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American perspectives on security : energy, environment, nuclear weapons, and terrorism : 2010

Herron, Kerry G.; Jenkins-Smith, Hank C.; Silva, Carol L.

We report findings from an Internet survey and a subset of questions administered by telephone among the American public in mid-2010 on US energy and environmental security. Key areas of investigation include public perceptions shaping the context for debate about a comprehensive national energy policy, and what levels of importance are assigned to various prospective energy technologies. Additionally, we investigate how public views on global climate change are evolving, how the public assesses the risks and benefits of nuclear energy, preferences for managing used nuclear fuel, and public trust in sources of scientific and technical information. We also report findings from a national Internet survey and a subset of questions administered by telephone in mid-2010 on public views of the relevance of US nuclear weapons today, support for strategic arms control, and assessments of the potential for nuclear abolition. Additionally, we analyze evolving public views of the threat of terrorism, assessments of progress in the struggle against terrorism, and tolerance for intrusive antiterror policies. Where possible, findings from each survey are compared with previous surveys in this series for analyses of trends.

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TYPE SAND Report YEAR 2011
DOIOSTI

Adagio 4.20 User’s Guide

Spencer, Benjamin W.

Adagio is a Lagrangian, three-dimensional, implicit code for the analysis of solids and structures. It uses a multi-level iterative solver, which enables it to solve problems with large deformations, nonlinear material behavior, and contact. It also has a versatile library of continuum and structural elements, and an extensive library of material models. Adagio is written for parallel computing environments, and its solvers allow for scalable solutions of very large problems. Adagio uses the SIERRA Framework, which allows for coupling with other SIERRA mechanics codes. This document describes the functionality and input structure for Adagio.

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TYPE SAND Report YEAR 2011
DOIOSTI

Nuclear Energy Advanced Modeling and Simulation (NEAMS) waste Integrated Performance and Safety Codes (IPSC) : gap analysis for high fidelity and performance assessment code development

Wang, Yifeng

This report describes a gap analysis performed in the process of developing the Waste Integrated Performance and Safety Codes (IPSC) in support of the U.S. Department of Energy (DOE) Office of Nuclear Energy Advanced Modeling and Simulation (NEAMS) Campaign. The goal of the Waste IPSC is to develop an integrated suite of computational modeling and simulation capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive waste storage or disposal system. The Waste IPSC will provide this simulation capability (1) for a range of disposal concepts, waste form types, engineered repository designs, and geologic settings, (2) for a range of time scales and distances, (3) with appropriate consideration of the inherent uncertainties, and (4) in accordance with rigorous verification, validation, and software quality requirements. The gap analyses documented in this report were are performed during an initial gap analysis to identify candidate codes and tools to support the development and integration of the Waste IPSC, and during follow-on activities that delved into more detailed assessments of the various codes that were acquired, studied, and tested. The current Waste IPSC strategy is to acquire and integrate the necessary Waste IPSC capabilities wherever feasible, and develop only those capabilities that cannot be acquired or suitably integrated, verified, or validated. The gap analysis indicates that significant capabilities may already exist in the existing THC codes although there is no single code able to fully account for all physical and chemical processes involved in a waste disposal system. Large gaps exist in modeling chemical processes and their couplings with other processes. The coupling of chemical processes with flow transport and mechanical deformation remains challenging. The data for extreme environments (e.g., for elevated temperature and high ionic strength media) that are needed for repository modeling are severely lacking. In addition, most of existing reactive transport codes were developed for non-radioactive contaminants, and they need to be adapted to account for radionuclide decay and in-growth. The accessibility to the source codes is generally limited. Because the problems of interest for the Waste IPSC are likely to result in relatively large computational models, a compact memory-usage footprint and a fast/robust solution procedure will be needed. A robust massively parallel processing (MPP) capability will also be required to provide reasonable turnaround times on the analyses that will be performed with the code. A performance assessment (PA) calculation for a waste disposal system generally requires a large number (hundreds to thousands) of model simulations to quantify the effect of model parameter uncertainties on the predicted repository performance. A set of codes for a PA calculation must be sufficiently robust and fast in terms of code execution. A PA system as a whole must be able to provide multiple alternative models for a specific set of physical/chemical processes, so that the users can choose various levels of modeling complexity based on their modeling needs. This requires PA codes, preferably, to be highly modularized. Most of the existing codes have difficulties meeting these requirements. Based on the gap analysis results, we have made the following recommendations for the code selection and code development for the NEAMS waste IPSC: (1) build fully coupled high-fidelity THCMBR codes using the existing SIERRA codes (e.g., ARIA and ADAGIO) and platform, (2) use DAKOTA to build an enhanced performance assessment system (EPAS), and build a modular code architecture and key code modules for performance assessments. The key chemical calculation modules will be built by expanding the existing CANTERA capabilities as well as by extracting useful components from other existing codes.

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TYPE SAND Report YEAR 2011
DOIOSTI

Making tensor factorizations robust to non-gaussian noise

Kolda, Tamara G.

Tensors are multi-way arrays, and the CANDECOMP/PARAFAC (CP) tensor factorization has found application in many different domains. The CP model is typically fit using a least squares objective function, which is a maximum likelihood estimate under the assumption of independent and identically distributed (i.i.d.) Gaussian noise. We demonstrate that this loss function can be highly sensitive to non-Gaussian noise. Therefore, we propose a loss function based on the 1-norm because it can accommodate both Gaussian and grossly non-Gaussian perturbations. We also present an alternating majorization-minimization (MM) algorithm for fitting a CP model using our proposed loss function (CPAL1) and compare its performance to the workhorse algorithm for fitting CP models, CP alternating least squares (CPALS).

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TYPE SAND Report YEAR 2011
DOIOSTI

Laser wafering for silicon solar

Sweatt, W.C.; Jared, Bradley H.

Current technology cuts solar Si wafers by a wire saw process, resulting in 50% 'kerf' loss when machining silicon from a boule or brick into a wafer. We want to develop a kerf-free laser wafering technology that promises to eliminate such wasteful wire saw processes and achieve up to a ten-fold decrease in the g/W{sub p} (grams/peak watt) polysilicon usage from the starting polysilicon material. Compared to today's technology, this will also reduce costs ({approx}20%), embodied energy, and green-house gas GHG emissions ({approx}50%). We will use short pulse laser illumination sharply focused by a solid immersion lens to produce subsurface damage in silicon such that wafers can be mechanically cleaved from a boule or brick. For this concept to succeed, we will need to develop optics, lasers, cleaving, and high throughput processing technologies capable of producing wafers with thicknesses < 50 {micro}m with high throughput (< 10 sec./wafer). Wafer thickness scaling is the 'Moore's Law' of silicon solar. Our concept will allow solar manufacturers to skip entire generations of scaling and achieve grid parity with commercial electricity rates. Yet, this idea is largely untested and a simple demonstration is needed to provide credibility for a larger scale research and development program. The purpose of this project is to lay the groundwork to demonstrate the feasibility of laser wafering. First, to design and procure on optic train suitable for producing subsurface damage in silicon with the required damage and stress profile to promote lateral cleavage of silicon. Second, to use an existing laser to produce subsurface damage in silicon, and third, to characterize the damage using scanning electron microscopy and confocal Raman spectroscopy mapping.

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TYPE SAND Report YEAR 2011
DOIOSTI

Sandia National Laboratories, California Environmental Monitoring Program annual report for 2011

Holland, Robert C.

The annual program report provides detailed information about all aspects of the SNL/California Environmental Monitoring Program. It functions as supporting documentation to the SNL/California Environmental Management System Program Manual. The 2010 program report describes the activities undertaken during the previous year, and activities planned in future years to implement the Environmental Monitoring Program, one of six programs that supports environmental management at SNL/California.

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TYPE SAND Report YEAR 2011
DOIOSTI

A theory manual for multi-physics code coupling in LIME

Bartlett, Roscoe; Belcourt, Kenneth; Hooper, Russell; Schmidt, Rodney C.

The Lightweight Integrating Multi-physics Environment (LIME) is a software package for creating multi-physics simulation codes. Its primary application space is when computer codes are currently available to solve different parts of a multi-physics problem and now need to be coupled with other such codes. In this report we define a common domain language for discussing multi-physics coupling and describe the basic theory associated with multiphysics coupling algorithms that are to be supported in LIME. We provide an assessment of coupling techniques for both steady-state and time dependent coupled systems. Example couplings are also demonstrated.

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TYPE SAND Report YEAR 2011
DOIOSTI

Harsh environments electronics : downhole applications

Vianco, Paul T.

The development and operational sustainment of renewable (geothermal) and non-renewable (fossil fuel) energy resources will be accompanied by increasingly higher costs factors: exploration and site preparation, operational maintenance and repair. Increased government oversight in the wake of the Gulf oil spill will only add to the cost burden. It is important to understand that downhole conditions are not just about elevated temperatures. It is often construed that military electronics are exposed to the upper limit in terms of extreme service environments. Probably the harshest of all service conditions for electronics and electrical equipment are those in oil, gas, and geothermal wells. From the technology perspective, advanced materials, sensors, and microelectronics devices are benefificial to the exploration and sustainment of energy resources, especially in terms of lower costs. Besides the need for the science that creates these breakthroughs - there is also a need for sustained engineering development and testing. Downhole oil, gas, and geothermal well applications can have a wide range of environments and reliability requirements: Temperature, Pressure, Vibration, Corrosion, and Service duration. All too frequently, these conditions are not well-defifined because the application is labeled as 'high temperature'. This ambiguity is problematic when the investigation turns to new approaches for electronic packaging solutions. The objective is to develop harsh environment, electronic packaging that meets customer requirements of cost, performance, and reliability. There are a number of challenges: (1) Materials sets - solder alloys, substrate materials; (2) Manufacturing process - low to middle volumes, low defect counts, new equipment technologies; and (3) Reliability testing - requirements documents, test methods and modeling, relevant standards documents. The cost to develop and sustain renewable and non-renewable energy resources will continue to escalate within the industry. Downhole electronics can provide a very cost-effective approach for well exploration and sustainment (data logging). However, the harsh environments are a 'game-changer' in terms defining materials, assembly processes and the long-term reliability of downhole electronic systems. The system-level approach will enable the integration of each of these contributors - materials, processes, and reliability - in order to deliver cost-effective electronics that meet customer requirements.

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TYPE Conference YEAR 2011
OSTI

Software enhancements to the IVSEM model of the CTBTO IMS

Damico, Joseph P.

Sandia National Laboratories (SNL) developed the Integrated Verification System Evaluation Model (IVSEM) to estimate the performance of the International Monitoring System (IMS) operated by the Comprehensive Nuclear Test Ban Treaty Organization (CTBTO). IVSEM was developed in several phases between 1995 and 2000. The model was developed in FORTRAN with an IDL-based user interface and was compiled for Windows and UNIX operating systems. Continuing interest in this analysis capability, coupled with numerous advances in desktop computer hardware and software since IVSEM was written, enabled significant improvements to IVSEM run-time performance and data analysis capabilities. These improvements were implemented externally without modifying the FORTRAN executables, which had been previously verified. This paper describes the parallelization approach developed to significantly reduce IVSEM run-times and the new test setup and analysis tools developed to facilitate better IVSEM operation.

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TYPE SAND Report YEAR 2011
DOIOSTI

Hydrocarbon characterization experiments in fully turbulent fires : results and data analysis

Blanchat, Thomas K.; Suo-Anttila, Jill M.

As the capabilities of numerical simulations increase, decision makers are increasingly relying upon simulations rather than experiments to assess risks across a wide variety of accident scenarios including fires. There are still, however, many aspects of fires that are either not well understood or are difficult to treat from first principles due to the computational expense. For a simulation to be truly predictive and to provide decision makers with information which can be reliably used for risk assessment the remaining physical processes must be studied and suitable models developed for the effects of the physics. The model for the fuel evaporation rate in a liquid fuel pool fire is significant because in well-ventilated fires the evaporation rate largely controls the total heat release rate from the fire. This report describes a set of fuel regression rates experiments to provide data for the development and validation of models. The experiments were performed with fires in the fully turbulent scale range (> 1 m diameter) and with a number of hydrocarbon fuels ranging from lightly sooting to heavily sooting. The importance of spectral absorption in the liquid fuels and the vapor dome above the pool was investigated and the total heat flux to the pool surface was measured. The importance of convection within the liquid fuel was assessed by restricting large scale liquid motion in some tests. These data sets provide a sound, experimentally proven basis for assessing how much of the liquid fuel needs to be modeled to enable a predictive simulation of a fuel fire given the couplings between evaporation of fuel from the pool and the heat release from the fire which drives the evaporation.

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TYPE SAND Report YEAR 2011
DOIOSTI

Two dimensional point of use fuel cell : a final LDRD project report

Zavadil, Kevin R.

The Proliferation Assessment (program area - Things Thin) within the Defense Systems and Assessment Investment Area desires high energy density and long-lived power sources with moderate currents (mA) that can be used as building blocks in platforms for the continuous monitoring of chemical, biological, and radiological agents. Fuel cells can be an optimum choice for a power source because of the high energy densities that are possible with liquid fuels. Additionally, power generation and fuel storage can be decoupled in a fuel cell for independent control of energy and power density for customized, application-driven power solutions. Direct methanol fuel cells (DMFC) are explored as a possible concept to develop into ultrathin or two-dimensional power sources. New developments in nanotechnology, advanced fabrication techniques, and materials science are exploited to create a planar DMFC that could be co-located with electronics in a chip format. Carbon nanotubes and pyrolyzed polymers are used as building block electrodes - porous, mechanically compliant current collectors. Directed assembly methods including surface functionalization and layer-by-layer deposition with polyelectrolytes are used to pattern, build, and add functionality to these electrodes. These same techniques are used to incorporate nanoscale selective electrocatalyst into the carbon electrodes to provide a high density of active electron transfer sites for the methanol oxidation and oxygen reduction reactions. The resulting electrodes are characterized in terms of their physical properties, electrocatalytic function, and selectivity to better understand how processing impacts their performance attributes. The basic function of a membrane electrode assembly is demonstrated for several prototype devices.

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TYPE SAND Report YEAR 2011
DOIOSTI
Results 69601–69800 of 99,299
Results 69601–69800 of 99,299