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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 91 records · Page 5

All sources NASA NTRS DOE OSTI

NASA NTRS1975

The Pioneer Projects - Economical exploration of the solar system

The interplanetary Pioneer missions are reviewed in terms of management implications and cost control. The responsibilities, organizational structure, and management practices of the Pioneer Projects are presented. The lines of authority and areas of responsibility of the principal organizational elements supporting the Pioneer missions are identified, and the methods employed for maintaining effective and timely interactions among these elements are indicated. The technical and administrative functions of various organizational elements of the project are described. The management and control of activities prior to and during the hardware procurement phase are described to indicate the basis for obtaining visibility of the technical progress, utilization of resources, and cost performance of the contractors and other institutions supporting the Pioneer projects.

Spahr, J. R.↗

NASA NTRS1993

Lessons learned - MO&DA at JPL

The issues of how to avoid future surprise growth in Mission Operations and Data Analysis (MO&DA) costs and how to minimize total MO&DA costs for planetary missions are discussed within the context of JPL mission operations support. It is argued that there is no simple, single solution: the entire Project life-cycle must be addressed. It is concluded that cost models that can predict both MO&DA cost as well as Ground System development costs are needed. The first year MO&DA budget plotted against the total of ground and flight systems developments is shown. In order to better recognize changes and control costs in general, a modified funding line item breakdown is recommended to distinguish between development costs (prelaunch and postlaunch) and MO&DA costs.

Handley, Thomas H., Jr.↗

NASA NTRS2002

Innovative, High-Pressure, Cryogenic Control Valve: Short Face-to-Face, Reduced Cost

A control valve that can throttle high-pressure cryogenic fluid embodies several design features that distinguish it over conventional valves designed for similar applications. Field and design engineers worked together to create a valve that would simplify installation, trim changes, and maintenance, thus reducing overall cost. The seals and plug stem packing were designed to perform optimally in cryogenic temperature ranges. Unlike conventional high-pressure cryogenic valves, the trim size can be changed independent of the body. The design feature that provides flexibility for changing the trim is a split body. The body is divided into an upper and a lower section with the seat ring sandwiched in between. In order to maintain the plug stem packing at an acceptable sealing temperature during cryogenic service, heat-exchanging fins were added to the upper body section. The body is made of stainless steel. The seat ring is made of a nickel-based alloy having a coefficient of thermal expansion less than that of the body material. Consequently, when the interior of the valve is cooled cryogenically, the body surrounding the seat ring contracts more than the seat ring. This feature prevents external leakage at the body-seat joint. The seat ring has been machined to have small, raised-face sealing surfaces on both sides of the seal groove. These sealing surfaces concentrate the body bolt load over a small area, thereby preventing external leakage. The design of the body bolt circle is different from that of conventional highpressure control valves. Half of the bolts clamp the split body together from the top, and half from the bottom side. This bolt-circle design allows a short, clean flow path, which minimizes frictional flow losses. This bolt-circle design also makes it possible to shorten the face-toface length of the valve, which is 25.5 in. (65 cm). In contrast, a conventional, high-pressure control valve face-to-face dimension may be greater than 40 in. (>1 m) long.

Source record↗

DOE OSTI2012

Microworlds, Simulators, and Simulation: Framework for a Benchmark of Human Reliability Data Sources

In this paper, we propose a method to improve the data basis of human reliability analysis (HRA) by extending the data sources used to inform HRA methods. Currently, most HRA methods are based on limited empirical data, and efforts to enhance the empirical basis behind HRA methods have not yet yielded significant new data. Part of the reason behind this shortage of quality data is attributable to the data sources used. Data have been derived from unrelated industries, from infrequent risk-significant events, or from costly control room simulator studies. We propose a benchmark of four data sources: a simplified microworld simulator using unskilled student operators, a full-scope control room simulator using skilled student operators, a full-scope control room simulator using licensed commercial operators, and a human performance modeling and simulation system using virtual operators. The goal of this research is to compare findings across the data sources to determine to what extent data may be used and generalized from cost effective sources.

99 GENERAL AND MISCELLANEOUS↗

NASA NTRS2004

Innovative, High-Pressure, Cryogenic Control Valve: Short Face-to-Face, Reduced Cost

A control valve that can throttle high pressure cryogenic fluid embodies several design features that distinguish it over conventional valves designed for similar applications. Field and design engineers worked together to create a valve that would simplify installation, trim changes, and maintenance, thus reducing overall cost. The seals and plug stem packing were designed to perform optimally in cryogenic temperature ranges. Unlike conventional high-pressure cryogenic valves, the trim size can be changed independent of the body. The design feature that provides flexibility for changing the trim is a split body. The body is divided into an upper and a lower section with the seat ring sandwiched in between. In order to maintain the plug stem packing at an acceptable sealing temperature during cryogenic service, heat-exchanging fins were added to the upper body section (see figure). The body is made of stainless steel.

Wilkes, Karlin↗

NASA NTRS2003

Innovative, High-Pressure, Cryogenic Control Valve: Short Face-to-Face, Reduced Cost

Wilkes, Karlin↗

NASA NTRS1974

An evaluation of contractor projected and actual costs

GSFC contractors with cost-plus contracts provide cost estimates for each of the next four quarters on a quarterly basis. Actual expenditures over a two-year period were compared to the estimates, and the data were sorted in different ways to answer several questions and give quantification to observations, such as how much does the accuracy of estimates degrade as they are made further into the future? Are estimates made for small dollar amounts more accurate than for large dollar estimates? Other government agencies and private companies with cost-plus contracts may be interested in this analysis as potential methods of contract management for their organizations. It provides them with the different methods one organization is beginning to use to control costs.

Kwiatkowski, K. A.↗

NASA NTRS2016

Analysis of Satellite and Airborne Imagery for Detection of Water Hyacinth and Other Invasive Floating Macrophytes and Tracking of Aquatic Weed Control Efficacy

Waterways of the Sacramento San Joaquin Delta have recently become infested with invasive aquatic weeds such as floating water hyacinth (Eichhoria crassipes) and water primrose (Ludwigia peploides). These invasive plants cause many negative impacts, including, but not limited to: the blocking of waterways for commercial shipping and boating; clogging of irrigation screens, pumps and canals; and degradation of biological habitat through shading. Zhang et al. (1997, Ecological Applications, 7(3), 1039-1053) used NASA Landsat satellite imagery together with field calibration measurements to map physical and biological processes within marshlands of the San Francisco Bay. Live green biomass (LGB) and related variables were correlated with a simple vegetation index ratio of red and near infra-red bands from Landsat images. More recently, the percent (water area) cover of water hyacinth plotted against estimated LGB of emergent aquatic vegetation in the Delta from September 2014 Landsat imagery showed an 80 percent overall accuracy. For the past two years, we have partnered with the U. S. Department of Agriculture (USDA) and the Department of Plant Sciences, University of California at Davis to conduct new validation surveys of water hyacinth and water primrose coverage and LGB in Delta waterways. A plan is underway to transfer decision support tools developed at NASA's Ames Research Center based on Landsat satellite images to improve Delta-wide integrated management of floating aquatic weeds, while reducing chemical control costs. The main end-user for this application project will be the Division of Boating and Waterways (DBW) of the California Department of Parks and Recreation, who has the responsibility for chemical control of water hyacinth in the Delta.

Agriculture↗

NASA NTRS2017

Using Satellite Remote Sensing to Map Changes in Aquatic Invasive Plant Cover in the Sacramento-San Joaquin River Delta of California

Waterways of the Sacramento San Joaquin Delta have recently become infested with invasive aquatic weeds such as floating water hyacinth (Eichhoria crassipes) and water primrose (Ludwigia peploides). These invasive plants cause many negative impacts, including, but not limited to: the blocking of waterways for commercial shipping and boating; clogging of irrigation screens, pumps and canals; and degradation of biological habitat through shading. Zhang et al. (1997, Ecological Applications, 7(3), 1039-1053) used NASA Landsat satellite imagery together with field calibration measurements to map physical and biological processes within marshlands of the San Francisco Bay. Live green biomass (LGB) and related variables were correlated with a simple vegetation index ratio of red and near infra-red bands from Landsat images. More recently, the percent (water area) cover of water hyacinth plotted against estimated LGB of emergent aquatic vegetation in the Delta from September 2014 Landsat imagery showed a 80% overall accuracy. For the past two years, we have partnered with the U. S. Department of Agriculture (USDA) and the Department of Plant Sciences, University of California at Davis to conduct new validation surveys of water hyacinth and water primrose coverage and LGB in Delta waterways. A plan is underway to transfer decision support tools developed at NASA's Ames Research Center based on Landsat satellite images to improve Delta-wide integrated management of floating aquatic weeds, while reducing chemical control costs. The main end-user for this application project will be the Division of Boating and Waterways (DBW) of the California Department of Parks and Recreation, who has the responsibility for chemical control of water hyacinth in the Delta.

Map Changes↗

NASA NTRS2008

Orbit Control Operations for the Cassini-Huygens Mission

The Cassini-Huygens spacecraft was launched in 1997 as an international and collaborative mission to study Saturn and its many moons. After a seven-year cruise, Cassini began orbiting Saturn for a four- year tour. This tour consists of 157 planned maneuvers, and their back-up locations, designed to target 52 encounters, mostly of Saturn's largest moon Titan. One of the mission's first activities was to release the Huygens probe to Titan in December 2004. Currently in its last year of the prime mission, Cassini-Huygens continues to obtain valuable data on Saturn, Titan, and Saturn's other satellites. Return of this information is in large part due to a healthy spacecraft and successful navigation. A two-year extended mission, beginning July 2008, will offer the opportunity to continue science activities. With a demanding navigation schedule that compares with the prime tour, the Cassini Navigation team relies on operations procedures developed during the prime mission to carry-out the extended mission objectives. Current processes for orbit control operations evolved from the primary navigational requirement of staying close to predetermined targeting conditions according to Cassini science sequence planning. The reference trajectory is comprised of flyby conditions to be accomplished at minimal propellant cost. Control of the planned reference trajectory orbit, and any trajectory updates, is achieved with the execution of Orbit Trim Maneuvers (OTMs). The procedures for designing, processing, and analyzing OTMs during Cassini operations is presented. First, a brief overview of the Cassini-Huygens Mission is given, followed by a general description of navigation. Orbit control and maneuver execution methods are defined, along with an outline of the orbit control staffing and operations philosophy. Finally, an example schedule of orbit control operations is shown.

navigation↗

DOE OSTI2022

A low-cost centralized HVAC control system solution for energy savings, load shedding, and improved maintenance

University campuses rely on centralized controls for managing and optimizing complex HVAC systems in larger buildings. However, most campuses also have many smaller buildings with packaged HVAC systems controlled by a stand-alone thermostat. Even when these distributed and often overlooked systems have modern programmable thermostats, they cannot be centrally monitored or controlled, and they are typically not programmed adequately. This paper describes the implementation of a low-cost centralized control solution for these systems serving smaller campus buildings, mostly under 5,000 sf and representative of light commercial spaces. Thanks to advances in technology spurred by residential and commercial IoT developments, simple networked thermostat solutions exist that can easily replace original thermostats, and, connect these systems to a web-based portal for monitoring and control. We show that, with small customizations, these platforms can be integrated into facility management workflows. Beyond the energy savings potential from improved scheduling and closer management of these systems, there are significant advantages for maintenance crews since these systems can now be monitored on smart phones or tablets. A grid-responsive load-shedding program has also been implemented for additional cost savings. The networked thermostats can also be connected to additional systems such as economizer controls for improved ventilation management and energy savings. With data from these systems integrated centrally, it can also be used for improved analytics and fault detection. A toolkit has been developed to share the program with other campuses, whether for energy savings, improved management of ventilation, or a more proactive maintenance approach.

Fauchier-Magnan, Nicolas↗

DOE OSTI2014

Pinning impulsive control algorithms for complex network

In this paper, we further investigate the synchronization of complex dynamical network via pinning control in which a selection of nodes are controlled at discrete times. Different from most existing work, the pinning control algorithms utilize only the impulsive signals at discrete time instants, which may greatly improve the communication channel efficiency and reduce control cost. Two classes of algorithms are designed, one for strongly connected complex network and another for non-strongly connected complex network. It is suggested that in the strongly connected network with suitable coupling strength, a single controller at any one of the network's nodes can always pin the network to its homogeneous solution. In the non-strongly connected case, the location and minimum number of nodes needed to pin the network are determined by the Frobenius normal form of the coupling matrix. In addition, the coupling matrix is not necessarily symmetric or irreducible. Illustrative examples are then given to validate the proposed pinning impulsive control algorithms.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

NASA NTRS2012

The Economics of NASA Mission Cost Reserves

Increases in NASA mission costs have led to analysis of the causes and magnitude of historical mission overruns as well as mitigation and prevention attempts. This paper hypothesizes that one cause is that the availability of reserves may reduce incentives to control costs. We draw a comparison to the insurance concept of moral hazard, and we use actuarial techniques to better understand the increase in mission costs due to the availability of reserves. NASA's CADRe database provided the data against which we tested our hypothesis and discovered that there is correlation between the amount of available reserves and project overruns, particularly for mission hardware cost increases. We address the question of how to prevent reserves from increasing mission spending without increasing cost risk to projects.

Whitley, Sally↗

DOE OSTI2025

Techno-Economic Analysis for the Addition of a Thermal Energy Storage System to a Central Plant

Increasing energy demand and rising peak loads present significant challenges for energy management in commercial and institutional settings. As climate change drives greater cooling needs, central plants must navigate the complex tradeoffs between operational efficiency, cost control, and grid stability. Thermal energy storage (TES) systems offer a viable solution by shifting energy consumption from peak to off-peak periods, thereby reducing peak demand, lowering utility expenses, and improving grid resilience. However, the success of TES implementation hinges on appropriate system sizing, effective control strategies, and alignment with local utility rate structures. This article presents a techno-economic analysis of integrating a chilled water TES system into the central plant at California State University, Dominguez Hills. Drawing on historical load profiles and utility tariffs, we assess three TES sizing approaches and their corresponding control strategies from both energy and economic perspectives. This article utilizes a model-based approach to assess the impact of TES sizing and control strategies on the techno-economic feasibility of integrating TES into an existing central plant. The models employed for this analysis were calibrated using 4 years of historical data. Here, the results demonstrated that utility tariffs and the campus's operational profiles dictate the most feasible sizing and control methods. The findings offer valuable insights for institutions and commercial building managers exploring sustainable energy solutions. By demonstrating how optimized TES strategies can improve operational efficiency while achieving financial savings, this study highlights the potential for TES to align performance with cost effectiveness in real-world applications.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2025

Universal energy-speed-accuracy trade-offs in driven nonequilibrium systems

The connection between measure theoretic optimal transport and dissipative nonequilibrium dynamics provides a language for quantifying nonequilibrium control costs, leading to a collection of thermodynamic speed limits, which rely on the assumption that the target probability distribution is perfectly realized. This is almost never the case in experiments or numerical simulations, so here we address the situation in which the external controller is imperfect. We obtain a lower bound for the dissipated work in generic nonequilibrium control problems that (1) is asymptotically tight and (2) matches the thermodynamic speed limit in the case of optimal driving. Along with analytically solvable examples, we refine this imperfect driving notion to systems in which the controlled degrees of freedom are slow relative to the nonequilibrium relaxation rate, and identify independent energy contributions from fast and slow degrees of freedom. Furthermore, we develop a strategy for optimizing minimally dissipative protocols based on optimal transport flow matching, a generative machine learning technique. Furthermore, this latter approach ensures the scalability of both the theoretical and computational framework we put forth. Crucially, we demonstrate that we can compute the terms in our bound numerically using efficient algorithms from the computational optimal transport literature and that the protocols we learn saturate the bound.

59 BASIC BIOLOGICAL SCIENCES↗

NASA NTRS1992

Consortium for materials development in space interaction with Space Station Freedom

The Consortium for Materials Development in Space (CMDS) is one of seventeen Centers for the Commercial Development of Space (CCDS) sponsored by the Office of Commercial Programs of NASA. The CMDS formed at the University of Alabama in Huntsville in the fall of 1985. The Consortium activities therefore will have progressed for over a decade by the time Space Station Freedom (SSF) begins operation. The topic to be addressed here is: what are the natural, mutually productive relationships between the CMDS and SSF? For management and planning purposes, the Consortium organizes its activities into a number of individual projects. Normally, each project has a team of personnel from industry, university, and often government organizations. This is true for both product-oriented materials projects and for infrastructure projects. For various projects Space Station offers specific mutually productive relationships. First, SSF can provide a site for commercial operations that have evolved as a natural stage in the life cycle of individual projects. Efficiency and associated cost control lead to another important option. With SSF in place, there is the possibility to leave major parts of processing equipment in SSF, and only bring materials to SSF to be processed and return to earth the treated materials. This saves the transportation costs of repeatedly carrying heavy equipment to orbit and back to the ground. Another generic feature of commercial viability can be the general need to accomplish large through-put or large scale operations. The size of SSF lends itself to such needs. Also in addition to processing equipment, some of the other infrastructure capabilities developed in CCDS projects may be applied on SSF to support product activities. The larger SSF program may derive mutual benefits from these infrastructure abilities.

Lundquist, Charles A.↗

DOE OSTI2012

Integrated Warm Gas Multicontaminant Cleanup Technologies for Coal-Derived Syngas

One of the key obstacles for the introduction of commercial gasification technology for the production of power with Integrated Gasification Combined Cycle (IGCC) plants or the production of value added chemicals, transportation fuels, and hydrogen has been the cost of these systems. This situation is particularly challenging because the United States has ample coal resources available as raw materials and effective use of these raw materials could help us meet our energy and transportation fuel needs while significantly reducing our need to import oil. One component of the cost of these systems that faces strong challenges for continuous improvement is removing the undesirable components present in the syngas. The need to limit the increase in cost of electricity to < 35% for new coal-based power plants which include CO 2 capture and sequestration addresses both the growing social concern for global climate change resulting from the emission of greenhouse gas and in particular CO 2 and the need to control cost increases to power production necessary to meet this social objective. Similar improvements to technologies for trace contaminants are getting similar pressure to reduce environmental emissions and reduce production costs for the syngas to enable production of chemicals from coal that is cost competitive with oil and natural gas. RTI, with DOE/NETL support, has been developing sorbent technologies that enable capture of trace contaminants and CO 2 at temperatures above 400 °F that achieve better capture performance, lower costs and higher thermal efficiency. This report describes the specific work of sorbent development for mercury (Hg), arsenic (As), selenium (Se), cadmium (Cd), and phosphorous (P) and CO 2 removal. Because the typical concentrations of Hg, As, Se, Cd, and P are less than 10 ppmv, the focus has been on single-use sorbents with sufficient capacity to ensure replacement costs are cost effective. The research in this report describes the development efforts which expand this sorbent development effort to include Se, Cd, and P as well as Hg and As. Additional research has focused on improving removal performance with the goal of achieving effluent concentrations that are suitable for chemical production applications. By contrast, sorbent development for CO 2 capture has focused on regenerable sorbents that capture the CO 2 byproduct at higher CO 2 pressures. Previous research on CO 2 sorbents has demonstrated that the most challenging aspect of developing CO 2 sorbents is regeneration. The research documented in this report investigates options to improve regeneration of the CO 2 capture sorbents. This research includes effort on addressing existing regeneration limitations for sorbents previously developed and new approaches that focus initially on the regeneration performance of the sorbent.

01 COAL, LIGNITE, AND PEAT↗

DOE OSTI2017

Regulatory Incentives and Disincentives for Utility Investments in Grid Modernization

Electric power is America's most capital-intensive industry, with more than $100 billion invested each year in energy infrastructure. Investment needs are likely to grow as electric utilities make power systems more reliable and resilient, deploy advanced digital technologies, and facilitate new services to meet some consumers' expectations for greater choice and control. But do current regulatory approaches provide the appropriate incentives for grid modernization investments? This report presents three perspectives: -Financial analyst Steve Kihm begins by explaining that any major investor-owned electric utility that wants to raise capital today can do so at a reasonable cost. The question is whether utility managers want to raise capital for grid modernization. Specifically, they look for investments that create the most value for their existing shareholders. In cases where grid modernization investments are not the best choice in terms of shareholder value, Kihm describes shareholder incentive mechanisms that regulators could consider to encourage such investments when they are in the public interest. -From an institutional perspective, Dr. Janice Beecher finds that the traditional rate-base/rate of return regulatory model provides powerful incentives for utilities to pursue investments, cost control, efficiency and even innovation, and it is well suited to the policy objectives of grid modernization. Prudence of grid modernization investments (fair returns) depends on careful evaluation of the specific asset, and any special incentives (bonus returns) should be used only if they promote economic efficiency consistent with the core goals of economic regulation. According to Beecher, realizing the promises of grid modernization depends on effective implementation of the traditional regulatory model and ratemaking tools to serve the public interest. -Conversely, former commissioner and clean energy consultant Ron Lehr says that rapid electric industry changes require a better alignment of utility investment incentives with changes challenging the electricity sector, emerging grid modernization options and benefits, and public policies. For example, investor-owned utilities typically have an incentive to make capital investments, but rarely to employ expense-based solutions, since utilities do not earn profits on expenses. Further, Lehr cites a variety of factors that stand in the way of creating well targeted and well aligned utility incentives, including litigated regulatory processes. These may be a poor choice for finding the right balance among competing interests, establishing rules of prospective application, justifying demonstrations of new technologies and approaches to meeting emerging consumer demands, and keeping pace with rapid change.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗