Characteristics of two large-scale jet-lift propulsion systems
Performance characteristics and hot exhaust gas ingestion problems for turbojet powered VTOL AIRCRAFT
HOT GAS↗
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Results for “INGESTION”
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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Experimental and theoretical study of the viscoseal.
Pressure patterns, gas ingestion and sealing capacity of viscoseals investigated using oil, water and liquid sodium as sealed fluids
INGESTION↗
The Effect of Incoming Boundary Layer Characteristics on the Performance of a Distributed Propulsion System
An experimental study is conducted in an effort to advance the understanding of flow physics associated with a boundary layer ingesting, distributed propulsion system. The influence of incoming boundary layer thickness and flow distortions are studied on the flow downstream and the overall performance of the system. The propulsion model, fabricated using additive manufacturing and integrated with electrical fans, is mounted on a flat plate and tested at subsonic speeds. Detailed characterization of the incoming boundary layer and subsequent assessment of the downstream flow field is performed using hotwire anemometry. Modification of the incoming boundary layer is achieved by placing tripping devices, such as rods and vortex generating ramps, near the leading edge of the flat plate. The overall performance of the system for different incoming flow conditions is analyzed by comparing magnitudes of exhaust velocities as well as estimated propulsive power to the corresponding baseline values. For a constant input power to the fans, smaller upstream flow distortions and moderately thickened boundary layers result in marginal changes in the flow field downstream. On the other hand, notable reductions in downstream flow velocities and propulsive power are observed in the case of a significantly thicker and/or distorted incoming boundary layer. It is hoped that this study will serve as a database for this technologically relevant flow field that has not been explored adequately before.
Propulsion↗
Electrical Propulsive Fuselage Concept for Transonic Transport Aircraft
NASA is broadly engaged in Electrified Aircraft Propulsion (EAP) efforts across air vehicle sizes and electric aircraft propulsion approaches. EAP enables a wide range of propulsion airframe integration options as well as the use of rechargeable energy storage in an aircraft. This paper is limited to a discussion of boundary layer ingestion (BLI) systems which are located on the fuselage of the aircraft and use electrical drive systems. We term that combination an "electrical propulsive fuselage". The benefits, challenges, and design parameters of an electrically driven fuselage BLI system are considered. Five existing types of fuselage BLI implementation approaches which can be implemented using either electrical or mechanical drive systems are reviewed. An overview of boundary layer types, fan response to boundary layer, and electrical system for aircraft propulsion is presented. An idea distributed electric propulsive fuselage is proposed.
Electrified Aircraft Propulsion↗
Update on ScreenVane Testing in W8
Summary of on-going work on the NASA AATT Boundary Layer Ingesting Tailcone System (BLITS) work. Includes a summary of the overall project as well as recent work on ScreenVane development and facility upgrades to test the BLI2DTF in the GRC W8 Facility
BLI↗
Blade Mistuning Analysis for Boundary Layer Inlet Flow Distortion-Tolerant Fan Blades
NASA Glenn Research Center has tested the BLI2DTF propulsor including the fan rotor. BLI2DTF stands for Boundary Layer Ingesting Inlet/Distortion-Tolerant Fan. A comparison of the vibratory response between analysis results and experimental wind tunnel test results yielded reasonable agreement, yet some differences were noted. Blade mistuning effects have been identified as a potential cause for these differences. A tuned forced response analysis in a turbomachinery engine rotor system assumes that all of the blades are identical, so that the natural frequencies of individual blades are the same. In contrast to this assumption, the wind tunnel tests of the BLI2DTF rotor system revealed that the individual blade response frequencies varied. These variations in individual blade frequencies may be attributed to blade mistuning due to potential differences in the structural and material properties of individual blades. For an understanding of these variations, it is necessary to analyze the influence of blade mistuning on the BLI2DTF rotor system, which will provide a more precise assessment of its vibratory stresses and high cycle fatigue life. The purpose of the study was to investigate the influence of blade mistuning on the dynamic characteristics of this rotor system. At the same fan operation condition, a comparative forced response analysis was performed for both tuned and mistuned BLI2DTF rotor systems. A comparison of the results from these analyses found that the mistuning effects on the present BLI2DTF rotor system are notable. As a result, fan blade mistuning is to be considered a contributor to the levels of vibratory dynamic stresses observed during the wind tunnel experiment.
Blade mistuning↗
The biokinetics of ruthenium in the human body
The biokinetics of ruthenium (Ru) in the human body is of interest due mainly to the potential for occupational or environmental exposure to 106Ru (T1/2 = 373.6 d) and 103Ru (T1/2 = 39.3 d), which typically represent a significant portion of the fission products in a reactor inventory. During reactor operations or nuclear fuel reprocessing these ruthenium isotopes may be present as ruthenium tetroxide (RuO4) vapor, a highly mobile form of ruthenium that has been involved in a number of cases of accidental exposure to 106Ru or 103Ru. This paper summarizes the biokinetic database for ruthenium and proposes a new respiratory model for inhaled RuO4 vapor, a new biokinetic for systemic (absorbed) ruthenium, and material-specific gastrointestinal absorption fractions for ruthenium. The proposed respiratory model for RuO4 differs from the current ICRP model mainly in that it depicts slower clearance of deposited activity from the respiratory tract and lower absorption to blood than depicted in the current ICRP model. The proposed systemic biokinetic model depicts more realistic paths of movement of absorbed ruthenium in the body than the current ICRP model and, in contrast to the present model, a less uniform distribution of systemic activity. Implications of the proposed models with regard to inhalation and ingestion dose coefficients for 106Ru are examined.
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
Radiological Modeling for Determination of Derived Concentration Levels of an Area with Uranium Residual Material - 13533
As a result of a pilot project developed at the old Spanish 'Junta de Energia Nuclear' to extract uranium from ores, tailings materials were generated. Most of these residual materials were sent back to different uranium mines, but a small amount of it was mixed with conventional building materials and deposited near the old plant until the surrounding ground was flattened. The affected land is included in an area under institutional control and used as recreational area. At the time of processing, uranium isotopes were separated but other radionuclides of the uranium decay series as Th-230, Ra-226 and daughters remain in the residue. Recently, the analyses of samples taken at different ground's depths confirmed their presence. This paper presents the methodology used to calculate the derived concentration level to ensure that the reference dose level of 0.1 mSv y-1 used as radiological criteria. In this study, a radiological impact assessment was performed modeling the area as recreational scenario. The modelization study was carried out with the code RESRAD considering as exposure pathways, external irradiation, inadvertent ingestion of soil, inhalation of resuspended particles, and inhalation of radon (Rn-222). As result was concluded that, if the concentration of Ra-226 in the first 15 cm of soil is lower than, 0.34 Bq g{sup -1}, the dose would not exceed the reference dose. Applying this value as a derived concentration level and comparing with the results of measurements on the ground, some areas with a concentration of activity slightly higher than latter were found. In these zones the remediation proposal has been to cover with a layer of 15 cm of clean material. This action represents a reduction of 85% of the dose and ensures compliance with the reference dose. (authors)
54 ENVIRONMENTAL SCIENCES↗
Giving Back: Collaborations with Others in Ecological Studies on the Nevada National Security Site - 13058
Formerly named the Nevada Test Site, the Nevada National Security Site (NNSS) was the historical site for nuclear weapons testing from the 1950's to the early 1990's. The site was renamed in 2010 to reflect the diversity of nuclear, energy, and homeland security activities now conducted at the site. Biological and ecological programs and research have been conducted on the site for decades to address the impacts of radiation and to take advantage of the relatively undisturbed and isolated lands for gathering basic information on the occurrence and distribution of native plants and animals. Currently, the Office of the Assistant Manager for Environmental Management of the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office (NNSA/NSO) oversees the radiological biota monitoring and ecological compliance programs on the NNSS. The top priority of these programs are compliance with federal and state regulations. They focus on performing radiological dose assessments for the public who reside near the NNSS and for populations of plants and animals on the NNSS and in protecting important species and habitat from direct impacts of mission activities. The NNSS serves as an invaluable outdoor laboratory. The geographic and ecological diversity of the site offers researchers many opportunities to study human influences on ecosystems. NNSA/NSO has pursued collaborations with outside agencies and organizations to be able to conduct programs and studies that enhance radiological biota monitoring and ecosystem preservation when budgets are restrictive, as well as to provide valuable scientific information to the human health and natural resource communities at large. NNSA/NSO is using one current collaborative study to better assess the potential dose to the off-site public from the ingestion of game animals, the most realistic pathway for off-site public exposure at this time from radionuclide contamination on the NNSS. A second collaborative study is furthering desert tortoise conservation measures onsite. It is the goal of NNSA/NSO to continue to develop such collaborations in the sharing of resources, such as personnel, equipment, expertise, and NNSS land access, with outside entities to meet mutually beneficial goals cost effectively. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
The Port Hope Areas Initiative's Port Granby Project: Radiation Protection Program - 17446
The Port Granby Project is large remediation project currently underway. A comprehensive and effective radiation protection program has been developed and implemented for the Port Granby Project. The potential radiation hazards associated with this project include: external (gamma) radiation, radon, inhalation, contamination and ingestion. Processes to address each of these potential hazards are identified. Measures of the effectiveness of the radiation protection program are also included. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Environmental sampling at Amchitka and Adak Islands, Alaska - 15317
Amchitka Island is near the western end of the Aleutian Islands, approximately 2157 km (1340 miles) west-southwest of Anchorage, Alaska. The US government conducted three underground nuclear tests on Amchitka between 1965 and 1971 and has conducted biological monitoring on the island since before 1965; the most recent monitoring occurred in the summer of 2011. A working group of stakeholders collected samples of marine biota, sediment, and sea water for analysis of test-related radionuclides to determine if subsistence- and commercial-catch seafood in the ocean near Amchitka and Adak Island (a reference area) is safe to eat. Dietary intake information for the risk estimates used a range of diets based on published surveys of four Aleut villages and a composite diet. The risk estimates indicated that seafood harvested at Amchitka and Adak is considered safe for consumption at the intake levels for each of five diets evaluated. Although increased cesium concentrations (Cs-134) possibly related to the Fukushima Dai-ichi event were detected in certain samples; the increased levels have not resulted in unacceptable risk from the ingestion of these seafoods. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Port Hope Area Initiative - Port Granby Project: Effectiveness of the Radiation Protection Program - 18595
The Port Granby Project is large remediation project currently underway. It is approximately 50% complete. A comprehensive and effective radiation protection program has been developed and implemented for the Port Granby Project. The potential radiation hazards associated with this project include: external (gamma) radiation, radon, inhalation, contamination and ingestion. The radiation protection program is highly effective and has succeeded in managing the significant radiation hazards associated with this remediation project. (authors)
61 RADIATION PROTECTION AND DOSIMETRY↗
Suite of Comprehensive Rapid Analysis Tools for Estimation (SOCRATES) - 19076
Long-term monitoring and remedy implementation require ongoing assessment and analytics, much of which relies on intensive and time-consuming data integration and engineering, data manipulation, and 'big-data' analytics. Many of these analyses, such as groundwater flow direction, contaminant rate attenuation, and non-parametric statistics, are spatial-temporal in nature and involve coalescing disparate data sets from a variety of sources with measurement frequencies from milliseconds to years, as well as total data volumes often exceeding the petabyte scale. Web-based analytical tools are advantageous for ongoing real-time or near-real-time ingestion of data from various sources for general data access and visualization, and also allow for complex, data rich calculations by leveraging expansive networks and virtually unlimited compute power. A web-based framework offers a natural architecture for such endeavors, as access to compute nodes through auto-scaling and dynamic frameworks enables speedy data manipulation and unlimited access to any data set that is made available via an http request. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOC-WMF - A Generic Model for Assessment of Waste Disposal Facilities - 19278
Numerical models and computer codes play an important role in the safety assessment of nuclear waste disposal facilities, as well as in the regulatory review of proponents' safety assessments. An important part of a safety assessment is the radiation dose calculation. This paper presents a computer code called DOC-WMF for calculating radiation dose from nuclear waste disposal facilities. DOC-WMF is a generic code that could be used for dose calculations for deep geological or near surface disposal facilities of nuclear wastes. DOC-WMF is much faster than complicated 3-D numerical models in terms of computational speed since the model uses the commercial code GoldSim as the computation engine which is based on analytical solutions for contaminant transport. As a result, it enables a user to quickly assess the dose consequences of multiple options or scenarios for a nuclear waste disposal facility. DOC-WMF was adapted from, and an improvement to, the Scoping of Options and Analyzing Risk (SOAR) model developed by the United States Nuclear Regulatory Commission (US NRC). A key improvement over the SOAR model is that DOC-WMF allows the calculation of dose contributions from other pathways such as food ingestion and air inhalation in addition to the drinking water pathway which is the sole dose contribution considered in the SOAR model. DOC-WMF also allows for: the consideration of 55 radionuclides with option to add more if required; the choice of source release method; various pathways to the biosphere; and dose calculations including an extended array of exposure pathways. In addition, DOC-WMF can simulate more complex hydrogeological settings and waste forms than SOAR does. DOC-WMF was compared against known analytical solutions for verification. It was then applied to two test cases and the results were compared. The first was a hypothetical deep geological disposal repository. The second test case was a near-surface nuclear waste disposal facility. DOC-WMF independently modeled these two test cases and achieved similar results as the more complicated numerical models did. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Development of Concentration Ratios and Transfer Factors for Human and Ecological Probabilistic Performance Assessments - 19781
Human and ecological risk assessments utilize concentration ratios and transfer factors to calculate contaminant concentrations in plant and animal tissues in equilibrium with soil or water (concentration ratios) or based on an animal's contaminant intake from various media (transfer factors). These ratios and factors are used to evaluate human dose via food ingestion pathways and to evaluate ecological dose to an organism. In a probabilistic performance assessment, concentration ratio and transfer factor distributions are developed for every element, and these distributions are applied across the spatial and temporal domain of the assessment. As a result, it is necessary to scale the underlying data distributions by applying the central limit theorem to develop appropriate distributions of the mean for the temporal and spatial scale of the model. Herein we discuss the methodologies for identifying and ranking references, and how to develop statistical distributions of concentration ratios and transfer factors for probabilistic performance assessment models. We also discuss factors that could be pertinent to differences when selecting references and developing distributions for human versus ecological risk assessment scenarios. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
Preliminary Dose Assessment during Dismantling Biological Shield of Kori Unit-1
After Fukushima nuclear power plant accident at 2011, many counties decided to limit or hold operation and construction of nuclear power plant (NPP). Kori NPP unit-1, which was commissioned at 1978 and expected to operate until June 2017, was decided to stop its operation considering design life, political and public aspect in Korea while it was thought to be one of the reactors which had been affected by such nuclear accident. Accordingly, Korea Hydro and Nuclear Power Company, who is owner of Kori NPP unit-1, decided not to apply its life extension and is planning to prepare for the decommissioning. To establish decommissioning plan, it is needed to evaluate and secure the various safety factors including radiological safety. The biological shield has been neutron-activated by fission reaction during the operation of the reactor and various kinds of radionuclide including {sup 3}H, {sup 60}Co, {sup 55}Fe, and {sup 152}Eu are generated in the concrete. Thus, the biological shield dismantling worker will be exposed due to radiation from radioactive concrete and aerosol from its cutting. In this paper, the effective dose of the worker expected to dismantle biological shield is analyzed preliminarily. The dose assessment is analyzed on the external exposure from direct radiation and internal exposure due to inhalation and ingestion for the workers divided into three types.
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
A Processing and Analytics System for Microscopy Data Workflows: The Pycroscopy Ecosystem of Packages
Major advancements in fields as diverse as biology and quantum computing have relied on a multitude of microscopy techniques. Despite the considerable proliferation of these instruments, significant bottlenecks remain in terms of processing, analysis, storage, and retrieval of the acquired datasets. Aside from lack of file standards, individual domain-specific analysis packages are often disjoint from the underlying datasets, and thus keeping track of analysis and processing steps remains tedious for the end-user, hampering reproducibility. Here, in this study, the pycroscopy ecosystem of packages is introduced, an open-source python-based ecosystem underpinned by a common data model. The data model, termed the N-dimensional spectral imaging data format, is realized in pycroscopy's sidpy package. This package is built on top of dask arrays, thus leveraging dask array attributes, but expanding them to accelerate microscopy relevant analysis and visualization. Several examples of the use of the pycroscopy ecosystem to create workflows for data ingestion and analysis of scanning transmission electron microscopy (STEM) and scanning probe microscopy data are shown. Adoption of such standardized routines will be critical to usher in the next generation of autonomous instruments where processing, computation, and meta-data storage will be critical to overall experimental operations.
97 MATHEMATICS AND COMPUTING↗
Smart connected worker edge platform for smart manufacturing: Part 1—Architecture and platform design
Abstract The challenge of sustainably producing goods and services for healthy living on a healthy planet requires simultaneous consideration of economic, societal, and environmental dimensions in manufacturing. Enabling technology for data driven manufacturing paradigms like Smart Manufacturing (a.k.a. Industry 4.0) serve as the technological backbone from which sustainable approaches to manufacturing can be implemented. Unfortunately, these technologies are typically associated with broader and deeper factory automation that is often too expensive and complex for the small and medium sized manufacturers (SMMs) that comprise the majority of manufacturing business in the USA and for whom their most valuable asset are the people whose jobs automation while replace. This paper describes an edge intelligent platform to integrate internet‐of‐things technologies with computing hardware, software, computational workflows for machine learning, and data ingestion, enabling SMMs to transition into smart manufacturing paradigms by leveraging the intelligence of their people. The platform leverages consumer grade electronics and sensors (affordable and portable), customized software with open source software packages (accessible), and existing communication network infrastructures (scalable). The software systems are implemented via Kubernetes orchestration of Docker containerization to ensure scalability and programmability. The platform is adaptive via computational workflow engines that produce information from data by processing with low‐cost edge computing devices while efficiently accessing resources of cloud servers as needed. The proposed edge platform connects workers to technological resources that provide computational intelligence (i.e., silicon‐based sensing and computation for data collection and contextualization) to enable decision making at the edge of advanced manufacturing.
Kim, Yoon G.↗