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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 271 records · Page 15
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

CELCAP: A Computer Model for Cogeneration System Analysis

A description of the CELCAP cogeneration analysis program is presented. A detailed description of the methodology used by the Naval Civil Engineering Laboratory in developing the CELCAP code and the procedures for analyzing cogeneration systems for a given user are given. The four engines modeled in CELCAP are: gas turbine with exhaust heat boiler, diesel engine with waste heat boiler, single automatic-extraction steam turbine, and back-pressure steam turbine. Both the design point and part-load performances are taken into account in the engine models. The load model describes how the hourly electric and steam demand of the user is represented by 24 hourly profiles. The economic model describes how the annual and life-cycle operating costs that include the costs of fuel, purchased electricity, and operation and maintenance of engines and boilers are calculated. The CELCAP code structure and principal functions of the code are described to how the various components of the code are related to each other. Three examples of the application of the CELCAP code are given to illustrate the versatility of the code. The examples shown represent cases of system selection, system modification, and system optimization.

Source record↗
NASA NTRS1986

Vacuum pumps and systems: A review of current practice

A review of the fundamental characteristics of the many types of vacuum pumps and vacuum pumping systems is given. The optimum pumping range, relative cost, performance limitations, maintenance problems, system operating costs and similar subjects are discussed. Experiences from the thin film deposition, chemical processing, material handling, food processing and other industries, as well as space simulation are used to support conclusions and recommendations.

Giles, Stuart↗
NASA NTRS1992

General Electric/Pratt and Whitney summary report

The views of GE and P&W on the High Speed Civil Transport (HSCT) are presented in viewgraph format. The technology developments needed to address the environmental issues of airport noise and engine emissions represent the threshold level for a viable program. These technologies must be introduced in concert with the propulsion system materials technologies and other aircraft technologies to reduce both the cost of ownership and the direct operating cost of the HSCT. They are key to the environmental compatibility and economic viability of a HSCT for entry into service in the year 2005.

Gilkey, Samuel C.↗
NASA NTRS1999

Application of Reconfigurable Avionics for the Bantam Launch Vehicle

The modern market is placing increasing pressure on launch costs. This is particularly true for small university science payloads, where the cost of the experiment itself is relatively low, and the launch frequency is potentially very high. It is the stated goal of the Bantam Program to dramatically reduce the costs of launching this class of payloads. This is a goal that will require that the avionics not only be reduced in production costs, but also in maintenance and operation costs, because the Bantam vehicle is envisioned as a reusable launch system. However, the costs of avionics is a relatively small fraction of the overall cost of launching a payload, and a simple reduction in the avionics costs will not immediately realize the necessary gains. Instead, to reduce the total system launch costs, it is also necessary to improve avionics performance. Only by reducing weight, volume, and power, while enhancing computational capability can the avionics be used to address the system-level cost reduction requirements. The National Aeronautics and Space Administration is currently pursuing technology development tasks, in order to support the Bantam requirements. One technology task is to develop a low-cost, high-performance reconfigurable avionics core unit. In addition to providing low cost and high performance, the use of reconfigurability will be used to explore the options of accommodating multiple launch configurations, and addressing such areas as redundancy management, single-event upset immunity, and low maintenance. This paper will address how emerging developments in reconfigurable avionics can be used to meet these challenges.

Wallace, Shawn↗
NASA NTRS1975

Study to evaluate the effect of EVA on payload systems. Volume 1: Executive summary

Programmatic benefits to payloads are examined which can result from the routine use of extravehicular activity (EVA) during space missions. Design and operations costs were compared for 13 representative baseline payloads to the costs of those payloads adapted for EVA operations. The EVA-oriented concepts developed in the study were derived from these baseline concepts and maintained mission and program objectives as well as basic configurations. This permitted isolation of cost saving factors associated specifically with incorporation of EVA in a variety of payload designs and operations. The study results were extrapolated to a total of 74 payload programs. Using appropriate complexity and learning factors, net EVA savings were extrapolated to over $551M for NASA and U.S. civil payloads for routine operations. Adding DOD and ESRO payloads increases the net estimated savings of $776M. Planned maintenance by EVA indicated an estimated $168M savings due to elimination of automated service equipment. Contingency problems of payloads were also analyzed to establish expected failure rates for shuttle payloads. The failure information resulted in an estimated potential for EVA savings of $1.9 B.

Patrick, J. W.↗
NASA NTRS2006

Comprehensive Environmental Informatics System (CEIS) Integrating Crew and Vehicle Environmental Health

Integrated Vehicle Health Management (IVHM) systems have been pursued as highly integrated systems that include smart sensors, diagnostic and prognostics software for assessments of real-time and life-cycle vehicle health information. Inclusive to such a system is the requirement to monitor the environmental health within the vehicle and the occupants of the vehicle. In this regard an enterprise approach to informatics is used to develop a methodology entitled, Comprehensive Environmental Informatics System (CEIS). The hardware and software technologies integrated into this system will be embedded in the vehicle subsystems, and maintenance operations, to provide both real-time and life-cycle health information of the environment within the vehicle cabin and of its occupants. This comprehensive information database will enable informed decision making and logistics management. One key element of the CEIS is interoperability for data acquisition and archive between environment and human system monitoring. With comprehensive components the data acquired in this system will use model based reasoning systems for subsystem and system level managers, advanced on-board and ground-based mission and maintenance planners to assess system functionality. Knowledge databases of the vehicle health state will be continuously updated and reported for critical failure modes, and routinely updated and reported for life cycle condition trending. Sufficient intelligence, including evidence-based engineering practices which are analogous to evidencebased medicine practices, will be included in the CEIS to result in more rapid recognition of off-nominal operation to enable quicker corrective actions. This will result from better information (rather than just data) for improved crew/operator situational awareness, which will produce significant vehicle and crew safety improvements, as well as increasing the chance for mission success, future mission planning as well as training. Other benefits include improved reliability, increase safety in operations and cost of operations. The cost benefits stem from significantly reduced processing and operations manpower, predictive maintenance for systems and subjects. The improvements in vehicle functionality and cost will result from increased prognostic and diagnostic capability due to the detailed total human exploration system health knowledge from CEIS. A collateral benefit is that there will be closer observations of the vehicle occupants as wrist watch sized devices are worn for continuous health monitoring. Additional database acquisition will stem from activities in countermeasure practices to ensure peak performance capability by occupants of the vehicle. The CEIS will provide data from advanced sensing technologies and informatics modeling which will be useful in problem troubleshooting, and improving NASA s awareness of systems during operation.

Nall, Mark E.↗
NASA NTRS2006

Cost Analysis for Large Civil Transport Rotorcraft

This paper presents cost analysis of purchase price and DOC+I (direct operating cost plus interest) that supports NASA s study of three advanced rotorcraft concepts that could enter commercial transport service within 10 to 15 years. The components of DOC+I are maintenance, flight crew, fuel, depreciation, insurance, and finance. The cost analysis aims at VTOL (vertical takeoff and landing) and CTOL (conventional takeoff and landing) aircraft suitable for regional transport service. The resulting spreadsheet-implemented cost models are semi-empirical and based on Department of Transportation and Army data from actual operations of such aircraft. This paper describes a rationale for selecting cost tech factors without which VTOL is more costly than CTOL by a factor of 10 for maintenance cost and a factor of two for purchase price. The three VTOL designs selected for cost comparisons meet the mission requirement to fly 1,200 nautical miles at 350 knots and 30,000 ft carrying 120 passengers. The lowest cost VTOL design is a large civil tilt rotor (LCTR) aircraft. With cost tech factors applied, the LCTR is reasonably competitive with the Boeing 737-700 when operated in economy regional service following the business model of the selected baseline operation, that of Southwest Airlines.

Coy, John J.↗
NASA NTRS2000

Operational Considerations when Designing New Ground Systems

The Hubble Space Telescope (HST) launched in April of 1991 with a nominal 15-year old mission. Since then, the HST mission life has been extended to 2010. As is true for all NASA missions, HST is being asked to decrease its operational costs for the remainder of its mission life. Various techniques are being incorporated for cost reductions, with one of the core means being the design of a new and more efficient ground system for HST operations. This new ground system, "Vision 2000", will reduce operational and maintenance costs and also provide the HST Project with added flexibility to react to future changes. Vision 2000 began supporting HST Operations in January of 1999 and will support the mission for the remainder of the mission life. Upgrading a satellite's ground system is a popular approach for reducing costs, but it is also inherently risky. Validating a new ground system can be a severe distraction to a flight team while operating a satellite. Mission data collection and health and safety requirements are rarely, if ever, relaxed during this validation period, forcing flight teams to undertake an additional task while operating the satellite. Additionally, flight teams must usually undergo extensive training to effectively utilize the new system. Once again, this training usually occurs as an additional task, in addition to the nominal satellite operations. While operating the spacecraft, the Flight Team typically assists in the design, validation, and verification of a new ground system. This is a distraction and strain on the Flight Team, but the benefit of using the Flight Team in all phases of ground system development far outweigh the negative aspects. Finally, above the cost of the new system, the integration into the facility with the current control center system are resources and costs not normally taken into account in the design phase of the new system. In addition to the standard issues faced by a Project when upgrading its ground system, the HST Project also must continue to support Space Shuttle servicing missions, which occur approximately every two to three years. This paper will address many of the issues common to all missions when re-hosting ground systems, and those faced by the HST Project in particular.

Walyus, Keith↗
NASA NTRS2017

DSN Wide Area Network Architecture, Capacity and Performance

This paper discusses the architecture of the wide area network that connects key communications facilities within the National Aeronautic and Space Administration (NASA) Deep Space Network (DSN). Several considerations are given to the design of this wide area network to ensure a timely, reliable, and secure data delivery between the mission users and their spacecraft. The network star configuration simplifies data delivery to users and minimizes operational cost. The dual-path connections maximize the system reliability, with geographical diversity in data routing to avoid single point of failure. Data encryption enhances the protection of mission users’ data. The system bandwidth is determined by balancing the needs to minimize the operating bandwidth cost and to have sufficient bandwidth to be able to deliver data to all users within the required. The DSN uses a class base weighted fair queuing (CBWFQ) method in its data delivery. This scheme guarantees a minimum bandwidth to each class of users and allows users to also access any unused bandwidth by other groups. The paper will also show performance of system reliability and bandwidth margin.

Liao, Jason↗
NASA NTRS1975

Simulation of on-orbit maintenance cycle for LST

A maintenance simulation model of the Large Space Telescope has been developed to assess the operational cost sensitivity to system configuration options. The model lends itself to equipment-level selections for various subsystem alternatives. Maintenance decisions include considerations for LST spacecraft on-orbit service or retrieval. Tradeoffs are identified in terms of on-orbit maintenance for specific design concepts, with Space Shuttle revisit costs balanced against retrieval and ground-facility operations. Simulation output is in the form of computer plots of cost, availability, time to first maintenance, and a cost-effective Shuttle revisit frequency.

Donnelly, J. A.↗
NASA NTRS2003

Performance Evaluation of Electrochem's PEM Fuel Cell Power Plant for NASA's 2nd Generation Reusable Launch Vehicle

NASA's Next Generation Launch Technology (NGLT) program is being developed to meet national needs for civil and commercial space access with goals of reducing the launch costs, increasing the reliability, and reducing the maintenance and operating costs. To this end, NASA is considering an all- electric capability for NGLT vehicles requiring advanced electrical power generation technology at a nominal 20 kW level with peak power capabilities six times the nominal power. The proton exchange membrane (PEM) fuel cell has been identified as a viable candidate to supply this electrical power; however, several technology aspects need to be assessed. Electrochem, Inc., under contract to NASA, has developed a breadboard power generator to address these technical issues with the goal of maximizing the system reliability while minimizing the cost and system complexity. This breadboard generator operates with dry hydrogen and oxygen gas using eductors to recirculate the gases eliminating gas humidification and blowers from the system. Except for a coolant pump, the system design incorporates passive components allowing the fuel cell to readily follow a duty cycle profile and that may operate at high 6:1 peak power levels for 30 second durations. Performance data of the fuel cell stack along with system performance is presented to highlight the benefits of the fuel cell stack design and system design for NGLT vehicles.

Kimble, Michael C.↗
NASA NTRS1981

Opportunities for structural improvements for an advanced supersonic transport vehicle

The superplastically formed diffusion-bonded (SPF/DB) program has developed successfully and far enough to recommend that a major structural program to validate the weight and cost of SPF/DB sandwich titanium structure should be initiated. The NASA Langley study of wing and fuselage SPF/DB sandwich panels shows that this process is potentially structurally efficient. The Douglas SPF/DB expanded sandwich process that utilizes a welded core sheet that expands to face sheets proves to be very efficient. The theoretical weight optimization design charts for the wing and fuselage concepts were validated by small-scale tests. Mnay design applications were fabricated. Projecting the results of an SPF/DB sandwich airframe structure to a MDC AST design shows significant weight and cost savings. A 6 percent lower direct operating cost was calculated. A growth AST utilizing composites, metal matrices, and SPF/DB sandwich shows future promise for a post-1990 technology readiness. Titanium SPF/DB sandwich, compared to presently available aluminum structure, is superior for application to a Mach 2.2 supersonic transport.

Fischler, J. E.↗
NASA NTRS1993

Study of basic physical processes in liquid and solid rocket propulsion

A process model was developed to assess the suitability of new/modified technologies and subsystems for application to commercial launch vehicles. Suitability is measured in terms of cost, safety, and environmental impact. Cost is related to recurring production and operational cost per flight, amortization of non-recurring development costs, 'effective' cost of difference in payload capability, and the cost of unreliability. The process is also applicable for assessing technologies and subsystems for application to other launch vehicles. The process will enable a comprehensive systems engineering approach to assess the potential of technologies and subsystems for launch vehicle applications and to provide documentation of the results for application to technology planning for the future.

Monroe, Joseph W.↗
NASA NTRS2001

Increasing Density and Reducing Costs of Data Acquisition

There are a number of reasons why it is important to increase the density of data acquisition functions. Sensor fusion seeks to integrate large numbers of sensors into a decision network. Addition of health monitoring functions may incur additional sensor requirements. But at the same time, it is important to reduce the per-channel costs of data acquisition systems. Often the most significant cost is the management of data acquisition networks, which incurs substantial costs associated with transducer installation, configuration, calibration, and maintenance. Alternatives that lower the cost of the transducer system and reduce the data acquisition system channel count will directly impact initial system costs. Other techniques that affect maintenance and operating costs will contribute to reducing life cycle costs. This paper describes work undertaken to explore alternative architectures for lowering the cost per transducer function using a MEMS-based accelerometer as the model.

Schmalzel, J. L.↗
NASA NTRS2006

A New Heavy-Lift Capability for Space Exploration: NASA's Ares V Cargo Launch Vehicle

The National Aeronautics and Space Administration (NASA) is developing new launch systems in preparation for the retirement of the Space Shuttle by 2010, as directed in the United States (U.S.) Vision for Space Exploration. The Ares I Crew Launch Vehicle (CLV) and the Ares V heavy-lift Cargo Launch Vehicle (CaLV) systems will build upon proven, reliable hardware derived from the Apollo Saturn (1961 to 1975) and Space Shuttle (1972 to 2010) programs to deliver safe, reliable, affordable space transportation solutions. This approach leverages existing aerospace talent and a unique infrastructure, as well as the vast amount of legacy knowledge gained from almost a half-century of hard-won experience in the space enterprise. Beginning early next decade, the Ares I will launch the new Crew Exploration Vehicle (CEV) to the International Space Station (ISS) or to low-Earth orbit for trips to the Moon and, ultimately, Mars. Late next decade, the Ares V's Earth Departure Stage will carry larger payloads such as the lunar lander into orbit, and the Crew Exploration Vehicle will dock with it for missions to the Moon, where astronauts will explore new territories and conduct science and technology experiments. Both the Ares I and Ares V systems are being designed to support longer future trips to Mars. The Exploration Launch Projects Office, located at NASA's Marshall Space Flight Center, is designing, developing, testing, and evaluating both launch vehicle systems in partnership with other NASA Centers, Government agencies, and industry contractors. This paper provides top-level information regarding the genesis and evolution of the baseline configuration for the Ares V heavy-lift system. It also touches on risk-based management strategies, such as building on powerful hardware and promoting common features between the Ares I and Ares V systems to reduce technical, schedule, and cost risks, as well as development and operations costs. Finally, it gives a summary of several notable accomplishments over the past year, since the Exploration Launch Projects effort officially kicked off in October 2005, and looks ahead at work planned for 2007 and beyond.

Sumrall, John P.↗
NASA NTRS2007

A New Heavy-Lift Capability for Space Exploration: NASA's Ares V Cargo Launch Vehicle

The National Aeronautics and Space Administration (NASA) is developing new launch systems and preparing to retire the Space Shuttle by 2010, as directed in the United States (U.S.) Vision for Space Exploration. The Ares I Crew Launch Vehicle (CLV) and the Ares V heavy-lift Cargo Launch Vehicle (CaLV) systems will build upon proven, reliable hardware derived from the Apollo-Saturn and Space Shuttle programs to deliver safe, reliable, affordable space transportation solutions. This approach leverages existing aerospace talent and a unique infrastructure, as well as legacy knowledge gained from nearly 50 years' experience developing space hardware. Early next decade, the Ares I will launch the new Orion Crew Exploration Vehicle (CEV) to the International Space Station (ISS) or to low-Earth orbit for trips to the Moon and, ultimately, Mars. Late next decade, the Ares V's Earth Departure Stage will carry larger payloads such as the lunar lander into orbit, and the Crew Exploration Vehicle will dock with it for missions to the Moon, where astronauts will explore new territories and conduct science and technology experiments. Both Ares I and Ares V are being designed to support longer future trips to Mars. The Exploration Launch Projects Office is designing, developing, testing, and evaluating both launch vehicle systems in partnership with other NASA Centers, Government agencies, and industry contractors. This paper provides top-level information regarding the genesis and evolution of the baseline configuration for the Ares V heavy-lift system. It also discusses riskbased, management strategies, such as building on powerful hardware and promoting common features between the Ares I and Ares V systems to reduce technical, schedule, and cost risks, as well as development and operations costs. Finally, it summarizes several notable accomplishments since October 2005, when the Exploration Launch Projects effort officially kicked off, and looks ahead at work planned for 2007 and beyond.

Sumrall, John P.↗
NASA NTRS2015

Risk-Aware Planetary Rover Operation: Autonomous Terrain Classification and Path Planning

Identifying and avoiding terrain hazards (e.g., soft soil and pointy embedded rocks) are crucial for the safety of planetary rovers. This paper presents a newly developed groundbased Mars rover operation tool that mitigates risks from terrain by automatically identifying hazards on the terrain, evaluating their risks, and suggesting operators safe paths options that avoids potential risks while achieving specified goals. The tool will bring benefits to rover operations by reducing operation cost, by reducing cognitive load of rover operators, by preventing human errors, and most importantly, by significantly reducing the risk of the loss of rovers.

Ono, Masahiro↗
NASA NTRSDate not supplied

Evaluation of Initial and Mid-Term Air Traffic Procedures for Urban Air Mobility Operations

Urban air mobility (UAM) operations are expected to expand in scale over the next several years as novel aircraft types, including electric vertical takeoff and landing aircraft, are certified and begin operations. These new aircraft may increase safety, decrease noise, and lower operating costs compared with helicopters, allowing them to operate in ways existing aircraft do not. It is vital that these expanded operations are compatible with and do not disrupt existing operations or the air traffic management system. To study the ways in which scaled UAM operations can best integrate in the national airspace system, NASA and Joby Aviation partnered to conduct a high-fidelity air traffic controller-in-the-loop study. Building on air traffic procedures used to manage high tempo operations in other parts of the airspace, new procedures, routes, and communications protocols were developed and tested by retired controllers in NASA’s Future Flight Central tower simulation facility. In addition, new cooperative airspace constructs in the form of corridors were developed to understand their potential contributions to even greater scales of operation. The controllers managed traffic scenarios in the Dallas-Fort Worth and Dallas Love Field airports consisting of fleets of up to 100 UAM aircraft operating alongside traditional traffic . Metrics for air traffic controller workload, duration of communications, departure delays, and other measures of allowable aircraft throughput were collected. The analysis indicates that using today’s procedures for initial UAM operations under nominal conditions could enable up to 40 operations per hour to an airport’s central terminal area if that involved crossing a runway and up to 55operations per hour if reaching the central terminal did not involve crossing a runway. Operations at these tempos did not delay or otherwise interfere with simulated runway traffic and were rated acceptable by the air traffic controllers. The new corridor constructs dramatically lowered controller workload in certain circumstances, suggesting they may be effective in further increasing the allowable scale of operations.

Urban Air Mobility↗