T23:59:59.000Z

    Thermal stresses and warpage of the PEN are unavoidable due to the temperature changes from the stress-free sintering temperature to room temperature and mismatch of the coefficients of thermal expansion (CTE) of various layers in the PEN structures of solid oxide fuel cells (SOFC) during the PEN manufacturing process. In the meantime, additional mechanical stresses will also be created by mechanical flattening during the stack assembly process. The porous nature of anode and cathode in the PEN structures determines presence of the initial flaws and crack on the interfaces of anode/electrolyte/cathode and in the interior of the materials. The sintering/assembling induced stresses may cause the fracture failure of PEN structure. Therefore, fracture failure criteria for SOFC PEN structures is developed in order to ensure the structural integrity of the cell and stack of SOFC. In this paper, the fracture criteria based on the relationship between the critical energy release rate and critical curvature and maximum displacement of the warped cells caused by the temperature changes as well as mechanical flattening process is established so that possible failure of SOFC PEN structures may be predicted deterministically by the measurement of the curvature and displacement of the warped cells.

  7. Verification and Validation of EnergyPlus Conduction Finite Difference and Phase Change Material Models for Opaque Wall Assemblies

    SciTech Connect (OSTI)

    Tabares-Velasco, P. C.; Christensen, C.; Bianchi, M.; Booten, C.

    2012-07-01T23:59:59.000Z

    Phase change materials (PCMs) represent a potential technology to reduce peak loads and HVAC energy consumption in buildings. There are few building energy simulation programs that have the capability to simulate PCM but their accuracy has not been completely tested. This report summarizes NREL efforts to develop diagnostic tests cases to obtain accurate energy simulations when PCMs are modeled in residential buildings.

  8. Multidiscipline Modeling in Materials and Structures Emerald Article: A study of the blast-induced brain white-matter damage

    E-Print Network [OSTI]

    Grujicic, Mica

    Multidiscipline Modeling in Materials and Structures Emerald Article: A study of the blast, (2012),"A study of the blast-induced brain white-matter damage and the associated diffuse axonal injury Abstract Purpose ­ Blast-induced traumatic brain injury (TBI) is a signature injury of the current military

  9. Accepted to Diamond and Related Materials A kinetic model of diamond nucleation and silicon carbide interlayer formation during

    E-Print Network [OSTI]

    Dandy, David

    Accepted to Diamond and Related Materials A kinetic model of diamond nucleation and silicon carbide Engineering, Colorado State University, Fort Collins, CO, USA Abstract The presence of thin silicon carbide diffusion of carbon atoms into the silicon carbide layer, and the morphology and orientation of the diamond

  10. Submission of manuscript to Energy and Buildings A thermal model for Phase Change Materials in a building roof for a

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Submission of manuscript to Energy and Buildings A thermal model for Phase Change Materials: Stéphane GUICHARD Physics and Mathematical Engineering Laboratory for Energy and Environment (PIMENT in "Energy and Buildings 70 (2014) http://www.sciencedirect.com/science/article/pii/ S0378778813007962" DOI

  11. Multiscale modeling of fluid transport in heterogeneous materials using discrete Boltzmann methods

    E-Print Network [OSTI]

    Bentz, Dale P.

    transport in porous materials like ceramics, concrete, soils, and rocks plays an impor- tant role in many geometries like porous materials. Here, we review some of our previous work and discuss some recent environmental and technological processes [11.For example, the service life and durability of concrete can

  12. Computational modeling and design of actively-cooled microvascular materials Soheil Soghrati a,b

    E-Print Network [OSTI]

    Sottos, Nancy R.

    to the optimization study, the IGFEM solver is validated through comparison with infrared measurements of the thermal of such systems to a broad field including autonomic materials [6], biotechnology [7,8], chemical reactors [9 in two specific ways: (i) by direct extraction of heat from the thermally loaded material, and (ii

  13. Micromechanics-based elastic model for functionally graded materials with particle interactions

    E-Print Network [OSTI]

    Paulino, Glaucio H.

    , and the simultaneous ability of the same material system to provide the re- quired thermal or impact resistance, a continuous trade-off of metallic toughness and high thermal conductivity is made with ceramic hardness and low thermal conductivity. In heat and impact protection applications, the material multifunctionality

  14. Simulations of Failure via Three-Dimensional Cracking in Fuel Cladding for Advanced Nuclear Fuels

    SciTech Connect (OSTI)

    Lu, Hongbing; Bukkapatnam, Satish; Harimkar, Sandip; Singh, Raman; Bardenhagen, Scott

    2014-01-09T23:59:59.000Z

    Enhancing performance of fuel cladding and duct alloys is a key means of increasing fuel burnup. This project will address the failure of fuel cladding via three-dimensional cracking models. Researchers will develop a simulation code for the failure of the fuel cladding and validate the code through experiments. The objective is to develop an algorithm to determine the failure of fuel cladding in the form of three-dimensional cracking due to prolonged exposure under varying conditions of pressure, temperature, chemical environment, and irradiation. This project encompasses the following tasks: 1. Simulate 3D crack initiation and growth under instantaneous and/or fatigue loads using a new variant of the material point method (MPM); 2. Simulate debonding of the materials in the crack path using cohesive elements, considering normal and shear traction separation laws; 3. Determine the crack propagation path, considering damage of the materials incorporated in the cohesive elements to allow the energy release rate to be minimized; 4. Simulate the three-dimensional fatigue crack growth as a function of loading histories; 5. Verify the simulation code by comparing results to theoretical and numerical studies available in the literature; 6. Conduct experiments to observe the crack path and surface profile in unused fuel cladding and validate against simulation results; and 7. Expand the adaptive mesh refinement infrastructure parallel processing environment to allow adaptive mesh refinement at the 3D crack fronts and adaptive mesh merging in the wake of cracks. Fuel cladding is made of materials such as stainless steels and ferritic steels with added alloying elements, which increase stability and durability under irradiation. As fuel cladding is subjected to water, chemicals, fission gas, pressure, high temperatures, and irradiation while in service, understanding performance is essential. In the fast fuel used in advanced burner reactors, simulations of the nuclear fuels are critical to understand the burnup, and thus the fuel efficiency.

  15. Evaluation and Modeling of Edge-Seal Materials for Photovoltaic Applications

    SciTech Connect (OSTI)

    Kempe, M. D.; Dameron, A. A.; Moricone, T. J.; Reese, M. O.

    2011-02-01T23:59:59.000Z

    Because of the sensitivity of some photovoltaic devices to moisture-induced corrosion, they are packaged using impermeable front- and back-sheets along with an edge seal to prevent moisture ingress. Evaluation of edge seal materials can be difficult because of the low permeation rates involved and/or non-Fickian behavior. Here, using a Ca film deposited on a glass substrate, we demonstrate the evaluation of edge seal materials in a manner that effectively duplicates their use in a photovoltaic application and compare the results with standard methods for measuring water vapor transport. We demonstrate how moisture permeation data from polymer films can be used to estimate moisture ingress rates and compare the results of these two methods. Encapsulant materials were also evaluated for comparison and to highlight the need for edge seals. Of the materials studied, desiccant filled polyisobutylene materials demonstrate by far the best potential to keep moisture out for a 20 to 30 year lifetime.

  16. Autonomous thruster failure recovery for underactuated spacecraft

    E-Print Network [OSTI]

    Pong, Christopher Masaru

    2010-01-01T23:59:59.000Z

    Thruster failures historically account for a large percentage of failures that have occurred on orbit. Therefore, autonomous thruster failure detection, isolation, and recovery (FDIR) is an essential component to any robust ...

  17. Experience with CPV Module Failures at NREL (Presentation)

    SciTech Connect (OSTI)

    Muller, M.

    2012-03-01T23:59:59.000Z

    The failures and performance issues associated with three years of on-sun testing of CPV modules are discussed. Pictures of various failure mechanisms and performance issues are presented. A wide array of CPV module failures and performance issues have been experienced at NREL. Many of the modules are prototypes and have not been through qualification testing. It is assumed that the qualification test would have captured many of the problems. Internal lens soiling due to condensation is not currently captured by the qualification test. Lens temperature dependence can be built into modeling if CPV is to operate in cold locations.

  18. Modeling VOC sorption of building materials and its impact on indoor air quality

    E-Print Network [OSTI]

    Zhang, Jinsong, 1975-

    2001-01-01T23:59:59.000Z

    Sorption of volatile organic compounds (VOCs) by building materials can have significant effect on the indoor VOC concentration levels and indoor air quality in buildings. The objective of this study was to investigate ...

  19. Estimation of Distributed Parameters in Permittivity Models of Composite Dielectric Materials Using

    E-Print Network [OSTI]

    Metric Framework, inorganic glass. 1 #12;1 Introduction Complex materials such as ceramic matrix spectroscopy has been shown to have sensitivity to heat treated ceramic thermal barrier coatings, which

  20. Physical understanding and modeling of chemical mechanical planarization in dielectric materials

    E-Print Network [OSTI]

    Xie, Xiaolin, Ph. D. Massachusetts Institute of Technology

    2007-01-01T23:59:59.000Z

    Chemical mechanical planarization (CMP) has become the enabling planarization technique of choice for current and emerging silicon integrated circuit (IC) fabrication processes. This work studies CMP in dielectric materials ...

  1. INSTITUTE OF PHYSICS PUBLISHING MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING Modelling Simul. Mater. Sci. Eng. 10 (2002) 119 PII: S0965-0393(02)55385-7

    E-Print Network [OSTI]

    Ghoniem, Nasr M.

    INSTITUTE OF PHYSICS PUBLISHING MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING in the two- dimensional case, it has been realized that the fundamental physical nature of dislocation 1 of the DD methodology to the more physical, yet, considerably more complex conditions of three

  2. Statistical analysis of cascading failures in power grids

    SciTech Connect (OSTI)

    Chertkov, Michael [Los Alamos National Laboratory; Pfitzner, Rene [Los Alamos National Laboratory; Turitsyn, Konstantin [Los Alamos National Laboratory

    2010-12-01T23:59:59.000Z

    We introduce a new microscopic model of cascading failures in transmission power grids. This model accounts for automatic response of the grid to load fluctuations that take place on the scale of minutes, when optimum power flow adjustments and load shedding controls are unavailable. We describe extreme events, caused by load fluctuations, which cause cascading failures of loads, generators and lines. Our model is quasi-static in the causal, discrete time and sequential resolution of individual failures. The model, in its simplest realization based on the Directed Current description of the power flow problem, is tested on three standard IEEE systems consisting of 30, 39 and 118 buses. Our statistical analysis suggests a straightforward classification of cascading and islanding phases in terms of the ratios between average number of removed loads, generators and links. The analysis also demonstrates sensitivity to variations in line capacities. Future research challenges in modeling and control of cascading outages over real-world power networks are discussed.

  3. Modeling most likely pathways for smuggling radioactive and special nuclear materials on a worldwide multimodal transportation network

    SciTech Connect (OSTI)

    Saeger, Kevin J [Los Alamos National Laboratory; Cuellar, Leticia [Los Alamos National Laboratory

    2010-01-01T23:59:59.000Z

    Nuclear weapons proliferation is an existing and growing worldwide problem. To help with devising strategies and supporting decisions to interdict the transport of nuclear material, we developed the Pathway Analysis, Threat Response and Interdiction Options Tool (PATRIOT) that provides an analytical approach for evaluating the probability that an adversary smuggling radioactive or special nuclear material will be detected during transit. We incorporate a global, multi-modal transportation network, explicit representation of designed and serendipitous detection opportunities, and multiple threat devices, material types, and shielding levels. This paper presents the general structure of PATRIOT, and focuses on the theoretical framework used to model the reliabilities of all network components that are used to predict the most likely pathways to the target.

  4. Modeling most likely pathways for smuggling radioactive and special nuclear materials on a worldwide multi-modal transportation network

    SciTech Connect (OSTI)

    Saeger, Kevin J [Los Alamos National Laboratory; Cuellar, Leticia [Los Alamos National Laboratory

    2010-10-28T23:59:59.000Z

    Nuclear weapons proliferation is an existing and growing worldwide problem. To help with devising strategies and supporting decisions to interdict the transport of nuclear material, we developed the Pathway Analysis, Threat Response and Interdiction Options Tool (PATRIOT) that provides an analytical approach for evaluating the probability that an adversary smuggling radioactive or special nuclear material will be detected during transit. We incorporate a global, multi-modal transportation network, explicit representation of designed and serendipitous detection opportunities, and multiple threat devices, material types, and shielding levels. This paper presents the general structure of PATRIOT, all focuses on the theoretical framework used to model the reliabilities of all network components that are used to predict the most likely pathways to the target.

  5. PACER -- A fast running computer code for the calculation of short-term containment/confinement loads following coolant boundary failure. Volume 1: Code models and correlations

    SciTech Connect (OSTI)

    Sienicki, J.J.

    1997-06-01T23:59:59.000Z

    A fast running and simple computer code has been developed to calculate pressure loadings inside light water reactor containments/confinements under loss-of-coolant accident conditions. PACER was originally developed to calculate containment/confinement pressure and temperature time histories for loss-of-coolant accidents in Soviet-designed VVER reactors and is relevant to the activities of the US International Nuclear Safety Center. The code employs a multicompartment representation of the containment volume and is focused upon application to early time containment phenomena during and immediately following blowdown. Flashing from coolant release, condensation heat transfer, intercompartment transport, and engineered safety features are described using best estimate models and correlations often based upon experiment analyses. Two notable capabilities of PACER that differ from most other containment loads codes are the modeling of the rates of steam and water formation accompanying coolant release as well as the correlations for steam condensation upon structure.

  6. battery materials | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    battery materials battery materials Leads No leads are available at this time. Modeling Interfacial Glass-Water Reactions: Recent Advances and Current Limitations. Abstract: The...

  7. Theoretical Modelling of Magnetic Refrigeration Materials A PhD studentship is available in the Warwick Theory Group on a theoretical/computational PhD project

    E-Print Network [OSTI]

    Low, Robert

    materials. The project will involve condensed matter physics theory, high performance computingTheoretical Modelling of Magnetic Refrigeration Materials A PhD studentship is available in the Warwick Theory Group on a theoretical/computational PhD project on the modelling of magnetic refrigeration

  8. Model-Experimental Studies on Next-generation Li-ion Materials...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    More Documents & Publications Performance and Degradation Modeling of Batteries Improved Methods for Making Intermetallic Anodes Overview of Applied Battery Research...

  9. Development of an atmospheric aerosol model for studies of global budgets and effects of airborne particulate material

    SciTech Connect (OSTI)

    Giorgi, F.

    1986-01-01T23:59:59.000Z

    A microphysics-removal Atmospheric Aerosol Model (AAM) is developed for use in General Circulation Models (GCM) to study global budgets and effects of particulate material. In this model the particle population is assumed to be composed of a set of log-normal modes whose time evolution due to microphysical processes is described via prognostic equations for an appropriate number of moments of the particle size distribution. This newly devised technique, by making use of a small number of prognostic equations for the aerosol variables and utilizing optimized numerical procedures, renders the model computationally efficient, hence particularly suitable for use in complex 3D GCMs. Detailed parameterizations of particle coagulation, sedimentation, dry deposition, and wet removal are incorporated into the AAM.

  10. Critical Material Parameters for Modeling Devices Made from an Epoxy-Based Shape Memory Polymer

    E-Print Network [OSTI]

    Erel, Veysel

    2014-06-17T23:59:59.000Z

    sandwiched with a thermocouple between them, the temperature curve shows that 90 minutes is more than sufficient time to complete heat a single specimen to the test temperature............................ 45 ix 34 High temperature tensile test... for Testing and Materials DIC Digital Image Correlation DMA Dynamic Mechanical Analysis DSC Differential Scanning Calorimetry FEA Finite Element...

  11. Vehicle Technologies Office Merit Review 2014: Atomistic models of LMRNMC Materials

    Broader source: Energy.gov [DOE]

    Presentation given by Argonne National Laboratory at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about atomistic models...

  12. Modeling Granular Materials as Compressible Non-Linear Fluids: Heat Transfer Boundary Value Problems

    SciTech Connect (OSTI)

    Massoudi, M.C.; Tran, P.X.

    2006-01-01T23:59:59.000Z

    We discuss three boundary value problems in the flow and heat transfer analysis in flowing granular materials: (i) the flow down an inclined plane with radiation effects at the free surface; (ii) the natural convection flow between two heated vertical walls; (iii) the shearing motion between two horizontal flat plates with heat conduction. It is assumed that the material behaves like a continuum, similar to a compressible nonlinear fluid where the effects of density gradients are incorporated in the stress tensor. For a fully developed flow the equations are simplified to a system of three nonlinear ordinary differential equations. The equations are made dimensionless and a parametric study is performed where the effects of various dimensionless numbers representing the effects of heat conduction, viscous dissipation, radiation, and so forth are presented.

  13. Unsteady-state material balance model for a continuous rotary dissolver

    SciTech Connect (OSTI)

    Lewis, B.E.

    1984-09-01T23:59:59.000Z

    The unsteady-state continuous rotary dissolver material balance code (USSCRD) is a useful tool with which to study the performance of the rotary dissolver under a wide variety of operating conditions. The code does stepwise continuous material balance calculations around each dissolver stage and the digester tanks. Output from the code consists of plots and tabular information on the stagewise concentration profiles of UO{sub 2}, PuO{sub 2}, fission products, Pu(NO{sub 3}){sub 4}, UO{sub 2}(NO{sub 3}){sub 2}, fission product nitrates, HNO{sub 3}, H{sub 2}O, stainless steel, total particulate, and total fuel in pins. Other information about material transfers, stagewise liquid volume, material inventory, and dissolution performance is also provided. This report describes the development of the code, its limitations, key operating parameters, usage procedures, and the results of the analysis of several sets of operating conditions. Of primary importance in this work was the estimation of the steady-state heavy metal inventory in a 0.5-t/d dissolver drum. Values ranging from {similar_to}12 to >150 kg of U + Pu were obtained for a variety of operating conditions. Realistically, inventories are expected to be near the lower end of this range. Study of the variation of operating parameters showed significant effects on dissolver product composition from intermittent solids feed. Other observations indicated that the cycle times for the digesters and shear feed should be closely coupled in order to avoid potential problems with off-specification product. 19 references, 14 tables.

  14. Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms: Tools for Physics-Based Model Development.

    SciTech Connect (OSTI)

    Kearney, Sean P.; Jilek, Brook Anton; Kohl, Ian Thomas; Farrow, Darcie; Urayama, Junji

    2014-11-01T23:59:59.000Z

    We present the results of an LDRD project to develop diagnostics to perform fundamental measurements of material properties during shock compression of condensed phase materials at micron spatial scales and picosecond time scales. The report is structured into three main chapters, which each focus on a different diagnostic devel opment effort. Direct picosecond laser drive is used to introduce shock waves into thin films of energetic and inert materials. The resulting laser - driven shock properties are probed via Ultrafast Time Domain Interferometry (UTDI), which can additionally be used to generate shock Hugoniot data in tabletop experiments. Stimulated Raman scattering (SRS) is developed as a temperature diagnostic. A transient absorption spectroscopy setup has been developed to probe shock - induced changes during shock compressio n. UTDI results are presented under dynamic, direct - laser - drive conditions and shock Hugoniots are estimated for inert polystyrene samples and for the explosive hexanitroazobenzene, with results from both Sandia and Lawrence Livermore presented here. SRS a nd transient absorption diagnostics are demonstrated on static thin - film samples, and paths forward to dynamic experiments are presented.

  15. Project Profile: Predictive Physico-Chemical Modeling of Intrinsic Degradation Mechanisms for Advanced Reflector Materials

    Broader source: Energy.gov [DOE]

    NREL, under the Physics of Reliability: Evaluating Design Insights for Component Technologies in Solar (PREDICTS) Program will be developing a physics-based computational degradation model to assess the kinetic oxidation rates; realistic model light attenuation and transport; and multi-layer treatment with variable properties Simulation based experimental design.

  16. Rheological constitutive equation for a model of soft glassy materials Peter Sollich*

    E-Print Network [OSTI]

    Sollich, Peter

    exactly and describe in detail a simplified scalar model for the low frequency shear rheology of foams , with a glass transition occurring at x51 ~in appropriate units!. The exact solution of the model takes the form as v x21 for 1,x,2 , becoming flat near the glass transition. In the glass phase, aging of the moduli

  17. Rheological constitutive equation for a model of soft glassy materials Peter Sollich*

    E-Print Network [OSTI]

    Sollich, Peter

    exactly and describe in detail a simplified scalar model for the low frequency shear rheology of foams, with a glass transition occurring at x 1 in appropriate units . The exact solution of the model takes the form 1 for 1 x 2, becoming flat near the glass transition. In the glass phase, aging of the moduli

  18. Porous Materials Porous Materials

    E-Print Network [OSTI]

    Berlin,Technische Universität

    1 Porous Materials x Porous Materials · Physical properties * Characteristic impedance p = p 0 e -jk xa- = vej[ ] p x - j ; Zc= p ve = c ka 0k = c 1-j #12;2 Porous Materials · Specific acoustic impedance Porous Materials · Finite thickness ­ blocked p e + -jk (x-d)a p e - jk (x-d)a d x #12

  19. Development of an atmospheric aerosol model for studies of global budgets and effects of airborne particulate material

    SciTech Connect (OSTI)

    Giorgi, F.

    1986-01-01T23:59:59.000Z

    A microphysics-removal atmospheric aerosol model (AAM) is developed for use in general circulation models (GCMs) to study global budgets and effects of particulate material. In this model the particle population is composed of a set of log-normal modes whose time evolution due to microphysical processes is described via prognostic equations for an appropriate number of moments of the particle-size distribution. Detailed parameterizations of particle coagulation, sedimentation, dry deposition, and wet removal are developed and implemented into the AAM. The AAM is incorporated into a GCM and is applied to two types of studies: (1) characteristics of the particle wet and dry removal processes, and (2) climatic impact of massive particulate injections following a global nuclear war, with emphasis on the sensitivity of the simulated effects to the inclusion of particle microphysics. Results are discussed.

  20. Helium pressures in RHIC vacuum cryostats and relief valve requirements from magnet cooling line failure

    SciTech Connect (OSTI)

    Liaw, C.J.; Than, Y.; Tuozzolo, J.

    2011-03-28T23:59:59.000Z

    A catastrophic failure of the RHIC magnet cooling lines, similar to the LHC superconducting bus failure incident, would pressurize the insulating vacuum in the magnet and transfer line cryostats. Insufficient relief valves on the cryostats could cause a structural failure. A SINDA/FLUINT{reg_sign} model, which simulated the 4.5K/4 atm helium flowing through the magnet cooling system distribution lines, then through a line break into the vacuum cryostat and discharging via the reliefs into the RHIC tunnel, had been developed to calculate the helium pressure inside the cryostat. Arc flash energy deposition and heat load from the ambient temperature cryostat surfaces were included in the simulations. Three typical areas: the sextant arc, the Triplet/DX/D0 magnets, and the injection area, had been analyzed. Existing relief valve sizes were reviewed to make sure that the maximum stresses, caused by the calculated maximum pressures inside the cryostats, did not exceed the allowable stresses, based on the ASME Code B31.3 and ANSYS results. The conclusions are as follows: (1) The S/F simulation results show that the highest internal pressure in the cryostats, due to the magnet line failure, is {approx}37 psig (255115 Pa); (2) Based on the simulation, the temperature on the cryostat chamber, INJ Q8-Q9, could drop to 228 K, which is lower than the material minimum design temperature allowed by the Code; (3) Based on the ASME Code and ANSYS results, the reliefs on all the cryostats inside the RHIC tunnel are adequate to protect the vacuum chambers when the magnet cooling lines fail; and (4) In addition to the pressure loading, the thermal deformations, due to the temperature decrease on the cryostat chambers, could also cause a high stress on the chamber, if not properly supported.

  1. Real-Time Quantitative Imaging of Failure Events in Materials...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Monday, 25 March 2013 00:00 Gathering information on the evolution of small cracks in ceramic matrix composites used in hostile environments such as in gas turbines and...

  2. Development of Apple Workgroup Cluster and Parallel Computing for Phase Field Model of Magnetic Materials

    E-Print Network [OSTI]

    Huang, Yongxin

    2010-01-16T23:59:59.000Z

    Micromagnetic modeling numerically solves magnetization evolution equation to process magnetic domain analysis, which helps to understand the macroscopic magnetic properties of ferromagnets. To apply this method in simulation of magnetostrictive...

  3. Nonlinear Rate-Dependent Material Model with Damage and Plasticity from Granular Micromechanics Approach

    E-Print Network [OSTI]

    Singh, Viraj

    2014-05-31T23:59:59.000Z

    based and ignores the effect of microstructural changes on the overall mechanical behavior. Therefore, to overcome the limitation of phenomenological based models, we utilize granular micromechanics approach in conjunction with thermo...

  4. Velocity models, material balance and solution convergence in streamline-based simulation

    E-Print Network [OSTI]

    Sabir, Kamran

    2002-01-01T23:59:59.000Z

    FOR THE QUARTER FIVE-SPOT PATTERN . . . . . . . . 2. 1 Introduction . . 2. 2 Five-Spot Waterflooding Pattern. . . . . III VELOCITY MODELS IN RECTANGULAR AND CORNER POINT CELLS . . 17 3. 1 Inn oduction1 3. 2 Literature Survey 1 . 3. 3 Velocity Models... . . . . . . . . . . . . APPENDIX A . . . . . . . . . . . . . VITA 148 150 153 158 LIST OF FIGURES FIGURE Page 2. 1 The 3D view of the pressure distribution in the quarter five-spot waterflooding pattern . 10 2. 2 The contour plot of the pressure (or potential...

  5. Effects of Fusion Zone Size and Failure Mode on Peak Load and Energy Absorption of Advanced High Strength Steel Spot Welds

    SciTech Connect (OSTI)

    Sun, Xin; Stephens, Elizabeth V.; Khaleel, Mohammad A.

    2007-01-01T23:59:59.000Z

    This paper examines the effects of fusion zone size on failure modes, static strength and energy absorption of resistance spot welds (RSW) of advanced high strength steels (AHSS). DP800 and TRIP800 spot welds are considered. The main failure modes for spot welds are nugget pullout and interfacial fracture. Partial interfacial fracture is also observed. The critical fusion zone sizes to ensure nugget pull-out failure mode are developed for both DP800 and TRIP800 using limit load based analytical model and micro-hardness measurements of the weld cross sections. Static weld strength tests using cross tension samples were performed on the joint populations with controlled fusion zone sizes. The resulted peak load and energy absorption levels associated with each failure mode were studied for all the weld populations using statistical data analysis tools. The results in this study show that AHSS spot welds with fusion zone size of can not produce nugget pullout mode for both the DP800 and TRIP800 materials examined. The critical fusion zone size for nugget pullout shall be derived for individual materials based on different base metal properties as well as different heat affected zone (HAZ) and weld properties resulted from different welding parameters.

  6. A model for prediction of the damage and effects of explosive projectiles on helicopter composite material rotor blades

    E-Print Network [OSTI]

    Mikel, Tilden Newton

    1982-01-01T23:59:59.000Z

    . The dame, ge is based on a 23-mm HEI-T projectile impacting a fiberglass rotor blade spar. The extent of damage is developed as a function of impact velocity, obliquity of the shotline, location of the impact point, and the time of fuse functioning... Projectiles on Helicopter Composite Material Rotor Blades. (December 1982) Tilden Newton Nikel, B. S. , Texas AAM University; N . S . , Texas A&N University Chairman of Advisory Committee: Dr. Clarence L. Hough Jr. A number of damage models have been...

  7. A full-spectral Bayesian reconstruction approach based on the material decomposition model applied in dual-energy computed tomography

    SciTech Connect (OSTI)

    Cai, C. [CEA, LIST, 91191 Gif-sur-Yvette, France and CNRS, SUPELEC, UNIV PARIS SUD, L2S, 3 rue Joliot-Curie, 91192 Gif-sur-Yvette (France)] [CEA, LIST, 91191 Gif-sur-Yvette, France and CNRS, SUPELEC, UNIV PARIS SUD, L2S, 3 rue Joliot-Curie, 91192 Gif-sur-Yvette (France); Rodet, T.; Mohammad-Djafari, A. [CNRS, SUPELEC, UNIV PARIS SUD, L2S, 3 rue Joliot-Curie, 91192 Gif-sur-Yvette (France)] [CNRS, SUPELEC, UNIV PARIS SUD, L2S, 3 rue Joliot-Curie, 91192 Gif-sur-Yvette (France); Legoupil, S. [CEA, LIST, 91191 Gif-sur-Yvette (France)] [CEA, LIST, 91191 Gif-sur-Yvette (France)

    2013-11-15T23:59:59.000Z

    Purpose: Dual-energy computed tomography (DECT) makes it possible to get two fractions of basis materials without segmentation. One is the soft-tissue equivalent water fraction and the other is the hard-matter equivalent bone fraction. Practical DECT measurements are usually obtained with polychromatic x-ray beams. Existing reconstruction approaches based on linear forward models without counting the beam polychromaticity fail to estimate the correct decomposition fractions and result in beam-hardening artifacts (BHA). The existing BHA correction approaches either need to refer to calibration measurements or suffer from the noise amplification caused by the negative-log preprocessing and the ill-conditioned water and bone separation problem. To overcome these problems, statistical DECT reconstruction approaches based on nonlinear forward models counting the beam polychromaticity show great potential for giving accurate fraction images.Methods: This work proposes a full-spectral Bayesian reconstruction approach which allows the reconstruction of high quality fraction images from ordinary polychromatic measurements. This approach is based on a Gaussian noise model with unknown variance assigned directly to the projections without taking negative-log. Referring to Bayesian inferences, the decomposition fractions and observation variance are estimated by using the joint maximum a posteriori (MAP) estimation method. Subject to an adaptive prior model assigned to the variance, the joint estimation problem is then simplified into a single estimation problem. It transforms the joint MAP estimation problem into a minimization problem with a nonquadratic cost function. To solve it, the use of a monotone conjugate gradient algorithm with suboptimal descent steps is proposed.Results: The performance of the proposed approach is analyzed with both simulated and experimental data. The results show that the proposed Bayesian approach is robust to noise and materials. It is also necessary to have the accurate spectrum information about the source-detector system. When dealing with experimental data, the spectrum can be predicted by a Monte Carlo simulator. For the materials between water and bone, less than 5% separation errors are observed on the estimated decomposition fractions.Conclusions: The proposed approach is a statistical reconstruction approach based on a nonlinear forward model counting the full beam polychromaticity and applied directly to the projections without taking negative-log. Compared to the approaches based on linear forward models and the BHA correction approaches, it has advantages in noise robustness and reconstruction accuracy.

  8. Modeling Different Failure Mechanisms in Metals

    E-Print Network [OSTI]

    Zhang, Liang

    2012-02-14T23:59:59.000Z

    be expressed in the Voigt notation as (2.4) The effective plastic strain increment, , can be expressed as [86] (2.5) 16 where denotes the formal inverse of . is related to by [86] (2.6) Eqs. (2.3) and (2.5) provide an appropriate measure....10) Eq. (2.10) can be formally inverted to (2.11) Eq. (2.11) can be rewritten in terms of the principal components as (2.12) Assume the out-of-plane stresses to vanish. This implies that and , where denotes the mean stress. Eq. (2.12) can...

  9. A comparison of current models for nonlinear rate-dependent material behavior of crystalline solids

    E-Print Network [OSTI]

    Beek, Joachim Michael

    1986-01-01T23:59:59.000Z

    a ss 69 83 Fig. 16 Experimental constant strain rate tensile test response. 89 Fig. 17 Experimental creep test response. . . 91 Fig. 18 Graph of in(c ) v. in~a-a) for Krieg's i l model 93 Fig. 19 Graph of Y v. a for Bodner 's model. ~ . 97... as second order tensor s, they may be tensors of' other rank as well C13]. The method of Coleman and Noll L1 0] may be used to obtain the spatial and time distribution of the body force f. and the heat supply r from the conservation of linear 1...

  10. Progress In Electromagnetics Research B, Vol. 15, 197215, 2009 MODELING OF SHIELDING COMPOSITE MATERIALS

    E-Print Network [OSTI]

    Koledintseva, Marina Y.

    Progress In Electromagnetics Research B, Vol. 15, 197­215, 2009 MODELING OF SHIELDING COMPOSITE B. Archambeault IBM Co. Research Triangle Park, NC, USA Abstract--Composites containing conducting structures are studied, with both absorbing and reflecting composite layers. In this paper, fiber

  11. Modeling of the Properties and Processing of Amorphous Gate Stacks on High Electron Mobility Materials

    E-Print Network [OSTI]

    Kummel, Andrew C.

    of their defects, simply do not exist. Further, there are no techniques which give the precise bonding structure diffusion of the semiconductor into the oxide? The role of the passivation layer is a key issue which/oxide interfaces and minimize diffusion into the oxide? d. Can we model the C-V and phonon coupling as a function

  12. The Transition-Zone Water Filter Model for Global Material Circulation: Where Do We Stand?

    E-Print Network [OSTI]

    with a small melt fraction, highly incompatible elements including hydro- gen, helium and argon are sequestered the fraction of water is small. Models have been developed to understand the structure of a melt layer Hilst, et al., 1997]), then the whole mantle is depleted with only a small volume (~10%) of relatively

  13. Development, parameterization, and validation of a visco-plastic material model for sand with different

    E-Print Network [OSTI]

    Grujicic, Mica

    the detonation products, mine fragments and soil ejecta Corresponding author: Department of Mechanical Engineer of Mechanical Engineering, Clemson University, Clemson, South Carolina, USA 2 Army Research Laboratory for sand with different levels of saturation tested mechanically at different strain rates.The model

  14. RELAP5 Model of a Two-phase ThermoSyphon Experimental Facility for Fuels and Materials Irradiation

    SciTech Connect (OSTI)

    Carbajo, Juan J [ORNL] [ORNL; McDuffee, Joel Lee [ORNL] [ORNL

    2013-01-01T23:59:59.000Z

    The High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) does not have a separate materials-irradiation flow loop and requires most materials and all fuel experiments to be placed inside a containment. This is necessary to ensure that internal contaminants such as fission products cannot be released into the primary coolant. As part of the safety basis justification, HFIR also requires that all experiments be able to withstand various accident conditions (e.g., loss of coolant) without generating vapor bubbles on the surface of the experiment in the primary coolant. As with any parallel flow system, HFIR is vulnerable to flow excursion events when vapor is generated in one of those flow paths. The effects of these requirements are to artificially increase experiment temperatures by introducing a barrier between the experimental materials and the HFIR coolant and to reduce experiment heat loads to ensure boiling doesn t occur. A new experimental facility for materials irradiation and testing in the HFIR is currently being developed to overcome these limitations. The new facility is unique in that it will have its own internal cooling flow totally independent of the reactor primary coolant and boiling is permitted. The reactor primary coolant will cool the outside of this facility without contacting the materials inside. The ThermoSyphon Test Loop (TSTL), a full scale prototype of the proposed irradiation facility to be tested outside the reactor, is being designed and fabricated (Ref. 1). The TSTL is a closed system working as a two-phase thermosyphon. A schematic is shown in Fig. 1. The bottom central part is the boiler/evaporator and contains three electric heaters. The vapor generated by the heaters will rise and be condensed in the upper condenser, the condensate will drain down the side walls and be circulated via a downcomer back into the bottom of the boiler. An external flow system provides coolant that simulates the HFIR primary coolant. The two-phase flow code RELAP5-3D (Ref. 2) is the main tool employed in this design. The model has multiple challenges: boiling, condensation and natural convection flows need to be modeled accurately.

  15. Near-Optimal Distributed Failure Circumscription

    E-Print Network [OSTI]

    Beal, Jacob

    2003-08-11T23:59:59.000Z

    Small failures should only disrupt a small part of a network. One way to do this is by marking the surrounding area as untrustworthy --- circumscribing the failure. This can be done with a distributed algorithm using ...

  16. Near-Optimal Distributed Failure Circumscription

    E-Print Network [OSTI]

    Beal, Jacob

    2003-08-11T23:59:59.000Z

    Small failures should only disrupt a small part of a network. One wayto do this is by marking the surrounding area as untrustworthy ---circumscribing the failure. This can be done with a distributedalgorithm using ...

  17. Optimization Online - Constraint Qualification Failure in Second ...

    E-Print Network [OSTI]

    Hassan L. Hijazi

    2014-07-22T23:59:59.000Z

    Jul 22, 2014 ... ... Qualification Failure in Second-Order Cone Formulations of Unbounded Disjunctions" Technical Report - NICTA, Canberra ACT Australia, ...

  18. Solar Energy Materials & Solar Cells 92 (2008) 821829 Modeling the optical properties of WO3 and WO3SiO2 thin films

    E-Print Network [OSTI]

    Thirumalai, Devarajan

    Solar Energy Materials & Solar Cells 92 (2008) 821­829 Modeling the optical properties of WO3 the optical response of the films in the near-UV and visible region: two interband transitions for energies E

  19. Thermo-Viscoelastic-Viscoplastic-Viscodamage-Healing Modeling of Bituminous Materials: Theory and Computation

    E-Print Network [OSTI]

    Darabi Konartakhteh, Masoud

    2012-10-19T23:59:59.000Z

    ……………… ……… 341 9.6. Extrapolation of the Rutting in 3D.……....………… 348 9.7. Comparison with Experimental Results.….………… 351 9.8. Conclusions………………………………………… 354 xviii CHAPTER Page X CONCLUSIONS AND RECOMMENDATIONS..…………… 356 10... prediction using viscoelastic- viscoplastic model and experimental data for the cyclic stress control test at 19oC when the stress amplitude is 750kPa. (a) Loading cycles 1-30; (b) Loading cycles 970-980……………….. 268 7.36 Comparison of the VE...

  20. Systems Modeling of Chemical Hydride Hydrogen Storage Materials for Fuel Cell Applications

    SciTech Connect (OSTI)

    Brooks, Kriston P.; Devarakonda, Maruthi N.; Rassat, Scot D.; Holladay, Jamelyn D.

    2011-10-05T23:59:59.000Z

    A fixed bed reactor was designed, modeled and simulated for hydrogen storage on-board the vehicle for PEM fuel cell applications. Ammonia Borane (AB) was selected by DOE's Hydrogen Storage Engineering Center of Excellence (HSECoE) as the initial chemical hydride of study because of its high hydrogen storage capacity (up to {approx}16% by weight for the release of {approx}2.5 molar equivalents of hydrogen gas) and its stability under typical ambient conditions. The design evaluated consisted of a tank with 8 thermally isolated sections in which H2 flows freely between sections to provide ballast. Heating elements are used to initiate reactions in each section when pressure drops below a specified level in the tank. Reactor models in Excel and COMSOL were developed to demonstrate the proof-of-concept, which was then used to develop systems models in Matlab/Simulink. Experiments and drive cycle simulations showed that the storage system meets thirteen 2010 DOE targets in entirety and the remaining four at greater than 60% of the target.

  1. The Heart Failure Bridge Clinic Quality

    E-Print Network [OSTI]

    von der Heydt, Rüdiger

    The Heart Failure Bridge Clinic Quality Improvement Project My project involved working with my mentor, Tasha Beck Freitag, CRNP, MPH, CHFN, and loosely with Deirdre Flowers, MSN-MPH, who is the heart failure case manager. The heart failure bridge clinic (HFBC), is a standalone clinic that was created

  2. Failure prognostic by using Dynamic Bayesian Networks

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    to failures and their maintenance ex- pensive. To keep them in good operational conditions, maintenance to the ISO standard (ISO, 13381-1 (2004)), failure prognostic corresponds to the estimation of the operating presents a procedure for failure prognostic by using Dynamic Bayesian Networks (DBNs). The graphical

  3. Dissimilar-metal weld failures in boiler tubing

    SciTech Connect (OSTI)

    Klueh, R.L.

    1984-02-01T23:59:59.000Z

    Both ferritic heat-resisting steels and austenitic stainless steels are used for fossil-fired boilers for central power stations. The use of these two different types of materials within the system leads to the need for a dissimilar-metal weld transition joint. Increased cyclic operation of boilers has led to a rash of failures in welds between dissimilar metals; studies have identified the causes, and improved nondestructive testing techniques permit early identification of problem areas.

  4. GROUND PLANE INSULATION FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

    is WIUUTEO GROUND PLANE INSULATION FAILURE IN THE FIRST TPCOn August 27, 1980, an insulation failure occurred dt-ringby a failure uf ground plane insulation. ACKNOWLEDGMENTS The

  5. Power Grid Defense Against Malicious Cascading Failure

    E-Print Network [OSTI]

    Shakarian, Paulo; Lindelauf, Roy

    2014-01-01T23:59:59.000Z

    An adversary looking to disrupt a power grid may look to target certain substations and sources of power generation to initiate a cascading failure that maximizes the number of customers without electricity. This is particularly an important concern when the enemy has the capability to launch cyber-attacks as practical concerns (i.e. avoiding disruption of service, presence of legacy systems, etc.) may hinder security. Hence, a defender can harden the security posture at certain power stations but may lack the time and resources to do this for the entire power grid. We model a power grid as a graph and introduce the cascading failure game in which both the defender and attacker choose a subset of power stations such as to minimize (maximize) the number of consumers having access to producers of power. We formalize problems for identifying both mixed and deterministic strategies for both players, prove complexity results under a variety of different scenarios, identify tractable cases, and develop algorithms f...

  6. An Instability Leading to Failure of Polyethylene in Uniaxial Creep

    E-Print Network [OSTI]

    An Instability Leading to Failure of Polyethylene in Uniaxial Creep L. J. ZAPAS and J. M. CRISSMAN model, a point of instability is pre- dicted for the uniaxial creep of high density polyethylene. From dead load experiments it has been found that the instabil- ity occurs for linear -polyethylene

  7. Micromechanical simulation of the failure of ber reinforced composites

    E-Print Network [OSTI]

    Micromechanical simulation of the failure of ®ber reinforced composites Chad M. Landisa, *, Irene J Abstract The strength of unidirectionally reinforced ®ber composites is simulated using the three lag model for broken ®bers in composites. J. Comp. Mat. 33, 667±680) and Weibull ®ber statistics

  8. Queueing systems subject to random server failures: an approximation

    E-Print Network [OSTI]

    Matis, Timothy

    1998-01-01T23:59:59.000Z

    In the traditional study of queueing theory, a typical ics. assumption is that the server is not subject to failures. This assumption, however, is not realistic for modeling many queueing systems in practice. Since the late 1950's, there has been...

  9. Modeling of material and energy flow in an EBCHR casting system

    SciTech Connect (OSTI)

    Westerberg, K.W. [Aspen Technology, Inc., Cambridge, MA (United States); McClelland, M.A. [Lawrence Livermore National Lab., CA (United States)

    1994-11-01T23:59:59.000Z

    A numerical and experimental analysis is made of fluid flow and heat transfer in a continuous casting system with an electron-beam energy source. For a cylindrical ingot confined in a water-cooled crucible, a two-dimensional, steady-state model is developed which includes the effects of free convection in the pool and conduction in the two-phase and solid regions. A modified Galerkin finite element method is used to solve for the flow and temperature fields simultaneously with the upper and lower boundaries of the pool. The calculation grid deforms along vertical spines as these phase boundaries move. Heat flows are measured in a steady-state experiment involving a short ingot and no pouring. Heat transfer coefficients representing contact resistance are determined, and measured heat flows are compared with model values. Flow and temperature fields along with solidification-zone boundaries are calculated for the experimental case and a case in which the ingot cooling is improved.

  10. Modeling of material and energy flow in an EBCHR casting system

    SciTech Connect (OSTI)

    Westerberg, K.W. [Aspen Technology, Inc., Cambridge, MA (United States); McClelland, M.A. [Lawrence Livermore National Lab., CA (United States)

    1994-12-31T23:59:59.000Z

    A numerical and experimental analysis is made of fluid flow and heat transfer in a continuous casting system with an electron-beam energy source. For a cylindrical ingot confined in a water-cooled crucible, a two-dimensional, steady-state model is developed which includes the effects of free convection in the pool and conduction in the two-phase and solid regions. A modified Galerkin finite element method is used to solve for the flow and temperature fields simultaneously with the upper and lower boundaries of the pool. The calculation grid deforms along vertical spines as these phase boundaries move. Heat flows are measured in a steady-state experiment involving a short ingot and no pouring. Heat transfer coefficients representing contact resistance are determined, and measured heat flows are compared with model values. Flow and temperature fields along with solidification-zone boundaries are calculated for the experimental case and a case in which the ingot cooling is improved.

  11. Original article Increased late sodium current in myocytes from a canine heart failure

    E-Print Network [OSTI]

    Kamp, Tim

    Original article Increased late sodium current in myocytes from a canine heart failure model and from failing human heart Carmen R. Valdivia, William W. Chu, Jielin Pu 1 , Jason D. Foell, Robert A December 2004 Abstract Electrophysiological remodeling of ion channels in heart failure causes action

  12. An Automatic Failure Mode and Effect Analysis Technique for Processes Defined in the Little-JIL

    E-Print Network [OSTI]

    Avrunin, George S.

    Failure Mode and Effect Analysis (FMEA) information from processes modeled in the Little-JIL process definition language. Typically FMEA information is created manually by skilled experts, an approach this definition can then be used to create FMEA representations for a wide range of potential failures

  13. Global Failure Criteria for SOFC Positive/Electrolyte/Negative (PEN) Structure

    SciTech Connect (OSTI)

    Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.; Qu, Jianmin

    2007-04-01T23:59:59.000Z

    Due to the mismatch of thermal expansion coefficients (TEC) of the various layer materials in SOFC, the internal stresses are unavoidable under temperature differential. In order to create the reliable cell and stack of solid oxide fuel cell (SOFC), it is necessary to develop a failure criterion for SOFC PEN structures for the initial failures occurred during cell/stack assembly. In this paper, a global failure criterion is developed for the initial design against mechanical failure of the PEN structure in high temperature SOFCs. The relationship of the critical energy release rate and critical curvature and maximum displacement of the warpage of the cells caused by the temperature differential is established so that the failure reliability of SOFC PEN structures may be determined by the measurement of the curvature and displacement of the warpaged cells.

  14. Test to Determine Margin-to-Failure for Hy-100 Steel with Undermatched Welds

    SciTech Connect (OSTI)

    K.R. Arpin; T.F. Trimble

    2003-04-01T23:59:59.000Z

    This test program was undertaken to determine the flaw tolerance and to quantify the strength margin-to-failure of high yield strength steel fillet welded specimens. The tests demonstrate adequate margin-to-failure for HY-100 specimens fabricated with matched welding systems. In the use of high yield (HY) steel materials in designs required to accommodate rapidly applied dynamic loads, the concern was raised where the possibility of decreased flaw tolerance and premature failure by unstable ductile tearing could limit their use. Tests were developed and conducted to demonstrate adequate margin-to-failure in HY-100 fillet and partial penetration welded structures. In addition, inelastic analytical predictions were performed to assess the accuracy of such predictive tools compared to actual test data. Results showed that adequate margin-to-failure exists when using matched welding systems.

  15. Thermal performance sensitivity studies in support of material modeling for extended storage of used nuclear fuel

    SciTech Connect (OSTI)

    Cuta, Judith M.; Suffield, Sarah R.; Fort, James A.; Adkins, Harold E.

    2013-08-15T23:59:59.000Z

    The work reported here is an investigation of the sensitivity of component temperatures of a storage system, including fuel cladding temperatures, in response to age-related changes that could degrade the design-basis thermal behavior of the system. Three specific areas of interest were identified for this study. • degradation of the canister backfill gas from pure helium to a mixture of air and helium, resulting from postulated leakage due to stress corrosion cracking (SCC) of canister welds • changes in surface emissivity of system components, resulting from corrosion or other aging mechanisms, which could cause potentially significant changes in temperatures and temperature distributions, due to the effect on thermal radiation exchange between components • changes in fuel and basket temperatures due to changes in fuel assembly position within the basket cells in the canister The purpose of these sensitivity studies is to provide a realistic example of how changes in the physical properties or configuration of the storage system components can affect temperatures and temperature distributions. The magnitudes of these sensitivities can provide guidance for identifying appropriate modeling assumptions for thermal evaluations extending long term storage out beyond 50, 100, 200, and 300 years.

  16. Identification and Assessment of Material Models for Age-Related Degradation of Structures and Passive Components in Nuclear Power Plants

    SciTech Connect (OSTI)

    Nie,J.; Braverman, J.; Hofmayer, C.; Kim, M. K.; Choi, I-K.

    2009-04-27T23:59:59.000Z

    When performing seismic safety assessments of nuclear power plants (NPPs), the potential effects of age-related degradation on structures, systems, and components (SSCs) should be considered. To address the issue of aging degradation, the Korea Atomic Energy Research Institute (KAERI) has embarked on a five-year research project to develop a realistic seismic risk evaluation system which will include the consideration of aging of structures and components in NPPs. Three specific areas that are included in the KAERI research project, related to seismic probabilistic risk assessment (PRA), are probabilistic seismic hazard analysis, seismic fragility analysis including the effects of aging, and a plant seismic risk analysis. To support the development of seismic capability evaluation technology for degraded structures and components, KAERI entered into a collaboration agreement with Brookhaven National Laboratory (BNL) in 2007. The collaborative research effort is intended to continue over a five year period with the goal of developing seismic fragility analysis methods that consider the potential effects of age-related degradation of SSCs, and using these results as input to seismic PRAs. In the Year 1 scope of work BNL collected and reviewed degradation occurrences in US NPPs and identified important aging characteristics needed for the seismic capability evaluations that will be performed in the subsequent evaluations in the years that follow. This information is presented in the Annual Report for the Year 1 Task, identified as BNL Report-81741-2008 and also designated as KAERI/RR-2931/2008. The report presents results of the statistical and trending analysis of this data and compares the results to prior aging studies. In addition, the report provides a description of U.S. current regulatory requirements, regulatory guidance documents, generic communications, industry standards and guidance, and past research related to aging degradation of SSCs. This report describes the research effort performed by BNL for the Year 2 scope of work. This research focused on methods that could be used to represent the long-term behavior of materials used at NPPs. To achieve this BNL reviewed time-dependent models which can approximate the degradation effects of the key materials used in the construction of structures and passive components determined to be of interest in the Year 1 effort. The intent was to review the degradation models that would cover the most common time-dependent changes in material properties for concrete and steel components.

  17. Contact method to allow benign failure in ceramic capacitor having self-clearing feature

    DOE Patents [OSTI]

    Myers, John D.; Taylor, Ralph S.

    2012-06-26T23:59:59.000Z

    A capacitor exhibiting a benign failure mode has a first electrode layer, a first ceramic dielectric layer deposited on a surface of the first electrode, and a second electrode layer disposed on the ceramic dielectric layer, wherein selected areas of the ceramic dielectric layer have additional dielectric material of sufficient thickness to exhibit a higher dielectric breakdown voltage than the remaining majority of the dielectric layer. The added thickness of the dielectric layer in selected areas allows lead connections to be made at the selected areas of greater dielectric thickness while substantially eliminating a risk of dielectric breakdown and failure at the lead connections, whereby the benign failure mode is preserved.

  18. WAXS fat subtraction model to estimate differential linear scattering coefficients of fatless breast tissue: Phantom materials evaluation

    SciTech Connect (OSTI)

    Tang, Robert Y., E-mail: rx-tang@laurentian.ca [Biomolecular Sciences Program, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6 (Canada); Laamanen, Curtis, E-mail: cx-laamanen@laurentian.ca; McDonald, Nancy, E-mail: mcdnancye@gmail.com [Department of Physics, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6 (Canada)] [Department of Physics, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6 (Canada); LeClair, Robert J., E-mail: rleclair@laurentian.ca [Department of Physics, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6, Canada and Biomolecular Sciences Program, Laurentian University, 935 Ramsey Lake Road, Sudbury, Ontario P3E 2C6 (Canada)

    2014-05-15T23:59:59.000Z

    Purpose: Develop a method to subtract fat tissue contributions to wide-angle x-ray scatter (WAXS) signals of breast biopsies in order to estimate the differential linear scattering coefficients ?{sub s} of fatless tissue. Cancerous and fibroglandular tissue can then be compared independent of fat content. In this work phantom materials with known compositions were used to test the efficacy of the WAXS subtraction model. Methods: Each sample 5 mm in diameter and 5 mm thick was interrogated by a 50 kV 2.7 mm diameter beam for 3 min. A 25 mm{sup 2} by 1 mm thick CdTe detector allowed measurements of a portion of the ? = 6° scattered field. A scatter technique provided means to estimate the incident spectrum N{sub 0}(E) needed in the calculations of ?{sub s}[x(E, ?)] where x is the momentum transfer argument. Values of ?{sup ¯}{sub s} for composite phantoms consisting of three plastic layers were estimated and compared to the values obtained via the sum ?{sup ¯}{sub s}{sup ?}(x)=?{sub 1}?{sub s1}(x)+?{sub 2}?{sub s2}(x)+?{sub 3}?{sub s3}(x), where ?{sub i} is the fractional volume of the ith plastic component. Water, polystyrene, and a volume mixture of 0.6 water + 0.4 polystyrene labelled as fibphan were chosen to mimic cancer, fat, and fibroglandular tissue, respectively. A WAXS subtraction model was used to remove the polystyrene signal from tissue composite phantoms so that the ?{sub s} of water and fibphan could be estimated. Although the composite samples were layered, simulations were performed to test the models under nonlayered conditions. Results: The well known ?{sub s} signal of water was reproduced effectively between 0.5 < x < 1.6 nm{sup ?1}. The ?{sup ¯}{sub s} obtained for the heterogeneous samples agreed with ?{sup ¯}{sub s}{sup ?}. Polystyrene signals were subtracted successfully from composite phantoms. The simulations validated the usefulness of the WAXS models for nonlayered biopsies. Conclusions: The methodology to measure ?{sub s} of homogeneous samples was quantitatively accurate. Simple WAXS models predicted the probabilities for specific x-ray scattering to occur from heterogeneous biopsies. The fat subtraction model can allow ?{sub s} signals of breast cancer and fibroglandular tissue to be compared without the effects of fat provided there is an independent measurement of the fat volume fraction ?{sub f}. Future work will consist of devising a quantitative x-ray digital imaging method to estimate ?{sub f} in ex vivo breast samples.

  19. Failure analysis issues in microelectromechanical systems (MEMS).

    SciTech Connect (OSTI)

    Walraven, Jeremy Allen

    2005-07-01T23:59:59.000Z

    Failure analysis and device characterization of MEMS components are critical steps in understanding the root causes of failure and improving device performance. At the wafer and die level these tasks can be performed with little or no sample preparation. Larger challenges occur after fabrication when the device is packaged, capped, sealed, or otherwise obstructed from view. The challenges and issues of MEMS failure analysis lie in identifying the root cause of failure for these packaged, capped, and sealed devices without perturbing the device or its immediate environment. Novel methods of gaining access to the device or preparing the device for analysis are crucial to accurately determining the root cause of failure. This paper will discuss issues identified in performing root cause failure analysis of packaged MEMS devices, as well as the methods employed to analyze them.

  20. Energy efficiency, market failures, and government policy

    SciTech Connect (OSTI)

    Levine, M.D.; Koomey, J.G.; McMahon, J.E.; Sanstad, A.H. [Lawrence Berkeley Lab., CA (United States). Energy and Environment Div.; Hirst, E. [Oak Ridge National Lab., TN (United States). Energy Div.

    1994-03-01T23:59:59.000Z

    This paper presents a framework for evaluating engineering-economic evidence on the diffusion of energy efficiency improvements. Four examples are evaluated within this framework. The analysis provides evidence of market failures related to energy efficiency. Specific market failures that may impede the adoption of cost-effective energy efficiency are discussed. Two programs that have had a major impact in overcoming these market failures, utility DSM programs and appliance standards, are described.

  1. Addressing Failures in Exascale Computing

    SciTech Connect (OSTI)

    Snir, Marc [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); Wisniewski, Robert [Intel Corporation] [Intel Corporation; Abraham, Jacob [unknown] [unknown; Adve, Sarita [University of Illinois, Urbana-Champaign] [University of Illinois, Urbana-Champaign; Bagchi, Saurabh [Purdue University] [Purdue University; Balaji, Pavan [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); Belak, J. [Lawrence Livermore National Laboratory (LLNL)] [Lawrence Livermore National Laboratory (LLNL); Bose, Pradip [IBM T. J. Watson Research Center] [IBM T. J. Watson Research Center; Cappello, Franck [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); Carlson, Bill [unknown] [unknown; Chien, Andrew [University of Chicago] [University of Chicago; Coteus, Paul [IBM T. J. Watson Research Center] [IBM T. J. Watson Research Center; DeBardeleben, Nathan [Los Alamos National Laboratory (LANL)] [Los Alamos National Laboratory (LANL); Diniz, Pedro [University of Southern California] [University of Southern California; Engelmann, Christian [ORNL] [ORNL; Erez, Mattan [University of Texas at Austin] [University of Texas at Austin; Fazzari, Saverio [Booz Allen Hamilton] [Booz Allen Hamilton; Geist, Al [ORNL] [ORNL; Gupta, Rinku [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); Johnson, Fred [Science Applications International Corporation (SAIC), Oak Ridge, TN] [Science Applications International Corporation (SAIC), Oak Ridge, TN; Krishnamoorthy, Sriram [Pacific Northwest National Laboratory (PNNL)] [Pacific Northwest National Laboratory (PNNL); Leyffer, Sven [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); Liberty, Dean [AMD] [AMD; Mitra, Subhasish [Stanford University] [Stanford University; Munson, Todd [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); Schreiber, Rob [HP Labs] [HP Labs; Stearley, Jon [Sandia National Laboratories (SNL)] [Sandia National Laboratories (SNL); Van Hensbergen, Eric [ARM] [ARM

    2014-01-01T23:59:59.000Z

    We present here a report produced by a workshop on Addressing failures in exascale computing' held in Park City, Utah, 4-11 August 2012. The charter of this workshop was to establish a common taxonomy about resilience across all the levels in a computing system, discuss existing knowledge on resilience across the various hardware and software layers of an exascale system, and build on those results, examining potential solutions from both a hardware and software perspective and focusing on a combined approach. The workshop brought together participants with expertise in applications, system software, and hardware; they came from industry, government, and academia, and their interests ranged from theory to implementation. The combination allowed broad and comprehensive discussions and led to this document, which summarizes and builds on those discussions.

  2. Addressing failures in exascale computing

    SciTech Connect (OSTI)

    Snir, Marc; Wisniewski, Robert W.; Abraham, Jacob A.; Adve, Sarita; Bagchi, Saurabh; Balaji, Pavan; Belak, Jim; Bose, Pradip; Cappello, Franck; Carlson, William; Chien, Andrew A.; Coteus, Paul; Debardeleben, Nathan A.; Diniz, Pedro; Engelmann, Christian; Erez, Mattan; Saverio, Fazzari; Geist, Al; Gupta, Rinku; Johnson, Fred; Krishnamoorthy, Sriram; Leyffer, Sven; Liberty, Dean; Mitra, Subhasish; Munson, Todd; Schreiber, Robert; Stearly, Jon; Van Hensbergen, Eric

    2014-05-01T23:59:59.000Z

    We present here a report produced by a workshop on “Addressing Failures in Exascale Computing” held in Park City, Utah, August 4–11, 2012. The charter of this workshop was to establish a common taxonomy about resilience across all the levels in a computing system; discuss existing knowledge on resilience across the various hardware and software layers of an exascale system; and build on those results, examining potential solutions from both a hardware and software perspective and focusing on a combined approach. The workshop brought together participants with expertise in applications, system software, and hardware; they came from industry, government, and academia; and their interests ranged from theory to implementation. The combination allowed broad and comprehensive discussions and led to this document, which summarizes and builds on those discussions.

  3. ADVANCED COMPOSITE MATERIALS TECHNOLOGY FOR ROTORCRAFT Andrew Makeev*, University of Texas at Arlington, Arlington, Texas, USA

    E-Print Network [OSTI]

    Texas at Arlington, University of

    ADVANCED COMPOSITE MATERIALS TECHNOLOGY FOR ROTORCRAFT Andrew Makeev*, University of Texas, Patz Materials & Technologies, Benicia, CA, USA Abstract Composite materials are increasingly used. In polymer-matrix composite structures, matrix-dominated failures impose severe limitations on structural

  4. Numerical modelling of sandstone uniaxial compression test using a mix-mode cohesive fracture model

    E-Print Network [OSTI]

    Gui, Yilin; Kodikara, Jayantha

    2015-01-01T23:59:59.000Z

    A mix-mode cohesive fracture model considering tension, compression and shear material behaviour is presented, which has wide applications to geotechnical problems. The model considers both elastic and inelastic displacements. Inelastic displacement comprises fracture and plastic displacements. The norm of inelastic displacement is used to control the fracture behaviour. Meantime, a failure function describing the fracture strength is proposed. Using the internal programming FISH, the cohesive fracture model is programmed into a hybrid distinct element algorithm as encoded in Universal Distinct Element Code (UDEC). The model is verified through uniaxial tension and direct shear tests. The developed model is then applied to model the behaviour of a uniaxial compression test on Gosford sandstone. The modelling results indicate that the proposed cohesive fracture model is capable of simulating combined failure behaviour applicable to rock.

  5. Opportunistically Reconstructing a Network's Failure History /

    E-Print Network [OSTI]

    Turner, Daniel Joseph

    2013-01-01T23:59:59.000Z

    to identify anomalies in datacenter applications [40]. Theytraffic data from a datacenter network [14]. They use thesethe failures in a datacenter environment. The techniques

  6. DEVELOPMENT OF PLASTICITY MODEL USING NON ASSOCIATED FLOW RULE FOR HCP MATERIALS INCLUDING ZIRCONIUM FOR NUCLEAR APPLICATIONS

    SciTech Connect (OSTI)

    Michael V. Glazoff; Jeong-Whan Yoon

    2013-08-01T23:59:59.000Z

    In this report (prepared in collaboration with Prof. Jeong Whan Yoon, Deakin University, Melbourne, Australia) a research effort was made to develop a non associated flow rule for zirconium. Since Zr is a hexagonally close packed (hcp) material, it is impossible to describe its plastic response under arbitrary loading conditions with any associated flow rule (e.g. von Mises). As a result of strong tension compression asymmetry of the yield stress and anisotropy, zirconium displays plastic behavior that requires a more sophisticated approach. Consequently, a new general asymmetric yield function has been developed which accommodates mathematically the four directional anisotropies along 0 degrees, 45 degrees, 90 degrees, and biaxial, under tension and compression. Stress anisotropy has been completely decoupled from the r value by using non associated flow plasticity, where yield function and plastic potential have been treated separately to take care of stress and r value directionalities, respectively. This theoretical development has been verified using Zr alloys at room temperature as an example as these materials have very strong SD (Strength Differential) effect. The proposed yield function reasonably well models the evolution of yield surfaces for a zirconium clock rolled plate during in plane and through thickness compression. It has been found that this function can predict both tension and compression asymmetry mathematically without any numerical tolerance and shows the significant improvement compared to any reported functions. Finally, in the end of the report, a program of further research is outlined aimed at constructing tensorial relationships for the temperature and fluence dependent creep surfaces for Zr, Zircaloy 2, and Zircaloy 4.

  7. Summary of failure analysis activities at Brookhaven National Laboratory

    SciTech Connect (OSTI)

    Cowgill, M.G.; Czajkowski, C.J.; Franz, E.M.

    1996-10-01T23:59:59.000Z

    Brookhaven National Laboratory has for many years conducted examinations related to the failures of nuclear materials and components. These examinations included the confirmation of root cause analyses, the determination of the causes of failure, identification of the species that accelerate corrosion, and comparison of the results of nondestructive examinations with those obtained by destructive examination. The results of those examinations, which had previously appeared in various formats (formal and informal reports, journal articles, etc.), have been collected together and summarized in the present report. The report is divided into sections according to the general subject matter (for example, corrosion, fatigue, etc.). Each section presents summaries of the information contained in specific reports and publications, all of which are fully identified as to title, authors, report number or journal reference, date of publication, and FIN number under which the work was performed.

  8. OPERATING EXPERIENCE LEVEL 3, Requalification Test Failure of Certain High Efficiency Particulate Air (HEPA) Filters- Update

    Broader source: Energy.gov [DOE]

    2014-01 Operating Experience Level 3 (OE-3) document provides information regarding the previous requalification test failure and subsequent successful requalification, of certain high efficiency particulate air (HEPA) filter models manufactured by Flanders Corporation.

  9. Probabilistic Hazard Assessment of Tsunamis Induced by the Translational Failure of Multiple Submarine Rigid Landslides

    E-Print Network [OSTI]

    Jimenez Martinez, Arturo

    2012-10-19T23:59:59.000Z

    A numerical study aimed at probabilistically assessing the coastal hazard posed by tsunamis induced by one-dimensional submarine rigid landslides that experience translational failure is presented. The numerical model here utilized is the finite...

  10. E-Print Network 3.0 - acute cardiac failure Sample Search Results

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    cardiac failure Page: << < 1 2 3 4 5 > >> 1 Workshop on Multi-scale Modelling of the Heart 27-29 March 2008, Auckland, New Zealand Summary: + signalling 10:40- 11:05 Overview...

  11. The Impact of Protection System Failures on Power System Reliability Evaluation

    E-Print Network [OSTI]

    Jiang, Kai

    2012-11-05T23:59:59.000Z

    The reliability of protection systems has emerged as an important topic because protection failures have critical influence on the reliability of power systems. The goal of this research is to develop novel approaches for modeling and analysis...

  12. Module Design, Materials, and Packaging Research Team: Activities and Capabilities

    SciTech Connect (OSTI)

    McMahon, T. J.; del Cueto, J.; Glick, S.; Jorgensen, G.; Kempe, M.; Kennedy, C.; Pern, J.; Terwilliger, K

    2005-01-01T23:59:59.000Z

    Our team activities are directed at improving PV module reliability by incorporating new, more effective, and less expensive packaging materials and techniques. New and existing materials or designs are evaluated before and during accelerated environmental exposure for the following properties: (1) Adhesion and cohesion: peel strength and lap shear. (2) Electrical conductivity: surface, bulk, interface and transients. (3) Water vapor transmission: solubility and diffusivity. (4) Accelerated weathering: ultraviolet, temperature, and damp heat tests. (5) Module and cell failure diagnostics: infrared imaging, individual cell shunt characterization, coring. (6) Fabrication improvements: SiOxNy barrier coatings and enhanced wet adhesion. (7) Numerical modeling: Moisture ingress/egress, module and cell performance, and cell-to-frame leakage current. (8) Rheological properties of polymer encapsulant and sheeting materials. Specific examples will be described.

  13. EMSL - battery materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    battery-materials en Modeling Interfacial Glass-Water Reactions: Recent Advances and Current Limitations. http:www.emsl.pnl.govemslwebpublicationsmodeling-interfacial-glass-wa...

  14. Reliability Failure Mode, Effects, and Criticality Analysis

    E-Print Network [OSTI]

    Rathbun, Julie A.

    Reliability Failure Mode, Effects, and Criticality Analysis Addendum 1; HFE ~ ATM501 PAGE I I. Hiebert Reliability Engineer HFE · B-1 f #12;~~.~-~ -_ ~ ~ Reliability Failure Mode, Effects were slight adjustment in the linearizing resistors. The reliability is effected upward by the deletion

  15. FAILURE DISCRIMINATION BY SEMI-DEFINITE PROGRAMMING

    E-Print Network [OSTI]

    Uryasev, Stanislav

    mining approach to cancer diagnosis [12], applied the same idea to failure discrimination for failure discriminant analysis, a classical and yet very actively studied problem in financial engineering, data-mining, support vector machine 1. Introduction Quantitative analysis of credit risk attracted more

  16. Beyond Success and Failure Sandro Etalle

    E-Print Network [OSTI]

    van Raamsdonk, Femke

    Beyond Success and Failure Sandro Etalle Dept. of Computer Science, Universiteit Maastricht P based on logic programming where success and failure are replaced by predicates for adequacy of the selection rule does not hold. We show that, under certain conditions, whenever there exists an adequate

  17. CLINICAL RESEARCH Heart failure/cardiomyopathy

    E-Print Network [OSTI]

    Duncan, James S.

    RESEARCH Heart failure/cardiomyopathy Preserved left ventricular twist and circumferential deformation, but depressed longitudinal and radial deformation in patients with diastolic heart failure Jianwen Wang, Dirar SBakey Heart Center, The Methodist Hospital, Houston, TX 77030-2717, USA Received 27 September 2007; revised 15

  18. MEMS Reliability: Infrastructure, Test Structures, Experiments, and Failure Modes

    SciTech Connect (OSTI)

    TANNER,DANELLE M.; SMITH,NORMAN F.; IRWIN,LLOYD W.; EATON,WILLIAM P.; HELGESEN,KAREN SUE; CLEMENT,J. JOSEPH; MILLER,WILLIAM M.; MILLER,SAMUEL L.; DUGGER,MICHAEL T.; WALRAVEN,JEREMY A.; PETERSON,KENNETH A.

    2000-01-01T23:59:59.000Z

    The burgeoning new technology of Micro-Electro-Mechanical Systems (MEMS) shows great promise in the weapons arena. We can now conceive of micro-gyros, micro-surety systems, and micro-navigators that are extremely small and inexpensive. Do we want to use this new technology in critical applications such as nuclear weapons? This question drove us to understand the reliability and failure mechanisms of silicon surface-micromachined MEMS. Development of a testing infrastructure was a crucial step to perform reliability experiments on MEMS devices and will be reported here. In addition, reliability test structures have been designed and characterized. Many experiments were performed to investigate failure modes and specifically those in different environments (humidity, temperature, shock, vibration, and storage). A predictive reliability model for wear of rubbing surfaces in microengines was developed. The root causes of failure for operating and non-operating MEMS are discussed. The major failure mechanism for operating MEMS was wear of the polysilicon rubbing surfaces. Reliability design rules for future MEMS devices are established.

  19. Process Considerations and Failure Analysis using Focused Ion Beam Milling

    E-Print Network [OSTI]

    Roy L. Rasera; Certifie Dr; Joseph B. Bernstein; Roy L. Rasera

    1995-01-01T23:59:59.000Z

    novel method of connecting two adjacent lines on the same level of metallization in integrated circuits using a laser was previously developed with programmable gate array applications and customized chips in mind. This work reports a study of failure mechanisms in the laser linking process. Experiments relating critical processing parameters (laser power and target alignment) to the visual failure modes were performed. A Focused Ion Beam (FIB) was used to cross-section and image failed links. The images were compared with previously published linking models. Finite element analysis was used to simulate laser absorption and subsequent thermal diffusion, and to justify a simple model defining the process window for laser linking. The research correlated theoretical predictions

  20. Analyzing Cascading Failures in Smart Grids under Random and Targeted Attacks

    E-Print Network [OSTI]

    Ruj, Sushmita

    2015-01-01T23:59:59.000Z

    We model smart grids as complex interdependent networks, and study targeted attacks on smart grids for the first time. A smart grid consists of two networks: the power network and the communication network, interconnected by edges. Occurrence of failures (attacks) in one network triggers failures in the other network, and propagates in cascades across the networks. Such cascading failures can result in disintegration of either (or both) of the networks. Earlier works considered only random failures. In practical situations, an attacker is more likely to compromise nodes selectively. We study cascading failures in smart grids, where an attacker selectively compromises the nodes with probabilities proportional to their degrees; high degree nodes are compromised with higher probability. We mathematically analyze the sizes of the giant components of the networks under targeted attacks, and compare the results with the corresponding sizes under random attacks. We show that networks disintegrate faster for targeted...

  1. MATERIALS CURRICULUM Major: Core Courses : 21 Credits

    E-Print Network [OSTI]

    Srinivasan, N.

    :0 Diffusion in Solids MT 225 3:0 Deformation and Failure Mechanisms at Elevated Temperatures MT 233 3, and nanotechnology. MT 101 3:0 January (4th Semester) Introduction to Materials Science Bonding, types of materials of structural characterization. Thermodynamics of solid solutions, phase diagrams, defects, diffusion

  2. Analytical modeling in support of the development of fiber reinforced ceramic composite materials for re-heater burners

    SciTech Connect (OSTI)

    Kibler, J.J. [Materials Sciences Corp., Fort Washington, PA (United States); DiPietro, S.G. [Textron Specialty Materials, Lowell, MA (United States)

    1995-10-01T23:59:59.000Z

    Development of Continuous Fiber reinforced Ceramic Composite (CFCC) materials is a process of identifying components which will benefit from CFCC properties, and defining appropriate composite constructions which will provide materials which will meet the structural and thermal requirements of the application. Materials Sciences Corporation (MSC) has been providing analytical support to Textron Specialty Materials in the development of re-heated tubes for metal reheating furnaces. As part of this support, a study has been made of the sensitivity of composite properties to fiber orientation as well as a number of matrix properties which control the stress-strain behavior of the composite.

  3. Hydrodynamic effects of eroded materials on response of plasma-facing component during a tokamak disruption

    SciTech Connect (OSTI)

    Hassanein, A.; Konkashbaev, I.

    1999-10-25T23:59:59.000Z

    Loss of plasma confinement causes surface and structural damage to plasma-facing materials (PFMs) and remains a major obstacle for tokamak reactors. The deposited plasma energy results in surface erosion and structural failure. The surface erosion consists of vaporization, spallation, and liquid splatter of metallic materials, while the structural damage includes large temperature increases in structural materials and at the interfaces between surface coatings and structural members. Comprehensive models (contained in the HEIGHTS computer simulation package) are being used self-consistently to evaluate material damage. Splashing mechanisms occur as a result of volume bubble boiling and liquid hydrodynamic instabilities and brittle destruction mechanisms of nonmelting materials. The effect of macroscopic erosion on total mass losses and lifetime is evaluated. The macroscopic erosion products may further protect PFMs from severe erosion (via the droplet-shielding effect) in a manner similar to that of the vapor shielding concept.

  4. Evaluations of Structural Failure Probabilities and Candidate Inservice Inspection Programs

    SciTech Connect (OSTI)

    Khaleel, Mohammad A.; Simonen, Fredric A.

    2009-05-01T23:59:59.000Z

    The work described in this report applies probabilistic structural mechanics models to predict the reliability of nuclear pressure boundary components. These same models are then applied to evaluate the effectiveness of alternative programs for inservice inspection to reduce these failure probabilities. Results of the calculations support the development and implementation of risk-informed inservice inspection of piping and vessels. Studies have specifically addressed the potential benefits of ultrasonic inspections to reduce failure probabilities associated with fatigue crack growth and stress-corrosion cracking. Parametric calculations were performed with the computer code pc-PRAISE to generate an extensive set of plots to cover a wide range of pipe wall thicknesses, cyclic operating stresses, and inspection strategies. The studies have also addressed critical inputs to fracture mechanics calculations such as the parameters that characterize the number and sizes of fabrication flaws in piping welds. Other calculations quantify uncertainties associated with the inputs calculations, the uncertainties in the fracture mechanics models, and the uncertainties in the resulting calculated failure probabilities. A final set of calculations address the effects of flaw sizing errors on the effectiveness of inservice inspection programs.

  5. Materials for defense/aerospace applications (NON-SV)

    SciTech Connect (OSTI)

    Ellis, A. R.

    2012-03-01T23:59:59.000Z

    Through this effort, Sandia and Lockheed Martin Aeronautics Company (LM Aero) sought to assess the feasibility of (1) applying special materials to a defense application; (2) developing a piezoelectric-based micro thermophotovoltaic (TPV) cell; and (3) building and delivering a prototype laboratory emission measurement system. This project supported the Stockpile Research & Development Program by contributing to the development of radio frequency (RF) MEMS- and optical MEMS-based components - such as switches, phase shifters, oscillators, and filters - with improved performance and reduced weight and size. Investigation of failure mechanisms and solutions helped to ensure that MEMS-based technology will meet performance requirements and long term reliability goals in the specified environments dictated by Lockheed Martin's commercial and defense applications. The objectives of this project were to (1) fabricate and test materials for military applications; (2) perform a feasibility study of a piezoelectric-based micro TPV cell; and (3) build and deliver a prototype laboratory emission measurement system. Sandia fabricated and tested properties of materials, studied options for manufacturing scale-up, and delivered a prototype IR Emissometer. LM Aero provided material requirements and designs. Both participated in the investigation of attachment methods and environmental effects on material performance, a feasibility study of piezoelectric TPV cells, an investigation and development of new approaches to implement the required material functionality, and analysis and validation of material performance physics, numerical models, and experimental metrology.

  6. Materials of Gasification

    SciTech Connect (OSTI)

    None

    2005-09-15T23:59:59.000Z

    The objective of this project was to accumulate and establish a database of construction materials, coatings, refractory liners, and transitional materials that are appropriate for the hardware and scale-up facilities for atmospheric biomass and coal gasification processes. Cost, fabricability, survivability, contamination, modes of corrosion, failure modes, operational temperatures, strength, and compatibility are all areas of materials science for which relevant data would be appropriate. The goal will be an established expertise of materials for the fossil energy area within WRI. This would be an effort to narrow down the overwhelming array of materials information sources to the relevant set which provides current and accurate data for materials selection for fossil fuels processing plant. A significant amount of reference material on materials has been located, examined and compiled. The report that describes these resources is well under way. The reference material is in many forms including texts, periodicals, websites, software and expert systems. The most important part of the labor is to refine the vast array of available resources to information appropriate in content, size and reliability for the tasks conducted by WRI and its clients within the energy field. A significant has been made to collate and capture the best and most up to date references. The resources of the University of Wyoming have been used extensively as a local and assessable location of information. As such, the distribution of materials within the UW library has been added as a portion of the growing document. Literature from recent journals has been combed for all pertinent references to high temperature energy based applications. Several software packages have been examined for relevance and usefulness towards applications in coal gasification and coal fired plant. Collation of the many located resources has been ongoing. Some web-based resources have been examined.

  7. Formulations, simulations and evaluations associated with thermo-mechanical models for underground coal gasification

    SciTech Connect (OSTI)

    Advani, S.H.

    1983-01-01T23:59:59.000Z

    Model formulations and governing equations for the investigation of the thermo-mechanical, consolidation and failure responses associated with UCG are given. Typical results from sample finite element model representations are presented. The examples quoted include the simulation of the transient temperature profiles, thermo-elastic stresses incorporating temperature dependent material properties and fracture responses. The application of the developed models to the evaluation of field experiments is demonstrated by the simulation of the Hoe Creek II experiments. The numerical experiments for different overburden failure thresholds demonstrated the pronounced sensitivity of the predicted cavity shapes with respect to the assumed properties.

  8. UQ and V&V techniques applied to experiments and simulations of heated pipes pressurized to failure.

    SciTech Connect (OSTI)

    Romero, Vicente Jose; Dempsey, J. Franklin; Antoun, Bonnie R.

    2014-05-01T23:59:59.000Z

    This report demonstrates versatile and practical model validation and uncertainty quantification techniques applied to the accuracy assessment of a computational model of heated steel pipes pressurized to failure. The Real Space validation methodology segregates aleatory and epistemic uncertainties to form straightforward model validation metrics especially suited for assessing models to be used in the analysis of performance and safety margins. The methodology handles difficulties associated with representing and propagating interval and/or probabilistic uncertainties from multiple correlated and uncorrelated sources in the experiments and simulations including: material variability characterized by non-parametric random functions (discrete temperature dependent stress-strain curves); very limited (sparse) experimental data at the coupon testing level for material characterization and at the pipe-test validation level; boundary condition reconstruction uncertainties from spatially sparse sensor data; normalization of pipe experimental responses for measured input-condition differences among tests and for random and systematic uncertainties in measurement/processing/inference of experimental inputs and outputs; numerical solution uncertainty from model discretization and solver effects.

  9. Nickel alloy stud bolts failure: A case history

    SciTech Connect (OSTI)

    Toffolo, G.; Fassina, P.; Marangoni, M. [AGIP SpA, Milan (Italy); Msallem, A. [AGIP Oil, Tripoli (Libyan Arab Jamahiriya)

    1996-12-01T23:59:59.000Z

    High strength and corrosion resistance material as Inconel X-750 has been selected for the seal flange bolts in an off-shore field in Libya, due to its properties at high temperature, needed for compliance with Fire Safe requirements. After 4 years from the production start-up, during a routine maintenance of wellheads, some bolts have been found cracked. The paper deals with all the activities done in order to understand the cause of the failure. In particular failure analysis has been carried out through laboratory investigation, and shop tests have been conducted to confirm the field procedure and determine the tension on the bolts during the installation. The main conclusion was that the bolts failed due to the concurrence of stress (over-torque that means stress level higher than yield one) and corrosion (pit/crevice conditions). This environmentally assisted failure is known as Hydrogen Embrittlement (HE). Test carried out using the same X-mas tree mounted on the platform justifies the assumption that in the field, where the conditions are far from the ideal, it is possible that even when a uniform torque is set, the tensile stress applied to the bolts is not uniform, making the situation critical. From the corrosion side, the failed bolts showed some corrosion points near the cracks, as due to environment in the crevice/pitting conditions required to justify the hydrogen presence (the bolts are not cathodically protected). Fatigue has been demonstrated not to be responsible for the failure. Solutions are recommended which can safely be adopted during the installation and the substitution of bolts on an existing wellhead, which is operative under pressure without shutting in the well, and not impairing the safety operating envelope.

  10. Fatigue failure in thin-film polysilicon is due to subcriticalcracking within the oxide layer

    SciTech Connect (OSTI)

    Alsem, D.H.; Muhlstein, C.L.; Stach, E.A.; Ritchie, R.O.

    2005-01-11T23:59:59.000Z

    It has been established that microelectromechanical systems (MEMS) created from polycrystalline silicon thin-films are subject to cyclic fatigue. Prior work by the authors has suggested that although bulk silicon is not susceptible to fatigue failure in ambient air, fatigue in micron-scale silicon is a result of a ''reaction-layer'' process, whereby high stresses induce a thickening of the post-release oxide at stress concentrations such as notches, which subsequently undergoes moisture-assisted cracking. However, there exists some controversy regarding the post-release oxide thickness of the samples used in the prior study. In this Letter, we present data from devices from a more recent fabrication run that confirm our prior observations. Additionally, new data from tests in high vacuum show that these devices do not fatigue when oxidation and moisture are suppressed. Each of these observations lends credence to the '''reaction-layer'' mechanism. Recent advances in the design of microelectromechanical systems (MEMS) have increased the demand for more reliable microscale structures. Although silicon is an effective and widely used structural material at the microscale, it is very brittle. Consequently, reliability is a limiting factor for commercial and defense applications. Since the surface to volume ratio of these structural films is very large, classical models for failure modes in bulk materials cannot always be applied. For example, whereas bulk silicon is immune to cyclic fatigue failure thin micron-scale structural films of silicon appear to be highly susceptible. It is clear that at these size scales, surface effects may become dominant in controlling mechanical properties. The main reliability issues for MEMS are stiction, fatigue and wear. Fatigue is important in cases where devices are subjected to a large number of loading cycles with amplitudes below their (single-cycle) fracture stress, which may arise due to vibrations intentionally induced in the structure (i.e. a resonator) or those which arise from the service environment. While the reliability of MEMS has received extensive attention, the physical mechanisms responsible for these failure modes have yet to be conclusively determined. This is particularly true for fatigue, where the mechanisms have been subject to intense debate. Recently we have proposed that the fatigue of micron-scale polysilicon is associated with stress-induced surface oxide thickening and moisture-assisted subcritical cracking in the amorphous SiO{sub 2} oxide layer (''reaction-layer'' fatigue). The mechanism of oxide thickening is as yet unknown, but is likely related to some form of stress-assisted diffusion. Allameh et al. suggest a complementary mechanism involving stress-assisted oxide thickening, caused by dissolution of the surface oxide which forms deep grooves that are sites for crack initiation. Kahn et al. have criticized these mechanisms and proposed that, instead, fatigue is caused by subcritical cracking due to contacting surface asperities in the compressive part of the cycle. To the authors' knowledge, there is no direct experimental observation of such asperity contact. Also, their model cannot explain why micron-scale silicon, and not bulk silicon, is susceptible to fatigue. Moreover, Kahn et al. do not acknowledge the role of stress-induced oxide thickening, which has been observed directly using TEM and indirectly using atomic-force microscope measurements by several investigators, and have questioned whether the materials utilized by Muhlstein et al. and Allameh et al. were representative due to the relatively thick oxide scales. Accordingly, the goal of the present research is to seek a definitive understanding of the physical mechanisms responsible for fatigue in polysilicon structural thin-films. Our approach is to combine on-chip testing methods with electron microscopy by fatiguing thin-film samples and observing them, in an unthinned condition, using high-voltage transmission electron microscopy (HVTEM). Two principal results are found from this work: (1

  11. Reliability in layered networks with random link failures

    E-Print Network [OSTI]

    Lee, Kayi

    We consider network reliability in layered networks where the lower layer experiences random link failures. In layered networks, each failure at the lower layer may lead to multiple failures at the upper layer. We generalize ...

  12. Sandia National Laboratories: Failure Mode and Effect Analysis...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ProcessFailure Mode and Effect Analysis (FMEA) Tutorial Failure Mode and Effect Analysis (FMEA) Tutorial Failure Mode and Effect Analysis (FMEA) Tutorial (SAND2012-0602W) Tagged...

  13. MSE 410: Materials Foundations for Energy Applications MSE 810: Materials for Energy Applications

    E-Print Network [OSTI]

    ; materials for future wind energy needs; thermoelectric materials for solid state energy conversion II: thermoelectric materials Introduction; the design of thermoelectric materials Morelli Jan 31, Feb 2 Module II: thermoelectric materials Thermal and electrical transport properties; model systems

  14. Methodology for developing Version 2.0 of the MECcheck{trademark} materials for the 1992, 1993, and 1995 Model Energy Codes

    SciTech Connect (OSTI)

    Connell, L.M.; Lucas, R.G.; Taylor, Z.T.

    1996-06-01T23:59:59.000Z

    To help builders comply with the Council of American Building Officials (CABO) Model Energy Code (MEC), and to help code officials enforce the MEC requirements, the US Department of Energy (DOE) directed Pacific Northwest National Laboratory (PNNL) to develop the MECcheck{trademark} compliance materials. The materials include a compliance and enforcement manual for all the MEC requirements, prescriptive packages, software, and a trade-off worksheet (included in the compliance manual) to help comply with the thermal envelope requirements. The materials can be used for single-family and low- rise multifamily dwellings. The materials allow building energy efficiency measures (such as insulation levels) to be ``traded off`` against each other, allowing a wide variety of building designs to comply with the MEC. The materials were developed to provide compliance methods that are easy to use and understand. MECcheck compliance materials have been developed for three different editions of the MEC: the 1992, 1993, and 1995 editions. Although some requirements contained in the 1992, 1993, and 1995 MEC changed, the methodology used to develop the MECcheck materials for these three editions is essentially identical. This document explains the methodology used to produce the three MECcheck compliance approaches for meeting the MEC`s thermal envelope requirements--the prescriptive package approach, the software approach, and the trade-off approach. The MECcheck material are largely oriented to assisting the builder in meeting the most complicated part of the MEC--the building envelope U{sub o}-, U-, and R-value requirements in Section 502 of the MEC. This document details the calculations and assumptions underlying the treatment of the MEC requirements in MECcheck, with a major emphasis on the building envelope requirements.

  15. NREL Test-to-Failure Protocol (Presentation)

    SciTech Connect (OSTI)

    Hacke, P.

    2012-03-01T23:59:59.000Z

    The presentation describes the test-to-failure protocol that was developed and piloted at NREL, stressing PV modules with multiple applications of damp heat (with bias) and thermal cycling until they fail.

  16. Autonomous Thruster Failure Recovery for Underactuated Spacecraft

    E-Print Network [OSTI]

    . Miller September 2010 SSL #13­10 #12;2 #12;Autonomous Thruster Failure Recovery for Underactuated Spacecraft Christopher Masaru Pong, David W. Miller September 2010 SSL #12­11 This work is based

  17. Impact of Motor Failures on Payback Periods

    E-Print Network [OSTI]

    Cheek, K. F.; Pillay, P.; Dudley, K. J.

    This paper uses MotorMaster and Vaughen's Complete Price Guide to determine payback periods for different motor failure scenarios. Some scenarios considered are rewinds, reconditions, and replacement of bearings. Prices for these repairs...

  18. Universitat Augsburg Failure-Sensitive Specification

    E-Print Network [OSTI]

    Reif, Wolfgang

    techniques like fault tree analysis (FTA) [14], failure modes and effects analysis (FMEA), or preliminary as well. In this context we already formalized techniques like FTA [12][4] or FMEA. This paper presents

  19. A Study to Verify the Material Surface Concept of Water Table by Examining Analytical and Numerical Models.

    E-Print Network [OSTI]

    Dadi, Sireesh Kumar

    2011-10-21T23:59:59.000Z

    The highly nonlinear nature of unsaturated flow results in different ways to approximate the delayed or instantaneous movement of the water table. In nearly all the approaches, the water table is conceptually treated as a “material surface...

  20. A model for materials scientists: Water runs off the surface of a lotus leaf without a trace. Researchers

    E-Print Network [OSTI]

    to the annoying smears on window panes, it could also make it possible to produce self-cleaning solar panels the annoying smeary film that gets left behind. Reliably self-cleaning MATERIAL & TECHNOLOGY

  1. Electronic Colon Cleansing by Colonic Material Tagging and Image Segmentation for Polyp Detection: Detection Model and Method Evaluation1

    E-Print Network [OSTI]

    suspension (2.1% w/v, E-Z-EM, Inc.) was mixed in each meal. Most colonic materials were moved out, Electrical Engineering and Computer Science, State University of New York Stony Brook, NY 11794, USA Abstract

  2. Integrating Electricity Subsector Failure Scenarios into a Risk...

    Broader source: Energy.gov (indexed) [DOE]

    Integrating Electricity Subsector Failure Scenarios into a Risk Assessment Methodology (December 2013) Integrating Electricity Subsector Failure Scenarios into a Risk Assessment...

  3. U-240: Apple Remote Desktop Encryption Failure Lets Remote Users...

    Broader source: Energy.gov (indexed) [DOE]

    0: Apple Remote Desktop Encryption Failure Lets Remote Users Obtain Potentially Sensitive Information U-240: Apple Remote Desktop Encryption Failure Lets Remote Users Obtain...

  4. Materials Scientist

    Broader source: Energy.gov [DOE]

    Alternate Title(s):Materials Research Engineer; Metallurgical/Chemical Engineer; Product Development Manager;

  5. Ductile failure X-prize.

    SciTech Connect (OSTI)

    Cox, James V.; Wellman, Gerald William; Emery, John M.; Ostien, Jakob T.; Foster, John T.; Cordova, Theresa Elena; Crenshaw, Thomas B.; Mota, Alejandro; Bishop, Joseph E.; Silling, Stewart Andrew; Littlewood, David John; Foulk, James W., III; Dowding, Kevin J.; Dion, Kristin; Boyce, Brad Lee; Robbins, Joshua H.; Spencer, Benjamin Whiting

    2011-09-01T23:59:59.000Z

    Fracture or tearing of ductile metals is a pervasive engineering concern, yet accurate prediction of the critical conditions of fracture remains elusive. Sandia National Laboratories has been developing and implementing several new modeling methodologies to address problems in fracture, including both new physical models and new numerical schemes. The present study provides a double-blind quantitative assessment of several computational capabilities including tearing parameters embedded in a conventional finite element code, localization elements, extended finite elements (XFEM), and peridynamics. For this assessment, each of four teams reported blind predictions for three challenge problems spanning crack initiation and crack propagation. After predictions had been reported, the predictions were compared to experimentally observed behavior. The metal alloys for these three problems were aluminum alloy 2024-T3 and precipitation hardened stainless steel PH13-8Mo H950. The predictive accuracies of the various methods are demonstrated, and the potential sources of error are discussed.

  6. DETERMINATION OF ELECTROCHEMICAL PERFORMANCE, AND THERMO-MECHANICALCHEMICAL STABILITY OF SOFCS FROM DEFECT MODELING

    SciTech Connect (OSTI)

    Wachsman, E.D.; Duncan, K.L.; Ebrahimi, F.

    2005-01-27T23:59:59.000Z

    The objectives of this project were to: provide fundamental relationships between SOFC performance and operating conditions and transient (time dependent) transport properties; extend models to thermo-mechanical stability, thermo-chemical stability, and multilayer structures; incorporate microstructural effects such as grain boundaries and grain-size distribution; experimentally verify models and devise strategies to obtain relevant material constants; and assemble software package for integration into SECA failure analysis models.

  7. A new method for modelling roofing materials emissions on the city scale: Application for zinc in the city of Crteil

    E-Print Network [OSTI]

    Boyer, Edmond

    as an important source of environmental pollution. Roofing materials, in particular the metallic ones, are considered as a major source of urban runoff metal contaminations. In the context of the European Water Directive (2000/60 CE), an accurate evaluation of contaminant flows from roofs is thus required on the city

  8. Development of Novel Polymeric Materials for Gene Therapy and pH-Sensitive Drug Delivery: Modeling, Synthesis, Characterization, and Analysis

    SciTech Connect (OSTI)

    Brian Curtis Anderson

    2002-08-27T23:59:59.000Z

    The underlying theme of this thesis is the use of polymeric materials in bioapplications. Chapters 2-5 either develop a fundamental understanding of current materials used for bioapplications or establish protocols and procedures used in characterizing and synthesizing novel materials. In chapters 6 and 7 these principles and procedures are applied to the development of materials to be used for gene therapy and drug delivery. Chapter one is an introduction to the ideas that will be necessary to understand the subsequent chapters, as well as a literature review of these topics. Chapter two is a paper that has been published in the ''Journal of Controlled Release'' that examines the mechanism of drug release from a polymer gel, as well as experimental design suggestions for the evaluation of water soluble drug delivery systems. Chapter three is a paper that has been published in the ''Journal of Pharmaceutical Sciences'' that discusses the effect ionic salts have on properties of the polymer systems examined in chapter two. Chapter four is a paper published in the Materials Research Society Fall 2000 Symposium Series dealing with the design and synthesis of a pH-sensitive polymeric drug delivery device. Chapter five is a paper that has been published in the journal ''Biomaterials'' proposing a novel polymer/metal composite for use as a biomaterial in hip arthroplasty surgery. Chapter six is a paper that will appear in an upcoming volume of the Journal ''Biomaterials'' dealing with the synthesis of a novel water soluble cationic polymer with possible applications in non-viral gene therapy. Chapter seven is a paper that has been submitted to ''Macromolecules'' discussing several novel block copolymers based on poly(ethylene glycol) and poly(diethylamino ethyl methacrylate) that possess both pH-sensitive and temperature sensitive properties. Chapter eight contains a summary of the research contained in chapters 2-7 and proposes future research for the gene therapy and drug delivery projects.

  9. Absolute nuclear material assay

    DOE Patents [OSTI]

    Prasad, Manoj K. (Pleasanton, CA); Snyderman, Neal J. (Berkeley, CA); Rowland, Mark S. (Alamo, CA)

    2012-05-15T23:59:59.000Z

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  10. Insulation failure assessment under random energization overvoltages

    SciTech Connect (OSTI)

    Mahdy, A.M.; Anis, H.I. [Cairo Univ. (Egypt)] [Cairo Univ. (Egypt); El-Morshedy, A. [Faculty of Science for Girls, Dammam (Saudi Arabia)] [Faculty of Science for Girls, Dammam (Saudi Arabia)

    1996-03-01T23:59:59.000Z

    This paper offers a new simple approach to the evaluation of the risk of failure of external insulation in view of their known probabilistic nature. This is applied to EHV transmission systems subjected to energization overvoltages. The randomness, both in the applied stresses and insulation`s withstand characteristics are numerically simulated and then integrated to assess the risk of failure. Overvoltage control methods are accounted for, such as the use of pre-insertion breaker resistors, series capacitive compensation, and the installation of shunt reactors.

  11. Finite Element Studies in the Out-Of-Plane Failure of Unreinfored Masonry

    E-Print Network [OSTI]

    Martini, Kirk

    , modelling phenomena resulting from different elastic properties of block and mortar. · Joints and associated local effects at the block-mortar interface, instead model- ling the mortar joints as potential lines of failure due to cracking. · Joints are smeared out. In this approach, the block-mortar composite

  12. weapons material

    National Nuclear Security Administration (NNSA)

    2%2A en Office of Weapons Material Protection http:nnsa.energy.govaboutusourprogramsnonproliferationprogramofficesinternationalmaterialprotectionandcooperation-1

  13. Microstructure and Property Evolution in Advanced Cladding and Duct Materials Under Long-Term and Elevated Temperature Irradiation: Modeling and Experimental Investigation

    SciTech Connect (OSTI)

    Wirth, Brian; Morgan, Dane; Kaoumi, Djamel; Motta, Arthur

    2013-12-01T23:59:59.000Z

    The in-service degradation of reactor core materials is related to underlying changes in the irradiated microstructure. During reactor operation, structural components and cladding experience displacement of atoms by collisions with neutrons at temperatures at which the radiation-induced defects are mobile, leading to microstructure evolution under irradiation that can degrade material properties. At the doses and temperatures relevant to fast reactor operation, the microstructure evolves by dislocation loop formation and growth, microchemistry changes due to radiation-induced segregation, radiation-induced precipitation, destabilization of the existing precipitate structure, and in some cases, void formation and growth. These processes do not occur independently; rather, their evolution is highly interlinked. Radiationinduced segregation of Cr and existing chromium carbide coverage in irradiated alloy T91 track each other closely. The radiation-induced precipitation of Ni-Si precipitates and RIS of Ni and Si in alloys T91 and HCM12A are likely related. Neither the evolution of these processes nor their coupling is understood under the conditions required for materials performance in fast reactors (temperature range 300-600°C and doses beyond 200 dpa). Further, predictive modeling is not yet possible as models for microstructure evolution must be developed along with experiments to characterize these key processes and provide tools for extrapolation. To extend the range of operation of nuclear fuel cladding and structural materials in advanced nuclear energy and transmutation systems to that required for the fast reactor, the irradiation-induced evolution of the microstructure, microchemistry, and the associated mechanical properties at relevant temperatures and doses must be understood. Predictive modeling relies on an understanding of the physical processes and also on the development of microstructure and microchemical models to describe their evolution under irradiation. This project will focus on modeling microstructural and microchemical evolution of irradiated alloys by performing detailed modeling of such microstructure evolution processes coupled with well-designed in situ experiments that can provide validation and benchmarking to the computer codes. The broad scientific and technical objectives of this proposal are to evaluate the microstructure and microchemical evolution in advanced ferritic/martensitic and oxide dispersion strengthened (ODS) alloys for cladding and duct reactor materials under long-term and elevated temperature irradiation, leading to improved ability to model structural materials performance and lifetime. Specifically, we propose four research thrusts, namely Thrust 1: Identify the formation mechanism and evolution for dislocation loops with Burgers vector of a<100> and determine whether the defect microstructure (predominately dislocation loop/dislocation density) saturates at high dose. Thrust 2: Identify whether a threshold irradiation temperature or dose exists for the nucleation of growing voids that mark the beginning of irradiation-induced swelling, and begin to probe the limits of thermal stability of the tempered Martensitic structure under irradiation. Thrust 3: Evaluate the stability of nanometer sized Y- Ti-O based oxide dispersion strengthened (ODS) particles at high fluence/temperature. Thrust 4: Evaluate the extent to which precipitates form and/or dissolve as a function of irradiation temperature and dose, and how these changes are driven by radiation induced segregation and microchemical evolutions and determined by the initial microstructure.

  14. Effects of pacing site on global and regional left ventricular function in the setting of dyssynchronous heart failure

    E-Print Network [OSTI]

    Howard, Elliot Jacob

    2011-01-01T23:59:59.000Z

    modeling of dyssynchronous heart failure: A case study.in the dyssynchronous canine heart. Annual Meeting of therelaxation. Am J Physiol Heart Circ Physiol 286: H640-647,

  15. Human Factors Process Failure Mode and Effects Analysis (HF PFMEA) Application in the Evaluation of Management Risks

    E-Print Network [OSTI]

    Soguilon, Nenita M.

    2009-12-18T23:59:59.000Z

    .3.1. Mechanisms of Prevention ............................................................................................... 11 2.4. Human Factors Process Failure Mode and Effects Analysis (HF PFMEA) ....................... 11 2.5. FMEA Components... ........................................................................................... 15 2.5.5. Risk Priority Number ....................................................................................................... 17 2.6. FMEA Model...

  16. Battelle determines cause of Ashland tank failure

    SciTech Connect (OSTI)

    Mesloh, R.E.; Marschall, C.W.; Buchheit, R.D.; Kiefner, J.F. (Battelle Memorial Institute, Columbus, OH (US))

    1988-09-26T23:59:59.000Z

    An existing flaw, combined with embrittled steel and residual stresses, led to the catastrophic failure of the fuel oil tank at Ashland Petroleum Co., Floreffe, Pa., last January. Here is a look at the tank's background, events surrounding its rupture, and Battelle's methods for investigating the incident.

  17. Field Failure Prediction Using Dynamic Environmental Data

    E-Print Network [OSTI]

    to varying failure-causing stresses. Some prod- ucts are equipped with sensors and smart chips that measure- ate time series; reliability; usage history. 1 Introduction 1.1 Background Laboratory tests from sensors and #12;2 Yili Hong and William Q. Meeker smart chips that are installed in a product

  18. Commutation failures in HVDC transmission systems

    SciTech Connect (OSTI)

    Thio, C.V.; Davies, J.B.; Kent, K.L. [Manitoba Hydro, Winnipeg, Manitoba (Canada)] [Manitoba Hydro, Winnipeg, Manitoba (Canada)

    1996-04-01T23:59:59.000Z

    This paper provides a formulation for the initiation or onset mechanism of commutation failures in line-commutated thyristor converters, assuming infinite (zero impedance) ac systems. A theoretical development and a parametric analysis is given. Theory validation by simulation and comparison to actual field experience data is also given.

  19. INSTITUTE OF PHYSICS PUBLISHING MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING Modelling Simul. Mater. Sci. Eng. 12 (2004) 929943 PII: S0965-0393(04)80701-0

    E-Print Network [OSTI]

    Anderson, Peter M.

    Modelling Simul. Mater. Sci. Eng. 12 (2004) 929­943 PII: S0965-0393(04)80701-0 A three-dimensional cellular

  20. INSTITUTE OF PHYSICS PUBLISHING MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING Modelling Simul. Mater. Sci. Eng. 12 (2004) 197204 PII: S0965-0393(04)70548-3

    E-Print Network [OSTI]

    Deymier, Pierre

    Modelling Simul. Mater. Sci. Eng. 12 (2004) 197­204 PII: S0965-0393(04)70548-3 Formation of bound states

  1. Evaluation of Corrosion Failure in Tractor-Trailer Brake System

    SciTech Connect (OSTI)

    Wilson, DF

    2002-10-22T23:59:59.000Z

    As reported to ORNL, concomitant with the introduction of different deicing and anti-icing compounds, there was an increase in the brake failure rate of tractor-trailer trucks. A forensic evaluation of a failed brake system was performed. Optical and scanning electron microscopic evaluation showed corrosion to be mostly confined to the brake table/lining interface. The corrosion is non-uniform as is to be expected for plain carbon steel in chloride environments. This initial analysis found no evidence for the chlorides of calcium and magnesium, which are the newly introduced deicing and antiicing compounds and are less soluble in water than the identified chlorides of sodium and potassium, in the scale. The result could be as a result of non-exposure of the examined brake table to calcium and magnesium chloride. The mechanisms for the increased failure rate are postulated as being an increased rate of corrosion due to positive shifts in the corrosion potential, and an increased amount of corrosion due to an increased ''time of wetness'' that results from the presence of hygroscopic salts. Laboratory scale evaluation of the corrosion of plain carbon steel in simulated deicing and anti-icing solutions need to be performed to determine corrosion rates and morphological development of corrosion product, to compare laboratory data to in-service data, and to rank economically feasible replacement materials for low carbon steel. In addition, the mechanical behavior of the lining attached to the brake shoe table needs to be assessed. It is opined that an appropriate adjustment of materials could easily allow for a doubling of a brake table/lining lifetime. Suggestions for additional work, to clarify the mechanisms of rust jacking and to develop possible solutions, are described.

  2. Scintillator material

    DOE Patents [OSTI]

    Anderson, D.F.; Kross, B.J.

    1992-07-28T23:59:59.000Z

    An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography. 4 figs.

  3. Scintillator material

    DOE Patents [OSTI]

    Anderson, D.F.; Kross, B.J.

    1994-06-07T23:59:59.000Z

    An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography. 4 figs.

  4. Scintillator material

    DOE Patents [OSTI]

    Anderson, David F. (Batavia, IL); Kross, Brian J. (Aurora, IL)

    1992-01-01T23:59:59.000Z

    An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography.

  5. Scintillator material

    DOE Patents [OSTI]

    Anderson, David F. (Batavia, IL); Kross, Brian J. (Aurora, IL)

    1994-01-01T23:59:59.000Z

    An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography.

  6. Diffusion and Rheology in a Model of Glassy Materials R. M. L. Evans, M. E. Cates & P. Sollich \\Lambda

    E-Print Network [OSTI]

    Sollich, Peter

    (foams, emulsions etc.) as well as to conventional glass­forming liquids is discussed. I. INTRODUCTION is Bouchaud's model of glasses [J.­P. Bouchaud, J. Physique I 2 1705 (1992)], as extended to describe)].) We investigate the breakdown, near the glass transition, of the (generalized) Stokes­ Einstein

  7. Critical Materials:

    Broader source: Energy.gov (indexed) [DOE]

    lighting. 14 (bottom) Criticality ratings of shortlisted raw 76 materials. 15 77 2. Technology Assessment and Potential 78 This section reviews the major trends within...

  8. SMERDON ET AL.: AUXILIARY MATERIAL Auxiliary Material

    E-Print Network [OSTI]

    Smerdon, Jason E.

    run [Ammann et al., 2007; hereinafter CCSM] and the GKSS ECHO-g ERIK2 run [González-Rouco et al., 2006; hereinafter ECHO-g]. The annual means of the modeled temperature fields are interpolated to 5° latitude;SMERDON ET AL.: AUXILIARY MATERIAL 2 ECHO-g simulations, respectively. The above conventions

  9. genBRDF: Synthesizing Novel Analytic BRDFs with Genetic Programming Figure 1: Comparison of BRDFs modeling the tungsten carbide material from the MERL BRDF database. Each scene consists of a sphere

    E-Print Network [OSTI]

    Weimer, Westley

    of BRDFs modeling the tungsten carbide material from the MERL BRDF database. Each scene consists that remains between state-of-the-art analytic BRDFs and measured data in the case of tungsten carbide

  10. Survey of four damage models for concrete.

    SciTech Connect (OSTI)

    Leelavanichkul, Seubpong (University of Utah, Salt Lake City, UT); Brannon, Rebecca Moss (University of Utah, Salt Lake City, UT)

    2009-08-01T23:59:59.000Z

    Four conventional damage plasticity models for concrete, the Karagozian and Case model (K&C), the Riedel-Hiermaier-Thoma model (RHT), the Brannon-Fossum model (BF1), and the Continuous Surface Cap Model (CSCM) are compared. The K&C and RHT models have been used in commercial finite element programs many years, whereas the BF1 and CSCM models are relatively new. All four models are essentially isotropic plasticity models for which 'plasticity' is regarded as any form of inelasticity. All of the models support nonlinear elasticity, but with different formulations. All four models employ three shear strength surfaces. The 'yield surface' bounds an evolving set of elastically obtainable stress states. The 'limit surface' bounds stress states that can be reached by any means (elastic or plastic). To model softening, it is recognized that some stress states might be reached once, but, because of irreversible damage, might not be achievable again. In other words, softening is the process of collapse of the limit surface, ultimately down to a final 'residual surface' for fully failed material. The four models being compared differ in their softening evolution equations, as well as in their equations used to degrade the elastic stiffness. For all four models, the strength surfaces are cast in stress space. For all four models, it is recognized that scale effects are important for softening, but the models differ significantly in their approaches. The K&C documentation, for example, mentions that a particular material parameter affecting the damage evolution rate must be set by the user according to the mesh size to preserve energy to failure. Similarly, the BF1 model presumes that all material parameters are set to values appropriate to the scale of the element, and automated assignment of scale-appropriate values is available only through an enhanced implementation of BF1 (called BFS) that regards scale effects to be coupled to statistical variability of material properties. The RHT model appears to similarly support optional uncertainty and automated settings for scale-dependent material parameters. The K&C, RHT, and CSCM models support rate dependence by allowing the strength to be a function of strain rate, whereas the BF1 model uses Duvaut-Lion viscoplasticity theory to give a smoother prediction of transient effects. During softening, all four models require a certain amount of strain to develop before allowing significant damage accumulation. For the K&C, RHT, and CSCM models, the strain-to-failure is tied to fracture energy release, whereas a similar effect is achieved indirectly in the BF1 model by a time-based criterion that is tied to crack propagation speed.

  11. Material-based design computation

    E-Print Network [OSTI]

    Oxman, Neri

    2010-01-01T23:59:59.000Z

    The institutionalized separation between form, structure and material, deeply embedded in modernist design theory, paralleled by a methodological partitioning between modeling, analysis and fabrication, resulted in ...

  12. Soft torque rotary system reduces drillstring failures

    SciTech Connect (OSTI)

    Javanmardi, K.; Gaspard, D. (Shell Offshore Inc., New Orleans, LA (United States))

    1992-10-12T23:59:59.000Z

    This paper reports that the use of the soft torque system has significantly reduced torque fluctuations (up to 80%), torsional drillstring vibrations, and bit slip-stick conditions to help reduce drillstring failures and improve penetration rates in deep directional wells. The system was instrumental in eliminating expensive ($5-10 million) drillstring failures on Well SL 531 No. 3, a complex directional well in Mobile Bay. The soft torque rotary system attenuates and interrupts the torsional oscillations of the drillstring and thus prevents the buildup of energy in torsional waves that are reflected back and forth between the bit and the rotary table. The soft torque rotary system can be installed on any rig equipped with an independent electronically driven rotary table or top drive. The system is relatively inexpensive and easy to install.

  13. Failure Detection with Booting in Partially Synchronous Systems

    E-Print Network [OSTI]

    Failure Detection with Booting in Partially Synchronous Systems Josef Widder1 , G´erard Le Lann2 implementation with respect to failure detection time, but also works during the system booting phase. 1

  14. Gearbox Typical Failure Modes, Detection, and Mitigation Methods (Presentation)

    SciTech Connect (OSTI)

    Sheng, S.

    2014-01-01T23:59:59.000Z

    This presentation was given at the AWEA Operations & Maintenance and Safety Seminar and focused on what the typical gearbox failure modes are, how to detect them using detection techniques, and strategies that help mitigate these failures.

  15. Reduce Steam Trap Failures at Chambers Works

    E-Print Network [OSTI]

    Kouba, C.

    Ultrasonic Inspection At least 2 times per year Steam Trap Surveyor Submit reports to area management, energy team, and reliability engineers for each area every month Steam Trap Team Leader Control Plan ? Process Owner agrees...Reduce Steam Trap Failures at Chambers Works GB/BB Name: Cyndi Kouba Mentor/MBB: Andrew Degraff Team Members Michael Crowley(Site Energy Lead), (Charlie) Flanigan (Aramids-maintenance), Ben Snyder (Aramids-ATO), Michael Scruggs (Central...

  16. Timing analysis of PWR fuel pin failures

    SciTech Connect (OSTI)

    Jones, K.R.; Wade, N.L.; Katsma, K.R.; Siefken, L.J. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Straka, M. (Halliburton NUS, Idaho Falls, ID (United States))

    1992-09-01T23:59:59.000Z

    This report discusses research conducted to develop and demonstrate a methodology for calculation of the time interval between receipt of the containment isolation signals and the first fuel pin failure for loss-of-coolant accidents (LOCAs). Demonstration calculations were performed for a Babcock and Wilcox (B W) design (Oconee) and a Westinghouse (W) four-loop design (Seabrook). Sensitivity studies were performed to assess the impacts of fuel pin burnup, axial peaking factor, break size, emergency core cooling system availability, and main coolant pump trip on these times. The analysis was performed using the following codes: FRAPCON-2, for the calculation of steady-state fuel behavior; SCDAP/RELAP5/MOD3 and TRACPF1/MOD1, for the calculation of the transient thermal-hydraulic conditions in the reactor system; and FRAP-T6, for the calculation of transient fuel behavior. In addition to the calculation of fuel pin failure timing, this analysis provides a comparison of the predicted results of SCDAP/RELAP5/MOD3 and TRAC-PF1/MOD1 for large-break LOCA analysis. Using SCDAP/RELAP5/MOD3 thermal-hydraulic data, the shortest time intervals calculated between initiation of containment isolation and fuel pin failure are 10.4 seconds and 19.1 seconds for the B W and W plants, respectively. Using data generated by TRAC-PF1/MOD1, the shortest intervals are 10.3 seconds and 29.1 seconds for the B W and W plants, respectively. These intervals are for a double-ended, offset-shear, cold leg break, using the technical specification maximum peaking factor and applied to fuel with maximum design burnup. Using peaking factors commensurate with actual burnups would result in longer intervals for both reactor designs. This document provides appendices K and L of this report which provide plots for the timing analysis of PWR fuel pin failures for Oconee and Seabrook respectively.

  17. Cermet materials

    DOE Patents [OSTI]

    Kong, Peter C. (Idaho Falls, ID)

    2008-12-23T23:59:59.000Z

    A self-cleaning porous cermet material, filter and system utilizing the same may be used in filtering particulate and gaseous pollutants from internal combustion engines having intermetallic and ceramic phases. The porous cermet filter may be made from a transition metal aluminide phase and an alumina phase. Filler materials may be added to increase the porosity or tailor the catalytic properties of the cermet material. Additionally, the cermet material may be reinforced with fibers or screens. The porous filter may also be electrically conductive so that a current may be passed therethrough to heat the filter during use. Further, a heating element may be incorporated into the porous cermet filter during manufacture. This heating element can be coated with a ceramic material to electrically insulate the heating element. An external heating element may also be provided to heat the cermet filter during use.

  18. Jatropha – An Update Part 5: A systemic knowledge failure

    E-Print Network [OSTI]

    Peter Baker; Zoheir Ebrahim

    approached and dealt with jatropha. The root of the problem, we believe, is the failure to take account of

  19. Synthesis of oligomeric models of coal-derived materials for use with GPC calibration. Quarterly report, June-August 1982. [Gel permeation chromatography

    SciTech Connect (OSTI)

    Baltisberger, R J; Jones, M B

    1982-09-01T23:59:59.000Z

    One important facet of the characterization of coal-derived materials is that of molecular weight determination. Number average molecular weight is usually obtained by vapor pressure osmometry measurements. However, no satisfactory method is available for determining weight average molecular weights. The latter values are useful in predicting rheological properties. Gel permeation chromatography (GPC) is a technique which should be most readily adaptable for this measurement. The other techniques of ultracentrifugation and light scattering are not as readily available as GPC. At this time, satisfactory GPC calibration standards which possess chemical structures similar to coal derived mterials are non-existent. The purpose of this study is to develop a useful set of GPC calibration standards for asphaltene and preaspaltene analyses. Our previous results suggest models in which coal derived preasphaltenes and asphaltenes are composed of oligomeric aromatic ethers of both diaryl and furan types. We plan to synthesize a series of model oligomers that are in agreement with the average structural formulas of some selected coal preasphaltenes as determined by pmr, elemental analyses and various oxygen derivatization procedures. These model compounds will be tested for use as calibration standards for both high pressure gel permeation chromatographic and vapor pressure osmometric procedures. Their response and retention times will be compared with coal preasphaltenes to determine the suitability of the model compounds as calibration standards.

  20. PDC IC WELD FAILURE EVALUATION AND RESOLUTION

    SciTech Connect (OSTI)

    Korinko, P.; Howard, S.; Maxwell, D.; Fiscus, J.

    2012-04-16T23:59:59.000Z

    During final preparations for start of the PDCF Inner Can (IC) qualification effort, welding was performed on an automated weld system known as the PICN. During the initial weld, using a pedigree canister and plug, a weld defect was observed. The defect resulted in a hole in the sidewall of the canister, and it was observed that the plug sidewall had not been consumed. This was a new type of failure not seen during development and production of legacy Bagless Transfer Cans (FB-Line/Hanford). Therefore, a team was assembled to determine the root cause and to determine if the process could be improved. After several brain storming sessions (MS and T, R and D Engineering, PDC Project), an evaluation matrix was established to direct this effort. The matrix identified numerous activities that could be taken and then prioritized those activities. This effort was limited by both time and resources (the number of canisters and plugs available for testing was limited). A discovery process was initiated to evaluate the Vendor's IC fabrication process relative to legacy processes. There were no significant findings, however, some information regarding forging/anneal processes could not be obtained. Evaluations were conducted to compare mechanical properties of the PDC canisters relative to the legacy canisters. Some differences were identified, but mechanical properties were determined to be consistent with legacy materials. A number of process changes were also evaluated. A heat treatment procedure was established that could reduce the magnetic characteristics to levels similar to the legacy materials. An in-situ arc annealing process was developed that resulted in improved weld characteristics for test articles. Also several tack welds configurations were addressed, it was found that increasing the number of tack welds (and changing the sequence) resulted in decreased can to plug gaps and a more stable weld for test articles. Incorporating all of the process improvements for the actual can welding process, however, did not result in an improved weld geometry. Several possibilities for the lack of positive response exist, some of which are that (1) an insufficient number of test articles were welded under prototypic conditions, (2) the process was not optimized so that significant improvements were observable over the 'noise', and (3) the in-situ arc anneal closed the gap down too much so the can was unable to exhaust pressure ahead of the weld. Several operational and mechanical improvements were identified. The weld clamps were changed to a design consistent with those used in the legacy operations. A helium puff operation was eliminated; it is believed that this operation was the cause of the original weld defect. Also, timing of plug mast movement was found to correspond with weld irregularities. The timing of the movement was changed to occur during weld head travel between tacks. In the end a three sequential tack weld process followed by a pulse weld at the same current and travel speed as was used for the legacy processes was suggested for use during the IC qualification effort. Relative to legacy welds, the PDC IC weld demonstrates greater fluctuation in the region of the weld located between tack welds. However, canister weld response (canister to canister) is consistent and with the aid of the optical mapping system (for targeting the cut position) is considered adequate. DR measurements and METs show the PDC IC welds to have sufficient ligament length to ensure adequate canister pressure/impact capacity and to ensure adequate stub function. The PDC welding process has not been optimized as a result of this effort. Differences remain between the legacy BTC welds and the PDC IC weld, but these differences are not sufficient to prevent resumption of the current PDC IC qualification effort. During the PDC IC qualification effort, a total of 17 cans will be welded and a variety of tests/inspections will be performed. The extensive data collected during that qualification effort should be of a sufficient population to determ

  1. Role of seepage forces on hydraulic fracturing and failure patterns

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Role of seepage forces on hydraulic fracturing and failure patterns Alexander Rozhko Thesis September 2007 #12;ii Role of seepage forces on hydraulic fracturing and failure patterns Abstract. The mechanical role of seepage forces on hydraulic fracturing and failure patterns was studied both

  2. Production-Run Software Failure Diagnosis via Hardware Performance Counters

    E-Print Network [OSTI]

    Sheridan, Jennifer

    Production-Run Software Failure Diagnosis via Hardware Performance Counters Joy Arulraj Po and huge financial loss during production runs. Tools that diagnose production-run failures with low is sometimes over 100%, for concurrency-bug failure diagnosis and hence are not suitable for production

  3. Soft Failures in Large Datacenters Sriram Sankar and Sudhanva Gurumurthi

    E-Print Network [OSTI]

    Gurumurthi, Sudhanva

    Soft Failures in Large Datacenters Sriram Sankar and Sudhanva Gurumurthi Abstract-- A major problem in managing large-scale datacenters is diagnosing and fixing machine failures. Most large datacenter an important issue at large datacenters with minimum human intervention. Soft failures in the datacenter do

  4. LESSONS LEARNED FROM A LANDFILL SLOPE FAILURE INVOLVING

    E-Print Network [OSTI]

    LESSONS LEARNED FROM A LANDFILL SLOPE FAILURE INVOLVING GEOSYTNTHETICS Virginia L. Wilson: Geosynthetics: Lessons Learned from Failures International Geosynthetics Society editors J.P. Giroud, K.L. Soderman and G.P. Raymond November 12, 1998 #12;LESSONS LEARNED FROM A LANDFILL SLOPE FAILURE INVOLVING

  5. Title: Some notes on software failure Date: 24/Oct/2001

    E-Print Network [OSTI]

    Hatton, Les

    mathematical technique used for oil & gas exploration is fundamentally damaged by software failure, (Hatton with a state of the art process, the product will exhibit around 1000 defects in its life-cycle of which 50 failure manifests itself in at least three important ways:- ·Process failure. Here the process

  6. NO. ~EV. NO. Failure Modes and Effects Analysis -LRRR

    E-Print Network [OSTI]

    Rathbun, Julie A.

    of the Failure Modes and Effects Analysis (FMEA) is to discover critical failure areas in the LRRR experiment for the critical failure areas. A TM 868 contains the results of a final FMEA for the LRRR experiment. 2. 0 SUMMARY Since an LRRR was successfully deployed on the moon as a part of the Apollo 11 mission, this FMEA

  7. Failure Modes and Effects Analysis 300 Array -LRRR

    E-Print Network [OSTI]

    Rathbun, Julie A.

    of the Failure Modes and Effects Analysis (FMEA) is to discover critical failure areas in a system and to remove failure areas. 1. 2 This memo contains the results of the final FMEA for the 300 Array LRRR experiment was successfully deployed on the moon as a part of the Apollo 11 mission, this FMEA will not dwell in the aspects

  8. Materials for solid state lighting

    SciTech Connect (OSTI)

    Johnson, S.G.; Simmons, J.A.

    2002-03-26T23:59:59.000Z

    Dramatic improvement in the efficiency of inorganic and organic light emitting diodes (LEDs and OLEDs) within the last decade has made these devices viable future energy efficient replacements for current light sources. However, both technologies must overcome major technical barriers, requiring significant advances in material science, before this goal can be achieved. Attention will be given to each technology associated with the following major areas of material research: (1) material synthesis, (2) process development, (3) device and defect physics, and (4) packaging. The discussion on material synthesis will emphasize the need for further development of component materials, including substrates and electrodes, necessary for improving device performance. The process technology associated with the LEDs and OLEDs is very different, but in both cases it is one factor limiting device performance. Improvements in process control and methodology are expected to lead to additional benefits of higher yield, greater reliability and lower costs. Since reliability and performance are critical to these devices, an understanding of the basic physics of the devices and device failure mechanisms is necessary to effectively improve the product. The discussion will highlight some of the more basic material science problems remaining to be solved. In addition, consideration will be given to packaging technology and the need for the development of novel materials and geometries to increase the efficiencies and reliability of the devices. The discussion will emphasize the performance criteria necessary to meet lighting applications, in order to illustrate the gap between current status and market expectations for future product.

  9. An Automated Failure Modes and Effect Analysis Based Visual Matrix Approach to Sensor Selection and

    E-Print Network [OSTI]

    Snooke, Neal

    - prehensive automated Failure Modes and Effects Analysis (FMEA) using qualitative model based reasoning techniques. The automated FMEA pro- vides a comprehensive set of fault­effect rela- tions by qualitative FMEA results in a fault-effect mapping that can be used to investi- gate the diagnosability

  10. Probabilistic Failure Analysis for Wound Composite Ceramic Cladding Assembly

    SciTech Connect (OSTI)

    Hemrick, James Gordon [ORNL] [ORNL; Lara-Curzio, Edgar [ORNL] [ORNL

    2013-01-01T23:59:59.000Z

    Advanced ceramic matrix composites based on silicon carbide (SiC) are being considered as candidate material systems for nuclear fuel cladding in light water reactors. The SiC composite structure is considered due to its assumed exceptional performance under accident scenarios, where its excellent high-temperature strength and slow reaction kinetics with steam and associated mitigated hydrogen production are desirable. The specific structures of interest consist of a monolithic SiC cylinder surrounded by interphase-coated SiC woven fibers in a tubular form and infiltrated with SiC. Additional SiC coatings on the outermost surface of the assembly are also being considered to prevent hydrothermal corrosion of the fibrous structure. The inner monolithic cylinder is expected to provide a hermetic seal to contain fission products under normal conditions. While this approach offers the promise of higher burn-up rates and safer behavior in the case of LOCA events, the reliability of such structures must be demonstrated in advance. Therefore, a probability failure analysis study was performed of such monolithic-composite hybrid structures to determine the feasibility of these design concepts. This analysis will be used to predict the future performance of candidate systems in an effort to determine the feasibility of these design concepts and to make future recommendations regarding materials selection.

  11. NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71-10 / p. 1 of 115 FAILURE MODES AND EFFECTS ANALYSIS

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71-10 / p. 1 of 115 NSTX FAILURE MODES AND EFFECTS ANALYSIS (FMEA) Revision 10 Dated: November 2014 Prepared By: Name/WBS Signature Name: ________________________________________________ Ron Strykowsky, NSTX Upgrade Project Manager #12;NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71

  12. Complex Materials

    ScienceCinema (OSTI)

    Cooper, Valentino

    2014-05-23T23:59:59.000Z

    Valentino Cooper uses some of the world's most powerful computing to understand how materials work at subatomic levels, studying breakthroughs such as piezoelectrics, which convert mechanical stress to electrical energy.

  13. Complex Materials

    SciTech Connect (OSTI)

    Cooper, Valentino

    2014-04-17T23:59:59.000Z

    Valentino Cooper uses some of the world's most powerful computing to understand how materials work at subatomic levels, studying breakthroughs such as piezoelectrics, which convert mechanical stress to electrical energy.

  14. Material Symbols 

    E-Print Network [OSTI]

    Clark, Andy

    2006-01-01T23:59:59.000Z

    What is the relation between the material, conventional symbol structures that we encounter in the spoken and written word, and human thought? A common assumption, that structures a wide variety of otherwise competing ...

  15. Materializing Energy

    E-Print Network [OSTI]

    James Pierce; Eric Paulos

    Motivated and informed by perspectives on sustainability and design, this paper draws on a diverse body of scholarly works related to energy and materiality to articulate a perspective on energy-as-materiality and propose a design approach of materializing energy. Three critical themes are presented: the intangibility of energy, the undifferentiatedness of energy, and the availability of energy. Each theme is developed through combination of critical investigation and design exploration, including the development and deployment of several novel design artifacts: Energy Mementos and The Local Energy Lamp. A framework for interacting with energy-as-materiality is proposed involving collecting, keeping, sharing, and activating energy. A number of additional concepts are also introduced, such as energy attachment, energy engagement, energy attunement, local energy and energy meta-data. Our work contributes both a broader, more integrative design perspective on energy and materiality as well as a diversity of more specific concepts and artifacts that may be of service to designers and researchers of interactive systems concerned with sustainability and energy. Author Keywords Sustainability, energy, materiality, design, design theory

  16. Nuclear Materials

    E-Print Network [OSTI]

    Gihan T. Sayah; Mohamed Abouelatta; Abdelhalim Zekry

    using some analytical expressions. Then, the SPICE model parameters are extracted using Silvaco. The

  17. MULTISCALE PHENOMENA IN MATERIALS

    SciTech Connect (OSTI)

    A. BISHOP

    2000-09-01T23:59:59.000Z

    This project developed and supported a technology base in nonequilibrium phenomena underpinning fundamental issues in condensed matter and materials science, and applied this technology to selected problems. In this way the increasingly sophisticated synthesis and characterization available for classes of complex electronic and structural materials provided a testbed for nonlinear science, while nonlinear and nonequilibrium techniques helped advance our understanding of the scientific principles underlying the control of material microstructure, their evolution, fundamental to macroscopic functionalities. The project focused on overlapping areas of emerging thrusts and programs in the Los Alamos materials community for which nonlinear and nonequilibrium approaches will have decisive roles and where productive teamwork among elements of modeling, simulations, synthesis, characterization and applications could be anticipated--particularly multiscale and nonequilibrium phenomena, and complex matter in and between fields of soft, hard and biomimetic materials. Principal topics were: (i) Complex organic and inorganic electronic materials, including hard, soft and biomimetic materials, self-assembly processes and photophysics; (ii) Microstructure and evolution in multiscale and hierarchical materials, including dynamic fracture and friction, dislocation and large-scale deformation, metastability, and inhomogeneity; and (iii) Equilibrium and nonequilibrium phases and phase transformations, emphasizing competing interactions, frustration, landscapes, glassy and stochastic dynamics, and energy focusing.

  18. Security Analysis of Selected AMI Failure Scenarios Using Agent Based Game Theoretic Simulation

    SciTech Connect (OSTI)

    Abercrombie, Robert K [ORNL] [ORNL; Schlicher, Bob G [ORNL] [ORNL; Sheldon, Frederick T [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    Information security analysis can be performed using game theory implemented in dynamic Agent Based Game Theoretic (ABGT) simulations. Such simulations can be verified with the results from game theory analysis and further used to explore larger scale, real world scenarios involving multiple attackers, defenders, and information assets. We concentrated our analysis on the Advanced Metering Infrastructure (AMI) functional domain which the National Electric Sector Cyber security Organization Resource (NESCOR) working group has currently documented 29 failure scenarios. The strategy for the game was developed by analyzing five electric sector representative failure scenarios contained in the AMI functional domain. From these five selected scenarios, we characterize them into three specific threat categories affecting confidentiality, integrity and availability (CIA). The analysis using our ABGT simulation demonstrates how to model the AMI functional domain using a set of rationalized game theoretic rules decomposed from the failure scenarios in terms of how those scenarios might impact the AMI network with respect to CIA.

  19. Non-Stationary Random Process for Large-Scale Failure and Recovery of Power Distributions

    E-Print Network [OSTI]

    Wei, Yun; Galvan, Floyd; Couvillon, Stephen; Orellana, George; Momoh, James

    2012-01-01T23:59:59.000Z

    A key objective of the smart grid is to improve reliability of utility services to end users. This requires strengthening resilience of distribution networks that lie at the edge of the grid. However, distribution networks are exposed to external disturbances such as hurricanes and snow storms where electricity service to customers is disrupted repeatedly. External disturbances cause large-scale power failures that are neither well-understood, nor formulated rigorously, nor studied systematically. This work studies resilience of power distribution networks to large-scale disturbances in three aspects. First, a non-stationary random process is derived to characterize an entire life cycle of large-scale failure and recovery. Second, resilience is defined based on the non-stationary random process. Close form analytical expressions are derived under specific large-scale failure scenarios. Third, the non-stationary model and the resilience metric are applied to a real life example of large-scale disruptions due t...

  20. Impact of defects on the electrical transport, optical properties and failure mechanisms of GaN nanowires.

    SciTech Connect (OSTI)

    Armstrong, Andrew M.; Aubry, Sylvie; Shaner, Eric Arthur; Siegal, Michael P.; Li, Qiming; Jones, Reese E.; Westover, Tyler; Wang, George T.; Zhou, Xiao Wang; Talin, Albert Alec; Bogart, Katherine Huderle Andersen; Harris, C. Thomas; Huang, Jian Yu

    2010-09-01T23:59:59.000Z

    We present the results of a three year LDRD project that focused on understanding the impact of defects on the electrical, optical and thermal properties of GaN-based nanowires (NWs). We describe the development and application of a host of experimental techniques to quantify and understand the physics of defects and thermal transport in GaN NWs. We also present the development of analytical models and computational studies of thermal conductivity in GaN NWs. Finally, we present an atomistic model for GaN NW electrical breakdown supported with experimental evidence. GaN-based nanowires are attractive for applications requiring compact, high-current density devices such as ultraviolet laser arrays. Understanding GaN nanowire failure at high-current density is crucial to developing nanowire (NW) devices. Nanowire device failure is likely more complex than thin film due to the prominence of surface effects and enhanced interaction among point defects. Understanding the impact of surfaces and point defects on nanowire thermal and electrical transport is the first step toward rational control and mitigation of device failure mechanisms. However, investigating defects in GaN NWs is extremely challenging because conventional defect spectroscopy techniques are unsuitable for wide-bandgap nanostructures. To understand NW breakdown, the influence of pre-existing and emergent defects during high current stress on NW properties will be investigated. Acute sensitivity of NW thermal conductivity to point-defect density is expected due to the lack of threading dislocation (TD) gettering sites, and enhanced phonon-surface scattering further inhibits thermal transport. Excess defect creation during Joule heating could further degrade thermal conductivity, producing a viscous cycle culminating in catastrophic breakdown. To investigate these issues, a unique combination of electron microscopy, scanning luminescence and photoconductivity implemented at the nanoscale will be used in concert with sophisticated molecular-dynamics calculations of surface and defect-mediated NW thermal transport. This proposal seeks to elucidate long standing material science questions for GaN while addressing issues critical to realizing reliable GaN NW devices.

  1. Practical Formal Verification of Diagnosability of Large Models

    E-Print Network [OSTI]

    Bonaventure, Olivier

    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.4.1 Failure Scenario 1: PV03 stuck closed . . . . . . . . . . . 11 5.4.2 Failure Scenario 6: SV of real plants. Section 3 describes how these plants are modeled, and how models can be sim- plified

  2. Argonne National Laboratory Investigates Premature Bearing Failures...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of this investigation were recently published in the peer-reviewed journal Wear, titled "Material Wear and Fatigue in Wind Turbine Systems" and presented at the corresponding Wear...

  3. Hardfacing material

    DOE Patents [OSTI]

    Branagan, Daniel J. (Iona, ID)

    2012-01-17T23:59:59.000Z

    A method of producing a hard metallic material by forming a mixture containing at least 55% iron and at least one of boron, carbon, silicon and phosphorus. The mixture is formed into an alloy and cooled to form a metallic material having a hardness of greater than about 9.2 GPa. The invention includes a method of forming a wire by combining a metal strip and a powder. The metal strip and the powder are rolled to form a wire containing at least 55% iron and from two to seven additional elements including at least one of C, Si and B. The invention also includes a method of forming a hardened surface on a substrate by processing a solid mass to form a powder, applying the powder to a surface to form a layer containing metallic glass, and converting the glass to a crystalline material having a nanocrystalline grain size.

  4. Clinical investigation: Regional nodal failure patterns in breast cancer patients treated with mastectomy without radiotherapy

    SciTech Connect (OSTI)

    Strom, Eric A. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States)]. E-mail: estrom@mdanderson.org; Woodward, Wendy A. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Katz, Angela [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Buchholz, Thomas A. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Perkins, George H. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Jhingran, Anuja [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Theriault, Richard [Department of Medical Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Singletary, Eva [Department of Surgical Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Sahin, Aysegul [Department of Pathology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); McNeese, Marsha D. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States)

    2005-12-01T23:59:59.000Z

    Purpose: The purpose of this study was to describe regional nodal failure patterns in patients who had undergone mastectomy with axillary dissection to define subgroups of patients who might benefit from supplemental regional nodal radiation to the axilla or supraclavicular fossa/axillary apex. Methods and Materials: The cohort consisted of 1031 patients treated with mastectomy (including a level I-II axillary dissection) and doxorubicin-based systemic therapy without radiation on five clinical trials at M.D. Anderson Cancer Center. Patient records, including pathology reports, were retrospectively reviewed. All regional recurrences (with or without distant metastasis) were recorded. Median follow-up was 116 months (range, 6-262 months). Results: Twenty-one patients recurred within the low-mid axilla (10-year actuarial rate 3%). Of these, 16 were isolated regional failures (no chest wall failure). The risk of failure in the low-mid axilla was not significantly higher for patients with increasing numbers of involved nodes, increasing percentage of involved nodes, larger nodal size or gross extranodal extension. Only 3 of 100 patients with <10 nodes examined recurred in the low-mid axilla. Seventy-seven patients had a recurrence in the supraclavicular fossa/axillary apex (10-year actuarial rate 8%). Forty-nine were isolated regional recurrences. Significant predictors of failures in this region included {>=}4 involved axillary lymph nodes, >20% involved axillary nodes, and the presence of gross extranodal extension (10-year actuarial rates 15%, 14%, and 19%, respectively, p < 0.0005). The extent of axillary dissection and the size of the largest involved node were not predictive of failure within the supraclavicular fossa/axillary apex. Conclusions: These results suggest that failure in the level I-II axilla is an uncommon occurrence after modified radical mastectomy and chemotherapy. Therefore, supplemental radiotherapy to the dissected axilla is not warranted for most patients. However, patients with {>=}4 involved axillary lymph nodes, >20% involved axillary nodes, or gross extranodal extension are at increased risk of failure in the supraclavicular fossa/axillary apex and should receive radiation to undissected regions in addition to the chest wall.

  5. Nuclear fuel elements made from nanophase materials

    DOE Patents [OSTI]

    Heubeck, Norman B. (Schenectady, NY)

    1998-01-01T23:59:59.000Z

    A nuclear reactor core fuel element is composed of nanophase high temperature materials. An array of the fuel elements in rod form are joined in an open geometry fuel cell that preferably also uses such nanophase materials for the cell structures. The particular high temperature nanophase fuel element material must have the appropriate mechanical characteristics to avoid strain related failure even at high temperatures, in the order of about 3000.degree. F. Preferably, the reactor type is a pressurized or boiling water reactor and the nanophase material is a high temperature ceramic or ceramic composite. Nanophase metals, or nanophase metals with nanophase ceramics in a composite mixture, also have desirable characteristics, although their temperature capability is not as great as with all-ceramic nanophase material. Combinations of conventional or nanophase metals and conventional or nanophase ceramics can be employed as long as there is at least one nanophase material in the composite. The nuclear reactor so constructed has a number of high strength fuel particles, a nanophase structural material for supporting a fuel rod at high temperature, a configuration to allow passive cooling in the event of a primary cooling system failure, an ability to retain a coolable geometry even at high temperatures, an ability to resist generation of hydrogen gas, and a configuration having good nuclear, corrosion, and mechanical characteristics.

  6. Nuclear fuel elements made from nanophase materials

    DOE Patents [OSTI]

    Heubeck, N.B.

    1998-09-08T23:59:59.000Z

    A nuclear reactor core fuel element is composed of nanophase high temperature materials. An array of the fuel elements in rod form are joined in an open geometry fuel cell that preferably also uses such nanophase materials for the cell structures. The particular high temperature nanophase fuel element material must have the appropriate mechanical characteristics to avoid strain related failure even at high temperatures, in the order of about 3000 F. Preferably, the reactor type is a pressurized or boiling water reactor and the nanophase material is a high temperature ceramic or ceramic composite. Nanophase metals, or nanophase metals with nanophase ceramics in a composite mixture, also have desirable characteristics, although their temperature capability is not as great as with all-ceramic nanophase material. Combinations of conventional or nanophase metals and conventional or nanophase ceramics can be employed as long as there is at least one nanophase material in the composite. The nuclear reactor so constructed has a number of high strength fuel particles, a nanophase structural material for supporting a fuel rod at high temperature, a configuration to allow passive cooling in the event of a primary cooling system failure, an ability to retain a coolable geometry even at high temperatures, an ability to resist generation of hydrogen gas, and a configuration having good nuclear, corrosion, and mechanical characteristics. 5 figs.

  7. Materials Degradation in Light Water Reactors: Life After 60,???

    SciTech Connect (OSTI)

    Busby, Jeremy T [ORNL; Nanstad, Randy K [ORNL; Stoller, Roger E [ORNL; Feng, Zhili [ORNL; Naus, Dan J [ORNL

    2008-04-01T23:59:59.000Z

    Nuclear reactors present a very harsh environment for components service. Components within a reactor core must tolerate high temperature water, stress, vibration, and an intense neutron field. Degradation of materials in this environment can lead to reduced performance, and in some cases, sudden failure. A recent EPRI-led study interviewed 47 US nuclear utility executives to gauge perspectives on long-term operation of nuclear reactors. Nearly 90% indicated that extensions of reactor lifetimes to beyond 60 years were likely. When polled on the most challenging issues facing further life extension, two-thirds cited plant reliability as the key issue with materials aging and cable/piping as the top concerns for plant reliability. Materials degradation within a nuclear power plant is very complex. There are many different types of materials within the reactor itself: over 25 different metal alloys can be found with can be found within the primary and secondary systems, not to mention the concrete containment vessel, instrumentation and control, and other support facilities. When this diverse set of materials is placed in the complex and harsh environment coupled with load, degradation over an extended life is indeed quite complicated. To address this issue, the USNRC has developed a Progressive Materials Degradation Approach (NUREG/CR-6923). This approach is intended to develop a foundation for appropriate actions to keep materials degradation from adversely impacting component integrity and safety and identify materials and locations where degradation can reasonably be expected in the future. Clearly, materials degradation will impact reactor reliability, availability, and potentially, safe operation. Routine surveillance and component replacement can mitigate these factors, although failures still occur. With reactor life extensions to 60 years or beyond or power uprates, many components must tolerate the reactor environment for even longer times. This may increase susceptibility for most components and may introduce new degradation modes. While all components (except perhaps the reactor vessel) can be replaced, it may not be economically favorable. Therefore, understanding, controlling, and mitigating materials degradation processes are key priorities for reactor operation, power uprate considerations, and life extensions. This document is written to give an overview of some of the materials degradation issues that may be key for extend reactor service life. A detailed description of all the possible forms of degradation is beyond the scope of this short paper and has already been described in other documents (for example, the NUREG/CR-6923). The intent of this document is to present an overview of current materials issues in the existing reactor fleet and a brief analysis of the potential impact of extending life beyond 60 years. Discussion is presented in six distinct areas: (1) Reactor pressure vessel; (2) Reactor core and primary systems; (3) Reactor secondary systems; (4) Weldments; (5) Concrete; and (6) Modeling and simulations. Following each of these areas, some research thrust directions to help identify and mitigate lifetime extension issues are proposed. Note that while piping and cabling are important for extended service, these components are discussed in more depth in a separate paper. Further, the materials degradation issues associated with fuel cladding and fuel assemblies are not discussed in this section as these components are replaced periodically and will not influence the overall lifetime of the reactor.

  8. Are Disks the Dominant Contributor for Storage Failures? A Comprehensive Study of Storage Subsystem Failure Characteristics

    E-Print Network [OSTI]

    Zhou, Yuanyuan

    Are Disks the Dominant Contributor for Storage Failures? A Comprehensive Study of Storage Subsystem Appliance, Inc. arkady@netapp.com Abstract Building reliable storage systems becomes increas- ingly characteristics is crucially important for designing and building a reliable storage system. While several re

  9. Investigation into the failure cause of a double-acting, leading-edge-groove, tilting-pad thrust bearing. Final report, Feb-Aug 90

    SciTech Connect (OSTI)

    Peterson, B.K.

    1990-10-01T23:59:59.000Z

    This report describes the results of bench tests simulating operation and failure of a thrust bearing used in a gas turbine engine compressor development test rig. The bearing was a double acting, tilting pad with offset pivot, leading edge groove configuration using an AMS 4928 titanium collar and C18200 copper-chrome alloy pads with a No. 2 babbitt face. The bench tests successfully simulated the bearing failure and demonstrated a materials incompatibility. This was supported by visual examination, scanning electron microscopy and X-ray energy spectroscopy. A comparison of the bench test results to the compressor rig bearing failure is provided to support the report conclusions.

  10. CONTAINER MATERIALS, FABRICATION AND ROBUSTNESS

    SciTech Connect (OSTI)

    Dunn, K.; Louthan, M.; Rawls, G.; Sindelar, R.; Zapp, P.; Mcclard, J.

    2009-11-10T23:59:59.000Z

    The multi-barrier 3013 container used to package plutonium-bearing materials is robust and thereby highly resistant to identified degradation modes that might cause failure. The only viable degradation mechanisms identified by a panel of technical experts were pressurization within and corrosion of the containers. Evaluations of the container materials and the fabrication processes and resulting residual stresses suggest that the multi-layered containers will mitigate the potential for degradation of the outer container and prevent the release of the container contents to the environment. Additionally, the ongoing surveillance programs and laboratory studies should detect any incipient degradation of containers in the 3013 storage inventory before an outer container is compromised.

  11. Development of an Extreme Environment Materials Research Facility at Princeton

    SciTech Connect (OSTI)

    Cohen, A B; Tully, C G; Austin, R; Calaprice, F; McDonald, K; Ascione, G; Baker, G; Davidson, R; Dudek, L; Grisham, L; Kugel, H; Pagdon, K; Stevenson, T; Woolley, R

    2010-11-17T23:59:59.000Z

    The need for a fundamental understanding of material response to a neutron and/or high heat flux environment can yield development of improved materials and operations with existing materials. Such understanding has numerous applications in fields such as nuclear power (for the current fleet and future fission and fusion reactors), aerospace, and other research fields (e.g., high-intensity proton accelerator facilities for high energy physics research). A proposal has been advanced to develop a facility for testing various materials under extreme heat and neutron exposure conditions at Princeton. The Extreme Environment Materials Research Facility comprises an environmentally controlled chamber (48 m^3) capable of high vacuum conditions, with extreme flux beams and probe beams accessing a central, large volume target. The facility will have the capability to expose large surface areas (1 m^2) to 14 MeV neutrons at a fluence in excess of 10^13 n/s. Depending on the operating mode. Additionally beam line power on the order of 15-75 MW/m2 for durations of 1-15 seconds are planned... The multi-second duration of exposure can be repeated every 2-10 minutes for periods of 10-12 hours. The facility will be housed in the test cell that held the Tokamak Fusion Test Reactor (TFTR), which has the desired radiation and safety controls as well as the necessary loading and assembly infrastructure. The facility will allow testing of various materials to their physical limit of thermal endurance and allow for exploring the interplay between radiation-induced embrittlement, swelling and deformation of materials, and the fatigue and fracturing that occur in response to thermal shocks. The combination of high neutron energies and intense fluences will enable accelerated time scale studies. The results will make contributions for refining predictive failure modes (modeling) in extreme environments, as well as providing a technical platform for the development of new alloys, new materials, and the investigation of repair mechanisms. Effects on materials will be analyzed with in situ beam probes and instrumentation as the target is exposed to radiation, thermal fluxes and other stresses. Photon and monochromatic neutron fluxes, produced using a variable-energy (4-45 MeV) electron linac and the highly asymmetric electron-positron collisions technique used in high-energy physics research, can provide non-destructive, deep-penetrating structural analysis of materials while they are undergoing testing. The same beam lines will also be able to generate neutrons from photonuclear interactions using existing Bremsstrahlung and positrons on target quasi-monochromatic gamma rays. Other diagnostics will include infrared cameras, residual gas analyzer (RGA), and thermocouples; additional diagnostic capability will be added.

  12. Description and evaluation of a mechanistically based conceptual model for spall

    SciTech Connect (OSTI)

    Hansen, F.D.; Knowles, M.K.; Thompson, T.W. [and others

    1997-08-01T23:59:59.000Z

    A mechanistically based model for a possible spall event at the WIPP site is developed and evaluated in this report. Release of waste material to the surface during an inadvertent borehole intrusion is possible if future states of the repository include high gas pressure and waste material consisting of fine particulates having low mechanical strength. The conceptual model incorporates the physics of wellbore hydraulics coupled to transient gas flow to the intrusion borehole, and mechanical response of the waste. Degraded waste properties using of the model. The evaluations include both numerical and analytical implementations of the conceptual model. A tensile failure criterion is assumed appropriate for calculation of volumes of waste experiencing fragmentation. Calculations show that for repository gas pressures less than 12 MPa, no tensile failure occurs. Minimal volumes of material experience failure below gas pressure of 14 MPa. Repository conditions dictate that the probability of gas pressures exceeding 14 MPa is approximately 1%. For these conditions, a maximum failed volume of 0.25 m{sup 3} is calculated.

  13. Atomistc Models of LMRNMC Materials

    Broader source: Energy.gov (indexed) [DOE]

    June 19, 2014 25 Technical Back-Up Slides H.I. a nd R.B. AMR June 19, 2014 26 Li 2 MnO 3 Bulk (3-Li & 1-O vac. Far from tet. Mn site): Mn-K edge TT Mn Vo TT (4) 5 6 * Increase...

  14. Making, Measuring, and Modeling Materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recovery challenge fund Las ConchasTrail5,722,326 Site advancesTP-6A20-62566 O

  15. Materials Science & Tech Division | Advanced Materials | ORNL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Science and Technology SHARE Materials Science and Technology Division The Materials Science and Technology Division is unique within the Department of Energy (DOE)...

  16. Failure Forewarning in NPP Equipment NERI2000-109 Final Project Report

    SciTech Connect (OSTI)

    Hively, LM

    2004-03-26T23:59:59.000Z

    The objective of this project is forewarning of machine failures in critical equipment at next-generation nuclear power plants (NPP). Test data were provided by two collaborating institutions: Duke Engineering and Services (first project year), and the Pennsylvania State University (Applied Research Laboratory) during the second and third project years. New nonlinear methods were developed and applied successfully to extract forewarning trends from process-indicative, time-serial data for timely, condition-based maintenance. Anticipation of failures in critical equipment at next-generation NPP will improve the scheduling of maintenance activities to minimize safety concerns, unscheduled non-productive downtime, and collateral damage due to unexpected failures. This approach provides significant economic benefit, and is expected to improve public acceptance of nuclear power. The approach is a multi-tiered, model-independent, and data-driven analysis that uses ORNL's novel nonlinear method to extract forewarning of machine failures from appropriate data. The first tier of the analysis provides a robust choice for the process-indicative data. The second tier rejects data of inadequate quality. The third tier removes signal artifacts that would otherwise confound the analysis, while retaining the relevant nonlinear dynamics. The fourth tier converts the artifact-filtered time-serial data into a geometric representation, that is then transformed to a discrete distribution function (DF). This method allows for noisy, finite-length datasets. The fifth tier obtains dissimilarity measures (DM) between the nominal-state DF and subsequent test-state DFs. Forewarning of a machine failure is indicated by several successive occurrences of the DM above a threshold, or by a statistically significant trend in the DM. This paradigm yields robust nonlinear signatures of degradation and its progression, allowing earlier and more accurate detection of the machine failure.

  17. Link failure detection in a parallel computer

    DOE Patents [OSTI]

    Archer, Charles J. (Rochester, MN); Blocksome, Michael A. (Rochester, MN); Megerian, Mark G. (Rochester, MN); Smith, Brian E. (Rochester, MN)

    2010-11-09T23:59:59.000Z

    Methods, apparatus, and products are disclosed for link failure detection in a parallel computer including compute nodes connected in a rectangular mesh network, each pair of adjacent compute nodes in the rectangular mesh network connected together using a pair of links, that includes: assigning each compute node to either a first group or a second group such that adjacent compute nodes in the rectangular mesh network are assigned to different groups; sending, by each of the compute nodes assigned to the first group, a first test message to each adjacent compute node assigned to the second group; determining, by each of the compute nodes assigned to the second group, whether the first test message was received from each adjacent compute node assigned to the first group; and notifying a user, by each of the compute nodes assigned to the second group, whether the first test message was received.

  18. Component failure data handbook. Technical evaluation report

    SciTech Connect (OSTI)

    Gentillon, C.D.

    1991-04-01T23:59:59.000Z

    This report presents generic component failure rates that are used in reliability and risk studies of commercial nuclear power plants. The rates are computed using plant-specific data from published probabilistic risk assessments supplemented by selected other sources. Each data source is described. For rates with four or more separate estimates among the sources, plots show the data that are combined. The method for combining data from different sources is presented. The resulting aggregated rates are listed with upper bounds that reflect the variability observed in each rate across the nuclear power plant industry. Thus, the rates are generic. Both per hour and per demand rates are included. They may be used for screening in risk assessments or for forming distributions to be updated with plant-specific data.

  19. Log-periodic behavior of a hierarchical failure model with ...

    E-Print Network [OSTI]

    Departments of Earth and Space Sciences, Physics and Astronomy, and Mathematics, University of ..... tem is continuous but the energy loss is in a discrete set.

  20. SciTech Connect: Modeling Thermally Induced Failure of Brittle...

    Office of Scientific and Technical Information (OSTI)

    Content: Close Send 0 pages in this document matching the terms "" Search For Terms: Enter terms in the toolbar above to search the full text of this document for pages...

  1. A Numeric Predictive Failure Model for Percussive Excavation

    E-Print Network [OSTI]

    Green, Alex Nicholas

    2011-01-01T23:59:59.000Z

    Densities, 500, 1250, and 1750 BPM, 70 mm Depth, 5 mm/s, ODensities, 0,500, and 1750 BPM, 70 mm Depth, 5 mm/s, 90 Ofrom 4.16 Hz to 29.16 Hz (250 BPM – 1750 BPM). In order to

  2. Impact of Fuel Failure on Criticality Safety of Used Nuclear Fuel

    SciTech Connect (OSTI)

    Marshall, William BJ J [ORNL] [ORNL; Wagner, John C [ORNL] [ORNL

    2012-01-01T23:59:59.000Z

    Commercial used nuclear fuel (UNF) in the United States is expected to remain in storage for considerably longer periods than originally intended (e.g., <40 years). Extended storage (ES) time and irradiation of nuclear fuel to high-burnup values (>45 GWd/t) may increase the potential for fuel failure during normal and accident conditions involving storage and transportation. Fuel failure, depending on the severity, can result in changes to the geometric configuration of the fuel, which has safety and regulatory implications. The likelihood and extent of fuel reconfiguration and its impact on the safety of the UNF is not well understood. The objective of this work is to assess and quantify the impact of fuel reconfiguration due to fuel failure on criticality safety of UNF in storage and transportation casks. This effort is primarily motivated by concerns related to the potential for fuel degradation during ES periods and transportation following ES. The criticality analyses consider representative UNF designs and cask systems and a range of fuel enrichments, burnups, and cooling times. The various failed-fuel configurations considered are designed to bound the anticipated effects of individual rod and general cladding failure, fuel rod deformation, loss of neutron absorber materials, degradation of canister internals, and gross assembly failure. The results quantify the potential impact on criticality safety associated with fuel reconfiguration and may be used to guide future research, design, and regulatory activities. Although it can be concluded that the criticality safety impacts of fuel reconfiguration during transportation subsequent to ES are manageable, the results indicate that certain configurations can result in a large increase in the effective neutron multiplication factor, k{sub eff}. Future work to inform decision making relative to which configurations are credible, and therefore need to be considered in a safety evaluation, is recommended.

  3. Fundamental Approach to Electrode Fabrication and Failure Analysis

    Broader source: Energy.gov (indexed) [DOE]

    Fundamental Approach to Electrode Fabrication and Failure Analysis Vince Battaglia LBNL May 11, 2011 This presentation does not contain any proprietary, confidential, or otherwise...

  4. GROUND PLANE INSULATION FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

    FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL M. A. Green,Time Projection Cnamber) thin superconducting solenoid. Theand breakage of the superconductor. The UPA circuit melted

  5. White-Etching Crack Failure Overview, Tomography Analysis, and...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    White-Etching Crack Failure Overview, Tomography Analysis, and Test Development Presented by Aaron Greco of Argonne National Laboratory at the Wind Turbine Tribology Seminar 2014....

  6. Investigations of Bearing Failures Associated with White Etching...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of Bearing Failures Associated with White Etching Areas (irWEAs) in Wind Turbine Gearboxes Presented by Bob Errichello of GEARTECH at the Wind Turbine Tribology...

  7. acute hepatic failure: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    GEOSYNTHETICS Engineering Websites Summary: failure involving a reinforced geosynthetic clay liner in a sedimentation pond at a waste containment liners to hydrate during on-site...

  8. arrester failure rate: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    GEOSYNTHETICS Engineering Websites Summary: failure involving a reinforced geosynthetic clay liner in a sedimentation pond at a waste containment liners to hydrate during on-site...

  9. antiretroviral therapy failure: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    GEOSYNTHETICS Engineering Websites Summary: failure involving a reinforced geosynthetic clay liner in a sedimentation pond at a waste containment liners to hydrate during on-site...

  10. acute liver failure: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    GEOSYNTHETICS Engineering Websites Summary: failure involving a reinforced geosynthetic clay liner in a sedimentation pond at a waste containment liners to hydrate during on-site...

  11. acute renal failure: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    GEOSYNTHETICS Engineering Websites Summary: failure involving a reinforced geosynthetic clay liner in a sedimentation pond at a waste containment liners to hydrate during on-site...

  12. antiretroviral drug failure: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    GEOSYNTHETICS Engineering Websites Summary: failure involving a reinforced geosynthetic clay liner in a sedimentation pond at a waste containment liners to hydrate during on-site...

  13. adult respiratory failure: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    GEOSYNTHETICS Engineering Websites Summary: failure involving a reinforced geosynthetic clay liner in a sedimentation pond at a waste containment liners to hydrate during on-site...

  14. Solar Cell/Module Degradation and Failure Diagnostics

    SciTech Connect (OSTI)

    McMahon, T.J.

    2008-01-01T23:59:59.000Z

    Solar cell/module degradation and failure diagnostics are reviewed. Cell and packaging failure are distinguished. Failure relevant to photovoltaics(PV) is caused by and can be accelerated with each or combination of each of the following stresses: temperature, voltage, moisture, current, and thermal cycling. Failure mechanisms for the different module technologies are summarized. Diagnostic tools for locating the affected area within a large-area module are pointed out along with the importance of interpretation of the visual appearance of the different damage mechanisms.

  15. Tribological Analysis of White Etching Crack (WEC) Failures in...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Crack (WEC) Failures in Rolling Element Bearings Presented by Arnaud Ruellan, INSA de Lyon at the Wind Turbine Tribology Seminar 2014. 20141030NREL2014ArgonneRuellancomV...

  16. GROUND PLANE INSULATION FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

    FAILURE IN THE FIRST TPC SUPERCONDUCTING COIL M. A. Green,Time Projection Cnamber) thin superconducting solenoid. Thefailure of the first superconducting coil at the Lawrence

  17. Wind Turbine Gearbox Failure Modes - A Brief (Presentation)

    SciTech Connect (OSTI)

    Sheng, S.; McDade, M.; Errichello, R.

    2011-10-01T23:59:59.000Z

    Wind turbine gearboxes are not always meeting 20-year design life. Premature failure of gearboxes increases cost of energy, turbine downtime, unplanned maintenance, gearbox replacement and rebuild, and increased warranty reserves. The problem is widespread, affects most Original Equipment Manufacturers, and is not caused by manufacturing practices. There is a need to improve gearbox reliability and reduce turbine downtime. The topics of this presentation are: GRC (Gearbox Reliability Collaborative) technical approach; Gearbox failure database; Recorded incidents summary; Top failure modes for bearings; Top failure modes for gears; GRC test gearbox; Bearing nomenclature; Test history; Real damage; Gear sets; Bearings; Observations; and Summary. 5 refs.

  18. Structural Analysis of Human and Bovine Bone for Development of Synthetic Materials

    E-Print Network [OSTI]

    Jang, Eunhwa

    2012-10-19T23:59:59.000Z

    bones, as well as mimicking nature by developing a synthetic material to repair bones. Experimentally, bovine bone, tumor-free human bone, and cancerous human bone were studied via the small scale mechanical loading test. Failure analysis was conducted...

  19. Journal of Nuclear Materials 187(1992) 1-31 North-Holland

    E-Print Network [OSTI]

    Raffray, A. René

    1992-01-01T23:59:59.000Z

    tritium inventories 1. Introduction Interest in the use of solid lithium-based materials as tritium/multiplier thermomechanical behavior Corrosion and mass transfer Structural response and failure modes in fusion environment

  20. "Tablet-level Origin of Toughening in Abalone Shells and Translation to Synthetic Nanocomposite Materials"

    E-Print Network [OSTI]

    Ghosh, Somnath

    bio-inspired nanocomposites. In particular, the development of a nacre-like material, fabricated by 3D printing and exhibiting similar failure modes, will be presented. Then, I will discuss the nanomechanics

  1. Dissimilar-weld failure analysis and development. Comparative behavior of similar and dissimilar welds. Final report. [Welds of 2-1/4Cr-1Mo to 2-1/4Cr-1Mo using 2-1/4Cr-1Mo filler material; and austenitic to ferritic steel welds made by fusion welding alloy-800H to 2-1/4Cr-1Mo using nickel base filler metal ERNiCr-3

    SciTech Connect (OSTI)

    Busboom, H.; Ring, P.J.

    1986-07-01T23:59:59.000Z

    The 593/sup 0/C (1100/sup 0/F) stress rupture behavior of similar metal welds (SMWs) and dissimilar metal welds (DMWs) was investigated under cyclic load and cyclic temperature conditions to provide insight into the question, ''Why do DMWs fail sooner than SMWs in the fossil fuel boilers.'' The weld joints of interest were an all ferritic steel SMW made by fusion welding 2-1/4Cr-1Mo to 2-1/4Cr-1Mo using 2-1/4Cr-1Mo filler metal and an austenitic to ferritic steel DMW made by fusion welding Alloy-800H to 2-1/4Cr-1Mo using a nickel base filler metal ERNiCr-3. The stress rupture behavior obtained on cross weld specimens was similar for both types of welds with only a 20% reduction in rupture life for the DMW. For rupture times less than 1500 hours, failures occurred in the 2-1/4Cr-1Mo base metal whereas, for rupture times greater than 1500 hours, failures occurred in the 2-1/4Cr-1Mo heat affected zone (HAZ). The HAZ failures exhibited a more brittle appearance than the base metal failures for both types of welds and it appears that the life of both joints was limited by the stress rupture properties of the HAZ. These results support the hypothesis that increased residual stresses due to abrupt changes in hardness (strength) of metals involved are the major contributors to the reduction in life of DMWs as compared to SMWs. 10 refs., 15 figs., 7 tabs.

  2. The role of â-adrenergic signaling in heart failure. : Why do betablockers have beneficial effects in heart failure?.

    E-Print Network [OSTI]

    Haga, Møyfrid

    2007-01-01T23:59:59.000Z

    ??Background In heart failure, the heart does not pump out enough blood to satisfy the body tissues with oxygen. Well-established lines of evidence suggest that… (more)

  3. Elephant butte powerplant investigation of permanent magnet generator corrosion and bearing failures. Project notes 8450-97-07. Technical memo

    SciTech Connect (OSTI)

    Price, P.; Atwater, P.

    1997-04-01T23:59:59.000Z

    This investigation and report were initiated in response to a request to determine causes for excessive corrosion and premature bearing failures on the Woodward Permanent Magnet Generator (PMG) on the three main generating units at Elephant Butte. All three main generating units were rewound using epoxy-type insulating materials between 1989 and 1991. Plant personnel reported that corrosion and failure rates seemed to accelerate after the new stator windings were installed. This report documents field testing conducted the week of March 10, 1997, to determine if stray electrical currents/voltages were causing the problems. Electrical field test results indicate that accelerated PMG bearing failure and corrosion were not caused by stray voltages or current. Tests were conducted on the main shaft in the turbine pit and on the PMG shaft and housing located atop the exciter shaft.

  4. Casting materials

    DOE Patents [OSTI]

    Chaudhry, Anil R. (Xenia, OH); Dzugan, Robert (Cincinnati, OH); Harrington, Richard M. (Cincinnati, OH); Neece, Faurice D. (Lyndurst, OH); Singh, Nipendra P. (Pepper Pike, OH)

    2011-06-14T23:59:59.000Z

    A foam material comprises a liquid polymer and a liquid isocyanate which is mixed to make a solution that is poured, injected or otherwise deposited into a corresponding mold. A reaction from the mixture of the liquid polymer and liquid isocyanate inside the mold forms a thermally collapsible foam structure having a shape that corresponds to the inside surface configuration of the mold and a skin that is continuous and unbroken. Once the reaction is complete, the foam pattern is removed from the mold and may be used as a pattern in any number of conventional casting processes.

  5. Reference Material

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared at 278, 298,NIST 800-53Reference Materials There are a variety of

  6. Materials Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces andMapping the Nanoscale LandscapeImports 5.90 4.86(NHMFL)X-RayMaterials

  7. A micro to macro approach to polymer matrix composites damage modeling : final LDRD report.

    SciTech Connect (OSTI)

    English, Shawn Allen; Brown, Arthur A.; Briggs, Timothy M.

    2013-12-01T23:59:59.000Z

    Capabilities are developed, verified and validated to generate constitutive responses using material and geometric measurements with representative volume elements (RVE). The geometrically accurate RVEs are used for determining elastic properties and damage initiation and propagation analysis. Finite element modeling of the meso-structure over the distribution of characterizing measurements is automated and various boundary conditions are applied. Plain and harness weave composites are investigated. Continuum yarn damage, softening behavior and an elastic-plastic matrix are combined with known materials and geometries in order to estimate the macroscopic response as characterized by a set of orthotropic material parameters. Damage mechanics and coupling effects are investigated and macroscopic material models are demonstrated and discussed. Prediction of the elastic, damage, and failure behavior of woven composites will aid in macroscopic constitutive characterization for modeling and optimizing advanced composite systems.

  8. Photovoltaic Materials

    SciTech Connect (OSTI)

    Duty, C.; Angelini, J.; Armstrong, B.; Bennett, C.; Evans, B.; Jellison, G. E.; Joshi, P.; List, F.; Paranthaman, P.; Parish, C.; Wereszczak, A.

    2012-10-15T23:59:59.000Z

    The goal of the current project was to help make the US solar industry a world leader in the manufacture of thin film photovoltaics. The overall approach was to leverage ORNL’s unique characterization and processing technologies to gain a better understanding of the fundamental challenges for solar cell processing and apply that knowledge to targeted projects with industry members. ORNL has the capabilities in place and the expertise required to understand how basic material properties including defects, impurities, and grain boundaries affect the solar cell performance. ORNL also has unique processing capabilities to optimize the manufacturing process for fabrication of high efficiency and low cost solar cells. ORNL recently established the Center for Advanced Thin-film Systems (CATS), which contains a suite of optical and electrical characterization equipment specifically focused on solar cell research. Under this project, ORNL made these facilities available to industrial partners who were interested in pursuing collaborative research toward the improvement of their product or manufacturing process. Four specific projects were pursued with industrial partners: Global Solar Energy is a solar industry leader in full scale production manufacturing highly-efficient Copper Indium Gallium diSelenide (CIGS) thin film solar material, cells and products. ORNL worked with GSE to develop a scalable, non-vacuum, solution technique to deposit amorphous or nanocrystalline conducting barrier layers on untextured stainless steel substrates for fabricating high efficiency flexible CIGS PV. Ferro Corporation’s Electronic, Color and Glass Materials (“ECGM”) business unit is currently the world’s largest supplier of metallic contact materials in the crystalline solar cell marketplace. Ferro’s ECGM business unit has been the world's leading supplier of thick film metal pastes to the crystalline silicon PV industry for more than 30 years, and has had operational cells and modules in the field for 25 years. Under this project, Ferro leveraged world leading analytical capabilities at ORNL to characterize the paste-to-silicon interface microstructure and develop high efficiency next generation contact pastes. Ampulse Corporation is developing a revolutionary crystalline-silicon (c-Si) thin-film solar photovoltaic (PV) technology. Utilizing uniquely-textured substrates and buffer materials from the Oak Ridge National Laboratory (ORNL), and breakthroughs in Hot-Wire Chemical Vapor Deposition (HW-CVD) techniques in epitaxial silicon developed at the National Renewable Energy Laboratory (NREL), Ampulse is creating a solar technology that is tunable in silicon thickness, and hence in efficiency and economics, to meet the specific requirements of multiple solar PV applications. This project focused on the development of a high rate deposition process to deposit Si, Ge, and Si1-xGex films as an alternate to hot-wire CVD. Mossey Creek Solar is a start-up company with great expertise in the solar field. The primary interest is to create and preserve jobs in the solar sector by developing high-yield, low-cost, high-efficiency solar cells using MSC-patented and -proprietary technologies. The specific goal of this project was to produce large grain formation in thin, net-shape-thickness mc-Si wafers processed with high-purity silicon powder and ORNL's plasma arc lamp melting without introducing impurities that compromise absorption coefficient and carrier lifetime. As part of this project, ORNL also added specific pieces of equipment to enhance our ability to provide unique insight for the solar industry. These capabilities include a moisture barrier measurement system, a combined physical vapor deposition and sputtering system dedicated to cadmium-containing deposits, adeep level transient spectroscopy system useful for identifying defects, an integrating sphere photoluminescence system, and a high-speed ink jet printing system. These tools were combined with others to study the effect of defects on the performance of crystalline silicon and

  9. Degradation and Failure Characteristics of NPP Containment Protective Coating Systems

    SciTech Connect (OSTI)

    Sindelar, R.L.

    2000-12-01T23:59:59.000Z

    A research program to investigate the performance and potential for failure of Service Level I coating systems used in nuclear power plant containment is in progress. The research activities are aligned to address phenomena important to cause failure as identified by the industry coatings expert panel.

  10. Weibull Prediction Intervals for a Future Number of Failures

    E-Print Network [OSTI]

    Weibull Prediction Intervals for a Future Number of Failures Daniel J. Nordman Dept. of Statistics prediction intervals for the number of failures that will be observed in a future inspec­ tion of a sample­based prediction intervals perform better than the alternatives. Key Words: Coverage probability, Prediction bounds

  11. Weibull Prediction Intervals for a Future Number of Failures

    E-Print Network [OSTI]

    Weibull Prediction Intervals for a Future Number of Failures Daniel J. Nordman Dept. of Statistics prediction intervals for the number of failures that will be observed in a future inspec- tion of a sample-based prediction intervals perform better than the alternatives. Key Words: Coverage probability, Prediction bounds

  12. NetPilot: Automating Datacenter Network Failure Mitigation

    E-Print Network [OSTI]

    NetPilot: Automating Datacenter Network Failure Mitigation Xin Wu Daniel Turner Chao-Chih Chen Duke-on and fast-response online ser- vices have driven modern datacenter networks to undergo tremen- dous growth of critical failures commonly encountered in production datacenter networks. Categories and Subject

  13. Lessons Learned from Failures Involving Geofoam in Roads and Embankments

    E-Print Network [OSTI]

    Horvath, John S.

    Lessons Learned from Failures Involving Geofoam in Roads and Embankments Manhattan College Research July 1999) #12;Lessons Learned from Failures Involving Geofoam in Roads and Embankments Manhattan College Research Report No. CE/GE-99-1 ii This page intentionally left blank. #12;Lessons Learned from

  14. FAILURE MODES AND EFFECTS ANALYSIS Dated: May 27, 2010

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    1 NSTX FAILURE MODES AND EFFECTS ANALYSIS (FMEA) Revision 7 Dated: May 27, 2010 Prepared By: Name.07.13 09:11:02 -04'00' #12;NSTX Failure Modes & Effects Analysis / NSTX-FMEA-71-7 / p. 2 of 120 2 Table

  15. Optimized nanoporous materials.

    SciTech Connect (OSTI)

    Braun, Paul V. (University of Illinois at Urbana-Champaign, Urbana, IL); Langham, Mary Elizabeth; Jacobs, Benjamin W.; Ong, Markus D.; Narayan, Roger J. (North Carolina State University, Raleigh, NC); Pierson, Bonnie E. (North Carolina State University, Raleigh, NC); Gittard, Shaun D. (North Carolina State University, Raleigh, NC); Robinson, David B.; Ham, Sung-Kyoung (Korea Basic Science Institute, Gangneung, South Korea); Chae, Weon-Sik (Korea Basic Science Institute, Gangneung, South Korea); Gough, Dara V. (University of Illinois at Urbana-Champaign, Urbana, IL); Wu, Chung-An Max; Ha, Cindy M.; Tran, Kim L.

    2009-09-01T23:59:59.000Z

    Nanoporous materials have maximum practical surface areas for electrical charge storage; every point in an electrode is within a few atoms of an interface at which charge can be stored. Metal-electrolyte interfaces make best use of surface area in porous materials. However, ion transport through long, narrow pores is slow. We seek to understand and optimize the tradeoff between capacity and transport. Modeling and measurements of nanoporous gold electrodes has allowed us to determine design principles, including the fact that these materials can deplete salt from the electrolyte, increasing resistance. We have developed fabrication techniques to demonstrate architectures inspired by these principles that may overcome identified obstacles. A key concept is that electrodes should be as close together as possible; this is likely to involve an interpenetrating pore structure. However, this may prove extremely challenging to fabricate at the finest scales; a hierarchically porous structure can be a worthy compromise.

  16. Energy Efficiency and Renewables: Market and Behavioral Failures

    ScienceCinema (OSTI)

    James Sweeney

    2010-09-01T23:59:59.000Z

    Thursday, January 28, 2010: Policies to promote renewable energy and energy efficiency have been gaining momentum throughout the world, often justified by environmental and energy security concerns. This presentation first talks about energy efficiency options, then delves into the economic motivation for energy efficiency and renewable energy policies by articulating the classes of relevant behavioral failures and market failures. Such behavioral and market failures may vary intertemporally or atemporally; the temporal structure and the extent of the failures are the critical considerations in the development of energy policies. The talk discusses key policy instruments and assess the extent to which they are well-suited to correct for failures with different structures. http://eetd.lbl.gov/dls/lecture-01-28...

  17. Avoid stainless steel failures in FGD systems

    SciTech Connect (OSTI)

    Mills, J.P.; Schillmoller, C.M.

    1995-11-01T23:59:59.000Z

    Preventing pitting and localized corrosion is the key to success where low maintenance and high reliability are rime considerations in flue-gas desulfurization (FGD) designs. Knowing when to use a stainless steel, and when not to, is crucial. Operating parameters and environmental factors greatly affect alloy performance, especially pH, temperature, and chloride and oxygen levels. Failures of stainless steels can be avoided by understanding their limits in light of these variables. This article will focus on the capabilities of Types 316L, 317L, 317LM, 317LMN, 904L, and 6% Mo stainless steels and their applications, as well as provide details on unique combination of mechanical properties and corrosion resistance of the 22% Cr duplex and 25% Cr super-duplex stainless steels in acid chloride systems. Guidelines will be presented on methods to prevent intergranular corrosion, stress corrosion cracking, and pitting and crevice corrosion, and what process steps can be taken to assure reasonable performance of marginal alloy selections. Emphasis will be on the lime/limestone wet scrubbing process and the quencher/absorber.

  18. Energetic materials at extreme conditions 

    E-Print Network [OSTI]

    Millar, David Iain Archibald

    2011-06-27T23:59:59.000Z

    In order to effectively model the behaviour of energetic materials under operational conditions it is essential to obtain detailed structural information for these compounds at elevated temperature and/or pressures. The ...

  19. Proceedings: International Conference on Boiler Tube Failures and Heat Recovery Steam Generator (HRSG) Tube Failures and Inspections

    SciTech Connect (OSTI)

    None

    2002-10-01T23:59:59.000Z

    Tube failures remain the leading cause of availability loss in conventional fossil plants and combined cycle/heat recovery steam generator (HRSG) plants. These conference proceedings address state-of-the-art practices and techniques worldwide for understanding and reducing tube failures.

  20. Quantum effects and anharmonicity in the H{sub 2}-Li{sup +}-benzene complex: A model for hydrogen storage materials

    SciTech Connect (OSTI)

    Kolmann, Stephen J.; D'Arcy, Jordan H.; Jordan, Meredith J. T., E-mail: m.jordan@chem.usyd.edu.au [School of Chemistry, The University of Sydney, NSW 2006 (Australia)] [School of Chemistry, The University of Sydney, NSW 2006 (Australia)

    2013-12-21T23:59:59.000Z

    Quantum and anharmonic effects are investigated in H{sub 2}-Li{sup +}-benzene, a model for hydrogen adsorption in metal-organic frameworks and carbon-based materials. Three- and 8-dimensional quantum diffusion Monte Carlo (QDMC) and rigid-body diffusion Monte Carlo (RBDMC) simulations are performed on potential energy surfaces interpolated from electronic structure calculations at the M05-2X/6-31+G(d,p) and M05-2X/6-311+G(2df,p) levels of theory using a three-dimensional spline or a modified Shepard interpolation. These calculations investigate the intermolecular interactions in this system, with three- and 8-dimensional 0 K H{sub 2} binding enthalpy estimates, ?H{sub bind} (0 K), being 16.5 kJ mol{sup ?1} and 12.4 kJ mol{sup ?1}, respectively: 0.1 and 0.6 kJ mol{sup ?1} higher than harmonic values. Zero-point energy effects are 35% of the value of ?H{sub bind} (0 K) at M05-2X/6-311+G(2df,p) and cannot be neglected; uncorrected electronic binding energies overestimate ?H{sub bind} (0 K) by at least 6 kJ mol{sup ?1}. Harmonic intermolecular binding enthalpies can be corrected by treating the H{sub 2} “helicopter” and “ferris wheel” rotations as free and hindered rotations, respectively. These simple corrections yield results within 2% of the 8-dimensional anharmonic calculations. Nuclear ground state probability density histograms obtained from the QDMC and RBDMC simulations indicate the H{sub 2} molecule is delocalized above the Li{sup +}-benzene system at 0 K.

  1. Emergence of cooperativity in plasticity of soft glassy materials

    E-Print Network [OSTI]

    Le Bouil Antoine; Amon Axelle; McNamara Sean; Crassous Jérôme

    2014-05-19T23:59:59.000Z

    The elastic coupling between plastic events is generally invoked to interpret plastic properties and failure of amorphous soft glassy materials. We report an experiment where the emergence of a self-organized plastic flow is observed well before the failure. For this we impose an homogeneous stress on a granular material, and measure local deformations for very small strain increments using a light scattering setup. We observe a non-homogeneous strain that appears as transient bands of mesoscopic size and well defined orientation, different from the angle of the macroscopic frictional shear band that appears at failure. The presence and the orientation of those micro-bands may be understood by considering how localized plastic reorganizations redistribute stresses in a surrounding continuous elastic medium. We characterize the lengthscale and persistence of the structure. The presence of plastic events and the mesostructure of the plastic flow are compared to numerical simulations.

  2. Critical Materials Institute

    ScienceCinema (OSTI)

    Alex King

    2013-06-05T23:59:59.000Z

    Ames Laboratory Director Alex King talks about the goals of the Critical Materials Institute in diversifying the supply of critical materials, developing substitute materials, developing tools and techniques for recycling critical materials, and forecasting materials needs to avoid future shortages.

  3. Material selection for electrooptic deflectors

    SciTech Connect (OSTI)

    Not Available

    1988-09-01T23:59:59.000Z

    The selection of a material for a practical device is generally guided by a number of criteria, including cost, size, difficulty of fabrication, durability, driver requirements, and system constraints. A quantitative analysis can usually be made for comparison, or a figure of merit can be computed. In the case of materials for electrooptical (EO) devices the choice is often made based on the availability of materials meeting some minimum system requirement. For fast EO deflectors, where a large number of resolvable spots is required, the choice of materials is quite limited. A model of just such a device is proposed; it is based on the resolution of 400 spots and reasonable boundary conditions. The model predicts that to be successful, an EO material must be chosen that has a linear EO coefficient (r/sub 33/) of at least 336 pm/V. A survey was conducted of the EO materials which are generally available. Based on the model and the survey, Czochralski crystal growth of strontium barium niobate (SBN:60) is recommended. Although SBN:60 does not have the largest EO coefficient, it may be the easiest to grow in the required size and optical quality, thus satisfying the availability criterion. It should be borne in mind that many materials may be grown by this technique and there are many new and potential applications for EO materials. 92 refs., 18 figs., 14 tabs.

  4. Failure of the Shockley-Haynes Mobility Experiment with organic semiconducting materials

    E-Print Network [OSTI]

    Boehme, Hollis Clyde

    1961-01-01T23:59:59.000Z

    in olose proximity on the surface of a germanium block and possess high back-voltage rectifier oharacteristics. The emitter is biased in the forward or high ourrent flow direction snd the oollector is biased in the re- verse or low current flow... probe contact resistance measurements. 7. Typioal current versus voltage curve for pyrene- iodine samples, . . . , . . . , . . . . . . . . 25 8. Typical ourrsnt versus' voltage curve for perylene- iodf ne samples . . . . . . . ? . . . . . . . , 26...

  5. Ris-R-1736 (EN) Cohesive laws for assessment of materials failure

    E-Print Network [OSTI]

    of the initial n n n* 0 egration path, and (b) the quals the area under the traction- er Sørensen et al. [A1 resistance 0J d n , (1-8) on per unit fracture surface area. rovide a way to connect the bridging law ...................................................... 39 5. Mixed-Mode case studies ............................................ 51 6. Future developments

  6. Real-Time Quantitative Imaging of Failure Events in Materials Under Load at

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas ConchasPassive Solar HomePromising Science for1PrincipalRare |Real-Time Chemical Imaging

  7. MATERIALS MANAGEMENT MATERIALS MANAGEMENT -INVENTORY CONTROL

    E-Print Network [OSTI]

    Oliver, Douglas L.

    MATERIALS MANAGEMENT MATERIALS MANAGEMENT - INVENTORY CONTROL Record of Property Transferred from ______ ___________________________________ 2. DEAN (If Applies) ______ ___________________________________ 5. UNIVERSITY DIRECTOR OF MATERIALS MANAGEMENT ______ ___________________________________ 3. HOSPITAL DIRECTOR (If Applies) ______ IF YOU NEED

  8. Gas storage materials, including hydrogen storage materials

    DOE Patents [OSTI]

    Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

    2014-11-25T23:59:59.000Z

    A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material, such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

  9. Gas storage materials, including hydrogen storage materials

    DOE Patents [OSTI]

    Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

    2013-02-19T23:59:59.000Z

    A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

  10. Invariant mechanical properties of calcium-silicate-hydrates (C-H-S) in cement-based materials : instrumented nanoindentation and microporomechanical modeling

    E-Print Network [OSTI]

    Constantinides, Georgios, 1978-

    2006-01-01T23:59:59.000Z

    Random porous solids such as bone and geomaterials exhibit a multiphase composite nature, characterized by water-filled pores of nm- to m-scale diameter. The natural synthesis and operating environments of such materials ...

  11. Functional Materials for Energy | Advanced Materials | ORNL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy Storage Fuel Cells Thermoelectrics Separations Materials Catalysis Sensor Materials Polymers and Composites Carbon Fiber Related Research Chemistry and Physics at...

  12. The Interval to Biochemical Failure Is Prognostic for Metastasis, Prostate Cancer-Specific Mortality, and Overall Mortality After Salvage Radiation Therapy for Prostate Cancer

    SciTech Connect (OSTI)

    Johnson, Skyler, E-mail: Skylerjohn3101@gmail.com [Department of Radiation Oncology, The University of Michigan Medical Center, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, The University of Michigan Medical Center, Ann Arbor, Michigan (United States); Jackson, William; Li, Darren; Song, Yeohan; Foster, Corey; Foster, Ben; Zhou, Jessica; Vainshtein, Jeffrey; Feng, Felix; Hamstra, Daniel [Department of Radiation Oncology, The University of Michigan Medical Center, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, The University of Michigan Medical Center, Ann Arbor, Michigan (United States)

    2013-07-01T23:59:59.000Z

    Purpose: To investigate the utility of the interval to biochemical failure (IBF) after salvage radiation therapy (SRT) after radical prostatectomy (RP) for prostate cancer as a surrogate endpoint for distant metastasis (DM), prostate cancer-specific mortality (PCSM), and overall mortality (OM). Methods and Materials: A retrospective analysis of 575 patients treated with SRT after RP from a single institution. Of those, 250 patients experienced biochemical failure (BF), with the IBF defined as the time from commencement of SRT to BF. The IBF was evaluated by Kaplan-Meier and Cox proportional hazards models for its association with DM, PCSM, and OM. Results: The median follow-up time was 85 (interquartile range [IQR] 49.8-121.1) months, with a median IBF of 16.8 (IQR, 8.5-37.1) months. With a cutoff time of 18 months, as previously used, 129 (52%) of patients had IBF ?18 months. There were no differences among any clinical or pathologic features between those with IBF ? and those with IBF >18 months. On log–rank analysis, IBF ?18 months was prognostic for increased DM (P<.0001, HR 4.9, 95% CI 3.2-7.4), PCSM (P<.0001, HR 4.1, 95% CI 2.4-7.1), and OM (P<.0001, HR 2.7, 95% CI 1.7-4.1). Cox proportional hazards models with adjustment for other clinical variables demonstrated that IBF was independently prognostic for DM (P<.001, HR 4.9), PCSM (P<.0001, HR 4.0), and OM (P<.0001, HR 2.7). IBF showed minimal change in performance regardless of androgen deprivation therapy (ADT) use. Conclusion: After SRT, a short IBF can be used for early identification of patients who are most likely to experience progression to DM, PCSM, and OM. IBF ?18 months may be useful in clinical practice or as an endpoint for clinical trials.

  13. Development of Functionally Graded Materials for Manufacturing Tools and Dies and Industrial Processing Equipment

    SciTech Connect (OSTI)

    Lherbier, Louis, W.; Novotnak, David, J.; Herling, Darrell, R.; Sears, James, W.

    2009-03-23T23:59:59.000Z

    Hot forming processes such as forging, die casting and glass forming require tooling that is subjected to high temperatures during the manufacturing of components. Current tooling is adversely affected by prolonged exposure at high temperatures. Initial studies were conducted to determine the root cause of tool failures in a number of applications. Results show that tool failures vary and depend on the operating environment under which they are used. Major root cause failures include (1) thermal softening, (2) fatigue and (3) tool erosion, all of which are affected by process boundary conditions such as lubrication, cooling, process speed, etc. While thermal management is a key to addressing tooling failures, it was clear that new tooling materials with superior high temperature strength could provide improved manufacturing efficiencies. These efficiencies are based on the use of functionally graded materials (FGM), a new subset of hybrid tools with customizable properties that can be fabricated using advanced powder metallurgy manufacturing technologies. Modeling studies of the various hot forming processes helped identify the effect of key variables such as stress, temperature and cooling rate and aid in the selection of tooling materials for specific applications. To address the problem of high temperature strength, several advanced powder metallurgy nickel and cobalt based alloys were selected for evaluation. These materials were manufactured into tooling using two relatively new consolidation processes. One process involved laser powder deposition (LPD) and the second involved a solid state dynamic powder consolidation (SSDPC) process. These processes made possible functionally graded materials (FGM) that resulted in shaped tooling that was monolithic, bi-metallic or substrate coated. Manufacturing of tooling with these processes was determined to be robust and consistent for a variety of materials. Prototype and production testing of FGM tooling showed the benefits of the nickel and cobalt based powder metallurgy alloys in a number of applications evaluated. Improvements in tool life ranged from three (3) to twenty (20) or more times than currently used tooling. Improvements were most dramatic where tool softening and deformation were the major cause of tool failures in hot/warm forging applications. Significant improvement was also noted in erosion of aluminum die casting tooling. Cost and energy savings can be realized as a result of increased tooling life, increased productivity and a reduction in scrap because of improved dimensional controls. Although LPD and SSDPC tooling usually have higher acquisition costs, net tooling costs per component produced drops dramatically with superior tool performance. Less energy is used to manufacture the tooling because fewer tools are required and less recycling of used tools are needed for the hot forming process. Energy is saved during the component manufacturing cycle because more parts can be produced in shorter periods of time. Energy is also saved by minimizing heating furnace idling time because of less downtime for tooling changes.

  14. Congestive heart failure: treat the disease, not the symptom: return to normalcy/Part II--the experimental approach.

    E-Print Network [OSTI]

    Buckberg, Gerald D

    2007-01-01T23:59:59.000Z

    Number: Title: Congestive heart failure: treat the diseaseinvited) TITLE: Congestive heart failure: treat the diseasetreatment of congestive heart failure due to post-infarction

  15. Gearbox Reliability Collaborative Gearbox 1 Failure Analysis Report: December 2010 - January 2011

    SciTech Connect (OSTI)

    Errichello, R.; Muller, J.

    2012-02-01T23:59:59.000Z

    Unintended gearbox failures have a significant impact on the cost of wind farm operations. In 2007, NREL initiated the Gearbox Reliability Collaborative (GRC). The project combines analysis, field testing, dynamometer testing, condition monitoring, and the development and population of a gearbox failure database in a multi-pronged approach to determine why wind turbine gearboxes do not achieve their expected design life. The collaborative of manufacturers, owners, researchers, and consultants focuses on gearbox testing and modeling and the development of a gearbox failure database. Collaborative members also investigate gearbox condition monitoring techniques. Data gained from the GRC will enable designers, developers, and manufacturers to improve gearbox designs and testing standards and create more robust modeling tools. GRC project essentials include the development of two identical, heavily instrumented representative gearbox designs. Knowledge gained from the field and dynamometer tests conducted on these gearboxes builds an understanding of how the selected loads and events translate into bearing and gear response. This report contains the analysis of the first gearbox design.

  16. Reliability analysis for wind turbines with incomplete failure data collected from after the date of initial installation

    E-Print Network [OSTI]

    McCalley, James D.

    Reliability analysis for wind turbines with incomplete failure data collected from after the date model Maximum likelihood Least squares Wind turbines a b s t r a c t Reliability has an impact on wind analysis. In wind energy industry, wind farm operators have greater interest in recording wind turbine

  17. Materials Project: A Materials Genome Approach

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Ceder, Gerbrand (MIT); Persson, Kristin (LBNL)

    Technological innovation - faster computers, more efficient solar cells, more compact energy storage - is often enabled by materials advances. Yet, it takes an average of 18 years to move new materials discoveries from lab to market. This is largely because materials designers operate with very little information and must painstakingly tweak new materials in the lab. Computational materials science is now powerful enough that it can predict many properties of materials before those materials are ever synthesized in the lab. By scaling materials computations over supercomputing clusters, this project has computed some properties of over 80,000 materials and screened 25,000 of these for Li-ion batteries. The computations predicted several new battery materials which were made and tested in the lab and are now being patented. By computing properties of all known materials, the Materials Project aims to remove guesswork from materials design in a variety of applications. Experimental research can be targeted to the most promising compounds from computational data sets. Researchers will be able to data-mine scientific trends in materials properties. By providing materials researchers with the information they need to design better, the Materials Project aims to accelerate innovation in materials research.[copied from http://materialsproject.org/about] You will be asked to register to be granted free, full access.

  18. Reliability Optimization of Redundant Software with Correlated Failures

    E-Print Network [OSTI]

    Gutjahr, Walter

    Reliability Optimization of Redundant Software with Correlated Failures Walter J. Gutjahr \\Lambda of reliability optimization of modular software with redundancy. At present, these approaches seem to be limited to generalize these reliability optimization techniques by taking such correlations explicitly

  19. Failure Mode and Sensitivity Analysis of Gas Lift Valves

    E-Print Network [OSTI]

    Gilbertson, Eric W.

    Gas-lifted oil wells are susceptible to failure through malfunction of gas lift valves. This is a growing concern as offshore wells are drilled thousands of meters below the ocean floor in extreme temperature and pressure ...

  20. The effects of training the biceps brachii muscle to failure

    E-Print Network [OSTI]

    Walker, Donald L., III

    2007-01-01T23:59:59.000Z

    An experimental study was conducted to observe the effects on the size and strength of the biceps brachii muscle of an exercise routine that trained the biceps to failure during each workout. The workout routine used ten ...

  1. Terrestrial Photovoltaic Module Accelerated Test-To-Failure Protocol

    SciTech Connect (OSTI)

    Osterwald, C. R.

    2008-03-01T23:59:59.000Z

    This technical report documents a test-to-failure protocol that may be used to obtain quantitative information about the reliability of photovoltaic modules using accelerated testing in environmental temperature-humidity chambers.

  2. Considerations in Dealing with the Risk of a Compressor Failure

    E-Print Network [OSTI]

    Beals, C. E.

    2007-01-01T23:59:59.000Z

    Many plants do not have sufficient backup compressor capacity and risk having production outages due to compressor failures. Today, system designs are available that can eliminate this risk; however, there is a cost associated with doing so...

  3. Performance of wireless sensor networks under random node failures

    SciTech Connect (OSTI)

    Bradonjic, Milan [Los Alamos National Laboratory; Hagberg, Aric [Los Alamos National Laboratory; Feng, Pan [Los Alamos National Laboratory

    2011-01-28T23:59:59.000Z

    Networks are essential to the function of a modern society and the consequence of damages to a network can be large. Assessing network performance of a damaged network is an important step in network recovery and network design. Connectivity, distance between nodes, and alternative routes are some of the key indicators to network performance. In this paper, random geometric graph (RGG) is used with two types of node failure, uniform failure and localized failure. Since the network performance are multi-facet and assessment can be time constrained, we introduce four measures, which can be computed in polynomial time, to estimate performance of damaged RGG. Simulation experiments are conducted to investigate the deterioration of networks through a period of time. With the empirical results, the performance measures are analyzed and compared to provide understanding of different failure scenarios in a RGG.

  4. Title Slide "Avoiding expensive IT project and product failures

    E-Print Network [OSTI]

    Hatton, Les

    Title Slide "Avoiding expensive IT project and product failures In 21st century healthcare and potential recall of 1 million of its best-selling Camry and Lexus ES300 sedans because of reports

  5. Helium release rates and ODH calculations from RHIC magnet cooling line failure

    SciTech Connect (OSTI)

    Liaw, C.J.; Than, Y.; Tuozzolo, J.

    2011-03-28T23:59:59.000Z

    A catastrophic failure of the magnet cooling lines, similar to the LHC superconducting bus failure incident, could discharge cold helium into the RHIC tunnel and cause an Oxygen Deficiency Hazard (ODH) problem. A SINDA/FLUINT{reg_sign} model, which simulated the 4.5K/4 atm helium flowing through the magnet cooling system distribution lines, then through a line break into the insulating vacuum volumes and discharging via the reliefs into the RHIC tunnel, had been developed. Arc flash energy deposition and heat load from the ambient temperature cryostat surfaces are included in the simulations. Three typical areas: the sextant arc, the Triplet/DX/D0 magnets, and the injection area, had been analyzed. Results, including helium discharge rates, helium inventory loss, and the resulting oxygen concentration in the RHIC tunnel area, are reported. Good agreement had been achieved when comparing the simulation results, a RHIC sector depressurization test measurement, and some simple analytical calculations.

  6. On-clip high frequency reliability and failure test structures

    DOE Patents [OSTI]

    Snyder, E.S.; Campbell, D.V.

    1997-04-29T23:59:59.000Z

    Self-stressing test structures for realistic high frequency reliability characterizations. An on-chip high frequency oscillator, controlled by DC signals from off-chip, provides a range of high frequency pulses to test structures. The test structures provide information with regard to a variety of reliability failure mechanisms, including hot-carriers, electromigration, and oxide breakdown. The system is normally integrated at the wafer level to predict the failure mechanisms of the production integrated circuits on the same wafer. 22 figs.

  7. On-clip high frequency reliability and failure test structures

    DOE Patents [OSTI]

    Snyder, Eric S. (Albuquerque, NM); Campbell, David V. (Albuquerque, NM)

    1997-01-01T23:59:59.000Z

    Self-stressing test structures for realistic high frequency reliability characterizations. An on-chip high frequency oscillator, controlled by DC signals from off-chip, provides a range of high frequency pulses to test structures. The test structures provide information with regard to a variety of reliability failure mechanisms, including hot-carriers, electromigration, and oxide breakdown. The system is normally integrated at the wafer level to predict the failure mechanisms of the production integrated circuits on the same wafer.

  8. Improvement of SRAM-based failure analysis calibrated IDDQ testing

    E-Print Network [OSTI]

    Balachandran, Hariharan

    1996-01-01T23:59:59.000Z

    the methodology and detail procedure of simulation based failure analysis t, echnique is explained. Chapter IV discusses the implementation of Iddq current calibration. Chapter V provides some examples supporting the failure analysis methodology . Conclusion... method that is often used to localize surface defects is by examining the hot emission spots. This process functions by detecting the excessive heat generated by the defective neighborhood during device operation. Heat sensitive liquid crystal...

  9. E-Print Network 3.0 - assessment containment failure Sample Search...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Henning and Paasch 17 also adopt... A FUNCTION BASED DESIGN TOOL FOR FAILURE MODE IDENTIFICATION AND FAILURE-FREE DESIGN by SRIKESH G... ABSTRACT Knowledge of potential...

  10. Technology platform development for targeted plasma metabolites in human heart failure

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    statement from the American Heart Association. CirculationHospitalizations after heart failure diagnosis a communityof and survival with heart failure. N Eng J Med 2002, 347:

  11. Localization and activation of CaMKII delta isoforms and their involvement in heart failure

    E-Print Network [OSTI]

    Mishra, Shikha

    2010-01-01T23:59:59.000Z

    hypertrophy and heart failure ..CaMKII mediated hypertrophy and heart failure .. I.F.II.C. Preparation of heart tissue extract and cell lysate

  12. Integration of Failure Modes and Effects Analysis (FMEA) in the Engineering Design Process.

    E-Print Network [OSTI]

    Wen, Hua-wei

    2013-01-01T23:59:59.000Z

    ??ABSTRACT Integration of Failure Modes and Effects Analysis (FMEA) in the Engineering Design Process Hua-wei Wen Failure modes and effects analysis (FMEA) is one of… (more)

  13. Compression-induced failure of electro-active polymeric thin films

    E-Print Network [OSTI]

    Domenico De Tommasi; Giuseppe Puglisi; Giuseppe Zurlo

    2010-12-07T23:59:59.000Z

    The insurgence of compression induces wrinkling in actuation devices based on EAPs thin films leading to a sudden decrease of performances up to failure. Based on the classical tension field theory for thin elastic membranes, we provide a general framework for the analysis of the insurgence of in-plane compression in membranes of electroactive polymers (EAPs). Our main result is the deduction of a (voltage-dependent) domain in the stretch space which represents tensile configurations. Under the assumption of Mooney-Rivlin materials, we obtain that for growing values of the applied voltage the domain contracts, vanishing at a critical voltage above which the polymer is wrinkled for any stretch configuration. Our approach can be easily implemented in numerical simulations for more complex material behaviors and provides a tool for the analysis of compression instability as a function of the elastic moduli.

  14. MATERIALS MANAGEMENT MATERIALS MANAGEMENT -INVENTORY CONTROL

    E-Print Network [OSTI]

    Oliver, Douglas L.

    MATERIALS MANAGEMENT MATERIALS MANAGEMENT - INVENTORY CONTROL NOTICE OF DESIGNATED DEPARTMENTAL OF MATERIALS MANAGEMENT ______ FURTHER INSTRUCTIONS 1. Include a copy of any relevant documents. 2. Item MATERIALS COORDINATOR ­ IC-8 Mail, Fax or PDF the entire package to: MC 2010 Fax: 679-4240 REFERENCE # DMC

  15. Modeling and Simulating Blast Effects on Electric Substations

    SciTech Connect (OSTI)

    Lyle G. Roybal; Robert F. Jeffers; Kent E. McGillivary; Tony D. Paul; Ryan Jacobson

    2009-05-01T23:59:59.000Z

    A software simulation tool was developed at the Idaho National Laboratory to estimate the fragility of electric substation components subject to an explosive blast. Damage caused by explosively driven fragments on a generic electric substation was estimated by using a ray-tracing technique to track and tabulate fragment impacts and penetrations of substation components. This technique is based on methods used for assessing vulnerability of military aircraft and ground vehicles to explosive blasts. An open-source rendering and ray-trace engine was used for geometric modeling and interactions between fragments and substation components. Semi-empirical material interactions models were used to calculate blast parameters and simulate high-velocity material interactions between explosively driven fragments and substation components. Finally, a Monte Carlo simulation was added to model the random nature of fragment generation allowing a skilled analyst to predict failure probabilities of substation components.

  16. DUSTMS-D: DISPOSAL UNIT SOURCE TERM - MULTIPLE SPECIES - DISTRIBUTED FAILURE DATA INPUT GUIDE.

    SciTech Connect (OSTI)

    SULLIVAN, T.M.

    2006-01-01T23:59:59.000Z

    Performance assessment of a low-level waste (LLW) disposal facility begins with an estimation of the rate at which radionuclides migrate out of the facility (i.e., the source term). The focus of this work is to develop a methodology for calculating the source term. In general, the source term is influenced by the radionuclide inventory, the wasteforms and containers used to dispose of the inventory, and the physical processes that lead to release from the facility (fluid flow, container degradation, wasteform leaching, and radionuclide transport). Many of these physical processes are influenced by the design of the disposal facility (e.g., how the engineered barriers control infiltration of water). The complexity of the problem and the absence of appropriate data prevent development of an entirely mechanistic representation of radionuclide release from a disposal facility. Typically, a number of assumptions, based on knowledge of the disposal system, are used to simplify the problem. This has been done and the resulting models have been incorporated into the computer code DUST-MS (Disposal Unit Source Term-Multiple Species). The DUST-MS computer code is designed to model water flow, container degradation, release of contaminants from the wasteform to the contacting solution and transport through the subsurface media. Water flow through the facility over time is modeled using tabular input. Container degradation models include three types of failure rates: (a) instantaneous (all containers in a control volume fail at once), (b) uniformly distributed failures (containers fail at a linear rate between a specified starting and ending time), and (c) gaussian failure rates (containers fail at a rate determined by a mean failure time, standard deviation and gaussian distribution). Wasteform release models include four release mechanisms: (a) rinse with partitioning (inventory is released instantly upon container failure subject to equilibrium partitioning (sorption) with the waste form), (b) diffusion release.(release from either a cylindrical, spherical, or rectangular wasteform), (c) dissolution release (uniform release over time due to dissolution of the wasteform surface), and (d) solubility limited release. The predicated wasteform releases are corrected for radioactive decay and ingrowth. A unique set of container failure and wasteform release parameters can be specified for each control volume with a container. Contaminant transport is modeled through a finite-difference solution of the advective transport equation with sources (wasteform release and ingrowth) and radioactive decay. Although DUST-MS simulates one-dimensional transport, it can be used to simulate migration down to an aquifer and then transport in the aquifer by running the code twice. A special subroutine allows the flux into the aquifer from the first simulation to be input as the flux at the upstream boundary in the aquifer. This document presents the models used to calculate release from a disposal facility, verification of the model, and instructions on the use of the DUST-MS code. In addition to DUST-MS, a preprocessor, DUSTINMS, which helps the code user create input decks for DUST-MS and a post-processor, GRAFMS, which takes selected output files and plots them on the computer terminal have been written. Use of these codes is also described. In using DUST-MS, as with all computer models, the validity of the predictions relies heavily on the validity of the input parameters. Often, the largest uncertainties arise from uncertainty in the input parameters. Therefore, it is crucial to document and support the use of these parameters. The DUST-MS code, because of its flexibility and ability to compute release rates quickly, is extremely useful for screening to determine the radionuclide released at the highest rate, parameter sensitivity analysis and, with proper choice of the input parameters, provide upper bounds to release rates.

  17. Viscoelastic behavior of fiber-reinforced composite materials undergoing cure

    E-Print Network [OSTI]

    Wang, Kai

    1999-01-01T23:59:59.000Z

    A viscoelastic material model has been proposed to characterize the curing and thermal effects on the viscoelastic material properties of both the matrix material and the composite lamina. Micromechanics simulations are used to generate...

  18. ELSEVIER Journal of Nuclear Materials 212-215 (1994)1003-1009 An assessment of models for tritium release from ceramic

    E-Print Network [OSTI]

    Abdou, Mohamed

    1994-01-01T23:59:59.000Z

    release from ceramic breeders for blanket analysis applications G. Federici a, A.R. Raffray b, M proposed and used to analyse the tritium release from ceramic breeder blankets. The transient models range from single-mechanism types of models to comprehensive, fully integrated models over a blanket spatial

  19. Method for forming materials

    DOE Patents [OSTI]

    Tolle, Charles R. (Idaho Falls, ID); Clark, Denis E. (Idaho Falls, ID); Smartt, Herschel B. (Idaho Falls, ID); Miller, Karen S. (Idaho Falls, ID)

    2009-10-06T23:59:59.000Z

    A material-forming tool and a method for forming a material are described including a shank portion; a shoulder portion that releasably engages the shank portion; a pin that releasably engages the shoulder portion, wherein the pin defines a passageway; and a source of a material coupled in material flowing relation relative to the pin and wherein the material-forming tool is utilized in methodology that includes providing a first material; providing a second material, and placing the second material into contact with the first material; and locally plastically deforming the first material with the material-forming tool so as mix the first material and second material together to form a resulting material having characteristics different from the respective first and second materials.

  20. EVALUATION OF THE FAILURE OF A RADIOACTIVE WASTE TRANSFER LINE JACKET

    SciTech Connect (OSTI)

    Wiersma, B; Alan03 Plummer, A; Karthik Subramanian, K; Charles Jenkins, C; William Hinz, W; A Fellinger, A

    2007-04-06T23:59:59.000Z

    Radioactive wastes are confined in 49 underground storage tanks at the Savannah River Site. The waste is transported between tanks primarily via an underground transfer piping system. Due to the hazardous nature of the waste, the inner core stainless steel pipe is typically surrounded by a carbon steel pipe jacket, which provides secondary containment. Recently several through-wall penetrations were discovered on a segment of one of the jackets. An evaluation was performed to verify the failure mechanism and to estimate the degree of damage that occurred to the pipe segment. Failure analysis of a section of the jacket confirmed that pitting corrosion on the exterior of the pipe led to the through-wall penetration. Ultrasonic measurements on sections of the pipe were utilized to determine the remaining wall thickness in adjacent areas of the pipe. Based on these measurements, the degree of pitting and general corrosion was determined. Pit growth rate models were then developed to estimate the life expectancy of sections of the pipe that had not been excavated. The calculations estimated that the occurrence of through-wall failures in this jacket will begin to increase substantially in 12 years. Given that this pipe segment will be utilized beyond this time, short-term and long-term solutions to this failure were proposed. The short-term solutions focused on the repair or replace decisions that must be made to return the jacket to service as soon as practical. The long-term solutions focused on a broader strategy to address jacket integrity issues in the entire tank farm facility. These solutions included the evaluation of innovative remote inspection and repair techniques.