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Shear Behavior of Bedded Salt Interfaces under Direct Shear Loading

Sobolik, Steven; Reedlunn, Benjamin

Bedded salt contains interfaces between the host salt and other in situ materials such as clay seams, or different impurities such as anhydrite or polyhalite in contact with the salt. These inhomogeneities are thought to have first-order effects on the closure of nearby drifts and potential roof collapses. Despite their importance, characterizations of the peak shear strength and residual shear strength of interfaces in salt are extremely rare in the published literature. This paper presents results from laboratory experiments designed to measure the mechanical behavior of a bedding interface or clay seam as it is sheared. The series of laboratory direct shear tests reported in this paper were performed on several samples of materials from the Permian Basin in New Mexico. These tests were conducted at numerous normal and shear loads up to the expected in situ pre-mining stress conditions. Tests were performed on samples with a halite/clay contact, a halite/anhydrite contact, a halite/polyhalite contact, and on plain salt samples without an interface for comparison. Intact shear strength values were determined for all of the test samples along with residual values for the majority of the tests. The results indicated only a minor variation in shear strength, at a given normal stress, across all samples. This result was surprising because sliding along clay seams is regularly observed in the underground, suggesting the clay seam interfaces should be weaker than plain salt. Post-test inspections of these samples noted that salt crystals were intrinsic to the structure of the seam, which probably increased the shear strength as compared to a typical clay seam.

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TYPE SAND Report YEAR 2019
DOIOSTI

Quantification of MagLIF Morphology using the Mallat Scattering Transformation

Glinsky, Michael E.; Moore, Thomas; Foulk, James W.; Weis, Matthew R.; Jennings, Christopher A.; Ampleford, David J.; Harding, Eric H.; Knapp, P.F.; Gomez, Matthew R.; Lussiez, Sophia E.

The morphology of the stagnated plasma resulting from Magnetized Liner Inertial Fusion (MagLIF) is measured by imaging the self-emission x-rays coming from the multi-keV plasma, and the evolution of the imploding liner is measured by radiographs. Equivalent diagnostic response can be derived from integrated rad-MHD simulations from programs such as Hydra and Gorgon. There have been only limited quantitative ways to compare the image morphology, that is the texture, of simulations and experiments. We have developed a metric of image morphology based on the Mallat Scattering Transformation (MST), a transformation that has proved to be effective at distinguishing textures, sounds, and written characters. This metric has demonstrated excellent performance in classifying ensembles of synthetic stagnation images. We use this metric to quantitatively compare simulations to experimental images, cross experimental images, and to estimate the parameters of the images with uncertainty via a linear regression of the synthetic images to the parameter used to generate them. This coordinate space has proved very adept at doing a sophisticated relative back-ground subtraction in the MST space. This was needed to compare the experimental self emission images to the rad-MHD simulation images. We have also developed theory that connects the transformation to the causal dynamics of physical systems. This has been done from the classical kinetic perspective and from the field theory perspective, where the MST is the generalized Green's function, or S-matrix of the field theory in the scale basis. From both perspectives the first order MST is the current state of the system, and the second order MST are the transition rates from one state to another. An efficient, GPU accelerated, Python implementation of the MST was developed. Future applications are discussed.

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TYPE SAND Report YEAR 2019
DOIOSTI

Topological Quantum Materials for Quantum Computation

Nenoff, Tina M.; Chou, Stanley S.; Dickens, Peter T.; Modine, Normand A.; Yu, Wenlong; Lee, Stephen R.; Sapkota, Keshab R.; Wang, George T.; Wendt, Joel R.; Medlin, Douglas L.; Leonard, Francois; Pan, Wei

Recent years have seen an explosion in research efforts discovering and understanding novel electronic and optical properties of topological quantum materials (TQMs). In this LDRD, a synergistic effort of materials growth, characterization, electrical-magneto-optical measurements, combined with density functional theory and modeling has been established to address the unique properties of TQMs. Particularly, we have carried out extensive studies in search for Majorana fermions (MFs) in TQMs for topological quantum computation. Moreover, we have focused on three important science questions. 1) How can we controllably tune the properties of TQMs to make them suitable for quantum information applications? 2) What materials parameters are most important for successfully observing MFs in TQMs? 3) Can the physical properties of TQMs be tailored by topological band engineering? Results obtained in this LDRD not only deepen our current knowledge in fundamental quantum physics but also hold great promise for advanced electronic/photonic applications in information technologies.

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TYPE SAND Report YEAR 2019
DOIOSTI

Nonlinear WEC optimized geometric buoy design for efficient reactive power requirements

OCEANS 2019 MTS/IEEE Seattle, OCEANS 2019

Wilson, David G.; Robinett, Rush D.; Bacelli, Giorgio; Abdelkhalik, Ossama; Weaver, Wayne W.; Coe, Ryan G.

This paper presents a nonlinear geometric buoy design for Wave Energy Converters (WECs). A nonlinear dynamic model is presented for an hour glass (HG) configured WEC. The HG buoy operates in heave motion or as a single Degree-of-Freedom (DOF). The unique formulation of the interaction between the buoy and the waves produces a nonlinear stiffening effect that provides the actual energy storage or reactive power during operation. A Complex Conjugate Control (C3) with a practical Proportional-Derivative (PD) controller is employed to optimize power absorption for off-resonance conditions and applied to a linear right circular cylinder (RCC) WEC. For a single frequency the PDC3 RCC buoy is compared with the HG buoy design. A Bretschneider spectrum of wave excitation input conditions are reviewed and evaluated for the HG buoy. Numerical simulations demonstrate power and energy capture for the HG geometric buoy design which incorporates and capitalizes on the nonlinear geometry to provide reactive power for the single DOF WEC. By exploiting the nonlinear physics in the HG design simplified operational performance is observed when compared to an optimized linear cylindrical WEC. The HG steepness angle α with respect to the wave is varied and initially optimized for improved energy capture.

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TYPE Conference Poster YEAR 2019
DOIOSTIScopus

WEC array networked microgrid control design and energy storage system requirements

OCEANS 2019 MTS/IEEE Seattle, OCEANS 2019

Weaver, Wayne W.; Hagmuller, Alex; Ginsburg, Max; Wilson, David G.; Bacelli, Giorgio; Robinett, Rush D.; Coe, Ryan G.; Gunawan, Budi

Wave Energy Converter (WEC) technologies transform power from the waves to the electrical grid. WEC system components are investigated that support the performance, stability, and efficiency as part of a WEC array. To this end, Aquaharmonics Inc took home the 1.5 million grand prize in the 2016 U.S. Department of Energy Wave Energy Prize, an 18-month design-build-test competition to increase the energy capture potential of wave energy devices. Aquaharmonics intends to develop, build, and perform open ocean testing on a 1: 7 scale device. Preliminary wave tank testing on the mechanical system of the 1: 20 scale device has yielded a data-set of operational conditions and performance. In this paper, the Hamiltonian surface shaping and power flow control (HSSPFC) method is used in conjunction with scaled wave tank test data to explore the design space for the electrical transmission of energy to the shore-side power grid. Of primary interest is the energy storage system (ESS) that will electrically link the WEC to the shore. Initial analysis results contained in this paper provide a trade-off in storage device performance and design selection.

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TYPE Conference Poster YEAR 2019
DOIOSTIScopus

Detailed Statistical Models of Host-Based Data for Detection of Malicious Activity

Foulk, James W.; Chen, Guenevere; Adams, Susan S.; Bryant, Ross D.; Haas, Jason J.; Johnson, Nicholas; Romanowich, Paul; Roy, Krishna; Shakamuri, Mayuri; Foulk, James W.; Ting, Christina

The cybersecurity research community has focused primarily on the analysis and automation of intrusion detection systems by examining network traffic behaviors. Expanding on this expertise, advanced cyber defense analysis is turning to host-based data to use in research and development to produce the next generation network defense tools. The ability to perform deep packet inspection of network traffic is increasingly harder with most boundary network traffic moving to HTTPS. Additionally, network data alone does not provide a full picture of end-to-end activity. These are some of the reasons that necessitate looking at other data sources such as host data. We outline our investigation into the processing, formatting, and storing of the data along with the preliminary results from our exploratory data analysis. In writing this report, it is our goal to aid in guiding future research by providing foundational understanding for an area of cybersecurity that is rich with a variety of complex, categorical, and sparse data, with a strong human influence component. Including suggestions for guiding potential directions for future research.

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TYPE SAND Report YEAR 2019
DOIOSTI

Annual BTMS Testing Section (SNL)

Perdue, Brian R.; Karulkar, Mohan P.; Torres-Castro, Loraine

One of the first milestones of the Behind the Meter Storage (BTMS) program was to develop testing protocols so that the state-of-the-art cell chemistries and form factors could be evaluated against BTMS aggressive performance and lifetime metrics. To help guide this conversation, a pack estimation calculation was run. At the time the team was assuming a worst-case scenario in which the battery alone would need to charge an electric vehicle in 15 minutes with no support from the grid. This calculation varied the amount of current applied by each string or module in the storage system and estimated how many cells (and estimated cost) would be needed to charge an electric vehicle in 15 minutes under the current applied.

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TYPE Other Report YEAR 2019
DOIOSTI

Simulations of Pipe Overpack Container Compaction at the Waste Isolation Pilot Plant

Reedlunn, Benjamin; Foulk, James W.

The Waste Isolation Pilot Plant (WIPP) is an operating geologic repository in southeastern New Mexico for transuranic (TRU) waste from nuclear defense activities. Past nuclear criticality concerns have generally been low at the WIPP due to the low initial concentration of fissile material and the natural tendency of fissile solute to disperse during fluid transport in porous media (Rechard et al. 2000). On the other hand, the list of acceptable WIPP waste types has expanded over the years to include Criticality Control Overpack (CCO) containers and Pipe Overpack (POP) containers. Containers bound for WIPP are bundled together in hexagon shaped 7-packs (six containers surround one container in the center). Two 7-packs are often combined into a TRUPACT-II package for a total of 14 containers. Most TRUPACT-II packages are restricted to a maximum fissile mass equivalent to plutonium (FMEP) between 0.1 and 0.38 kg, but a CCO TRUPACT-II package and a POP TRUPACT-II package are respectively permitted to have 5.32 kg and 2.80 kg FMEP (see Section 3 of US DOE (2013)). Consequently, CCO container criticality after emplacement at the WIPP was evaluated in Saylor and Scaglione (2018), and Oak Ridge National Laboratories is currently at work on POP container criticality analyses.

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TYPE SAND Report YEAR 2019
DOIOSTI

Hydrogen Quantitative Risk Assessment (Annual Progress Report)

Ehrhart, Brian D.; Muna, Alice B.; Lafleur, Angela (Chris); Glover, Austin M.; Baird, Austin R.

DOE has identified consistent safety, codes, and standards as a critical need for the deployment of hydrogen technologies, with key barriers related to the availability and implementation of technical information in the development of regulations, codes, and standards. Advances in codes and standards have been enabled by risk-informed approaches to create and implement revisions to codes, such as National Fire Protection Association (NFPA) 2, NFPA 55, and International Organization for Standardization (ISO) Technical Specification (TS)-19880-1. This project provides the technical basis for these revisions, enabling the assessment of the safety of hydrogen fuel cell systems and infrastructure using QRA and physics-based models of hydrogen behavior. The risk and behavior tools that are developed in this project are motivated by, shared directly with, and used by the committees revising relevant codes and standards, thus forming the scientific basis to ensure that code requirements are consistent, logical, and defensible.

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TYPE Other Report YEAR 2019
DOIOSTI

Innovative Linear and Nonlinear Solvers for Simulating Multiphase Flow within Large-Scale Engineered Subsurface Systems

Park, Heeho D.

Numerical simulation of non-isothermal multiphase porous flow combined with reactive transport is used in a wide range of applications, which include nuclear waste repositories, enhanced recovery of petroleum reservoirs, contaminant remediation, geothermal engineering, and carbon sequestration. Understanding and predicting underground phenomena can have enormous impact on how to deal with world issues like climate change, clean water, and renewable energy. The main motivation for this proposal arises from safety assessment of future nuclear waste repositories using the U.S. Department of Energy (DOE) Geologic Disposal Safety Assessment (GDSA) Framework, and performance assessment (PA) for Waste Isolation Pilot Plant (WIPP), the nation's only active nuclear waste repository in Carlsbad, New Mexico. I am a technical staff member at Sandia National Laboratories involved in both projects.

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TYPE Other Report YEAR 2019
DOIOSTI

Diagnostic Tool for Measuring Early Chemical Signatures of Pond Crash

Moorman, Matthew W.

The DOE is devoted to improving national energy security and reducing carbon emissions through the development of renewable alternatives to fossil fuel usage. This work demonstrates a pathway to improve the feasibility of large-scale biofuel production by reducing the occurrences of pond failures and their associated economic burdens. We have done this by identifying unique volatile chemical signals that indicate predator attack on an algal biofuel pond. These volatiles are easy to collect in the field and could be rapidly analyzed for state-of- health monitoring. This will allow producers to intervene early during predator attack on a pond and minimize crop loss.

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TYPE SAND Report YEAR 2019
DOIOSTI

Hydrogen Stations for Urban Sites

Ehrhart, Brian D.; Bran Anleu, Gabriela A.; Ye, Dongmei Y.; Hecht, Ethan S.; Muna, Alice B.; Lafleur, Angela (Chris)

Additional fueling stations need to be constructed in the U.S. to enable the wide-spread adoption of fuel cell electric vehicles. A wide variety of private and public stakeholders are involved in the development of this hydrogen fueling infrastructure. Each stakeholder has particular needs in the station planning, development, and operation process that may include evaluation of potential sites and requirements, understanding the components in a typical system, and/or improving public acceptance of this technology. Publicly available templates of representative station designs can be used to meet many of these stakeholder needs. These 'Reference Stations' help reduce the cost and speed the deployment of hydrogen stations by providing a common baseline with which to start a design, enabling quick assessment of the suitability of a particular site for a hydrogen station, and identifying contributors to poor economics and research and development areas for certain station designs.

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TYPE Other Report YEAR 2019
DOIOSTI

MELCOR Code Change History: Revision 11932 to 14959

Phillips, Jesse

This document summarily provides brief descriptions of the MELCOR code enhancement made between code revision number 11932 and 14959. Revision 11932 represents the last official code release; therefore, the modeling features described within this document are provided to assist users that update to the newest official MELCOR code release, 14959. Along with the newly updated MELCOR Users' Guide and Reference Manual, users will be aware and able to assess the new capabilities for their modeling and analysis applications.

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TYPE SAND Report YEAR 2019
DOIOSTI
Results 20201–20400 of 99,299
Results 20201–20400 of 99,299