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Feasibility Study on Fire Suppression Properties of the Sandia Decon Foam

Williams, Cecelia V.

A non-toxic, non-corrosive aqueous foam with enhanced physical stability for the rapid mitigation and decontamination of CBW agents has been developed at Sandia. This technology is attractive for the protection of the Nuclear Weapons facilities as well as for civilian and military applications for several reasons including (1) it requires minimal logistics support, (2) a single decon solution can be used for both CW and BW agents, (3) mitigation of agents can be accomplished in bulk, aerosol, and vapor phases, (4) it can be deployed rapidly, (5) it exhibits minimal health and collateral damage, (6) it is relatively inexpensive, and (7) it has minimal run-off of fluids and no lasting environmental impact. A range of methods including systems that yield desirable properties for fire suppression foams can deliver the foam. Although the foam's effectiveness against CBW agents is well established, the additional capability of being used for fire suppression would provide a dual-use capability. If the foam can suppress and control fires, it could lead to a significant enhancement to the level of protection for critical nuclear weapon facilities in that existing foam-based fire suppression systems could now provide the additional protection of decontamination and CBW agent removal. Fire suppression properties of the foam were investigated with the assistance of Southwest Research Institute Department of Fire Technology in conjunction with EnviroFoam Technologies, Inc., a technology licensee.

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Parametric Study for Large Wind Turbine Blades: WindPACT Blade System Design Studies

Ashwill, Thomas D.

This report presents the results of a study of various wind turbine blade design parameters as a function of blade length in the range from 30 meters to 70 meters. The results have been summarized in dimensional and non-dimensional formats to aid in interpretation. The parametric review estimated peak power and annual energy capture for megawatt scale wind turbines with rotors of 62, 83, 104, 125, and 146 meters in diameter. The baseline ''thin'' distribution represents conventional airfoils used in large wind turbine blades. The ''thicker'' and ''thickest'' distributions utilize airfoils that have significantly increased thickness to improve structural performance and reduce weight. An aerodynamic scaling effort was undertaken in parallel with the structural analysis work to evaluate the effect of extreme thickness on aerodynamic characteristics. Increased airfoil section thickness appears to be a key tool in limiting blade weight and cost growth with scale. Thickened and truncated trailing edges in the inboard region provide strong, positive effects on blade structural performance. Larger blades may require higher tip speeds combined with reduced blade solidity to limit growth of design loads. A slender blade can be used to reduce extreme design loads when the rotor is parked, but requires a higher tip speed.

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Strategies for the War on Terrorism: Results of a Special Study

Moore, Judy H.

On September 13, 2001, the first day after the attacks of September 11 that Sandia National Laboratories re-opened, Vice President Gerry Yonas entirely redirected the efforts of his organization, the Advanced Concepts Group (ACG), to the problem of terrorism. For the next several weeks, the ACG focused on trying to better characterize the international terrorist threat and the vulnerabilities of the US to further attacks. This work culminated in a presentation by Dr . Yonas to the Fall Leadership Focus meeting at Sandia National Laboratories on October 22. Following that meeting, President and Lab Director, Paul Robinson, asked Dr. Yonas and the ACG to develop a long-term (3-5 year) technology roadmap showing how Sandia could direct efforts to making major contributions to the success of the nation's war on terrorism. The ACG effort would communicate with other Labs activities working on near-term responses to Federal calls for technological support. The ACG study was conducted in two phases. The first, more exploratory, stage divided the terrorism challenge into three broad parts, each examined by a team that included both permanent ACG staff and part-time staff and consultants from other Sandia organizations. The ''Red'' team looked at the problems of finding and stopping terrorists before they strike (or strike again). The ''Yellow'' team studied the problems of protecting people and facilities from terrorist attacks, as well as those of responding to attacks that occur. The ''Green'' team attempted to understand the long-term, ''root'' causes of terrorism, and how technology might help ameliorate the conditions that lead people to support, or even become, terrorists. In addition, a ''Purple'' team worked with the other teams to provide an integrating vision for them all, to help make appropriate connections among them, and to see that they left no important gaps between them. The findings of these teams were presented to a broad representation of laboratory staff and management on January 3, 2002. From the many ideas explored by the Red, Green, and Yellow teams, and keeping in mind criteria formulated by the Purple team, the ACG assembled a set of five major technology development goals. These goals, if pursued, could lead to major contributions to the war on terrorism. With some rearrangement of team members and coordinators, a new set of teams began fleshing out these five ''Big Hairy Audacious Goals'' for the consideration of Laboratory leadership. Dr. Yonas briefed Sandia upper management on the work of these teams on February 4, 2002. This report presents the essence of that work as applicable to the R&D community of the nation interested in the development of better tools for a long term ''War on Terrorism.''

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Robust Planning for Autonomous Navigation of Mobile Robots in Unstructured, Dynamic Environments: An LDRD Final Report

Eisler, G.R.

This report summarizes the analytical and experimental efforts for the Laboratory Directed Research and Development (LDRD) project entitled ''Robust Planning for Autonomous Navigation of Mobile Robots In Unstructured, Dynamic Environments (AutoNav)''. The project goal was to develop an algorithmic-driven, multi-spectral approach to point-to-point navigation characterized by: segmented on-board trajectory planning, self-contained operation without human support for mission duration, and the development of appropriate sensors and algorithms to navigate unattended. The project was partially successful in achieving gains in sensing, path planning, navigation, and guidance. One of three experimental platforms, the Minimalist Autonomous Testbed, used a repetitive sense-and-re-plan combination to demonstrate the majority of elements necessary for autonomous navigation. However, a critical goal for overall success in arbitrary terrain, that of developing a sensor that is able to distinguish true obstacles that need to be avoided as a function of vehicle scale, still needs substantial research to bring to fruition.

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Three-Dimensional Wind Field Modeling: A Review

Homicz, Gregory F.

Over the past several decades, the development of computer models to predict the atmospheric transport of hazardous material across a local (on the order of 10s of km) to mesoscale (on the order of 100s of km) region has received considerable attention, for both regulatory purposes, and to guide emergency response teams. Wind inputs to these models cover a spectrum of sophistication and required resources. At one end is the interpolation/extrapolation of available observations, which can be done rapidly, but at the risk of missing important local phenomena. Such a model can also only describe the wind at the time the observations were made. At the other end are sophisticated numerical solutions based on so-called Primitive Equation models. These prognostic models, so-called because in principle they can forecast future conditions, contain the most physics, but can easily consume tens of hours, if not days, of computer time. They may also require orders of magnitude more effort to set up, as both boundary and initial conditions on all the relevant variables must be supplied. The subject of this report is two classes of models intermediate in sophistication between the interpolated and prognostic ends of the spectrum. The first, known as mass-consistent (sometimes referred to as diagnostic) models, attempt to strike a compromise between simple interpolation and the complexity of the Primitive Equation models by satisfying only the conservation of mass (continuity) equation. The second class considered here consists of the so-called linear models, which purport to satisfy both mass and momentum balances. A review of the published literature on these models over the past few decades was performed. Though diagnostic models use a variety of approaches, they tend to fall into a relatively few well-defined categories. Linear models, on the other hand, follow a more uniform methodology, though they differ in detail. The discussion considers the theoretical underpinnings of each category of the diagnostic models, and the linear models, in order to assess the advantages and disadvantages of each. It is concluded that diagnostic models are the better suited of the two for predicting the atmospheric dispersion of hazardous materials in emergency response scenarios, as the linear models are only able to accommodate gently-sloping terrain, and are predicated on several simplifying approximations which can be difficult to justify a priori. Of the various approaches used in diagnostic modeling, that based on the calculus of variations appears to be the most objective, in that it introduces the fewest number of arbitrary parameters. The strengths and weaknesses of models in this category, as they relate to the activities of Sandia's Nuclear Emergency Support Team (NEST), are further highlighted.

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2002 Biological Assessment For Continued Operation of Sandia National Laboratories, California

Baker, Alexandra M.; Manger, Trevor J.

The purpose of this biological assessment is to review the proposed continued operation of Sandia National Laboratories, California (SNL/CA) in sufficient detail to determine to what extent the proposed action may affect the species listed below. This assessment is prepared in accordance with Section 7 of the Endangered Species Act [16 U.S.C. 1536 (c)].

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Kernel Near Principal Component Analysis

Martin, Shawn

We propose a novel algorithm based on Principal Component Analysis (PCA). First, we present an interesting approximation of PCA using Gram-Schmidt orthonormalization. Next, we combine our approximation with the kernel functions from Support Vector Machines (SVMs) to provide a nonlinear generalization of PCA. After benchmarking our algorithm in the linear case, we explore its use in both the linear and nonlinear cases. We include applications to face data analysis, handwritten digit recognition, and fluid flow.

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Occurrence, Characterization and Synthesis of Hanford and SRS Tank Heel Materials

Krumhansl, James L.

The long-range objective of this study was to develop chemically assisted technologies for removing heels from tanks. In FY 01, the first two steps toward this objective were taken: (1) catalogue the occurrence and nature of tank heels and assess which materials are available for study and (2) develop methods for synthesizing non-radioactive surrogate heel materials for use in testing potential removal technologies. The chief finding of Task 1 was the existence of ''heels'', depending on the definition used. Hard materials that would be almost impossible to remove by sluicing are all but absent from the records of both Savannah River and Hanford. Historical usage suggests that the term ''heel'' may also apply to chunky, granular, or semi-solid pasty accumulations. These materials are documented and may also be difficult to remove by conventional sluicing technologies. Such heels may be comprised of normal sludge components, dominantly iron and aluminum hydroxides, or they may result from added materials which were not part of the normal fuel reprocessing operations: Portland cement, diatomaceous earth, sand and soil and spent zeolite ion exchange ''resins''. The occurrence and chemistry of the most notable ''heel'', that of the zeolite mass in Tank 19F at Savannah River, is reviewed in some detail. Secondly, no clear correlation was found between high tank temperatures and difficulties encountered in removing materials from a tank at a later date; nor did the sludges from these tanks give any indication of being particularly solid. Experimental studies to develop synthetic heel materials were caned out using a number of different approaches. For normal sludge materials settling, even when assisted by a centrifuge, it proved ineffective. The same result was obtained from drying sludge samples. Even exposing sludges to a molten salt melt at 233 C, only produced a fine powder, rather than a resilient ceramic which resisted disaggregation. A cohesive material, however, was produced by wicking the pore fluid out of a sludge gel (into packed diatomaceous earth), while simultaneously applying pressure to compact the sludge as it dehydrated. Osmotic gradients could provide the same function as the capillary forces provided by the diatomaceous earth sorbant placed in contact with the sludge. Tests on the anomalous materials added to the tanks all indicated potential problems. Hard granules, and maybe chunks, may be encountered where Portland cement was added to a tank. Sand, spent zeolite resin, and diatomaceous earth, will all react with the tank fluids to produce a sodalite/cancrinite material. The degree of reaction determines whether the grains become cemented together. SRS activities showed that heels formed when spent zeolites were added to tanks can be readily dislodged and it is expected that heels from sand would possess equal or less cohesion. Diatomaceous earth may form more resilient crusts or masses. To summarize, the existence of ''hard'' heels has yet to be documented. A broader definition suggests inclusion of poorly cohesive cancrinite-cemented masses and dense past-like accumulations of abnormally compacted ''normal'' sludges. Chemical treatments to remove these materials must focus on agents that are active against aluminosilicates and hydrous oxides of iron and aluminum. Exploiting the high pore-water content of these materials may provide a second avenue for dislodging such accumulations. Techniques were developed to produce synthetic sludges on which various removal technologies could be tried.

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Blade System Design Studies Volume I: Composite Technologies for Large Wind Turbine Blades

Ashwill, Thomas D.

As part of the U.S. Department of Energy's Wind Partnerships for Advanced Component Technologies (WindPACT) program, Global Energy Concepts LLC (GEC) is performing a study concerning innovations in materials, processes and structural configurations for application to wind turbine blades in the multi-megawatt range. The project team for this work includes experts in all areas of wind turbine blade design, analysis, manufacture, and testing. Constraints to cost-effective scaling-up of the current commercial blade designs and manufacturing methods are identified, including self-gravity loads, transportation, and environmental considerations. A trade-off study is performed to evaluate the incremental changes in blade cost, weight, and stiffness for a wide range of composite materials, fabric types, and manufacturing processes. Fiberglass/carbon fiber hybrid blades are identified as having a promising combination of cost, weight, stiffness and fatigue resistance. Vacuum-assisted resin transfer molding, resin film infision, and pre-impregnated materials are identified as having benefits in reduced volatile emissions, higher fiber content, and improved laminate quality relative to the baseline wet lay-up process. Alternative structural designs are identified, including jointed configurations to facilitate transportation. Based on the results to date, recommendations are made for further evaluation and testing under this study to verify the predicted material and structural performance.

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Viability of Applying Curie Point Pyrolysis/Gas Chromatography Techniques for Characterization of Ammonium Perchlorate Based Propellants

Barnett, James; Montoya, Bertha M.

Curie Point pyrolysis-gas chromatography was investigated for use as a tool for characterization of aged ammonium perchlorate based composite propellants (1). Successful application of the technique will support the surveillance program for the Explosives Materials and Subsystems Department (1). Propellant samples were prepared by separating the propellant into reacted (oxidated) and unreacted zones. The experimental design included the determination of system reliability followed by, reproducibility, sample preparation and analysis of pyrolysis products. Polystyrene was used to verify the reliability of the system and showed good reproducibility. Application of the technique showed high variation in the data. Modifications to sample preparation did not enhance the reproducibility. It was determined that the high concentration of ammonium perchlorate in the propellant matrix was compromising the repeatability of the analysis.

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WIPP Case Study - Compliance Monitoring, Passive Institutional Controls, and Record Keeping

Wagner, Stephen W.; Beauheim, Richard L.; Pfeifle, Thomas W.; Duran, Grace A.; Williams, Cecelia V.

The WIPP Case Study describes the compliance monitoring program, record keeping requirements, and passive institutional controls that are used to help ensure the Waste Isolation Pilot Plant (WIPP) will safety contain radioactive waste and indicate dangers and location of the wastes. The radioactive components in the waste are regulated by the U.S. Environmental Protection Agency (EPA) while the hazardous components in the waste are regulated by the New Mexico Environment Department (NMED). This paper addresses monitoring relating to radionuclide containment performance, passive institutional controls, and record keeping over a 10,000-year time frame. Monitoring relating to the hazardous components and the associated regulator are not addressed in this paper. The WIPP containment performance is mandated by release limits set by regulation. Regulations also require the radioactive waste containment performance of the WIPP to be predicted by a ''Performance Assessment.'' The EPA did not base the acceptance of the WIPP solely on predicted containment but included additional assurance measures. One such assurance measure is monitoring, which may be defined as the on-going measurement of conditions in and around the repository. This case study describes the evolution of the WIPP monitoring program as the WIPP project progressed through the planning, site characterization, regulatory promulgation, and eventual operational stages that spanned a period of over 25 years. Included are discussions of the regulatory requirements for monitoring, selection of monitoring parameters, trigger values used to identify unexpected conditions, assessment of monitoring data against the trigger values, and plans for post-closure monitoring. The United EPA established the requirements for Passive Institutional Controls (PICs) for disposal sites. The requirements state the a disposal site must be designated by the most permanent markers, records, and other passive institutional controls practicable to indicate the dangers of the wastes and their location. The PIC Task Force assessed the effectiveness of PICs in deterring inadvertent human intrusion and developed a conceptual design for permanently marking the Waste Isolation Pilot Plant (WIPP), establishing records, and identifying other practicable controls to indicate the dangers of the wastes and their location. The marking system should provide information regarding the location, design, contents, and hazards associated with WIPP. This paper discuss these controls including markers, records, archives, and government ownership and land-use restrictions.

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Device Technology Investigation: Subsystems Packaging Study: Feasibility of PCSS - Based Pulser for Highly Portable Platforms

Mar, Alan; Bacon, Larry D.; Loubriel, Guillermo M.

This report summarizes an investigation of the use of high-gain Photo-Conductive Semiconductor Switch (PCSS) technology for a deployable impulse source. This includes a discussion of viability, packaging, and antennas. High gain GaAs PCSS-based designs offer potential advantages in terms of compactness, repetition rate, and cost.

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Acoustic Wave Equations for a Linear Viscous Fluid and An Ideal Fluid

Aldridge, David F.

The mathematical description of acoustic wave propagation within a time- and space-varying, and moving, linear viscous fluid is formulated as a system of coupled linear equations. This system is rigorously developed from fundamental principles of continuum mechanics (conservation of mass, balance of linear and angular momentum, balance of entropy) and various constitutive relations (for stress, entropy production, and entropy conduction) by linearizing all expressions with respect to the small-amplitude acoustic wavefield variables. A significant simplification arises if the fluid medium is neither viscous nor heat conducting (i.e., an ideal fluid). In this case the mathematical system can be reduced to a set of five, coupled, first-order partial differential equations. Coefficients in the systems depend on various mechanical and thermodynamic properties of the ambient medium that supports acoustic wave propagation. These material properties cannot all be arbitrarily specified, but must satisfy another system of nonlinear expressions characterizing the dynamic behavior of the background medium. Dramatic simplifications in both systems occur if the ambient medium is simultaneously adiabatic and stationary.

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Evaluation of a Prototype Continuous-Wave, Borehole, Ground-Penetrating Radar

Weiss, Chester J.; Caffey, Thurlow W.H.

Borehole radar systems can provide essential subsurface structural information for environmental evaluation, geotechnical analysis, or energy exploration. Sandia developed a prototype continuous-wave Borehole Radar (BHR) in 1996, and development of a practical tool has been continuing at a Russian institute under a Sandia contract. The BHR field experiments, which were planned for the summer of 2001 in Russia, provided a unique opportunity to evaluate the latest Sandia algorithms with actual field data. A new three-dimensional code was developed to enable the analysis of BHR data on modest-sized desktop workstations. The code is based on the staggered grid, finite difference technique, and eliminates 55% of the massive storage associated with solving the system of finite-difference linear equations. The code was used to forward-model the Russian site geometry and placement of artificial targets to anticipate any problems that might arise when the data was received. Technical software and equipment problems in the Russian field tests, conducted in August 2001, invalidated all but one of the data sets. However, more field tests with improved equipment and software are planned for 2002, and analysis of that data will be presented in a future report.

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Salt Mechanics Primer for Near-Salt and Sub-Salt Deepwater Gulf of Mexico Field Developments

Fossum, Arlo F.; Fredrich, Joanne T.

The Gulf of Mexico (GoM) is the most active deepwater region in the world and provides some of the greatest challenges in scope and opportunity for the oil and gas industry. The complex geologic settings and significant water and reservoir depths necessitate high development costs, in addition to requiring innovating technology. The investment costs are substantial: because of the extreme water depths (up to 8000 feet) and considerable reservoir depths (to 30,000 feet below mudline), the cost of drilling a single well can be upwards of 50 to 100 million dollars. Central, therefore, to successful economic exploitation are developments with a minimum number of wells combined with a well service lifetime of twenty to thirty years. Many of the wells that are planned for the most significant developments will penetrate thick salt formations, and the combined drilling costs for these fields are estimated in the tens of billions of dollars. In May 2001, Sandia National Laboratories initiated a Joint Industry Project focused on the identification, quantification, and mitigation of potential well integrity issues associated with sub-salt and near-salt deepwater GoM reservoirs. The project is jointly funded by the DOE (Natural Gas and Oil Technology Partnership) and nine oil companies (BHP Billiton Petroleum, BP, ChevronTexaco, Conoco, ExxonMobil, Halliburton, Kerr-McGee, Phillips Petroleum, and Shell). This report provides an assessment of the state of the art of salt mechanics, and identifies potential well integrity issues relevant to deepwater GoM field developments. Salt deformation is discussed and a deformation mechanism map is provided for salt. A bounding steady-state strain rate contour map is constructed for deepwater GoM field developments, and the critical issue of constraint in the subsurface, and resultant necessity for numerical analyses is discussed.

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2002 SNL ASCI Applications Software Engineering Assessment Report

Williamson, Charles M.; Ogden, Harvey C.; Byle, Kathleen A.

This document describes the 2002 SNL Accelerated Strategic Computing Initiative (ASCI) Applications Software Quality Engineering (SQE) Assessment and the assessment results. The primary purpose of the assessment was to establish the current state of software engineering practices within the SNL ASCI Applications Program.

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Chem-Prep PZT 95/5 for Neutron Generator Applications: Particle Size Distribution Comparison of Development and Production-Scale Powders

Sipola, Diana L.; Voigt, James A.; Lockwood, Steven J.; Wright, Emily D.

The Materials Chemistry Department 1846 has developed a lab-scale chem-prep process for the synthesis of PNZT 95/5, a ferroelectric material that is used in neutron generator power supplies. This process (Sandia Process, or SP) has been successfully transferred to and scaled by Department 14192 (Ceramics and Glass Department), (Transferred Sandia Process, or TSP), to meet the future supply needs of Sandia for its neutron generator production responsibilities. In going from the development-size SP batch (1.6 kg/batch) to the production-scale TSP powder batch size (10 kg/batch), it was important that it be determined if the scaling process caused any ''performance-critical'' changes in the PNZT 95/5 being produced. One area where a difference was found was in the particle size distributions of the calcined PNZT powders. Documented in this SAND report are the results of an experimental study to determine the origin of the differences in the particle size distribution of the SP and TSP powders.

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Results 89976–90000 of 99,299
Results 89976–90000 of 99,299