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2023 Annual Report of Available Drawdowns for Each Oil Storage Cavern in the Strategic Petroleum Reserve

Hart, David B.

DOE maintains an up-to-date documentation of the number of available full drawdowns of each of the caverns at the U.S. Strategic Petroleum Reserve (SPR). This information is important for assessing the SPR’s ability to deliver oil to domestic oil companies expeditiously if national or world events dictate a rapid sale and deployment of the oil reserves. Sandia was directed to develop and implement a process to continuously assess and report the evolution of drawdown capacity, the subject of this report. This report covers impacts on drawdown availability due to SPR operations during Calendar Year 2022. A cavern has an available drawdown if, after that drawdown, the long-term stability of the cavern, the cavern field, or the oil quality are not compromised. Thus, determining the number of available drawdowns requires the consideration of several factors regarding cavern and wellbore integrity and stability, including stress states caused by cavern geometry and operations, salt damage caused by dilatant and tensile stresses, the effect of enhanced creep on wellbore integrity, and the sympathetic stress effect of operations on neighboring caverns. Finite-element geomechanical models have been used to determine the stress states in the pillars following successive drawdowns. By computing the tensile and dilatant stresses in the salt, areas of potential structural instability can be identified that may represent red flags for additional drawdowns. These analyses have found that many caverns will maintain structural integrity even when grown via drawdowns to dimensions resulting in a pillar-to-diameter ratio of less than 1.0. The analyses have also confirmed that certain caverns should only be completely drawn down one time. As the SPR caverns are utilized and partial drawdowns are performed to remove oil from the caverns (e.g., for oil sales, purchases, or exchanges authorized by the Congress or the President), the changes to the cavern caused by these procedures must be tracked and accounted for so that an ongoing assessment of the cavern’s drawdown capacity may be continued. A methodology for assessing and tracking the available drawdowns for each cavern is reiterated. This report is the latest in a series of annual reports, and it includes the baseline available drawdowns for each cavern, and the most recent assessment of the evolution of drawdown expenditures. A total of 222 million barrels of oil were released in calendar-year 2022. A nearly-equal amount of raw water was injected, resulting in an estimated 34 million barrels of cavern leaching. Twenty caverns have now expended a full drawdown. Cavern BC 18 has expended all its baseline available drawdowns, and has no drawdowns remaining. Cavern BM 103 has expended one of its two baseline drawdowns, and is now a single-drawdown cavern. All other caverns with an expenditure went from at-least-5 to at-least-4 remaining drawdowns.

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Ti-6Al-4V to over 1.2 TPa: Shock Hugoniot experiments, ab initio calculations, and a broad-range multiphase equation of state

Physical Review B

Laros, James H.; Cochrane, Kyle C.; Knudson, Marcus D.; Ao, Tommy A.; Blada, Caroline B.; Jackson, Jerry; Gluth, Jeffry; Hanshaw, Heath L.; Scoglietti, Edward; Crockett, Scott D.

Titanium alloys are used in a large array of applications. In this work we focus our attention on the most used alloy, Ti-6Al-4V (Ti64), which has excellent mechanical and biocompatibility properties with applications in aerospace, defense, biomedical, and other fields. Here we present high-fidelity experimental shock compression data measured on Sandia's Z machine. We extend the principal shock Hugoniot for Ti64 to more than threefold compression, up to over 1.2 TPa. We use the data to validate our ab initio molecular dynamics simulations and to develop a highly reliable, multiphase equation of state (EOS) for Ti64, spanning a broad range of temperature and pressures. The first-principles simulations show very good agreement with Z data and with previous three-stage gas gun data from Sandia's STAR facility. The resulting principal Hugoniot and the broad-range EOS and phase diagram up to 10 TPa and 105 K are suitable for use in shock experiments and in hydrodynamic simulations. The high-precision experimental results and high-fidelity simulations demonstrate that the Hugoniot of the Ti64 alloy is stiffer than that of pure Ti and reveal that Ti64 melts on the Hugoniot at a significantly lower pressure and temperature than previously modeled.

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Industrial PLC Network Modeling and Parameter Identification Using Sensitivity Analysis and Mean Field Variational Inference

Sensors

Ching, David C.; Safta, Cosmin S.; Reichardt, Thomas A.; Wonnacott, Raelynn; Rashkin, Lee; Chilleri, John

A multiple input multiple output (MIMO) power line communication (PLC) model for industrial facilities was developed that uses the physics of a bottom-up model but can be calibrated like top-down models. The PLC model considers 4-conductor cables (three-phase conductors and a ground conductor) and has several load types, including motor loads. The model is calibrated to data using mean field variational inference with a sensitivity analysis to reduce the parameter space. The results show that the inference method can accurately identify many of the model parameters, and the model is accurate even when the network is modified.

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NSE workplace of the future: Enabling a LPS ready workforce

Keller, Elizabeth J.; Landis, Lynette; Baker, Brent; Bowen, Dan; Carlson, Nils; Crone, Brian; Danielson, Tom; Fliermans, Matthew; Gupta, Rajan; Howieson, Susannah; Kelly, Rand; Kennedy, Ryan; Knepper, Paula; Lanier, Andrekka (Aj); Lennon, Sarah; Mallin, Monte; Mohagheghi, Amir H.; Orr, Marilee; Reed, Danielle; Riley, David; Stevens, Noah; Templeton, Dennise; Williams, Brandon; Wolf, Ambrose

The future mission success of the Nuclear Security Enterprise (NSE) relies on our workforce and our workplace. The 2022 Nuclear Posture Review notes that “the health of the enterprise depends critically on recruiting and retaining a skilled and diverse workforce” and the 2022 National Nuclear Security Administration (NNSA) Strategic Vision articulates a commitment to “recruit, invest in, and nourish a high-performing, diverse, and flexible workforce that can meet the unique policy, technical, and leadership needs of our mission today and well into the future.”

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Remote Sensing Low Signal-to-Noise-Ratio Target Detection Enhancement

Sensors

Ma, Tian J.; Anderson, Robert J.

In real-time remote sensing application, frames of data are continuously flowing into the processing system. The capability of detecting objects of interest and tracking them as they move is crucial to many critical surveillance and monitoring missions. Detecting small objects using remote sensors is an ongoing, challenging problem. Since object(s) are located far away from the sensor, the target’s Signal-to-Noise-Ratio (SNR) is low. The Limit of Detection (LOD) for remote sensors is bounded by what is observable on each image frame. In this paper, we present a new method, a “Multi-frame Moving Object Detection System (MMODS)”, to detect small, low SNR objects that are beyond what a human can observe in a single video frame. This is demonstrated by using simulated data where our technology-detected objects are as small as one pixel with a targeted SNR, close to 1:1. We also demonstrate a similar improvement using live data collected with a remote camera. The MMODS technology fills a major technology gap in remote sensing surveillance applications for small target detection. Our method does not require prior knowledge about the environment, pre-labeled targets, or training data to effectively detect and track slow- and fast-moving targets, regardless of the size or the distance.

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Mobile Energy Storage Systems: A Grid-Edge Technology to Enhance Reliability and Resilience

IEEE Power and Energy Magazine

Chuangpishit, Shadi; Katiraei, Farid; Chalamala, Babu C.; Novosel, Damir

Increase in the number and frequency of widespread outages in recent years has been directly linked to drastic climate change necessitating better preparedness for outage mitigation. Severe weather conditions are experienced more frequently and on larger scales, challenging system operation and recovery time after an outage. The impact is more evident and concerning than before, considering the increased dependency on electricity in all aspects of our lives.

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Hardware-in-the-loop testing of a hydraulic wave energy power take-off system

Coe, Ryan G.; Leon Quiroga, Jorge A.; Bacelli, Giorgio B.; Spencer, Steven; Spinneken, Johannes; Gallegos-Patterson, D.

This report describes testing conducted related to the development of a “hydrostatic power takeoff” (HPTO) system for a wave energy converter. Tests were conducted with an experimental electric motor rig to provide preliminary results and de-risk future testing. Efficiency mapping tests were conducted as well as hardware-in-the-loop (HIL) testing. The results of the efficiency mapping tests provide good insight into how to systematically perform efficiency mapping tests. The HIL testing indicates good overall performance of the system and provides a stepping stone towards more complete system tests in the future.

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Results 2001–2100 of 96,771
Results 2001–2100 of 96,771