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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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This paper presents the results of studies that provide an overview of expected sensitivities to cycle rate, temperature, lead stiffness, and strain-cycle depth.
This paper presents the fundamental equations governing cyocooler mechanical efficiency and launch vibration response in terms of their implications for cooler design.
To meet an important need within the space community for a reliable and accurate database of cryocooler performance, the Jet Propulsion Laboratory (JPL), under SDIO/Air Force Sponsorship, is conducting an extensive space cryocooler characterization program involving long-life cryocoolers submitted by world-wide manufacturers.
Inclusion of ecosystem services (ES) information into national-scale development and climate adaptation planning has yet to become common practice, despite demand from decision makers. Identifying where ES originate and to whom the benefits flowunder current and future climate conditionsis especially critical in rapidly developing countries, where the risk of ES loss is high. Here, using Myanmar as a case study, we assess where and how ecosystems provide key benefits to the countrys people and infrastructure. We model the supply of and demand for sediment retention, dry-season baseflows, flood risk reduction and coastal storm protection from multiple beneficiaries. We find that locations currently providing the greatest amount of services are likely to remain important under the range of climate conditions considered, demonstrating their importance in planning for climate resilience. Overlap between priority areas for ES provision and biodiversity conservation is higher than expected by chance overall, but the areas important for multiple ES are underrepresented in currently designated protected areas and Key Biodiversity Areas. Our results are contributing to development planning in Myanmar, and our approach could be extended to other contexts where there is demand for national-scale natural capital information to shape development plans and policies
The field of adaptive structures has expanded dramatically during the past few years. Inch worm actuators are commercially available, but do not meet all the desired static and dynamic features in one actuator. The objective of the development of the Mighty Worm was to develop such an actuator. The Mighty Work actuator consists of a piezoelectric transducer, its housing, and two clamping devices. In operation, Mighty Worm either pushes or pulls a load.
As the advancement of In-Situ Resource Utilization concepts and systems continue to develop, applicable technology development and maturation continues in parallel. While there are many different ways to use the resources found on other bodies, one of the most prevalent suggested applications is the manufacturing of propellants. One of the key technologies for the eventual use of these propellant production based ISRU systems is the liquefaction and storage of the produced propellants. The most mentioned propellant combinations include oxygen-hydrogen and oxygen-methane. The liquefaction of oxygen in these systems will be different than oxygen liquefaction systems on Earth, which mainly revolves around the distillation of air. These systems have been developed conceptually and many of the components have been previously tested or are in development. However, the need to demonstrate the system level operations still exists. The demonstration of a prototypical oxygen liquefaction system using tube-on-tank broad area cooling was completed to better understanding system level operations during liquefaction activities. Demonstration testing included system performance determination, constant liquefaction demonstrations, and transient liquefaction demonstrations. The demonstrations showed the operational capabilities of the tube-on-tank system with an integrated cryocooler. Additional testing explored subsurface vs ullage introduction of the gaseous oxygen flow stream as well as demonstrating a novel fiber optic sensor that measured the temperature gradients along the fluid center line within the tank.
As the advancement of In-Situ Resource Utilization concepts and systems continue to develop, applicable technology development and maturation continues in parallel. While there are many different ways to use the resources found on other bodies, one of the most prevalent suggested applications is the manufacturing of propellants. One of the key technologies for the eventual use of these propellant production based ISRU systems is the liquefaction and storage of the produced propellants. The most mentioned propellant combinations include oxygen-hydrogen and oxygen-methane. The liquefaction of oxygen in these systems will be different than that on Earth, which mainly revolves around the distillation of air. These systems have been developed conceptually and many of the components have been previously tested or are in development. However, the need to demonstrate the system level operations still exists. The demonstration of a prototypical oxygen liquefaction system using tube-on-tank broad area cooling was completed to better understanding system level operations during liquefaction activities. Demonstration testing included system performance determination, constant liquefaction demonstrations, and transient liquefaction demonstrations. The demonstrations showed the operational capabilities of the tube-on-tank system with an integrated cryocooler. Additional testing explored subsurface vs ullage introduction of the gaseous oxygen flow stream as well as demonstrating a novel fiber optic sensor that measured the temperature gradients along the fluid center line within the tank.