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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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NASA NTRS2015

Astrobiology, Mars Exploration and Lassen Volcanic National Park

The search for evidence of life beyond Earth illustrates how the charters of NASA and the National Park Service share common ground. The mission of NPS is to preserve unimpaired the natural and cultural resources of the National Park System for the enjoyment, education and inspiration of this and future generations. NASA's Astrobiology program seeks to understand the origins, evolution and distribution of life in the universe, and it abides by the principles of planetary stewardship, public outreach, and education. We cannot subject planetary exploration destinations to Earthly biological contamination both for ethical reasons and to preserve their scientific value for astrobiology. We respond to the public's interest in the mysteries of life and the cosmos by honoring their desire to participate in the process of discovery. We involve youth in order to motivate career choices in science and technology and to perpetuate space exploration. The search for evidence of past life on Mars illustrates how the missions of NASA and NPS can become synergistic. Volcanic activity occurs on all rocky planets in our Solar System and beyond, and it frequently interacts with water to create hydrothermal systems. On Earth these systems are oases for microbial life. The Mars Exploration Rover Spirit has found evidence of extinct hydrothermal system in Gusev crater, Mars. Lassen Volcanic National Park provides a pristine laboratory for investigating how microorganisms can both thrive and leave evidence of their former presence in hydrothermal systems. NASA scientists, NPS interpretation personnel and teachers can collaborate on field-oriented programs that enhance Mars mission planning, engage students and the public in science and technology, and emphasize the ethics of responsible exploration.

Lassen Volcanic National Park↗

NASA NTRS1985

Effects of surface chemistry on hot corrosion life

This program has its primary objective: the development of hot corrosion life prediction methodology based on a combination of laboratory test data and evaluation of field service turbine components which show evidence of hot corrosion. The laboratory program comprises burner rig testing by TRW. A summary of results is given for two series of burner rig tests. The life prediction methodology parameters to be appraised in a final campaign of burner rig tests are outlined.

Fryxell, R. E.↗

NASA NTRS1998

Smart Sensor System for NDE or Corrosion in Aging Aircraft

The extension of the operation life of military and civilian aircraft rather than replacing them with new ones is increasing the probability of aircraft component failure as a result of aging. Aircraft that already have endured a long srvice life of more than 40 years are now being considered for another 40 years of service.

monitoring system mathematical transformation oper↗

NASA NTRS1993

Hierarchical Simulation of Hot Composite Structures

Computational procedures are described to simulate the thermal and mechanical behavior of high temperature metal matrix composites (HT-MMC) in the following three broad areas: (1) Behavior of HT-MMC's from micromechanics to laminate via Metal Matrix Composite Analyzer (METCAN), (2) tailoring of HT-MMC behavior for optimum specific performance via Metal Matrix Laminate Tailoring (MMLT), and (3) HT-MMC structural response for hot structural components via High Temperature Composite Analyzer (HITCAN). Representative results from each area are presented to illustrate the effectiveness of computational simulation procedures. The sample case results show that METCAN can be used to simulate material behavior such as strength, stress-strain response, and cyclic life in HTMMC's; MMLT can be used to tailor the fabrication process for optimum performance such as that for in-service load carrying capacity of HT-MMC's; and HITCAN can be used to evaluate static fracture and fatigue life of hot pressurized metal matrix composite rings.

Chamis, C. C.↗

NASA NTRS2000

International Space Station Sustaining Engineering: A Ground-Based Test Bed for Evaluating Integrated Environmental Control and Life Support System and Internal Thermal Control System Flight Performance

As the International Space Station's (ISS) various habitable modules are placed in service on orbit, the need to provide for sustaining engineering becomes increasingly important to ensure the proper function of critical onboard systems. Chief among these are the Environmental Control and Life Support System (ECLSS) and the Internal Thermal Control System (ITCS). Without either, life onboard the ISS would prove difficult or nearly impossible. For this reason, a ground-based ECLSS/ITCS hardware performance simulation capability has been developed at NASA's Marshall Space Flight Center. The ECLSS/ITCS Sustaining Engineering Test Bed will be used to assist the ISS Program in resolving hardware anomalies and performing periodic performance assessments. The ISS flight configuration being simulated by the test bed is described as well as ongoing activities related to its preparation for supporting ISS Mission 5A. Growth options for the test facility are presented whereby the current facility may be upgraded to enhance its capability for supporting future station operation well beyond Mission 5A. Test bed capabilities for demonstrating technology improvements of ECLSS hardware are also described.

Ray, Charles D.↗

NASA NTRS1994

Budget estimates: Fiscal year 1994. Volume 3: Research and program management

The research and program management (R&PM) appropriation provides the salaries, other personnel and related costs, and travel support for NASA's civil service workforce. This FY 1994 budget funds costs associated with 23,623 full-time equivalent (FTE) work years. Budget estimates are provided for all NASA centers by categories such as space station and new technology investments, space flight programs, space science, life and microgravity sciences, advanced concepts and technology, center management and operations support, launch services, mission to planet earth, tracking and data programs, aeronautical research and technology, and safety, reliability, and quality assurance.

Source record↗

NASA NTRS1986

Space station science lab module

The Science Lab Module (SLM), a key component of the proposed Space Station (SS) orbiting complex, is undergoing intensive study during the project design phase which is currently underway. The SLM is one of the two laboratory modules which, together with two habitation modules, comprise the core elements of the SS reference configurations. Current project emphasis is to configure the SLM as a national science laboratory module facility which would have four major functions: maximize life sciences research potential, support operations of attached payloads, provide shirtsleeve environment for other payload instrument servicing, and support other science requirements. The design studies are focusing on outfitting a common module basic design to accommodate the four specific functions. Although design work for outfitting the SLM for life sciences research is underway, science requirements for the other sciences and functions are not as well developed.

Devincenzi, D. L.↗

DOE OSTI2026

Spectral Flux Measurements on SNS Direct Geometry Spectrometers at IRP-2 End-of-Life

The Inner Reflector Plug (IRP) of the Spallation Neutron Source (SNS) was replaced during the SNS shutdown period beginning 25 November 2025. This IRP, IRP-2, was first placed in service in May 2018, and was in use for 42.5 GW-hrs of operation, somewhat longer than its original design life of 30 GW-hrs, or even a refined estimate of 33 GW-hrs for the water moderator poison plate and 39 GW-hrs on the decoupled-poisoned hydrogen moderator decoupler (Gallmeier, Lu, and Iverson 2018). The time-integrated power history for IRP-2 is tracked in Figure 1.

43 PARTICLE ACCELERATORS↗

NASA NTRSDate not supplied

Rendezvous Fiducial Implementation in A Space Vehicle Life Cycle

Rendezvous and capture of legacy satellites is significantly more challenging than rendezvous and capture of satellites prepared with servicing inter-faces. Rendezvous fiducial markers (or fiducials) are a low cost, low mass, simple but effective tool to bridge the gap between legacy and prepared satellites. This paper presents the motivation for rendezvous fiducials as well as analysis demonstrating the improvement in state estimation accuracy with fiducials on the client satellite or space object. Included herein is a review of the life cycle of rendezvous fiducials such as the incorporation into a space vehicle design and photo documentation of the pre-launch installation. Answers to key implementation questions are answered: How many fiducials? Where should they be placed? What does the eventual servicer need to know? NASA case studies from the recently launched James Webb Space Telescope and in-design Nancy Grace Roman Space Telescope are included for illustration.

Fiducial↗

NASA NTRS1989

An Earth Orbiting Satellite Service and Repair Facility

A conceptual design was produced for the Geosynchronous Satellite Servicing Platform (GSSP), an orbital facility capable of repairing and servicing satellites in geosynchronous orbit. The GSSP is a man-tended platform, which consists of a habitation module, operations module, service bay and truss assembly. This design review includes an analysis of life support systems, thermal and power requirements, robotic and automated systems, control methods and navigation, and communications systems. The GSSP will utilize existing technology available at the time of construction, focusing mainly on modifying and integrating existing systems. The entire facility, along with two satellite retrieval vehicles (SRV), will be placed in geosynchronous orbit by the Advanced Launch System. The SRV will be used to ferry satellites to and from the GSSP. Technicians will be transferred from Earth to the GSSP and back in an Apollo-derived Crew Transfer Capsule (CTC). These missions will use advanced telerobotic equipment to inspect and service satellites. Four of these missions are tentatively scheduled per year. At this rate, the GSSP will service over 650 satelites during the projected 25 year lifespan.

Berndt, Andrew↗

NASA NTRS1963

Nickel-cadmium cells for the spacecraft battery

The storage battery for the Telstar satellite must undergo frequent charge-discharge cycles; in addition, it is subject to overcharge during a substantial portion of its life. Nickel-cadmium cells were chosen as best capable of satisfactory long-time operation under these conditions. A design and selection program was undertaken to ensure that Ni-Cd cores would meet objectives imposed by battery service conditions, and the cell enclosure was designed to minimize electrolyte leakage. Selection, qualification, and life tests indicated that a storage battery using the cell design would perform satisfactorily. To date, the only failures occurring during continuing life tests have been among cells subjected to 100 per cent discharge daily; this operation is far in excess of the expected duty cycle of satellite cells.

TELSTAR SATELLITE↗

NASA NTRS1972

Space Shuttle bipropellant RCS engine.

The requirements of the Space Shuttle bipropellant reaction control system engine technology contract and the scheduled contract effort are presented herein. The requirements included an engine concept scalable from 400 to 1100 lbf, with a 100 mission life employing N2O4/MMH propellants. Emphasis is placed on reusability and minimum post-flight servicing. The engine components are reviewed and their selection is supported by tradeoff analyses, thrust chamber firing test data, materials test data, and metallurgical evaluations. The materials test data indicate that the proposed silicide coated columbium chamber and uncoated columbium injector have the potential of meeting the mission life requirements. The engine valve trade studies resulted in the selection of a torque motor operated bipropellant valve configuration. Fuel vortex film cooling of the insulated chamber is described together with the fuel vortex film cooling scaling parameter and its verification by test data to a thrust level of 5500 lbf.

Sanscrainte, W.↗

DOE OSTI2026

The Next Stage for Smart Cities: Metrics to Spur an Evolution from Technology for Efficiency to Technology for People's Needs

The Smart Cities movement is about a decade old, energized by the USDOT Smart Cities grant that sparked cities to dream big. Now, 10 years later, and multitudes of conferences and papers later, the biggest question regarding Smart Cities is whether any progress has been made? Smart Cities forums are typically led by the technology sector, either telecommunications, internet access, or most recently artificial intelligence (AI) concerns. Each of these areas have grown and found new applications in the context of Smart Cities, however, these technology applications are just tools toward ends. Do digital communications and assistance enable or foster improved access to real, tactile, non-virtual goods and services such as transportation, food, housing, trash removal, health care, education, social interaction? These and other topics are not 'big tech', but are each critical to quality of life outcomes and are day-to-day necessities, comprising many of the touch points through which citizens interact with municipal agencies. Regarding Smart Cities, relationships have not been fully refined as to how best to merge the emerging generation of technology and related trends with more mundane but essential requirements of tactile services. How should municipal managers and operators bring the range of new technology tools (e.g. on-demand transit, automated vehicles, digital connectivity) to bear to improve functions serving real- physical- non-virtual needs? How do we make cities more efficient in providing access to services and opportunities for improved quality of life? This paper examines the current Smart City movement, emerging trends, and the need to put metrics with respect to the delivery, access, and provision of real-life needs. Using a few case studies of past, present, and projected future scenarios, this paper attempts to bring Smart Cities into the real cities domain, perhaps pushing the moniker away from 'Smart' to 'Efficient' - something that can be measured, counted, and assessed. Through the consideration of the next stage of the evolution of cities from 'Smart' to 'Efficient', the combined efforts and experience of multiple researchers at the NREL and their network of collaborators highlights the need for updates metrics that can be used to start guiding efforts toward productive initiatives to improve quality of life.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

NASA NTRS2019

Building an Economical and Sustainable Lunar Infrastructure to Enable Human Missions

To enable return of human missions to the surface of the Moon sustainably, a new study was initiated to assess the feasibility of developing an evolvable, economical and sustainable lunar surface infrastructure using a public-private partnerships approach. This approach would establish partnerships between NASA and private industry to mutually develop lunar surface infrastructure capabilities to support robotic missions initially and later evolve to full-scale commercial infrastructure services in support of human missions. These infrastructure services may range from power systems, communication and navigation systems, thermal management systems, mobility systems, water and propellant production to life support systems for human habitats. The public-private partnerships approach for this study leverages best practices from NASA’s Commercial Orbital Transportation Services (COTS) program which introduced an innovative and economical approach for partnering with industry to develop commercial cargo transportation services to the International Space Station (ISS). In this approach, NASA and industry partners shared cost and risk throughout the development phase which led to dramatic reduction in development and operations costs of these transportation services. Following this approach, a Lunar COTS concept was conceived to develop cost-effective surface infrastructure capabilities in partnership with industry to provide economical, operational services for small-scale robotic missions. As a result, a self-contained lunar infrastructure system with power, thermal, communication and navigation elements was conceptually designed to increase capability, extend mission duration and reduce cost of small-scale robotic missions. To support human missions, this work has now been extended to analyze full-scale lunar infrastructure systems. This infrastructure system should have capabilities to support human missions from a few days to several months with minimal maintenance and replacement of parts. This infrastructure system should also maximize the use of existing lunar resources, such as, oxygen from regolith, water from ice deposits at the poles, and use of metals, such as iron and aluminum, from lunar regolith. The plan includes a buildup of these capabilities using a phased-development approach that will eventually lead to operational infrastructure services. By partnering with industry to develop and operate the infrastructure services using the COTS model, this plan should also result in significant cost savings and increased reliability. This paper will describe the Lunar COTS concept goals, objectives and approach for developing an evolvable, economical and sustainable human lunar infrastructure as well as the challenges and opportunities for development.

Zuniga, Allison↗

NASA NTRS2019

Building an Economical and Sustainable Lunar Infrastructure to Enable Human Lunar Missions

To enable return of human missions to the surface of the Moon sustainably, a new study was initiated to assess the feasibility of developing an evolvable, economical and sustainable lunar surface infrastructure using a public-private partnerships approach. This approach would establish partnerships between NASA and private industry to mutually develop lunar surface infrastructure capabilities to support robotic missions initially and later evolve to full-scale commercial infrastructure services in support of human missions. These infrastructure services may range from power systems, communication and navigation systems, thermal management systems, mobility systems, water and propellant production to life support systems for human habitats. The public-private partnerships approach for this study leverages best practices from NASA's Commercial Orbital Transportation Services (COTS) program which introduced a new innovative and economical approach for partnering with industry to develop commercial cargo transportation services to the International Space Station (ISS). In this approach, NASA and industry partners shared cost and risk throughout the development phase which led to dramatically reducing development and operations costs of these transportation services. Following this approach, a Lunar COTS concept was conceived to follow this model and gradually develop cost-effective surface infrastructure capabilities in partnership with industry to provide economical, operational services for small-scale robotic missions. To support human missions, this work has now been extended to analyze full-scale lunar infrastructure systems. This infrastructure system will have capabilities to support human missions from a few days to several months and will also maximize the use of existing lunar resources, such as, water from ice deposits at the lunar poles. The plan includes a gradual buildup of these capabilities using a phased-development approach that will eventually lead to operational infrastructure services. By partnering with industry to develop and operate the infrastructure services using the COTS model, this plan will also result in significant cost savings, reduced risk and increased reliability. This paper will describe the Lunar COTS concept goals, objectives and approach for developing an evolvable, economical and sustainable human lunar infrastructure as well as the challenges and opportunities for development.

Lunar Surface Systems↗

NASA NTRS2003

Life Cycle Testing of Viscoelastic Material for Hubble Space Telescope Solar Array 3 Damper

During the March 2002 Servicing Mission by Space Shuttle (STS 109), the Hubble Space Telescope (HST) was refurbished with two new solar arrays that now provide all of its power. These arrays were built with viscoelastic/titanium dampers, integral to the supporting masts, which reduce the interaction of the wing bending modes with the Telescope. Damping of over 3% of critical was achieved. To assess the damper s ability to maintain nominal performance over the 10-year on-orbit design goal, material specimens were subjected to an accelerated life test. The test matrix consisted of scheduled events to expose the specimens to pre-determined combinations of temperatures, frequencies, displacement levels, and numbers of cycles. These exposure events were designed to replicate the life environment of the damper from fabrication through testing to launch and life on-orbit. To determine whether material degradation occurred during the exposure sequence, material performance was evaluated before and after the accelerated aging with complex stiffness measurements. Based on comparison of pre- and post-life-cycle measurements, the material is expected to maintain nominal performance through end of life on-orbit. Recent telemetry from the Telescope indicates that the dampers are performing nominally.

Maly, Joseph R.↗

DOE OSTI2019

Current State-of-Practice in Dam Safety Risk Assessment

Dams provide significant benefits to the nation, serving as critical infrastructure to deliver water retention and control throughout the United States (US). Major cities could not function without the fresh water supply stored in dammed reservoirs, and many electrical systems rely on dependable hydroelectric power supply. Dams on rivers across the country protect communities against destructive flood impacts while providing navigable waters for transportation, irrigation for agriculture, and various opportunities for recreation. While dams provide many essential services, dam failure flooding can present significant risks to property and life. Over decades of experience, dam safety practices, including risk assessment, have evolved as engineering knowledge, scientific understanding, and technological advancements grow. This project summarizes the current state-of-practice in dam safety risk assessment.

13 HYDRO ENERGY↗

NASA NTRS1972

A comparison of reliability and conventional estimation of safe fatigue life and safe inspection intervals

Both the conventional and reliability analyses for determining safe fatigue life are predicted on a population having a specified (usually log normal) distribution of life to collapse under a fatigue test load. Under a random service load spectrum, random occurrences of load larger than the fatigue test load may confront and cause collapse of structures which are weakened, though not yet to the fatigue test load. These collapses are included in reliability but excluded in conventional analysis. The theory of risk determination by each method is given, and several reasonably typical examples have been worked out, in which it transpires that if one excludes collapse through exceedance of the uncracked strength, the reliability and conventional analyses gave virtually identical probabilities of failure or survival.

Hooke, F. H.↗