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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2010

Recent Experiences of the NASA Engineering and Safety Center (NESC) GN and C Technical Discipline Team (TDT)

The NASA Engineering and Safety Center (NESC), initially formed in 2003, is an independently funded NASA Program whose dedicated team of technical experts provides objective engineering and safety assessments of critical, high risk projects. The GN&C Technical Discipline Team (TDT) is one of fifteen such discipline-focused teams within the NESC organization. The TDT membership is composed of GN&C specialists from across NASA and its partner organizations in other government agencies, industry, national laboratories, and universities. This paper will briefly define the vision, mission, and purpose of the NESC organization. The role of the GN&C TDT will then be described in detail along with an overview of how this team operates and engages in its objective engineering and safety assessments of critical NASA projects. This paper will then describe selected recent experiences, over the period 2007 to present, of the GN&C TDT in which they directly performed or supported a wide variety of NESC assessments and consultations.

Dennehy, Cornelius J.↗
NASA NTRS2011

Energy Storage Project

NASA's Exploration Technology Development Program funded the Energy Storage Project to develop battery and fuel cell technology to meet the expected energy storage needs of the Constellation Program for human exploration. Technology needs were determined by architecture studies and risk assessments conducted by the Constellation Program, focused on a mission for a long-duration lunar outpost. Critical energy storage needs were identified as batteries for EVA suits, surface mobility systems, and a lander ascent stage; fuel cells for the lander and mobility systems; and a regenerative fuel cell for surface power. To address these needs, the Energy Storage Project developed advanced lithium-ion battery technology, targeting cell-level safety and very high specific energy and energy density. Key accomplishments include the development of silicon composite anodes, lithiated-mixed-metal-oxide cathodes, low-flammability electrolytes, and cell-incorporated safety devices that promise to substantially improve battery performance while providing a high level of safety. The project also developed "non-flow-through" proton-exchange-membrane fuel cell stacks. The primary advantage of this technology set is the reduction of ancillary parts in the balance-of-plant--fewer pumps, separators and related components should result in fewer failure modes and hence a higher probability of achieving very reliable operation, and reduced parasitic power losses enable smaller reactant tanks and therefore systems with lower mass and volume. Key accomplishments include the fabrication and testing of several robust, small-scale nonflow-through fuel cell stacks that have demonstrated proof-of-concept. This report summarizes the project s goals, objectives, technical accomplishments, and risk assessments. A bibliography spanning the life of the project is also included.

Mercer, Carolyn R.↗
NASA NTRS1993

The impact of active controls technology on the structural integrity of aeronautical vehicles

The findings of an investigation conducted under the auspices of The Technical Cooperation Program (TTCP) to assess the impact of active controls technology on the structural integrity of aeronautical vehicles and to evaluate the present state-of-the-art for predicting loads caused by a flight-control system modification and the resulting change in the fatigue life of the flight vehicle are summarized. Important points concerning structural technology considerations implicit in applying active controls technology in new aircraft are summarized. These points are well founded and based upon information received from within the aerospace industry and government laboratories, acquired by sponsoring workshops which brought together experts from contributing and interacting technical disciplines, and obtained by conducting a case study to independently assess the state of the technology. The paper concludes that communication between technical disciplines is absolutely essential in the design of future high performance aircraft.

Noll, Thomas E.↗
NASA NTRS2010

Aeroelasticity Benchmark Assessment: Subsonic Fixed Wing Program

The fundamental technical challenge in computational aeroelasticity is the accurate prediction of unsteady aerodynamic phenomena and the effect on the aeroelastic response of a vehicle. Currently, a benchmarking standard for use in validating the accuracy of computational aeroelasticity codes does not exist. Many aeroelastic data sets have been obtained in wind-tunnel and flight testing throughout the world; however, none have been globally presented or accepted as an ideal data set. There are numerous reasons for this. One reason is that often, such aeroelastic data sets focus on the aeroelastic phenomena alone (flutter, for example) and do not contain associated information such as unsteady pressures and time-correlated structural dynamic deflections. Other available data sets focus solely on the unsteady pressures and do not address the aeroelastic phenomena. Other discrepancies can include omission of relevant data, such as flutter frequency and / or the acquisition of only qualitative deflection data. In addition to these content deficiencies, all of the available data sets present both experimental and computational technical challenges. Experimental issues include facility influences, nonlinearities beyond those being modeled, and data processing. From the computational perspective, technical challenges include modeling geometric complexities, coupling between the flow and the structure, grid issues, and boundary conditions. The Aeroelasticity Benchmark Assessment task seeks to examine the existing potential experimental data sets and ultimately choose the one that is viewed as the most suitable for computational benchmarking. An initial computational evaluation of that configuration will then be performed using the Langley-developed computational fluid dynamics (CFD) software FUN3D1 as part of its code validation process. In addition to the benchmarking activity, this task also includes an examination of future research directions. Researchers within the Aeroelasticity Branch will examine other experimental efforts within the Subsonic Fixed Wing (SFW) program (such as testing of the NASA Common Research Model (CRM)) and other NASA programs and assess aeroelasticity issues and research topics.

Florance, Jennifer P.↗
NASA NTRS1977

Automated array assembly task, phase 1

An assessment of state-of-the-art technologies that are applicable to silicon solar cell and solar cell module fabrication is provided. The assessment consists of a technical feasibility evaluation and a cost projection for high-volume production of silicon solar cell modules. The cost projection was approached from two directions; a design-to-cost analysis assigned cost goals to each major process element in the fabrication scheme, and a cost analysis built up projected costs for alternate technologies for each process element. A technical evaluation was used in combination with the cost analysis to identify a baseline low cost process. A novel approach to metal pattern design based on minimum power loss was developed. These design equations were used as a tool in the evaluation of metallization technologies.

Carbajal, B. G.↗
NASA NTRS1977

Automated array assembly task, phase 1

State-of-the-art technologies applicable to silicon solar cell and solar cell module fabrication were assessed. The assessment consisted of a technical feasibility evaluation and a cost projection for high volume production of solar cell modules. Design equations based on minimum power loss were used as a tool in the evaluation of metallization technologies. A solar cell process sensitivity study using models, computer calculations, and experimental data was used to identify process step variation and cell output variation correlations.

Carbajal, B. G.↗
NASA NTRS1978

King 2 2519 ATM residual gyros: Reestablishing 5 year life requirements

The technical expertise required to assess the condition of the residual ATM 2519 Singer gyros is discussed. Past build history records, past performance characteristics, and recommendations for particular tests (which were performed by NASA personnel) are summarized. Test results are analyzed. A study of motor performance data and recommendations concerning gyro spin bearing life was performed. A method of reestablishing potential reliability of the bearing for the 5-year life requirement of the power module is also included.

Kayal, B.↗
NASA NTRS1979

Satellite Power Systems (SPS): Concept development and evaluation program: Preliminary assessment

A preliminary assessment of a potential Satellite Power System (SPS) is provided. The assessment includes discussion of technical and economic feasibility; the effects of microwave power transmission beams on biological, ecological, and electromagnetic systems; the impact of SPS construction, deployment, and operations on the biosphere and on society; and the merits of SPS compared to other future energy alternatives.

Source record↗
NASA NTRS1981

AgRISTARS. Preliminary technical results review of FY81 experiments, volume 2: Fiscal year 1981/1982 "corn and soybeans pilot" experiment

The performance of the technology exhibited significant proportion estimation errors, specifically, high mean error in both corn and soybeans area estimation. The data systems, technical approaches, and data assessment of the pilot experiment were reviewed. Results of proportion estimations procedure performance evaluations, and sensitivity evaluations are presented. The role of the pilot experiment in foreign technology development is discussed.

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NASA NTRS1982

From Lindbergh to Columbia - The Space Shuttle

An effort to gage the level of maturation of space transportation development signalled by the advent of the Shuttle is attempted. Analogy is drawn to the successful crossing of the Atlantic Ocean by Charles Lindbergh, an event which established the feasibility of routine air transport over long distances. A positive shift in public confidence is expected to arrive by recalling the favorable news coverage which resulted after two or three flights by the Wright brothers at Kitty Hawk in 1908. The evolution of modern airports is taken as an indication of the kind of growth in facilities which may shortly be required due to operational space transportation systems. The arrival of normal operations of humans-to-space and return in reuseable vehicles is seen as a benchmark for a time when certain global assessments of social and technical requirements for the continued existence and progress of human civilization on earth and into space must be made.

Lovelace, A.↗
NASA NTRS1991

Impact of active controls technology on structural integrity

This paper summarizes the findings of The Technical Cooperation Program to assess the impact of active controls technology on the structural integrity of aeronautical vehicles and to evaluate the present state-of-the-art for predicting the loads caused by a flight-control system modification and the resulting change in the fatigue life of the flight vehicle. The potential for active controls to adversely affect structural integrity is described, and load predictions obtained using two state-of-the-art analytical methods are given.

Noll, Thomas↗
NASA NTRS1990

Autonomous Rendezvous and Docking Conference, volume 2

Autonomous Rendezvous and Docking (ARD) will be a requirement for future space programs. Clear examples include satellite servicing, repair, recovery, and reboost in the near term, and the longer range lunar and planetary exploration programs. ARD will permit more aggressive unmanned space activities, while providing a valuable operational capability for manned missions. The purpose of the conference is to identify the technologies required for an on-orbit demonstration of ARD, assess the maturity of those technologies, and provide the necessary insight for a quality assessment of programmatic management, technical, schedule, and cost risks.

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NASA NTRS1990

Autonomous Rendezvous and Docking Conference, volume 3

This document consists of the presentation submitted at the Autonomous Rendezvous and Docking (ARD) Conference. The document 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 ARD, assess the maturity of these technologies, and provide the necessary insight for a quality assessment of programmatic management, technical, schedule, and cost risks.

Source record↗
NASA NTRS1991

The Extreme Ultraviolet Explorer science instruments development - Lessons learned

The science instruments development project for the Extreme Ultraviolet Explorer (EUVE) satellite is reviewed. Issues discussed include the philosophical basis of the program, the establishment of a tight development team, the approach to planning and phasing activities, the handling of the most difficult technical problems, and the assessment of the work done during the preimplemntation period of the project.

Malina, Roger F.↗
NASA NTRS2000

A Low Cost, Self-Acting, Liquid Hydrogen Boil-Off Recovery System

PROJECT SUMMARY. 1 PROJECT OBJECTIVES. Detail Design. Final Analysis. Hardware Procurement. Component Tests. System Tests..Prototype Tests. 2. WORK PERFORMED. Detail Design. Final Analysis. Hardware Procurement. Component Tests. System Tests. Prototype Tests. 3. Results obtained. Detail Design. Final Analysis. Hardware Procurement. Component Tests. System Tests. Prototype Tests. 5. TECHNICAL MERIT AND FEASIBILITY ASSESSMENT. 6. APPENDIX A: SIZE DETAIL DRAWINGS. 7. APPENDIX B: CONSULTANTS SENSITIVITY STUDY. 8. APPENDIX C: CONSULTANTS REPORT. ROTORDYNAMIC ANALYSIS 9. SF298 REPORT DOCUMENTATION PAGE.

Pelfrey, Joy w.↗
NASA NTRS2005

Technical Consultation of the Hubble Space Telescope (HST) System Health Assessment: Analysis of HST Health

The NESC conducted an abridged independent examination of available information and personnel interviews to evaluate the current and anticipated state of the spacecraft subsystems and the parameters that describe the HST's health. These examinations included the projected timeliness of a robotic SM and whether the GSFC baseline concept is likely to provide the capability to extend the useful scientific life of the HST by an additional 5 years. The NESC team collected a broad spectrum of pertinent HST Program analyses, reports, briefings, and the results of the IPAO and the Aerospace Corporation AOA assessments as they relate to the degradation of the HST s health. This review included the state of the HST subsystems having the potential to impact the viability of the HST, but will not be serviced under the baseline robotic SM.

Gentz, Steven J.↗
NASA NTRS2008

Seven Key Principles of Program and Project Success: A Best Practices Survey

The National Aeronautics and Space Administration (NASA) Organization Design Team (ODT), consisting of 20 seasoned program and project managers and systems engineers from a broad spectrum of the aerospace industry, academia, and government, was formed to support the Next Generation Launch Technology (NGLT) Program and the Constellation Systems Program. The purpose of the ODT was to investigate organizational factors that can lead to success or failure of complex government programs, and to identify tools and methods for the design, modeling, and analysis of new and more-efficient program and project organizations. The ODT conducted a series of workshops featuring invited lectures from seasoned program and project managers representing 25 significant technical programs spanning 50 years of experience. The result was the identification of seven key principles of program success that can be used to help design and operate future program organizations. This paper presents the success principles and examples of best practices that can significantly improve the design of program, project, and performing technical line organizations, the assessment of workforce needs and organization performance, and the execution of programs and projects.

Bilardo, Vincent J.↗
NASA NTRS2006

Hydrogen and Storage Initiatives at the NASA JSC White Sands Test Facility

NASA WSTF Hydrogen Activities: a) Aerospace Test; b) System Certification & Verification; c) Component, System, & Facility Hazard Assessment; d) Safety Training Technical Transfer: a) Development of Voluntary Consensus Standards and Practices; b) Support of National Hydrogen Infrastructure Development.

Maes, Miguel↗