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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 865 records · Page 48
All sourcesNASA NTRSDOE OSTI
NASA NTRS1991

A general multiblock Euler code for propulsion integration. Volume 1: Theory document

A general multiblock Euler solver was developed for the analysis of flow fields over geometrically complex configurations either in free air or in a wind tunnel. In this approach, the external space around a complex configuration was divided into a number of topologically simple blocks, so that surface-fitted grids and an efficient flow solution algorithm could be easily applied in each block. The computational grid in each block is generated using a combination of algebraic and elliptic methods. A grid generation/flow solver interface program was developed to facilitate the establishment of block-to-block relations and the boundary conditions for each block. The flow solver utilizes a finite volume formulation and an explicit time stepping scheme to solve the Euler equations. A multiblock version of the multigrid method was developed to accelerate the convergence of the calculations. The generality of the method was demonstrated through the analysis of two complex configurations at various flow conditions. Results were compared to available test data. Two accompanying volumes, user manuals for the preparation of multi-block grids (vol. 2) and for the Euler flow solver (vol. 3), provide information on input data format and program execution.

Chen, H. C.↗
NASA NTRS1991

Multi-polarization C-band SAR for soil moisture estimation

Previous studies of synthetic aperture radar (SAR) imagery have shown qualitative relationships between radar backscatter and soil moisture. However, to be able to use these data in operational programs it will be necessary to establish quantitatively how the radar return is related to soil moisture and the effects of surface roughness, soil type, and vegetation cover and growth stage, as a function of frequency and polarization. To this end, a multi-year experiment began in 1990 as a cooperative venture amongst the Canada Center (Agriculture Canada), and the Universities of Guelph, Sherbrooke, Laval, and Waterloo. During 1990, SAR imagery was acquired during two periods (May and Jun.) to correspond to times of minimal and substantial vegetation cover. SAR data were acquired on three days in May and on four days in Jul. to cover different soil moisture conditions. This unique comprehensive data set is used to investigate the relationships between soil moisture and radar backscatter. The experiment and data collected are described, and a preliminary qualitative interpretation of the relationship between soil moisture and image tone is provided.

Brown, R. J.↗
NASA NTRS1990

An investigation of constraint-based component-modeling for knowledge representation in computer-aided conceptual design

Originally, computer programs for engineering design focused on detailed geometric design. Later, computer programs for algorithmically performing the preliminary design of specific well-defined classes of objects became commonplace. However, due to the need for extreme flexibility, it appears unlikely that conventional programming techniques will prove fruitful in developing computer aids for engineering conceptual design. The use of symbolic processing techniques, such as object-oriented programming and constraint propagation, facilitate such flexibility. Object-oriented programming allows programs to be organized around the objects and behavior to be simulated, rather than around fixed sequences of function- and subroutine-calls. Constraint propagation allows declarative statements to be understood as designating multi-directional mathematical relationships among all the variables of an equation, rather than as unidirectional assignments to the variable on the left-hand side of the equation, as in conventional computer programs. The research has concentrated on applying these two techniques to the development of a general-purpose computer aid for engineering conceptual design. Object-oriented programming techniques are utilized to implement a user-extensible database of design components. The mathematical relationships which model both geometry and physics of these components are managed via constraint propagation. In addition, to this component-based hierarchy, special-purpose data structures are provided for describing component interactions and supporting state-dependent parameters. In order to investigate the utility of this approach, a number of sample design problems from the field of aerospace engineering were implemented using the prototype design tool, Rubber Airplane. The additional level of organizational structure obtained by representing design knowledge in terms of components is observed to provide greater convenience to the program user, and to result in a database of engineering information which is easier both to maintain and to extend.

Kolb, Mark A.↗
NASA NTRS2015

The Role of the NASA Global Hawk Link Module as an Information Nexus For Atmospheric Mapping Missions

The Link Module described in this paper was developed for the NASA Uninhabited Aerial System (UAS) Global Hawk Pacific Mission (GloPAC) Airborne Science Campaign; four flights of 30 hour duration, supporting the Aura Validation Experiment (AVE). It was used again during the Genesis and Rapid Intensification Processes (GRIP) experiment, a NASA Earth Science field experiment to better understand how tropical storms form and develop into major hurricanes. In these missions, the Link Module negotiated all communication over the high bandwidth Ku satellite link, archived all the science data from onboard experiments in a spatially enabled database, routed command and control of the instruments from the Global Hawk Operations Center, and re-transmitted select data sets directly to experimenters control and analysis systems. The availability of aggregated information from collections of sensors, and remote control capabilities, in real-time, is revolutionizing the way Airborne Science is being conducted. The Link Module NG now being flown in support of the NASA Earth Venture missions, the Hurricane and Severe Storm Sentinel (HS3) mission, and Airborne Tropical Tropopause Experiment (A TTREX) mission, has advanced data fusion technologies that are further advancing the Scientific productivity, flexibility and robustness of these systems. On-the-fly traffic shaping has been developed to allow the high definition video, used for critical flight control segments, to dynamically allocate variable bandwidth on demand. Historically, the Link Module evolved from the instrument and communication interface controller used by NASA's Pathfinder and Pathfinder plus solar powered UAS's in the late 1990' s. It later was expanded for use in the AIRDAS four channel scanner flown on the NASA Altus UAS, and then again to a module in the AMS twelve channel multispectral scanner flying on the NASA (Predator-b) Ikhana UAS. The current system is the answer to the challenges imposed by extremely long duration UASs, with on-board multi-instrument (>= 12) Sensor Webs.

Hurricanes↗
NASA NTRS1994

Automated Instrumentation, Monitoring and Visualization of PVM Programs Using AIMS

We present views and analysis of the execution of several PVM codes for Computational Fluid Dynamics on a network of Sparcstations, including (a) NAS Parallel benchmarks CG and MG (White, Alund and Sunderam 1993); (b) a multi-partitioning algorithm for NAS Parallel Benchmark SP (Wijngaart 1993); and (c) an overset grid flowsolver (Smith 1993). These views and analysis were obtained using our Automated Instrumentation and Monitoring System (AIMS) version 3.0, a toolkit for debugging the performance of PVM programs. We will describe the architecture, operation and application of AIMS. The AIMS toolkit contains (a) Xinstrument, which can automatically instrument various computational and communication constructs in message-passing parallel programs; (b) Monitor, a library of run-time trace-collection routines; (c) VK (Visual Kernel), an execution-animation tool with source-code clickback; and (d) Tally, a tool for statistical analysis of execution profiles. Currently, Xinstrument can handle C and Fortran77 programs using PVM 3.2.x; Monitor has been implemented and tested on Sun 4 systems running SunOS 4.1.2; and VK uses X11R5 and Motif 1.2. Data and views obtained using AIMS clearly illustrate several characteristic features of executing parallel programs on networked workstations: (a) the impact of long message latencies; (b) the impact of multiprogramming overheads and associated load imbalance; (c) cache and virtual-memory effects; and (4significant skews between workstation clocks. Interestingly, AIMS can compensate for constant skew (zero drift) by calibrating the skew between a parent and its spawned children. In addition, AIMS' skew-compensation algorithm can adjust timestamps in a way that eliminates physically impossible communications (e.g., messages going backwards in time). Our current efforts are directed toward creating new views to explain the observed performance of PVM programs. Some of the features planned for the near future include: (a) ConfigView, showing the physical topology of the virtual machine, inferred using specially formatted IP (Internet Protocol) packets; and (b) LoadView, synchronous animation of PVM-program execution and resource-utilization patterns.

Mehra, Pankaj↗
NASA NTRS2011

Amine Swingbed Payload Project Management

The International Space Station (ISS) has been designed as a laboratory for demonstrating technologies in a microgravity environment, benefitting exploration programs by reducing the overall risk of implementing such technologies in new spacecraft. At the beginning of fiscal year 2010, the ISS program manager requested that the amine-based, pressure-swing carbon dioxide and humidity absorption technology (designed by Hamilton Sundstrand, baselined for the ORION Multi-Purpose Crew Vehicle, and tested at the Johnson Space Center in relevant environments, including with humans, since 2005) be developed into a payload for ISS Utilization. In addition to evaluating the amine technology in a flight environment before the first launch of the ORION vehicle, the ISS program wanted to determine the capability of the amine technology to remove carbon dioxide from the ISS cabin environment at the metabolic rate of the full 6-person crew. Because the amine technology vents the absorbed carbon dioxide and water vapor to space vacuum (open loop), additional hardware needed to be developed to minimize the amount of air and water resources lost overboard. Additionally, the payload system would be launched on two separate Space Shuttle flights, with the heart of the payload the swingbed unit itself launching a full year before the remainder of the payload. This paper discusses the project management and challenges of developing the amine swingbed payload in order to accomplish the technology objectives of both the open-loop ORION application as well as the closed-loop ISS application.

Hayley, Elizabeth↗
NASA NTRS2013

Amine Swingbed Payload Project Management

The International Space Station (ISS) has been designed as a laboratory for demonstrating technologies in a microgravity environment, benefitting exploration programs by reducing the overall risk of implementing such technologies in new spacecraft. At the beginning of fiscal year 2010, the ISS program manager requested that the amine-based, pressure-swing carbon dioxide and humidity absorption technology (designed by Hamilton Sundstrand, baselined for the Orion Multi-Purpose Crew Vehicle, and tested at the Johnson Space Center in relevant environments, including with humans, since 2005) be developed into a payload for ISS Utilization. In addition to evaluating the amine technology in a flight environment before the first launch of the Orion vehicle, the ISS program wanted to determine the capability of the amine technology to remove carbon dioxide from the ISS cabin environment at the metabolic rate of the full 6 ]person crew. Because the amine technology vents the absorbed carbon dioxide and water vapor to space vacuum (open loop), additional hardware needed to be developed to minimize the amount of air and water resources lost overboard. Additionally, the payload system would be launched on two separate Space Shuttle flights, with the heart of the payload-the swingbed unit itself-launching a full year before the remainder of the payload. This paper discusses the project management and challenges of developing the amine swingbed payload in order to accomplish the technology objectives of both the open -loop Orion application as well as the closed-loop ISS application.

Walsch, Mary↗
NASA NTRS2016

Human Flight to Lunar and Beyond - Re-Learning Operations Paradigms

For the first time since the Apollo era, NASA is planning on sending astronauts on flights beyond Low-Earth Orbit (LEO). The Human Space Flight (HSF) program started with a successful initial flight in Earth orbit, in December 2014. The program will continue with two Exploration Missions (EM) to Lunar orbit: EM-1 will be unmanned and EM-2, carrying astronauts, will follow. NASA established a multi-center team to address the communications, and related navigation, needs. This paper will focus on the lessons learned in the team, planning for the missions' parts that are beyond Earth orbit. Many of these lessons had to be re-learned, as the HSF program after operated for many years in Earth orbit. Fortunately, the experience base from tracking robotic missions in deep space by the Deep Space Network (DSN) and close interaction with the HSF community to understand the unique needs (e.g. 2-way voice) resulted in a ConOps that leverages of both the deep space robotic and the Human LEO experiences. Several examples will be used to highlight the unique operational needs for HSF missions beyond Earth Orbit, including: - Navigation. At LEO, HSF missions can rely on Global Positioning System (GPS) devices for orbit determination. For Lunar-and-beyond HSF missions, techniques such as precision 2-way and 3-way Doppler and ranging, Delta-Difference-of-range, and eventually on-board navigation will be used. - Impact of latency - the delay associated with Round-Trip-Light-Time (RTLT). Imagine trying to have a 2-way discussion (audio or video) with an astronaut, with a 2-3 sec delay inserted (for Lunar distances) or 20 minutes delay (for Mars distances). - Balanced communications link. For robotic missions, there has been a heavy emphasis on the downlink data rates, bringing back science data from the instruments on-board the spacecraft. Uplink data rates were of secondary importance, used to send commands to the spacecraft. The ratio of downlink-to-uplink data rates was often 10:1 or more. For HSF, rates for uplink and downlink, at least for high-quality video, need to be similar.

Kenny, Ted↗
NASA NTRSDate not supplied

Growing Beyond Earth: Student Citizen Science Contributing to Space Crop Production

Fairchild Tropical Botanic Garden and NASA have been partnering since 2015 to conduct a citizen science education program for middle and high school students called Growing Beyond Earth (GBE). Growing Beyond Earth is a multi-classroom science project designed to advance NASA’s research on growing plants in space. GBE was implemented locally and scaled nationally under two NASA Grants. Now serving more than 250 schools and over 10,000 middle and high school students nationwide, GBE successfully improved STEM education. It also contributed student-generated data to NASA, improving NASA research on the ground and on ISS, with two student-selected crops grown in space. GBE is unique in its focus on real scientific research, enabling student “citizen scientists” to contribute data toward NASA mission planning. Each classroom receives a Fairchild-designed plant habitat analogous to the plant growing equipment aboard the International Space Station (ISS). Fairchild and NASA scientists train teachers to conduct in-classroom GBE experiments, and students then share experimental data online with NASA. As NASA looks toward a long-term human presence beyond Earth’s orbit, there are specific science, technology, engineering, and math challenges related to food production in space. During this presentation, learn how GBE is addressing those challenges by expanding the diversity and quality of edible plants that can be grown aboard spacecraft. We will share the significant scientific and educational results that have come out of this partnership and explain how we quickly pivoted to allow students to continue to contribute during the COVID-era. Finally, we will explain how on Earth, GBE is also advancing technologies for growing plants in urban, indoor, and other resource-limited settings through the GBE Maker challenge for High School, University, and Professional communities of Makers across the country to develop the next generation of space crop production technologies. These programs are supported by NASA.

Growing Beyond Earth↗
DOE OSTI2026

Wyoming Trails Carbon Hub (WyoTCH)

The Wyoming Trails Carbon Hub (WyoTCH) project completed a front-end engineering and design (FEED) study for a commercial-scale, open-access carbon dioxide (CO 2 ) transport pipeline in Wyoming under U.S. Department of Energy (DOE) Award DEFE0032347, funded through the Bipartisan Infrastructure Law Carbon Capture Technology Program and administered by the National Energy Technology Laboratory. The project’s approach of designing a multi-source, multi-destination pipeline, rather than a dedicated line serving a single project, would lower the barrier to entry for individual CO 2 projects. The projects would leverage Wyoming's concentrated industrial and power generation CO 2 sources, its existing CO 2 pipeline infrastructure, and its extensive CO 2 storage and utilization capacity. This is the project's final technical report.

01 COAL, LIGNITE, AND PEAT↗
NASA NTRS1984

Simulation requirements for the Large Deployable Reflector (LDR)

Simulation tools for the large deployable reflector (LDR) are discussed. These tools are often the transfer function variety equations. However, transfer functions are inadequate to represent time-varying systems for multiple control systems with overlapping bandwidths characterized by multi-input, multi-output features. Frequency domain approaches are the useful design tools, but a full-up simulation is needed. Because of the need for a dedicated computer for high frequency multi degree of freedom components encountered, non-real time smulation is preferred. Large numerical analysis software programs are useful only to receive inputs and provide output to the next block, and should be kept out of the direct loop of simulation. The following blocks make up the simulation. The thermal model block is a classical heat transfer program. It is a non-steady state program. The quasistatic block deals with problems associated with rigid body control of reflector segments. The steady state block assembles data into equations of motion and dynamics. A differential raytrace is obtained to establish a change in wave aberrations. The observation scene is described. The focal plane module converts the photon intensity impinging on it into electron streams or into permanent film records.

Soosaar, K.↗
NASA NTRS1996

Simulation model of the F/A-18 high angle-of-attack research vehicle utilized for the design of advanced control laws

The 'f18harv' six degree-of-freedom nonlinear batch simulation used to support research in advanced control laws and flight dynamics issues as part of NASA's High Alpha Technology Program is described in this report. This simulation models an F/A-18 airplane modified to incorporate a multi-axis thrust-vectoring system for augmented pitch and yaw control power and actuated forebody strakes for enhanced aerodynamic yaw control power. The modified configuration is known as the High Alpha Research Vehicle (HARV). The 'f18harv' simulation was an outgrowth of the 'f18bas' simulation which modeled the basic F/A-18 with a preliminary version of a thrust-vectoring system designed for the HARV. The preliminary version consisted of two thrust-vectoring vanes per engine nozzle compared with the three vanes per engine actually employed on the F/A-18 HARV. The modeled flight envelope is extensive in that the aerodynamic database covers an angle-of-attack range of -10 degrees to +90 degrees, sideslip range of -20 degrees to +20 degrees, a Mach Number range between 0.0 and 2.0, and an altitude range between 0 and 60,000 feet.

Strickland, Mark E.↗
NASA NTRS1998

Mechanical System Analysis/Design Tool (MSAT) Quick Guide

MSAT is a unique multi-component multi-disciplinary tool that organizes design analysis tasks around object-oriented representations of configuration components, analysis programs and modules, and data transfer links between them. This creative modular architecture enables rapid generation of input stream for trade-off studies of various engine configurations. The data transfer links automatically transport output from one application as relevant input to the next application once the sequence is set up by the user. The computations are managed via constraint propagation - the constraints supplied by the user as part of any optimization module. The software can be used in the preliminary design stage as well as during the detail design of product development process.

Lee, HauHua↗
NASA NTRS2002

Global Precipitation Measurement: Summary of the First GPM Partners Planning Workshop - Report 1

This report provides a synopsis of the proceedings of the First Global Precipitation Measurement (GPM) Partners Planning Workshop held at the University of Maryland, College Park, from May 16 to 18, 2001. GPM consists of a multi-member global satellite constellation (i.e., an international set of satellite missions) and the accompanying scientific research program, with the main goal of providing frequent, accurate, and globally distributed precipitation measurements essential in understanding several fundamental issues associated with the global water and energy cycle (GWEC). The exchange of scientific and technical information at this and subsequent GPM workshops between representatives from around the world represents a key step in the formulation phase of GPM mission development. The U.S. National Aeronautics and Space Agency (NASA), the National Space Development Agency of Japan (NASDA), and other interested agencies from nations around the world seek to observe, understand, and model the Earth system to learn how it is changing and what consequences these changes have on life, particularly as they pertain to hydrological processes and the availability of fresh water resources. GWEN processes are central to a broader understanding of the Earth system.

Shepherd, J. Marshall↗
NASA NTRS2005

Atomic Oxygen Effects on Coated Tether Materials

The University of Alabama in Huntsville s Propulsion Research Center has teamed with NASA's Marshall Space Flight Center (MSFC) to research the effects of atomic oxygen (AO) bombardment on coated tether materials. Tethers Unlimited Inc. has provided several candidate tether materials with various coatings for (AO) exposure in MSFC's Atomic Oxygen Beam Facility. Additional samples were exposed to ultraviolet (UV) radiation at MSFC. AO erodes most organic materials, and ultraviolet radiation embrittles polymers. This test series was performed to determine the effect of AO and UV on the mechanical integrity of tether materials that were treated with AO-protective coatings, such as Photosil or metallization. Both TUI's Multi-Application Survivable Tether (MAST) Experiment and Marshall Space Flight Center's Momentum Exchange Electrodynamic Reboost (MXER) programs will benefit from this research by helping to determine tether materials and coatings that give the longest life with the lowest mass penalty.

Gittemeier, Keith A.↗
NASA NTRS2005

Space Environmental Effects on Coated Tether Materials

The University of Alabama in Huntsville s Propulsion Research Center has teamed with NASA's Marshall Space Flight Center (MSFC) to research the effects of atomic oxygen (AO) bombardment on coated tether materials. Tethers Unlimited Inc. has provided several candidate tether materials with various coatings for AO exposure in MSFC s Atomic Oxygen Beam Facility. Additional samples were exposed to ultraviolet (UV) radiation at MSFC. AO erodes most organic materials, and ultraviolet radiation embrittles polymers. This test series was performed to determine the effect of AO and UV on the mechanical integrity of tether materials that were treated with AO-protective coatings, such as polyhedral oligomeric silsesquioxane (POSS) or metallization. Both TUI's Multi-Application Survivable Tether (MAST) Experiment and Marshall Space Flight Center s Momentum Exchange Electrodynamic Reboost (MXER) programs will benefit from this research by helping to determine tether materials and coatings that give the longest life with the lowest mass penalty.

Gittemeier, Keith A.↗
NASA NTRS1996

The Hubble Space Telescope Extragalactic Distance Scale Key Project. X. The Cepheid Distance to NGC 7331

The distance to NGC 7331 has been derived from Cepheid variables observed with HST/WFPC2, as part of the Extragalactic Distance Scale Key Project. Multi-epoch exposures in F555W(~V) and F814W (~1), with photometry derived independently from DoPHOT and DAOPHOT/ALLFRAME programs, which were used to detect a total of 14 reliable Cepheids, with periods between 11 and 42 days.

Cepheids galaxies distances redshifts NGC 7331 ear↗
NASA NTRS2006

Sequencing System Building Blocks: Using a Component Architecture for Sequencing Software

Over the last few years software engineering has made significant strides in making more flexible architectures and designs possible. However, at the same time, spacecraft have become more complex and flight software has become more sophisticated. Typically spacecraft are often one-of-a-kind entities that have different hardware designs, different capabilities, different instruments, etc. Ground software has become more complex and operations teams have had to learn a myriad of tools that all have different user interfaces and represent data in different ways. At Jet Propulsion Laboratory (JPL) these themes have collided to require a new approach to producing ground system software. Two different groups have been looking at tackling this particular problem. One group is working for the JPL Mars Technology Program in the Mars Science Laboratory (MSL) Focused Technology area. The other group is the JPL Multi-Mission Planning and Sequencing Group. The major concept driving these two approaches on a similar path is to provide software that can be a more cohesive flexible system that provides a set of planning and sequencing system of services. This paper describes the efforts that have been made to date to create a unified approach from these disparate groups.

multi mission planning↗