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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 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
NASA NTRS2011

Multiplexed Energy Coupler for Rotating Equipment

A multiplexing antenna assembly can efficiently couple AC signal/energy into, or out of, rotating equipment. The unit only passes AC energy while blocking DC energy. Concentric tubes that are sliced into multiple pieces are assembled together so that, when a piece from an outer tube aligns well with an inner tube piece, efficient energy coupling is achieved through a capacitive scheme. With N outer pieces and M inner pieces, an effective N x M combination can be achieved in a multiplexed manner. The energy coupler is non-contact, which is useful if isolation from rotating and stationary parts is required. Additionally, the innovation can operate in high temperatures. Applications include rotating structure sensing, non-contact energy transmission, etc.

Zhao, Xiaoliang↗
NASA NTRS1995

Comparison of HALOE O3 and H2O observations from UARS with ground and balloonborne measurements

The HALogen Occultation Experiment (HALOE) was launched on the Upper Atmosphere Research Satellite (UARS) by the Space Shuttle Discovery at 7:11:04 EDT on September 12, 1991. After allowing for a period of outgassing, HALOE began taking routine science observations on October 11. HALOE uses the experiment approach of solar occultation and the gas filter and broad band radiometer instruments techniques to measure vertical profiles of HCl, HF, CH4, NO, NO2, H2O, O3, aerosol, and temperature versus pressure. The measurements cover a broad altitude range from the upper troposphere in some cases to the lower thermosphere in the case of nitric oxide. Latitude coverage provided by the occultation geometry ranges from 80 deg S to 80 deg N over the course of one year. The experiment has operated essentially without flaw for more than three years. Instrument stability over this time, as judged by the maximum signal change when viewing the sun exoatmospherically is less than or equal to 2 to 3%.

Russell, James M., III↗
NASA NTRS1969

Apollo 11 - Crew observations

Apollo 11 mission crew observation of operational and scientific phenomena associated with lunar landings, discussing preflight geologic training and briefings

Aldrin, E. E.↗
NASA NTRS1987

Active vehicle charging measurements in sounding rocket and space shuttle orbiter environments at Low Earth Orbit (LEO) altitude

It was concluded that for electron beam emission up to 100mA, vehicle charging is not a significant problem with the Space Shuttle Orbiter. Similarly, sounding rocket payloads have no serious charging problems up to this level of beam current, provided that the maximum amount of the rocket skin is available to collect ionospheric electrons from the LEO altitude range. However, sounding rockets are marginal in their collecting area capability and other effects may occur to balance the beam current when operated at lower altitudes during the night.

Raitt, W. J.↗
NASA NTRS1986

Materials compatibility issues related to thermal energy storage for a space solar dynamic power system

Attention is given to results obtained to date in developmental investigations of a thermal energy storage (TES) system for the projected NASA Space Station's solar dynamic power system; these tests have concentrated on issues related to materials compatibility for phase change materials (PCMs) and their containment vessels' materials. The five PCMs tested have melting temperatures that correspond to the operating temperatures of either the Brayton or Rankine heat engines, which were independently chosen for their high energy densities.

Faget, N. M.↗
NASA NTRS1992

The AXAF CCD imaging spectrometer

The current status of the instrument design and the status of the CCDs being fabricated for the AXAF CCD Imaging Spectrometer (ACIS) are summarized. The instrument consists of an image recording array of CCDs and a linear arrangement of CCDs to record the spectra formed by the objective grating spectrometer. Both arrays employ CCDs with pixel dimensions which correspond to about 0.5 arcsec samples of the image. The CCDs provide moderate spectral resolution and good detection efficiency over the energy range 0.5 to 10 keV. Spectral resolution of 200 or more is achievable using the objective grating with the grating array. Radiation damage effects are shown to degrade the energy resolution of CCDs. Specially designed CCD pixel architecture is employed together with shielding and low temperature operation to slow the effects of radiation damage.

Garmire, G. P.↗
NASA NTRS2008

Mars Phoenix Entry, Descent, and Landing Simulation Design and Modelling Analysis

The 2007 Mars Phoenix Lander was launched in August of 2007 on a ten month cruise to reach the northern plains of Mars in May 2008. Its mission continues NASA s pursuit to find evidence of water on Mars. Phoenix carries upon it a slew of science instruments to study soil and ice samples from the northern region of the planet, an area previously undiscovered by robotic landers. In order for these science instruments to be useful, it was necessary for Phoenix to perform a safe entry, descent, and landing (EDL) onto the surface of Mars. The EDL design was defined through simulation and analysis of the various phases of the descent. An overview of the simulation and various models developed to characterize the EDL performance is provided. Monte Carlo statistical analysis was performed to assess the performance and robustness of the Phoenix EDL system and are presented in this paper. Using these simulation and modelling tools throughout the design and into the operations phase, the Mars Phoenix EDL was a success on May 25, 2008.

Prince, Jill L.↗
NASA NTRS2016

Autonomous Operations System: Development and Application

Autonomous control systems provides the ability of self-governance beyond the conventional control system. As the complexity of mechanical and electrical systems increases, there develops a natural drive for developing robust control systems to manage complicated operations. By closing the bridge between conventional automated systems to knowledge based self-awareness systems, nominal control of operations can evolve into relying on safe critical mitigation processes to support any off-nominal behavior. Current research and development efforts lead by the Autonomous Propellant Loading (APL) group at NASA Kennedy Space Center aims to improve cryogenic propellant transfer operations by developing an automated control and health monitoring system. As an integrated systems, the center aims to produce an Autonomous Operations System (AOS) capable of integrating health management operations with automated control to produce a fully autonomous system.

Autonomous Control Systems↗
NASA NTRS2017

Lightning Imaging Sensor (LIS) on the International Space Station (ISS): Launch, Installation, Activation and First Results

Mission: Fly a flight-spare LIS (Lightning Imaging Sensor) on ISS to take advantage of unique capabilities provided by the ISS (e.g., high inclination, real time data); Integrate LIS as a hosted payload on the DoD Space Test Program-Houston 5 (STP-H5) mission and launch on a Space X rocket for a minimum 2 year mission. Measurement: NASA and its partners developed and demonstrated effectiveness and value of using space-based lightning observations as a remote sensing tool; LIS measures lightning (amount, rate, radiant energy) with storm scale resolution, millisecond timing, and high detection efficiency, with no land-ocean bias. Benefit: LIS on ISS will extend TRMM (Tropical Rainfall Measuring Mission) time series observations, expand latitudinal coverage, provide real time data to operational users, and enable cross-sensor calibration.

LIS↗
NASA NTRS1980

Atmospheric solar absorption measurements in the 9 to 11 mu m region using a diode laser heterodyne spectrometer

A tunable diode laser heterodyne radiometer was developed for ground-based measurements of atmospheric solar absorption spectra in the 8 to 12 microns spectral range. The performance and operating characteristics of this Tunable Infrared Heterodyne Radiometer (TIHR) are discussed along with atmospheric solar absorption spectra of HNO3, O3, CO2, and H2O in the 9 to 11 microns spectral region.

Harward, C. N.↗
NASA NTRS1976

Technical and Economic Assessment of Span-Distributed Loading Cargo Aircraft Concepts

A 700,000 kg (1,540,000-lb) aircraft with a cruise Mach number of 0.75 was found to be optimum for the specified mission parameters of a 272 155-kg (600,000-lb) payload, a 5560-km (3000-n.mi.) range, and an annual productivity of 113 billion revenue-ton km (67 billion revenue-ton n. mi.). The optimum 1990 technology level spanloader aircraft exhibited the minimum 15-year life-cycle costs, direct operating costs, and fuel consumption of all candidate versions. Parametric variations of wing sweep angle, thickness ratio, rows of cargo, and cargo density were investigated. The optimum aircraft had two parallel rows of 2.44 x 2.44-m (8 x 8-ft) containerized cargo with a density of 160 kg/cu m (10 lb/ft 3) carried throughout the entire 101-m (331-ft) span of the constant chord, 22-percent thick, supercritical wing. Additional containers or outsized equipment were carried in the 24.4-m (80-ft) long fuselage compartment preceding the wing. Six 284,000-N (64,000-lb) thrust engines were mounted beneath the 0.7-rad (40-deg) swept wing. Flight control was provided by a 36.6-m (120-ft) span canard surface mounted atop the forward fuselage, by rudders on the wingtip verticals and by outboard wing flaperons.

Johnston, W. M.↗
NASA NTRS1972

Evaluation testing of a closed Brayton-cycle electrical-power-conversion system.

Description of the design and testing of a recuperated, closed Brayton-cycle, electrical power conversion system designated the Brayton Cycle Demonstrator (BCD). The system uses electrical heaters as a heat source, argon as the cycle working fluid, and gas-lubricated foil-type bearings. Objectives of the test program include (1) evaluation of the overall system performance characteristics and influences on spacecraft integration, (2) familiarization of personnel with operational methods, and (3) determination of system flexibility by operating at a number of off-design conditions. Results obtained to date are discussed.

Redding, T. E.↗
NASA NTRS1977

Earth orbital teleoperator mobility system evaluation program

The proximity translation and final docking of the space teleoperator evaluation vehicle (STEV) with large mass and small mass satellites was studied. Operations that may be performed by the STEV during the shuttle experiments are approximated.

Brye, R. G.↗
NASA NTRS1977

Use of experimental separation limits in the theoretical design of V/STOL inlets

Experimental data from several model inlets have been used to generate two parameters which are related to the limit of operation for inlet flow separation. One parameter, called the diffusion ratio, is the ratio of the peak velocity on the inlet surface to the velocity at the diffuser exit and is related to the boundary-layer separation at low throat Mach numbers. The other parameter, the peak Mach number on the inlet surface, is related to the separation at high throat Mach numbers. These parameters are easily calculated from potential flow solutions and thus can be used as a design tool in screening proposed inlet geometries. Any of the geometric design variables can be analyzed by this technique; but, this paper is restricted to the consideration of the internal lip contraction ratio. An illustrative example of an application to an inlet design study for a tilt nacelle VTOL airplane is presented. The study will show what value of contraction ratio is required to meet the operating requirements yet allow the inlet to remain free of separation as indicated by the two separation parameters.

Boles, M. A.↗
NASA NTRS1979

Far-infrared lasing in ruby

The feasibility of submillimeter wavelength (870 GHz) lasing in Al2O3 is discussed. The proposed scheme is based on the pumping of the 2A level of ruby via a ruby laser operating on its R2 line. Lasing is expected on the 2A to E transition of the split E-2 level.

Lawandy, N. M.↗