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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 253 records · Page 14
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Closure Report for the Central Facilities Area Sewage Treatment Plant Lagoon 3 and Land Application Area

Because of significantly reduced wastewater discharges to the Central Facilities Area Sewage Treatment Plant, wastewater has not been land applied since 2011. The future need to land apply wastewater was evaluated. Based on the current wastewater flows into the Central Facilities Area Sewage Treatment Plant, expected future missions at Central Facilities Area, and the discovery in 2014 that Lagoon 3 was leaking at an unacceptable rate, it was determined that the Central Facilities Area Sewage Treatment Plant is significantly oversized and that Lagoons 1 and 2 could be converted to total evaporation lagoons. Therefore, the decision was made to remove the existing sludge in Lagoon 3 and transfer it to Lagoon 2 for additional treatment, decommission Lagoon 3 and the land application area, and terminate the wastewater reuse permit. A closure plan was submitted and approved by the Idaho Department of Environmental Quality in 2016. This report describes the closure activities that were performed. Closure activities included: • Characterizing the soil/liner in Lagoon 3 to determine whether further characterization and/or remediation will be required under the Comprehensive Environmental Response, Compensation, and Liability Act. • Based on the results from the soil/liner sampling, determining whether additional sampling will be required for the land application area. • Removing the sludge in Lagoon 3 and placing it in Lagoon 2. • Puncturing the Lagoon 3 soil/liner to prevent ponding of storm water and becoming a source for vectors. • Installing a permanent cap on the inlet piping to Lagoon 3. Samples were collected on November 10, 2016, and were submitted for analysis to an off-site laboratory. Data validation and evaluation were performed by Portage, INC. Sample results confirmed that there is no hazard to human health and the environment and that Lagoon 3 and the land application area could be closed. In August 2017, sludge was removed from Lagoon 3 and placed in Lagoon 2, the soil/liner was punctured in 4 places, and caps were installed on the primary and bypass inlet lines.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2018

Closure Plan for the Idaho National Laboratory Site's Materials and Fuels Complex Industrial Waste Ditch

The Materials and Fuels Complex industrial waste system currently consists of the Industrial Waste Pond and Industrial Waste Ditch, associated piping, lift station, and flow meter. The Industrial Waste Pond and Industrial Waste Ditch, are land application sites permitted under Idaho Department of Environmental Quality Reuse Permit I-160-02, Modification 1. The Reuse Permit allows for 17 million gallons of industrial wastewater to be discharged to the land application sites. For Reuse Permit year 2017, approximately 7.569 million gallons were discharged to the land application sites, of which 1.649 million gallons were discharged to the Industrial Waste Ditch. A project (MFC West Campus Utility Corridor project) is proposed to begin in the summer of 2018. The project will install a new utility corridor along the west and north sides of the Materials and Fuels Complex. As part of the design, it is proposed to reroute the wastewater currently discharged to the Industrial Waste Ditch into an underground pipe that would connect into the existing Industrial Waste Pipeline. The Industrial Waste Ditch pipe would enter the existing Industrial Waste Pipeline upstream of the existing flow meter and sampling location. This would allow for the combined wastewater streams to be monitored for flow and sampled for parameters required by the Reuse Permit. In accordance with the Reuse Permit, this closure plan is being submitted to the Idaho Department of Environmental Quality for review and approval. Once the closure plan is approved, the Reuse Permit will be modified to remove the Industrial Waste Ditch from the permit. The closure plan includes: • Brief background of the Materials and Fuels Complex. • Reuse Permit history. • Site characteristics. • Description of the Industrial Wastewater System. • History of discharges to the Industrial Waste Ditch. • Summary of the Comprehensive Environmental Response, Compensation, and Liability Act characterization, evaluation, and remediation of the Industrial Waste Ditch. • Contaminant concentrations in the effluent discharged to the Industrial Waste Ditch. • Contaminant concentrations in cross gradient, downgradient, and background monitoring wells. Based on the Comprehensive Environmental Response, Compensation, and Liability Act characterization and remediation of the Industrial Waste Ditch, low volumes and contaminant concentrations in the effluent subsequently discharged to the Industrial Waste Ditch, and contaminant concentrations at or near background levels in the monitoring wells, it is recommended that the Industrial Waste Ditch should be closed without further characterization.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2019

Post-Closure Report for Closed Resource Conservation and Recovery Act Corrective Action Units, Nevada National Security Site, Nevada: For Calendar Year 2018 (Revision 0)

This report serves as the combined annual report for post-closure activities for the following closed corrective action units (CAUs): CAU 90, Area 2 Bitcutter Containment; CAU 91, Area 3 U-3fi Injection Well; CAU 92, Area 6 Decon Pond Facility; CAU 110, Area 3 WMD U-3ax/bl Crater; CAU 111, Area 5 WMD Retired Mixed Waste Pits; and CAU 112, Area 23 Hazardous Waste Trenches. The locations of the sites are shown in Figure ES-1. This report covers calender year 2018. The post-closure requirements for these sites are described in Resource Conservation and Recovery Act Permit Number NEV HW0101 and are summarized in each CAU-specific section of this report. The results of the inspections, a summary of maintenance activities, and an evaluation of monitoring data are presented in this report. Site inspections are conducted annually at CAUs 90, 91, and 112; semiannually at CAUs 92 and 110; and quarterly at CAU 111. Additional inspections are conducted at CAUs 92 and 111 if precipitation occurs in excess of 1.0 inch in a 24-hour period. Inspections include an evaluation of the condition of the units, including covers, fences, signs, gates, and locks. At CAUs 110 and 111, soil moisture monitoring and subsidence surveys are conducted in addition to the visual inspections. At CAU 110 the site fence, gate, lock and use restriction signs are evaluated. At CAU 111, an ecological survey, direct radiation monitoring, air monitoring, radon flux monitoring, and groundwater monitoring are also conducted. This report will address all monitoring item notes above except groundwater monitoring. Groundwater monitoring is documented in the Nevada National Security Site Data Report: Groundwater Monitoring Program Area 5 Radioactive Waste Management Site. All required inspections, maintenance, and monitoring were conducted in accordance with the post-closure requirements of the permit. Revision 6 of Permit NEV HW0101 was issued effective December 10, 2015, and remains in effect until December 10, 2020.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

Closure and transport theory for plasmas with multiple ion species

This report summarizes a DOE-funded research project on closure and transport theory for plasmas with multiple ion species. The work developed accurate moment-based closure models across the full range of collisionality, incorporating both kinetic and collisional effects. Key contributions include high-fidelity closure relations, multi-temperature models, and transport coefficients applicable to fusion, space, and astrophysical plasmas.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2025

Closure Report for Corrective Action Unit 366: Area 11 Plutonium Valley Dispersion Sites, Nevada National Security Site, Nevada with ROTC 1

This Closure Report presents information supporting closure of Corrective Action Unit (CAU) 366, Area 11 Plutonium Valley Dispersion Sites, and provides documentation supporting the completed corrective actions and confirmation that closure objectives for CAU 366 were met. CAU 366 consists of the following six Corrective Action Sites (CASs), located in Area 11 of the Nevada National Security Site: • CAS 11-08-01, Contaminated Waste Dump #1 • CAS 11-08-02, Contaminated Waste Dump #2 • CAS 11-23-01, Radioactively Contaminated Area A • CAS 11-23-02, Radioactively Contaminated Area B • CAS 11-23-03, Radioactively Contaminated Area C • CAS 11-23-04, Radioactively Contaminated Area D

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS2017

Life Support Goals Including High Closure and Low Mass Should Be Reconsidered Using Systems Analysis

Recycling space life support systems have been built and tested since the 1960s and have operated on the International Space Station (ISS) since the mid 2000s. The development of space life support has been guided by a general consensus focused on two important related goals, increasing system closure and reducing launch mass. High closure is achieved by recycling crew waste products such as carbon dioxide and condensed humidity. Recycling directly reduces the mass of oxygen and water for the crew that must be launched from Earth. The launch mass of life support can be further reduced by developing recycling systems with lower hardware mass and reduced power. The life support consensus has also favored using biological systems. The goal of increasing closure using biological systems suggests that food should be grown in space and that biological processors be used for air, water, and waste recycling. The goal of reducing launch mass led to use of Equivalent System Mass (ESM) in life support advocacy and technology selection. The recent consensus assumes that the recycling systems architecture developed in the 1960s and implemented on ISS will be used on all future long missions. NASA and other project organizations use the standard systems engineering process to guide hardware development. The systems process was used to develop ISS life support, but it has been less emphasized in planning future systems for the moon and Mars. Since such missions are far in the future, there has been less immediate need for systems engineering analysis to consider trade-offs, reliability, and Life Cycle Cost (LCC). Preliminary systems analysis suggests that the life support consensus concepts should be revised to reflect systems engineering requirements.

systems analysis↗
DOE OSTI2020

Achievements and Ongoing Challenges for advanced CFD Boiling Closure Model Development using Physical Insights from Validation-Oriented High-Fidelity Boiling Experiment

The fundamental understanding of the boiling-associated heat transfer, including sliding bubble effect, is still challenging despite the intensive research for decades in both experimental and computational boiling research communities. One of the main difficulties of boiling experiment come from the fact that direct observation of the underlying principle through experiment is very difficult due to the high complexity of the boiling phenomenon. Also, since the heat transfer characteristics associated with boiling is the result of non-linear interaction of various physical parameters coupled to each other, it is challenging to find the relationship between the parameters for modeling. This paper discusses the authors’ past and ongoing boiling research under CASL (Consortium for Advanced Simulation of Light Water Reactors) program, including the efforts to overcome the difficulties of boiling measurement and model development. In particular, we focus on describing the major achievements, lessons learnt, and ongoing challenges for the CFD boiling closure model development based on the high-fidelity subcooled flow boiling experiment at Texas A&M University (TAMU). The major research achievements discussed through this paper include (i) novel boiling measurement strategy and high-fidelity validation data production, (ii) dedicated effort to identify the critical measurement issues in boiling experiment, (iii) new physical insight into sliding bubble heat transfer mechanisms, and (iv) new boiling closure model development. Discussion is also made on the ongoing challenges for the boiling closure model development and the future research plan based on the lessons learnt.

42 ENGINEERING↗
DOE OSTI2013

Applying Lean Concepts to Waste Site Closure - 13137

Washington Closure Hanford (WCH) was selected by the U.S. Department of Energy, Richland Operations Office to manage the River Corridor Closure Project, a 10-year contract in which WCH will clean up 220 mi{sup 2} of contaminated land at the Hanford Site in Richland, Washington. In the summer of 2011, with Tri-Party (DOE-RL, Environmental Protection Agency and Washington State Department of Ecology) Agreement Milestones due at the end of the calendar year, standard work practices were challenged in regards to closure documentation development. The Lean process, a concept that maximizes customer value while minimizing waste, was introduced to WCH's Sample Design and Cleanup Verification organization with the intention of eliminating waste and maximizing efficiencies. The outcome of implementing Lean processes and concepts was impressive. It was determined that the number of non-value added steps far outnumbered the value added steps. Internal processing time, document size, and review times were all reduced significantly; relationships with the customer and the regulators were also improved; and collaborative working relationships with the Tri Parties have been strengthened by working together on Lean initiatives. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2013

Observation and Responses to Post-Closure Instances of Localized Instability and Subsidence at the DOE Legacy Management Rocky Flats Site, Colorado-13052

The former Rocky Flats Plant in Colorado began operations as part of the nation's nuclear weapons complex in the early 1950's. By the 1980's the associated heavily industrialized area covered approximately 1.2 km{sup 2} (300 acres) and was surrounded by an approximately 25.3 km{sup 2} (6,245 acre) security buffer zone. The federally owned property and adjacent offsite areas were placed on the CERCLA National Priority List in 1989. To complete closure, all buildings and other structures that composed the Rocky Flats industrial complex were removed from the surface, but remnants remain in the subsurface. Contouring and grading to return the surface to approximate conditions that were present prior to the plant's construction was completed in 2005. A goal of the final land configuration was to provide long-term surface and subsurface land stability. Several instances of localized surface subsidence or instability have occurred since the final configuration. The localized nature and the relatively small areas of observed subsidence and instability indicate that, overall, the final configuration is performing well, but responses to these occurrences and the observations that followed may be useful in planning for the closure and designing the final land configuration and post-closure monitoring at other sites. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Status Update on TRAC: A DOE-EM Tool for Tracking Groundwater Cleanup and Progress Toward Site Closure - 20245

The U.S. Department of Energy (DOE) Office of Environmental Management (EM) uses a customized, web-based mapping tool called TRAC (Tracking Restoration and Closure) to communicate information on plume sizes, remedial approaches, regulatory drivers, exit strategies, and long-term stewardship requirements at all sites within the DOE-EM complex. The web-based GIS story maps provide robust geospatial visualization of plumes at DOE sites using an intuitive interface that allows users to explore the plume maps, explanatory text, photographs, and video. This collection of story maps not only communicates information for each individual site, but also summarizes pertinent metrics on cleanup and remaining contaminants across all EM sites. This paper describes a new design within TRAC for communicating metrics on plume status, regulatory cleanup progress, and technology implementation. A principal benefit of TRAC is the ability to view individual pieces of data at a time, permitting targeted questions to be addressed, such as the status of regulatory decisions, site cleanup priorities, and site closure needs for each site within the DOE-EM complex. TRAC manages communication and supports decision-making through knowledge access, data and information transparency and traceability, and inclusive participation. It serves as a common resource that provides consistent information for DOE managers, site personnel, regulators and stakeholders. Because long-term stewardship of legacy waste sites requires ongoing coordination and communication among DOE, regulators, and stakeholders, TRAC can also be used to help transition EM sites to the Office of Legacy Management at site closure. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Panel Session 46: Final Closure of Unlined LLW Disposal Facilities Worldwide (R3.5)

This panel discussed the on-going and emerging issues with the design and construction of final cover system of unlined disposal facilities (e.g., material disposal areas (MDAs), subsurface disposal areas (SDAs), burial grounds, and similar historical waste trenches, pits and vaults). The discussion focused on key technical and regulatory issues as well as lessons learned from years of engineering and construction in US and non-US locations. Panelists with presentations: Closure of Unlined LLW Disposal Sites (Craig Benson); Closure of LLW Facilities (Paul Pointon); Final Closure of Unlined LLW Disposal Facilities - Lessons Learned (Kevin Foye)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2025

Modeling hydraulic fracture opening and closure with proppant transport and settlement

Hydraulic fracturing is a widely used reservoir stimulation technique for improving fluid circulation in rock formations with extremely low permeability, particularly in enhanced geothermal systems (EGS). To better understand the complex processes involved and improve hydraulic stimulation performance, we have developed ELK (ELectrical fracKing), a MOOSE-based 3D finite element application designed to model the behavior of proppant-fluid mixtures in propagating fractures. ELK integrates both the fluid and proppant components, incorporating particle-driven processes such as gravity settling, particle-particle interactions, and strong density and viscosity contracts, in addition to conventional fluid-driven fracture propagation. In this contribution, we extend ELK to model propped fracture closure, which occurs after the injection phase due to a dramatic drop in the effective stress on the fracture plane. During the shut-in, flowback, and production periods, the fracture width decreases, with the closure behavior depending on proppant concentration.. At low concentrations, closure follows a nonlinear joint law linked to the stiffness of asperities in the fracture walls. While at high concentrations, it is controlled by the properties of packed proppant bed. The extended ELK application is validated against several benchmark examples, including the propagation of an inclined frictional crack, fracture opening and sliding in response to fluid injection, and flowback analysis. We believe that ELK’s enhanced capabilities can serve as a valuable tool for the design and optimization of EGS deployment.

15 - GEOTHERMAL ENERGY↗
DOE OSTI2012

Obesity: An Independent Risk Factor for Insufficient Hemostasis Using the AngioSeal Vascular Closure Device After Antegrade Puncture

Purpose: This study was designed to investigate the efficacy of the AngioSeal vascular closure device after antegrade puncture of the femoral artery. Methods: In a prospective study, 120 consecutive patients underwent lower limb vascular intervention by an antegrade access to the common femoral artery (CFA). After intervention, a 6F (n = 88) or an 8F (n = 32) AngioSeal vascular closure device was used to achieve hemostasis. The technical success or the cause of failure was documented. In addition, the coagulation status (platelets, INR, prothrombin time, atrial thromboplastin time (PTT)), hypertonus, locoregional habitus of the groin, body mass index (BMI), presence of calcifications, and history of previous surgical interventions of the CFA were evaluated. Results: Hemostasis was achieved in 97 patients (81%). In 12 patients (10%), persistent bleeding of the puncture site required manual compression. In another nine patients (8%) a kink of the sheath obviated the passage of the collagen plug toward the vessel, and in two patients the anchor dislodged out of the vessel, requiring manual compression. There were no significant differences between the groups of successful and unsuccessful sealing regarding the mean platelets (241 vs. 254 * 10{sup 9}/l; P = 0.86), INR (1.06 vs. 1.02; P = 0.52), prothrombin time (90% vs. 90%; P = 0.86), and PTT (30 vs. 31 s; P = 0.82). However, unsuccessful sealing was more likely in obese patients with an increased BMI (26.6 vs. 28.8 kg/m{sup 2}; P = 0.04). Conclusions: Obesity seems to be an independent risk factor for insufficient sealing using the AngioSeal vascular closure device after antegrade puncture of the CFA. In 8% of our patients, hemostasis could not be achieved due to kink of the flexible sheath.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Optimization and large scale computation of an entropy-based moment closure

We present computational advances and results in the implementation of an entropy-based moment closure, M N , in the context of linear kinetic equations, with an emphasis on heterogeneous and large-scale computing platforms. Entropy-based closures are known in several cases to yield more accurate results than closures based on standard spectral approximations, such as P N , but the computational cost is generally much higher and often prohibitive. Several optimizations are introduced to improve the performance of entropy-based algorithms over previous implementations. These optimizations include the use of GPU acceleration and the exploitation of the mathematical properties of spherical harmonics, which are used as test functions in the moment formulation. To test the emerging high-performance computing paradigm of communication bound simulations, we present timing results at the largest computational scales currently available. Lastly, these results show, in particular, load balancing issues in scaling the M N algorithm that do not appear for the P N algorithm. We also observe that in weak scaling tests, the ratio in time to solution of M N to P N decreases.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2017

Simulations of anti-parallel reconnection using a nonlocal heat flux closure

The integration of kinetic effects in fluid models is important for global simulations of the Earth's magnetosphere. In particular, it has been shown that ion kinetics play a crucial role in the dynamics of large reconnecting systems, and that higher-order fluid moment models can account for some of these effects. Here, we use a ten-moment model for electrons and ions, which includes the off diagonal elements of the pressure tensor that are important for magnetic reconnection. Kinetic effects are recovered by using a nonlocal heat flux closure, which approximates linear Landau damping in the fluid framework. Moreover, the closure is tested using the island coalescence problem, which is sensitive to ion dynamics. We also demonstrate that the nonlocal closure is able to self-consistently reproduce the structure of the ion diffusion region, pressure tensor, and ion velocity without the need for fine-tuning of relaxation coefficients present in earlier models.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2020

An improved ten-moment closure for reconnection and instabilities

The integration of kinetic effects in fluid models is important for global simulations of Earth's magnetosphere. The use of the two-fluid ten-moment model, which includes the pressure tensor for both species, has had some success in simulating Ganymede and Mercury with a simple closure model. Here, we discuss a heat flux closure which accounts for some limitations of the earlier work while remaining computationally tractable. Comparisons with kinetic simulations for magnetic reconnection and lower-hybrid drift instabilities show good agreement with kinetic results and improvements on previous closure models.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2023

Differentiable physics-enabled closure modeling for Burgers’ turbulence

Abstract Data-driven turbulence modeling is experiencing a surge in interest following algorithmic and hardware developments in the data sciences. We discuss an approach using the differentiable physics paradigm that combines known physics with machine learning to develop closure models for Burgers’ turbulence. We consider the one-dimensional Burgers system as a prototypical test problem for modeling the unresolved terms in advection-dominated turbulence problems. We train a series of models that incorporate varying degrees of physical assumptions on an a posteriori loss function to test the efficacy of models across a range of system parameters, including viscosity, time, and grid resolution. We find that constraining models with inductive biases in the form of partial differential equations that contain known physics or existing closure approaches produces highly data-efficient, accurate, and generalizable models, outperforming state-of-the-art baselines. Addition of structure in the form of physics information also brings a level of interpretability to the models, potentially offering a stepping stone to the future of closure modeling.

97 MATHEMATICS AND COMPUTING↗