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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 883 records · Page 49
All sourcesNASA NTRSDOE OSTI
NASA NTRS2017

Modelling the Risks Remotely Piloted Aircraft Pose to People on the Ground

Worldwide there is much e ort being directed towards the development of a framework of air- worthiness regulations for remotely piloted aircraft systems (RPAS). It is now broadly accepted that regulations should have a strong foundation in, and traceability to, the management of the safety risks. Existing risk models for RPAS operations do not provide a simple means for incorporating the wide range of technical and operational controls into the risk analysis and evaluation processes. This paper describes a new approach for modelling and evaluating the risks associated with RPAS operations near populous areas based on the barrier bow tie (BBT) model. A BBT model is used to structure the underlying risk management problem. The model focuses risk analysis, evaluation, and decision making activities on the devices, people, and processes that can be employed to reduce risk. The BBT model and a comprehensive set of example risk controls are presented. The general model can be applied to any RPAS operation. The foundations for quantitative and qualitative assessments using a BBT model are also presented. The modelling and evaluation framework is illustrated through its application to a case-study rotary wing RPAS for two operational scenarios. The model can be used as a basis for determining airworthiness certification requirements for RPAS.

Barrier bow tie model↗
DOE OSTI2020

AGR-3/4 PIE at Oak Ridge National Laboratory

The Idaho National Laboratory (INL) Advanced Reactor Technologies (ART) is currently supporting a tristructural isotropic (TRISO) fuel development and qualification program, which includes fuel fabrication, test irradiations, and post-irradiation examination (PIE) and safety testing to assess fuel performance during normal irradiation and under accident conditions. PIE work on fuel from the third and fourth test irradiations, Advanced Gas Reactor-3/4 (AGR-3/4), began at INL in April 2015. The work scope in this memorandum purchase order (MPO) includes Oak Ridge National Laboratory (ORNL) providing technical input, preparations for PIE testing and analysis, and contributing general expertise to this effort.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2018

AGR-3/4 PIE at Oak Ridge National Laboratory

The Idaho National Laboratory (INL) Advanced Reactor Technologies (ART) is currently supporting a tristructural isotropic (TRISO) fuel development and qualification program, which includes fuel fabrication, test irradiations, and post-irradiation examination (PIE) and safety testing to assess fuel performance during normal irradiation and under accident conditions. PIE work on fuel from the third and fourth test irradiations, Advanced Gas Reactor-3/4 (AGR-3/4), began at INL in April 2015. The work scope in this memorandum purchase order (MPO) includes Oak Ridge National Laboratory (ORNL) providing technical input, preparations for PIE testing and analysis, and contributing general expertise to this effort.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2023

Guiding Sustainable Hydrogen Integration: A Capacity Building Approach

The Hydrogen Considerations Tree is designed to empower institutions to explore and consider the costs, benefits, and tradeoffs of hydrogen and its derivatives (e.g. e-fuels and green ammonia) and inform hydrogen strategy, policy and investment decisions within unique contexts around the world. Key topics are organized into a "Considerations Tree," enabling stakeholders to explore technical, regulatory, economic, environmental, social, and other analysis questions systematically and holistically.

HYDROGEN↗
DOE OSTI2019

Histologic Analysis with the Newly Designed Exoskeleton Seal{sup ®} Stent-Graft in the Porcine Abdominal Aorta

Purpose: To investigate the technical feasibility of a novel exoskeleton Seal{sup ®} stent-graft and analyze early histologic changes in the porcine abdominal aorta. Materials and Methods: Six pigs received an abdominal stent-graft (Group I), and six received an iliac branch stent-graft (Group II). Groups were subdivided as follows: Group Ia, which received three bifurcated main-body stent-grafts; Group Ib, which received three bifurcated main-body stent-grafts with both iliac graft-stents; Group IIa, which received three simple uni-iliac tapered stent-grafts; and Group IIb, which received three uni-iliac tapered tapered stent-grafts with right straight limb and left branched limb. Statistical analyses were performed with the Wilcoxon signed-rank test and mixed-model regression analysis. Results: The primary technical success rate (< 24 h) was 83% because of two acute thromboses in the lumen of the stented abdominal aorta immediately after stent-graft placement. At 4 weeks, late thrombosis occurred in two pigs. Higher mean neointimal hyperplasia areas (23.5% vs. 16.2%; P = .047), neointimal hyperplasia thicknesses (545.5 μm vs. 422.2 μm; P = .001), and degrees of collagen deposition (2.71 vs. 2.33; P = .002) were observed at the bare-metal stent-graft compared with the proximal exoskeleton portion of the stent-graft, with no significant differences between the patent and occluded groups or among the four types of stent-grafts. Conclusions: The exoskeleton stent-graft demonstrates 66% of patency rate during 1-month follow-up due to four cases of thromboses; however, the endothelialization on the junction of proximal graft showed no significant differences between the patent and occluded groups. Further studies should investigate long-term outcomes with prolonged neointimal hyperplasia.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
NASA NTRS2024

Cost and Benefit Analysis of Mitigating, Tracking, and Remediating Orbital Debris

Presentation accompanying the technical report with the same name. The abstract for the report and the full study is repeated below. Orbital debris may collide with crewed and robotic spacecraft, placing them at risk. The wide range of debris, from 9,000-kilogram rocket bodies to millions of millimeter-size debris, has led to a similarly wide range of proposed actions for addressing the risks posed by debris. However, the costs and benefits of these actions have historically been unknown. This is a challenge for decision makers who are choosing which actions to support through technology development or policy changes. NASA’s Office of Technology, Policy, and Strategy is addressing these technical and economic uncertainties by building a capability to (1) complete rigorous calculations of the net present value of each action, (2) identify an optimal portfolio of actions to reduce risk, and (3) quantitatively analyze policies related to space sustainability. This report describes our progress toward that capability and to solicit feedback from the space and economic communities. Our previous work, referred to here as Phase 1, assessed the costs and benefits of performing debris remediation on operationally relevant timescales. The current analysis contains major updates to the risk model used in Phase 1 and expands the breadth of actions considered to include mitigating the creation of debris, improving the ability to track debris, and more methods for cleaning up existing debris. We demonstrate that our approach of measuring risks in dollars allows for the effectiveness of seemingly incommensurate actions to be compared and generates insights that other approaches to measuring risk have missed.

Jericho Locke↗
DOE OSTI2024

Offline Power Systems Applications Enabled by Phasor Measurement Units: Technical Assistance to the Power Sectors of Southeast Asia

This report provides a brief overview of several offline (non-real-time) applications facilitated by high-resolution time-synchronized measurements recorded by phasor measurement units (PMUs). The high reporting rate and time-synchronization of PMU records provide a detailed view of power system dynamics, enabling electric utilities to obtain a better understanding of their systems. In this report, the following applications have been reviewed: Power plant model validation, System model validation, Ringdown oscillation analysis, Frequency response analysis, Postmortem analysis of disturbance events Along with a brief technical background of the applications above, applicable North American Electric Reliability Corporation (NERC) standards have been discussed, and examples of implementation in North American organizations have been provided. Implementing several of the discussed applications may need a preliminary stage of data gathering from multiple entities, and several frameworks and process flows have been formulated by organizations around the world for this purpose. However, the data-gathering stage has not been considered in the scope of the present report.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2019

Utilizing FLEX Equipment for O&M Cost Reduction in Nuclear Power Plants

There are many ways of reducing the O&M costs; this work presents an innovative framework of reducing O&M costs by utilizing the onsite Flex equipment at NPPs. Flex strategies were postulated by the U.S. Nuclear Regulatory Commission (NRC) in the wake of Fukushima Dai-ichi accident to address beyond-design-basis accidents and improve plant flexibility. Onsite Flex includes equipment such as portable pumps, generators, batteries, compressors, and other supporting equipment or tools, all stored in a dedicated and secure building designed to withstand external hazards. In the past years, several NPPs have invested in procuring and maintaining the onsite Flex asset that stands unutilized most of the time. Recently there have been active efforts to develop strategies through which NPPs can take credit for the Flex equipment. This work focuses on identifying areas where Flex equipment can be utilized during normal plant operation and develop a framework that would aide in reduction of O&M costs without impacting plant safety. Earlier work in the current project, published in INL/EXT 18 51531, had presented the risk- and cost-analysis framework for utilizing FLEX portable equipment during technical specification required shutdown due to component failure. The licensee event report (LER) database of the NRC shows that the commercial NPPs in the US reported 86 technical specification required shutdowns since year 2010. When a component failure or unavailability leads to a technical specification required shutdown, the NPPs suffers both direct costs in terms of loss of revenue arising from the loss of generation and indirect costs in form of reporting and inspection required by the NRC. The earlier work developed the following framework and implemented it on a demonstration probabilistic risk assessment (PRA) model to utilize the portable Flex equipment when a component failure could potentially lead to a technical specification required shutdown: 1. Identify the components, the failure or unavailability of which would result in a 10 CFR 50.73(a)(2)(i)A-reportability requirement, postulated by the NRC for technical specification required shutdown to be reported in NRC’s LER database. 2. Identify the Flex equipment that can be utilized as a standby to the failed component. 3. Develop a probabilistic risk assessment (PRA) model that incorporates the Flex equipment within the current plant PRA model. 4. Perform PRA calculations to determine change in core damage frequency and change in risk-informed allowable outage time. 5. Perform cost-benefit analysis to determine the economic feasibility of implementing the Flex equipment The current work, presented in this report, implement the above framework in a plant PRA model obtained from a US commercial nuclear power plant by prestaging onsite FLEX equipment as a redundancy to the existing auxiliary feedwater system, and pre-coordinating with offsite FLEX centers. The new configuration increased the allowable outage time by about a fifty percent overall for the diesel generator being out of service. The benefits to NPPs of utilizing the Flex equipment during normal operations, and performing the PRA developed in this work, include: 1. A risk-informed plant shutdown alternative to the current technical specification required shutdown. 2. Extension of allowable outage time to initiate technical specification required shutdown. 3. Reducing economic impact of component failure, avoiding plant shutdown, and maximizing generation. 4. Save the direct and indirect costs associated with technical specification required shutdown.

42 ENGINEERING↗
NASA NTRS2010

NASA Supportability Engineering Implementation Utilizing DoD Practices and Processes

The Ares I design and development program made the determination early in the System Design Review Phase to utilize DoD ILS and LSA approach for supportability engineering as an integral part of the system engineering process. This paper is to provide a review of the overall approach to design Ares-I with an emphasis on a more affordable, supportable, and sustainable launch vehicle. Discussions will include the requirements development, design influence, support concept alternatives, ILS and LSA planning, Logistics support analyses/trades performed, LSA tailoring for NASA Ares Program, support system infrastructure identification, ILS Design Review documentation, Working Group coordination, and overall ILS implementation. At the outset, the Ares I Project initiated the development of the Integrated Logistics Support Plan (ILSP) and a Logistics Support Analysis process to provide a path forward for the management of the Ares-I ILS program and supportability analysis activities. The ILSP provide the initial planning and coordination between the Ares-I Project Elements and Ground Operation Project. The LSA process provided a system engineering approach in the development of the Ares-I supportability requirements; influence the design for supportability and development of alternative support concepts that satisfies the program operability requirements. The LSA planning and analysis results are documented in the Logistics Support Analysis Report. This document was required during the Ares-I System Design Review (SDR) and Preliminary Design Review (PDR) review cycles. To help coordinate the LSA process across the Ares-I project and between programs, the LSA Report is updated and released quarterly. A System Requirement Analysis was performed to determine the supportability requirements and technical performance measurements (TPMs). Two working groups were established to provide support in the management and implement the Ares-I ILS program, the Integrated Logistics Support Working Group (ILSWG) and the Logistics Support Analysis Record Working Group (LSARWG). The Ares I ILSWG is established to assess the requirements and conduct, evaluate analyses and trade studies associated with acquisition logistic and supportability processes and to resolve Ares I integrated logistics and supportability issues. It established a strategic collaborative alliance for coordination of Logistics Support Analysis activates in support of the integrated Ares I vehicle design and development of logistics support infrastructure. A Joint Ares I - Orion LSAR Working Group was established to: 1) Guide the development of Ares-I and Orion LSAR data and serve as a model for future Constellation programs, 2) Develop rules and assumptions that will apply across the Constellation program with regards to the program's LSAR development, and 3) Maintain the Constellation LSAR Style Guide.

Smith, David A.↗
NASA NTRS1978

Synthesis of porous polyaromatic column packings for GC analysis of extraterrestrial atmospheres

The preparation of a polymer for the Pioneer-Venus Large Probe Gas Chromatograph and another polymer for gas-chromatographic analysis of the Jovian atmosphere is described. Technical-grade divinylbenzene is used as a reliable and economical source of monomer for the preparation of polymer beads. The discussion covers monomeric preparation, polymerization apparatus, first-stage polymer beads, second-stage polymer beads, amino-polymer, columns and gas-chromatographic testing instrumentation used. The polymer for the Pioneer-Venus gas chromatograph is also suitable for ammonia but not for amine analysis. However, the polymer for the analysis of the Jovian atmosphere is a chemically derivatized aromatic polymer that is suitable for amine analysis. The two-stage polymerization produces a highly efficient polymer packing clearly superior to others prepared by adjusted dilution of the aqueous-organic suspension system.

Woeller, F. H.↗
DOE OSTI2022

Energy Transitions Initiative Partnership Project (ETIPP) [Slides]

These slides describe the U.S. Department of Energy's Energy Transitions Initiative Partnership Project (ETIPP). They include the ETIPP goals, partner network, technical assistance types, project timeline, and quotations by some communities selected for ETIPP in FY21.

24 POWER TRANSMISSION AND DISTRIBUTION↗
NASA NTRS2010

Systems Maintenance Automated Repair Tasks (SMART)

SMART is a uniform automated discrepancy analysis and repair-authoring platform that improves technical accuracy and timely delivery of repair procedures for a given discrepancy (see figure a). SMART will minimize data errors, create uniform repair processes, and enhance the existing knowledge base of engineering repair processes. This innovation is the first tool developed that links the hardware specification requirements with the actual repair methods, sequences, and required equipment. SMART is flexibly designed to be useable by multiple engineering groups requiring decision analysis, and by any work authorization and disposition platform (see figure b). The organizational logic creates the link between specification requirements of the hardware, and specific procedures required to repair discrepancies. The first segment in the SMART process uses a decision analysis tree to define all the permutations between component/ subcomponent/discrepancy/repair on the hardware. The second segment uses a repair matrix to define what the steps and sequences are for any repair defined in the decision tree. This segment also allows for the selection of specific steps from multivariable steps. SMART will also be able to interface with outside databases and to store information from them to be inserted into the repair-procedure document. Some of the steps will be identified as optional, and would only be used based on the location and the current configuration of the hardware. The output from this analysis would be sent to a work authoring system in the form of a predefined sequence of steps containing required actions, tools, parts, materials, certifications, and specific requirements controlling quality, functional requirements, and limitations.

Schuh, Joseph↗
NASA NTRS1992

Probabilistic Structural Analysis Methods for select space propulsion system components (PSAM). Volume 2: Literature surveys of critical Space Shuttle main engine components

The technical effort and computer code development is summarized. Several formulations for Probabilistic Finite Element Analysis (PFEA) are described with emphasis on the selected formulation. The strategies being implemented in the first-version computer code to perform linear, elastic PFEA is described. The results of a series of select Space Shuttle Main Engine (SSME) component surveys are presented. These results identify the critical components and provide the information necessary for probabilistic structural analysis. Volume 2 is a summary of critical SSME components.

Rajagopal, K. R.↗
NASA NTRS1991

Optical fiber sensors for materials and structures characterization

The final technical report on Optical Fiber Sensors for Materials and Structures Characterization, covering the period August 1990 through August 1991 is presented. Research programs in the following technical areas are described; sapphire optical fiber sensors; vibration analysis using two-mode elliptical core fibers and sensors; extrinsic Fabry-Perot interferometer development; and coatings for fluorescent-based sensor. Research progress in each of these areas was substantial, as evidenced by the technical publications which are included as appendices.

Lindner, D. K.↗
NASA NTRS2005

Genesis Reentry Observations and Data Analysis

The Genesis spacecraft reentry represented a unique opportunity to observe a "calibrated meteor" from northern Nevada. Knowing its speed, mass, composition, and precise trajectory made it a good subject to test some of the algorithms used to determine meteoroid mass from observed brightness. It was also a good test of an inexpensive set of cameras that could be deployed to observe future shuttle reentries. The utility of consumer-grade video cameras was evident during the STS-107 accident investigation, and the Genesis reentry gave us the opportunity to specify and test commercially available cameras that could be used during future reentries. This Technical Memorandum describes the video observations and their analysis, compares the results with a simple photometric model, describes the forward scatter radar experiment, and lists lessons learned from the expedition and implications for the Stardust reentry in January 2006 as well as future shuttle reentries.

Suggs, R. M.↗
DOE OSTI2022

A Methodological Overview of Seismic Analysis for Nuclear Event Detection

Underground explosions generate potentially detectable signatures, including energy waves that travel through the Earth’s subsurface (i.e., seismic waves), low-frequency sound waves (i.e., infrasound and hydroacoustic waves), and radioactive gases and/or particles that might leak from the test cavity (if the event was nuclear). There can also be intelligence indicators of a test, such as observations of modified patterns of life and activity at a suspected test site. If all of these detectable signatures and intelligence indicators are present and self-consistent, then analysts have high confidence in classifying a signature generating event as an explosion. However, because only partial information about an event is likely to be available, determining whether an event was natural (e.g., an earthquake or landslide) or manmade (e.g., a chemical or nuclear explosion) is much more challenging. This primer describes how one category of event signatures—seismic signatures—can augment event analyses. While universities and government organizations have generated detailed technical descriptions of seismic analytic techniques, we seek to translate seismic event analysis for a broad, non-technical audience. When the geologic conditions near an event are well-characterized, seismic data can be used to calculate critical information, such as event location and depth, with relatively high accuracy. Moreover, specific features within seismic datasets can help determine whether an event was an explosion. However, a key challenge in seismic analysis is that geologic site conditions are often poorly characterized, complicating the ability to discern the true nature of the event. To overcome this challenge, geologists answer a series of questions (discussed in section 1) to guide seismic event analysis and determine the most probable nature of an event. As more information is gathered during each analytic step, confidence grows regarding the nature of the event. Section 2 addresses uncertainties in seismic analysis and the vital nature of high-fidelity geologic data for accurate seismic event analysis.

58 GEOSCIENCES↗