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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 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
NASA NTRS1999

First NASA/Industry High Speed Research Program Nozzle Symposium

The First High Speed Research (HSR) Nozzle Symposium was hosted by NASA Lewis Research Center on November 17-19, 1992 in Cleveland, Ohio, and was sponsored by the HSR Source Noise Working Group. The purpose of this symposium was to provide a national forum for the government, industry, and university participants in the program to present and discuss important low noise nozzle research results and technology issues related to the development of appropriate nozzles for a commercially viable, environmentally compatible, U.S. High-Speed Civil Transport. The HSR Phase I research program was initiated in FY90 and is approaching the first major milestone (end of FY92) relative to an initial FAR 36 Stage 3 nozzle noise assessment. Significant research results relative to that milestone were presented. The opening session provided a brief overview of the Program and status of the Phase H plan. The next five sessions were technically oriented and highlighted recent significant analytical and experimental accomplishments. The last Session included a panel discussion by the Session Chairs, summarizing the progress seen to date and discussing issues relative to further advances in technology necessary to achieve the Program Goals. Attendance at the Symposium was by invitation only and included only industry, academic, and government participants who are actively involved in the High-Speed Research Program. The technology presented in this meeting is considered commercially sensitive.

Long-Davis, Mary Jo↗
NASA NTRS1994

The SMARTSat redesign study

The original design of the Student Mentored Advanced Research and Technology Satellite (SMARTSat) began in January of 1994. The mission adhered to the guidelines and constraints set forth by the Student Explorer Demonstration Initiative Proposal, which was sponsored by the Universities Space Research Association. This report represents a redesign of that original concept. The main differences include a higher orbit and a three axis stabilization system. Of course, these changes imparted significant effects upon the other subsystems. Outlined in this document are those modifications and it offers some new analyses as well. For each subsystem there is a brief description, followed by relevant design assumptions, a summary of conclusions, and finally all pertinent supporting data and graphs. Towards the end of the report. the important issue of cost is addressed as well. Whenever possible, parametric analyses were made.

Lu, Richard↗
NASA NTRS1997

Propellant Management in Booster and Upper Stage Propulsion Systems

A summary review of some of the technical issues which surround the design of the propulsion systems for Booster and Upper Stage systems are presented. The work focuses on Propellant Geyser, Slosh, and Orientation. A brief description of the concern is given with graphics which help the reader to understand the physics of the situation. The most common solutions to these problems are given with there respective advantages and disadvantages.

Fisher, Mark F.↗
NASA NTRS1995

Systems and Techniques for Identifying and Avoiding Ice

In-flight icing is one of the most difficult aviation weather hazards facing general aviation. Because most aircraft in the general aviation category are not certified for flight into known icing conditions, techniques for identifying and avoiding in-flight ice are important to maintain safety while increasing the utility and dispatch capability which is part of the AGATE vision. This report summarizes a brief study effort which: (1) Reviewed current ice identification, forecasting, and avoidance techniques; (2) Assessed feasibility of improved forecasting and ice avoidance procedures; and (3) Identified key issues for the development of improved capability with regard to in-flight icing.

Hansman, R. John↗
NASA NTRS2016

Case Study: Managing Undergraduate Interns in the Context of Multidisciplinary Projects

Internship opportunities can be immensely beneficial to both the students who pursue them and the labs that employ them. However, optimal results for all stakeholders can be uncertain. Several factors compound this issue. In this case study, the highly multidisciplinary nature of the BioEngineering Instrumentation Group at NASA Ames Research Center has made productively integrating short-term summer interns challenging. In general, taking on more undergraduate interns during a given time period can lead to diminishing returns, particularly if those interns are primarily short-time interns with few long-term senior students present.Introducing a level of industry-style project management processes can help. On the one hand, extreme formality can reduce the enthusiasm that students can bring; also, time constraints on internships make extensive training in formal process an investment with comparatively little return. On the other hand, lack of process can result in many forms of wastage. A moderate, lightweight level of process i.e., simple processes with high payoff to time invested ratios, including processes to effectively handle multidisciplinary issues can yield both a far more efficient lab, and a richer educational experience for the interns. In this case study, we implemented simple processes such as brief weekly stand-up meetings, a standard action item bug tracking process, and deadline-based scheduling with prudent reserves and critical path tracking.To evaluate these steps, several parameters were considered: the number of projects the lab could successfully pursue, the number of interns that could be successfully integrated onto each project, diversity of student intern educational backgrounds, student satisfaction, student understanding of expectations, and student preparation for industry-standard work. Generally, outcomes were enhanced across the board, even with imperfectly implemented processes. Lightweight process implementation is shown to be tremendously effective in a multidisciplinary internship context.

Case Study↗
NASA NTRS2005

STS-114: Discovery L-1 Countdown Status Briefing STS-114/Discovery L-2 Countdown Status Briefing

Bruce Buckingham from NASA Public Affairs introduces Jeff Spaulding, NASA Test Director and Kathy Winters, Shuttle Weather Officer in this L-2 countdown status briefing. Spaulding gives the Space Shuttle launch countdown status before lift-off on July 26th. He expresses that vehicle launch and ground systems are performing well and that there are no significant issues in preparation for the launch. The crew arrival time to the launching pad and the launch window for Discovery is also discussed. He ends his countdown status by expressing that the Discovery Orbiter is the safest Shuttle to date. Kathy Winters gives her weather forecast for the launch day. She presents a satellite picture of tropical storm Franklin and charts showing the STS-114 Tanking Forecast, Launch Forecast, Solid Rocket Booster (SRB) recovery, Continental United States (CONUS) launch, Transoceanic Abort Landing (TAL) launch, 24 and 48 Hour Delay, CONUS 24 and 48 hour delay, and TAL 24 and 48 hr delay. Questions from the news media about the mood of the test engineers as launch day is approached are answered. Jessica Rye from NASA Public Affairs introduces Pete Nikolento, NASA Test Director; Scott Higgenbotham, STS-114 Payload Mission Manager; and Kathy Winters, Space Shuttle Weather Officer in this L-1 Countdown Status Briefing. Nikolento expresses that the completion of the main engine system check-outs and servicing of on-board fuel-cell reactants have been completed. He also talks about pad closeouts and external cryogenic loads prior to launch. Scott Higgenbotham gives the payload status and Kathy Winters talks about her weather forecast for launch. Questions about the ecosensors, TAL sites, weather forecast and thoughts about return to flight are addressed.

Source record↗
NASA NTRS2000

South American Summer Monsoon of 1997/1998 and 1998/1999

It is well known that during El Nino years severe drought occurs in the area of Amazon and northeastern Brazil. According to the linear model result the reduced latent heating over the Amazon may lead to a weaker than normal upper tropospheric Bolivian high. As a result, some studies have suggested a weaker South American summer monsoon (SASM) during El Nino years. Using re-analysis. Zhou and Lau data found a statistically significant positive correlation between the tropical eastern Pacific sea surface temperature (SST) and the strength of low-level jet (LLJ) along the eastern foothills of the tropical-subtropical Andes. Douglas also showed a strong LLJ at Santa Cruz, Bolivia during a special pilot balloon observation period in 1997/98 El Nino austral summer. Since this LLJ is an integral part of the monsoon system in the summertime, these results indicated that SASM could be stronger than normal in El Nino years. To clarify this issue, we conducted an investigation on SASM anomaly in the recent ENSO event of 1997/98 El Nino and 1998/99 La Nina In the following we first give a brief review on SASM and the interannual variability of summer rainfall over South America. Then, the impact of 1997-99 ENSO on the South American regional thermal structure and its dynamical consequences to SASM will be discussed.

Lau, William K.-M.↗
NASA NTRS2002

Sliding-Mode Control Applied for Robust Control of a Highly Unstable Aircraft

An investigation into the application of an observer based sliding mode controller for robust control of a highly unstable aircraft and methods of compensating for actuator dynamics is performed. After a brief overview of some reconfigurable controllers, sliding mode control (SMC) is selected because of its invariance properties and lack of need for parameter identification. SMC is reviewed and issues with parasitic dynamics, which cause system instability, are addressed. Utilizing sliding manifold boundary layers, the nonlinear control is converted to a linear control and sliding manifold design is performed in the frequency domain. An additional feedback form of model reference hedging is employed which is similar to a prefilter and has large benefits to system performance. The effects of inclusion of actuator dynamics into the designed plant is heavily investigated. Multiple Simulink models of the full longitudinal dynamics and wing deflection modes of the forward swept aero elastic vehicle (FSAV) are constructed. Additionally a linear state space models to analyze effects from various system parameters. The FSAV has a pole at +7 rad/sec and is non-minimum phase. The use of 'model actuators' in the feedback path, and varying there design, is heavily investigated for the resulting effects on plant robustness and tolerance to actuator failure. The use of redundant actuators is also explored and improved robustness is shown. All models are simulated with severe failure and excellent tracking, and task dependent handling qualities, and low pilot induced oscillation tendency is shown.

Vetter, Travis Kenneth↗
NASA NTRS2007

CIRA: Cooperative Institute for Research in the Atmosphere Newsletter, Volume 28, Fall 2007

The articles in this issue of the Cooperative Institute for Research in the Atmosphere (CIRA) Newsletter are: "Unmanned Aerial Systems: An Overview of NOAA's Unmanned Aircraft System Program," "International Activities: Weather Briefings and Training Via the Internet," "Cloudsat's One-Year Anniversary: An Abundance of Exciting New Cloud Observations," and "The Migration of NCAR'S Auto-Nowcaster into NWS AWIPS."

McInnis-Efaw, Mary↗
NASA NTRS2011

Compilation and Review of Supersonic Business Jet Studies from 1963 through 1995

This document provides a compilation of all known supersonic business jet studies/activities conducted from 1963 through 1995 by university, industry and the NASA. First, an overview is provided which chronologically displays all known supersonic business jet studies/activities conducted by universities, industry, and the NASA along with the key features of the study vehicles relative to configuration, planform, operation parameters, and the source of study. This is followed by a brief description of each study along with some comments on the study. Mention will be made as to whether the studies addressed cost, market needs, and the environmental issues of airport-community noise, sonic boom, and ozone.

Maglieri, Domenic J.↗
NASA NTRS2010

Toward Establishing a Realistic Benchmark for Airframe Noise Research: Issues and Challenges

The availability of realistic benchmark configurations is essential to enable the validation of current Computational Aeroacoustic (CAA) methodologies and to further the development of new ideas and concepts that will foster the technologies of the next generation of CAA tools. The selection of a real-world configuration, the subsequent design and fabrication of an appropriate model for testing, and the acquisition of the necessarily comprehensive aeroacoustic data base are critical steps that demand great care and attention. In this paper, a brief account of the nose landing-gear configuration, being proposed jointly by NASA and the Gulfstream Aerospace Company as an airframe noise benchmark, is provided. The underlying thought processes and the resulting building block steps that were taken during the development of this benchmark case are given. Resolution of critical, yet conflicting issues is discussed - the desire to maintain geometric fidelity versus model modifications required to accommodate instrumentation; balancing model scale size versus Reynolds number effects; and time, cost, and facility availability versus important parameters like surface finish and installation effects. The decisions taken during the experimental phase of a study can significantly affect the ability of a CAA calculation to reproduce the prevalent flow conditions and associated measurements. For the nose landing gear, the most critical of such issues are highlighted and the compromises made to resolve them are discussed. The results of these compromises will be summarized by examining the positive attributes and shortcomings of this particular benchmark case.

Khorrami, Mehdi R.↗
NASA NTRS1978

A review of NASA-sponsored technology assessment projects

Recent technology assessment studies sponsored by NASA are reviewed, and a summary of the technical results as well as a critique of the methodologies are presented. The reviews include Assessment of Lighter-Than-Air Technology, Technology Assessment of Portable Energy RDT&P, Technology Assessment of Future Intercity Passenger Transportation Systems, and Technology Assessment of Space Disposal of Radioactive Nuclear Waste. The use of workshops has been introduced as a unique element of some of these assessments. Also included in this report is a brief synopsis of a method of quantifying opinions obtained through such group interactions. Representative of the current technology assessments, these studies cover a broad range of socio-political factors and issues in greater depth than previously considered in NASA sponsored studies. In addition to the lessons learned through the conduct of these studies, a few suggestions for improving the effectiveness of future technology assessments are provided.

Mascy, A. C.↗
NASA NTRS1991

An investigation of air transportation technology at the Massachusetts Institute of Technology, 1990-1991

Brief summaries are given of research activities at the Massachusetts Institute of Technology (MIT) under the sponsorship of the FAA/NASA Joint University Program. Topics covered include hazard assessment and cockpit presentation issues for microburst alerting systems; the situational awareness effect of automated air traffic control (ATC) datalink clearance amendments; a graphical simulation system for adaptive, automated approach spacing; an expert system for temporal planning with application to runway configuration management; deterministic multi-zone ice accretion modeling; alert generation and cockpit presentation for an integrated microburst alerting system; and passive infrared ice detection for helicopter applications.

Simpson, Robert W.↗
NASA NTRS1993

Use of infrared telemetry as part of a nonintrusive inflight data collection system to collect human factors data

The objective of this paper is to present a methodology and rationale for development of a Nonintrusive Inflight Data Collection System (NIDCS) to collect Human Factors (HF) data during a space mission. These data will enable the research team to identify and resolve issues. This paper will present the background and history of the NIDCS, the methodology and techniques employed versus those in current use on Earth, initial results of the effort--including a brief description of the equipment, and, finally, a discussion of the scientific importance and possible future applications of this system elsewhere. The schema for the NIDCS includes a collection of three types of data: behavioral, physiological, and biomechanical. These will be collected using videotape of crew members' activities, bioelectric signal measurement, and measurement of kinematics and kinetics, respectively. This paper will focus on the second type of data, physiological activity as determined by changes in bioelectric potentials as crew members perform daily assignments.

Micocci, Angelo↗
NASA NTRS1995

Microelectronics in Japan

The purpose of this JTEC study is to evaluate Japan's electronic manufacturing and packaging capabilities within the context of global economic competition. To carry out this study, the JTEC panel evaluated the framework of the Japanese consumer electronics industry and various technological and organizational factors that are likely to determine who will win and lose in the marketplace. This study begins with a brief overview of the electronics industry, especially as it operates in Japan today. Succeeding chapters examine the electronics infrastructure in Japan and take an in-depth look at the central issues of product development in order to identify those parameters that will determine future directions for electronic packaging technologies.

Boulton, William R.↗
NASA NTRS1994

Discharge lamp technologies

This talk is an overview of discharge lamp technology commonly employed in general lighting, with emphasis on issues pertinent to lighting for plant growth. Since the audience is primarily from the plant growth community, and this begins the light source part of the program, we will start with a brief description of the discharge lamps. Challenges of economics and of thermal management make lamp efficiency a prime concern in controlled environment agriculture, so we will emphasize science considerations relating to discharge lamp efficiency. We will then look at the spectra and ratings of some representative lighting products, and conclude with a discussion of technological advances.

Dakin, James↗
NASA NTRS2001

The Air Transportation Policy of Small States: Meeting the Challenges of Globalization

The air transport policies of small states are currently at a crossroad. Policy makers in these countries are facing a difficult dilemma: either follow the general trend of liberalization and pay the high cost of the resulting restructuring or maintain the existing regulatory and ownership structures at the risk of isolation thus undermining the viability and sustainability of their air transport sector and their economies in general. This paper proposes to explore the broad issues raised by this difficult dilemma, to outline its special significance in the context of small states and to delineate the options opened to the economic policymakers; in these states. After a brief note on the method of research, we sketch the main elements of the international air transport industry in which the airlines of small states are called upon to act. We then propose to review the main features of the analytical framework of this debate as it pertains to the special circumstances of these states. Then we focus on the challenges facing the airlines of Small States, while the next section proposes a number of the alternative policy options open to the policy makers in these states. The main conclusions are drawn in the final section.

Antoniou, Andreas↗
NASA NTRS2002

Space flight nutrition research: platforms and analogs

Conducting research during actual or simulated weightlessness is a challenging endeavor, where even the simplest activities may present significant challenges. This article reviews some of the potential obstacles associated with performing research during space flight and offers brief descriptions of current and previous space research platforms and ground-based analogs, including those for human, animal, and cell-based research. This review is intended to highlight the main issues of space flight research analogs and leave the specifics for each physiologic system for the other papers in this section.

NASA Discipline Regulatory Physiology↗