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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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The problems in human comfort in heat stress are emphasized, with less emphasis placed upon cold exposure problems. Physiological parameters related to human thermal interactions are discussed, as well as data concerning thermal protective clothing. The energy balance equation, heat transfer equation, thermal comfort, heat stress, and cold stress are also considered. A two node model of human temperature regulation in FORTRAN is appended.
Results of a requirements analysis task for Integrated Programs for Aerospace Vehicle Design (IPAD) are presented. User requirements which, in part, will shape the IPAD system design are given. Requirements considered were: generation, modification, storage, retrieval, communication, reporting, and protection of information. Data manipulation and controls on the system and the information were also considered. Specific needs relative to the product design process are also discussed.
The exobiology program investigates the planetary events which were responsible for, or, related to, the origin, evolution, and distribution of life in the universe. The areas involved include: chemical evolution, organic geochemistry, origin and evolution of life, planetary environments, life in the universe, planetary protection, and Mars data analysis.
Five volunteer subjects were tested for acceleration tolerance under eight different experimental conditions representing relaxed and unprotected tolerance and tolerance with all possible combinations of the anti-G suit, and M-1 maneuver, and supination in a PALE seat. The individual and combined effects of the various acceleration protective techniques were examined as they related to various models for acceleration protection, and the data revealed no statistically significant deviations from a simple additive model. The apparent net additivity was interpreted as resulting from a combination of additive, synergistic, and overlapping mechanisms.
A multicomputer is defined as a set of tightly-coupled yet autonomous computers capable of synchronizing and communicating in parallel but also of operating independently. The architectural concepts and requirements for executing the Ada programs in a multicomputer system are discussed. Synchronization, commmunication, and protection of shared data between the Ada program entities are addressed. Decomposition or partitioning of the Ada program in a multicomputer system is also studied. Finally, a multicomputer and real time Ada environment is described using FLEX/32 multicomputer system.
The aerothermodynamic environment during the earth return portion of a specific manned Mars mission is studied. Particular attention is given to the earlier smaller crew return capsule and its thermal protection system requirements. Data are presented on the stagnation region of a generic Mars return capsule. Insulation material thicknesses required to maintain allowable structural temperatures throughout a prolonged heat soak period are estimated.
Sputter-deposited SiO(X) (where X between 1.9 and 2.0) thin film coatings have been found to be durable to atomic oxygen. Such coatings will be used to protect polyimide Kapton photovoltaic array blankets from atomic oxygen attack in low earth orbit (LEO) on the Space Station Freedom (SSF). Monte Carlo modeling of atomic oxygen attack at defect sites in protected Kapton exposed in laboratory RF plasma ashers and on solar tracking photovoltaic arrays in space has been conducted to enable understanding of degradation processes relevant to the durability of the SSF solar array blanket. SiO(X) protective coating performance data from RF plasma asher tests will be presented, along with Monte Carlo modeling considerations, to enable the projection of in-space durability of the SSF solar array blankets based on ground laboratory test results.
A training method for preventing the occurrence of motion sickness in humans, called autogenic-feedback training (AFT), is described. AFT is based on a combination of biofeedback and autogenic therapy which involves training physiological self-regulation as an alternative to pharmacological management. AFT was used to reliably increase tolerance to motion-sickness-inducing tests in both men and women ranging in age from 18 to 54 years. The effectiveness of AFT is found to be significantly higher than that of protective adaptation training. Data obtained show that there is no apparent effect from AFT on measures of vestibular perception and no side effects.
The Technology Applications (TAG) Group at NASA Langley Research Center has currently more than 100 technologies that are ripe for commercialization. These technologies are categorized by various sectors including: Energy and the Environment; Materials and Structures; Manufacturing; Information and Communications; Transportation, and Medical/Sensor/ Instrumentation. A requirement that TAG has placed on all technologies ready for licensing is that there will be some university involvement in the technology transfer or knowledge transfer process. This model involves the troika of government (LaRC), industry and university. A number of variations on the Troika Partnership Model (TPM) were developed as a part of this ASEE Fellowship. Furthermore, five technologies were identified - three of which industrial interests have been matched: LaRC-SI, a thermoplastic that can be used as a coating; Variable Geometry Truss Manipulator Arm that can be used for nuclear waste clean -up and as scaffolding; and ADAPT (Approach to Data Management, Archive Protection, and Transmission) is a technology that could be used for a variety of multi-tasking operations over the Internet. The aim of this work was to initiate a Space Act Agreement (SAA) for at least one of these technologies using one of the options of the TPM. A preliminary partnership agreement using the SAA is currently being negotiated with NASA-LaRC, VPI and Virginia Power for the LaRC-SI thermoplastic that will be used as a coating.
It is necessary to integrate a wide variety of technical disciplines to provide an analysis of structural damage to a spacecraft due to hypervelocity impact. There are many uncertainties, and more detailed investigation is warranted, in each technical discipline. However, a total picture of the debris and meteoroid hazard is required to support manned spaceflight in general, and the international Space Station in particular. In the performance of this contract, besides producing a handbook, research and development was conducted in several different areas. The contract was broken into six separate tasks. Each task objectives and accomplishments will be reviewed in the following sections. The Handbook and separate task reports are contained as attachments to the final report. The final section summarizes all of the recommendations coming out of this study. The analyses and comments are general design guidelines and not necessarily applicable to final Space Station designs since several configuration and detailed design changes were being made during the course of this contract. Rather, the analyses and comments may indicate either a point-in-time concept analysis, available test data, or desirable protection goals, not hindered by the design and operation constraints faced by Space Station designers.
Ceramic fiber-reinforced silica aerogels are novel materials for high performance insulation, including thermal protection materials. Experimental data are presented for the thermal and mechanical properties, showing the trends exhibited over a range of fiber loadings and silica aerogel densities. Test results are compared to that of unreinforced bulk aerogels.
During missions to the Moon or Mars, the crew will need medical capabilities to diagnose and treat disease as well as for maintaining their health. The Exploration Medical Capability Element develops medical technologies, medical informatics, and clinical capabilities for different levels of care during space missions. The work done by team members in this Element is leading edge technology, procedure, and pharmacological development. They develop data systems that protect patient's private medical information, aid in the diagnosis of medical conditions, and act as a repository of relevant NASA life sciences experimental studies. To minimize the medical risks to crew health the physicians and scientists in this Element develop models to quantify the probability of medical events occurring during a mission. They define procedures to treat an ill or injured crew member who does not have access to an emergency room and who must be cared for in a microgravity environment where both liquids and solids behave differently than on Earth. To support the development of these medical capabilities, the Element manages the development of medical technologies that prevent, monitor, diagnose, and treat an ill or injured crewmember. The Exploration Medical Capability Element collaborates with the National Space Biomedical Research Institute (NSBRI), the Department of Defense, other Government-funded agencies, academic institutions, and industry.
The Mars Science Laboratory heatshield was designed to withstand a fully turbulent heat pulse based on test results and computational analysis on a pre-flight design trajectory. Instrumentation on the flight heatshield measured in-depth temperatures in the thermal protection system. The data indicate that boundary layer transition occurred at 5 of 7 thermocouple locations prior to peak heating. Data oscillations at 3 pressure measurement locations may also indicate transition. This paper presents the heatshield temperature and pressure data, possible explanations for the timing of boundary layer transition, and a qualitative comparison of reconstructed and computational heating on the as-flown trajectory. Boundary layer Reynolds numbers that are typically used to predict transition are compared to observed transition at various heatshield locations. A uniform smooth-wall transition Reynolds number does not explain the timing of boundary layer transition observed during flight. A roughness-based Reynolds number supports the possibility of transition due to discrete or distributed roughness elements on the heatshield. However, the distributed roughness height would have needed to be larger than the pre-flight assumption. The instrumentation confirmed the predicted location of maximum turbulent heat flux near the leeside shoulder. The reconstructed heat flux at that location is bounded by smooth-wall turbulent calculations on the reconstructed trajectory, indicating that augmentation due to surface roughness probably did not occur. Turbulent heating on the downstream side of the heatshield nose exceeded smooth-wall computations, indicating that roughness may have augmented heating. The stagnation region also experienced heating that exceeded computational levels, but shock layer radiation does not fully explain the differences.
Executing human research on ISS has to navigate a unique risk environment. NASA planning efforts focus on an investigation's in-flight success but much of the threats to research objectives are not mitigated. A balanced requirement set affords the ability to remain flexible for each subject's data set while protecting the study's integrity across all subjects.
While multiple information sources exist concerning surface-level air pollution, no individual source simultaneously provides large-scale spatial coverage, fine spatial and temporal resolution, and high accuracy. It is, therefore, necessary to integrate multiple data sources, using the strengths of each source to compensate for the weaknesses of others. In this study, we propose a method incorporating outputs of NASA’s GEOS Composition Forecasting model system with satellite information from the TROPOMI instrument and ground measurement data on surface concentrations. Although we use ground monitoring data from the Environmental Protection Agency network in the continental United States, the model and satellite data sources used have the potential to allow for global application. This method is demonstrated using surface measurements of nitrogen dioxide as a test case in regions surrounding five major US cities. The proposed method is assessed through cross-validation against withheld ground monitoring sites. In these assessments, the proposed method demonstrates major improvements over two baseline approaches which use ground-based measurements only. Results also indicate the potential for near-term updating of forecasts based on recent ground measurements.
The National Aeronautics and Space Administration has made a commitment to deliver to the International Civil Aviation Organization’s Committee on Aviation Environmental Protection (ICAO CAEP) data defining community response to sounds from supersonic aircraft designed such that their sonic boom is replaced with a soft “thump” sound. The dataset will be a correlation of public perceptions of these sounds to the corresponding acoustic levels. The data will support efforts to develop international standards for permissible noise from supersonic overflight. NASA is planning and preparing for a series of community overflight tests with the X-59, a unique research aircraft capable of generating the “sonic thump”. NASA will begin these tests in 2024. With an eye toward achieving global consensus for noise standards, NASA’s goal is that the community response data be as broadly representative of the response of the international population as possible. As such, NASA is engaging the international regulatory and research communities in both the planning and execution of these tests, through status briefings at ICAO CAEP-sponsored meetings and through workshops with international participation. As part of this outreach NASA held a virtual workshop in December 2021 focused on strategies and considerations for estimating noise exposure levels and conducting surveys to characterize community annoyance levels relative to the “thump” sounds. This paper will present an overview of NASA’s effort, with a focus on the plans and technical goals for the community response tests. In addition, results of the recent workshop will be briefed, including considerations and approaches for ensuring broad representativeness of results and approaches for estimation of the sound levels across the test community. Participant feedback from both the workshop and previous engagements will be discussed, along with how it is being addressed in NASA’s ongoing planning efforts.
NASA is concerned with protecting astronauts from the effects of galactic cosmic radiation and has expended substantial effort in the development of computer models to predict the shielding obtained from various materials. However, these models were only developed for shields up to about 120 g!cm2 in thickness and have predicted that shields of this thickness are insufficient to provide adequate protection for extended deep space flights. Consequently, effort is underway to extend the range of these models to thicker shields and experimental data is required to help confirm the resulting code. In this paper empirically obtained effective dose measurements from aircraft flights in the atmosphere are used to obtain the radiation shielding function of the earth's atmosphere, a very thick shield. Obtaining this result required solving an inverse problem and the method for solving it is presented. The results are shown to be in agreement with current code in the ranges where they overlap. These results are then checked and used to predict the radiation dosage under thick shields such as planetary regolith and the atmosphere of Venus.
Corrosion protection of the space shuttle solid rocket boosters incorporates the use of cathodic protection(anodes) in concert with several coatings systems. The SRB design has large carbon/carbon composites(motor nozzle) electrically connected to an aluminum alloy structure. Early in the STS program, the aluminum structures incurred tremendous corrosive attack due primarily to the galvanic couple to the carbon/carbon nozzle at coating damage locations. Also contributing to the galvanic corrosion problem were stainless steel and titanium alloy components housed within the aluminum structures and electrically connected to the aluminum structures. This paper will highlight the evolution in the protection of the aluminum structures, providing historical information and summary data from the operation of the corrosion protection systems. Also, data and information will be included regarding the evaluation and deployment of inorganic zinc rich primers as anode area on the aluminum structures.