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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 775 records · Page 43

Advanced Seismic Fragility Modeling using Nonlinear Soil-Structure Interaction Analysis

The goal of this effort is to compare the seismic fragilities of a nuclear power plant system obtained by a traditional seismic probabilistic risk assessment (SPRA) and an advanced SPRA that utilizes Nonlinear Soil-Structure Interaction (NLSSI) analysis. Soil-structure interaction (SSI) response analysis for a traditional SPRA involves the linear analysis, which ignores geometric nonlinearities (i.e., soil and structure are glued together and the soil material undergoes tension when the structure uplifts). The NLSSI analysis will consider geometric nonlinearities.

31274, LWRS↗

Leveraging a Fundamental Understanding of Fracture Flow, Dynamic Permeability Enhancement, and Induced Seismicity to Improve Geothermal Energy Production

This project focused on assessment and discovery of fluid-rock interaction in geothermal reservoirs. We accomplished work in four main areas: 1) fracture formation and the relationship between fluid flow and shear failure, 2) assessment of fracture geometry and fluid permeability using novel acoustic measurements, 3) an improved understanding of how drilling, injection and geothermal production influence local seismicity, and 4) development of process based models for using induced seismicity to assess the critical stress-state in Earth’s crust. The majority of the work involved laboratory experiments and analysis of laboratory and numerical results. We created shear fractures under true triaxial stresses designed to mimic the stress state of a geothermal reservoir and we measured fracture permeability as a function of stress state and fluid pressure under these conditions. Our work shows that fracture permeability can be altered by transient changes in stress and fluid flow. We find that fluid pressure has an unexpectedly larger impact on permeability than does applied stress and we interpret that result in terms of fracture contact area and the law of effective stress. We employ elastic waves to image fractures in the lab and develop the theory to apply our work to geothermal reservoir scale. Our work documents changes in elastic wave speed prior to earthquake-like failure in the lab and we show how the frequency magnitude distribution of microseismic lab earthquakes can be used to assess the critical stress state around faults prior to failure.

15 GEOTHERMAL ENERGY↗

Seismic Testing of Glovebox Feedthrough Connectors and Vacuum Pumps

In the design of tritium processing systems, the glovebox stripper system processes the glovebox atmosphere to recover tritium released inside the glovebox confinement. The glovebox stripper system must also be capable of processing the additional in-leakage caused by a Design Basis Accident (DBA) earthquake, in order to maintain the glovebox pressure negative relative to the room. However, it is unknown how much additional leakage occurs from electrical bulkhead feedthrough connectors after a DBA event. As there are dozens of these connectors on a tritium glovebox system, the potential increase in in-leakage can be significant. One vital part of the glovebox stripper system are the vacuum pumps that maintain the negative atmosphere of the glovebox following a DBA earthquake. The pumps must be able to operate following an earthquake. One candidate pump is the Senior Aerospace MB-602 Metal Bellows (Met-Bel) pump. A second alternative is the hermetically sealed Edwards Vacuum nXDS15iC Scroll Pump. The Edwards scroll pump is potentially a less expensive alternative to the Met-Bel pumps, but it is unknown if this scroll pumps will survive a DBA accident and remain operational. In order to determine the electrical feedthrough in-leakage and the candidate pumps’ survivability, a seismic test was performed to simulate a DBA earthquake. This report summarizes the results of seismic test, including helium leak rates and functionality tests for the electrical feedthroughs and vacuum pumps. All components had pre- and post-test leak rates less than the threshold valve of 1x10 -6 scc per sec.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Microseismic Monitoring Study to Assess the Potential for Induced Seismicity in a Depleted Oil Field in Northern Michigan

The Midwest Regional Carbon Sequestration Partnership (MRCSP) was founded in 2003 as part of the U.S. Department of Energy’s (DOE’s) Regional Carbon Sequestration Partnership initiative. Since its founding, MRCSP has made significant strides toward making CCUS a viable option for states in the region. The public/private consortium, funded through the DOE Regional Carbon Sequestration Initiative, brings together nearly 40 industry partners and 10 states. Battelle, as the project lead, oversees research, development and operations and coordinates activities among the partners. The incremental, phased approach has built a valuable knowledge base for the industry and paved the way for commercial-scale adoption of CCUS technologies. From 2008 to 2020, MRCSP Phase III focused on the development of large-scale injection projects. This report is part of a series of reports prepared under the Midwestern Regional Carbon Sequestration Partnership (MRCSP) Phase III (Development Phase). These reports summarize and detail the findings of the work conducted under the Phase III project. Microseismic monitoring is the passive recording of very small-scale seismic energy events occurring underground. Microseismic monitoring has been proposed as a monitoring technology for CCUS sites to monitor fracturing before it becomes sufficiently extensive to cause leakage. This study aimed to determine if CO 2 injection into the Niagaran pinnacle reefs in northern Michigan is likely to generate microseismic events. The Niagaran reefs are relatively small, closed features making it possible to observe a large pressure increase by injecting a relatively small volume of CO 2 . In this study, two microseismic monitoring events were conducted 39 months apart during re-pressurization of the Dover 33 reef to evaluate the potential for CO 2 -injection induced seismicity in Silurian-age carbonate reef depleted oil reservoirs.

01 COAL, LIGNITE, AND PEAT↗

Cross-Well Seismic Monitoring of CO 2 Injected Into the A-1 Carbonate and Brown Niagaran Formations at the Chester 16 Reef

The Midwest Regional Carbon Sequestration Partnership (MRCSP) was founded in 2003 as part of the U.S. Department of Energy’s (DOE’s) Regional Carbon Sequestration Partnership initiative. Since its founding, MRCSP has made significant strides toward making CCUS a viable option for states in the region. The public/private consortium, funded through the DOE Regional Carbon Sequestration Initiative, brings together nearly 40 industry partners and 10 states. Battelle, as the project lead, oversees research, development and operations and coordinates activities among the partners. The incremental, phased approach has built a valuable knowledge base for the industry and paved the way for commercial-scale adoption of CCUS technologies. From 2008 to 2020, MRCSP Phase III focused on the development of large-scale injection projects. This report is part of a series of reports prepared under the Midwestern Regional Carbon Sequestration Partnership (MRCSP) Phase III (Development Phase). These reports summarize and detail the findings of the work conducted under the Phase III project. A cross-well seismic survey was acquired in the Chester 16 reef to attempt to locate 85,000 tonnes of carbon dioxide (CO 2 ) that were injected into the A-1 Carbonate and Brown Niagaran Formations earlier. The technique of conducting multiple cross-well seismic surveys over time, including a pre-CO 2 injection (baseline) survey, has been used elsewhere to monitor CO 2 injected into the subsurface. In this study, a baseline cross-well survey was not obtained; nevertheless, it was possible to generate an image that is a plausible representation of the CO 2 plume. This conclusion is supported by other monitoring and modeling results from the Chester 16 reef that provide an independent indication about the likely position of the injected CO 2 .

01 COAL, LIGNITE, AND PEAT↗

Seismic Bracing Development for the Moore 3 Diamond Turning Machine at Lawrence Livermore National Laboratory

To allow for on-site Potassium Dihydrogen Phosphate (KDP) crystal finishing capabilities, Lawrence Livermore National Laboratory (LLNL) acquired the Moore 3 diamond turning machine. Equipment such as the Moore 3 is required by LLNL to have adequate seismic bracing before permanent installation to reduce the risk of personnel injury or machine damage during an earthquake. The purpose of this project was to design a bracket that can withstand seismic forces induced by the machine without hindering function. To develop a solution, background research—including stakeholder identification, stakeholder interviews, and a literature survey—was conducted. Based on LLNL site and stakeholder requirements, several approaches were developed for bracing the Moore 3. Ideations were evaluated based on a weighted decision matrix and a final design strategy was selected. This design was an L-shaped weldment that featured provisions for four HILTI concrete anchors, three triangular gussets, and a steel construction.

42 ENGINEERING↗

ECAR-6601 MARVEL Project Seismic Accelerations

The MARVEL reactor design requirements are currently listed within TFR-2576. Several MARVEL subsystems are required to be designed to seismic criteria of IBC 2015. This Engineering Analysis (EA) report documents the accelerations that need to be used in an equivalent-static method seismic analysis to satisfy this requirement.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Wavelet Compression of Seismic Data

While wavelet transforms have been used in the analysis of seismic signals, the methods used for the compression of seismic signals have been limited to Linear Predictive Coding and Transform Coding.

wavelet compression seismic data linear predictive↗

The 26 December 2004 tsunami source estimated from satellite radar altimetry and seismic waves

The 26 December 2004 Indian Ocean tsunami was the first earthquake tsunami of its magnitude to occur since the advent of both digital seismometry and satellite radar altimetry. Both have independently recorded the event from different physical aspects. The seismic data has then been used to estimate the earthquake fault parameters, and a three-dimensional ocean-general-circulation-model (OGCM) coupled with the fault information has been used to simulate the satellite-observed tsunami waves. Here we show that these two datasets consistently provide the tsunami source using independent methodologies of seismic waveform inversion and ocean modeling. Cross-examining the two independent results confirms that the slip function is the most important condition controlling the tsunami strength, while the geometry and the rupture velocity of the tectonic plane determine the spatial patterns of the tsunami.

ocean general circulation model (OGCM)↗

Mass Wasting in Planetary Environments: Implications for Seismicity

On Earth, mass wasting events such as rock falls and landslides are well known consequences of seismic activity. Here we investigate the regional effects of seismicity in planetary environments with the goal of determining whether such surface features on the Moon, Mars, and Mercury could be triggered by fault motion.

seismicity↗

SEG Advances in Rotational Seismic Measurements

Significant advancements in the development of sensors to enable rotational seismic measurements have been achieved. Prototypes are available now to support experiments that help validate the utility of rotational seismic measurements.

15 GEOTHERMAL ENERGY↗

INDUCED MICROEARTHQUAKES AND SEISMICITY-PERMEABILITY RELATIONSHIPS IN FRACTURES

In the past several years, induced microearthquakes (MEQs) related to energy development projects have garnered public attention. Large-scale fluid injection in geoengineering activities, such as enhanced geothermal reservoir stimulation, geological storage of CO2, shale reservoir stimulation, and deep disposal of wastewater can generate significant fluid overpressures and induce microearthquakes by reactivating preexisting faults and fractures that are widely distributed throughout the upper crust. The monitoring of fluid-injection-induced microearthquakes can provide significant information (e.g., timing, special distribution, and moment magnitude) in evaluating reservoir development (e.g., fracture distribution and reservoir hydraulic conductivity evolution), in informing production strategies (e.g., accommodation of production wells), and in assessing the risks of fluid injection activities (e.g., caprock integrity of CO2 reservoir). The following questions are addressed in this study: (1) what are the mechanisms and implications of in-situ feedbacks (e.g., monitored fluid-injection-induced MEQs distribution, seismic moment magnitudes, and fracture behaviors) in geothermal stimulation? (2) What information can be derived from MEQs to inform geothermal reservoir stimulation strategies? (3) Are there any potential relationships between induced seismic or aseismic slip and permeability evolution of fractures in such unconventional reservoirs and caprocks? (4) What factors play an important role in controlling these relationships? These questions are addressed in the five individual chapters of this thesis.

58 GEOSCIENCES↗

AP1000{sup R} design robustness against extreme external events - Seismic, flooding, and aircraft crash

Both the International Atomic Energy Agency (IAEA) and the U.S. Nuclear Regulatory Commission (NRC) require existing and new nuclear power plants to conduct plant assessments to demonstrate the unit's ability to withstand external hazards. The events that occurred at the Fukushima-Dai-ichi nuclear power station demonstrated the importance of designing a nuclear power plant with the ability to protect the plant against extreme external hazards. The innovative design of the AP1000{sup R} nuclear power plant provides unparalleled protection against catastrophic external events which can lead to extensive infrastructure damage and place the plant in an extended abnormal situation. The AP1000 plant is an 1100-MWe pressurized water reactor with passive safety features and extensive plant simplifications that enhance construction, operation, maintenance and safety. The plant's compact safety related footprint and protection provided by its robust nuclear island structures prevent significant damage to systems, structures, and components required to safely shutdown the plant and maintain core and spent fuel pool cooling and containment integrity following extreme external events. The AP1000 nuclear power plant has been extensively analyzed and reviewed to demonstrate that it's nuclear island design and plant layout provide protection against both design basis and extreme beyond design basis external hazards such as extreme seismic events, external flooding that exceeds the maximum probable flood limit, and malicious aircraft impact. The AP1000 nuclear power plant uses fail safe passive features to mitigate design basis accidents. The passive safety systems are designed to function without safety-grade support systems (such as AC power, component cooling water, service water, compressed air or HVAC). The plant has been designed to protect systems, structures, and components critical to placing the reactor in a safe shutdown condition within the steel containment vessel which is further surrounded by a substantial 'steel concrete' composite shield building. The containment vessel is not affected by external flooding, and the shield building design provides hazard protection beyond that provided by a comparable reinforced concrete structure. The intent of this paper is to demonstrate the robustness of the AP1000 design against extreme events. The paper will focus on the plants ability to withstand extreme external events such as beyond design basis flooding, seismic events, and malicious aircraft impact. The paper will highlight the robustness of the AP1000 nuclear island design including the protection provided by the unique AP1000 composite shield building. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Seismic Resilience of Large Power Transformer Bushings & Non-SF6 Industrial Base Scan Review

Large (high voltage) power transformers (LPT), and more specifically, their bushings, are known to be susceptible to seismic failure. With bushing failure, a transformer will have to be replaced, which has a considerable lead time, adding to the power outage duration. Cost-efficient, proven solutions are not currently available to mitigate this risk, which can persist for the more than 30-year life of a particular transformer. This work will focus on developing and demonstrating a hardware solution to address seismic vulnerabilities and reduce outage risks from LPT failure. Sulfur Hexafluoride (SF6) is a specialty gas with excellent electrical insulation properties which has been used extensively in the power industry. This gas is unfortunately also one of the most potent greenhouse gases known to humanity. A 2014 report by the Intergovernmental Panel on Climate Change found that SF6 has a global warming potential (GWP) 23,000 times higher than Carbon Dioxide, and has the highest GWP of all gases assessed (Myhre 2013). SF6 is almost exclusively man-made and is produced for use as an insulator in high voltage electrical equipment. This makes the production and use of SF6 one of the leading sources of anthropogenic climate change. To fully eliminate the environmental impacts of SF6, alternative technology is needed. The ideal replacement would be a technology that can fulfil the same role as SF6, at the same cost or cheaper, but without adverse environmental effects. Currently, no technology fits this description, however several promising technologies have begun to enter the market. An industry scan was performed to assess the state of industry adoption and manufacturing capability for SF6-free alternative technologies for use at the high-voltage level, and the primary barriers to broader adoption.

10 SYNTHETIC FUELS↗

ECAR-6601 Rev 1 MARVEL Project Seismic Accelerations

The MARVEL reactor design requirements are currently listed within TFR-2576. Several MARVEL subsystems are required to be designed to seismic criteria of IBC 2015. This Engineering Analysis (EA) report documents the accelerations that need to be used in an equivalent-static method seismic analysis to satisfy this requirement.

21 - SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLAN↗

Utah FORGE: Seismic Reflection Data

This is 2D and 3D seismic reflection data from Utah FORGE reprocessed during Phase 2c. The readme file containing an explanation of the data including data formats, software that can be used, processing, and projection and datum used. The Reprocessing document gives the rationale for reprocessing and shows examples of the improvements that were obtained. For all 3D and 2D data the following datasets were created and output in SEG-Y format: - Unmigrated Time - Prestack Time Migration (PSTM), Unenhanced (UnEnh) and Enhanced (Enh) - Prestack Depth Migration (PSDM), Unenhanced (UnEnh) and Enhanced (Enh) - Velocity Model used for Migration

15 GEOTHERMAL ENERGY↗