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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 NTRS1992

Space plasma physics at the Applied Physics Laboratory over the past half-century

An overview is given of space-plasma experiments conducted at the Applied Physics Laboratory (APL) at Johns Hopkins University including observational campaigns and the instrumentation developed. Specific space-plasma experiments discussed include the study of the radiation environment in the Van Allen radiation belt with solid-state proton detectors. Also described are the 5E-1 satellites which acquired particle and magnetic-field data from earth orbit. The Triad satellite and its magnetometer system were developed for high-resolution studies of the earth's magnetic field, and APL contributions to NASA's Interplanetary Monitoring Platforms are listed. The review mentions the International Ultraviolet Explorer, the Atmosphere Explorer mission, and the Active Magnetic Particle Tracer Explorers mission. Other recent programs reviewed include a high-latitude satellite, contributions to the Voyager mission, and radar studies of space plasmas.

Potemra, Thomas A.↗
NASA NTRS2006

Applied Physics Lab Kennedy Space Center: Recent Contributions

The mission of the Applied Physics Lab is: (1) Develop and deliver novel sensors and devices to support KSC mission operations. (2) Analyze operational issues and recommend or deliver practical solutions. (3) Apply physics to the resolution of long term space flight issues that affect space port operation on Earth or on other planets.

Starr, Stan↗
NASA NTRS2010

Selected KSC Applied Physics Lab Responses to Shuttle Processing Measurement Requests

The KSC Applied Physics Lab has been supporting Shuttle Ground Processing for over 20 years by solving problems brought to us by Shuttle personnel. Roughly half of the requests to our lab have been to find ways to make measurements, or to improve on an existing measurement process. This talk will briefly cover: 1) Centering the aft end of the External Tank between the Solid Rocket Boosters; 2) Positioning the GOX Vent Hood over the External Tank; 3) Remote Measurements of External Tank Damage; 4) Strain Measurement in the Orbiter Sling; and 5) Over-center Distance Measurement in an Over-center Mechanism.

Youngquist, Robert C.↗
NASA NTRS2000

First-Order Model Management With Variable-Fidelity Physics Applied to Multi-Element Airfoil Optimization

First-order approximation and model management is a methodology for a systematic use of variable-fidelity models or approximations in optimization. The intent of model management is to attain convergence to high-fidelity solutions with minimal expense in high-fidelity computations. The savings in terms of computationally intensive evaluations depends on the ability of the available lower-fidelity model or a suite of models to predict the improvement trends for the high-fidelity problem, Variable-fidelity models can be represented by data-fitting approximations, variable-resolution models. variable-convergence models. or variable physical fidelity models. The present work considers the use of variable-fidelity physics models. We demonstrate the performance of model management on an aerodynamic optimization of a multi-element airfoil designed to operate in the transonic regime. Reynolds-averaged Navier-Stokes equations represent the high-fidelity model, while the Euler equations represent the low-fidelity model. An unstructured mesh-based analysis code FUN2D evaluates functions and sensitivity derivatives for both models. Model management for the present demonstration problem yields fivefold savings in terms of high-fidelity evaluations compared to optimization done with high-fidelity computations alone.

Alexandrov, N. M.↗
NASA NTRS1969

Applied physics

Infrared converter, photoluminescence in CdS thin films, tunneling barriers, ionization gage and electrical-discharge machining studies

Anner, G. E.↗
NASA NTRS2013

Recent Projects in the KSC Applied Physics Lab

Topics include: Shuttle heritage; ISRU /RESOLVE: a) Payload for Lunar Lander/Rover on Polar Areas of Moon. b) Avionics/Software. New Technologies for Exploration: a) Radiation Shielding work. b) Cooperative Tractor Beams.

Starr, Stanley↗
NASA NTRS2005

Verification, Validation, and Solution Quality in Computational Physics: CFD Methods Applied to Ice Sheet Physics

Procedures and methods for veri.cation of coding algebra and for validations of models and calculations used in the aerospace computational fluid dynamics (CFD) community would be ef.cacious if used by the glacier dynamics modeling community. This paper presents some of those methods, and how they might be applied to uncertainty management supporting code veri.cation and model validation for glacier dynamics. The similarities and differences between their use in CFD analysis and the proposed application of these methods to glacier modeling are discussed. After establishing sources of uncertainty and methods for code veri.cation, the paper looks at a representative sampling of veri.cation and validation efforts that are underway in the glacier modeling community, and establishes a context for these within an overall solution quality assessment. Finally, a vision of a new information architecture and interactive scienti.c interface is introduced and advocated.

Thompson, David E.↗
NASA NTRS1987

Overview of CFD validation experiments

The topics are presented in viewgraph form and include the following: fundamental physics validation experiments; applied physics validation experiments; physical flow phenomena; boundary layer tunnel; boundary layer research; centrifugal compressors; centrifugal compressor flow phenomena; turbomachinery computational fluid dynamics (CFD) validation; inlet, duct, and nozzle CFD validation; and chemical reacting flows CFD validation.

Povinelli, Louis A.↗
NASA NTRS2004

Stirling Microregenerators Fabricated and Tested

A mesoscale Stirling refrigerator patented by the NASA Glenn Research Center is currently under development. This refrigerator has a predicted efficiency of 30 percent of Carnot and potential uses in electronics, sensors, optical and radiofrequency systems, microarrays, and microsystems. The mesoscale Stirling refrigerator is most suited to volume-limited applications that require cooling below the ambient or sink temperature. Primary components of the planar device include two diaphragm actuators that replace the pistons found in traditional-scale Stirling machines and a microregenerator that stores and releases thermal energy to the working gas during the Stirling cycle. Diaphragms are used to eliminate frictional losses and bypass leakage concerns associated with pistons, while permitting reversal of the hot and cold sides of the device during operation to allow precise temperature control. Three candidate microregenerators were fabricated under NASA grants for initial evaluation: two constructed of porous ceramic, which were fabricated by Johns Hopkins Applied Physics Laboratory, and one made of multiple layers of nickel and photoresist, which was fabricated by Polar Thermal Technologies. The candidate regenerators are being tested by Johns Hopkins Applied Physics in a custom piezoelectric-actuated test apparatus designed to produce the Stirling refrigeration cycle. In parallel with the regenerator testing, Johns Hopkins is using deep reactive ion etching to fabricate electrostatically driven, comb-drive diaphragm actuators. These actuators will drive the Stirling cycle in the prototype device. The top photograph shows the porous ceramic microregenerators. Two microregenerators were fabricated with coarse pores and two with fine pores. The bottom photograph shows the test apparatus parts for evaluating the microregenerators, including the layered nickel-and-photoresist regenerator fabricated using LIGA techniques.

Moran, Matthew E.↗
NASA NTRS2004

Computational Physics for Space Flight Applications

This paper presents viewgraphs on computational physics for space flight applications. The topics include: 1) Introduction to space radiation effects in microelectronics; 2) Using applied physics to help NASA meet mission objectives; 3) Example of applied computational physics; and 4) Future directions in applied computational physics.

Reed, Robert A.↗
NASA NTRS2002

Hot Meetings

A colleague walked by my office one time as I was conducting a meeting. There were about five or six members of my team present. The colleague, a man who had been with our institution (The Johns Hopkins Applied Physics Lab, a.k.a. APL) for many years, could not help eavesdropping. He said later it sounded like we we re having a raucous argument, and he wondered whether he should stand by the door in case things got out of hand and someone threw a punch. Our Advanced Composition Explorer (ACE) team was a hot group, to invoke the language that is fashionable today, although we never thought of ourselves in those terms. It was just our modus operandi. The tenor of the discussion got loud and volatile at times, but I prefer to think of it as animated, robust, or just plain collaborative. Mary Chiu and her "hot" team from the Johns Hopkins Applied Physics Laboratory built the Advanced Composition Explorer spacecraft for NASA. Instruments on the spacecraft continue to collect data that inform us about what's happening on our most important star, the Sun.

Chiu, Mary↗
NASA NTRS2008

Architecture Study on Telemetry Coverage for Immediate Post-Separation Phase

This paper presents the preliminary results of an architecture study that provides continuous telemetry coverage for NASA missions for immediate post-separation phase. This study is a collaboration effort between Jet Propulsion Laboratory (JPL), Goddard Space Flight Center (GSFC), and Applied Physics Laboratory (APL). After launch when the spacecraft separated from the upper stage, the spacecraft typically executes a number of mission-critical operations prior to the deployment of solar panels and the activation of the primary communication subsystem. JPL, GSFC, and APL have similar design principle statements that require continuous coverage of mission-critical telemetry during the immediate post-separation phase. To conform to these design principles, an architecture that consists of a separate spacecraft transmitter and a robust communication network capable of tracking the spacecraft signals is needed.This paper presents the preliminary results of an architecture study that provides continuous telemetry coverage for NASA missions for immediate post-separation phase. This study is a collaboration effort between Jet Propulsion Laboratory (JPL), Goddard Space Flight Center (GSFC), and Applied Physics Laboratory (APL). After launch when the spacecraft separated from the upper stage, the spacecraft typically executes a number of mission-critical operations prior to the deployment of solar panels and the activation of the primary communication subsystem. JPL, GSFC, and APL have similar design principle statements that require continuous coverage of mission-critical telemetry during the immediate post-separation phase. To conform to these design principles, an architecture that consists of a separate spacecraft transmitter and a robust communication network capable of tracking the spacecraft signals is needed. The main results of this study are as follows: 1) At low altitude (< 10000 km) when most post-separation critical operations are executed, Earth-based network (e.g. Deep Space Network (DSN)) can only provide limited coverage, whereas space-based network (e.g. Space Network (SN)) can provide continuous coverage. 2) Commercial-off-the-shelf SN compatible transmitters are available for small satellite applications. In this paper we present the detailed coverage analysis of Earth-based and Space-based networks. We identify the key functional and performance requirements of the architecture, and describe the proposed selection criteria of the spacecraft transmitter. We conclude the paper with a proposed forward plan.

architecture↗
NASA NTRS2003

Development Efforts Expanded in Ion Propulsion: Ion Thrusters Developed With Higher Power Levels

The NASA Glenn Research Center was the major contributor of 2-kW-class ion thruster technology to the Deep Space 1 mission, which was successfully completed in early 2002. Recently, NASA s Office of Space Science awarded approximately $21 million to Glenn to develop higher power xenon ion propulsion systems for large flagship missions such as outer planet explorers and sample return missions. The project, referred to as NASA's Evolutionary Xenon Thruster (NEXT), is a logical follow-on to the ion propulsion system demonstrated on Deep Space 1. The propulsion system power level for NEXT is expected to be as high as 25 kW, incorporating multiple ion thrusters, each capable of being throttled over a 1- to 6-kW power range. To date, engineering model thrusters have been developed, and performance and plume diagnostics are now being documented. The project team-Glenn, the Jet Propulsion Laboratory, General Dynamics, Boeing Electron Dynamic Devices, the Applied Physics Laboratory, the University of Michigan, and Colorado State University-is in the process of developing hardware for a ground demonstration of the NEXT propulsion system, which comprises a xenon feed system, controllers, multiple thrusters, and power processors. The development program also will include life assessments by tests and analyses, single-string tests of ion thrusters and power systems, and finally, multistring thruster system tests in calendar year 2005. In addition, NASA's Office of Space Science selected Glenn to lead the development of a 25-kW xenon thruster to enable NASA to conduct future missions to the outer planets of Jupiter and beyond, under the High Power Electric Propulsion (HiPEP) program. The development of a 100-kW-class ion propulsion system and power conversion systems are critical components to enable future nuclear-electric propulsion systems. In fiscal year 2003, a team composed of Glenn, the Boeing Company, General Dynamics, the Applied Physics Laboratory, the Naval Research Laboratory, the University of Wisconsin, the University of Michigan, and Colorado State University will perform a 6-month study that will result in the design of a 25-kW ion thruster, a propellant feed system, and a power processing architecture. The following 2 years will involve hardware development, wear tests, single-string tests of the thruster-power circuits and the xenon feed system, and subsystem service life analyses. The 2-kW-class ion propulsion technology developed for the Deep Space 1 mission will be used for NASA's discovery mission Dawn, which involves maneuvering a spacecraft to survey the asteroids Ceres and Vesta. The 6-kW-class ion thruster subsystem technology under NEXT is scheduled to be flight ready by calendar year 2006. The less mature 25- kW ion thruster system under HiPEP is expected to be ready for a flight advanced development program in calendar year 2006.

Patterson, Michael J.↗
NASA NTRS2007

International Space Station Research: Accomplishments and Pathways for Exploration and Fundamental Research

Beginning with the launch of the European Columbus module planned for December 2007, we approach a transition in the assembly of the International Space Station (ISS) that is of great importance for the sciences. During the following 18 months, we will operate the first experiments in Columbus physical science resource facilities and also launch and commission the Japanese Kibo module. In addition, two Multi-purpose Logistics Module (MPLM) flights will deliver the U.S. Combustion Integrated Rack (CIR) and Fluids Integrated Rack (FIR) along with their first science experiments. These facilities provide significant new capabilities for basic and applied physical science research in microgravity. New life support technologies will come online throughout 2008, and we will reach the milestone of a 6-person crew planned for April 2009. A larger crew enables significant more scientific use of all the facilities for the life of ISS. Planning for the use of the International Space Station as a national laboratory is also maturing as we near the completion of assembly, enabling access to ISS as a research platform for other government agencies and the private sector. The latest updates on National Laboratory implementation will also be provided in this presentation. At the same time as these significant increases in scientific capability, there have been significant ongoing accomplishments in NASA's early ISS research both exploration related and fundamental research. These accomplishments will be reviewed in context as harbingers of the capabilities of the International Space Station when assembly is complete. The Vision for Space Exploration serves to focus NASA's applied investigations in the physical sciences. However, the broader capability of the space station as a National Laboratory and as a nexus for international collaboration will also influence the study of gravity-dependent processes by researchers around the world.

Robinson, Julie A.↗