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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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A high level computer programming language and a program library were developed to be used in writing programs for scheduling complex systems such as the space transportation system. The objectives and requirements of the study are summarized and unique features of the specified language and program library are described and related to the why of the objectives and requirements.
In an effort to insure the future development of hypersonic cruise aircraft, the possible vehicle configurations were examined to develop a single-stage-to-orbit hypersonic research vehicle (HRV). Based on the needs of hypersonic research and development, the mission goals and requirements are determined. A body type is chosen. Three modes of propulsion and two liquid rocket fuels are compared, followed by the optimization of the body configuration through aerodynamic, weight, and trajectory studies. A cost analysis is included.
The results of investigations into the application of winglets to the DC-10 aircraft are presented. The DC-10 winglet configuration was developed and its cruise performance determined in a previous investigation. This study included high speed and low speed wind tunnel tests to evaluate aerodynamic characteristics, and a subsonic flutter wind tunnel test with accompanying analysis and evaluation of results. Additionally, a configuration integration study employed the results of the wind tunnel studies to determine the overall impact of the installation of winglets on the DC-10 aircraft. Conclusions derived from the high speed and low speed tests indicate that the winglets had no significant effects on the DC-10 stability characteristics or high speed buffet. It was determined that winglets had a minimal effect on aircraft lift characteristics and improved the low speed aircraft drag under high lift conditions. The winglets affected the DC-10 flutter characteristics by reducing the flutter speed of the basic critical mode and introducing a new critical mode involving outer wing torsion and longitudinal bending. The overall impact of winglets was determined to be of sufficient benefit to merit flight evaluation.
Radiation-resistant modularization techniques for development of wrap-around solar cell - fabrication of modules on thin dielectric material containing printed circuit connections
The results are presented of the second six-month performance period of the Nuclear Electric Propulsion Mission Engineering Study. A brief overview of the program, identifying the study objectives and approach, and a discussion of the program status and schedule are presented. The program results are reviewed and key conclusions to date are summarized. Planned effort for the remainder of the program is reviewed.
The limitations of traditional alloys and the desire for improved performance for components is driving the increased utilization of refractory metals in tile space industry. From advanced propulsion systems to high temperature furnace components for microgravity processing, refractory metals are being used for their high melting temperatures and inherent chemical stability. Techniques have been developed to produce near net shape refractory metal components utilizing vacuum plasma spraying. Material utilization is very high, and laborious machining can be avoided. As-spray formed components have been tested and found to perform adequately. However, increased mechanical and thermal properties are needed. To improve these properties, post processing thermal treatments such as hydrogen sintering and vacuum annealing have been performed. Components formed from alloys of tungsten, rhenium, tantalum, niobium, and molybdenum are discussed and a metallurgical analyses detailing the results are presented. A qualitative comparison of mechanical properties is also included.
Using NASA IIb as a base composition, the effects of five key elements (carbon, tungsten, tantalum, aluminum, and hafnium) on resultant properties were investigated in an effort to optimize the composition and derive new wrought high temperature alloys with improved strength characteristics. A total of nineteen compositions were melted, extruded, and rolled to bar stock using thermomechanical processing. Both full and partial solution heat treatments were developed for the compositions. Tensile properties from room temperature to 1800 deg F, stress and creep rupture properties to 1800 deg F, and thermal stability characteristics were evaluated. NASA IIb-7 exhibited the best response to the partial solution heat treatment for optimum properties up to 1200 deg F. The alloy contained 0.13C, 9.0 Cr, 9.0 Co, 2.0 Mo, 7.5 W, 10.0 Ta, 3.5 Al, 0.75 Ti, 0.02 B, 0.10 Zr, 0.50 V, 1.0 Hf, and balance nickel.
This paper studies the notion of obstacle-avoidance guidance, and investigates the issues in automating this function by considering helicopter nap-of-the-earth (NOE) flight as an example. In particular, it considers a hierarchy of guidance components, including mission planning and obstacle avoidance. Based on this hierarchical breakdown, the functional requirements of obstacle-avoidance guidance are identified. An effort in developing automatic guidance algorithms to meet these requirements is presented, along with the necesssary simulation tools for evaluation of these algorithms.
Gauging the mass of propellants in a tank in low gravity is not a straightforward task because of the uncertainty of the liquid configuration in the tank and the possibility of there being more than one ullage bubble. Several concepts for such a low-gravity gauging system have been proposed, and breadboard or flight-like versions have been tested in normal gravity or even in low gravity, but at present, a flight-proven reliable gauging system is not available. NASA desired a database of the gauging techniques used in current and past vehicles during ascent or under settled conditions, and during short coasting (unpowered) periods, for both cryogenic and storable propellants. Past and current research and development efforts on gauging systems that are believed to be applicable in low-gravity conditions were also desired. This report documents the results of that survey.
This dataset contains grid files for subsurface maps created in GES interpretation software and exported as Zmap formated grid files. Depth values in SSTVD (subsea true vertical depth). The methods used for analysis and a detailed discussion of the results are presented in a paper by McCleery et al., (2018).
Background Papers on COVID-19 are being published at a high rate and concern many different topics. Innovative tools are needed to aid researchers to find patterns in this vast amount of literature to identify subsets of interest in an automated fashion. Objective We present a new online software resource with a friendly user interface that allows users to query and interact with visual representations of relationships between publications. Methods We publicly released an application called PLATIPUS (Publication Literature Analysis and Text Interaction Platform for User Studies) that allows researchers to interact with literature supplied by COVIDScholar via a visual analytics platform. This tool contains standard filtering capabilities based on authors, journals, high-level categories, and various research-specific details via natural language processing and dozens of customizable visualizations that dynamically update from a researcher’s query. Results PLATIPUS is available online and currently links to over 100,000 publications and is still growing. This application has the potential to transform how COVID-19 researchers use public literature to enable their research. Conclusions The PLATIPUS application provides the end user with a variety of ways to search, filter, and visualize over 100,00 COVID-19 publications.</:p>
The program of the Reactor Neutrino Experiments of Turkey includes a small portable Water-based liquid scintillator detector to detect neutrinos from the Akkuyu nuclear power plant, planned to begin operating in 2023. The small near-field detector will weigh about 2-3 tons and will be placed less than 100 meters from the reactor cores. The Reactor Neutrino Experiments of Turkey program also includes a medium-size 30-ton Water-based liquid scintillator detector, which will be placed 1-2 km away from the reactor cores and will be used as a far detector. Both detectors and their responses to neutrino interactions were simulated using a GEANT4-based RAT-PAC simulation package. Here, we will share the technical and physical details of both detectors, and discuss the ongoing R&D effort for neutrino studies in Turkey.
Design of traveling magnetic field electrodeless plasma engine
Voltage and capacity studies of electrolytes for silver-cadmium battery in space application
Silver-cadmium battery - cell tests, separator property changes, gas recombination, negative formation on gas evolution, trickle and constant potential charging, and argentous operation
Determination of thermophysical properties and temperature control techniques in applying melting and solidification of materials to temperature control of space vehicle subsystems
Packaging techniques and systems design for applying solid-to-liquid phase change concept to spacecraft temperature control subsystems
Space thermal control using fusible materials, with analysis of one-dimensional adiabatic system