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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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This paper is a study of the feasibility of a 35-GHz microwave power transmission system in space. It was found that a dc to dc transmission efficiency better than 50 percent can be achieved over a distance of 50 km by using a transmitting antenna of 20 m in diameter and a receiving antenna of 40 m in diameter. Technology requirements at 35 GHz have been assessed and several stages of development have been proposed.
Abstract This study investigated the feasibility of using conventional casting technique to fabricate refractory wires reinforced superalloy composites. These composites were being developed for advanced rocket engine turbine blades and other high temperature applications operating up to 2000 F. Several types of refractory metal wires such as W- Th, W-Re, Mo-Hf-C and W-HF-C reinforced waspaloy were experimentally cast and heat treated at 2000 F up to 48 hrs. Scanning electron microscope analysis was conducted in regions adjacent to the wire-matrix interface to determine the reaction zone and chemical compatibility resulting from material interdiffusion. It was concluded that fabrication using conventional casting may be feasible because the wire-matrix reaction zone thickness was comparable to similar composites produced by arc-sprayed monotape with hot isostatic pressing technique, Moreover, it was also found that the chemical compatibility could be improved significantly through a slight modification of the superalloy matrix compositions.
This study explored the feasibility of replacing the Galileo spacecraft's plutonium-238 fueled radioisotope thermoelectric generators (RTGs) with solar arrays.
NASA's Exploration and Space Communications projects division recently completed an investigative study, researching the feasibility of integrating optical communications capabilities onto a science-based mission orbiting at Lagrange Point 2 (L2). Optical communications has been demonstrated and integrated into many low-Earth-orbiting missions, however, using the technology as far as L2 needed to be thoroughly researched and proven similarly as efficient as the mission's planned radio frequency (RF) system, but preferably more efficient that the equivalent RF systems. The investigation team was charged with assessing the feasibility of including optical communications on the mission without interfering with its primary science objectives. This came to be known as the "Do No Harm" approach to accommodation. As science and detection technologies become more advanced, data rates and communications requirements continue to evolve. Missions with complex science instruments have a need for more optimized communications capabilities. Optical communications technologies provide NASA and industry missions with increased data rates and quicker response times, allowing scientists to access more data than ever before. Missions utilizing optical communications will have a lighter and more efficient method of transmitting data to users on Earth. The team investigating this opportunity discovered that including an optical communications payload on board the mission to provide a bi-directional link between the spacecraft and Earth-based ground stations is feasible and reaches data rates that are comparable to, and even exceed, the mission's RF system. In the course of their investigation, the team also discovered significant navigation and ranging benefits provided by the optical communications payload (OCP).
The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Former Chanute Air Force Base site in Rantoul, Illinois, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) was contacted to provide technical assistance for this project. The purpose of this study was to assess the site for a possible biopower system installation and estimate the cost, performance, and impacts of different biopower options.
The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the TechCity East Campus site in Kingston, New York, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this study is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.
The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Crazy Horse Landfill site in Salinas, California, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) was contacted to provide technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, operation and maintenance requirements, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.
The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Chino Mine site in Silver City, New Mexico, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.
The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Standard Chlorine of Delaware site in Delaware City, Delaware, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.
The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Former Bethlehem Steel Plant site in Lackawanna, New York, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.
The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Former Fort Ord Army Base (FOAB) site in Marina, California, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.
The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Peru Mill Industrial Park site in the City of Deming, New Mexico, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.
To reduce the geothermal exploration risk, a feasibility study is performed for a deep direct-use system proposed at the West Virginia University (WVU) Morgantown campus. This study applies numerical simulations to investigate reservoir impedance and thermal production. Because of the great depth of the geothermal reservoir, few data are available to characterize reservoir features and properties. As a result, the study focuses on the following three aspects: 1. model choice for predicting reservoir impedance and thermal breakthrough: after investigating three potential models (one single permeability model and two dual permeability models) for flow through fractured rock, it is decided to use single permeability model for further analysis; 2. well placement (horizontal vs. vertical) options: horizontal well placement seems to be more robust to heterogeneity and the impedance is more acceptable; 3. Prediction uncertainty: the most influential parameters are identified using a First-Order-Second-Moment uncertainty propagation analysis, and the uncertain range of the model predictions is estimated by performing a Monte Carlo simulation. Heterogeneity has a large impact on the perdition, therefore, is considered in the predictive model and uncertainty analysis. The numerical model results and uncertainty analysis are used for economic analysis. The dataset submitted here support the described study. Manuscript is submitted to Geothermics, will be linked once paper is accepted.
The feasibility of constructing a solar pond power plant at Davis, California was studied. Site visits, weather data compilation, soil and water analyses, conceptual system design and analyses, a material and equipment market survey, conceptual site layout, and a preliminary cost estimate were studied. It was concluded that a solar pond power plant is technically feasible, but economically unattractive. The relatively small scale of the proposed plant and the high cost of importing salt resulted in a disproportionately high capital investment with respect to the annual energy production capacity of the plant. Cycle optimization and increased plant size would increase the economical attractiveness of the proposed concept.
The U.S. Environmental Protection Agency (EPA) developed the RE-Powering America's Land initiative to reuse contaminated sites for renewable energy generation when aligned with the community's vision for the site. The former American Smelting and Refining Company (Asarco) smelter in East Helena, Montana, was selected for a feasibility study under the initiative. Biomass was chosen as the renewable energy resource based on the wood products industry in the area. Biopower was selected as the technology based on Montana's renewable portfolio standard (RPS) requiring utilities to purchase renewable power.
This feasibility study presents the conceptual design of a spacecraft for performing a series of cryogenic fluid management flight experiments. This spacecraft, the Cryogenic On-Orbit Liquid Depot-Storage, Acquisition, and Transfer (COLD-SAT) satellite, will use liquid hydrogen as the test fluid, be launched on a Delta expendable launch vehicle, and conduct a series of experiments over a two to three month period. These experiments will investigate the physics of subcritical cryogens in the low gravity space environment to characterize their behavior and to correlate the data with analytical and numerical models of in-space cryogenic fluid management systems. Primary technologies addressed by COLD-SAT are: (1) pressure control; (2) chilldown; (3) no-vent fill; (4) liquid acquisition device fill; (5) pressurization; (6) low-g fill and drain; (7) liquid acquisition device expulsion; (8) line chilldown; (9) thermodynamic state control; and (10) fluid dumping.
An innovative millimeter wave diagnostic is proposed to measure the local magnetic field and the edge current as a function of the minor radius in the pedestal region. The idea behind such diagnostic is to localize and characterize a direction of reduced reflectivity at the O-mode cutoff layer. We modeled the wave scattering and mode-conversion processes by means of the finite-element COMSOL Multiphysics code in two dimensions (2D). Sensitivity studies were performed for parameters mocking up DIII-D plasmas. Simulations confirmed the presence of a minimum in reflectivity of an externally injected O-mode beam, and confirmed that this minimum depends on the magnetic field at the cutoff, as expected from the OX mode conversion physics. This study gives confidence in the feasibility of the diagnostic.
Purpose: In room kilovoltage x-ray (kV) imaging provides higher contrast than Megavoltage (MV) imaging with faster acquisition time compared with on-board cone-beam computed tomography (CBCT), thus improving patient setup accuracy and efficiency. In this study we evaluated the clinical feasibility of utilizing kV imaging for whole breast radiation patient setup. Methods: For six breast cancer patients with whole breast treatment plans using two opposed tangential fields, MV-based patient setup was conducted by aligning patient markers with in room lasers and MV portal images. Beam-eye viewed kV images were acquired using Varian OBI system after the set up process. In house software was developed to transfer MLC blocks information overlaying onto kV images to demonstrate the field shape for verification. KV-based patient digital shift was derived by performing rigid registration between kV image and the digitally reconstructed radiography (DRR) to align the bony structure. This digital shift between kV-based and MV-based setup was defined as setup deviation. Results: Six sets of kV images were acquired for breast patients. The mean setup deviation was 2.3mm, 2.2mm and 1.8mm for anterior-posterior, superior-inferior and left-right direction respectively. The average setup deviation magnitude was 4.3±1.7mm for six patients. Patient with large breast had a larger setup deviation (4.4–6.2mm). There was no strong correlation between MV-based shift and setup deviation. Conclusion: A preliminary clinical workflow for kV-based whole breast radiation setup was established and tested. We observed setup deviation of the magnitude below than 5mm. With the benefit of providing higher contrast and MLC block overlaid on the images for treatment field verification, it is feasible to use kV imaging for breast patient setup.