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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 829 records · Page 46
All sourcesNASA NTRSDOE OSTI
NASA NTRS2005

Systems Engineering in NASA's R&TD Programs

Systems engineering is largely the analysis and planning that support the design, development, and operation of systems. The most common application of systems engineering is in guiding systems development projects that use a phased process of requirements, specifications, design, and development. This paper investigates how systems engineering techniques should be applied in research and technology development programs for advanced space systems. These programs should include anticipatory engineering of future space flight systems and a project portfolio selection process, as well as systems engineering for multiple development projects.

Jones, Harry↗
NASA NTRS1994

Materials processing in space tasks. WBS task 5.4: Generic tasks

This task encompassed a wide range of activities related to materials processing in space. For example, all aspects of the space station's flight and ground based systems design were assessed for the Office of Advanced Concepts and Technology (OACT) Space Processing Division Office. Activities for that organization also included the consolidation of space processing payload requirements for the space station and the development of an OACT payload operations plan. Similar duties were performed for the MSFC Payload Project Office. The SPACECOM database was used to conduct preliminary design studies for microgravity payload carriers and to conduct assessments of materials processing technology. Concepts for the Advanced Protein Crystal Growth Facility (APCGF) were developed. Materials processing vent products were analyzed and a furnace facility filter concept was developed using those studies. A preliminary design for a space station aluminum payload rack was developed. Analysis was conducted to characterize the acceleration environment onboard the space shuttle. Equipment for two fluid experiment apparatus was designed and manufactured for the Space Science Laboratory. The Fluids and Materials Experiments (FAME) data base was expanded. Also, Mir payload integration, technology transfer, and spacelab-to-space station transition studies were conducted.

Crull, Robert↗
DOE OSTI2022

Use of Operating Agreements and Energy Storage to Reduce Photovoltaic Interconnection Costs: Conceptual Framework

This report explores one integrated technical and process concept designed to manage interconnection costs and streamline interconnection timelines to support near-term renewable energy deployment. We describe a new agreement between renewable energy developers and utilities, informed by the technical analysis. The agreement defines the operational parameters for a renewable energy system, with the goal of reducing risk and cost to all parties. This work provides a foundation upon which other states and utilities may build proof of concept. This report is supported by a technical analysis that is detailed in a companion report, "Use of Operating Agreements and Energy Storage to Reduce Photovoltaic Interconnection Costs: Technical and Economic Analysis" (McLaren et al. 2022).

14 SOLAR ENERGY↗
NASA NTRSDate not supplied

Characterization of Urban Air Mobility Vehicle Operational Noise and Community Noise Impact

This presentation focuses on the process for predicting urban air mobility (UAM) vehicle noise at the source and how that can be used to estimate and mitigate the impact on the community. Following conceptual design, in which the vehicle is appropriately sized for its intended mission, a comprehensive analysis must be performed for a range of operating conditions spanning the flight envelope to determine the corresponding configurations of the vehicle, that is, the trimmed states. Many UAM vehicles have redundant controls, so the trimmed state for any particular operating condition may not be unique, with some states producing more noise than others. For each trimmed state, the noise produced by each source, for example, steady and unsteady rotor noise, inclusive of propulsion airframe aeroacoustic effects, may be computed and so-called source noise (hemi)spheres generated. The data may be used for analyses supporting noise certification or serve as input to auralizations (turning the numerical data into an audible sound) that can subsequently be used as part of a perception-influenced acoustic design process. Land use planning tools, including those using simulation and integrated modeling approaches, also use these (or derived) data to generate noise exposure maps on the ground. Finally, the data may be used to support development of low noise flight operations using an acoustic flight simulator or acoustically aware flight control.

urban air mobility↗
DOE OSTI2021

Analysis of energetics and economics of sub-ambient hybrid post-combustion carbon dioxide capture

Adsorption of CO 2 from post-combustion flue gas is one of the leading candidates for globally impactful carbon capture systems. In this report, work focused on understanding the opportunities and limitations of sub-ambient CO 2 capture processes utilizing a multistage separation process. A hybrid process design using a combination of pressure-driven separation of CO 2 from flue gas (e.g., adsorption- or membrane-based separation) followed by CO 2 -rich product liquefaction to produce high-purity (>99%) CO 2 at pipeline conditions is considered. The operating pressure of the separation unit is a key cost parameter and also an important process variable that regulates the available heat removal necessary to reach the sub-ambient operating conditions. The economic viability of applying pressure swing adsorption (PSA) processes using fiber sorbent contactors with internal heat management was found to be most influenced by the productivity of the adsorption system, with productivities as high as 0.015 mol CO2 /kg sorb -1 sec -1 being required to reduce costs of capture below $60/ton CO 2 captured. This analysis was carried out using a simplified two-bed process, and thus there is opportunity for further cost reduction with exploration of more complex cycle designs. Three exemplar fiber sorbents (MIL-101(Cr), UiO-66, and zeolite 13X) were considered for application in the sub-ambient process of PSA unit. Among the considered sorbents, zeolite 13X fiber composites were found to perform better at ambient temperatures as compared to sub-ambient. MIL-101(Cr) and UiO-66 fiber composites had improved purity, recovery, and productivity at colder temperatures reducing costs of capture as low as $61/ton CO 2 . Future economic improvement could be achieved by reducing the required operating pressure of the PSA unit and pushing the Pareto frontier closer to the final pipeline requirement via a combination of PSA cycle design and material selection.

42 ENGINEERING↗
DOE OSTI2021

High-level fuel fabrication facility designs from discrete-event simulation

Like other industrial processes, the production of metallic nuclear fuels (MNF) requires that fabrication facilities be able to reliably meet production demands, operate efficiently, and adhere to federal and local safety regulations. In turn, the set of design variables employed by such a facility, such as operations policies, infrastructure and machinery purchased, and the type and number of staff hired, directly impact a facility’s ability to satisfy these goals. Therefore, facility designers must carefully determine which set of design variable values optimally satisfies these constraints. In this paper, we explore how values for these high-level design variables, namely hiring requirements, can be determined in the context of nuclear fuel manufacturing through the coupling of physics-based and discrete-event simulation technologies. Using the Versatile Test Reactor (VTR) program as a case study, we demonstrate how SCALE and MCNP nuclear physics model outputs can be integrated into ExtendSim discrete-event simulation (DES) models of the fuel fabrication process to determine the optimal number of staff hired to ensure fuel production goals are met, operations comply with effective dose limit regulations, and overall project costs are reduced.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2021

AGR-5/6/7 Fuel Fabrication Report

The U.S. Department of Energy Office of Nuclear Energy (DOE NE) and the Idaho National Laboratory (INL) Advanced Reactor Technologies (ART) Advanced Gas Reactor (AGR) Fuel Development and Qualification program (referred to as AGR Fuel program hereafter) are pursuing qualification of tristructural isotropic (TRISO) coated particle fuel for use in high temperature gas cooled reactors (HTGRs). The AGR Fuel program was established to provide a fuel qualification data set in support of the licensing and operation of an HTGR. BWX Technologies Nuclear Operations Group (BWXT-NOG) was subcontracted to fabricate the fuel for the AGR program. Several investments and innovations were realized in preparation to fabricate fuel for the AGR-5/6/7 irradiation experiments that brought fuel fabrication fully out of the laboratory and into engineering-scale operations. These included: • Increased the kernel fabrication line capacity and uniformity • Upgraded ancillary support equipment and processes for the tristructural isotropic (TRISO) coating furnace • Demonstrated efficient production of the matrix precursor powder by dry jet milling of co mingled components • Demonstrated an engineering-scale method for quick and efficient overcoating TRISO particles with the matrix precursor • Demonstrated an automated, multi cavity compacting system with a volumetric feed system • Demonstrated a combined-cycle thermal treatment furnace These changes increased production rates of some of these processes by an order of magnitude or more while eliminating the use of flammable solvents, multiple grinding and sorting operations, and the weighing out of individual die charges. Three fuel kernel lots were fabricated for production of the fuel for AGR-5/6/7. The initial lot (J52R-16-39316) was certified to fuel specifications but was not used because the kernels had a high fraction of internal fissures that caused an unacceptable fraction of the kernels to fragment when charged to the coating furnace where the TRISO coating would be deposited. Fragmented kernels increased the dispersed uranium in the particles and produced a worrisome fraction of dimpled particles with an elevated probability of in-pile failure. After some efforts to identify the cause of the fissure formation, two additional lots were produced with much lower fissure fractions, J52R-16-69317 and 69318. The latter kernel lot was a backup to the first and was not needed. Multiple kernel batches were composited to form each of the lots so as to simulate a commercial-scale operation where kernel batches would also be composited. Multiple TRISO coating runs were performed and the product characterized so that several could be composited into a TRISO lot. TRISO lot J52R-16-98005 conformed to all fuel specifications except the mean outer pyrocarbon (OPyC) layer thickness was thinner than specified. Furthermore, it was determined that the TRISO lot had a dispersed uranium fraction (DUF) that might result in the compacts not meeting the DUF specification. A review of the role of the OPyC layer and consequences of the DUF by the Technical Coordination Team and INL concluded that the fuel was acceptable for use in the AGR-5/6/7 irradiation experiment. The TRISO particles were overcoated with the matrix precursor that had been produced in a jet-milling operation. The overcoating was performed in equipment originally designed to coat pharmaceuticals. The overcoating process performed well; producing highly spherical and uniform overcoats requiring little upgrading and no recycle or rework. TRISO particles were overcoated with the matrix precursor to achieve nominal volumetric packing fractions (PFs) of TRISO particles of 25% and 40% for the irradiation experiments. The 40% PF compacts occupy the first and fifth test capsule in the test train while the inner three capsules are loaded with 25% PF compacts. The resinated graphite matrix precursor powder was a derivative of the German A3-27 matrix formulation, which differs from previous AGR irradiation campaigns that used an A3-3 formulation. Jet milling of the matrix powder precursor produced a finer mean graphite particle size than the milling operations used for the A3-3 matrix powder precursor. Changes made in the matrix formula and equipment yielded compacts with significantly higher matrix density than was attained in previous AGR irradiation campaigns. The changes in the matrix formulation and the means of milling the powders also complicated resolution of the three fuel compact defect fractions, DUF, exposed kernel fraction (EKF), and the silicon carbide defect fraction (SDF). Characterization data from BWXT-NOG had some anomalous results, so samples of the fuel compacts and overcoated TRISO particles were also analyzed by Oak Ridge National Laboratory (ORNL) to ensure that the defect fractions were accurately characterized.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
NASA NTRS1987

Maintainability Program Requirements for Space Systems

This document is established to provide common general requirements for all NASA programs to: design maintainability into all systems where maintenance is a factor in system operation and mission success; and ensure that maintainability characteristics are developed through the systems engineering process. These requirements are not new. Design for ease of maintenance and minimization of repair time have always been fundamental requirements of the systems engineering process. However, new or reusable orbital manned and in-flight maintainable unmanned space systems demand special emphasis on maintainability, and this document has been prepared to meet that need. Maintainability requirements on many NASA programs differ in phasing and task emphasis from requirements promulgated by other Government agencies. This difference is due to the research and development nature of NASA programs where quantities produced are generally small; therefore, the depth of logistics support typical of many programs is generally not warranted. The cost of excessive maintenance is very high due to the logistics problems associated with the space environment. The ability to provide timely maintenance often involves safety considerations for manned space flight applications. This document represents a basic set of requirements that will achieve a design for maintenance. These requirements are directed primarily at manned and unmanned orbital space systems. To be effective, maintainability requirements should be tailored to meet specific NASA program and project needs and constraints. NASA activities shall invoke the requirements of this document consistent with program planning in procurements or on inhouse development efforts.

Source record↗
NASA NTRS1994

Does human cognition allow Human Factors (HF) certification of advanced aircrew systems?

This paper has examined the requirements of HF specification and certification within advanced or complex aircrew systems. It suggests reasons for current inadequacies in the use of HF in the design process, giving some examples in support, and suggesting an avenue towards the improvement of the HF certification process. The importance of human cognition to the operation and performance of advanced aircrew systems has been stressed. Many of the shortfalls of advanced aircrew systems must be attributed to over automated designs that show little consideration on either the mental limits or the cognitive capabilities of the human system component. Traditional approaches to system design and HF certification are set within an over physicalistic foundation. Also, traditionally it was assumed that physicalistic system functions could be attributed to either the human or the machine on a one to one basis. Moreover, any problems associated with the parallel needs, or promoting human understanding alongside system operation and direction, were generally equated in reality by the natural flexibility and adaptability of human skills. The consideration of the human component of a complex system is seen as being primarily based on manifestations of human behavior to the almost total exclusion of any appreciation of unobservable human mental and cognitive processes. The argument of this paper is that the considered functionality of any complex human-machine system must contain functions that are purely human and purely cognitive. Human-machine system reliability ultimately depends on human reliability and dependability and, therefore, on the form and frequency of cognitive processes that have to be conducted to support system performance. The greater the demand placed by an advanced aircraft system on the human component's basic knowledge processes or cognition, rather than on skill, the more insiduous the effects the human may have on that system. This paper discusses one example of an attempt to devise an improved method of specificaiton and certification with relation to the advanced aircrew system, that of the RN Merlin helicopter. The method is realized to have limitations in practice, these mainly associated with the late production of the system specification in relation to the system development process. The need for a careful appreciation of the capabilities and support needs of human cognition within the design process of a complex man machine system has been argued, especially with relation to the concept of system functionality. Unlike the physicalistic Fitts list, a new classification of system functionality is proposed, namely: (1) equipment - system equipment related; (2) cognitive - human cognition related; and (3) associated - necessary combinatin of equipment and cognitive. This paper has not proposed a method for a fuller consideration of cognition within systems design, but has suggested the need for such a method and indicated an avenue towards its development. Finally, the HF certification of advanced aircrew systems is seen as only being possible in a qualified sense until the important functions of human cognition are considered within the system design process. (This paper contains the opinions of its authors and does not necessarily refledt the standpoint of their respective organizations).

Macleod, Iain S.↗
NASA NTRS1993

Construction concepts for precision segmented reflectors

Three construction concepts for deployable precision segmented reflectors are presented. The designs produce reflectors with very high surface accuracies and diameters three to five times the width of the launch vehicle shroud. Of primary importance is the reliability of both the deployment process and the reflector operation. This paper is conceptual in nature, and uses these criteria to present beneficial design concepts for deployable precision segmented reflectors.

Mikulas, Martin M., Jr.↗
NASA NTRS1977

A low-cost system for reception and processing of line-scan data from LANDSAT and other sources

A low-cost transportable earth resources ground station was built in Canada and installed to operational status at Shoe Cove, Newfoundland. The system concepts developed for this station provide timely availability of data in both photographic and digital form. The system was designed with several objectives in mind: (1) to provide a system which could receive, store and process line-scan image data from a wide variety of satellites, most especially the LANDSAT and NOAA (VHRR) series, as well as aircraft scanner data, and data from future remote sensing and meteorological satellites; (2) the system has been designed to be operated by a small staff and to produce black and white images and computer-compatible tapes (CCT's) of all relevant data; (3) the system is compact in its physical design so that it is possible to configure it as a self-contained ground station, housed in a 3 x 12 meter trailer; (4) the system is designed to process all data at real-time rates or better and is designed in a modular fashion so that it can be easily upgraded to do further processing of the data, and/or to handle new satellites and sensors.

Sloan, D. S.↗
NASA NTRS2016

A Robust, Gravity-Insensitive, High-Temperature Condenser for Water Recovery

Regenerative life support systems are vital for NASA's future long-duration human space exploration missions. A Heat Melt Compactor (HMC) system is being developed by NASA to dry and compress trash generated during space missions. The resulting water vapor is recovered and separated from the process gas flow by a gravity-insensitive condenser. Creare is developing a high-temperature condenser for this application. The entire condenser is constructed from metals that have excellent resistance to chemical attack from contaminants and is suitable for high-temperature operation. The metal construction and design configuration also offer greatest flexibility for potential coating and regeneration processes to reduce biofilm growth and thus enhancing the reliability of the condenser. The proposed condenser builds on the gravity-insensitive phase separator technology Creare developed for aircraft and spacecraft applications. This paper will first discuss the design requirements for the condenser in an HMC system that will be demonstrated on the International Space Station (ISS). Then, it will present the overall design of the condenser and the preliminary thermal test results of a subscale condenser. Finally, this paper will discuss the predicted performance of the full-size condenser and the development plan to mature the technology and enhance its long-term reliability for a flight system.

Chen, Weibo↗
NASA NTRS1982

Human factors in operations design

The manner in which organizations develop their organizational structure is considered, taking into account an example in which the environment changes for an older organization. In such cases, it would be preferable to have some theoretical foundation on which to base the restructuring of the organization to meet new environmental needs. A description is given of a theoretic foundation based on the principles of Differentiation/Integration and Procedural/Knowledge based operations. The organizational design principle of Differentiation and Integration has been presented by Lawrence and Lorsch (1969). The differentiation/integration processes are related to the organizational structures presented in studies concerning NASA Deep Space Network (DSN) operations. The principles presented provide valuable tools for analyzing operations organization.

Chafin, R. L.↗
NASA NTRS1975

Power processing for electric propulsion

The potential of achieving up to 30 per cent more spacecraft payload or 50 per cent more useful operating life by the use of electric propulsion in place of conventional cold gas or hydrazine systems in science, communications, and earth applications spacecraft is a compelling reason to consider the inclusion of electric thruster systems in new spacecraft design. The propulsion requirements of such spacecraft dictate a wide range of thruster power levels and operational lifetimes, which must be matched by lightweight, efficient, and reliable thruster power processing systems. This paper will present electron bombardment ion thruster requirements; review the performance characteristics of present power processing systems; discuss design philosophies and alternatives in areas such as inverter type, arc protection, and control methods; and project future performance potentials for meeting goals in the areas of power processor weight (10 kg/kW), efficiency (approaching 92 per cent), reliability (0.96 for 15,000 hr), and thermal control capability (0.3 to 5 AU).

Finke, R. C.↗
NASA NTRS1996

Applications of Genetic Methods to NASA Design and Operations Problems

We review four recent NASA-funded applications in which evolutionary/genetic methods are important. In the process we survey: the kinds of problems being solved today with these methods; techniques and tools used; problems encountered; and areas where research is needed. The presentation slides are annotated briefly at the top of each page.

Laird, Philip D.↗
NASA NTRS2017

Radar Ambiguities and Signal Processing Design Tradeoffs in the REASON Radar Sounder

NASA’s planned Europa Clipper mission would carry a radar sounder which operates at HF and VHF frequencies that can penetrate the icy shell of Europa. The sounder would be used to characterize subsurface bodies of liquid water and to measure the thickness of the icy shell. The spacecraft would make observations during flyby to reduce radiation exposure. The varying geometry during the flyby is expected to cause varying radar ambiguity and surface clutter contamination. At the same time, data down-link restrictions would require on-board pulse summation to reduce data volume which would require on-board Doppler filtering to control clutter and ambiguity contamination levels. This paper will study some of the design trade-offs involved in specifying the on-board Doppler filtering.

Hawkins, D.↗
DOE OSTI2021

Supercritical Carbon Dioxide Primary Power Large-Scale Pilot Plant

The United States electrical power generation fleet encompasses a wide range of technologies, ranging from traditional combustion-based power generation, to nuclear power, to renewable energy. While the distribution of these assets continues to shift due to economic and regulatory influences, coal combustion continues to be a key part of the US energy portfolio. Despite the relative maturity of coal combustion technology, improvements in overall fuel-to-power efficiency and generation flexibility are still possible and will improve both the economic and environmental factors of coal combustion. Echogen Power Systems proposes to lead a world-class team including the University of Missouri, Electric Power Research Institute and Louis Perry Associates in the design, construction and operation of a 10MWe coal-fired supercritical carbon dioxide (sCO 2 ) large-scale pilot. This transformational technology uses sCO 2 as a working fluid instead of water to achieve high thermodynamic efficiencies that can significantly exceed advanced steam-Rankine cycles. Further, the compact nature of sCO 2 turbomachinery offers capital cost and footprint advantages, and the low maintenance of a water-free power cycle can significantly reduce operation and maintenance (O&M) costs over conventional steam-Rankine systems. Recent integration studies of sCO 2 with coal combustion power plants highlight the significant improvements in plant efficiency that sCO 2 can offer relative to even advanced steam Rankine cycles. At commercial scales, coal-sCO 2 plant net efficiency is predicted to be 39-44.0% (HHV), or 10-20% higher output than conventional steam-Rankine systems, which will significantly improve the competitiveness of coal-fired generation. This proposal builds upon projects previously funded by the Department of Energy, including DE-FE0025959 (High-Efficiency Thermal Integration of Closed Supercritical CO 2 Brayton Power Cycles with Oxy-Fired Heaters) and DE-NE0008470 (Conceptual Design for sCO 2 Power Cycle Test Facility). An appropriately-scaled and properly designed and operated pilot project is essential to overcome the natural risk-aversion of the power generation industry and project financing community. The 10 MWe coal-fired sCO 2 pilot power plant proposed herein will reduce the technical and economic risk of this transformational technology, enabling commercial deployment at the conclusion of the project. For the second phase of this project, Echogen lead a team that completed and refined the pilot system conceptual system and key component designs resulting in the completion of a front-end-engineering-design (FEED) study, completed the NEPA review process, completed the permitting process for construction and operation, refined the techno-economic analysis of the proposed system at commercial scale and received commitments for Phase III cost share. The end result of the program will be to demonstrate the technical and economic superiority of the sCO 2 power cycle for coal-fired operation. Major risk elements will have been retired with sufficient operation at high power to enable the power generation industry to move forward with the first commercial deployment of this transformational system.

01 COAL, LIGNITE, AND PEAT↗
NASA NTRS1989

A definition study of the on-orbit assembly operations for the outboard photovoltaic power modules for Space Station Freedom

A concept is described for the assembly of the outboard PV modules for Space Station Freedom. Analysis of the on-orbit assembly operations was performed using CADAM design graphics software. A scenario for assembly using the various assembly equipment, as currently defined, is described in words, tables and illustrations. This work is part of ongoing studies in the area of space station assembly. The outboard PV module and the assembly equipment programs are all in definition and preliminary design phases. An input is provided to the design process of assembly equipment programs. It is established that the outboard PV module assembly operations can be performed using the assembly equipment currently planned in the Space Station Freedom Program.

Sours, Thomas J.↗