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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 703 records · Page 39
All sourcesNASA NTRSDOE OSTI
NASA NTRS1979

Advanced System Design Requirements for Large and Small Fixed-wing Aerial Application Systems for Agriculture

Several candidate aircraft configurations were defined over the range of 1000 to 10,000 pounds payload and evaluated over a broad spectrum of agricultural missions. From these studies, baseline design points were selected at 3200 pounds payload for the small aircraft and 7500 pounds for the large aircraft. The small baseline aircraft utilizes a single turboprop powerplant while the large aircraft utilizes two turboprop powerplants. These configurations were optimized for wing loading, aspect ratio, and power loading to provide the best mission economics in representative missions. Wing loading of 20 lb/sq ft was selected for the small aircraft and 25 lb/sq ft for the large aircraft. Aspect ratio of 8 was selected for both aircraft. It was found that a 10% reduction in engine power from the original configurations provided improved mission economics for both aircraft by reducing the cost of the turboprop. Refined configurations incorporate a 675 HP engine in the small aircraft and two 688 HP engines in the large aircraft.

Hinely, J. T., Jr.↗
NASA NTRSDate not supplied

NASA Small Spacecraft and Distributed Systems: Recent and Upcoming Technology Demonstrations and Development Efforts

NASA’s Small Spacecraft & Distributed Systems (SSDS) program strengthens U.S. ability to conduct unique missions by rapidly developing and demonstrating capabilities for SmallSat exploration, science, and commercial space. In collaboration with NASA Centers, other government agencies, commercial industry, and academia, SSDS advances next generation SmallSat technologies like power, processing, propulsion, communications, autonomous navigation, architectures (swarms), and applications (AI/ML/Edge Computing)—to extend missions beyond LEO into cislunar and planetary space. Various investment mechanisms exist for SSDS to select and fund projects that will ultimately advance NASA’s Moon to Mars Architecture. Presented here are the latest achievements and findings from recently completed SSDS projects, along with updates from ongoing efforts and planned future work. Successful missions like Starling and CAPSTONE continue to demonstrate their capability after several years on-orbit. Advancements in next generation swarm configurations are being implemented by Starling for space traffic monitoring and management applications. Findings from recent SSDS flight projects are discussed: DiskSat, a unique SmallSat platform alternative to canisterized nanosatellites, launched December 2025 and is gathering data; the PTD series of missions concluded in December 2025. Current SSDS efforts are focused on addressing NASA Shortfalls relating to rendezvous and proximity operations, neuromorphic computing, and space situational awareness.

Roger Hunter↗
DOE OSTI2014

Collective outflow from a small multiple stellar system

The formation of high-mass stars is usually accompanied by powerful protostellar outflows. Such high-mass outflows are not simply scaled-up versions of their lower-mass counterparts, since observations suggest that the collimation degree degrades with stellar mass. Theoretically, the origins of massive outflows remain open to question because radiative feedback and fragmentation of the accretion flow around the most massive stars, with M > 15 M {sub ☉}, may impede the driving of magnetic disk winds. We here present a three-dimensional simulation of the early stages of core fragmentation and massive star formation that includes a subgrid-scale model for protostellar outflows. We find that stars that form in a common accretion flow tend to have aligned outflow axes, so that the individual jets of multiple stars can combine to form a collective outflow. We compare our simulation to observations with synthetic H{sub 2} and CO observations and find that the morphology and kinematics of such a collective outflow resembles some observed massive outflows, such as Cepheus A and DR 21. We finally compare physical quantities derived from simulated observations of our models to the actual values in the models to examine the reliability of standard methods for deriving physical quantities, demonstrating that those methods indeed recover the actual values to within a factor of two to three.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2012

Using Micro-Electro-Mechanical Systems (MEMS) as Small Antennas

We describe the design, fabrication and characterization of simple micromechanical structures that are capable of sensing static electric time varying electromagnetic fields. Time varying electric field sensing is usually achieved using an electromagnetic antenna and a receiver. However, these antenna-based approaches do not exhibit high sensitivity over a broad frequency (or wavelength) range. An important aspect of the present work is that, in contrast to traditional antennas, the dimensions of these micromechanical oscillators can be much smaller than the wavelength of the electromagnetic wave. We characterized the fabricated micromechanical oscillators by measuring their responses to time varying electric and electromagnetic fields.

Datskos, Panos G↗
DOE OSTI2017

An Early Survey of Best Practices for the Use of Small Unmanned Aerial Systems by the Electric Utility Industry

This technical manual is about doing things safely. It isn’t so much a how-to guide as it is a collection of best practices from unmanned aerial system (UAS) operators from all over the world. The desired end state is to provide a touchstone for utility businesses, directors, managers, and operators that will inform them as they begin to strategize, plan, and incorporate this technology into day-to-day operations.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2023

Flow rate optimization for a small liquid argon system at Fermilab.

This analysis highlights the dominant role of pressure loss in filter disks, emphasizing its crucial consideration during the design phase to ensure optimal fluid flow. Additionally, the significance of vapor quality at the transfer line inlet is identified as a key factor impacting the fill rate. Reducing inlet vapor quality and exploring the use of subcooled liquid are recommended approaches to enhance system performance.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2024

Data collected using small uncrewed aircraft systems during the TRacking Aerosol Convection interactions ExpeRiment (TRACER)

Abstract. The main goal of the TRacking Aerosol Convection interactions ExpeRiment (TRACER) project was to further understand the role that regional circulations and aerosol loading play in the convective cloud life cycle across the greater Houston, Texas, area. To accomplish this goal, the United States Department of Energy and research partners collaborated to deploy atmospheric observing systems across the region. Cloud and precipitation radars, radiosondes, and air quality sensors captured atmospheric and cloud characteristics. A dense lower-atmospheric dataset was developed using ground-based remote sensors, a tethersonde, and uncrewed aerial systems (UASs). TRACER-UAS is a subproject that deployed two UAS platforms to gather high-resolution observations in the lower atmosphere between 1 June and 30 September 2022. The University of Oklahoma CopterSonde and the University of Colorado Boulder RAAVEN (Robust Autonomous Aerial Vehicle – Endurant Nimble) were flown at two coastal locations between the Gulf of Mexico and Houston. The University of Colorado Boulder RAAVEN gathered measurements of atmospheric thermodynamic state, winds and turbulence, and aerosol size distribution. Meanwhile, the University of Oklahoma CopterSonde system operated on a regular basis to resolve the vertical structure of the thermodynamic and kinematic state. Together, a complementary dataset of over 200 flight hours across 61 d was generated, and data from each platform proved to be in strong agreement. In this paper, the platforms and respective data collection and processing are described. The dataset described herein provides information on boundary layer evolution, the sea breeze circulation, conditions prior to and nearby deep convection, and the vertical structure and evolution of aerosols. The quality-controlled TRACER-UAS observations from the CopterSonde and RAAVEN can be found at https://doi.org/10.5439/1969004 (Lappin, 2023) and https://doi.org/10.5439/1985470 (de Boer, 2023), respectively.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1978

A small gas inlet system for orbital mass-spectrometer calibrations

A gas inlet system is described for generating precise gas pressures that are to be used as calibration references for the mass spectrometers aboard the dual air density Explorer satellites. This gas inlet system was developed as an inflight calibration technique in which a known amount of onboard gas is released in the satellite cavity and is detected by the mass spectrometer. Although several flight mass spectrometer experiments have been proposed, none make use of the inflight calibration technique described in this report. Laboratory measurements and calibration of the metering leak technique for the gas inlet systems are discussed. The systems tested have metering leak rates between 2 and 4 microliters/sec at 298 K for argon-40, and they produce molecular flow up to 100 torr, which is the highest test pressure in this experiment. Test data show that metering leak rates are reproducible within 1 percent of established means for helium-3, helium-4, and argon-40.

Smith, A.↗
NASA NTRS1986

Infrared observations of small solar-system bodies

Observations of Europa using the Cooled Grating Array Spectrometer have resulted in the discovery of new absorption features in the spectrum of the trailing side of Europa which have been attributed to either magnetospherically implanted sulfur compounds or recently emplaced hydrates of ammonia. More observations are planned to determine which of these two classes of compounds are responsible. Two asteroid occultations have been observed so far, but with some negative results (the occultations paths shifted sufficiently that the groups responsible for timing the visual occultation got no data). High-quality data in the thermal infrared were obtained nevertheless; those data are useful for constraint of thermal models of asteroids and will be analyzed in that context. Work was completed to perfect a computer code that will fit a triaxial-ellipsoid thermal model to the IR data while constrained by the visual lightcurve.

Brown, R. H.↗
NASA NTRS1988

Infrared observations of small solar-system bodies

A major accomplishment during last year is the recongition of and modeling of the solid-state greenhouse effect for icy satellites. Recent observations of eclipse reappearances suggest that this effect may in fact be observed on Europa and Ganymede. Also the PI has obtained important new data on Europa and Enceladus. Evidence for the transient presence of a volatile, perhaps NH3, OH, on Europa has been obtained. Newly obtained spectra of Enceladus suggest that it does not at present have ammonia or methane in detectable quantities on its surface.

Brown, R. H.↗
NASA NTRS1992

Satellite communications application to Pacific countries above Ku band

An application of satellite communications above the Ku band to the Pacific region is described, focusing on: (1) Lightsat system and (2) a high capacity satellite system. A small geostationary satellite system using Ku band for the Federated States of Micronesia is shown as an example. A concept of multi-gigabits/second high capacity communications system using two satellites in the Ka band is described. The onboard bit-by-bit processing is very useful in the low link margin environment due to rain attenuation. These topics were obtained by the Asia Pacific Telecommunications Study granted by NASA conducted by the University of Colorado at Boulder.

Iida, Takashi↗
NASA NTRS1998

Structural Analysis of Components of the Students for the Exploration and Development of Space Satellite (SEDSAT) for the Small Expendable Deployer System (SEDS) Project Office

During the time frame allocated by the delivery order, members of the UAH Applied Research Program, with the cooperation of representatives from NASA investigated and conducted stress analysis of the SEDSAT1 satellite. The main area of concern was with the design of the deployable 10 m antennas. The placement of the holes for the antenna door hinge pin was too close to the edge of the antenna canister. Because of the load placed on the hinge pin, the stress analysis of this area suggested that more space would be needed between the holes and the edge of the material. Due to other conflicts, SEDSATI was removed from flying on the space shuttle and moved to the Delta Launch Vehicle. This changed many of the design requirements for the mounting and deployment of the satellite that forced a new design for the satellite. Once this happened, the stress analysis became obsolete, and the task was concluded.

Maddux, Gary A.↗
NASA NTRS1999

Propulsive Small Expendable Deployer System (ProSEDS) Experiment

ProSEDS is a secondary (i.e. piggyback) payload on a Delta-11 GPS 8 mission scheduled for launch in August 2000. It will test the feasibility of generating generate electrodynamic thrust without propellant using a 5 kilometer conducting wire (tether). The ProSEDS obtains thrust as the tether cuts across the magnetic field, a voltage is induced across the wire. Electrons are attracted to the positively based far end of the wire. Electrons flow downward through the conductive tether. Earth's magnetic field exerts a drag force on the current in the tether segments, that is mechanically transferred via the wire to the stage. The primary objective for the ProSEDs mission is to demonstrate that a significant, measurable electrodynamic thrust through a tether in space. The primary mission will last one day, as the primary battery assures at least three orbits of data will be collected, the remaining power will be provided by the secondary battery, which uses tether generated power to recharge. The extended mission begins using the power provided through the tether, and wil terminate when a system ceases to function; (i.e., either degradation of the tether,through Atomic Oxygen contact, a micrometeoroid or other debris impact, or another malfunction.) The technology has many potential applications. Amongst the applications, which are reviewed in detail, are: (1) satellite deorbit, (2) reboost of the International Space Station, (3) propellantless reusable Orbit Transfer Vehicles, (4) Propulsion and power generation for future Jovian missions.

Johnson, Les↗