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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 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
NASA NTRS1999

Effect of Space Flight on Adrenal Medullary Function

We hypothesize that microgravity conditions during space flight alter the expression and specific activities of the adrenal medullary CA synthesizing enzymes (CASE). Previously, we examined adrenals from six rats flown for six days aboard STS 54 and reported that microgravity induced a decrease in the expression and specific activity of rat adrenal medullary tyrosine hydroxylase, the rate limiting enzyme of CA synthesis, without affecting the expression of other CASE. In the past, we analyzed some of the > 300 adrenals from two previous Space Shuttle missions (PARE 03 and SLS 2). The preliminary results (a) attest to the good state of tissue preservation, thus proving the feasibility of subsequent large-scale evaluation, and (b) confirm and extend our previous findings. With this grant we will be able to expeditiously analyze all our specimens and to complete our studies in a timely fashion.

Lelkes, Peter I.↗
NASA NTRS2006

Suited for Space

This viewgraph presentation describes the basic functions of space suits for EVA astronauts. Space suits are also described from the past, present and future space missions. The contents include: 1) Why Do You Need A Space Suit?; 2) Generic EVA System Requirements; 3) Apollo Lunar Surface Cycling Certification; 4) EVA Operating Cycles for Mars Surface Missions; 5) Mars Surface EVA Mission Cycle Requirements; 6) Robustness Durability Requirements Comparison; 7) Carry-Weight Capabilities; 8) EVA System Challenges (Mars); 9) Human Planetary Surface Exploration Experience; 10) NASA Johnson Space Center Planetary Analog Activities; 11) Why Perform Remote Field Tests; and 12) Other Reasons Why We Perform Remote Field Tests.

Kosmo, Joseph J.↗
NASA NTRS2009

Space Flight and Manual Control: Implications for Sensorimotor Function on Future Missions

Control of vehicles, and other complex mechanical motion systems, is a high-level integrative function of the central nervous system (CNS) that requires good visual acuity, eye-hand coordination, spatial (and, in some cases, geographic) orientation perception, and cognitive function. Existing evidence from space flight research (Paloski et.al., 2008, Clement and Reschke 2008, Reschke et al., 2007) demonstrates that the function of each of these systems is altered by removing (and subsequently by reintroducing) a gravitational field that can be sensed by vestibular, proprioceptive, and haptic receptors and used by the CNS for spatial orientation, navigation, and coordination of movements. Furthermore, much of the operational performance data collected as a function of space flight has not been available for independent analysis, and those data that have been reviewed are equivocal owing to uncontrolled environmental and/or engineering factors. Thus, our current understanding, when it comes to manual control, is limited primarily to a review of those situations where manual control has been a factor. One of the simplest approaches to the manual control problem is to review shuttle landing data. See the Figure below for those landing for which we have Shuttle velocities over the runway threshold.

Reschke, Millard F.↗
NASA NTRS1974

Derivation of formulas for root-mean-square errors in location, orientation, and shape in triangulation solution of an elongated object in space

Formulas are derived for the root-mean-square (rms) displacement, slope, and curvature errors in an azimuth-elevation image trace of an elongated object in space, as functions of the number and spacing of the input data points and the rms elevation error in the individual input data points from a single observation station. Also, formulas are derived for the total rms displacement, slope, and curvature error vectors in the triangulation solution of an elongated object in space due to the rms displacement, slope, and curvature errors, respectively, in the azimuth-elevation image traces from different observation stations. The total rms displacement, slope, and curvature error vectors provide useful measure numbers for determining the relative merits of two or more different triangulation procedures applicable to elongated objects in space.

Long, S. A. T.↗
NASA NTRS2013

Biomedical Results of the Space Shuttle Program

The Space Shuttle Program (SSP), which was triumphantly completed by the flight of STS-135 on July 21, 2011, holds a special place in the history of Human Space Exploration. For the first time, a vehicle was built that could perform multiple flights in space and return to Earth. Many important questions regarding the ability of humans to adapt and function in space have been answered during the 30 years since the SSP was launched and many lessons have been learned. The multidisciplinary studies conducted during this program allowed NASA to define the normal responses and potential pathologic changes of the major physiological systems to short-duration space flights. The program significantly contributed to the development of in-flight medical care capabilities and multiple countermeasures. A comprehensive system of preflight, in-flight, and post-flight monitoring of the astronauts was built. It is important to emphasize that the SSP was essential for building the International Space Station (ISS) that significantly expanded the boundaries of space research, allowing for planning of long-term near-terrestrial and extraterrestrial missions. As the program was coming to completion, a decision was made by the NASA Lyndon B. Johnson Space Center Human Research Program senior management to summarize the medico-biological results of the SSP in one comprehensive edition. This was quite an ambitious goal. It required selection of a group of experts in different areas to become the chapters lead authors. These experts were charged with the task of reviewing what was learned in the consequent fields to make the chapters a comprehensive source of information for planning of research, operational activities, and medical care for future missions. We hope that we were able to accomplish this goal and the book will serve as a reliable reference edition for the international space biomedicine community, for new generation of space researchers and Flight Surgeons, as well as for all those interested in space exploration. As space exploration continues, the major question of whether humans are capable of adapting to long-term presence and adequately functioning in space habitats will remain open for a long time. we expect that the comprehensive review of the medico-biological results of the SSP along with the data collected during the missions on the space stations (the Russian space station _Mir_ and ISS) provides a good starting point in seeking the answer to this question.

Diana Risin↗
NASA NTRS2004

Image-Based Computational Fluid Dynamics in Blood Vessel Models: Toward Developing a Prognostic Tool to Assess Cardiovascular Function Changes in Prolonged Space Flights

One of NASA's objectives is to be able to perform a complete, pre-flight, evaluation of cardiovascular changes in astronauts scheduled for prolonged space missions. Computational fluid dynamics (CFD) has shown promise as a method for estimating cardiovascular function during reduced gravity conditions. For this purpose, MRI can provide geometrical information, to reconstruct vessel geometries, and measure all spatial velocity components, providing location specific boundary conditions. The objective of this study was to investigate the reliability of MRI-based model reconstruction and measured boundary conditions for CFD simulations. An aortic arch model and a carotid bifurcation model were scanned in a 1.5T Siemens MRI scanner. Axial MRI acquisitions provided images for geometry reconstruction (slice thickness 3 and 5 mm; pixel size 1x1 and 0.5x0.5 square millimeters). Velocity acquisitions provided measured inlet boundary conditions and localized three-directional steady-flow velocity data (0.7-3.0 L/min). The vessel walls were isolated using NIH provided software (ImageJ) and lofted to form the geometric surface. Constructed and idealized geometries were imported into a commercial CFD code for meshing and simulation. Contour and vector plots of the velocity showed identical features between the MRI velocity data, the MRI-based CFD data, and the idealized-geometry CFD data, with less than 10% differences in the local velocity values. CFD results on models reconstructed from different MRI resolution settings showed insignificant differences (less than 5%). This study illustrated, quantitatively, that reliable CFD simulations can be performed with MRI reconstructed models and gives evidence that a future, subject-specific, computational evaluation of the cardiovascular system alteration during space travel is feasible.

Chatzimavroudis, George P.↗
NASA NTRSDate not supplied

Long-Term Corrosivity at NASA Kennedy Space Center as a Function of Distance and Time from the Atlantic Ocean

Long-term data to record both seasonal and notional bounding values for corrosivity at multiple sites at NASA Kennedy Space Center was needed to make better materials choices for NASA-based ground and spaceflight programs. The data was valuable for two key reasons, 1) to measure corrosion rate and chloride concentration as a function of time and distance from the Atlantic Ocean, and 2) compare the corrosivity at launchpad and site-specific areas to the more accelerated conditions at the KSC Beachside Atmospheric Corrosion Test Site for coating and materials performance prediction. Sites were chosen from 45 meter (150 feet) to 8 kilometers (5 miles) from the Atlantic Ocean and corrosion variables at each site were measured throughout each year from June 2017 to April 2023, except the Beachside site, which includes data from November 2010. The summary includes corrosivity data and coating performance comparisons at select sites, which will be used as the updated NASA corrosivity standard for corrosion control requirements.

NASA↗
NASA NTRS2014

Controllable Multi-Functional Heat Exchanger for Space Applications

Team Spacering will design SpaceRing, a cooling and waste heat recycling system that addresses NASA’s interest for a cooling and power-generating unit in its prototype deep space habitat[1]. The merits of this system are as follows: - Controllable cooling is critical in maintaining a habitable environment and in the functionality of life support systems, powering electronics and other devices in a spacecraft. - Power is expensive to produce in a space environment. Converting wasted thermal energy into electricity will save energy and money for the space station. Space habitation is a highly complex endeavor. Consequently, the SpaceRing must adhere to additional constraints, which include: - Lack of natural fluid or gas convection due to micro-gravity environment - Limited range for heat source and cold sink temperature - Subject to high fluctuations of incoming thermal energy - Minimal weight due to the high cost of transporting items into space After consulting with NASA and experts in thermal studies, several design objectives were identified and are listed below in order of importance: - High cooling capacity - Reliable safety control and alert system - Maximization of energy generation from wasted heat - Optimization of cooling capability and power generation - Long operational life and minimization of maintenance In space, conventional cooling systems utilize passive heat pipe systems for small-scale heat rejection and pumped pipes with heat exchangers for large-scale heat rejection. Thermal power generation in space is mainly achieved by using thermoelectric material that produces electric energy from temperature differentials. We propose a design that combines cooling and thermoelectric power generation. Using a hot pipe connected to a heat source, a cold pipe connected to a radiator, a heat exchanger in contact with both pipes, and a pump in each pipe to move the fluid, we make an active cooling system. The thermoelectric material is inserted in the heat exchanger between the hot and cold pipes to extract energy from the maximum temperature difference coming from the two pipes. It also provides controllable cooling capacity through the use of the thermoelectric material as cooling modules. We have tested our system under target heat source and sink conditions and measured the temperatures and flow rates. Our preliminary results are promising, demonstrating the output of 25 Watts of power on average. We are in the process of running control tests to compare the heat transfer performance without the thermoelectric generators, which is vital in determining whether or not the generators introduce an unacceptable amount of thermal resistance. While some control tests have been run already, the results have been noisy. We have modified our testing environment and data acquisition methods to allow for simple comparison between the control test results and thermoelectric performance results. Lastly, we have modified the heat exchanger design slightly to include acrylic baffles. This will allow the heat to flow through the heat exchanger more efficiently. We have presented our preliminary results to NASA and will deliver the final product by the end of May 2014.

Lee Xiong↗
NASA NTRS1974

Space shuttle configuration accounting functional design specification

An analysis is presented of the requirements for an on-line automated system which must be capable of tracking the status of requirements and engineering changes and of providing accurate and timely records. The functional design specification provides the definition, description, and character length of the required data elements and the interrelationship of data elements to adequately track, display, and report the status of active configuration changes. As changes to the space shuttle program levels II and III configuration are proposed, evaluated, and dispositioned, it is the function of the configuration management office to maintain records regarding changes to the baseline and to track and report the status of those changes. The configuration accounting system will consist of a combination of computers, computer terminals, software, and procedures, all of which are designed to store, retrieve, display, and process information required to track proposed and proved engineering changes to maintain baseline documentation of the space shuttle program levels II and III.

Source record↗
NASA NTRS1972

Probability of satellite collision

A method is presented for computing the probability of a collision between a particular artificial earth satellite and any one of the total population of earth satellites. The collision hazard incurred by the proposed modular Space Station is assessed using the technique presented. The results of a parametric study to determine what type of satellite orbits produce the greatest contribution to the total collision probability are presented. Collision probability for the Space Station is given as a function of Space Station altitude and inclination. Collision probability was also parameterized over miss distance and mission duration.

Mccarter, J. W.↗
NASA NTRS1973

Remotely Manned Systems for operation and exploration in space

A brief overview is presented of Remotely Manned Systems with emphasis on their use as tools for exploration and operation in space. Remotely Manned Systems missions and functions in space are described and classified in relation to other existing or planned space systems. Problem areas of large-scale man-machine systems are identified based on experience in the Surveyor program, the Mariner 9 Mars orbiter project and the Apollo program. The effects of communication time delay on system performance are investigated using the average velocity of a Martian rover as performance indicator. A substantial performance increase can be achieved by providing certain autonomous capabilities to the remote system.

Heer, E.↗
NASA NTRS1972

Advanced Software Techniques for Data Management Systems. Volume 2: Space Shuttle Flight Executive System: Functional Design

A functional design of software executive system for the space shuttle avionics computer is presented. Three primary functions of the executive are emphasized in the design: task management, I/O management, and configuration management. The executive system organization is based on the applications software and configuration requirements established during the Phase B definition of the Space Shuttle program. Although the primary features of the executive system architecture were derived from Phase B requirements, it was specified for implementation with the IBM 4 Pi EP aerospace computer and is expected to be incorporated into a breadboard data management computer system at NASA Manned Spacecraft Center's Information system division. The executive system was structured for internal operation on the IBM 4 Pi EP system with its external configuration and applications software assumed to the characteristic of the centralized quad-redundant avionics systems defined in Phase B.

Pepe, J. T.↗
NASA NTRS1986

Analysis of crew functions as an aid in Space Station interior layout

The Space Station must be designed to facilitate all of the functions that its crew will perform, both on-duty and off-duty, as efficiently and comfortably as possible. This paper examines the functions to be performed by the Space Station crew in order to make inferences about the design of an interior layout that optimizes crew productivity. Twenty-seven crew functions were defined, as well as five criteria for assessing relationships among all pairs of those functions. Hierarchical clustering and multidimensional scaling techniques were used to visually summarize the relationships. A key result was the identification of two dimensions for describing the configuration of crew functions: 'Private-Public' and 'Group-Individual'. Seven specific recommendations for Space Station interior layout were derived from the analyses.

Steinberg, A. L.↗