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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 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Space and Defense Power Systems Maintenance Plan

Los Alamos National Laboratory (LANL) has more than forty years of experience in developing, characterizing, testing, and manufacturing plutonium-238 ( 238 Pu) heat sources. The LANL heat source program has made significant contributions to the United States space, defense, and national security missions, as well as the nuclear-powered artificial heart program. Currently, the Office of Space and Defense Power Systems (SDPS), located in the Nuclear Energy Group (NE-75), funds LANL for the infrastructure and processes used to store, recover, manufacture, and test 238 PuO 2 heat sources. LANL is an approved supplier of the General Purpose Heat Source (GPHS), which is a 238 PuO 2 Fueled Clad designed to provide 62.5 thermal watts. The Light Weight Radioisotope Heater Unit (LWRHU) is another 238 PuO 2 fueled heat source manufactured at LANL. The LWRHU is designed to provide one thermal watt in various locations on a spacecraft. LANL also supports the manufacture of other heat sources for various customers.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2018

Instrumentation for Hanford Direct-Feed Low-Activity Waste Real-Time, In-Line Process Monitoring - 18339

The direct-feed low-activity waste (DFLAW) process will utilize facilities in the Hanford tank farms to stage tank waste feed, a new facility to pretreat the tank waste feed, and facilities in the Hanford Waste Treatment and Immobilization Plant (WTP) to immobilize the low-activity waste (LAW) and disposition effluents from the vitrification process. Process sampling is used extensively throughout the DFLAW process to qualify waste feeds, control the process, and demonstrate compliance with regulatory and contractual commitments. The U.S. Department of Energy's Office of River Protection (ORP) has started a program to evaluate the potential benefits of replacing some sample collection requirements with realtime, in-line monitoring (RTIM). The program will identify, develop, and evaluate technologies that can reduce the number of samples required for WTP operation. Potential benefits of RTIM include elimination of process holds for sample analysis, a reduction in worker exposure to radiation and chemical hazards, decreased secondary waste volume, reducing the cost for sample collection and analysis, an improvement in product quality, and timely indication of process anomalies. In order to incorporate RTIM, the process control strategy for the overall process, as well as each unit operation, was reviewed and revisions to the strategies proposed. The following items were identified for incorporation of RTIM: - Real-time material balance calculations linked to the process control system; - Use of RTIM instruments to validate the material balance for selected analytes; - Anion analysis for determination of selected semi-volatile species (e.g., chlorine, sulfur, and fluorine) in the recycle stream. Based on the proposed process control strategy, a preliminary list of potential analytical equipment was developed. This was followed by a preliminary survey of instrument technologies currently on the market building on surveys performed for ORP, literature reviews, vendor web sites, and subject matter experts from the Savannah River National Laboratory and other U.S. Department of Energy national laboratories. Each technology was evaluated for measurement capability, operations and maintenance requirements, space requirements, and potential for application as process control instrumentation. The instrument technologies were chosen based on the following criteria: - Ability to perform analyses needed; - Potential to be used or adapted for use as process control instruments; - Potential to be adapted to size and operational constraints of standard WTP sample cabinets; - Operational and maintenance requirements. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

The Development and Implementation of Instruction and Remote Access Components of Additive Manufacturing

Additive manufacturing (AM), also known as 3D printing, is one of the latest emerging widespread production technologies. Almost any complex-part geometry is easily made using this technology and is usually used reliably. Many implementations of AM exist from areas as diverse as food industry to biomedical engineering; such a broad-spectrum usage of this technology makes it extremely attractive when combined with its low cost, reliability, color range, and complexity abilities.Though the cost of buying new AM machines varies greatly depending on the size of the machines (AM equipment ranges from desktop printers to very large production machines), AM equipment is still not affordable for many educational institutions due to limited or low equipment, consumable supplies, physical space, and maintenance budgets. Such issues become even more important for educational organizations in underserved and underdeveloped districts, which typically have inadequate support from their constituents.To address this issue, AM laboratories and their functionalities can easily be made available through the internet. Educational institutions which do not have the capability of AM technologies can easily access and utilize other laboratories’ capabilities. In the past, various remotely accessible AM laboratories such as these have been introduced, and their advantages and limitations in various P16 STEM (science, technology, engineering, and mathematics) practices have been reported. In this chapter, the authors introduce a novel concept of accessing external AM laboratories via smartphones and advanced computer technologies.

Fidan, Ismail↗
DOE OSTI2024

Adaptive Framework for Maintenance Scheduling Based on Dynamic Preventive Intervals and Remaining Useful Life Estimation

Data-based prognostic methods exploit sensor data to forecast the remaining useful life (RUL) of industrial settings to optimize the scheduling of maintenance actions. However, implementing sensors may not be cost-effective or practical for all components. Traditional preventive approaches are not based on sensor data; however, they schedule maintenance at equally spaced intervals, which is not a cost-effective approach since the distribution of the time between failures changes with the degradation state of other parts or changes in working conditions. This study introduces a novel framework comprising two maintenance scheduling strategies. In the absence of sensor data, we propose a novel dynamic preventive policy that adjusts intervention intervals based on the most recent failure data. When sensor data are available, a method for RUL prediction, designated k-LSTM-GFT, is enhanced to dynamically account for RUL prediction uncertainty. The results demonstrate that dynamic preventive maintenance can yield cost reductions of up to 51.8% compared to conventional approaches. The predictive approach optimizes the exploitation of RUL, achieving costs that are only 3–5% higher than the minimum cost achievable while ensuring the safety of critical systems since all of the failures are avoided.

Nunes, Pedro (ORCID:0000000180012172)↗
DOE OSTI2021

Performance Evaluation of Comparative Vacuum Monitoring and Piezoelectric Sensors for Structural Health Monitoring of Rotorcraft Components

The costs associated with the increasing maintenance and surveillance needs of aging structures are rising at an unexpected rate. Multi-site fatigue damage, hidden cracks in hard-to-reach locations, disbonded joints, erosion, impact, and corrosion are among the major flaws encountered in today’s extensive fleet of aging aircraft and space vehicles. Aircraft maintenance and repairs represent about a quarter of a commercial fleet’s operating costs. The application of Structural Health Monitoring (SHM) systems using distributed sensor networks can reduce these costs by facilitating rapid and global assessments of structural integrity. The use of in-situ sensors for real-time health monitoring can overcome inspection impediments stemming from accessibility limitations, complex geometries, and the location and depth of hidden damage. Reliable, structural health monitoring systems can automatically process data, assess structural condition, and signal the need for human intervention. The ease of monitoring an entire on-board network of distributed sensors means that structural health assessments can occur more often, allowing operators to be even more vigilant with respect to flaw onset. SHM systems also allow for condition-based maintenance practices to be substituted for the current time-based or cycle-based maintenance approach thus optimizing maintenance labor. The Federal Aviation Administration has conducted a series of SHM validation and certification programs intended to comprehensively support the evolution and adoption of SHM practices into routine aircraft maintenance practices. This report presents one of those programs involving a Sandia Labs-aviation industry effort to move SHM into routine use for aircraft maintenance. The Airworthiness Assurance NDI Validation Center (AANC) at Sandia Labs, in conjunction with Sikorsky, Structural Monitoring Systems Ltd., Anodyne Electronics Manufacturing Corp., Acellent Technologies Inc., and the Federal Aviation Administration (FAA) carried out a trial validation and certification program to evaluate Comparative Vacuum Monitoring (CVM) and Piezoelectric Transducers (PZT) as a structural health monitoring solution to specific rotorcraft applications. Validation tasks were designed to address the SHM equipment, the health monitoring task, the resolution required, the sensor interrogation procedures, the conditions under which the monitoring will occur, the potential inspector population, adoption of CVM and PZT systems into rotorcraft maintenance programs and the document revisions necessary to allow for their routine use as an alternate means of performing periodic structural inspections. This program addressed formal SHM technology validation and certification issues so that the full spectrum of concerns, including design, deployment, performance and certification were appropriately considered. Sandia Labs designed, implemented, and analyzed the results from a focused and statistically relevant experimental effort to quantify the reliability of a CVM system applied to Sikorsky S-92 fuselage frame application and a PZT system applied to an S-92 main gearbox mount beam application. The applications included both local and global damage detection assessments. All factors that affect SHM sensitivity were included in this program: flaw size, shape, orientation and location relative to the sensors, as well as operational and environmental variables. Statistical methods were applied to performance data to derive Probability of Detection (POD) values for SHM sensors in a manner that agrees with current nondestructive inspection (NDI) validation requirements and is acceptable to both the aviation industry and regulatory bodies. The validation work completed in this program demonstrated the ability of both CVM and PZT SHM systems to detect cracks in rotorcraft components. It proved the ability to use final system response parameters to provide a Green Light/Red Light (“GO” – “NO GO”) decision on the presence of damage. In additional to quantifying the performance of each SHM system for the trial applications on the S-92 platform, this study also identified specific methods that can be used to optimize damage detection, guidance on deployment scenarios that can affect performance and considerations that must be made to properly apply CVM and PZT sensors. These results support the main goal of safely integrating SHM sensors into rotorcraft maintenance programs. Additional benefits from deploying rotorcraft Health and Usage Monitoring Systems (HUMS) may be realized when structural assessment data, collected by an SHM system, is also used to detect structural damage to compliment the operational environment monitoring. The use of in-situ sensors for health monitoring of rotorcraft structures can be a viable option for both flaw detection and maintenance planning activities. This formal SHM validation will allow aircraft manufacturers and airlines to confidently make informed decisions about the proper utilization of CVM and PZT technology. It will also streamline future regulatory actions and formal certification measures needed to assure the safe application of SHM solutions.

42 ENGINEERING↗
DOE OSTI2011

AN INITIAL ASSESSMENT OF POTENTIAL PRODUCTION TECHNOLOGIES FOR EPSILON-METAL WASTE FORMS

This report examines and ranks a total of seven materials processing techniques that may be potentially utilized to consolidate the undissolved solids from nuclear fuel reprocessing into a low-surface area form. Commercial vendors of processing equipment were contacted and literature researched to gather information for this report. Typical equipment and their operation, corresponding to each of the seven techniques, are described in the report based upon the discussions and information provided by the vendors. Although the report does not purport to describe all the capabilities and issues of various consolidation techniques, it is anticipated that this report will serve as a guide by highlighting the key advantages and disadvantages of these techniques. The processing techniques described in this report were broadly classified into those that employed melting and solidification, and those in which the consolidation takes place in the solid-state. Four additional techniques were examined that were deemed impractical, but were included for completeness. The techniques were ranked based on criteria such as flexibility in accepting wide-variety of feed-stock (chemistry, form, and quantity), ease of long-term maintenance, hot cell space requirements, generation of additional waste streams, cost, and any special considerations. Based on the assumption of ~2.5 L of waste to be consolidated per day, sintering based techniques, namely, microwave sintering, spark plasma sintering and hot isostatic pressing, were ranked as the top-3 choices, respectively. Melting and solidification based techniques were ranked lower on account of generation of volatile phases and difficulties associated with reactivity and containment of the molten metal.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2013

Evaluation of the Total Cost of Ownership of Fuel Cell-Powered Material Handling Equipment

This report discusses an analysis of the total cost of ownership of fuel cell-powered and traditional battery-powered material handling equipment (MHE, or more typically 'forklifts'). A number of fuel cell MHE deployments have received funding support from the federal government. Using data from these government co-funded deployments, DOE's National Renewable Energy Laboratory (NREL) has been evaluating the performance of fuel cells in material handling applications. NREL has assessed the total cost of ownership of fuel cell MHE and compared it to the cost of ownership of traditional battery-powered MHE. As part of its cost of ownership assessment, NREL looked at a range of costs associated with MHE operation, including the capital costs of battery and fuel cell systems, the cost of supporting infrastructure, maintenance costs, warehouse space costs, and labor costs. Considering all these costs, NREL found that fuel cell MHE can have a lower overall cost of ownership than comparable battery-powered MHE.

25 ENERGY STORAGE↗
DOE OSTI2012

Manufacturing Process Modeling of 100-400 kW e Combined Heat and Power Stationary Fuel Cell Systems

A one year project to examine the processes employed in the manufacture of combined heat and power stationary fuel cells operating in the 100-400kWe range was commissioned in June 2010. The results of this project would be used to inform decision makers in charge of allocating R&D resources by highlighting the most expensive steps in the manufacturing process where processing alternatives might have the greatest potential for high impact cost reduction. Three fuel cell technologies were examined: phosphoric acid (PAFC), molten carbonate (MCFC), and solid oxide (SOFC) fuel cells. Two fuel cell technologies, PAFC and MCFC, are represented by commercially available products within the study boundaries. United Technologies Corporation (UTC) offers the PureCell 400 ® , a 400 kWe combined heat and power PAFC system. FuelCell Energy (FCE) offers the DFC-300 ® , a 375 kWe combined heat and power MCFC. A combined heat and power SOFC within the study boundaries is not available in the marketplace at the time of this study. Process based cost models using 2010 dollars were developed for each fuel cell technology. For all three technologies, model boundaries encompassed all direct and indirect materials; direct and indirect labor; capital, maintenance, tooling, floor space, and energy costs associated with the manufacturing process. Cost estimates were developed with academic and patent literature, industry partners, supplier quotations, Monte Carlo simulation software, and DFMA software. Life cycle and non-manufacturing costs such as sales, administration, R&D, office floor space, and profit were not quantified. Results presented are for assumed annual production volumes of 5, 20, 50, and 500 MWe/yr, and expressed in terms of dollars per kilowatt of electrical energy. A model baseline production volume of 20 MWe/yr (similar to recent production volumes experienced by UTC and FCE) was assumed for all three technologies.

Warren, Joshua A.↗
DOE OSTI2015

University of Maryland Wall Washer Retrofit - LED Modules Replace Halogen Lamps in a Performing Arts Center

The University of Maryland (UMD) began retrofitting halogen wall washers in the Clarice Smith Performing Arts Center (CSPAC) in April 2014. The U.S. Department of Energy (DOE) Solid-State Lighting (SSL) GATEWAY program documented this process through the final installation in March 2015, summarized in this report. The wall washers illuminate hallways lining the atrium, providing task illuminance for transitioning between spaces and visual interest to the atrium boundaries. The main goals of the retrofit were to maintain the visual appearance of the space while reducing maintenance costs – energy savings was considered an additional benefit by UMD Facilities Management. UMD Facilities Management is pleased with the results of this retrofit, and continues to initiate LED retrofit projects across the UMD campus.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2020

Raising the Bar in High Performance Laboratory Design

Laboratory facilities are expensive to build and operate, they consume energy at high rates compared to other types of buildings, and modifications are frequently required to accommodate ever-changing research activities. PNNL sought ways to address these issues in the design and construction of a 14,700 sq. ft. new laboratory building. To improve adaptability to change a high roof structure was used that allows raising the ceiling when needed with minimal disruption to installed HVAC and electrical utilities. Also, HVAC equipment was located on a mezzanine above the central corridor rather than above ceilings. This eliminates the need for maintenance personnel to routinely access lab spaces, reducing disruption to research staff and improving maintenance access. To improve the reliability of operations while reducing energy consumption, heat pipe heat recovery with evaporative cooling, zoned heating/cooling coils, high-efficiency condensing boilers, district cooling, VAV fume hoods, DDC controls, energy use monitoring, and implementation of the US Department of Energy’s Guiding Principles for Federal Leadership in Sustainable Buildings were all used. The energy model developed during design projected energy use at 2,840 MBtu/yr, a 13.5% savings over ASHRAE Standard 90.1-2010. The first full year of operation resulted in actual energy use of 2,661 MBtu, a savings of 19% over Standard 90.1. As a result of the project design’s demonstrated success, these strategies will be incorporated into a significantly larger (125,000 sq ft), $65 million lab facility to be constructed on the PNNL campus in 2020.

Scott, Jeffery M.↗
DOE OSTI2011

Design and Fabrication of the Lithium Beam Ion Injector for NDCX-II

A 130 keV injector is developed for the NDCX-II facility. It consists of a 10.9 cm diameter lithium doped alumina-silicate ion source heated to {approx}1300 C and 3 electrodes. Other components include a segmented Rogowski coil for current and beam position monitoring, a gate valve, pumping ports, a focusing solenoid, a steering coil and space for inspection and maintenance access. Significant design challenges including managing the 3-4 kW of power dissipation from the source heater, temperature uniformity across the emitter surface, quick access for frequent ion source replacement, mechanical alignment with tight tolerance, and structural stabilization of the cantilevered 27-inch OD graded HV ceramic column. The injector fabrication is scheduled to complete by May 2011, and assembly and installation is scheduled to complete by the beginning of July. The Neutralized Drift Compression eXperiment (NDCX-II) is for the study of high energy density physics and inertial fusion energy research utilizing a lithium ion (Li+) beam with a current of 93 mA and a pulse length of 500 ns (compressed to 1 ns at the target). The injector is one of the most complicated sections of the NDCX-II accelerator demanding significant design and fabrication resources. It needs to accommodate a relatively large ion source (10.9 cm), a high heat load (3-4 kW) and specific beam optics developed from the physics model. Some specific design challenges are noted in this paper.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2017

Space vehicle chassis

A modular space vehicle chassis may facilitate convenient access to internal components of the space vehicle. Each module may be removable from the others such that each module may be worked on individually. Multiple panels of at least one of the modules may swing open or otherwise be removable, exposing large portions of the internal components of the space vehicle. Such chassis architectures may reduce the time required for and difficulty of performing maintenance or modifications, may allow multiple space vehicles to take advantage of a common chassis design, and may further allow for highly customizable space vehicles.

42 ENGINEERING↗
DOE OSTI2018

Space vehicle chassis

A modular space vehicle chassis may facilitate convenient access to internal components of the space vehicle. Each module may be removable from the others such that each module may be worked on individually. Multiple panels of at least one of the modules may swing open or otherwise be removable, exposing large portions of the internal components of the space vehicle. Such chassis architectures may reduce the time required for and difficulty of performing maintenance or modifications, may allow multiple space vehicles to take advantage of a common chassis design, and may further allow for highly customizable space vehicles.

42 ENGINEERING↗
DOE OSTI2016

KTF Sub-Area Plan: Overview & Summary

The KTF Sub-Area Plan is currently under development. Finalization awaits decisions regarding the long-term future of the site. The sub-area plan will build upon previous master plans, facilities and infrastructure (F&I) revitalization plans, and building studies. Planning concepts under consideration are: (1) Replace facilities with a combination of new permanent and non-permanent space; and (2) Complete deferred maintenance at remaining facilities.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2018

Extremely Low Resource Optical Identifier: A License Plate for Your Satellite

Space object identification is vital for operating spacecraft, space traffic control, and space situational awareness, but initial determination, maintenance, and recovery of identity are all difficult, expensive, and error prone, especially for small objects like CubeSats. Attaching a beacon or license plate with a unique identification number to a space object before launch would greatly simplify the task, but radio beacons are power hungry and can cause interference. This work describes a new concept for a satellite license plate: the extremely low resource optical identifier. The extremely low resource optical identifier is a milliwatt-scale self-powered autonomous optical beacon that can be attached to any space object to transmit a persistent identification signal to ground stations. A system appropriate for a low-Earth-orbit CubeSat or other small space object can fit in a package with the area of a postage stamp and a few millimeters thick; and it requires no power, data, or control from the host object. The concept has been validated with ground tests, and the first flight-test unit is scheduled for launch in 2018. The unique identification number of a low-Earth-orbit satellite can be determined unambiguously in a single orbital pass over a low-cost ground station.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2015

Quo vadis? Microbial profiling revealed strong effects of cleanroom maintenance and routes of contamination in indoor environments

Space agencies maintain highly controlled cleanrooms to ensure the demands of planetary protection. To study potential effects of microbiome control, we analyzed microbial communities in two particulate-controlled cleanrooms (ISO 5 and ISO 8) and two vicinal uncontrolled areas (office, changing room) by cultivation and 16S rRNA gene amplicon analysis (cloning, pyrotagsequencing, and PhyloChip G3 analysis). Maintenance procedures affected the microbiome on total abundance and microbial community structure concerning richness, diversity and relative abundance of certain taxa. Cleanroom areas were found to be mainly predominated by potentially human-associated bacteria; archaeal signatures were detected in every area. Results indicate that microorganisms were mainly spread from the changing room (68%) into the cleanrooms, potentially carried along with human activity. The numbers of colony forming units were reduced by up to ~400 fold from the uncontrolled areas towards the ISO 5 cleanroom, accompanied with a reduction of the living portion of microorganisms from 45% (changing area) to 1% of total 16S rRNA gene signatures as revealed via propidium monoazide treatment of the samples. Our results demonstrate the strong effects of cleanroom maintenance on microbial communities in indoor environments and can be used to improve the design and operation of biologically controlled cleanrooms.

42 ENGINEERING↗
DOE OSTI2012

Measure Guideline: Evaporative Condensers

The purpose of this measure guideline on evaporative condensers is to provide information on a cost-effective solution for energy and demand savings in homes with cooling loads. This is a prescriptive approach that outlines selection criteria, design and installation procedures, and operation and maintenance best practices. This document has been prepared to provide a process for properlydesigning, installing, and maintaining evaporative condenser systems as well as understanding the benefits, costs, and tradeoffs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2012

Advanced light ion source extraction system for a new electron cyclotron resonance ion source geometry at Saclay

One of the main goal of intense light ion injector projects such as IPHI, IFMIF, or SPIRAL2, is to produce high current beams while keeping transverse emittance as low as possible. To prevent emittance growth induced in a dual solenoid low energy transfer line, its length has to be minimized. This can be performed with the advanced light ion source extraction system concept that we are developing: a new ECR 2.45 GHz type ion source based on the use of an additional low energy beam transport (LEBT) short length solenoid close to the extraction aperture to create the resonance in the plasma chamber. The geometry of the source has been considerably modified to allow easy maintenance of each component and to save space in front of the extraction. The source aims to be very flexible and to be able to extract high current ion beams at energy up to 100 kV. A specific experimental setup for this source is under installation on the BETSI test bench, to compare its performances with sources developed up to now in the laboratory, such as SILHI, IFMIF, or SPIRAL2 ECR sources. This original extraction source concept is presented, as well as electromagnetic simulations with OPERA-2D code. Ion beam extraction in space charge compensation regime with AXCEL, and beam dynamics simulation with SOLMAXP codes show the beam quality improvement at the end of the LEBT.

43 PARTICLE ACCELERATORS↗