This report describes the mechanical characterization of six types of woven composites that Sandia National Laboratories are interested in. These six composites have various combinations of two types of fibers (Carbon-IM7 and Glass-S2) and three types of resins (UF-3362, TC275-1, TC350-1). In this work, two sets of experiments were conducted: quasi-static loading with displacement rate of 2 mm/min (1.3x10^(-3) in/s) and high rate loading with displacement of 5.08 m/s (200 in/s). Quasi-static experiments were performed at three loading orientations of 0°, 45°, 90° for all the six composites to fully characterize their mechanical properties. The elastic properties Young's modulus and Poisson's ratio, as well as ultimate stress and strain were obtained from the quasi-static experiments. The high strain rate experiments were performed only on glass fiber composites along 0° angle of loading. The high rate experiments were mainly to study how the strain rate affects the ultimate stress of the glass-fiber composites with different resins.
Efficiently performing predictive studies of irradiated particle-laden turbulent flows has the potential of providing significant contributions towards better understanding and optimizing, for example, concentrated solar power systems. As there are many uncertainties inherent in such flows, conducting uncertainty quantification analyses is fundamental to improve the predictive capabilities of the numerical simulations. For largescale, multi-physics problems exhibiting high-dimensional uncertainty, characterizing the stochastic solution presents a significant computational challenge as many methods require a large number of high-fidelity, forward model solves. This requirement results in the need for a possibly infeasible number of simulations when a typical converged high-fidelity simulation requires intensive computational resources. To reduce the cost of quantifying high-dimensional uncertainties, we investigate the application of a non-intrusive, bi-fidelity approximation to estimate statistics of quantities of interest associated with an irradiated particle-laden turbulent flow. This method relies on exploiting the low-rank structure of the solution to accelerate the stochastic sampling and approximation processes by means of cheaper-to-run, lower fidelity representations. The application of this bi-fidelity approximation results in accurate estimates of the QoI statistics while requiring a small number of high-fidelity model evaluations. It also enables efficient computation of sensitivity analyses which highlight that epistemic uncertainty plays an important role in the solution of irradiated, particle-laden turbulent flow.
This work is to characterize the mechanical properties of the selected composites along both on- and off- fiber axes at the ambient loading condition (+25°C), as well as at the cold (-54°C), and high temperatures (+71°C). A series of tensile experiments were conducted at different material orientations of 0°, 22.5°, 45°, 67.5°, 90° to measure the ultimate strength and strain $σ_{f}, ϵ_{f}$, and material engineering constants, including Young's modulus Ε and Poisson's ratio ν. The composite materials in this study were one carbon composite carbon (AS4C/UF3662) and one E-galss (E-glass/UF3662) composite. They both had the same resin of UF 3362, but with different fibers of carbon AS4C and E-glass. The mechanical loading in this study was limited to the quasi-static loading of 2 mm/min (1.3x10^(-3) in/s), which was equivalent to 5x10(-4) strain rate. These experimental data of the mechanical properties of composites at different loading directions and temperatures were summarized and compared. These experimental results provided database for design engineers to optimize structures through ply angle modifications and for analysts to better predict the component performance.
Subsurface seals and wellbores are central to oil and gas production, as well as the containment of subsurface fluids (e.g. methane or CO2 storage). Studying the evolution of cement-geomaterial interfaces of such systems is important to further our understanding of the fundamental physics and chemistry that underpins catastrophic wellbore seal failure. The objective of this study is to characterize cementitious and geomaterials through pore structure analysis and geochemical modeling. A variety of methods exist to characterize the pore structures and mineralogy of porous systems like cements and subsurface host rocks. This study will utilize traditional porosimetry techniques such as BET and IP, as well as more advanced methods using electron image analysis, to gain a more accurate understanding of pore geometries. The results of this study can help further the understanding of how cementitious materials will evolve, and can be used as inputs to field scale models used to predict wellbore behavior over time.
Mutual vulnerability to strategic forces seems to remain the de facto foundation for strategic stability across the U.S.-Russia and U.S.-China dyadic relationships; This work has suggested the bomber force tasked with delivering the LRSO is characterized by relatively long flight times and rich signature sets which make its use inconsistent with the requirements for a disarming first-strike. Therefore, the LRSO would not be expected to disrupt mutual vulnerability by making a disarming strike more possible or attractive; Even if a stealthy air-launched cruise missile is paired with a stealth bomber aircraft, the signatures associated with bomber generation and aerial refueling from non-stealth tanker aircraft make it unlikely the LRSO could be launched against a peer or near-peer nation-state without advance warning; To the extent a nuclear armed air-launched cruise missile deters would-be U.S. adversaries from nuclear use, maintaining a survivable weapon system is crucial for maintaining that stable deterrent effect. A modern stand-off weapon and stealth delivery platform increase the probability this capability will be maintained in the future against other nations' increasingly capable A2/AD systems; The LRSO has been touted as a flexible option to deter, or conduct should deterrence fail, limited nuclear strikes pursuant to Russia's reported "escalate-to-deescalate" doctrine. The concept of limited nuclear use is still intensely debated, and there is no guarantee that escalation could be controlled even with tailored LRSO employment; The challenge of warhead discrimination has not historically led to a nuclear response to a cruise missile launch, but there is no guarantee that cannot change. Having accurate military intelligence coupled with discerning analysis of the context in which cruise missiles are employed (e.g., how escalated is the conflict, how many missiles have been launched, have there been signatures of strategic force mobilization, or has the nuclear threshold been crossed?) will likely be essential for reducing the danger of misperception. Developing norms and/or communication channels in the aforementioned dyadic relationships may also further these ends. In sum, this work has identified and analyzed many of the major arguments in the debate regarding the LRSO's impact on strategic stability. During this study and survey of other nation's conceptions of strategic stability, it became clear that the LRSO is neither inherently stabilizing or destabilizing; rather, it is one instrument in addition to unambiguous U.S. policy, clear messaging, and signaling of intent that may promote stability by reducing the risk of miscalculation and unintended escalation.
Goal: create an efficient computational tool capable of predicting the complex, nonlinear response of truss lattices containing extremely Iarge numbers of beams and nodes.
The primary subject of this Report is the description and characterization of results (voltages, currents, radiation dose and dose-rates) from the HERMES accelerator operated in the Outdoor Mode. The shots described range from 10266 – 10313, and were taken in late 2016. In the course of determining the most accurate estimates of voltage and current, a prescriptive procedure is developed to process the raw data posted to the HERMES database. The current estimates are tied to voltage determination using the MITL theory of Mendel, as modified by Schumer and Ottinger. The converter currents are accurately recorded due to newly calibrated monitors at the converter location. Additional historical information about the development of the HERMES current monitor set is included to enhance the archival value of this Report. The evolution of the TLD faceplate profile from non-peaked center to center-peaked is discussed, with hypotheses as to the cause. The prescriptive procedure discussed herein is accurate as of the day of printing. Should the prescription be modified and updated, this Report would also need updating.
This project will enable high-fidelity aerothermal simulations of hypersonic vehicles to be employed (1) to generate large databases with quantified uncertainties and (2) for rapid interactive simulation. The databases will increase the volume/quality of A4H data; rapid interactive simulation can enable arbitrary conditions/designs to be simulated on demand. We will achieve this by applying reduced-order-modeling techniques to aerothermal simulations.
On August 15th thru 17th, 2017 the Federal Radiological Monitoring and Assessment Center (FRMAC) Laboratory Analysis division, the FRMAC Fly Away Laboratory (FAL), the FRMAC Assessment division, and the Mobile Environmental Response Laboratory (MERL) held a training and capstone event for staff from the Environmental Protection Agency (EPA), Remote Sensing Laboratory (RSL), Lawrence Livermore National Laboratory (LLNL), and Sandia National Laboratories (SNL). LAB-100, "Sample Control Training", LAB-200 "QA Specialist Training", and LAB-300 "Laboratory Analysis Manager Training" was given the first two days of the event. The purpose of the training and capstone event was to meet training requirements for billeted FRMAC Lab Analysis staff from RSL, LLNL, and SNL as well as raise awareness of the FRMAC Lab Analysis process with EPA staff as part of a Federal Emergency Management Agency — Nuclear Incident Response Team (FEMA-NIRT) laboratory standardization project. An objective of the standardization project was to help improve the transition of operations from DOE to EPA during a response. To do this effectively, detailed knowledge of the FRMAC Lab Analysis process by the EPA is needed. This training provided a good opportunity for this knowledge transfer. A capstone was held after the two-day training event to allow participants to practice the skills they learned in a realistic scenario. A scenario that was previously developed for a quarterly Consequence Management drill (i.e. Dark Phoenix) was used as the basis for the capstone, with laboratory analysis focused injects used to drive the exercise play. Each position within the FRMAC Lab Analysis Division exercised to specific objectives and helped to uncover gaps in the established processes. The lessons learned during this capstone are broken out in the following categories: Sample Control, In-Situ Gamma Spectroscopy, Analysis Request Forms (ARF), Shipping, QA/QC, Fly Away Laboratory (FAL), and Management.
The classical problem of calculating the volume of the union of d-dimensional balls is known as "Union Volume." We present line-sampling approximation algorithms for Union Volume. Our methods may be extended to other Boolean operations, such as setminus; or to other shapes, such as hyper-rectangles. The deterministic, exact approaches for Union Volume do not scale well to high dimensions. However, we adapt several of these exact approaches to approximation algorithms based on sampling. We perform local sampling within each ball using lines. We have several variations, depending on how the overlapping volume is partitioned, and depending on whether radial, axis-aligned, or other line patterns are used. Our variations fall within the family of Monte Carlo sampling, and hence have about the same theoretical convergence rate, 1 /$\sqrt{M}$, where M is the number of samples. In our limited experiments, line-sampling proved more accurate per unit work than point samples, because a line sample provides more information, and the analytic equation for a sphere makes the calculation almost as fast. We performed a limited empirical study of the efficiency of these variations. We suggest a more extensive study for future work. We speculate that different ball arrangements, differentiated by the distribution of overlaps in terms of volume and degree, will benefit the most from patterns of line samples that preferentially capture those overlaps. Acknowledgement We thank Karl Bringman for explaining his BF-ApproxUnion (ApproxUnion) algorithm [3] to us. We thank Josiah Manson for pointing out that spoke darts oversample the center and we might get a better answer by uniform sampling. We thank Vijay Natarajan for suggesting random chord sampling. The authors are grateful to Brian Adams, Keith Dalbey, and Vicente Romero for useful technical discussions. This work was sponsored by the Laboratory Directed Research and Development (LDRD) Program at Sandia National Laboratories. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Advanced Scientific Computing Research (ASCR), Applied Mathematics Program. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.
This report studies the efforts of the international community and the United States to verif)/ the denuclearization of various countries: Ukraine, South Africa, Iraq, Taiwan, and Libya. In doing so, it considers the verification of nuclear warhead destruction and the accounting of nuclear materials. Each case study contributes to the understanding we have of which verification procedures worked and which did not and what factors contributed to that success and which did not. The most important factor contributing to successful verification is the cooperation of the subject country. If a country has made the strategic decision to cooperate, then it is possible that verification can be successful. If the country chooses not to cooperate, verification might rest on random and unpredictable events. This unpredictability of verification is politically unacceptable. Even if verification is judged to be successful by the implementing agencies, outsiders can cast doubts on it by pointing out small and potentially unavoidable errors in material amounts verified. It is vitally important to systematically preserve forensic evidence, especially shipping and receiving records to avoid just such issues. Historically, such records are the most important evidence in verifying denuclearization. Technology is far less important than forensic analysis of records. It does play a supporting role in verifying some declarations but there can be an enormous delay in drawing conclusions caused by the necessity to analyze statistically large samples of materials. The confidence one gets from such analysis can be delayed well past the time it is politically significant. The most important advance in technology would be to accelerate that sample analysis process.
The agenda for this presentation covers the Model Authorized Product — Realization (MAPR); Project Background; Data Collected; Observations & Findings; Next Steps; MBE Level 3+; Research on 3D interactive viewable(s) (3DIV).
This report considers plane wave coupling to a transmission line consisting of a wire above a conducting ground. Comparisons are made for the two types of available source models, along with a discussion about the decomposition of the line currents. Simple circuit models are constructed for the terminating impedances at the ends of the line including radiation effects. Results from the transmission line with these loads show good agreement with full wave simulations.