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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 1,765 records · Page 98
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Computer simulation of thermal and fluid systems for MIUS integration and subsystems test /MIST/ laboratory

This paper describes the application of the SINDA (systems improved numerical differencing analyzer) computer program to simulate the operation of the NASA/JSC MIUS integration and subsystems test (MIST) laboratory. The MIST laboratory is designed to test the integration capability of the following subsystems of a modular integrated utility system (MIUS): (1) electric power generation, (2) space heating and cooling, (3) solid waste disposal, (4) potable water supply, and (5) waste water treatment. The SINDA/MIST computer model is designed to simulate the response of these subsystems to externally impressed loads. The computer model determines the amount of recovered waste heat from the prime mover exhaust, water jacket and oil/aftercooler and from the incinerator. This recovered waste heat is used in the model to heat potable water, for space heating, absorption air conditioning, waste water sterilization, and to provide for thermal storage. The details of the thermal and fluid simulation of MIST including the system configuration, modes of operation modeled, SINDA model characteristics and the results of several analyses are described.

Rochelle, W. C.↗
DOE OSTI2022

Eigenstate thermalization and disappearance of quantum many-body scar states in weakly interacting fermion systems

The recent discovery of quantum many-body scar states has revealed the possibility of having states with low entanglement that violate the eigenstate thermalization hypothesis in nonintegrable systems. Eigenstates with low entanglement entropy are rare but naturally exist in the integrable system of free fermions. Here, we demonstrate analytically that these atypical states would be always eliminated when an arbitrary weak interaction is introduced between the fermions. In particular, we show that the probability of having a many-body scar state with entanglement entropy satisfying a sub-volume scaling law decreases double exponentially as the system size. Furthermore, our results provide a quantitative argument for the disappearance of scar states in interacting fermion systems.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
NASA NTRS1977

Regenerative Life Support Evaluation

This paper describes the development plan and design concept of the Regenerative Life Support Evaluation (RLSE) planned for flight testing in the European Space Agency Spacelab. The development plan encompasses the ongoing advanced life support subsystem and a systems integration effort to evolve concurrently subsystem concepts that perform their function and can be integrated with other subsystems in a flight demonstration of a regenerative life support system. The design concept for RLSE comprises water-electrolysis O2 generation, electrochemically depolarized CO2 removal, and Sabatier CO2 reduction for atmosphere regeneration, urine vapor-compression distillation, and wash-water hyperfiltration for waste-water recovery. The flight demonstration by RLSE is an important step in qualifying the regenerative concepts for life support in space stations.

Kleiner, G. N.↗
NASA NTRS1981

Support systems of the orbiting quarantine facility

The physical support systems, the personnel management structure, and the contingency systems necessary to permit the Orbiting Quarantine Facility (OQF) to function as an integrated system are described. The interactions between the subsystems within the preassembled modules are illustrated. The Power Module generates and distributes electrical power throughout each of the four modules, stabilizes the OQF's attitude, and dissipates heat generated throughout the system. The Habitation Module is a multifunctional structure designed to monitor and control all aspects of the system's activities. The Logistics Module stores the supplies needed for 30 days of operation and provides storage for waste materials generated during the mission. The Laboratory Module contains the equipment necessary for executing the protocol, as well as an independent life support system.

Source record↗
NASA NTRS1984

Extended mission life support systems

The life support systems employed in manned space missions have generally been based on the use of expendables, such as, for instance, liquid oxygen. For the conducted space missions, such systems have advantages related to volume, weight, and economy of power consumption. However, this situation will change in connection with Shuttle Orbiter missions of extended duration, permanent manned facilities in low-earth orbit, and ultimately manned planetary vehicles. A description is given of suitable regenerative life support systems for such extended manned space missions. Attention is given to advanced life support systems technology, air revitalization, CO2 reduction, oxygen generation, nitrogen generation, trace contaminant control, air revitalization system integration, control/monitor instrumentation, water reclamation, solid waste management, manned testing and life support integration, an enhanced duration orbiter, a space operations center, manned interplanetary life support systems, and future development requirements.

Quattrone, P. D.↗
NASA NTRS1988

Fiber optics for advanced aircraft

The increased use of composites makes the digital control more susceptible to electromagnetic effects. In order to provide the protection to the digital control additional shielding will be required as well as protective circuitry for the electronics. This results in increased weight and reduced reliability. The advantages that fiber optic technology provides for advanced aircraft applications is recognized. The use of optical signals to carry information between the aircraft and the control module provides immunity from contamination by electromagnetic sources as well as other important benefits such as reduced weight and volume resulting from the elimination of the shielding and the replacement of metal conductors with low weight glass fibers. In 1975 NASA began work to develop passive optical sensors for use with fiber optics in aircraft control systems. The problem now is to choose the best optical sensor concepts and evaluate them for use. In 1985 NASA and DOD entered into a joint program, Fiber Optic Control System Integration (FOCSI), to look at optical technology specifically for use in advanced aircraft systems. The results of this program are discussed. The conclusion of the study indicated that the use of fiber optic technology in advanced aircraft systems is feasible and desirable. The study pointed to a lack of available sensors from vendors capable of operating in the adverse environments of advanced aircraft.

Baumbick, Robert J.↗
NASA NTRS1989

A situated reasoning architecture for space-based repair and replace tasks

Space-based robots need low level control for collision detection and avoidance, short-term load management, fine-grained motion, and other physical tasks. In addition, higher level control is required to focus strategic decision making as missions are assigned and carried out. Reasoning and control must be responsive to ongoing changes in the environment. Research aimed at bridging the gap between high level artificial intelligence (AI) planning techniques and task-level robot programming for telerobotic systems is described. Situated reasoning is incorporated into AI and Robotics systems in order to coordinate a robot's activity within its environment. An integrated system under development in a component maintenance domain is described. It is geared towards replacing worn and/or failed Orbital Replacement Units (ORUs) designed for use aboard NASA's Space Station Freedom based on the collection of components available at a given time. High level control reasons in component space in order to maximize the number operational component-cells over time, while the task-level controls sensors and effectors, detects collisions, and carries out pick and place tasks in physical space. Situated reasoning is used throughout the system to cope with component failures, imperfect information, and unexpected events.

Bloom, Ben↗
NASA NTRS1989

Fiber optics for advanced aircraft

The increased use of composites makes the digital control more susceptible to electromagnetic effects. In order to provide the protection to the digital control additional shielding will be required as well as protective circuitry for the electronics. This results in increased weight and reduced reliability. The advantages that fiber optic technology provides for advanced aircraft applications is recognized. The use of optical signals to carry information between the aircraft and the control module provides immunity from contamination by electromagnetic sources as well as other important benefits such as reduced weight and volume resulting from the elimination of the shielding and the replacement of metal conductors with low weight glass fibers. In 1975 NASA began work to develop passive optical sensors for use with fiber optics in aircraft control systems. The problem now is to choose the best optical sensor concepts and evaluate them for use. In 1985 NASA and DOD entered into a joint program, Fiber Optic Control System Integration (FOCSI), to look at optical technology specifically for use in advanced aircraft systems. The results of this program are discussed. The conclusion of the study indicated that the use of fiber optic technology in advanced aircraft systems is feasible and desirable. The study pointed to a lack of available sensors from vendors capable of operating in the adverse environments of advanced aircraft.

Baumbick, Robert J.↗
NASA NTRS1993

The Solar Anomalous and Magnetospheric Particle Explorer (SAMPEX) yo-yo despin and solar array deployment mechanism

The SAMPEX spacecraft, successfully launched in July 1992, carried a yo-yo despin system and deployable solar arrays. The despin and solar array mechanisms formed an integral system as the yo-yo cables held the solar array release mechanism in place. The SAMPEX design philosophy was to minimize size and weight through the use of a predominantly single string system. The design challenge was to build a system in a limited space, which was reliable with minimal redundancy. This paper covers the design and development of the SAMPEX yo-yo despin and solar array deployment mechanisms. The problems encountered during development and testing will also be discussed.

Kellogg, James W.↗
NASA NTRS2004

NASA Glenn's Single-Stage Axial Compressor Facility Upgraded

NASA Glenn Research Center's Single-Stage Axial Compressor Facility was upgraded in fiscal year 2003 to expand and improve its research capabilities for testing high-speed fans and compressors. The old 3000-hp drive motor and gearbox were removed and replaced with a refurbished 7000-hp drive motor and gearbox, with a maximum output speed of 21,240 rpm. The higher horsepower rating permits testing of fans and compressors with higher pressure ratio or higher flow. A new inline torquemeter was installed to provide an alternate measurement of fan and compressor efficiency, along with the standard pressure and temperature measurements. A refurbished compressor bearing housing was also installed with bidirectional rotation capability, so that a variety of existing hardware could be tested. Four new lubrication modules with backup capability were installed for the motor, gearbox, torquemeter, and compressor bearing housing, so that in case the primary pump fails, the backup will prevent damage to the rotating hardware. The combustion air supply line for the facility inlet air system was activated to provide dry air for repeatable inlet conditions. New flow conditioning hardware was installed in the facility inlet plenum tank, which greatly reduced the inlet turbulence. The new inlet can also be easily modified to accommodate 20- or 22-in.-diameter fans and compressors, so a variety of existing hardware from other facilities (such as Glenn's 9- by 15-Foot Low-Speed Wind Tunnel) can be tested in the Single-Stage Axial Compressor Facility. An exhaust line was also installed to provide bleed capability to remove the inlet boundary layer. To improve the operation and control of the facility, a new programmable logic controller (PLC) was installed to upgrade from hardwired relay logic to software logic. The PLC also enabled the usage of human-machine interface software to allow for easier operation of the facility and easier reconfiguration of the facility controls when necessary. Finally, a new health-monitoring system was installed to measure shaft speed, shaft movement, and machine vibration on all of the rotating equipment. The system also provides automatic alarms and shutdown of the equipment when required. An integrated systems test for checkout of the facility was completed on June 17, 2003. Research testing resumed on June 30 with data obtained in support of the Ultra-Efficient Engine Technology Project's Compressor Casing Treatment Project.

Brokopp, Richard A.↗
NASA NTRS2007

NASA Space Flight Human System Standards

NASA has begun a new approach to human factors design standards. For years NASA-STD-3000, Manned Systems Integration Standards, has been a source of human factors design guidance for space systems. In order to better meet the needs of the system developers, NASA is revising its human factors standards system. NASA-STD-3000 will be replaced by two documents: set of broad human systems specifications (including both human factors and medical topics) and a human factors design handbook

Tillman, Barry↗
NASA NTRS2007

Architecting the Communication and Navigation Networks for NASA's Space Exploration Systems

NASA is planning a series of short and long duration human and robotic missions to explore the Moon and then Mars. A key objective of the missions is to grow, through a series of launches, a system of systems communication, navigation, and timing infrastructure at minimum cost while providing a network-centric infrastructure that maximizes the exploration capabilities and science return. There is a strong need to use architecting processes in the mission pre-formulation stage to describe the systems, interfaces, and interoperability needed to implement multiple space communication systems that are deployed over time, yet support interoperability with each deployment phase and with 20 years of legacy systems. In this paper we present a process for defining the architecture of the communications, navigation, and networks needed to support future space explorers with the best adaptable and evolable network-centric space exploration infrastructure. The process steps presented are: 1) Architecture decomposition, 2) Defining mission systems and their interfaces, 3) Developing the communication, navigation, networking architecture, and 4) Integrating systems, operational and technical views and viewpoints. We demonstrate the process through the architecture development of the communication network for upcoming NASA space exploration missions.

Bhassin, Kul B.↗
NASA NTRS2008

Human Factors Engineering Standards at NASA

NASA has begun a new approach to human factors design standards. For years NASA-STD-3000, Manned Systems Integration Standards, has been a source of human factors design guidance for space systems. In order to better meet the needs of the system developers, NASA is revising its human factors standards system. NASA-STD-3000 will be replaced by two documents: set of broad human systems design standards (including both human factors and medical topics) and a human factors design handbook. At the present time the standards document is in final review with some disagreement on several critical issues. The handbook is progressing with November 2008 as the anticipated completion date.

Russo, Dane↗
NASA NTRS2011

Systems Analysis Approach for the NASA Environmentally Responsible Aviation Project

This conference paper describes the current systems analysis approach being implemented for the Environmentally Responsible Aviation Project within the Integrated Systems Research Program under the NASA Aeronautics Research Mission Directorate. The scope and purpose of these systems studies are introduced followed by a methodology overview. The approach involves both top-down and bottoms-up components to provide NASA s stakeholders with a rationale for the prioritization and tracking of a portfolio of technologies which enable the future fleet of aircraft to operate with a simultaneous reduction of aviation noise, emissions and fuel-burn impacts to our environment. Examples of key current results and relevant decision support conclusions are presented along with a forecast of the planned analyses to follow.

Kimmel, William M.↗
NASA NTRS2007

Global Environmental Micro Sensors Test Operations in the Natural Environment

ENSCO, Inc. is developing an innovative atmospheric observing system known as Global Environmental Micro Sensors (GEMS). The GEMS concept features an integrated system of miniaturized in situ, airborne probes measuring temperature, relative humidity, pressure, and vector wind velocity. In order for the probes to remain airborne for long periods of time, their design is based on a helium-filled super-pressure balloon. The GEMS probes are neutrally buoyant and carried passively by the wind at predetermined levels. Each probe contains onboard satellite communication, power generation, processing, and geolocation capabilities. ENSCO has partnered with the National Aeronautics and Space Administration's Kennedy Space Center (KSC) for a project called GEMS Test Operations in the Natural Environment (GEMSTONE) that will culminate with limited prototype flights of the system in spring 2007. By leveraging current advances in micro and nanotechnology, the probe mass, size, cost, and complexity can be reduced substantially so that large numbers of probes could be deployed routinely to support ground, launch, and landing operations at KSC and other locations. A full-scale system will improve the data density for the local initialization of high-resolution numerical weather prediction systems by at least an order of magnitude and provide a significantly expanded in situ data base to evaluate launch commit criteria and flight rules. When applied to launch or landing sites, this capability will reduce both weather hazards and weather-related scrubs, thus enhancing both safety and cost-avoidance for vehicles processed by the Shuttle, Launch Services Program, and Constellation Directorates. The GEMSTONE project will conclude with a field experiment in which 10 to 15 probes are released over KSC in east central Florida. The probes will be neutrally buoyant at different altitudes from 500 to 3000 meters and will report their position, speed, heading, temperature, humidity, and pressure via satellite. The GEMS data will be validated against reference observations provided by current weather instrumentation located at KSC. This paper will report on the results of the GEMSTONE project and discuss the challenges encountered in developing an airborne sensor system.

Adams, Mark L.↗
NASA NTRS1988

A Design Study of Onboard Navigation and Guidance During Aerocapture at Mars

The navigation and guidance of a high lift-to-drag ratio sample return vehicle during aerocapture at Mars are investigated. Emphasis is placed on integrated systems design, with guidance algorithm synthesis and analysis based on vehicle state and atmospheric density uncertainty estimates provided by the navigation system. The latter utilizes a Kalman filter for state vector estimation, with useful update information obtained through radar altimeter measurements and density altitude measurements based on IMU-measured drag acceleration. A three-phase guidance algorithm, featuring constant bank numeric predictor/corrector atmospheric capture and exit phases and an extended constant altitude cruise phase, is developed to provide controlled capture and depletion of orbital energy, orbital plane control, and exit apoapsis control. Integrated navigation and guidance systems performance are analyzed using a four degree-of-freedom computer simulation. The simulation environment includes an atmospheric density model with spatially correlated perturbations to provide realistic variations over the vehicle trajectory. Navigation filter initial conditions for the analysis are based on planetary approach optical navigation results. Results from a selection of test cases are presented to give insight into systems performance.

Fuhry, Douglas Paul↗
DOE OSTI2023

ARIES/Flatirons Facility - Hydrogen System Capability Buildout

Under the "Advanced Research on Integrated Energy Systems" (ARIES) initiative, hydrogen system capabilities including a MW-scale electrolyzer, storage system, and MW-scale fuel cell generator will be designed and commissioned at NREL's Flatirons Campus. This hydrogen infrastructure will support H2@Scale goals by enabling integrated systems R&D to study the science of scaling for hydrogen energy systems.The system is designed with flexibility to provide a testbed to demonstrate systems integration, grid services, energy storage, direct renewable hydrogen production, and innovative end use applications (e.g. HD transportation, natural gas blending, etc.).

Advanced Research on Integrated Energy Systems↗