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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 505 records · Page 28
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Technical, Economic, Energetic, and Environmental Evaluation of Pretreatment Strategies for Scaling Control in Brackish Water Desalination Brine Treatment

Effective pretreatment is essential for achieving long-term stable operation and high water recovery during the desalination of alternative waters. This study developed a process modeling approach for technical, economic, energetic, and environmental assessments of pretreatment technologies to identify the impacts of each technology treating brackish water desalination brine with high scaling propensity. The model simulations evaluated individual pretreatment technologies, including chemical softening (CS), chemical coagulation (CC), electrocoagulation (EC), and ion exchange (IX). In addition, combinations of these pretreatment technologies aiming at the effective reduction of key scaling constituents such as hardness and silica were investigated. The three evaluation parameters in this assessment consist of levelized cost of water (LCOW, $/m 3 ), specific energy consumption and cumulative energy demand (SEC|CED, kWh/m 3 ), and carbon dioxide emissions (CO 2 , kg CO 2-eq /m 3 ). The case study evaluated in this work was the desalination brine from the Kay Bailey Hutchison Desalination Plant (KBHDP) with a total dissolved solids (TDS) concentration of 11,000 mg/L and rich in hardness and silica. The evaluation of individual pretreatment units from the highest to lowest LCOW, SEC|CED, and CO 2 emissions in the KBHDP brine was IX > CS > EC > CC, CS > IX > EC > CC, and CC > CS > EC > IX, respectively. In the case of pretreatment combinations for the KBHDP, the EC + IX treatment combination was shown to be the best in terms of the LCOW and CO 2 emissions. The modeling and evaluation of these pretreatment units provide valuable guidance on the selection of cost-effective, energy-efficient, and environmentally sustainable pretreatment technologies tailored to desalination brine applications for minimal- or zero-liquid discharge.

14 SOLAR ENERGY↗
NASA NTRS1979

The 25 W power module evolution study. Part 3: Conceptual designs for power module evolution. Volume 5: Mission accommodations

The capability of the 25 kW power module to conduct representative missions which include Earth, solar, and stellar observation as well as zero-gravity experiments was assessed. Mission accommodations and related technical characteristics of the various operating modes are summarized. The minimum power module provides a substantial mission support on sortie flights. The addition of an attitude sensor is required for free-flying pointing missions.

Source record↗
NASA NTRS1980

Risk to the public from carbon fibers released in civil aircraft accidents

Because carbon fibers are strong, stiff, and lightweight, they are attractive for use in composite structures. Because they also have high electrical conductivity, free carbon fibers settling on electrical conductors can cause malfunctions. If released from the composite by burning, the fibers may become a hazard to exposed electrical and electronic equipment. As part of a Federal study of the potential hazard associated with the use of carbon fibers, NASA assessed the public risk associated with crash fire accidents of civil aircraft. The NASA study projected a dramatic increase in the use of carbon composites in civil aircraft and developed technical data to support the risk assessment. Personal injury was found to be extremely unlikely. In 1993, the year chosen as a focus for the study, the expected annual cost of damage caused by released carbon fibers is only $1000. Even the worst-case carbon fiber incident simulated (costing $178,000 once in 34,000 years) was relatively low-cost compared with the usual air transport accident cost. On the basis of these observations, the NASA study concluded that exploitation of composites should continue, that additional protection of avionics is unnecessary, and that development of alternate materials specifically to overcome this problem is not justified.

Source record↗
NASA NTRS1983

High-temperature optically activated GaAs power switching for aircraft digital electronic control

Gallium arsenide high-temperature devices were fabricated and assembled into an optically activated pulse-width-modulated power control for a torque motor typical of the kinds used in jet engine actuators. A bipolar heterojunction phototransistor with gallium aluminum arsenide emitter/window, a gallium arsenide junction field-effect power transistor and a gallium arsenide transient protection diode were designed and fabricated. A high-temperature fiber optic/phototransistor coupling scheme was implemented. The devices assembled into the demonstrator were successfully tested at 250 C, proving the feasibility of actuator-located switching of control power using optical signals transmitted by fibers. Assessments of the efficiency and technical merits were made for extension of this high-temperature technology to local conversion of optical power to electrical power and its control at levels useful for driving actuators. Optical power sources included in the comparisons were an infrared light-emitting diode, an injection laser diode, tungsten-halogen lamps and arc lamps. Optical-to-electrical power conversion was limited to photovoltaics located at the actuator. Impedance matching of the photovoltaic array to the load was considered over the full temperature range, -55 C to 260 C. Loss of photovoltaic efficiency at higher temperatures was taken into account. Serious losses in efficiency are: (1) in the optical source and the cooling which they may require in the assumed 125 C ambient, (2) in the decreased conversion efficiency of the gallium arsenide photovoltaic at 260 C, and (3) in impedance matching. Practical systems require improvements in these areas.

Berak, J. M.↗
NASA NTRS1990

Autonomous Rendezvous and Docking Conference, volume 1

This document consists of the presentation submitted at the Autonomous Rendezvous and Docking (ARD) Conference. It contains three volumes: ARD hardware technology; ARD software technology; and ARD operations. The purpose of this conference is to identify the technologies required for an on orbit demonstration of the ARD, assess the maturity of these technologies, and provide the necessary insight for a quality assessment of the programmatic management, technical, schedule, and cost risks.

Source record↗
NASA NTRS1992

Total Quality Management in Space Shuttle Main Engine manufacturing

The Total Quality Management (TQM) philosophy developed in the Marshall Space Flight Center (MSFC) is briefly reviewed and the ongoing TQM implementation effort which is being pursued through the continuous improvement (CI) process is discussed. TQM is based on organizational excellence which integrates the new supportive culture with the technical tools necessary to identify, assess, and correct manufacturing processes. Particular attention is given to the prime contractor's change to the organizational excellence management philosophy in SSME manufacturing facilities.

Ding, J.↗
NASA NTRS1993

A system architecture for an advanced Canadian wideband mobile satellite system

In this paper, the system architecture for an advanced Canadian ka-band geostationary mobile satellite system is described, utilizing hopping spot beams to support a 256 kbps wideband service for both N-ISDN and packet-switched interconnectivity to small briefcase-size portable and mobile terminals. An assessment is given of the technical feasibility of the satellite payload and terminal design in the post year 2000 timeframe. The satellite payload includes regeneration and on-board switching to permit single hop interconnectivity between mobile terminals. The mobile terminal requires antenna tracking and platform stabilization to ensure acquisition of the satellite signal. The potential user applications targeted for this wideband service includes: home-office, multimedia, desk-top (PC) videoconferencing, digital audio broadcasting, single and multi-user personal communications.

Takats, P.↗
NASA NTRS2001

Use of System Safety Risk Assessments for the Space Shuttle Reusable Solid Rocket Motor (RSRM)

This paper discusses the System Safety approach used to assess risk for the Space Shuttle Reusable Solid Rocket Motor (RSRM). Previous to the first RSRM flight in the fall of 1988, all systems were analyzed extensively to assure that hazards were identified, assessed and that the baseline risk was understood and appropriately communicated. Since the original RSRM baseline was established, Thiokol and NASA have implemented a number of initiatives that have further improved the RSRM. The robust design, completion of rigorous testing and flight success of the RSRM has resulted in a wise reluctance to make changes. One of the primary assessments required to accompany the documentation of each proposed change and aid in the decision making process is a risk assessment. Documentation supporting proposed changes, including the risk assessments from System Safety, are reviewed and assessed by Thiokol and NASA technical management. After thorough consideration, approved changes are implemented adding improvements to and reducing risk of the Space Shuttle RSRM.

Greenhalgh, Phillip O.↗
NASA NTRS2005

The Small Aircraft Transportation System Higher Volume Operations (SATS HVO) Flight Experiment

This paper provides a summary of conclusions from the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) Flight Experiment which NASA conducted to determine pilot acceptability of the HVO concept for normal conditions. The SATS HVO concept improves efficiency at non-towered, non-radar airports in Instrument Meteorological Conditions (IMC) while achieving a level of safety equal to today s system. Reported are results from flight experiment data that indicate that the SATS HVO concept is viable. The success of the SATS HVO concept is based on acceptable pilot workload, performance, and subjective criteria when compared to the procedural control operations in use today at non-towered, non-radar controlled airfields in IMC. The HVO Flight Experiment, flown on NASA's Cirrus SR22, used a subset of the HVO Simulation Experiment scenarios and evaluation pilots in order to validate the simulation experiment results. HVO and Baseline (today s system) scenarios flown included: single aircraft arriving for a GPS non-precision approach; aircraft arriving for the approach with multiple traffic aircraft; and aircraft arriving for the approach with multiple traffic aircraft and then conducting a missed approach. Results reveal that all twelve low-time instrument-rated pilots preferred SATS HVO when compared to current procedural separation operations. These pilots also flew the HVO procedures safely and proficiently without additional workload in comparison to today s system (Baseline). Detailed results of pilot flight technical error, and their subjective assessments of workload and situation awareness are presented in this paper.

Williams, Daniel M.↗
NASA NTRS2010

The Pilot Lunar Geologic Mapping Project: Summary Results and Recommendations from the Copernicus Quadrangle

The first systematic lunar geologic maps were completed at 1:1M scale for the lunar near side during the 1960s using telescopic and Lunar Orbiter (LO) photographs [1-3]. The program under which these maps were completed established precedents for map base, scale, projection, and boundaries in order to avoid widely discrepant products. A variety of geologic maps were subsequently produced for various purposes, including 1:5M scale global maps [4-9] and large scale maps of high scientific interest (including the Apollo landing sites) [10]. Since that time, lunar science has benefitted from an abundance of surface information, including high resolution images and diverse compositional data sets, which have yielded a host of topical planetary investigations. The existing suite of lunar geologic maps and topical studies provide exceptional context in which to unravel the geologic history of the Moon. However, there has been no systematic approach to lunar geologic mapping since the flight of post-Apollo scientific orbiters. Geologic maps provide a spatial and temporal framework wherein observations can be reliably benchmarked and compared. As such, a lack of a systematic mapping program means that modern (post- Apollo) data sets, their scientific ramifications, and the lunar scientists who investigate these data, are all marginalized in regard to geologic mapping. Marginalization weakens the overall understanding of the geologic evolution of the Moon and unnecessarily partitions lunar research. To bridge these deficiencies, we began a pilot geologic mapping project in 2005 as a means to assess the interest, relevance, and technical methods required for a renewed lunar geologic mapping program [11]. Herein, we provide a summary of the pilot geologic mapping project, which focused on the geologic materials and stratigraphic relationships within the Copernicus quadrangle (0-30degN, 0-45degW).

Skinner, J. A., Jr.↗
NASA NTRS2010

The Quest for an OCO (Orbiting Carbon Observatory) Re-Flight

The objective of the OCO (Orbiting Carbon Observatory) mission was to make the first space-based measurements of atmospheric carbon dioxide with the accuracy needed to quantify sources and sinks of this important greenhouse gas. Unfortunately, the observatory was lost as a result of a launch vehicle failure on 24 February 2009. The JPL (Jet Propulsion Laboratory) was directed to assess the options for the re-flight of the OCO instrument and recovery of the carbon-related measurement, and to understand and quantitatively assess the cost, schedule, and technical and programmatic risks of the identified options. The two most likely solutions were (1) a shared platform with the TIRS (Thermal Infrared Sensor) instrument and (2) a dedicated OSC (Orbital Sciences Corporation) LEOStar-2 spacecraft bus similar to that utilized for the original OCO mission. A joint OCO-TIRS mission study was commissioned and two specific options were examined. However, each presented technical challenges that would drive cost. It was determined that the best option was to rebuild the OCO observatory to the extent possible including another LEOStar-2 spacecraft bus. This lowest risk approach leverages the original OCO design and provides the shortest path to launch, which is targeted for no later than the February 2013 timeframe.

carbon↗
NASA NTRS2015

TA-13: Ground and Launch Systems, 2015 NASA Technology Roadmaps

This presentation is a summary of new content contained in the 2015 update of Technology Area-13, Ground and Launch Systems technology roadmap beyond the content contained in the 2010 version. Also included are brief assessments of benefits, alignments, challenges, technical risk and reasonableness, sequencing and timing, and time and effort to achieve goals. This presentation is part of overall presentations of new content only for the 2015 update of the 15 NASA Technology Roadmaps that will be conducted in a public forum managed by the National Research Council on September 28-29, 2015. The 15 roadmaps have already been publically released via the STI process.

decision-making tools↗
NASA NTRS2012

SPS-ALPHA: The First Practical Solar Power Satellite via Arbitrarily Large Phased Array

The vision of delivering solar power to Earth from platforms in space has been known for decades. However, early architectures to accomplish this vision were technically complex and unlikely to prove economically viable. Some of the issues with these earlier solar power satellite (SPS) concepts – particularly involving technical feasibility – were addressed by NASA’s space solar power (SSP) studies and technology research in the mid-to-late 1990s. Despite that progress, ten years ago a number of key technical and economic uncertainties remained. A new SPS concept has been proposed that resolves many, if not all, of those uncertainties: “SPSALPHA” (Solar Power Satellite by means of Arbitrarily Large Phased Array). During 2011-2012 the NASA Innovative Advanced Concepts (NIAC) Program supported a Phase 1 “SPS-ALPHA” project, the goal of which was to establish the technical and economic viability of the SPS-ALPHA concept to an early TRL 3 – analytical proof-of-concept – and provide a framework for further study and technology development. The objectives of this project were to: (1) conduct an initial end-to-end systems analysis of the SPS-ALPHA concept in order to determine its technical feasibility; (2) identify and assess in greater detail the key technology challenges inherent in the architecture (including figures of merit for each critical technology area); (3) conduct an initial evaluation of the economic viability of the concept (as a function of key performance parameters); and, (4) define a preliminary roadmap for the further development of the SPS-ALPHA concept.

Mankins, John↗
NASA NTRS2016

Towards a Methodology and Tooling for Model-Based Probabilistic Risk Assessment (PRA)

A Probabilistic Risk Assessment (PRA) aims to identify and assess potential risks to system technical performance requirements for the purpose of furnishing risk insights into project decisions. PRAs have traditionally been conducted manually using software with an isolated data model. As system complexity rises it becomes difficult to ensure consistency between a PRA, the evolving system design, and other engineering analyses; the techniques for conducting PRAs must evolve to meet this challenge. This work presents progress towards a methodology and tooling for conducting a PRA by leveraging data in the system model, embedded for other purposes and analyses, to conduct a PRA. An approach for identifying the appropriate probabilistic equation for each risk scenario from a standard library is presented, which is a significant step towards the quantification of the likelihood of a risk scenario occurrence. The final calculation of the likelihood of occurrence is left as an item of future work. We also present the development of preliminary tooling to carry out the methodology on a well-formed system model. The information needed to conduct the PRA is embedded in a consistent manner in a system model, so the model-based PRA can be regularly executed as the system model changes. The ability to modify the PRA in concert with lifecycle evolution affords a project the opportunity to track the extent to which system modification impacts compliance with requirements. These aspects of this model-based PRA methodology make it capable of managing risk in increasingly complex technical systems.

Schreiner, Samuel S.↗
NASA NTRS2019

NASA Electrified Aircraft Propulsion Efforts

NASA's broad investments in Electrified Aircraft Propulsion (EAP) are reviewed in this paper. NASA investments are guided by an assessment of potential market impacts, technical key performance parameters, and technology readiness attained through a combination of studies, enabling fundamental research, and flight research. NASA has determined that the impact of EAP varies by market and NASA is considering three markets: national/international, on-demand mobility, and short haul regional air transport. Flight research is underway to demonstrate integrated solutions and inform standards and certification processes. This paper focuses on the vehicle related activities, however there are related NASA activities in air space management and vehicle autonomy activities as well as a breakthrough technology project called the Convergent Aeronautics Solutions Project. A key finding is that sufficient technical advances in key areas have been made which indicate EAP is a viable technology for aircraft. Significant progress has been made to reduce EAP adoption barriers and further work is needed to transition the technology to a commercial product and improve the technology so it is applicable to large transonic aircraft. This paper will review the activities of the Hybrid Gas Electric Subproject of the Advanced Air Transport Technology Project, the Revolutionary Vertical Lift Technology Project, and the X-57 Flight Demonstration Project, and discuss the potential EAP benefits for commercial and military applications.

Jansen, Ralph H.↗
NASA NTRS2024

NASA Engineering and Safety Center Technical Bulletins 2007-2023

An NESC Technical Bulletin captures critical knowledge in the form of new engineering information or best practices in a one-page format that have resulted from NESC independent testing, analysis, and assessments. This document contains all NESC Technical Bulletins from 2007 through 2023.

additive manufacturing, battery, braycote, capacit↗
NASA NTRS2022

Aggregate Risk Tool for Human Space Flight

This tool utilizes Data fusion capabilities developed from the 2020-2022 Information Fusion (IFDA) IRAD to enhance functionality of a Human Spaceflight (HSF) Aggregate Risk Product developed by the JSC Flight Safety Office. The tool compiles and present risk data from multiple Program and Commercial Provider sources to provide a holistic assessment for Program Managers and Technical Authorities to evaluate residual risk prior to HSF Launches. The aggregation, or coupling of risks from multiple sources (Ex: PRA, variances, anomaly data bases, CRM data, technical review board minutes, Hazard Analysis, etc.) identifies areas of elevated risk in components, systems or mission phases that would otherwise be undetected by non-integrated program risk management tools and possesses. Data is then displayed in an interactive user interface/dashboard that enables users to see potential areas of concern requiring more in-depth analysis.

Patrick M Huckaby↗
NASA NTRS2024

Space Based Solar Power

This study evaluates the potential benefits, challenges, and options for NASA to engage with growing global interest in space based solar power (SBSP). Utilizing SBSP entails in-space collection of solar energy, transmission of that energy to one or more stations on Earth, conversion to electricity, and delivery to the grid or to batteries for storage. Experts in both the aerospace and energy sectors are debating the benefits of SBSP as more organizations globally begin SBSP technology development programs. Proponents claim SBSP could deliver large amounts of electricity at competitive prices and with fewer greenhouse gas (GHG) emissions than terrestrial renewable electricity technologies while accelerating development of the space economy. Skeptics say SBSP has no clear development path and would divert billions of dollars from known terrestrial solutions while damaging the environment. While it is generally understood that SBSP is cost prohibitive and technically infeasible today, this study assesses operating SBSP systems in 2050. Part of NASA’s mission is to innovate for the benefit of humanity – it is through this lens that the Agency weighs whether and how to support SBSP development.

Space Based Solar Power↗