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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 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS1989

Space station wardroom habitability and equipment study

Experimental designs in life-size mock-up form for the wardroom facility for the Space Station Habitability Module are explored and developed. In Phase 1, three preliminary concepts for the wardroom configuration are fabricated and evaluated. In Phase 2, the results of Phase 1 are combined with a specific range of program design requirements to provide the design criteria for the fabrication of an innovative medium-fidelity mock-up of a wardrobe configuration. The study also focuses on the design and preliminary prototyping of selected equipment items including crew exercise compartments, a meal/meeting table and a portable workstation. Design criteria and requirements are discussed and documented. Preliminary and final mock-ups and equipment prototypes are described and illustrated.

Nixon, David↗
NASA NTRS1978

Solar heating and cooling system design and development

Application surveys and performance studies were conducted to determine a solar heating and hot water configuration that could be used in a variety of applications, and to identify subsystem modules that could be utilized in a building block fashion to adapt hardware items to single and multi-family residential and commercial systems. Topics discussed include: subsystem development for the solar collectors, controls, other components, energy management module, and the heating system configuration test. Operational tests conducted at an Illinois farmhouse, and a YWCA in Spokane, Washington are discussed.

Source record↗
NASA NTRS2011

Helium-Cooled Black Shroud for Subscale Cryogenic Testing

This shroud provides a deep-space simulating environment for testing scaled-down models of passively cooling systems for spaceflight optics and instruments. It is used inside a liquid-nitrogen- cooled vacuum chamber, and it is cooled by liquid helium to 5 K. It has an inside geometry of approximately 1.6 m diameter by 0.45 m tall. The inside surfaces of its top and sidewalls have a thermal absorptivity greater than 0.96. The bottom wall has a large central opening that is easily customized to allow a specific test item to extend through it. This enables testing of scale models of realistic passive cooling configurations that feature a very large temperature drop between the deepspace-facing cooled side and the Sun/Earth-facing warm side. This shroud has an innovative thermal closeout of the bottom wall, so that a test sample can have a hot (room temperature) side outside of the shroud, and a cold side inside the shroud. The combination of this closeout and the very black walls keeps radiated heat from the sample s warm end from entering the shroud, reflecting off the walls and heating the sample s cold end. The shroud includes 12 vertical rectangular sheet-copper side panels that are oriented in a circular pattern. Using tabs bent off from their edges, these side panels are bolted to each other and to a steel support ring on which they rest. The removable shroud top is a large copper sheet that rests on, and is bolted to, the support ring when the shroud is closed. The support ring stands on four fiberglass tube legs, which isolate it thermally from the vacuum chamber bottom. The insides of the cooper top and side panels are completely covered with 25- mm-thick aluminum honeycomb panels. This honeycomb is painted black before it is epoxied to the copper surfaces. A spiral-shaped copper tube, clamped at many different locations to the outside of the top copper plate, serves as part of the liquid helium cooling loop. Another copper tube, plumbed in a series to the top plate s tube, is clamped to the sidewall tabs where they are bolted to the support ring. Flowing liquid helium through these tubes cools the entire shroud to 5 K. The entire shroud is wrapped loosely in a layer of double-aluminized Kapton. The support ring s inner diameter is the largest possible hole through which the test item can extend into the shroud. Twelve custom-sized trapezoidal copper sheets extend inward from the support ring to within a few millimeters of the test item. Attached to the inner edge of each of these sheets is a custom-shaped strip of Kapton, which is aluminum- coated on the warm-facing (outer) side, and has thin Dacron netting attached to its cold-facing side. This Kapton rests against the test item, but the Dacron keeps it from making significant thermal contact. The result is a non-contact, radiatively reflective thermal closeout with essentially no gap through which radiation can pass. In this way, the part of the test item outside the shroud can be heated to relatively high temperatures without any radiative heat leaking to the inside.

Tuttle, James↗
NASA NTRS1999

Product Structure, the Heart of Product Definition

This paper describes the LMMSS Product Definition System (PDS) philosophy and approach were the use of each item parts document or software can be traced to a specific end item (EI) serial/tail number of the product. It explains why a part-oriented approach to data organization and configuration management is required. The definition of part-oriented is that all appropriate product definition data products will be collected. Referenced and managed by their linkage/relationship to parts/items, The paper will touch upon how LMMSS store/controls product definition information under each project's top product designator in a two tiered approach. One tier for each product end item and another tier which contain/controls listings of drawings, documents. Specifications and standards that are required for hardware item definition.

DeHoog, C., Jr.↗
NASA NTRS1974

Solar array study for solar electric propulsion spacecraft for the Encke rendezvous mission

The work is described which was performed on the design, analysis and performance of a 20 kW rollup solar array capable of meeting the design requirements of a solar electric spacecraft for the 1980 Encke rendezvous mission. To meet the high power requirements of the proposed electric propulsion mission, solar arrays on the order of 186.6 sq m were defined. Because of the large weights involved with arrays of this size, consideration of array configurations is limited to lightweight, large area concepts with maximum power-to-weight ratios. Items covered include solar array requirements and constraints, array concept selection and rationale, structural and electrical design considerations, and reliability considerations.

Sequeira, E. A.↗
NASA NTRS1985

Commonality analysis for the NASA Space Station Common Module

The concept of commonality to enhance cost savings, as applied to NASA's Space Station Common Module (CM), is explored. The equipment to be included in the CM is organized by subsystems of structure, power, thermal, command and data handling, environmental control and life support, and crew station. The weight, volume, and quantity of each instrument item will be subsequently added to support a cost model. The CM concept, its reference configuration, power distribution and management, and cost sensitivity options are discussed in detail. Some computer programs are outlined, stressing the importance of the existing capabilities of the STS and the optimum commonality case.

Powell, L. E.↗
NASA NTRS1995

Program For Analyzing Failures In A Complex System

Configurable Real-Time Analysis System (CRANS) computer program provides means for representing logically interconnected items (e.g., modules of equipment in complicated system) in matrix format. Capabilities provided helpful in real-time environment (e.g., operational environment of such system), in which need for quick evaluation of results of changes or failures. Program facilitates rapid logic-tree analysis. Written in C language.

Mccluney, R. Kevin↗
NASA NTRS1996

ATTDES: An Expert System for Satellite Attitude Determination and Control

The design, analysis, and flight operations of satellite attitude determintion and attitude control systems require extensive mathematical formulations, optimization studies, and computer simulation. This is best done by an analyst with extensive education and experience. The development of programs such as ATTDES permit the use of advanced techniques by those with less experience. Typical tasks include the mission analysis to select stabilization and damping schemes, attitude determination sensors and algorithms, and control system designs to meet program requirements. ATTDES is a system that includes all of these activities, including high fidelity orbit environment models that can be used for preliminary analysis, parameter selection, stabilization schemes, the development of estimators covariance analyses, and optimization, and can support ongoing orbit activities. The modification of existing simulations to model new configurations for these purposes can be an expensive, time consuming activity that becomes a pacing item in the development and operation of such new systems. The use of an integrated tool such as ATTDES significantly reduces the effort and time required for these tasks.

Mackison, Donald L.↗
NASA NTRS2012

Requirements, Resource Planning and Management for Decrewing/Recrewing Scenarios of the International Space Station

Following the failure of 44P on launch in August 2011, and the subsequent grounding of all Russian Soyuz rocket based launches, the ISS ground teams engaged in an effort to determine how long the ISS could remain crewed, what would be required to safely configure the ISS for decrewing, and what would be required to recrew the ISS upon resumption of Soyuz rocket launches if decrewing became necessary. This White Paper was written to capture the processes and lessons learned from real-time time events and to provide a reference and training document for ISS Program teams in the event decrewing of the ISS is needed. Through coordination meetings and assessments, teams identified six decrewing priorities for ground and crew operations. These priorities were integrated along with preflight priorities through the Increment replanning process. Additionally, the teams reviewed, updated, and implemented changes to the governing documentation for the configuration of the ISS for a contingency decrewing event. Steps were taken to identify critical items for disposal prior to decrewing, as well as identifying the required items to be strategically staged or flown with the astronauts and cosmonauts who would eventually recrew the ISS. After the successful launches and dockings of both 45P and 28S, the decrewing team transitioned to finalizing and publishing the documentation for standardizing the decrewing flight rules. With the continued launching of crews and cargo to the ISS, utilization and science is again a high priority, with the Increment pairs 29 and 30, and 31 and 32 reaching the milestone of at least 35 hours per week average utilization.

Bach, David A.↗
NASA NTRS2013

Requirements, Resource Planning, and Management for Decrewing/Recrewing Scenarios of the International Space Station

Following the failure of 44 Progress (44P) on launch in August 2011, and the subsequent grounding of all Russian Soyuz rocket based launches, the International Space Station (ISS) ground teams engaged in an effort to determine how long the ISS could remain crewed, what would be required to safely configure the ISS for decrewing, and what would be required to recrew the ISS upon resumption of Soyuz rocket launches if decrewing became necessary. This White Paper was written to capture the processes and lessons learned from real-time time events and to provide a reference and training document for ISS Program teams in the event decrewing of the ISS is needed. Through coordination meetings and assessments, teams identified six decrewing priorities for ground and crew operations. These priorities were integrated along with preflight priorities through the Increment re-planning process. Additionally, the teams reviewed, updated, and implemented changes to the governing documentation for the configuration of the ISS for a contingency decrewing event. Steps were taken to identify critical items for disposal prior to decrewing, as well as identifying the required items to be strategically staged or flown with the astronauts and cosmonauts who would eventually recrew the ISS. After the successful launches and dockings of both 45P and 28 Soyuz (28S), the decrewing team transitioned to finalizing and publishing the documentation for standardizing the decrewing flight rules. With the continued launching of crews and cargo to the ISS, utilization and science is again a high priority; both Increment pairs 29 and 30, and Increment 31 and 32 reaching the milestone of at least 35 hours per week average utilization.

Bach, David A.↗
NASA NTRS1987

Aerodynamic characteristics of the modified 40- by 80-foot wind tunnel as measured in a 1/50th-scale model

The aerodynamic characteristics of the 40- by 80-Foot Wind Tunnel at Ames Research Center were measured by using a 1/50th-scale facility. The model was configured to closely simulate the features of the full-scale facility when it became operational in 1986. The items measured include the aerodynamic effects due to changes in the total-pressure-loss characteristics of the intake and exhaust openings of the air-exchange system, total-pressure distributions in the flow field at locations around the wind tunnel circuit, the locations of the maximum total-pressure contours, and the aerodynamic changes caused by the installation of the acoustic barrier in the southwest corner of the wind tunnel. The model tests reveal the changes in the aerodynamic performance of the 1986 version of the 40- by 80-Foot Wind Tunnel compared with the performance of the 1982 configuration.

Smith, Brian E.↗
NASA NTRS1972

Life sciences payload definition and integration study. Volume 3: Appendices

Detail design information concerning payloads for biomedical research projects conducted during space missions is presented. Subjects discussed are: (1) equipment modules and equipment item lists, (2) weight and volume breakdown by payload and equipment units, (3) longitudinal floor arrangement configuration, and (4) nonbaseline second generation layouts.

Source record↗
NASA NTRS1993

Space Station maintenance studies using plaid graphics

The Graphics Analysis Facility (GRAF) has been used frequently to study extravehicular activity (EVA) maintenance scenarios on Space Station Freedom. The ability to use 3-dimensional visualization gives one a more accurate estimate of the Space Station environment. Moreover, human EVA and robotic kinematics can be accurately simulated for columetric reach and collision detection analysis. An animation of this kind was developed for a research group at JSC to study and discover problem areas involved with doing external Space Station maintenance tasks. On the EVA side, it was discovered that items such as handholds and temporary restraint mechanisms should more effectively facilitate EVA movement about the Space Station structure for the suited personnel. Issues concerning CETA cart configuration, PWP storage locations, and locations of EVA storage areas were also identified by use of the animation. In the area of EVA versus robotics, it was found that there is a strong desire to make EVA and robotics interfaces compatible on items such as replacement units and unpressurized logistics carriers. The animation also showed that the use of robotics within an EVA task increases the difficulty and duration of the task setup, leaving less time available for the maintenance task itself. Graphics animation provides a mechanism to simultaneously analyze several mission parameters (i.e., EVA reach, volumetric analysis, and task timelines), and thus, it has proven to be an effective method for mission evaluation.

Helm, Mary E.↗
NASA NTRS1994

Universal signal conditioning amplifier

A state-of-the-art instrumentation amplifier capable of being used with most types of transducers has been developed at the Kennedy Space Center. This Universal Signal Conditioning Amplifier (USCA) can eliminate costly measurement setup item and troubleshooting, improve system reliability and provide more accurate data than conventional amplifiers. The USCA can configure itself for maximum resolution and accuracy based on information read from a RAM chip attached to each transducer. Excitation voltages or current are also automatically configured. The amplifier uses both analog and digital state-of-the-art technology with analog-to-digital conversion performed in the early stages in order to minimize errors introduced by offset and gain drifts in the analog components. A dynamic temperature compensation scheme has been designed to achieve and maintain 12-bit accuracy of the amplifier from 0 to 70 C. The digital signal processing section allows the implementation of digital filters up to 511th order. The amplifier can also perform real-time linearizations up to fourth order while processing data at a rate of 23.438 kS/s. Both digital and analog outputs are available from the amplifier.

Medelius, Pedro J.↗
NASA NTRS1971

Space Shuttle: Static pressure distribution on Chrysler Corporation Space Division SERV booster configuration

A dual purpose test was conducted in the propulsion wind tunnel (PWT) to evaluate the performance of an aerospike engine, in the presence of a booster, and obtain forebody and base pressure distributions on the booster in which it is installed. The test item was a 2.5 percent scaled replica of the SERV booster employing a 5 percent spike length aerospike engine installed in the base region of the model. Cold flow air was used to simulate engine jet operation. Two booster configurations were investigated, one on which reentry aerospike engine thermal protection doors were installed, and another where the doors were removed. The data presented are representative of the latter configuration for a Mach number range of 0 to 1.25 at angles of attack of 0 and 8 degrees and 0 degrees angle of sideslip.

Price, E. A.↗
NASA NTRS1977

Space-based solar power conversion and delivery systems study. Volume 5: Economic analysis

Space-based solar power conversion and delivery systems are studied along with a variety of economic and programmatic issues relevant to their development and deployment. The costs, uncertainties and risks associated with the current photovoltaic Satellite Solar Power System (SSPS) configuration, and issues affecting the development of an economically viable SSPS development program are addressed. In particular, the desirability of low earth orbit (LEO) and geosynchronous (GEO) test satellites is examined and critical technology areas are identified. The development of SSPS unit production (nth item), and operation and maintenance cost models suitable for incorporation into a risk assessment (Monte Carlo) model (RAM) are reported. The RAM was then used to evaluate the current SSPS configuration expected costs and cost-risk associated with this configuration. By examining differential costs and cost-risk as a function of postulated technology developments, the critical technologies, that is, those which drive costs and/or cost-risk, are identified. It is shown that the key technology area deals with productivity in space, that is, the ability to fabricate and assemble large structures in space, not, as might be expected, with some hardware component technology.

Source record↗
NASA NTRS1986

Evaluation of diffuse-illumination holographic cinematography in a flutter cascade

Since 1979, the Lewis Research Center has examined holographic cinematography for three-dimensional flow visualization. The Nd:YAG lasers used were Q-switched, double-pulsed, and frequency-doubled, operating at 20 pulses per second. The primary subjects for flow visualization were the shock waves produced in two flutter cascades. Flow visualization was by diffuse-illumination, double-exposure, and holographic interferometry. The performances of the lasers, holography, and diffuse-illumination interferometry are evaluated in single-window wind tunnels. The fringe-contrast factor is used to evaluate the results. The effects of turbulence on shock-wave visualization in a transonic flow are discussed. The depth of field for visualization of a turbulent structure is demonstrated to be a measure of the relative density and scale of that structure. Other items discussed are the holographic emulsion, tests of coherence and polarization, effects of windows and diffusers, hologram bleaching, laser configurations, influence and handling of specular reflections, modes of fringe localization, noise sources, and coherence requirements as a function of the pulse energy. Holography and diffuse illumination interferometry are also reviewed.

Decker, A. J.↗
NASA NTRS1993

Distributed Virtual System (DIVIRS) Project

As outlined in our continuation proposal 92-ISI-50R (revised) on contract NCC 2-539, we are (1) developing software, including a system manager and a job manager, that will manage available resources and that will enable programmers to program parallel applications in terms of a virtual configuration of processors, hiding the mapping to physical nodes; (2) developing communications routines that support the abstractions implemented in item one; (3) continuing the development of file and information systems based on the virtual system model; and (4) incorporating appropriate security measures to allow the mechanisms developed in items 1 through 3 to be used on an open network. The goal throughout our work is to provide a uniform model that can be applied to both parallel and distributed systems. We believe that multiprocessor systems should exist in the context of distributed systems, allowing them to be more easily shared by those that need them. Our work provides the mechanisms through which nodes on multiprocessors are allocated to jobs running within the distributed system and the mechanisms through which files needed by those jobs can be located and accessed.

Schorr, Herbert↗