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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 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Digital avionics design and reliability analyzer

The description and specifications for a digital avionics design and reliability analyzer are given. Its basic function is to provide for the simulation and emulation of the various fault-tolerant digital avionic computer designs that are developed. It has been established that hardware emulation at the gate-level will be utilized. The primary benefit of emulation to reliability analysis is the fact that it provides the capability to model a system at a very detailed level. Emulation allows the direct insertion of faults into the system, rather than waiting for actual hardware failures to occur. This allows for controlled and accelerated testing of system reaction to hardware failures. There is a trade study which leads to the decision to specify a two-machine system, including an emulation computer connected to a general-purpose computer. There is also an evaluation of potential computers to serve as the emulation computer.

Source record↗
NASA NTRS1982

Space Experiments with Particle Accelerators (SEPAC)

Plans for SEPAC, an instrument array to be used on Spacelab 1 to study vehicle charging and neutralization, beam-plasma interaction in space, beam-atmospheric interaction exciting artificial aurora and airglow, and the electromagnetic-field configuration of the magnetosphere, are presented. The hardware, consisting of electron beam accelerator, magnetoplasma arcjet, neutral-gas plume generator, power supply, diagnostic package (photometer, plasma probes, particle analyzers, and plasma-wave package), TV monitor, and control and data-management unit, is described. The individual SEPAC experiments, the typical operational sequence, and the general outline of the SEPAC follow-on mission are discussed. Some of the experiments are to be joint ventures with AEPI (INS 003) and will be monitored by low-light-level TV.

Obayashi, T.↗
NASA NTRS1978

Platform motion for fighter simulations

The reported investigation is concerned with aspects of 'realistic' cue generation and evaluation. 'Realistic' cues are defined to mean cues that are representative of an aircraft, that are of sufficient magnitude to be sensed, that are in the proper direction arriving at the proper time, and yet that are within the presentation capabilities of the washout/synergistic platform system. Attention is given to the aircraft mathematical model, computer implementation, cockpit hardware, visual display, the motion system, vertical acceleration, longitudinal acceleration and pitch rate, and lateral acceleration and roll rate. The motion cues for fighter aircraft produced by Langley nonlinear adaptive washout/synergistic motion base system are found to be unacceptable in the roll axis representation. However, a method for producing potentially realistic roll cues is identified.

Parrish, R. V.↗
NASA NTRS1972

Silicon-germanium technology program of the Jet Propulsion Laboratory.

The outer planetary exploration missions studied by the Jet Propulsion Laboratory require silicon-germanium radioisotope thermoelectric generators (RTGs) in which the factors of safety are as low as is compatible with the reliable satisfaction of the power needs. Work on silicon germanium sublimation performed at the Jet Propulsion Laboratory is presented. Analytical modeling work on the solid-diffusion process involved in the steady-state (free) sublimation of silicon germanium is described. Analytical predictions are made of the sublimation suppression which can be achieved by using a cover gas. A series of accelerated (high-temperature) tests which were performed on simulated hardware (using four SiGe couples) to study long-term sublimation and reaction mechanisms are also discussed.

De Winter, F.↗
NASA NTRS1965

Dry film lubricants

The Space Age has necessitated accelerated development of many technologies which have direct application to commercial, earthbound hardware. One striking example is dry film lubrication. The stimulus for the development of dry film lubricants was provided by the unsatisfactory condition created when commercial liquid lubricants were exposed to the multiple environs of space. In the search for a satisfactory solution to lubrication in space, dry films were investigated. The dry film lubrication concept has proven most desirable for space, and a natural fallout is the potential shown by such films for consumer item application. On the acceptance that the coefficient of friction of dry films is not equivalent to that of a liquid lubricant under ideal conditions, this paper discusses how the ideal condition for liquid lubrication is rarely achieved in practical applications. Comparisons are made between the performance of dry film and liquid lubricants as a function of temperature, environmental pressure, and life. Furthermore, consideration is given to the comparative costs of liquid versus dry film lubricants to show the practicality and desirability of dry film lubrication to consumer items. Although no data on the performance of consumer items lubricated with dry films are presented, the comparisons clearly establish the potential of dry film lubricants in a competitive consumer market.

SOLID LUBRICANT↗
NASA NTRS1994

Review of European Microgravity Measurements

AA In a French/Russion cooperation, CNES developed a microgravity detection system for analyzing the Mir space station micro-g-environment for the first time. European efforts to characterize the microgravity (1/9) environment within a space laboratory began in the late seventies with the design of the First Spacelab Mission SL-1. Its Material Science Double Rack was the first payload element to carry its own tri-axial acceleration package. Even though incapable for any frequency analysis, the data provided a wealth of novel information for optimal experiment and hardware design and operations for missions to come. Theoretical investigations under ESA contract demonstrated the significance of the detailed knowledge of micro-g data for a thorough experiment analysis. They especially revealed the high sensitivity of numerous phenomena to low frequency acceleration. Accordingly, the payloads of the Spacelab missions D-1 and D-2 were furnished with state-of-the-art detection systems to ensure frequency analysis between 0.1 and 100 Hz. The Microgravity Measurement Assembly (MMA) of D-2 was a centralized system comprising fixed installed as well as mobile tri-axial packages showing real-time data processing and transmission to ground. ESA's free flyer EURECA carried a system for continuous measurement over the entire mission. All EURECA subsystems and experimental facilities had to meet tough requirements defining the upper acceleration limits. In a French/Russion cooperation, CNES developed a mi crogravity detection system for analyzing the Mir space station micro-g-environment for the first time. An approach to get access to low frequency acceleration between 0 and 0.02 Hz will be realized by QSAM (Quasi-steady Acceleration Measurement) on IML-2, complementary to the NASA system Spacelab Acceleration Measurement System SAMS. A second flight of QSAM is planned for the Russian free flyer FOTON.

H Hamacher↗
NASA NTRS1968

Power Matching of an Ion Thruster to Solar Cell Power Output

A 20-cm-diam thruster was operated over a 2:1 range of output power, allowing for continuous matching of thruster power to a varying solar cell output level. The technique of matching power by varying either the ion beam current or the net accelerating voltage is described. Ion beam current control, implemented in thruster control loops, utilized existing laboratory hardware. Stable thruster operation was achieved over a range of 1000 to 2000 W. Bistable values of mercury propellant flow at the same discharge chamber and ion beam conditions were also observed.

Pawlik, Eugene V.↗
NASA NTRS1975

Feasibility of miniaturized instrumentation of the inflatable sphere for temperature, pressure and acceleration measurement

The feasibility of instrumenting the inflatable passive sphere (presently used to provide upper atmosphere density measurements) with miniaturized thermistors, pressure transducers, and accelerometers was analyzed. Data from the sensors must be transmitted by an onboard telemetry system to a ground receiving station. To assure a sufficiently slow fall velocity for the sphere the additional mass of the sensor and telemetry hardware must be less than 100 grams. Other constraints that must be satisfied by the sensor and telemetry systems include the ability to withstand a 150 g launch acceleration, the ability to function in both high and low temperature and pressure environments and be sufficiently small to be packaged within the body of a 3.81 cm diameter dart. A differential transducer that will measure the difference between ambient and internal sphere pressures is recommended. The application of each type of measurement relative to its ability to monitor sphere malfunction and to provide additional meteorological data is considered.

Luers, J. K.↗
NASA NTRS1982

Preliminary design of flight hardware for two-phase fluid research

This study defined the preliminary designs of flight software for the Space Shuttle Orbiter for three two-phase fluid research experiments: (1) liquid reorientation - to study the motion of liquid in tanks subjected to small accelerations; (2) pool boiling - to study low-gravity boiling from horizontal cylinders; and (3) flow boiling - to study low-gravity forced flow boiling heat transfer and flow phenomena in a heated horizontal tube. The study consisted of eight major tasks: reassessment of the existing experiment designs, assessment of the Spacelab facility approach, assessment of the individual carry-on approach, selection of the preferred approach, preliminary design of flight hardware, safety analysis, preparation of a development plan, estimates of detailed design, fabrication and ground testing costs. The most cost effective design approach for the experiments is individual carry-ons in the Orbiter middeck. The experiments were designed to fit into one or two middeck lockers. Development schedules for the detailed design, fabrication and ground testing ranged from 15 1/2 to 18 months. Minimum costs (in 1981 dollars) ranged from $463K for the liquid reorientation experiment to $998K for the pool boiling experiment.

Hustvedt, D. C.↗
NASA NTRS1979

Point Focusing Thermal and Electric Applications Project. Volume 2: Workshop proceedings

Point focus distributed receiver solar thermal technology for the production of electric power and of industrial process heat is discussed. Thermal power systems are described. Emphasis is on the development of cost effective systems which will accelerate the commercialization and industrialization of plants, using parabolic dish collectors. The characteristics of PFDR systems and the cost targets for major subsystems hardware are identified. Markets for this technology and their size are identified, and expected levelized bus bar energy costs as a function of yearly production level are presented. The present status of the technology development effort is discussed.

Landis, K. E.↗
NASA NTRS1975

Impact accelerations

The degree to which impact acceleration is an important factor in space flight environments depends primarily upon the technology of capsule landing deceleration and the weight permissible for the associated hardware: parachutes or deceleration rockets, inflatable air bags, or other impact attenuation systems. The problem most specific to space medicine is the potential change of impact tolerance due to reduced bone mass and muscle strength caused by prolonged weightlessness and physical inactivity. Impact hazards, tolerance limits, and human impact tolerance related to space missions are described.

Henning E. von Gierke↗
NASA NTRS1972

Rotor blade boundary layer measurement hardware feasibility demonstration

A traverse mechanism which allows the measurement of the three dimensional boundary layers on a helicopter rotor blade has been built and tested on a full scale rotor to full scale conditions producing centrifugal accelerations in excess of 400 g and Mach numbers of 0.6 and above. Boundary layer velocity profiles have been measured over a range of rotor speeds and blade collective pitch angles. A pressure scanning switch and transducer were also tested on the full scale rotor and found to be insensitive to centrifugal effects within the normal main rotor operating range. The demonstration of the capability to measure boundary layer behavior on helicopter rotor blades represents the first step toward obtaining, in the rotating system, data of a quality comparable to that already existing for flows in the fixed system.

Clark, D. R.↗
NASA NTRS1974

Evaluation report for toggle switches: Micro Switch and Cutler-Hammer models per MIL-S-3950

Several models of hermetically sealed toggle switches meeting the requirements of MIL-S-3950, were evaluated to determine the probability that they would withstand the environmental requirements of, and therefore be suitable for use on, the space shuttle vehicle. The evaluation was started with a comparison of the environmental requirements for space shuttle hardware. This was followed with in-house testing for those environments where a reasonably firm conclusion could not be drawn in the comparison. Space simulation, acceleration, and vibration testing were performed in-house.

Labberton, D.↗
NASA NTRS1997

NASA Aerospace Flight Battery Systems Program Update

The objectives of NASA's Aerospace Flight Battery Systems Program is to: develop, maintain and provide tools for the validation and assessment of aerospace battery technologies; accelerate the readiness of technology advances and provide infusion paths for emerging technologies; provide NASA projects with the required database and validation guidelines for technology selection of hardware and processes relating to aerospace batteries; disseminate validation and assessment tools, quality assurance, reliability, and availability information to the NASA and aerospace battery communities; and ensure that safe, reliable batteries are available for NASA's future missions.

Manzo, Michelle↗
NASA NTRS1979

Heat and electricity from the sun using parabolic dish collector systems

The paper investigates point focus distributed receiver (PFDR) solar thermal technology for the production of electric power and of industrial process heat. Attention is given to a thermal systems project conducted by JPL under DOE sponsorship. It is reported that project emphasis is on the development of cost-effective systems which will accelerate the commercialization and industrialization of plants up to 10 MWe, using parabolic dish collectors. Also discussed are the characteristics of PFDR systems, the cost targets for major systems hardware, and markets for this technology. Finally, the present system status of the technology development effort is discussed.

Truscello, V. C.↗
NASA NTRS1980

A Recoverable Plasma Diagnostics Package (RPDP) for Spacelab

The RPDP is a fully instrumented, ejectable and recoverable unit with flight and ground support systems so that it can be utilized attached to the orbiter remote manipulator system, tethered from the orbiter, or as an orbiter subsatellite. Core instruments on the RPDP are flight proven hardware which provide diagnostics measurements of energetic particles, AC electromagnetic and electrostatic waves, vector magnetic field signatures of current systems, vector electric field signatures associated with plasma flow and particle acceleration, thermal plasma ion composition and density, thermal plasma electron density and temperature, and images of optical emissions regions in UV or visible wavelengths.

Shawhan, S. D.↗
NASA NTRS2026

NASA JSC’s Simulant Development Lab Capabilities and Artemis Testing

The Simulant Development Lab (SDL) is a multifunctional collaborative workspace that supports the development, curation, analysis, testing, and distribution of planetary regolith simulants – including lunar, Martian, asteroidal, and other granular materials. The lab provides a multidisciplinary setting for scientific characterization of simulant physical properties and for engineering evaluations conducted with simulant test beds. To enable this work, the SDL curates and maintains a stock of more than 35 metric tons of simulant material. To evaluate these materials and support testing goals, the lab is equipped with a comprehensive suite of processing tools and analytical instruments. These capabilities enable the SDL’s mission at NASA’s Johnson Space Center to distribute, develop, process, characterize, and test regolith simulants for mission relevant applications. Through controlled and repeatable testing environments that replicate the physical and compositional properties of lunar regolith, the SDL supports Artemis hardware maturation, providing safe, Earth‑based analogs for evaluating systems that must withstand regolith dust interactions, physical wear and abrasion, and operational loads. The facility’s extensive simulant inventory and integrated geological and engineering test infrastructure accelerate technology readiness for Artemis and future exploration campaigns (e.g., future crewed or robotic missions to Mars).

Simulant Development Lab↗
NASA NTRS1972

Long life assurance study for manned spacecraft long life hardware. Volume 5: Long life assurance test and study recommendations

A study was conducted to establish the guidelines to be applied to the selection of equipment for manned spacecraft systems. Recommendations for expansion of the original study are submitted. The subjects considered are: (1) designing to severe dynamic requirements; (2) analysis of in-space failures due to life limitations; (3) accelerated testing of semiconductors; (4) fan life verification; (5) testing of solid tantalum capacitors; (6) testing of teflon valve seats; and (7) electromigration model verification.

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