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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 433 records · Page 24
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Embedded sensors integrated into critical components for in situ health monitoring of steam turbines

Operational flexibility is desired in today’s coal-fired power plants to balance power grids by compensating for the variable electricity supply from renewable energy sources and distributed gensets. This demanding requirement accelerates materials degradation and makes in-situ health monitoring essential. Life monitoring of components and subsystems is thus seen as essential in assessing material and mechanical behavior to estimate system reliability, move to a conditionbased maintenance strategy and determine time to failure of the units in their actual operating conditions. Vibration monitoring can be exploited for blade tip timing to measure blade vibration amplitude and tip clearance to detect any deterioration taking place in the condition of steam turbine blades. A failure of a rotating blade can lead to severe turbine damage followed by extensive repairs and loss of power production. A blade vibration monitoring system can help early detection of abnormal blade vibration behavior. In conjunction with a health monitoring system, the vibration characteristics can be analyzed to support a pro-active maintenance and inspection schedule. While the feasibility of this inspection technique has been amply demonstrated, there is a need to install induction probes to magnetize the blade for signal output. Siemens, in partnership with Raytheon Technologies Research Corporation (RTRC), proposes a holistic approach to develop embedded sensors to utilize radio frequency for not only coupling to sensors, but as the sensing modality. The goal of this project is to “embed” the novel sensing approach by using either additively manufactured or extruded waveguides on rotating blades for recording, evaluation and monitoring of blade vibrations in Low Pressure turbines, with applications extending to aero engines

01 COAL, LIGNITE, AND PEAT↗
NASA NTRS1988

Noncontacting Inspection Heads For Robots

Compact assembly for hand of robot includes group of sensors to monitor internal conditions of such complex equipment as turbines, pumps, motors, and generators. Inspection head includes sensors; for example, pyrometers, isotope wear analyzers, spectrometers, and interferometers. Conditions as overheating of turbines, wear of ball bearings and seals, erosion of blades and impellers, leakage of joints, and deformations of housings, monitored without disassembly or shutdown. Used in typical robot applications.

Barkhoudarian, Sarkis↗
NASA NTRS1973

Safety monitoring system for radioisotope thermoelectric generators

System alerts personnel of hazards which may develop while they are performing tests on radioisotope thermoelectric generator (RTG). Remedial action is initiated to minimize damage. Five operating conditions are monitored: hot junction temperature, cold junction temperature, thermal shroud coolant flow, vacuum in test chamber, and alpha radiation.

Zoltan, A.↗
DOE OSTI2016

Evaluation of Neutron Absorber Panels from Zion Spent Fuel Pool

In spent fuel pools (SFPs), fixed neutron absorber materials are used to increase storage capacity while maintaining criticality safety margins. BORAL{sup R} is a commonly used neutron absorber material for both wet (SFPs) and dry storage (casks). The specific questions surrounding fixed neutron absorber materials include the following: 1. What are the conditions of the neutron absorber panels in SFPs? Is there any gross degradation that could cause potential concern for criticality safety of the pools? 2. Is the coupon monitoring approach adequate for monitoring the conditions of the panels as part of an aging management program? 3. For plants that do not have coupons, do current in situ measurement approaches provide accurate results? Could such in situ approaches be used as an alternative monitoring approach? In order to shed light on these technical questions using actual plant data, EPRI initiated the Zion comparative analysis project at the decommissioning Zion Nuclear Power Plant in late 2014. An overview of the Zion plant, SFP, and project was described in a previous publication. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2023

Evaluation of Digital Twin Modeling and Simulation

A digital twin has intelligent modules that continuously monitor the condition of the individual components and the whole of a system. Digital twins can provide nuclear power plants (NPP) operators an unprecedented level of monitoring, control, supervision, and security by contributing a greater volume of data for more comprehensive data analysis and increased accuracy of insights and predictions for decision making throughout the entire NPP lifecycle. NPP operators and managers have historically relied on limited, second hand or incomplete data. With proper implementation, digital twins can provide a central hub of all intel that allows for a multidisciplinary view of an NPP. This equips operators and managers with the ability to have more information, context, and intel that can be used for greater granularity during planning and decision making. Digital twins can be used in many activities as the technology has many different concepts surrounding it. From the various definitions of a digital twin within the industry, digital twins can be differentiated by levels of integration/automation. The three main models include digital model, digital shadow, and digital twin. Digital twins offer many potential advancements to the nuclear industry that could reduce costs, improve designs, provide safer operation, and improve their overall security.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
NASA NTRS1990

Remote sensing of tropical forests - An overview of research and applications using non-photographic sensors

A comprehensive overview is presented on how remote sensing technology has been applied to tropical forest monitoring over the past 20 years. Research needs for monitoring the condition and extent of tropical forests are suggested. The discussion focuses on nonphotographic sensors, especially those on orbiting satellites. Several remote sensing approaches to tropical forest monitoring are outlined, including NOAA AVHRR, Landsat MSS, the Landsat Thematic Mapper, SPOT-1, and Synthetic Aperture Radar. Suggested research needs are addressed, along with discussions on the use of Geographic Information Systems, and multistage and multisensor approaches in data analysis and acquisition. It is concluded that additional research and technique development is urgently needed to advance the utility of remotely sensed data for tropical forest monitoring. However, there is sufficient information available now to prototype a global tropical forest monitoring system that would utilize current satellite sensors complemented with airborne sensors for detailed measurements on sample locations.

Sader, Steven A.↗
NASA NTRSDate not supplied

In-situ Inspection of Reflowable-Interface Composite Joints During Cure in an Autoclave

In structural bonds, the interface between adherend and adhesive is nearly two-dimensional making it susceptible to minute quantities of contamination, which can cause weak bonds. Regulatory organizations such as the Federal Aviation Administration (FAA) often require redundant load paths in secondary-bonded, primary-structures to alleviate concerns with bonded performance. Under NASA’s Convergent Aeronautics Solutions (CAS) project, the Adhesive Free Bonding of Composites (AERoBOND) project is investigating reformulated aerospace epoxy-matrix resins to enable reflow and diffusion of the resin at the joint interface during a secondary bonding and cure process. The reflow and intermixing of the matrix resin during assembly can eliminate the material discontinuity at the interface, thereby removing the dependence of bond performance on adhesion at a nearly two-dimensional boundary. AERoBOND process development has evaluated a multitude of parameters including the materials used, the stoichiometric offset of the epoxy resins, time and temperature of cure, and thickness of each ply. Without in-situ process monitoring, the condition of a test article is unknown until mechanical testing is completed. This presentation describes the use of an in-situ ultrasonic inspection system to monitor the joining of two composite parts assembled using the AERoBOND technique. This work quantifies the elimination of the interface by measuring the wave reflection, or lack thereof, at the joint throughout the cure cycle. In addition, the results indicate when reflow and cure of the epoxy resin at the joint occurred. By using the recently developed in-situ inspection with a mobile ultrasonic transducer, localized results can be obtained across a large portion of the joint with high resolution.

Tyler B Hudson↗
NASA NTRSDate not supplied

In-situ Inspection of Reflowable-Interface Composite Joints During Cure in an Autoclave

In structural bonds, the interface between adherend and adhesive is nearly two-dimensional making it susceptible to minute quantities of contamination, which can cause weak bonds. Regulatory organizations such as the Federal Aviation Administration (FAA) often require redundant load paths in secondary-bonded, primary-structures to alleviate concerns with bonded performance. Under NASA’s Convergent Aeronautics Solutions (CAS) project, the Adhesive Free Bonding of Composites (AERoBOND) project is investigating reformulated aerospace epoxy-matrix resins to enable reflow and diffusion of the resin at the joint interface during a secondary bonding and cure process. The reflow and intermixing of the matrix resin during assembly can eliminate the material discontinuity at the interface, thereby removing the dependence of bond performance on adhesion at a nearly two-dimensional boundary. AERoBOND process development has evaluated a multitude of parameters including the materials used, the stoichiometric offset of the epoxy resins, time and temperature of cure, and thickness of each ply. Without in-situ process monitoring, the condition of a test article is unknown until mechanical testing is completed. This presentation describes the use of an in-situ ultrasonic inspection system to monitor the joining of two composite parts assembled using the AERoBOND technique. This work quantifies the elimination of the interface by measuring the wave reflection, or lack thereof, at the joint throughout the cure cycle. In addition, the results indicate when reflow and cure of the epoxy resin at the joint occurred. By using the recently developed in-situ inspection with a mobile ultrasonic transducer, localized results can be obtained across a large portion of the joint with high resolution.

Tyler B Hudson↗
NASA NTRSDate not supplied

In-situ Inspection of Reflowable-Interface Composite Joints During Cure in an Autoclave

In structural bonds, the interface between adherend and adhesive is nearly two-dimensional making it susceptible to minute quantities of contamination, which can cause weak bonds. Regulatory organizations such as the Federal Aviation Administration (FAA) often require redundant load paths in secondary-bonded primary-structures to alleviate the inability to certify bonded performance. To address this issue, the NASA Convergent Aeronautics Solutions (CAS): Adhesive Free Bonding of Composites (AERoBOND) project is investigating reformulated aerospace epoxy-matrix resins to enable reflow and diffusion of the resin at the joint interface during a secondary bonding and cure process. The reflow and intermixing of the matrix resin during assembly can eliminate the material discontinuity at the interface, thereby removing the dependence of bond performance on adhesion at a nearly two-dimensional boundary. AERoBOND process development has evaluated a multitude of parameters including the materials used, the stoichiometric offset of the epoxy resins, time and temperature of cure, and thickness of each ply. Without in-situ process monitoring, the condition of a test article is unknown until mechanical testing is completed. This paper describes the use of an in-situ ultrasonic inspection system to monitor the joining of two composite parts assembled using the AERoBOND technique. This work quantifies the interface by measuring the wave reflection, or lack thereof, at the joint throughout the cure cycle. In addition, the results indicate when reflow and cure of the epoxy resin at the joint occurred. By using the recently developed in-situ inspection method with a mobile ultrasonic transducer, localized results can be obtained across a large portion of the joint with high resolution.

Tyler B Hudson↗
DOE OSTI2014

Dry Cask Storage Inspection and Monitoring. Interim Report.

Recently, the U.S. Nuclear Regulatory Commission (NRC) issued the guidance on the aging management of dry storage facilities that indicates the necessity to monitor the conditions of dry cask storage systems (DCSSs) over extended periods of time.1 Part of the justification of the aging management plans is the requirement for inspection and monitoring to verify whether continued monitoring, inspection or mitigation are necessary. To meet this challenge Argonne National Laboratory (ANL) in collaboration with Idaho National Laboratory (INL) is conducting scoping studies on current and emerging nondestructive evaluation/examination (NDE) and online monitoring (OLM) technologies for DCSS integrity assessments. The scope of work plan includes identification and verification of technologies for long-term online monitoring of DCSSs’ crucial physical parameters such as temperature, pressure, leakage and structural integrity in general. Modifications have been made to the current technologies to accommodate field inspections and monitoring. A summary of the scoping studies and experimental efforts conducted to date as well as plans for future activities is provided below.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
NASA NTRS1975

Monitoring physical and chemical parameters of Delaware Bay waters with an ERTS-1 data collection platform

The author has identified the following significant results. Results of the analysis of data collected during the summer of 1974 demonstrate that the ERTS Data Collection Platform (DCP) is quite responsive to changing water parameters and that this information can be successfully transmitted under all weather conditions. The monitoring of on-site probe outputs reveals a rapid response to changing water temperature, salinity, and turbidity conditions on incoming tides as the tidal salt wedge passes the probe location. The changes in water properties were corroborated by simultaneously sampling the water for subsequent laboratory analysis. Fluctuations observed in the values of salinity, conductivity, temperature and water depth over short time intervals were extremely small. Due to the nature of the probe, 10% to 20% fluctuations were observed in the turbidity values. The use of the average of the values observed during an overpass provided acceptable results. Good quality data was obtained from the satellite on each overpass regardless of weather conditions. Continued use of the DCP will help provide an indication of the accuracy of the probes and transmission system during long term use.

Klemas, V.↗
DOE OSTI2019

Big Data Framework with Machine Learning for D and D Applications - 19108

The nuclear industry is experiencing a steady increase in maintenance costs even though plants are maintained under high levels of safety, capability and reliability. Nuclear power plants are expected to run every unit at maximum capacity at all times, efficiently utilizing assets with minimal downtime. Surveillance and maintenance of nuclear decommissioning infrastructure provides lot challenges with respect to maintenance or decommissioning of the buildings. There is a need for a framework to analyze the huge amount of data generated by the sensors on the nuclear reactor components as well as structures, to monitor the conditions of these building over a period of time. Emerging technologies such as big data analytics have become a requirement in the nuclear industry to improve structural health monitoring and diagnostics. FIU will make use of existing mature technologies in the areas of imaging, robotics, big data, and machine learning/deep learning to assess the structural integrity of aging facilities at DOE sites. As these facilities await decommissioning, there is a need to understand the structural health of these structures. Many of these facilities were built over 50 years ago and in some cases these facilities have gone beyond the operational life expectancy. In other cases, the facilities have been placed in a state of 'cold and dark' and they are sitting unused, awaiting decommissioning. Finally, some older facilities are one-of-a-kind operational/production facilities supporting critical DOE missions and cannot be shut down. In any of these scenarios, the structural integrity of these facilities may be compromised, so it is imperative that adequate inspections and data collection/analysis be performed on a continuous and ongoing basis. The primary goals of the research include collecting various formats of data such as structured, unstructured and streaming data from the various sensors deployed in buildings, collect videos/pictures from various imaging sources, ingest them using a Hadoop distributed file system and process the data using Spark to perform batch processing and real time analytics. Research and development on various machine learning/deep learning algorithms will also be performed to analyze the heterogeneous data collected from nuclear decommission infrastructure. FIU will design the big data framework to ingest, store and process huge amounts of heterogeneous data collected from many sources and optimize the algorithms to provide insights into the data and predict anomalies observed when compared against baseline conditions. Various modules of this framework will include heterogeneous data sources, message broker, Hadoop distributed file system, Spark for stream and batch processing, machine learning/ deep learning, Cassandra - persistent data store and visualization. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2014

Resilient Monitoring Systems: Architecture, Design, and Application to Boiler/Turbine Plant

Resilient monitoring systems, considered in this paper, are sensor networks that degrade gracefully under malicious attacks on their sensors, causing them to project misleading information. The goal of this work is to design, analyze, and evaluate the performance of a resilient monitoring system intended to monitor plant conditions (normal or anomalous). The architecture developed consists of four layers: data quality assessment, process variable assessment, plant condition assessment, and sensor network adaptation. Each of these layers is analyzed by either analytical or numerical tools. The performance of the overall system is evaluated using a simplified boiler/turbine plant. The measure of resiliency is quantified using Kullback-Leibler divergence, and is shown to be sufficiently high in all scenarios considered.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2013

Development of a novel ultrasonic temperature probe for long-term monitoring of dry cask storage systems

With the recent cancellation of the Yucca Mountain repository and the limited availability of wet storage utilities for spent nuclear fuel (SNF), more attention has been directed toward dry cask storage systems (DCSSs) for long-term storage of SNF. Consequently, more stringent guidelines have been issued for the aging management of dry storage facilities that necessitate monitoring of the conditions of DCSSs. Continuous health monitoring of DCSSs based on temperature variations is one viable method for assessing the integrity of the system. In the present work, a novel ultrasonic temperature probe (UTP) is being tested for long-term online temperature monitoring of DCSSs. Its performance was evaluated and compared with type N thermocouple (NTC) and resistance temperature detector (RTD) using a small-scale dry storage canister mockup. Our preliminary results demonstrate that the UTP system developed at Argonne is able to achieve better than 0.8 Degree-Sign C accuracy, tested at temperatures of up to 400 Degree-Sign C. The temperature resolution is limited only by the sampling rate of the current system. The flexibility of the probe allows conforming to complex geometries thus making the sensor particularly suited to measurement scenarios where access is limited.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Electrochemical Sensor Development for Fluoride Molten Salt Redox Control

Fluoride molten salts are proposed for many uses in the near future such as coolant for nuclear fission and fusion applications. This medium is advantageous due to superior heat transfer properties and chemical stability. These advantages result in better safety characteristics, increased output, and lower costs. These molten salts are sensitive to impurities, especially water and oxygen, however. These impurities can react with the fluorides to form hydrofluoric acid which will corrode the containing materials through the following mechanism: 2 HF + M → H{sub 2} + MF{sub 2}. Due to this sensitivity it is necessary to monitor the condition of the molten salt in order to prevent corrosion utilizing redox control. This study investigates the requirements and design of an electrochemical sensor which can perform this real time monitoring of the molten salt's redox potential.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2013

Y-12 Groundwater Protection Program Monitoring Well Inspection And Maintenance Plan

This document is the fourth revision of the Monitoring Well Inspection and Maintenance Plan for groundwater monitoring wells installed at the U.S. Department of Energy (DOE) Y-12 National Security Complex (Y-12) in Oak Ridge, Tennessee. This plan describes the systematic approach for:  inspecting the physical condition of monitoring wells at Y-12,  determining maintenance needs that extend the life of a well, and  identifying those wells that no longer meet acceptable monitoring well design or well construction standards and require plugging and abandonment.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2013

Y-12 Groundwater Protection Program Monitoring Well Inspection and Maintenance Plan

This document is the fourth revision of the Monitoring Well Inspection and Maintenance Plan for groundwater monitoring wells installed at the U.S. Department of Energy (DOE) Y-12 National Security Complex (Y-12) in Oak Ridge, Tennessee. This plan describes the systematic approach for: inspecting the physical condition of monitoring wells at Y-12, determining maintenance needs that extend the life of a well, and identifying those wells that no longer meet acceptable monitoring well design or well construction standards and require plugging and abandonment. This plan applies to groundwater monitoring wells installed at Y-12 and the related waste management facilities located within the three hydrogeologic regimes.

54 ENVIRONMENTAL SCIENCES↗