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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 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

The Geology of Mt. Hope, a Silicic Volcanic Center in West Central Arizona

The purpose was to establish a detailed history of the sequence of geologic events which occurred at Mt. Hope and an area 6.8 miles in diameter surrounding it. The final result will be comprised of information collected during field mapping, with data from petrographic studies and wet chemical analyses. From this it should be possible to suggest relationships to other volcanic regions, particularly bimodal suites in the transition zone, and gain a clearer picture of the petrologic nature of this area. Field work conducted this past summer confirmed the bimodal nature of volcanism at Mt. Hope. The symmetrical, radial cone is comprised of several rhyolites with numerous intrusions of intermediate-composition dikes and two breccia pipes near the summit.

Simmons, A. M.↗
NASA NTRS1987

Effect of object potentials on the wake of a flowing plasma

The structure of the electric potential and ion density of the ion front in the near wake created by the flow of synthetic plasma past a conducting plate was investigated experimentally and numerically, with particular attention given to the effect of plate potential on the structure of the ion front. Results were obtained for a molecular nitrogen plasma with ambient electron densities of about 100,000/cu cm, ion temperatures of about 0.025 eV, electron temperatures of about 0.3 eV, and plasma flow velocities of about 10,000 m/s. Two-dimensional simulations of the laboratory experiments were performed by using a multiple waterbag technique. The calculated and experimental results show that wake closure is well described by the acceleration of ions in the plasma steady-state electric field. However, the ion-front motion is strongly affected by the imposed potential of the object creating the wake.

Katz, I.↗
NASA NTRS1989

Deep levels and radiation effects in p-InP

A survey was conducted on past studies of hole traps in InP. An experiment was designed to evaluate hole traps in Zn-doped InP after fabrication, after electron irradiation and after annealing using deep level transient spectroscopy. Data similar to that of Yamaguchi was seen with observation of both radiation-induced hole and electron traps at E sub A=0.45 eV and 0.03 eV, respectively. Both traps are altered by annealing. It is also shown that trap parameters for surface-barrier devices are influenced by many factors such as bias voltage, which probes traps at different depths below the surface. These devices require great care in data evaluation.

Anderson, W. A.↗
NASA NTRS1993

Toward lowering the cost of mission operations

The mission operations system is one of the more significant drivers of the cost of the mission operations and data analysis segment of missions. In large or long-lived projects, the MOS can also be a driver in total mission cost. Larger numbers of missions, together with an increasingly cost-conscious environment, dictate that future missions must more strictly control costs as they perform to their requirements. It is therefore prudent to examine the conduct of past missions for ways to conserve resources. In this paper we review inputs made to past projects' 'lessons-learned' activities, in which personnel from past projects (among other things) identified major cost drivers of MOS's and considered how economies were or might have been realized in both design and performance of their MOS. Common themes among four such reviews are summarized in an attempt to provide suggestions for cost reduction in future missions.

Wall, S. D.↗
NASA NTRS2011

NASA's Human Rating Requirements - A Historical Interpretive Perspective

Section 3.0 of NASA's Human Rating Requirements for Space Systems, NPR 8705.2, represents technical engineering requirements that the Agenc y requires of Human Space Systems. In many cases the requirements are not unlike requirements for any space system, crewed or uncrewed, th ey deal with successfully accomplishing the mission objectives. Howev er, they go one step further and have requirements that go beyond suc cessful completion of the mission and dictate functions or actions ne cessary to assure the survival of the crew. In that regard they are u nique from other space system requirements. Even with their uniquenes s the technical requirements of the NPR 8705.2 have been relatively u nchanged in overall intent over the revisions. They all have provided for system redundancy, crew habitable environment, crew situational awareness, crew operation, system control, emergency egress and abort systems. In a few cases the intent of the requirement was changed in tentionally, either to restrict certain types of systems or their fun ctions, or to encompass lessons learned from previous programs. For t he most part the requirements are non controversial and represent the current best practices for human space systems, however, a few requi rements are always debated and have evolved over revisions of the NPR due to studies conducted with various programs like the Orbital Spac e Plane and the Constellation Programs. Those requirements will be di scussed using results of trade studies conducted during past programs highlighting how these particular requirements have evolved through the revisions of the NPR. Comments will also be provided for requirem ents that although not debated, have provided challenges in interpret ation.

Langford, Gerald↗
NASA NTRSDate not supplied

Thermal Desktop Modeling of 2016 CRYOTE-2 Tank Chill and Fill Testing

The storing and transfer of cryogenic propellants is an enabling technology for NASA and industry as civilization moves to expand future missions into low Earth orbit and beyond. Several ground propellant transfer tests have been conducted in past decades examining various tank chilldown and fill methods. Creating accurate models using these historical datasets is a vital step toward developing appropriate modeling tools to form pre-test predictions for subsequent ground and flight propellant transfers. This paper presents model validation of Thermal Desktop using data from the 2016 CRYOTE-2 liquid nitrogen transfer experiments whose purpose was to demonstrate the chill and fill process in a spherical receiver tank. Tank pressure, fill level, and wall temperature were all modeled and compared with 8 test cases using two modeling methods, Mass Controlled, and Pressure Controlled. This test series is the hardest Thermal Desktop tank chill and fill validation case to-date, yet the model was able to accurately predict each of these metrics for the 2016 tests within 28%, 10%, 20% respectively, for pressure, fill level, and wall temperature using the Mass Controlled model, and 29%, 79%, and 12%, respectively for the Pressure Controlled model.

Cryogenic Tank Chilldown↗
NASA NTRS1988

Fifty years of laminar flow flight testing

Laminar flow flight experiments conducted over the past 50 years are reviewed. The emphasis is on flight testing conducted under the NASA Laminar Flow Control Program, which has been directed towards the most challenging technology application, the high-subsonic-speed transport. The F111/TACT NLF Glove Flight Test, the F-14 Variable-Sweep Transition Flight Experiment, the 757 Wing-Noise Survey and NLF Glove Flight Test, the NASA Jetstar Leading-Edge Flight Test Program, and the recently initiated Hybrid Laminar-Flow-Control Flight Experiment are discussed.

Wagner, R. D.↗
NASA NTRS2004

Office of Equal Opportunity Programs

The NASA Glenn Office of Equal Opportunity Programs works to provide quality service for all programs and/or to assist the Center in becoming a model workplace. During the summer of 2004, I worked with Deborah Cotleur along with other staff members to create and modify customer satisfaction surveys. This office aims to assist in developing a model workplace by providing functions as a change agent to the center by serving as an advisor to management to ensure equity throughout the Center. In addition, the office serves as a mediator for the Center in addressing issues and concerns. Lastly, the office provides assistance to employees to enable attainment of personal and organizational goals. The Office of Equal Opportunities is a staff office which reports and provides advice to the Center Director and Executive Leadership, implements laws, regulations, and presidential executive orders, and provides center wide leadership and assistance to NASA GRC employees. Some of the major responsibilities of the office include working with the discrimination complaints program, special emphasis programs (advisory groups), management support, monitoring and evaluation, contract compliance, and community outreach. During my internship in this office, my main objective was to create four customer satisfaction surveys based on EO retreats, EO observances, EO advisory boards, and EO mediation/counseling. I created these surveys after conducting research on past events and surveys as well as similar survey research created and conducted by other NASA centers, program for EO Advisory group members, leadership training sessions for supervisors, preventing sexual harassment training sessions, and observance events. I also conducted research on the style and format from feedback surveys from the Marshall Equal Opportunity website, the Goddard website, and the main NASA website. Using the material from the Office of Equal Opportunity Programs at Glenn Research Center along with my previous research, I created four customer satisfaction surveys. Additional information is included in the original extended abstract.

Chin, Jennifer L.↗
NASA NTRS1990

Current collection by a long conducting cylinder in a flowing magnetized plasma

The numerical techniques, the definitions, and the normalizations used in the simulations of plasma flow past a long conducting cylinder with a magnetic field along the cylinder axis are described. The effect of cross-field plasma transport on the current collection without any contribution to the current from the field-aligned motion of the plasma particles is highlighted. The electric fields in the structure create a two-cell circulation of the electrons near the cylinder. The cell in the wake region has negative potentials. A fan-shaped circulation cell forms around the cylinder and in this cell the potential is generally positive. The geometry and the size of this positive cell affect the current collection. The potential structure around the cylinder is examined, along with its effect on the current collection and its oscillatory behavior. The variation of the time-average current as a function of the relative motion between the plasma and the cylinder is also investigated.

Singh, Nagendra↗
NASA NTRS2017

Development of Augmented Spark Impinging Igniter System for Methane Engines

The Lunar Cargo Transportation and Landing by Soft Touchdown (Lunar CATALYST) program is establishing multiple no-funds-exchanged Space Act Agreement (SAA) partnerships with U.S. private sector entities. The purpose of this program is to encourage the development of robotic lunar landers that can be integrated with U.S. commercial launch capabilities to deliver payloads to the lunar surface. As part of the efforts in Lander Technologies, NASA Marshall Space Flight Center (MSFC) is developing liquid oxygen (LOX) and liquid methane (LCH4) engine technology to share with the Lunar CATALYST partners. Liquid oxygen and liquid methane propellants are attractive owing to their relatively high specific impulse for chemical propulsion systems, modest storage requirements, and adaptability to NASA's Journey to Mars plans. Methane has also been viewed as a possible propellant choice for lunar missions, owing to the performance benefits and as a technology development stepping stone to Martian missions. However, in the development of methane propulsion, methane ignition has historically been viewed as a high risk area in the development of such an engine. A great deal of work has been conducted in the past decade devoted to risk reduction in LOX/CH4 ignition. This paper will review and summarize the history and results of LOX/CH4 ignition programs conducted at NASA. More recently, a NASA-developed Augmented Spark Impinging (ASI) igniter body, which utilizes a conventional spark exciter system, is being tested with LOX/CH4 to help support internal and commercial engine development programs, such as those in Lunar CATALYST. One challenge with spark exciter systems, especially at altitude conditions, is the ignition lead that transmits the high voltage pulse from the exciter to the spark igniter (spark plug). The ignition lead can be prone to corona discharge, reducing the energy delivered by the spark and potentially causing non-ignition events. For the current work, a commercial compact exciter system, which eliminates this high voltage cabling, was tested at altitude conditions. A modified, conventional exciter system with an improved ignition lead was also recently tested at altitude conditions. This test program demonstrated the capability of these exciter systems to operate at altitude. While more extensive testing may be required, these systems or similar ones may be used for future NASA and commercial engine programs.

methane↗
NASA NTRS1990

Comparative psychology and the great apes - Their competence in learning, language, and numbers

An overview of comparative studies conducted for the past three decades is presented. These studies have led to the establishment of the Language Research Center that provides facilities for research into questions of primate behavior and cognition. Several experiments conducted among chimpanzees are discussed and comparative analyses with the lesser apes, monkeys, and humans are offered. Among the primates, brain complexity varies widely and the evidence is strong that encephalization and enhanced brain complexity facilitate the learning of concepts, the transfer of learning to an advantage, and mediational and observational learning.

Rumbaugh, Duane M.↗
NASA NTRS1973

Transonic flow past lifting wings.

Work conducted by Norstrud (1971) has been extended to lifting flows with the inclusion of embedded continuous supercritical regions. The approach taken follows some fundamental steps proposed for two-dimensional flows by Oswatitsch (1950). The governing integral equation is replaced by a system of nonlinear algebraic equations. The method of parametric differentiation is applied to the solution of this system of equations. The analytical analysis is discussed together with a numerical analysis in the case of a wing configuration with arbitrary thickness distribution.

Norstrud, H.↗
NASA NTRSDate not supplied

An Overview of Plume-Surface Interaction Testing and Research

NASA has studied rocket plume-surface interactions caused by spacecraft since the Apollo era to reduce risk to landing vehicles. The study of plume-surface interactions is a multi-discipline effort, spanning aerospace engineering to planetary science. Historical testing for Apollo and Viking produced methods, terms, and datasets that influence the field today. Research conducted over the past two decades has expanded our understanding of plume-surface interaction phenomena, but the problem remains resistant to a robust predictive capability. Contemporary experimental and modeling efforts to understand and retire strategic knowledge gaps will be discussed, with a focus on work conducted under NASA’s Plume-Surface Interaction Project and the upcoming Human Landing System Plume-Surface Interaction Risk Reduction Ground Test.

Wesley A Chambers↗
NASA NTRS2010

2010 NASA Range Safety Annual Report

this report provides a NASA Range Safety overview for current and potential range users. This report contains articles which cover a variety of subject areas, summaries of various NASA Range Safety Program activities conducted during the past year, links to past reports, and information on several projects that may have a profound impact on the way business will be done in the future. Specific topics discussed in the 2010 NASA Range Safety Annual Report include a program overview and 2010 highlights; Range Safety Training; Range Safety Policy revision; Independent Assessments; Support to Program Operations at all ranges conducting NASA launch/flight operations; a continuing overview of emerging range safety-related technologies; and status reports from all of the NASA Centers that have Range Safety responsibilities. Every effort has been made to include the most current information available. We recommend this report be used only for guidance and that the validity and accuracy of all articles be verified for updates. Once again, the web-based format was used to present the annual report.

Dumont, Alan G.↗
NASA NTRS1994

Composite chronicles: A study of the lessons learned in the development, production, and service of composite structures

A study of past composite aircraft structures programs was conducted to determine the lessons learned during the programs. The study focused on finding major underlying principles and practices that experience showed have significant effects on the development process and should be recognized and understood by those responsible for using of composites. Published information on programs was reviewed and interviews were conducted with personnel associated with current and past major development programs. In all, interviews were conducted with about 56 people representing 32 organizations. Most of the people interviewed have been involved in the engineering and manufacturing development of composites for the past 20 to 25 years. Although composites technology has made great advances over the past 30 years, the effective application of composites to aircraft is still a complex problem that requires experienced personnel with special knowledge. All disciplines involved in the development process must work together in real time to minimize risk and assure total product quality and performance at acceptable costs. The most successful programs have made effective use of integrated, collocated, concurrent engineering teams, and most often used well-planned, systematic development efforts wherein the design and manufacturing processes are validated in a step-by-step or 'building block' approach. Such approaches reduce program risk and are cost effective.

Vosteen, Louis F.↗
NASA NTRS2012

2011 NASA Range Safety Annual Report

Welcome to the 2011 edition of the NASA Range Safety Annual Report. Funded by NASA Headquarters, this report provides a NASA Range Safety overview for current and potential range users. As is typical with odd year editions, this is an abbreviated Range Safety Annual Report providing updates and links to full articles from the previous year's report. It also provides more complete articles covering new subject areas, summaries of various NASA Range Safety Program activities conducted during the past year, and information on several projects that may have a profound impact on the way business will be done in the future. Specific topics discussed and updated in the 2011 NASA Range Safety Annual Report include a program overview and 2011 highlights; Range Safety Training; Range Safety Policy revision; Independent Assessments; Support to Program Operations at all ranges conducting NASA launch/flight operations; a continuing overview of emerging range safety-related technologies; and status reports from all of the NASA Centers that have Range Safety responsibilities. Every effort has been made to include the most current information available. We recommend this report be used only for guidance and that the validity and accuracy of all articles be verified for updates. Once again the web-based format was used to present the annual report. We continually receive positive feedback on the web-based edition and hope you enjoy this year's product as well. As is the case each year, contributors to this report are too numerous to mention, but we thank individuals from the NASA Centers, the Department of Defense, and civilian organizations for their contributions. In conclusion, it has been a busy and productive year. I'd like to extend a personal Thank You to everyone who contributed to make this year a successful one, and I look forward to working with all of you in the upcoming year.

Dumont, Alan G.↗
NASA NTRS1981

Development of an all-metal thick-film cost-effective metallization system for solar cells

Screened electrodes made from fluorocarbon activated copper paste and silver fluoride activated copper paste, tape adhesion and scratch tests were studied. Experiments were conducted with variations in past parameters, firing conditions, including gas ambients, furnace furniture, silicon surface and others. A liquid medium intended to provide transport during the carbon fluoride decomposition, is incorporated in the paste.

Ross, B.↗
NASA NTRS1993

Turbulence and transition modeling for high-speed flows

Research conducted during the past three and a half years aimed at developing and testing a turbulence/transition model applicable to high-speed turbulent flows is summarized. The first two years of the project focused on fully turbulent flows, while emphasis shifted to boundary-layer development in the transition region during the final year and a half. A brief summary of research accomplished during the first three years is included and publications that describe research results in greater detail are cited. Research conducted during the final six months of the period of performance is summarized. The primary results of the last six months of the project are elimination of the k-omega model's sensitivity to the freestream value of omega and development of a method for triggering transition at a specified location, independent of the freestream turbulence level.

Wilcox, David C.↗