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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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108 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS1991

NASA information systems commonality and convergence

Efforts to identify high payback functions performed by the Office of Space Science Applications (OSSA) data systems package existing operationally proven implementations as system building blocks and foster their use in the OSSA environment. An overview is given of the current state of OSSA data systems and the major challenges facing system developers over the next five years. Current trends in system commonality are discussed, and development is examined in the context of system design. Central system engineering approaches to solving the commonality and interoperability challenges are described. Efforts to package three diverse building blocks and to foster their reuse are documented.

Handley, Thomas H., Jr.↗
NASA NTRS1992

Advanced propulsion for LEO-Moon transport. 1: A method for evaluating advanced propulsion performance

This report describes a study to evaluate the benefits of advanced propulsion technologies for transporting materials between low Earth orbit and the Moon. A relatively conventional reference transportation system, and several other systems, each of which includes one advanced technology component, are compared in terms of how well they perform a chosen mission objective. The evaluation method is based on a pairwise life-cycle cost comparison of each of the advanced systems with the reference system. Somewhat novel and economically important features of the procedure are the inclusion not only of mass payback ratios based on Earth launch costs, but also of repair and capital acquisition costs, and of adjustments in the latter to reflect the technological maturity of the advanced technologies. The required input information is developed by panels of experts. The overall scope and approach of the study are presented in the introduction. The bulk of the paper describes the evaluation method; the reference system and an advanced transportation system, including a spinning tether in an eccentric Earth orbit, are used to illustrate it.

Stern, Martin O.↗
NASA NTRS1992

Advanced propulsion for LEO-Moon transport. 3: Transportation model

A simplified computational model of low Earth orbit-Moon transportation system has been developed to provide insight into the benefits of new transportation technologies. A reference transportation infrastructure, based upon near-term technology developments, is used as a departure point for assessing other, more advanced alternatives. Comparison of the benefits of technology application, measured in terms of a mass payback ratio, suggests that several of the advanced technology alternatives could substantially improve the efficiency of low Earth orbit-Moon transportation.

Henley, Mark W.↗
NASA NTRS1994

Hot gas ingestion effects on fuel control surge recovery and AH-1 rotor drive train torque spikes

This report summarizes the work accomplished through computer simulation to understand the impact of the hydromechanical turbine assembly (TA) fuel control on rocket gas ingestion induced engine surges on the AH-1 (Cobra) helicopter. These surges excite the lightly damped torsional modes of the Cobra rotor drive train and can cause overtorqueing of the tail rotor shaft. The simulation studies show that the hydromechanical TA control has a negligible effect on drive train resonances because its response is sufficiently attenuated at the resonant frequencies. However, a digital electronic control working through the TA control's separate, emergency fuel metering system has been identified as a solution to the overtorqueing problem. State-of-the-art software within the electronic control can provide active damping of the rotor drive train to eliminate excessive torque spikes due to any disturbances including engine surges and aggressive helicopter maneuvers. Modifications to the existing TA hydromechanical control are relatively minor, and existing engine sensors can be utilized by the electronic control. Therefore, it is concluded that the combination of full authority digital electronic control (FADEC) with hydromechanical backup using the existing TA control enhances flight safety, improves helicopter performance, reduces pilot workload, and provides a substantial payback for very little investment.

Tokarski, Frank↗
NASA NTRS1993

Impact of composites on future transport aircraft

In the current environment, new technology must be cost-effective in addition to improving operability. Various approaches have been used to determine the 'hurdle' or 'breakthrough' return that must be achieved to gain customer commitment for a new product or aircraft, or in this case, a new application of the technology. These approaches include return-on-investment, payback period, and addition to net worth. An easily understood figure-of-merit and one used by our airline customers is improvement in direct operating cost per seat-mile. Any new technology must buy its way onto the aircraft through reduction in direct operating cost (DOC).

Kinder, Robert H.↗
NASA NTRS1996

Feasibility Study of a Rotorcraft Health and Usage Monitoring System (HUMS): Results of Operator's Evaluation

The objective was to evaluate the feasibility of a state-of-the-art health and usage monitoring system (HUMS) to provide monitoring of critical mechanical systems on the helicopter, including motors, drive train, engines, and life-limited components. The implementation of HUMS and cost integration with current maintenance procedures was assessed from the operator's viewpoint in order to achieve expected benefits from these systems, such as enhanced safety, reduced maintenance cost, and increased availability. An operational HUMS that was installed and operated under an independent flight trial program was used as a basis for this study. The HUMS equipment and software were commercially available. Based on the results of the feasibility study, the HUMS used in the flight trial program generally demonstrated a high level of reliability in monitoring the rotor system, engines, drive train, and life-limited components. The system acted as a sentinel to warn of impending failures. A worn tail rotor pitch bearing was detected by HUMS, which had the capability for self testing to diagnose system and sensor faults. Examples of potential payback to the operator with HUMS were identified, including reduced insurance cost through enhanced safety, lower operating costs derived from maintenance credits, increased aircraft availability, and improved operating efficiency. The interfacing of HUMS with current operational procedures was assessed to require only minimal revisions to the operator's maintenance manuals. Finally the success in realizing the potential benefits from HUMS technology was found to depend on the operator, helicopter manufacturer, regulator (FAA), and HUMS supplier working together.

Romero, Raylund↗
NASA NTRS2000

Terrestrial Applications of Zero Boil-Off Cryogen Storage

Storing cryogenic propellants with zero boil off (ZBO) using a combination of active (cryocoolers) and passive technologies has recently received a great deal of attention for applications such as future long-term space missions. This paper will examine a variety of potential near-term terrestrial applications for ZBO and, where appropriate, provide a rough order of magnitude cost benefit of implementing ZBO technology. NASA's Space Shuttle power system uses supercritical propellant tanks, which are filled several days before launch. If the launch does not occur within 48-96 hours, the tanks must be drained and refilled, further delaying the launch. By implementing ZBO, boil off could be eliminated and pad hold time extended. At the launch site, vented liquid hydrogen (LH2) storage dewars lose 1200-1600 gal/day through boiloff. Implementing ZBO would eliminate this, saving $300,000-$400,000 per year. Similarly, overland trucking of LH2 from the supplier to the launch site via roadable dewars results in a cryogen loss of ten percent per tanker (1500 gal/tanker). Providing a cryocooler on board the rig would prevent this loss. Previous work investigating variable density insulation found that a 50% reduction in evaporation from a 6000 gallon dewar would save $5000 per year. For a 20 year dewar lifetime, the payback period would be less than two years. Similar benefits could be realized at other storage facilities across the nation. Within the superconductivity community, there is skepticism about using coolers, based upon reliability concerns. By providing a cooler on the dewar, lifetime could be extended while retaining fail-safe capability. If the cooler failed, it would merely lower the storage life of the dewar.

Salerno, L. J.↗
NASA NTRS2000

An Assessment of the Technical Readiness of the Vapor Phase Catalytic Ammonia Removal Process (VPCAR) Technology

This poster provides an assessment of the technical readiness of the Vapor Phase Catalytic Ammonia Removal Process (VPCAR). The VPCAR technology is a fully regenerative water recycling technology designed specifically for applications such as a near term Mars exploration mission. The VPCAR technology is a highly integrated distillation/catalytic oxidation based water processor. It is designed to accept a combined wastewater stream (urine, condensate, and hygiene) and produces potable water in a single process step which requires -no regularly scheduled re-supply or maintenance for a 3 year mission. The technology is designed to be modular and to fit into a volume comparable to a single International Space Station Rack (when sized for a crew of 6). This poster provides a description of the VPCAR technology and a summary of the current performance of the technology. Also provided are the results of two separate NASA sponsored system trade studies which investigated the potential payback of further development of the VPCAR technology.

Flynn, Michael↗
NASA NTRS2002

An Analysis for an Internet Grid to Support Space Based Operations

Currently, and in the past, dedicated communication circuits and "network services" with very stringent performance requirements have been used to support manned and unmanned mission critical ground operations at GSFC, JSC, MSFC, KSC and other NASA facilities. Because of the evolution of network technology, it is time to investigate other approaches to providing mission services for space ground and flight operations. In various scientific disciplines, effort is under way to develop network/komputing grids. These grids consisting of networks and computing equipment are enabling lower cost science. Specifically, earthquake research is headed in this direction. With a standard for network and computing interfaces using a grid, a researcher would not be required to develop and engineer NASA/DoD specific interfaces with the attendant increased cost. Use of the Internet Protocol (IP), CCSDS packet spec, and reed-solomon for satellite error correction etc. can be adopted/standardized to provide these interfaces. Generally most interfaces are developed at least to some degree end to end. This study would investigate the feasibility of using existing standards and protocols necessary to implement a SpaceOps Grid. New interface definitions or adoption/modification of existing ones for the various space operational services is required for voice both space based and ground, video, telemetry, commanding and planning may play a role to some undefined level. Security will be a separate focus in the study since security is such a large issue in using public networks. This SpaceOps Grid would be transparent to users. It would be anagulous to the Ethernet protocol's ease of use in that a researcher would plug in their experiment or instrument at one end and would be connected to the appropriate host or server without further intervention. Free flyers would be in this category as well. They would be launched and would transmit without any further intervention with the researcher or ground ops personnel. The payback in developing these new approaches in support of manned and unmanned operations is lower cost and will enable direct participation by more people in organizations and educational institutions in space based science. By lowering the high cost of space based operations and networking, more resource will be available to the science community for science. With a specific grid in place, experiment development and operations would be much less costly by using standardized network interfaces. Because of the extensive connectivity on a global basis, significant numbers of people would participate in science who otherwise would not be able to participate.

Bradford, Robert↗
NASA NTRS2005

The Decompression Sickness and Venous Gas Emboli Consequences of Air Breaks During 100% Oxygen Prebreathe

Not enough is known about the increased risk of hypobaric decompression sickness (DCS) and production of venous (VGE) and arterial (AGE) gas emboli following an air break in an otherwise normal 100% resting oxygen (O2) prebreathe (PB), and certainly a break in PB when exercise is used to accelerate nitrogen (N2) elimination from the tissues. Current Aeromedical Flight Rules at the Johnson Space Center about additional PB payback times are untested, possibly too conservative, and therefore not optimized for operational use.

Conkin, Johnny↗
NASA NTRS2004

The Decompression Sickness and Venous Gas Emboli Consequences of Air Breaks During 100% Oxygen Prebreathe

Not enough is known about the increased risk of hypobaric decompression sickness (DCS) and production of venous (VGE) and arterial (AGE) gas emboli following an air break in an otherwise normal 100% resting oxygen (O2) prebreathe (PB), and certainly a break in PB when exercise is used to accelerate nitrogen (N2) elimination from the tissues. Current Aeromedical Flight Rules at the Johnson Space Center about additional PB payback times are untested, possibly too conservative, and therefore not optimized for operational use. A 10 min air break at 90 min into a 120 min PB that includes initial dual-cycle ergometry for 10 min will show a measurable increase in the risk of DCS and VGE after ascent to 4.3 psia compared to a 10 min break at 15 min into the PB, or when there is no break in PB. Data collection with humans begins in 2005, but here we first evaluate the hypothesis using three models of tissue N2 kinetics: Model I is a simple single half-time compartment exponential model, Model II is a three compartment half-time exponential model, and Model III is a variable half-time compartment model where the percentage of maximum O2 consumption for the subject during dual-cycle ergometry exercise defines the half-time compartment. Model I with large rate constants to simulate an exercise effect always showed a late break in PB had the greatest consequence. Model II showed an early break had the greatest consequence. Model III showed there was no difference between early or late break in exercise PB. Only one of these outcomes will be observed when humans are tested. Our results will favor one of these models, and so advance our understanding of tissue N2 kinetics, and of altitude DCS after an air break in PB.

Conkin, J.↗
NASA NTRS2010

Feasibility Investigation for a Solar Power Generation Facility

The Energy Policy Act of 2005 states that by fiscal year 2013, at least 7.5% of the energy consumed by the government must be renewable energy. In an effort to help meet this goal, Johnson Space Center (JSC) is considering installing a solar power generation facility. The purpose of this project is to conduct a feasibility investigation for such a facility. Because Kennedy Space Center (KSC) has a solar power generation facility, the first step in this investigation is to learn about KSC's facility and obtain information on how it was constructed. After collecting this information, the following must be determined: the amount of power desired, the size of the facility, potential locations for it, and estimated construction and maintenance costs. Contacts with JSC's energy provider must also be established to determine if a partnership would be agreeable to both parties. Lastly, all of this data must be analyzed to decide whether or not JSC should construct the facility. The results from analyzing the data collected indicate that a 200 kW facility would provide enough energy to meet 1% of JSC's energy demand. This facility would require less than 1 acre of land. In the map below, potential locations are shown in green. The solar power facility is projected to cost $2 M. So far, the information collected indicates that such a facility could be constructed. The next steps in this investigation include contacting JSC's energy provider, CenterPoint Energy, to discuss entering a partnership; developing a life cycle cost analysis to determine payback time; developing more detailed plans; and securing funding.

Nathan, Lakshmi↗
NASA NTRS2013

Robonaut 2 - Preparing for Intra-Vehicular Mobility on the International Space Station

Robonaut 2 (R2) has been undergoing experimental trials on board the International Space Station (ISS) for more than a year. This upper-body anthropomorphic robotic system shown in Figure 1 has been making steady progress after completing its initial checkout. R2 demonstrated free space motion, physically interacted with its human crew mates, manipulated interfaces on its task board and has even used its first tool. This steady growth in capability will lead R2 to its next watershed milestone. Developers are currently testing prototype robotic climbing appendages and a battery backpack in preparation of sending flight versions of both subsystems to the ISS in late 2013. Upon integration of its new components, R2 will be able to go mobile inside the space station with a twofold agenda. First, R2 will learn to maneuver in microgravity in the best possible laboratory for such a task. Second, it will start providing early payback to the ISS program by helping with intra-vehicular (IVA) maintenance tasks. The experience gained inside the ISS will be invaluable in reducing risk when R2 moves to its next stage and is deployed as an extra-vehicular (EVA) tool. Even on its current fixed base stanchion, R2 has already shown its capability of performing several maintenance tasks on the ISS. It has measured the air flow through one of the stations vents and provided previously unavailable real time flow data to ground operators. R2 has cleaned its first handrail, exciting some crew members that perhaps Saturday morning housekeeping on the station may someday become a task they can hand off to their robotic colleague. Other tasks, including using radio frequency identification (RFID) tools for inventory tasks or vacuuming air filters, have also been suggested and will be explored. Once mobile, R2 will take on these tasks and more to free up crew time for more important science and exploration pursuits. In addition to task exploration, research and testing is happening on orbit to prepare for R2 mobility operations. The current vision system in R2 s head is being used to identify and localize IVA handrails throughout the US Lab and ground control software is being updated and integrated in advance of supporting mobility operations.

Badger, Julia↗
NASA NTRSDate not supplied

In-Situ Resource Utilization Options for the Moon and Mars

In-Situ Resource Utilization (ISRU) is key to enabling extended presence at exploration locations. NASA’s focus for ISRU to date has been human exploration locations: the Moon and Mars. Likewise the primary target for ISRU has been the production of mission consumables for propulsion and life support. Producing oxygen alone from minerals on the Moon or atmosphere on Mars can provide the majority of these consumables. However, accessing water at either location allows for full propellant production (fuel and oxidizer) as well as other applications (eg life support). Current and previous study efforts have looked at mission architectures and ISRU mass payback for these options. Studies have also identified gaps in information needed to design effective ISRU hardware and choose best architectures

In-Situ Resource Utilization↗
DOE OSTI2025

Rooftop Unit (RTU) Maintenance Guide

The commercial buildings industry has long emphasized affordability, energy efficiency, and useful service life in rooftop unit (RTU) equipment. The trade-offs between these characteristics can impact decisions about the initial cost of equipment and ongoing operating costs. Often, the desire for lower initial costs leads to adoption of low-efficiency systems or neglect of proper maintenance in the interest of short-term cost savings. Maintenance of these systems is a critical step to ensure system efficiency and reliability, low operating costs, and a reasonable payback period. This guide is intended for facility managers who own or are interested in purchasing and installing RTUs and need to familiarize themselves with the maintenance requirements. This resource contains best practices, important considerations, and additional information related to commercial RTU equipment, but does not replace manufacturer-specific instructions.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2025

Digital Transformation for the Existing Fleet: Where to Start?

To remain economically viable in today’s electricity marketplace, nuclear power plants are replacing old analog equipment with modern digital tools. Having information available in an electronic format allows most work processes to become more efficient by automating simple, time-consuming tasks. However, with thousands of routine work processes performed every day, it can be difficult for the plants to know where to begin. We partnered with a nuclear utility to develop a novel assessment tool that measures seven health indicators for each work process performed, providing a rapid digital status report of the plant. The assessment tool is inexpensive and user-friendly, administered remotely, and automatically customized to each employee. Data from 167 employees representing different perspectives were analyzed to identify optimal candidates for digital initiatives that yield the highest payback for increased process efficiencies. We ranked by a priority index to ensure that processes with a good combination of time savings and digital opportunity were at the top. The focus was on determining a maximum investment to ensure that the cost savings from these initiatives are positive over a specified period. We identified potential cost savings of $2.6m, $1.3m and $1.2m for our top priority processes. By using our novel assessment tool to determine the digital status of the plant’s work processes, they were provided with a starting point for target candidates that would most benefit from a digital initiative. Our analysis helps stakeholders understand the financial impact of digital initiatives and identify maximum investment amounts when seeking technical solutions.

assessment↗
DOE OSTI2026

Passive Energy-Saving Solutions for Clothes Dryers: A Modeling and Experimental Study for Improved Efficiency and Affordability

Dryers are integral appliances in modern households, yet their significant power consumption remains a critical challenge for reducing energy bills and upgrades. This work presents the outcomes of a comprehensive investigation aimed at lowering the operating energy costs of the dryer through modeling and experimental approaches. Specifically, the objectives of this research are twofold: (1) to reduce energy consumption without negatively impacting drying performance or time; and (2) to ensure affordability by developing retrofittable solutions characterized by low cost and a quick payback period. These strategies promise universal applicability to all dryer categories, encompassing both gas and electric models, by tackling core issues such as unnecessary heat loss and excess energy supply, both prevalent across dryer designs. Our methodology combines robust modeling frameworks and experimental validation to target energy efficiency improvements through three primary pathways: (1) effective heat loss management using ultralow-cost insulation materials tailored for dryer systems; (2) heat management across the drying cycle, facilitated by passive heat transfer mechanisms, and (3) optimization of heat supply to the load to ensure precise energy delivery, minimizing waste. These innovations are designed to seamlessly integrate with existing dryer configurations, providing a scalable and retrofittable solution that ensures affordability without requiring substantial redesigns or expensive components. Using these methods, the study demonstrates improvement opportunities in dryer energy consumption while maintaining the desired performance. The modeling component utilizes computational simulations to evaluate the thermal and energy performance of these innovations under varied operational conditions, providing foundational insights for experimental design. By addressing critical areas such as heat loss, energy recovery, and supply optimization, this work proposes impactful solutions for lowering the energy costs in domestic clothes dryers. The ultralow-cost, retrofittable nature of the proposed strategies ensures widespread adoption potential across diverse dryer categories, making significant strides toward affordable household energy practices.

Cheekatamarla, Praveen [ORNL] (ORCID:0000000248827↗