This project seeks to provide vital data required to assess the consequences of a terrorist attack on a spent fuel transportation cask. One such attack scenario involves the use of conical shaped charges (CSC), which are capable of damaging a spent fuel transportation cask. In the event of such an attack, the amount of radioactivity that may be released as respirable aerosols is not known with great certainty. Research to date has focused on measuring the aerosol release from single short surrogate fuel rodlets subjected to attack by a small CSC device in various aerosol chamber designs. The last series of three experiments tested surrogate fuel rodlets made with depleted uranium oxide ceramic pellets in a specially designed double chamber aerosol containment apparatus. This robust testing apparatus was designed to prevent any radioactive release and allow high level radioactive waste disposal of the entire apparatus following testing of actual spent fuel rodlets as proposed. DOE and Sandia reviews of the project to date identified a number of issues. The purpose of this supplemental report is to address and document the DOE review comments and to resolve the issues identified in the Sandia technical review.
Recent papers have used Fiedler's definition of algebraic connectivity to show that network robustness, as measured by node-connectivity and edge-connectivity, can be increased by increasing the algebraic connectivity of the network. By the definition of algebraic connectivity, the second smallest eigenvalue of the graph Laplacian is a lower bound on the node-connectivity. In this paper we show that for circular random lattice graphs and mesh graphs algebraic connectivity is a conservative lower bound, and that increases in algebraic connectivity actually correspond to a decrease in node-connectivity. This means that the networks are actually less robust with respect to node-connectivity as the algebraic connectivity increases. However, an increase in algebraic connectivity seems to correlate well with a decrease in the characteristic path length of these networks - which would result in quicker communication through the network. Applications of these results are then discussed for perimeter security.
There are indications that corrective actions, as implemented at Sandia National Laboratories are not fully adequate. Review of independent audits spanning multiple years provides evidence of recurring issues within the same or similar operations and programs. Several external audits have directly called into question the ability Sandia's assessment and evaluation processes to prevent recurrence. Examples of repeated findings include lockout/tagout programs, local exhaust ventilation controls and radiological controls. Recurrence clearly shows that there are underlying systemic factors that are not being adequately addressed by corrective actions stemming from causal analyses. Information suggests that improvements in the conduct of causal analyses and, more importantly, in the development of subsequent corrective actions are warranted. Current methodolgies include Management Oversight Risk Tree, developed in the early 1970s and Systemic Factors Analysis. Recommendations for improvements include review of other causal analysis systems, training, improved formality of operations, improved documentation, and a corporate method that uses truly systemic solutions. This report was written some years ago and is being published now to form the foundation for current, follow-on reports being developed. Some outdated material is recognized but is retained for report completeness.
Measurements of the operating characteristics of a 1064 nm pumped potassium titanyl phosphte (KTP) optical parametric oscillator (OPO) were carried out at the Electro Optics Systems Laboratory of Georgia Tech Research Institute (GTRI). The OPO was developed by Sandia National Laboratories and employs a nonplanar image-rotating geometry that is known by the acronym RISTRA, denoting Rotated Image Singly-Resonant Twisted RectAngle. The OPO was configured for pumping by the 1064 nm fundamental wavelength of a Q-switched Nd:YAG laser to generate a signal wavelength at 1627 nm and idler wavelength at 3074.8 nm. GTRI will be incorporate the OPO into a multi-wavelength lidar platform called the Integrated Atmospheric Characterization System (IACS). Prior to completion of the system design for the IACS platform, personnel at GTRI carried out a series of risk reduction experiments to measure the operating characteristics of the OPO. Sandia's role in this effort included technical assistance with numerical modeling of OPO performance, selection of nonlinear optical crystals, specification of cavity-mirror dielectric coatings, selection of vendors for optical components, and advice concerning integration of the RISTRA OPO into the IACS platform. This report describes results of the risk reduction measurements and it also provides some background information on the operating characteristics of RISTRA OPO's but is not intended to be a tutorial. A working knowledge of pulsed solid-state lasers, laser cavity modes, laser beam quality and beam propagation, and three-wave mixing in nonlinear crystals, is useful.
Sandia National Laboratories performed an assessment of the benefits of energy storage for the Kauai Island Utility Cooperative. This report documents the methodology and results of this study from a generation and production-side benefits perspective only. The KIUC energy storage study focused on the economic impact of using energy storage to shave the system peak, which reduces generator run time and consequently reduces fuel and operation and maintenance (O&M) costs. It was determined that a 16-MWh energy storage system would suit KIUC's needs, taking into account the size of the 13 individual generation units in the KIUC system and a system peak of 78 MW. The analysis shows that an energy storage system substantially reduces the run time of Units D1, D2, D3, and D5 - the four smallest and oldest diesel generators at the Port Allen generating plant. The availability of stored energy also evens the diurnal variability of the remaining generation units during the off- and on-peak periods. However, the net economic benefit is insufficient to justify a load-leveling type of energy storage system at this time. While the presence of storage helps reduce the run time of the smaller and older units, the economic dispatch changes and the largest most efficient unit in the KIUC system, the 27.5-MW steam-injected combustion turbine at Kapaia, is run for extra hours to provide the recharge energy for the storage system. The economic benefits of the storage is significantly reduced because the charging energy for the storage is derived from the same fuel source as the peak generation source it displaces. This situation would be substantially different if there were a renewable energy source available to charge the storage. Especially, if there is a wind generation resource introduced in the KIUC system, there may be a potential of capturing the load-leveling benefits as well as using the storage to dampen the dynamic instability that the wind generation could introduce into the KIUC grid. General Electric is presently conducting such a study and results of this study will be available in the near future. Another study conducted by Electric Power Systems, Inc. (EPS) in May 2006 took a broader approach to determine the causes of KIUC system outages. This study concluded that energy storage with batteries will provide stability benefits and possibly eliminate the load shedding while also providing positive voltage control. Due to the lack of fuel diversity in the KIUC generation mix, SNL recommends that KIUC continue its efforts to quantify the dynamic benefits of storage. The value of the dynamic benefits, especially as an enabler of renewable generation such as wind energy, may be far greater than the production cost benefits alone. A combination of these benefits may provide KIUC sufficient positive economic and operational benefits to implement an energy storage project that will contribute to the overall enhancement of the KIUC system.
The Annular Core Research Reactor (ACRR) is a swimming-pool type pulsed reactor that maintains an epithermal neutron flux and a nine-inch diameter central dry cavity. One of its uses is neutron and gamma-ray irradiation damage studies on electronic components under transient reactor power conditions. In analyzing the experimental results, careful attention must be paid to the kinetics associated with the reactor to ensure that the transient behavior of the electronic device is understood. Since the ACRR fuel maintains a substantial amount of beryllium, copious quantities of photoneutrons are produced that can significantly alter the expected behavior of the reactor power, especially following a reactor pulse. In order to understand these photoneutron effects on the reactor kinetics, the KIFLE transient reactor-analysis code was modified to include the photoneutron groups associated with the beryllium. The time-dependent behavior of the reactor power was analyzed for small and large pulses, assuming several initial conditions including following several pulses during the day, and following a long steady-state power run. The results indicate that, for these types of initial conditions, the photoneutron contribution to the reactor pulse energy can have a few to tens of percent effect.
A Linear Frequency-Modulated (LFM) chirp is a function with unit amplitude and quadratic phase characteristic. In a focused Synthetic Aperture Radar (SAR) image, a residual chirp is undesired for targets of interest, as it coarsens the manifested resolution. However, for undesired spurious signals, a residual chirp is often advantageous because it spreads the energy and thereby diminishes its peak value. In either case, a good understanding of the effects of a residual LFM chirp on a SAR Impulse Response (IPR) is required to facilitate system analysis and design. This report presents an analysis of the effects of a residual chirp on the IPR. As reference, there is a rich body of publications on various aspects of LFM chirps. A quick search reveals a plethora of articles, going back to the early 1950s. We mention here purely as trivia one of the earlier analysis papers on this waveform by Klauder, et al.
This report identifies current environmental operating parameters for the various test and support facilities at SNL/NM. The intent of this report is solely to provide the limits which bound the facilities' operations. Understanding environmental limits is important to maximizing the capabilities and working within the existing constraints of each facility, and supports the decision-making process in meeting customer requests, cost and schedule planning, modifications to processes, future commitments, and use of resources. Working within environmental limits ensures that mission objectives will be met in a manner that protects human health and the environment. It should be noted that, in addition to adhering to the established limits, other approvals and permits may be required for specific projects.
In this report, we summarize our work on developing a production level capability for modeling brine thermodynamic properties using the open-source code Cantera. This implementation into Cantera allows for the application of chemical thermodynamics to describe the interactions between a solid and an electrolyte solution at chemical equilibrium. The formulations to evaluate the thermodynamic properties of electrolytes are based on Pitzer's model to calculate molality-based activity coefficients using a real equation-of-state (EoS) for water. In addition, the thermodynamic properties of solutes at elevated temperature and pressures are computed using the revised Helgeson-Kirkham-Flowers (HKF) EoS for ionic and neutral aqueous species. The thermodynamic data parameters for the Pitzer formulation and HKF EoS are from the thermodynamic database compilation developed for the Yucca Mountain Project (YMP) used with the computer code EQ3/6. We describe the adopted equations and their implementation within Cantera and also provide several validated examples relevant to the calculations of extensive properties of electrolyte solutions.
The Image Composition Engine for Tiles (IceT) is a high-performance sort-last parallel rendering library. In addition to providing accelerated rendering for a standard display, IceT provides the unique ability to generate images for tiled displays. The overall resolution of the display may be several times larger than any viewport that may be rendered by a single machine. This document is an overview of the user interface to IceT.
LIVA (Line-Imaging Velocimetry Analysis) is a program for reducing data of a line-imaging optically recording velocity interferometer system (ORVIS) diagnostic. LIVA uses the Fourier transform method to extract phase information from recorded streak camera images. The extracted phase shift is used to infer target velocity as a function of space and time. The program can be run in any current version of MATLAB (2008a or later) or as a Windows XP executable.
A technique for characterizing the pulse profile of a radio-frequency (RF) amplifier over a very wide power range under fast-pulsing conditions is presented. A pulse-modulated transmitter is used to drive a device under test (DUT) with a phase-coded signal that allows for an increased measurement range beyond standard techniques. A measurement receiver that samples points on the output pulse power profile and performs the necessary signal processing and coherent pulse integration, improving the detectability of low-power signals, is described. The measurement technique is applied to two sample amplifiers under fast-pulsing conditions with a pulsewidth of 250 ns at 3-GHz carrier frequency. A full measurement range of greater than 160 dB is achieved, extending the current state of the art in pulse-profiling techniques.
Explosive growth in photovoltaic markets has fueled new creative approaches that promise to cut costs and improve reliability of system components. However, market demands require rapid development of these new and innovative technologies in order to compete with more established products and capture market share. Often times diagnostics that assist in R&D do not exist or have not been applied due to the innovative nature of the proposed products. Some diagnostics such as IR imaging, electroluminescence, light IV, dark IV, x-rays, and ultrasound have been employed in the past and continue to serve in development of new products, however, innovative products with new materials, unique geometries, and previously unused manufacturing processes require additional or improved test capabilities. This fast-track product development cycle requires diagnostic capabilities to provide the information that confirms the integrity of manufacturing techniques and provides the feedback that can spawn confidence in process control, reliability and performance. This paper explores the use of digital radiography and computed tomography (CT) with other diagnostics to support photovoltaic R&D and manufacturing applications.
A combined experimental and constitutive modeling program for weak porous sandstone deformation is described. A series of axisymmetric compression tests were performed over a range of mean stresses to study dilatational, compactional and transitional regimes. Experimental results were used both to derive constitutive parameters for testing localization theory and to parameterize a poroelastic-plastic model. Observed strain localization, imaged syn-deformationally using acoustic emissions, includes high- and low-angle shear and low angle compactional features or 'bands'. Isotropic elastic moduli measured via unloading loops show a progressive degradation pre-failure as decreasing functions of work-conjugate plastic strains and increasing functions of stress magnitude. The degradation pathway is unique for samples which underwent localization versus those that underwent spatially pervasive pore collapse. Total shear and volume strains are partitioned into elastic and plastic portions including the ''coupling'' strain associated with modulus degradation. Plastic strain calculated with and without the coupling term is compared with regard to localization predictions. Both coupled and uncoupled cases predict high angle shear bands for uniaxial and low mean stress conditions on the dilatational side of the yield surface. Uncoupled predictions show progressively lower angle shear bands approaching the transitional regime (stress conditions approaching the 'cap' surface). When elastic-plastic coupling is accounted for, compaction bands are predicted for the transitional regime, as are observed in the experiments. Finite element modeling efforts are described using a 3-invariant, mixed-hardening, continuous yield surface, elasto-plasticity model that includes several features important for porous sandstone constitutive behavior and observed experimentally, including non-associativity, nonlinear elasticity, elastic-plastic coupling, and kinematic hardening. Modeled deformational behavior attending stress paths relevant for several reservoir production scenarios are described.