Thermal design of a natural gas - diesel dual fuel turbocharged V18 engine for ship propulsion and power plant applications

NASA Astrophysics Data System (ADS)

Douvartzides, S.; Karmalis, I.

2016-11-01

A detailed method is presented on the thermal design of a natural gas - diesel dual fuel internal combustion engine. An 18 cylinder four stroke turbocharged engine is considered to operate at a maximum speed of 500 rpm for marine and power plant applications. Thermodynamic, heat transfer and fluid flow phenomena are mathematically analyzed to provide a real cycle analysis together with a complete set of calculated operation conditions, power characteristics and engine efficiencies. The method is found to provide results in close agreement to published data for the actual performance of similar engines such as V18 MAN 51/60DF.

Saturn Apollo Program

NASA Image and Video Library

1963-01-01

Smokeless flame juts from the diffuser of a unique vacuum chamber in which the upper stage rocket engine, the hydrogen fueled J-2, was tested at a simulated space altitude in excess of 60,000 feet. The smoke you see is actually steam. In operation, vacuum is established by injecting steam into the chamber and is maintained by the thrust of the engine firing through the diffuser. The engine was tested in this environment for start, stop, coast, restart, and full-duration operations. The chamber was located at Rocketdyne's Propulsion Field Laboratory, in the Santa Susana Mountains, near Canoga Park, California. The J-2 engine was developed by Rocketdyne for the Marshall Space Flight Center.

Dynamic Simulation of a Wave Rotor Topped Turboshaft Engine

NASA Technical Reports Server (NTRS)

Greendyke, R. B.; Paxson, D. E.; Schobeiri, M. T.

1997-01-01

The dynamic behavior of a wave rotor topped turboshaft engine is examined using a numerical simulation. The simulation utilizes an explicit, one-dimensional, multi-passage, CFD based wave rotor code in combination with an implicit, one-dimensional, component level dynamic engine simulation code. Transient responses to rapid fuel flow rate changes and compressor inlet pressure changes are simulated and compared with those of a similarly sized, untopped, turboshaft engine. Results indicate that the wave rotor topped engine responds in a stable, and rapid manner. Furthermore, during certain transient operations, the wave rotor actually tends to enhance engine stability. In particular, there is no tendency toward surge in the compressor of the wave rotor topped engine during rapid acceleration. In fact, the compressor actually moves slightly away from the surge line during this transient. This behavior is precisely the opposite to that of an untopped engine. The simulation is described. Issues associated with integrating CFD and component level codes are discussed. Results from several transient simulations are presented and discussed.

The 2003 Goddard Rocket Replica Project: A Reconstruction of the World's First Functional Liquid Rocket System

NASA Technical Reports Server (NTRS)

Farr, R. A.; Elam, S. K.; Hicks, G. D.; Sanders, T. M.; London, J. R.; Mayne, A. W.; Christensen, D. L.

2003-01-01

As a part of NASA s 2003 Centennial of Flight celebration, engineers and technicians at Marshall Space Flight Center (MSFC), Huntsville, Alabama, in cooperation with the Alabama-Mississippi AIAA Section, have reconstructed historically accurate, functional replicas of Dr. Robert H. Goddard s 1926 first liquid- fuel rocket. The purposes of this project were to clearly understand, recreate, and document the mechanisms and workings of the 1926 rocket for exhibit and educational use, creating a vital resource for researchers studying the evolution of liquid rocketry for years to come. The MSFC team s reverse engineering activity has created detailed engineering-quality drawings and specifications describing the original rocket and how it was built, tested, and operated. Static hot-fire tests, as well as flight demonstrations, have further defined and quantified the actual performance and engineering actual performance and engineering challenges of this major segment in early aerospace history.

The quest for better quality-of-life - learning from large-scale shaking table tests

NASA Astrophysics Data System (ADS)

Nakashima, M.; Sato, E.; Nagae, T.; Kunio, F.; Takahito, I.

2010-12-01

Earthquake engineering has its origins in the practice of “learning from actual earthquakes and earthquake damages.” That is, we recognize serious problems by witnessing the actual damage to our structures, and then we develop and apply engineering solutions to solve these problems. This tradition in earthquake engineering, i.e., “learning from actual damage,” was an obvious engineering response to earthquakes and arose naturally as a practice in a civil and building engineering discipline that traditionally places more emphasis on experience than do other engineering disciplines. But with the rapid progress of urbanization, as society becomes denser, and as the many components that form our society interact with increasing complexity, the potential damage with which earthquakes threaten the society also increases. In such an era, the approach of ”learning from actual earthquake damages” becomes unacceptably dangerous and expensive. Among the practical alternatives to the old practice is to “learn from quasi-actual earthquake damages.” One tool for experiencing earthquake damages without attendant catastrophe is the large shaking table. E-Defense, the largest one we have, was developed in Japan after the 1995 Hyogoken-Nanbu (Kobe) earthquake. Since its inauguration in 2005, E-Defense has conducted over forty full-scale or large-scale shaking table tests, applied to a variety of structural systems. The tests supply detailed data on actual behavior and collapse of the tested structures, offering the earthquake engineering community opportunities to experience and assess the actual seismic performance of the structures, and to help society prepare for earthquakes. Notably, the data were obtained without having to wait for the aftermaths of actual earthquakes. Earthquake engineering has always been about life safety, but in recent years maintaining the quality of life has also become a critical issue. Quality-of-life concerns include nonstructural damage, business continuity, public health, quickness of damage assessment, infrastructure, data and communication networks, and other issues, and not enough useful empirical data have emerged about these issues from the experiences of actual earthquakes. To provide quantitative data that can be used to reduce earthquake risk to our quality of life, E-Defense recently has been implementing two comprehensive research projects in which a base-isolated hospital and a steel high-rise building were tested using the E-Defense shaking table and their seismic performance were examined particularly in terms of the nonstructural damage, damage to building contents and furniture, and operability, functionality, and business-continuity capability. The paper presents the overview of the two projects, together with major findings obtained from the projects.

RL10 ignition limits test for Shuttle Centaur

NASA Technical Reports Server (NTRS)

1987-01-01

During routine development testing of the RL10A-3-3B engine a potential no-ignition condition was encountered when operating at certain propellant inlet conditions within the Shuttle Centaur G operating region. The conditions, the resulting investigative program, and methods to correct the potential problem are discussed. The Shuttle Centaur program was cancelled prior to completion of this effort. Although the RL10 engine in the Atlas Centaur vehicle is required by specification to operate over a wide range of propellant inlet conditions. The vehicle actually operates over a narrow range of conditions. This factor, combined with configuration differences between Atlas Centaur (or Titan Centaur) and the Shuttle Centaur RL10 engines, indicates the ignition problem does not exist for these vehicles. As a precautionary measure the vehicle manufacturer was requested to coordinate with Pratt and Whitney any anticipated changes in propellant inlet conditions from the current narrow range. An engineering change will be proposed for future RL10 deliveries to provide more consistent propellant flow to the igniter. This will permit operation of the engine throughout the wide range specification inlet conditions if desired.

Confirmation of heavy metal ions in used lubricating oil from a passenger car using chelating self-assembled monolayer.

PubMed

Ko, Young Gun; Kim, Choong Hyun

2006-09-01

In order to prevent engine failure, the oil must be changed before it loses its protective properties. It is necessary to monitor the actual physical and chemical condition of the oil to reliably determine the optimum oil-change interval. Our study focuses on the condition of the lubricating oil in an operated car engine. Shear stress curves and viscosity curves as a function of the shear rate for fresh and used lubricating oil were examined. Metal nitrate was detected in the lubricating oil from the operated car engine through the use of a chelating self-assembled monolayer.

Dynamic Performance of High Bypass Ratio Turbine Engines With Water Ingestion

NASA Technical Reports Server (NTRS)

Murthy, S. N. B.

1996-01-01

The research on dynamic performance of high bypass turbofan engines includes studies on inlets, turbomachinery and the total engine system operating with air-water mixture; the water may be in vapor, droplet, or film form, and their combinations. Prediction codes (WISGS, WINCOF, WINCOF-1, WINCLR, and Transient Engine Performance Code) for performance changes, as well as changes in blade-casing clearance, have been established and demonstrated in application to actual, generic engines. In view of the continuous changes in water distribution in turbomachinery, the performance of both components and the total engine system must be determined in a time-dependent mode; hence, the determination of clearance changes also requires a time-dependent approach. In general, the performance and clearances changes cannot be scaled either with respect to operating or ingestion conditions. Removal of water prior to phase change is the most effective means of avoiding ingestion effects. Sufficient background has been established to perform definitive, full scale tests on a set of components and a complete engine to establish engine control and operability with various air-water vapor-water mixtures.

Analysis of unregulated emissions from an off-road diesel engine during realistic work operations

NASA Astrophysics Data System (ADS)

Lindgren, Magnus; Arrhenius, Karine; Larsson, Gunnar; Bäfver, Linda; Arvidsson, Hans; Wetterberg, Christian; Hansson, Per-Anders; Rosell, Lars

2011-09-01

Emissions from vehicle diesel engines constitute a considerable share of anthropogenic emissions of pollutants, including many non-regulated compounds such as aromatic hydrocarbons and alkenes. One way to reduce these emissions might be to use fuels with low concentrations of aromatic hydrocarbons, such as Fischer-Tropsch (F-T) diesels. Therefore this study compared Swedish Environmental Class 1 diesel (EC1) with the F-T diesel fuel Ecopar™ in terms of emissions under varied conditions (steady state, controlled transients and realistic work operations) in order to identify factors influencing emissions in actual operation. Using F-T diesel reduced emissions of aromatic hydrocarbons, but not alkenes. Emissions were equally dependent on work operation character (load, engine speed, occurrence of transients) for both fuels. There were indications that the emissions originated from unburnt fuel, rather than from combustion products.

Dynamic Characteristics and Stability Analysis of Space Shuttle Main Engine Oxygen Pump

NASA Technical Reports Server (NTRS)

Gunter, Edgar J.; Branagan, Lyle

1991-01-01

The dynamic characteristics of the Space Shuttle high pressure oxygen pump are presented. Experimental data is presented to show the vibration spectrum and response under actual engine operation and also in spin pit testing for balancing. The oxygen pump appears to be operating near a second critical speed and is sensitive to self excited aerodynamic cross coupling forces in the turbine and pump. An analysis is presented to show the improvement in pump stability by the application of turbulent flow seals, preburner seals, and pump shaft cross sectional modifications.

Mission Engineering of a Rapid Cycle Spacecraft Logistics Fleet

NASA Technical Reports Server (NTRS)

Holladay, Jon; McClendon, Randy (Technical Monitor)

2002-01-01

The requirement for logistics re-supply of the International Space Station has provided a unique opportunity for engineering the implementation of NASA's first dedicated pressurized logistics carrier fleet. The NASA fleet is comprised of three Multi-Purpose Logistics Modules (MPLM) provided to NASA by the Italian Space Agency in return for operations time aboard the International Space Station. Marshall Space Flight Center was responsible for oversight of the hardware development from preliminary design through acceptance of the third flight unit, and currently manages the flight hardware sustaining engineering and mission engineering activities. The actual MPLM Mission began prior to NASA acceptance of the first flight unit in 1999 and will continue until the de-commission of the International Space Station that is planned for 20xx. Mission engineering of the MPLM program requires a broad focus on three distinct yet inter-related operations processes: pre-flight, flight operations, and post-flight turn-around. Within each primary area exist several complex subsets of distinct and inter-related activities. Pre-flight processing includes the evaluation of carrier hardware readiness for space flight. This includes integration of payload into the carrier, integration of the carrier into the launch vehicle, and integration of the carrier onto the orbital platform. Flight operations include the actual carrier operations during flight and any required real-time ground support. Post-flight processing includes de-integration of the carrier hardware from the launch vehicle, de-integration of the payload, and preparation for returning the carrier to pre-flight staging. Typical space operations are engineered around the requirements and objectives of a dedicated mission on a dedicated operational platform (i.e. Launch or Orbiting Vehicle). The MPLM, however, has expanded this envelope by requiring operations with both vehicles during flight as well as pre-launch and post-landing operations. These unique requirements combined with a success-oriented schedule of four flights within a ten-month period have provided numerous opportunities for understanding and improving operations processes. Furthermore, it has increased the knowledge base of future Payload Carrier and Launch Vehicle hardware and requirement developments. Discussion of the process flows and target areas for process improvement are provided in the subject paper. Special emphasis is also placed on supplying guidelines for hardware development. The combination of process knowledge and hardware development knowledge will provide a comprehensive overview for future vehicle developments as related to integration and transportation of payloads.

Reusability aspects for space transportation rocket engines: programmatic status and outlook

NASA Astrophysics Data System (ADS)

Preclik, D.; Strunz, R.; Hagemann, G.; Langel, G.

2011-09-01

Rocket propulsion systems belong to the most critical subsystems of a space launch vehicle, being illustrated in this paper by comparing different types of transportation systems. The aspect of reusability is firstly discussed for the space shuttle main engine, the only rocket engine in the world that has demonstrated multiple reuses. Initial projections are contrasted against final reusability achievements summarizing three decades of operating the space shuttle main engine. The discussion is then extended to engines employed on expendable launch vehicles with an operational life requirement typically specifying structural integrities up to 20 cycles (start-ups) and an accumulated burning time of about 6,000 s (Vulcain engine family). Today, this life potential substantially exceeds the duty cycle of an expendable engine. It is actually exploited only during the development and qualification phase of an engine when system reliability is demonstrated on ground test facilities with a reduced number of hardware sets that are subjected to an extended number of test cycles and operation time. The paper will finally evaluate the logic and effort necessary to qualify a reusable engine for a required reliability and put this result in context of possible cost savings realized from reuse operations over a time span of 25 years.

A Risk Assessment Architecture for Enhanced Engine Operation

NASA Technical Reports Server (NTRS)

Litt, Jonathan S.; Sharp. Lauren M.; Guo, Ten-Huei

2010-01-01

On very rare occasions, in-flight emergencies have occurred that required the pilot to utilize the aircraft's capabilities to the fullest extent possible, sometimes using actuators in ways for which they were not intended. For instance, when flight control has been lost due to damage to the hydraulic systems, pilots have had to use engine thrust to maneuver the plane to the ground and in for a landing. To assist the pilot in these situations, research is being performed to enhance the engine operation by making it more responsive or able to generate more thrust. Enabled by modification of the propulsion control, enhanced engine operation can increase the probability of a safe landing during an inflight emergency. However, enhanced engine operation introduces risk as the nominal control limits, such as those on shaft speed, temperature, and acceleration, are exceeded. Therefore, an on-line tool for quantifying this risk must be developed to ensure that the use of an enhanced control mode does not actually increase the overall danger to the aircraft. This paper describes an architecture for the implementation of this tool. It describes the type of data and algorithms required and the information flow, and how the risk based on engine component lifing and operability for enhanced operation is determined.

Improving Team Performance: Proceedings of the Rand Team Performance Workshop.

DTIC Science & Technology

1980-08-01

organization theory, small group processes, cognitive psychologi training and instruction , decision theory, artificial intelligence, and human engineering...theory, small group processes, cognitive psy- chology, training and instruction , heuristic modeling, decision theory, and human engineering. Within...interact with. The operators are taught about the equipment and how it works; the actual job is left to be learned aboard ship. The cognitive processes the

ENGINEERING BULLETIN: PYROLYSIS TREATMENT

EPA Science Inventory

Pyrolysis is formally defined as chemical decomposition induced in organic materials by heat in the absence of oxygen. In practice, it is not possible to achieve a completely oxygen-free atmosphere; actual pyrolytic systems are operated with less than stoichiometric quantities of...

Healdsburg High School's Course on the Automobile.

ERIC Educational Resources Information Center

Attwood, Philip B.

1995-01-01

Reprints an article originally published in 1937. Discusses the need for some kind of training in automobile safety. Discusses an eight-week high school course on the automobile that covers engine operation, safety, auxiliary systems, and actual driving practice. (RS)

Alloy chemistry and microstructural control to meet the demands of the automotive Stirling engine

NASA Technical Reports Server (NTRS)

Stephens, Joseph R.

1988-01-01

The automotive Stirling engine now under development by DOE/NASA as an alternative to the internal combustion engine, imposes severe materials requirements for the hot portion of the engine. Materials selected must be low cost and contain a minimum of strategic elements so that availability is not a problem. Heater head tubes contain high pressure hydrogen on the inside and are exposed to hot combustion gases on the outside surface. The cylinders and regenerator housings must be readily castable into complex shapes having varying wall thicknesses and be amenable to brazing and welding operations. Also, high strength, oxidation resistance, resistance to hydrogen permeation, cyclic operation, and long-life are required. A research program conducted by NASA Lewis focused on alloy chemistry and microstructural control to achieve the desired properties over the life of the engine. Results of alloy selection, characterization, evaluation, and actual engine testing of selected materials are presented.

Alloy chemistry and microstructural control to meet the demands of the automotive Stirling engine

NASA Technical Reports Server (NTRS)

Stephens, J. R.

1986-01-01

The automotive Stirling engine now under development by DOE/NASA as an alternative to the internal combustion engine, imposes severe materials requirements for the hot portion of the engine. Materials selected must be low cost and contain a minimum of strategic elements so that availability is not a problem. Heater head tubes contain high pressure hydrogen on the inside and are exposed to hot combustion gases on the outside surface. The cylinders and regenerator housings must be readily castable into complex shapes having varying wall thicknesses and be amenable to brazing and welding operations. Also, high strength, oxidation resistance, resistance to hydrogen permeation, cyclic operation, and long-life are required. A research program conducted by NASA Lewis focused on alloy chemistry and microstructural control to achieve the desired properties over the life of the engine. Results of alloy selection, characterization, evaluation, and actual engine testing of selected materials are presented.

Preliminary Performance Data on Westinghouse Electronic Power Regulator Operating on J34-WE-32 Turbojet Engine in Altitude Wind Tunnel

NASA Technical Reports Server (NTRS)

Ketchum, James R.; Blivas, Darnold; Pack, George J.

1950-01-01

The behavior of the Westinghouse electronic power regulator operating on a J34-WE-32 turbojet engine was investigated in the NACA Lewis altitude wind tunnel at the request of the Bureau of Aeronautics, Department of the Navy. The object of the program was to determine the, steady-state stability and transient characteristics of the engine under control at various altitudes and ram pressure ratios, without afterburning. Recordings of the response of the following parameters to step changes in power lever position throughout the available operating range of the engine were obtained; ram pressure ratio, compressor-discharge pressure, exhaust-nozzle area, engine speed, turbine-outlet temperature, fuel-valve position, jet thrust, air flow, turbine-discharge pressure, fuel flow, throttle position, and boost-pump pressure. Representative preliminary data showing the actual time response of these variables are presented. These data are presented in the form of reproductions of oscillographic traces.

Building information modelling review with potential applications in tunnel engineering of China.

PubMed

Zhou, Weihong; Qin, Haiyang; Qiu, Junling; Fan, Haobo; Lai, Jinxing; Wang, Ke; Wang, Lixin

2017-08-01

Building information modelling (BIM) can be applied to tunnel engineering to address a number of problems, including complex structure, extensive design, long construction cycle and increased security risks. To promote the development of tunnel engineering in China, this paper combines actual cases, including the Xingu mountain tunnel and the Shigu Mountain tunnel, to systematically analyse BIM applications in tunnel engineering in China. The results indicate that BIM technology in tunnel engineering is currently mainly applied during the design stage rather than during construction and operation stages. The application of BIM technology in tunnel engineering covers many problems, such as a lack of standards, incompatibility of different software, disorganized management, complex combination with GIS (Geographic Information System), low utilization rate and poor awareness. In this study, through summary of related research results and engineering cases, suggestions are introduced and an outlook for the BIM application in tunnel engineering in China is presented, which provides guidance for design optimization, construction standards and later operation maintenance.

Building information modelling review with potential applications in tunnel engineering of China

PubMed Central

Zhou, Weihong; Qin, Haiyang; Fan, Haobo; Lai, Jinxing; Wang, Ke; Wang, Lixin

2017-01-01

Building information modelling (BIM) can be applied to tunnel engineering to address a number of problems, including complex structure, extensive design, long construction cycle and increased security risks. To promote the development of tunnel engineering in China, this paper combines actual cases, including the Xingu mountain tunnel and the Shigu Mountain tunnel, to systematically analyse BIM applications in tunnel engineering in China. The results indicate that BIM technology in tunnel engineering is currently mainly applied during the design stage rather than during construction and operation stages. The application of BIM technology in tunnel engineering covers many problems, such as a lack of standards, incompatibility of different software, disorganized management, complex combination with GIS (Geographic Information System), low utilization rate and poor awareness. In this study, through summary of related research results and engineering cases, suggestions are introduced and an outlook for the BIM application in tunnel engineering in China is presented, which provides guidance for design optimization, construction standards and later operation maintenance. PMID:28878970

Building information modelling review with potential applications in tunnel engineering of China

NASA Astrophysics Data System (ADS)

Zhou, Weihong; Qin, Haiyang; Qiu, Junling; Fan, Haobo; Lai, Jinxing; Wang, Ke; Wang, Lixin

2017-08-01

Building information modelling (BIM) can be applied to tunnel engineering to address a number of problems, including complex structure, extensive design, long construction cycle and increased security risks. To promote the development of tunnel engineering in China, this paper combines actual cases, including the Xingu mountain tunnel and the Shigu Mountain tunnel, to systematically analyse BIM applications in tunnel engineering in China. The results indicate that BIM technology in tunnel engineering is currently mainly applied during the design stage rather than during construction and operation stages. The application of BIM technology in tunnel engineering covers many problems, such as a lack of standards, incompatibility of different software, disorganized management, complex combination with GIS (Geographic Information System), low utilization rate and poor awareness. In this study, through summary of related research results and engineering cases, suggestions are introduced and an outlook for the BIM application in tunnel engineering in China is presented, which provides guidance for design optimization, construction standards and later operation maintenance.

Robust operative diagnosis as problem solving in a hypothesis space

NASA Technical Reports Server (NTRS)

Abbott, Kathy H.

1988-01-01

This paper describes an approach that formulates diagnosis of physical systems in operation as problem solving in a hypothesis space. Such a formulation increases robustness by: (1) incremental hypotheses construction via dynamic inputs, (2) reasoning at a higher level of abstraction to construct hypotheses, and (3) partitioning the space by grouping fault hypotheses according to the type of physical system representation and problem solving techniques used in their construction. It was implemented for a turbofan engine and hydraulic subsystem. Evaluation of the implementation on eight actual aircraft accident cases involving engine faults provided very promising results.

Evaluation of advanced displays for engine monitoring and control

NASA Technical Reports Server (NTRS)

Summers, L. G.

1993-01-01

The relative effectiveness of two advanced display concepts for monitoring engine performance for commercial transport aircraft was studied. The concepts were the Engine Monitoring and Control System (EMACS) display developed by NASA Langley and a display by exception design. Both of these concepts were based on the philosophy of providing information that is directly related to the pilot's task. Both concepts used a normalized thrust display. In addition, EMACS used column deviation indicators; i.e., the difference between the actual parameter value and the value predicted by an engine model, for engine health monitoring; while the Display by Exception displayed the engine parameters if the automated system detected a difference between the actual and the predicted values. The results showed that the advanced display concepts had shorter detection and response times. There were no differences in any of the results between manual and auto throttles. There were no effects upon perceived workload or performance on the primary flight task. The majority of pilots preferred the advanced displays and thought they were operationally acceptable. Certification of these concepts depends on the validation of the engine model. Recommendations are made to improve both the EMACS and the display by exception display formats.

Utilization of Variable Consumption Biofuel in Diesel Engine

NASA Astrophysics Data System (ADS)

Markov, V. A.; Kamaltdinov, V. G.; Savastenko, A. A.

2018-01-01

The depletion of oil fields and the deteriorating environmental situation leads to the need for the search of new alternative sources of energy. Actuality of the article due to the need for greater use of the alternative fuels in internal combustion engines is necessary. The advantages of vegetables origin fuels using as engine fuels are shown. Diesel engine operation on mixtures of petroleum diesel and rapeseed oil is researched. A fuel delivery system of mixture biofuel with a control system of the fuel compound is considered. The results of the system experimental researches of fuel delivery of mixture biofuel are led.

Recent California Water Transfers: Emerging Options in Water Management

DTIC Science & Technology

1992-12-01

geographically separated, requiring the use of conveyance and storage systems controlled by other parties. The controversies and complexities of effecting ...systematic examination of the engineering and operational aspects of water transfers. Instead, the mechanics of economically effecting actual water...drought and is now part of almost all California urban water plans and operations. The current drought also has had significant effects on how water

Requirements analysis notebook for the flight data systems definition in the Real-Time Systems Engineering Laboratory (RSEL)

NASA Astrophysics Data System (ADS)

Wray, Richard B.

1991-12-01

A hybrid requirements analysis methodology was developed, based on the practices actually used in developing a Space Generic Open Avionics Architecture. During the development of this avionics architecture, a method of analysis able to effectively define the requirements for this space avionics architecture was developed. In this methodology, external interfaces and relationships are defined, a static analysis resulting in a static avionics model was developed, operating concepts for simulating the requirements were put together, and a dynamic analysis of the execution needs for the dynamic model operation was planned. The systems engineering approach was used to perform a top down modified structured analysis of a generic space avionics system and to convert actual program results into generic requirements. CASE tools were used to model the analyzed system and automatically generate specifications describing the model's requirements. Lessons learned in the use of CASE tools, the architecture, and the design of the Space Generic Avionics model were established, and a methodology notebook was prepared for NASA. The weaknesses of standard real-time methodologies for practicing systems engineering, such as Structured Analysis and Object Oriented Analysis, were identified.

Requirements analysis notebook for the flight data systems definition in the Real-Time Systems Engineering Laboratory (RSEL)

NASA Technical Reports Server (NTRS)

Wray, Richard B.

1991-01-01

A hybrid requirements analysis methodology was developed, based on the practices actually used in developing a Space Generic Open Avionics Architecture. During the development of this avionics architecture, a method of analysis able to effectively define the requirements for this space avionics architecture was developed. In this methodology, external interfaces and relationships are defined, a static analysis resulting in a static avionics model was developed, operating concepts for simulating the requirements were put together, and a dynamic analysis of the execution needs for the dynamic model operation was planned. The systems engineering approach was used to perform a top down modified structured analysis of a generic space avionics system and to convert actual program results into generic requirements. CASE tools were used to model the analyzed system and automatically generate specifications describing the model's requirements. Lessons learned in the use of CASE tools, the architecture, and the design of the Space Generic Avionics model were established, and a methodology notebook was prepared for NASA. The weaknesses of standard real-time methodologies for practicing systems engineering, such as Structured Analysis and Object Oriented Analysis, were identified.

Three-Dimensional Measurements of Fuel Distribution in High-Pressure, High- Temperature, Next-Generation Aviation Gas Turbine Combustors

NASA Technical Reports Server (NTRS)

Hicks, Yolanda R.; Locke, Randy J.; Anderson, Robert C.; Zaller, Michelle M.

1998-01-01

In our world-class, optically accessible combustion facility at the NASA Lewis Research Center, we have developed the unique capability of making three-dimensional fuel distribution measurements of aviation gas turbine fuel injectors at actual operating conditions. These measurements are made in situ at the actual operating temperatures and pressures using the JP-grade fuels of candidate next-generation advanced aircraft engines for the High Speed Research (HSR) and Advanced Subsonics Technology (AST) programs. The inlet temperature and pressure ranges used thus far are 300 to 1100 F and 80 to 250 psia. With these data, we can obtain the injector spray angles, the fuel mass distributions of liquid and vapor, the degree of fuel vaporization, and the degree to which fuel has been consumed. The data have been used to diagnose the performance of injectors designed both in-house and by major U.S. engine manufacturers and to design new fuel injectors with overall engine performance goals of increased efficiency and reduced environmental impact. Mie scattering is used to visualize the liquid fuel, and laser-induced fluorescence is used to visualize both liquid and fuel vapor.

49 CFR 565.12 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... systems are to be part of the completed vehicle, that requires further manufacturing operations, other... applies to a group of vehicles or engines. (j) Manufacturer means a person— (1) Manufacturing or... calendar year in which the vehicle was actually produced, provided that the production period does not...

Benchmarking the Naval Systems Engineering Guide Against the Industry Standards for Systems Engineering

DTIC Science & Technology

2012-09-01

Maintenance activities, as this will allow new methods and Operational changes to be made if necessary (i.e., more downtime than originally planned or...increased complexity of military hardware, both new systems and their integration with legacy systems, requires a correspondingly increased expertise in...available Little of that added weight involves weapons or armor that actually is becoming lighter as new technologies and composites are utilized (Task

Army Officer Duty Module Manual.

DTIC Science & Technology

1975-10-01

14l 3( RELATIVE CRITICALITY OF THIS Not Least (2) (3) The most PART (MOOULE) TO ENTIRE JOB aplicable critical Average Critical critical a. In actual...3 Directs and controls operations of mobile communications O- support unit -36- I. - O-G-5 Establishes and controls mobile area signal center 0-6-6...ENGINEERING O-EE-1 Directs .and controls combat engineer unit O-EE-2 Directs and controls portable bridging O-EE-3 Directs and controls mobile water

Turbojet-engine Starting and Acceleration

NASA Technical Reports Server (NTRS)

Mc Cafferty, R. J.; Straight, D. M.

1956-01-01

From considerations of safety and reliability in performance of gas-turbine aircraft, it is clear that engine starting and acceleration are of utmost importance. For this reason extensive efforts have been devoted to the investigation of the factors involved in the starting and acceleration of engines. In chapter III it is shown that certain basic combustion requirements must be met before ignition can occur; consequently, the design and operation of an engine must be tailored to provide these basic requirements in the combustion zone of the engine, particularly in the vicinity of the ignition source. It is pointed out in chapter III that ignition by electrical discharges is aided by high pressure, high temperature, low gas velocity and turbulence, gaseous fuel-air mixture, proper mixture strength, and-an optimum spark. duration. The simultaneous achievement of all these requirements in an actual turbojet-engine combustor is obviously impossible, yet any attempt to satisfy as many requirements as possible will result in lower ignition energies, lower-weight ignition systems, and greater reliability. These factors together with size and cost considerations determine the acceptability of the final ignition system. It is further shown in chapter III that the problem of wall quenching affects engine starting. For example, the dimensions of the volume to be burned must be larger than the quenching distance at the lowest pressure and the most adverse fuel-air ratio encountered. This fact affects the design of cross-fire tubes between adjacent combustion chambers in a tubular-combustor turbojet engine. Only two chambers in these engines contain spark plugs; therefore, the flame must propagate through small connecting tubes between the chambers. The quenching studies indicate that if the cross-fire tubes are too narrow the flame will not propagate from one chamber to another. In order to better understand the role of the basic factors in actual engine operation, many investigations have been conducted in single combustors from gas-turbine engines and in full-scale engines in altitude tanks and in flight. The purpose of the present chapter is to discuss the results of such studies and, where possible, to interpret these results qualitatively in terms of the basic requirements reported in chapter III. The discussion parallels the three phases of turbojet engine starting: (1) Ignition of the fuel-air mixture (2) Propagation of flame throughout the combustion zone (3) Acceleration of the engine to operating speed.

Measurements of NOx emissions and in-service duty cycle from a towboat operating on the inland river system.

PubMed

Corbett, J J; Robinson, A L

2001-04-01

This paper describes measurements of NOx emissions from one engine on a commercial towboat operating on the Upper Ohio River system around the Port of Pittsburgh. Continuous measurements were made over a one-week period to characterize emissions during normal operations. The average NOx emission factor is 70 +/- 4.2 kg of NOx per t of fuel, similar to that of larger marine engines. A vessel-specific duty cycle is derived to characterize the towboat's operations; more than 50% of the time the vessel engines are at idle. Although recently promulgated EPA regulations apply only to new marine engines, these data provide insight into inland-river operations, which can be used to evaluate these regulations within the inland river context. This vessel operates as a courier service, scheduling pickups and deliveries of single- or multiple-barge loads per customers' requests; as many as 30% of the 277 towboats in the Pittsburgh region operate in this fashion. The EPA-prescribed ISO E3 duty cycle does not accurately describe inland-river operations of this towboat: its application overestimates actual NOx emissions by 14%. Only 41% of this vessel's operations fall within the Not-To-Exceed Zone defined by the EPA regulations, which limits the effectiveness of this component of the regulations to limit emissions from vessels that operate in a similar fashion.

Research on Correlation between Vehicle Cycle and Engine Cycle in Heavy-duty commercial vehicle

NASA Astrophysics Data System (ADS)

lin, Chen; Zhong, Wang; Shuai, Liu

2017-12-01

In order to study the correlation between vehicle cycle and engine cycle in heavy commercial vehicles, the conversion model of vehicle cycle to engine cycle is constructed based on the vehicle power system theory and shift strategy, which considers the verification on diesel truck. The results show that the model has high rationality and reliability in engine operation. In the acceleration process of high speed, the difference of model gear selection leads to the actual deviation. Compared with the drum test, the engine speed distribution obtained by the model deviates to right, which fits to the lower grade. The grade selection has high influence on the model.

Resilient Control and Intrusion Detection for SCADA Systems

DTIC Science & Technology

2014-05-01

Control. McGraw-Hill, 1996. [89] L. Greenemeier. Robots arrive at fukushima nuclear site with unclear mission. Scientific American, 2011. [90] M. Grimes...security engineering task. SCADA systems are hard real-time systems [251] because the completion of an operation after its deadline is considered useless and...that the attacker, after gaining unauthenticated access, could change the operator display values so that when an alarm actually goes off, the human

Modeling the emissions of a dual fuel engine coupled with a biomass gasifier-supplementing the Wiebe function.

PubMed

Vakalis, Stergios; Caligiuri, Carlo; Moustakas, Konstantinos; Malamis, Dimitris; Renzi, Massimiliano; Baratieri, Marco

2018-03-12

There is a growing market demand for small-scale biomass gasifiers that is driven by the economic incentives and the legislative framework. Small-scale gasifiers produce a gaseous fuel, commonly referred to as producer gas, with relatively low heating value. Thus, the most common energy conversion systems that are coupled with small-scale gasifiers are internal combustion engines. In order to increase the electrical efficiency, the operators choose dual fuel engines and mix the producer gas with diesel. The Wiebe function has been a valuable tool for assessing the efficiency of dual fuel internal combustion engines. This study introduces a thermodynamic model that works in parallel with the Wiebe function and calculates the emissions of the engines. This "vis-à-vis" approach takes into consideration the actual conditions inside the cylinders-as they are returned by the Wiebe function-and calculates the final thermodynamic equilibrium of the flue gases mixture. This approach aims to enhance the operation of the dual fuel internal combustion engines by identifying the optimal operating conditions and-at the same time-advance pollution control and minimize the environmental impact.

Miniaturization as a key factor to the development and application of advanced metrology systems

NASA Astrophysics Data System (ADS)

Furlong, Cosme; Dobrev, Ivo; Harrington, Ellery; Hefti, Peter; Khaleghi, Morteza

2012-10-01

Recent technological advances of miniaturization engineering are enabling the realization of components and systems with unprecedented capabilities. Such capabilities, which are significantly beneficial to scientific and engineering applications, are impacting the development and the application of optical metrology systems for investigations under complex boundary, loading, and operating conditions. In this paper, and overview of metrology systems that we are developing is presented. Systems are being developed and applied to high-speed and high-resolution measurements of shape and deformations under actual operating conditions for such applications as sustainability, health, medical diagnosis, security, and urban infrastructure. Systems take advantage of recent developments in light sources and modulators, detectors, microelectromechanical (MEMS) sensors and actuators, kinematic positioners, rapid prototyping fabrication technologies, as well as software engineering.

NASA's Robotics Mining Competition Provides Undergraduates Full Life Cycle Systems Engineering Experience

NASA Technical Reports Server (NTRS)

Stecklein, Jonette

2017-01-01

NASA has held an annual robotic mining competition for teams of university/college students since 2010. This competition is yearlong, suitable for a senior university engineering capstone project. It encompasses the full project life cycle from ideation of a robot design to actual tele-operation of the robot in simulated Mars conditions mining and collecting simulated regolith. A major required element for this competition is a Systems Engineering Paper in which each team describes the systems engineering approaches used on their project. The score for the Systems Engineering Paper contributes 25% towards the team's score for the competition's grand prize. The required use of systems engineering on the project by this competition introduces the students to an intense practical application of systems engineering throughout a full project life cycle.

PIV investigation of the flow induced by a passive surge control method in a radial compressor

NASA Astrophysics Data System (ADS)

Guillou, Erwann; Gancedo, Matthieu; Gutmark, Ephraim; Mohamed, Ashraf

2012-09-01

Due to recent emission regulations, the use of turbochargers for force induction of internal combustion engines has increased. Actually, the trend in diesel engines is to downsize the engine by use of turbochargers that operate at higher pressure ratios. Unfortunately, increasing the impeller rotational speed of turbocharger radial compressors tends to reduce their range of operation, which is limited at low mass flow rate by the occurrence of surge. In order to extend the operability of turbochargers, compressor housings can be equipped with a passive surge control device such as a "ported shroud." This specific casing treatment has been demonstrated to enhance the surge margin with minor negative impact on the compressor efficiency. However, the actual working mechanisms of the system remain not well understood. Hence, in order to optimize the design of the ported shroud, it is crucial to identify the dynamic flow changes induced by the implementation of the device to control instabilities. From the full dynamic survey of the compressor performance characteristics obtained with and without ported shroud, specific points of operation were selected to carry out planar flow visualization. At normal working, both standard and stereoscopic particle imaging velocimetry (PIV) measurements were performed to evaluate instantaneous and mean velocity flow fields at the inlet of the compressor. At incipient and full surge, phase-locked PIV measurements were added. As a result, satisfying characterization of the compressor instabilities was provided at different operational speeds. Combining transient pressure data and PIV measurements, the time evolution of the complex flow patterns occurring at surge was reconstructed and a better insight into the bypass mechanism was achieved.

Experimental and computational data from a small rocket exhaust diffuser

NASA Astrophysics Data System (ADS)

Stephens, Samuel E.

1993-06-01

The Diagnostics Testbed Facility (DTF) at the NASA Stennis Space Center in Mississippi is a versatile facility that is used primarily to aid in the development of nonintrusive diagnostics for liquid rocket engine testing. The DTF consists of a fixed, 1200 lbf thrust, pressure fed, liquid oxygen/gaseous hydrogen rocket engine, and associated support systems. An exhaust diffuser has been fabricated and installed to provide subatmospheric pressures at the exit of the engine. The diffuser aerodynamic design was calculated prior to fabrication using the PARC Navier-Stokes computational fluid dynamics code. The diffuser was then fabricated and tested at the DTF. Experimental data from these tests were acquired to determine the operational characteristics of the system and to correlate the actual and predicted flow fields. The results show that a good engineering approximation of overall diffuser performance can be made using the PARC Navier-Stokes code and a simplified geometry. Correlations between actual and predicted cell pressure and initial plume expansion in the diffuser are good; however, the wall pressure profiles do not correlate as well with the experimental data.

40 CFR 91.506 - Engine sample selection.

Code of Federal Regulations, 2010 CFR

2010-07-01

... paragraph (b)(2) of this section. It defines one-tail, 95 percent confidence intervals. σ=actual test sample... individual engine x=mean of emission test results of the actual sample FEL=Family Emission Limit n=The actual... carry-over engine families: After one engine is tested, the manufacturer will combine the test with the...

Identification of the actual state and entity availability forecasting in power engineering using neural-network technologies

NASA Astrophysics Data System (ADS)

Protalinsky, O. M.; Shcherbatov, I. A.; Stepanov, P. V.

2017-11-01

A growing number of severe accidents in RF call for the need to develop a system that could prevent emergency situations. In a number of cases accident rate is stipulated by careless inspections and neglects in developing repair programs. Across the country rates of accidents are growing because of a so-called “human factor”. In this regard, there has become urgent the problem of identification of the actual state of technological facilities in power engineering using data on engineering processes running and applying artificial intelligence methods. The present work comprises four model states of manufacturing equipment of engineering companies: defect, failure, preliminary situation, accident. Defect evaluation is carried out using both data from SCADA and ASEPCR and qualitative information (verbal assessments of experts in subject matter, photo- and video materials of surveys processed using pattern recognition methods in order to satisfy the requirements). Early identification of defects makes possible to predict the failure of manufacturing equipment using mathematical techniques of artificial neural network. In its turn, this helps to calculate predicted characteristics of reliability of engineering facilities using methods of reliability theory. Calculation of the given parameters provides the real-time estimation of remaining service life of manufacturing equipment for the whole operation period. The neural networks model allows evaluating possibility of failure of a piece of equipment consistent with types of actual defects and their previous reasons. The article presents the grounds for a choice of training and testing samples for the developed neural network, evaluates the adequacy of the neural networks model, and shows how the model can be used to forecast equipment failure. There have been carried out simulating experiments using a computer and retrospective samples of actual values for power engineering companies. The efficiency of the developed model for different types of manufacturing equipment has been proved. There have been offered other research areas in terms of the presented subject matter.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salnykov, A. A., E-mail: admin@rasnpp.org.ru

A method for predicting operating technological failures in nuclear power plants which makes it possible to reduce the unloading of the generator unit during the onset and development of an anomalous engineering state of the equipment by detecting a change in state earlier and taking suitable measures. With the circulating water supply loop of a nuclear power plant as an example, scenarios and algorithms for predicting technological failures in the operation of equipment long before their actual occurrence are discussed.

Integrated system design report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1989-07-01

The primary objective of the integrated system test phase is to demonstrate the commercial potential of a coal fueled diesel engine in its actual operating environment. The integrated system in this project is defined as a coal fueled diesel locomotive. This locomotive, shown on drawing 41D715542, is described in the separate Concept Design Report. The test locomotive will be converted from an existing oil fueled diesel locomotive in three stages, until it nearly emulates the concept locomotive. Design drawings of locomotive components (diesel engine, locomotive, flatcar, etc.) are included.

Engineering and Biology: Counsel for a Continued Relationship

PubMed Central

Levy, Arnon; Siegal, Mark L.; Soyer, Orkun S.; Wagner, Andreas

2015-01-01

Biologists frequently draw on ideas and terminology from engineering. Evolutionary systems biology—with its circuits, switches, and signal processing—is no exception. In parallel with the frequent links drawn between biology and engineering, there is ongoing criticism against this cross-fertilization, using the argument that over-simplistic metaphors from engineering are likely to mislead us as engineering is fundamentally different from biology. In this article, we clarify and reconfigure the link between biology and engineering, presenting it in a more favorable light. We do so by, first, arguing that critics operate with a narrow and incorrect notion of how engineering actually works, and of what the reliance on ideas from engineering entails. Second, we diagnose and diffuse one significant source of concern about appeals to engineering, namely that they are inherently and problematically metaphorical. We suggest that there is plenty of fertile ground left for a continued, healthy relationship between engineering and biology. PMID:26085824

Petroleum Diesel Fuel and Linseed Oil Mixtures as Engine Fuels

NASA Astrophysics Data System (ADS)

Markov, V. A.; Kamaltdinov, V. G.; Savastenko, A. A.

2018-01-01

The actual problem is the use of alternative biofuels in automotive diesel engines. Insufficiently studied are the indicators of toxicity of exhaust gases of these engines operating on biofuel. The aim of the study is to identify indicators of the toxicity of exhaust gases when using of petroleum diesel fuel and linseed oil mixtures as a fuel for automotive diesel engines. Physical and chemical properties of linseed oil and its mixtures with petroleum diesel fuel are considered. Experimental researches of D-245.12C diesel are carried out on mixtures of diesel fuel and corn oil with a different composition. An opportunity of exhaust toxicity indexes improvement using these mixtures as a fuel for automobiles engine is shown.

Unified trade-off optimization for general heat devices with nonisothermal processes.

PubMed

Long, Rui; Liu, Wei

2015-04-01

An analysis of the efficiency and coefficient of performance (COP) for general heat engines and refrigerators with nonisothermal processes is conducted under the trade-off criterion. The specific heat of the working medium has significant impacts on the optimal configurations of heat devices. For cycles with constant specific heat, the bounds of the efficiency and COP are found to be the same as those obtained through the endoreversible Carnot ones. However, they are independent of the cycle time durations. For cycles with nonconstant specific heat, whose dimensionless contact time approaches infinity, the general alternative upper and lower bounds of the efficiency and COP under the trade-off criteria have been proposed under the asymmetric limits. Furthermore, when the dimensionless contact time approaches zero, the endoreversible Carnot model is recovered. In addition, the efficiency and COP bounds of different kinds of actual heat engines and refrigerators have also been analyzed. This paper may provide practical insight for designing and operating actual heat engines and refrigerators.

Quantum dynamical framework for Brownian heat engines

NASA Astrophysics Data System (ADS)

Agarwal, G. S.; Chaturvedi, S.

2013-07-01

We present a self-contained formalism modeled after the Brownian motion of a quantum harmonic oscillator for describing the performance of microscopic Brownian heat engines such as Carnot, Stirling, and Otto engines. Our theory, besides reproducing the standard thermodynamics results in the steady state, enables us to study the role dissipation plays in determining the efficiency of Brownian heat engines under actual laboratory conditions. In particular, we analyze in detail the dynamics associated with decoupling a system in equilibrium with one bath and recoupling it to another bath and obtain exact analytical results, which are shown to have significant ramifications on the efficiencies of engines involving such a step. We also develop a simple yet powerful technique for computing corrections to the steady state results arising from finite operation time and use it to arrive at the thermodynamic complementarity relations for various operating conditions and also to compute the efficiencies of the three engines cited above at maximum power. Some of the methods and exactly solvable models presented here are interesting in their own right and could find useful applications in other contexts as well.

System Guidelines for EMC Safety-Critical Circuits: Design, Selection, and Margin Demonstration

NASA Technical Reports Server (NTRS)

Lawton, R. M.

1996-01-01

Demonstration of required safety margins on critical electrical/electronic circuits in large complex systems has become an implementation and cost problem. These margins are the difference between the activation level of the circuit and the electrical noise on the circuit in the actual operating environment. This document discusses the origin of the requirement and gives a detailed process flow for the identification of the system electromagnetic compatibility (EMC) critical circuit list. The process flow discusses the roles of engineering disciplines such as systems engineering, safety, and EMC. Design and analysis guidelines are provided to assist the designer in assuring the system design has a high probability of meeting the margin requirements. Examples of approaches used on actual programs (Skylab and Space Shuttle Solid Rocket Booster) are provided to show how variations of the approach can be used successfully.

Two-D results on human operator perception

NASA Technical Reports Server (NTRS)

Siapkara, A. A.; Sheridan, T. B.

1981-01-01

The application of multidimensional scaling methodology in human factors engineering is presented. The nonorthogonality of internally perceived task variables is exhibited for first and second order plants with both dependent and independent task variables. Directions of operator preference are shown for actual performance, pilot opinion rating, and subjective measures of fatigue, adaptability, and system recognition. Improvement of performance in second order systems is exhibited by the use of bang-bang feedback information. Dissimilarity measures for system comparison are suggested in order to account for human operator rotations and subjective sense of time.

Analysis of an Increase in the Efficiency of a Spark Ignition Engine Through the Application of an Automotive Thermoelectric Generator

NASA Astrophysics Data System (ADS)

Merkisz, Jerzy; Fuc, Pawel; Lijewski, Piotr; Ziolkowski, Andrzej; Galant, Marta; Siedlecki, Maciej

2016-08-01

We have analyzed the increase of the overall efficiency of a spark ignition engine through energy recovery following the application of an automotive thermoelectric generator (ATEG) of our own design. The design of the generator was developed following emission investigations during vehicle driving under city traffic conditions. The measurement points were defined by actual operation conditions (engine speed and load), subsequently reproduced on an engine dynamometer. Both the vehicle used in the on-road tests and the engine dynamometer were fit with the same, downsized spark ignition engine (with high effective power-to-displacement ratio). The thermodynamic parameters of the exhaust gases (temperature and exhaust gas mass flow) were measured on the engine testbed, along with the fuel consumption and electric current generated by the thermoelectric modules. On this basis, the power of the ATEG and its impact on overall engine efficiency were determined.

The traverse planning process for D-RATS 2010

NASA Astrophysics Data System (ADS)

Hörz, Friedrich; Lofgren, Gary E.; Gruener, John E.; Eppler, Dean B.; Skinner, James A.; Fortezzo, Corey M.; Graf, Jodi S.; Bluethmann, William J.; Seibert, Marc A.; Bell, Ernest R.

2013-10-01

This report describes the traverse planning process for the Desert Research and Technology Studies (D-RATS) 2010 field simulation of a conceptual 14-day planetary mission. This activity took place between August 23 and September 17, 2010 in the San Francisco Volcanic Field, Arizona. It focused on the utilization of two pressurized rovers and a ground-based communication system, as well as on the development of mission operation concepts for long duration, dual-rover missions. The early planning process began some 12 months prior to the actual field tests and defined the first order engineering-, flight operations, and science objectives. The detailed implementation and refinement of these objectives took place over the ensuing 10 months, resulting in a large number of technical and operational constraints that affected the actual traverse route or the cumulative Extravehicular Activity (EVA) time available for detailed field observations. The science planning proceeded from the generation of photogeologic maps of the test area, to the establishment of prioritized science objectives and associated candidate sites for detailed field exploration. The combination of operational constraints and science objectives resulted in the final design of traverse routes and time lines for each of the 24 traverses needed to support 12 field days by two rovers. Examples of daily traverses will be given that will hopefully illustrate that the design of long duration, long distance planetary traverses is a highly interdisciplinary and time-consuming collaboration between diverse engineers, flight operations personnel, human factors interests, and planetary scientists.

Re-Engineering the Mission Operations System (MOS) for the Prime and Extended Mission

NASA Technical Reports Server (NTRS)

Hunt, Joseph C., Jr.; Cheng, Leo Y.

2012-01-01

One of the most challenging tasks in a space science mission is designing the Mission Operations System (MOS). Whereas the focus of the project is getting the spacecraft built and tested for launch, the mission operations engineers must build a system to carry out the science objectives. The completed MOS design is then formally assessed in the many reviews. Once a mission has completed the reviews, the Mission Operation System (MOS) design has been validated to the Functional Requirements and is ready for operations. The design was built based on heritage processes, new technology, and lessons learned from past experience. Furthermore, our operational concepts must be properly mapped to the mission design and science objectives. However, during the course of implementing the science objective in the operations phase after launch, the MOS experiences an evolutional change to adapt for actual performance characteristics. This drives the re-engineering of the MOS, because the MOS includes the flight and ground segments. Using the Spitzer mission as an example we demonstrate how the MOS design evolved for both the prime and extended mission to enhance the overall efficiency for science return. In our re-engineering process, we ensured that no requirements were violated or mission objectives compromised. In most cases, optimized performance across the MOS, including gains in science return as well as savings in the budget profile was achieved. Finally, we suggest a need to better categorize the Operations Phase (Phase E) in the NASA Life-Cycle Phases of Formulation and Implementation

Man-vehicle systems research facility advanced aircraft flight simulator throttle mechanism

NASA Technical Reports Server (NTRS)

Kurasaki, S. S.; Vallotton, W. C.

1985-01-01

The Advanced Aircraft Flight Simulator is equipped with a motorized mechanism that simulates a two engine throttle control system that can be operated via a computer driven performance management system or manually by the pilots. The throttle control system incorporates features to simulate normal engine operations and thrust reverse and vary the force feel to meet a variety of research needs. While additional testing to integrate the work required is principally now in software design, since the mechanical aspects function correctly. The mechanism is an important part of the flight control system and provides the capability to conduct human factors research of flight crews with advanced aircraft systems under various flight conditions such as go arounds, coupled instrument flight rule approaches, normal and ground operations and emergencies that would or would not normally be experienced in actual flight.

An insight into actual energy use and its drivers in high-performance buildings

DOE PAGES

Li, Cheng; Hong, Tianzhen; Yan, Da

2014-07-12

Using portfolio analysis and individual detailed case studies, we studied the energy performance and drivers of energy use in 51 high-performance office buildings in the U.S., Europe, China, and other parts of Asia. Portfolio analyses revealed that actual site energy use intensity (EUI) of the study buildings varied by a factor of as much as 11, indicating significant variation in real energy use in HPBs worldwide. Nearly half of the buildings did not meet the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) Standard 90.1-2004 energy target, raising questions about whether a building’s certification as high performing accuratelymore » indicates that a building is energy efficient and suggesting that improvement in the design and operation of HPBs is needed to realize their energy-saving potential. We studied the influence of climate, building size, and building technologies on building energy performance and found that although all are important, none are decisive factors in building energy use. EUIs were widely scattered in all climate zones. There was a trend toward low energy use in small buildings, but the correlation was not absolute; some small HPBs exhibited high energy use, and some large HPBs exhibited low energy use. We were unable to identify a set of efficient technologies that correlated directly to low EUIs. In two case studies, we investigated the influence of occupant behavior as well as operation and maintenance on energy performance and found that both play significant roles in realizing energy savings. We conclude that no single factor determines the actual energy performance of HPBs, and adding multiple efficient technologies does not necessarily improve building energy performance; therefore, an integrated design approach that takes account of climate, technology, occupant behavior, and operations and maintenance practices should be implemented to maximize energy savings in HPBs. As a result, these findings are intended to help architects, engineers, operators, and policy makers improve the design and operation of HPBs.« less

Improving the Estimates of International Space Station (ISS) Induced K-Factor Failure Rates for On-Orbit Replacement Unit (ORU) Supportability Analyses

NASA Technical Reports Server (NTRS)

Anderson, Leif F.; Harrington, Sean P.; Omeke, Ojei, II; Schwaab, Douglas G.

2009-01-01

This is a case study on revised estimates of induced failure for International Space Station (ISS) on-orbit replacement units (ORUs). We devise a heuristic to leverage operational experience data by aggregating ORU, associated function (vehicle sub -system), and vehicle effective' k-factors using actual failure experience. With this input, we determine a significant failure threshold and minimize the difference between the actual and predicted failure rates. We conclude with a discussion on both qualitative and quantitative improvements the heuristic methods and potential benefits to ISS supportability engineering analysis.

Manufacturing implementation of off-line programming for the Space Shuttle Main Engines

NASA Technical Reports Server (NTRS)

Sliwinski, K. E.; Pierson, B. L.; Anderson, R. R.; Guthmiller, W. A.

1989-01-01

An account is given of the efforts made to implement an off-line programming (OLP) system for a gas tungsten arc welding robot in actual manufacturing operations, namely those involved in the manufacture of the SSMEs. In conjunction with a real-time sensor control system, the OLP constitutes the Advanced Robotic Welding System, or 'AROWS'. OLP's task is to develop a robot-motion path without the initial use of the robot to 'teach' the characteristics of such motion; actual process parameters are recorded by OLP and correlated with the position along the weld.

Virtually Out of This World!

NASA Technical Reports Server (NTRS)

2002-01-01

Ames Research Center granted Reality Capture Technologies (RCT), Inc., a license to further develop NASA's Mars Map software platform. The company incorporated NASA#s innovation into software that uses the Virtual Plant Model (VPM)(TM) to structure, modify, and implement the construction sites of industrial facilities, as well as develop, validate, and train operators on procedures. The VPM orchestrates the exchange of information between engineering, production, and business transaction systems. This enables users to simulate, control, and optimize work processes while increasing the reliability of critical business decisions. Engineers can complete the construction process and test various aspects of it in virtual reality before building the actual structure. With virtual access to and simulation of the construction site, project personnel can manage, access control, and respond to changes on complex constructions more effectively. Engineers can also create operating procedures, training, and documentation. Virtual Plant Model(TM) is a trademark of Reality Capture Technologies, Inc.

Model-based diagnosis of large diesel engines based on angular speed variations of the crankshaft

NASA Astrophysics Data System (ADS)

Desbazeille, M.; Randall, R. B.; Guillet, F.; El Badaoui, M.; Hoisnard, C.

2010-07-01

This work aims at monitoring large diesel engines by analyzing the crankshaft angular speed variations. It focuses on a powerful 20-cylinder diesel engine with crankshaft natural frequencies within the operating speed range. First, the angular speed variations are modeled at the crankshaft free end. This includes modeling both the crankshaft dynamical behavior and the excitation torques. As the engine is very large, the first crankshaft torsional modes are in the low frequency range. A model with the assumption of a flexible crankshaft is required. The excitation torques depend on the in-cylinder pressure curve. The latter is modeled with a phenomenological model. Mechanical and combustion parameters of the model are optimized with the help of actual data. Then, an automated diagnosis based on an artificially intelligent system is proposed. Neural networks are used for pattern recognition of the angular speed waveforms in normal and faulty conditions. Reference patterns required in the training phase are computed with the model, calibrated using a small number of actual measurements. Promising results are obtained. An experimental fuel leakage fault is successfully diagnosed, including detection and localization of the faulty cylinder, as well as the approximation of the fault severity.

Real-Time Simulation of the X-33 Aerospace Engine

NASA Technical Reports Server (NTRS)

Aguilar, Robert

1999-01-01

This paper discusses the development and performance of the X-33 Aerospike Engine RealTime Model. This model was developed for the purposes of control law development, six degree-of-freedom trajectory analysis, vehicle system integration testing, and hardware-in-the loop controller verification. The Real-Time Model uses time-step marching solution of non-linear differential equations representing the physical processes involved in the operation of a liquid propellant rocket engine, albeit in a simplified form. These processes include heat transfer, fluid dynamics, combustion, and turbomachine performance. Two engine models are typically employed in order to accurately model maneuvering and the powerpack-out condition where the power section of one engine is used to supply propellants to both engines if one engine malfunctions. The X-33 Real-Time Model is compared to actual hot fire test data and is been found to be in good agreement.

Application of State Analysis and Goal-based Operations to a MER Mission Scenario

NASA Technical Reports Server (NTRS)

Morris, John Richard; Ingham, Michel D.; Mishkin, Andrew H.; Rasmussen, Robert D.; Starbird, Thomas W.

2006-01-01

State Analysis is a model-based systems engineering methodology employing a rigorous discovery process which articulates operations concepts and operability needs as an integrated part of system design. The process produces requirements on system and software design in the form of explicit models which describe the system behavior in terms of state variables and the relationships among them. By applying State Analysis to an actual MER flight mission scenario, this study addresses the specific real world challenges of complex space operations and explores technologies that can be brought to bear on future missions. The paper first describes the tools currently used on a daily basis for MER operations planning and provides an in-depth description of the planning process, in the context of a Martian day's worth of rover engineering activities, resource modeling, flight rules, science observations, and more. It then describes how State Analysis allows for the specification of a corresponding goal-based sequence that accomplishes the same objectives, with several important additional benefits.

Application of State Analysis and Goal-Based Operations to a MER Mission Scenario

NASA Technical Reports Server (NTRS)

Morris, J. Richard; Ingham, Michel D.; Mishkin, Andrew H.; Rasmussen, Robert D.; Starbird, Thomas W.

2006-01-01

State Analysis is a model-based systems engineering methodology employing a rigorous discovery process which articulates operations concepts and operability needs as an integrated part of system design. The process produces requirements on system and software design in the form of explicit models which describe the behavior of states and the relationships among them. By applying State Analysis to an actual MER flight mission scenario, this study addresses the specific real world challenges of complex space operations and explores technologies that can be brought to bear on future missions. The paper describes the tools currently used on a daily basis for MER operations planning and provides an in-depth description of the planning process, in the context of a Martian day's worth of rover engineering activities, resource modeling, flight rules, science observations, and more. It then describes how State Analysis allows for the specification of a corresponding goal-based sequence that accomplishes the same objectives, with several important additional benefits.

Two-dimensional model studies of the effect of supersonic aircraft operations on the stratospheric ozone content

NASA Technical Reports Server (NTRS)

Whitten, R. C.; Borucki, W. J.; Poppoff, I. G.; Latt, L.; Widhopf, G. F.; Capone, L. A.; Reigel, C. A.

1981-01-01

For a fleet of 250 aircraft, the change in the ozone column is predicted to be very close to zero; in fact, the ozone overburden may actually increase as a result of show that above 25 to 30 km the ozone abundance decreases via catalytic destruction, but at lower heights it increases, mainly as a result of coupling with odd hydrogen species. Water vapor released in the engine exhaust is predicted to cause ozone decreases; for the hypothetical engines used in the study, the total column ozone changes due to water vapor emission largely offset the predicted ozone increases due to NOx emission. The actual effect of water vapor may be less than calculated because present models do not include thermal feedback. Feedback refers to the cooling effect of additional water vapor that would tend to slow the NOx reactions which destroy ozone.

Rise of the Functionals?: Mobility Air Force Developmental Teams and their Impact on Officer Education and Advancement

DTIC Science & Technology

2014-06-01

Specialists (43X/44X/45X) Chaplain (52R) Civil Engineer (32E) Combat Air Force Contracting (64P) Cyber Operations (17D) Dental (47X) Finance (65 F...assume the principal has a perfect decision making calculus . The MAF DT may actually have asymmetric information, and given the opportunity, they could

Engine Development Design Margins Briefing Charts

NASA Technical Reports Server (NTRS)

Bentz, Chuck

2006-01-01

New engines experience durability problems after entering service. The most prevalent and costly is the hot section, particularly the high-pressure turbine. The origin of durability problems can be traced back to: 1) the basic aero-mechanical design systems, assumptions, and design margins used by the engine designers, 2) the available materials systems, and 3) to a large extent, aggressive marketing in a highly competitive environment that pushes engine components beyond the demonstrated capability of the basic technology available for the hardware designs. Unfortunately the user must operate the engine in the service environment in order to learn the actual thrust loading and the time at max effort take-off conditions used in service are needed to determine the hot section life. Several hundred thousand hours of operational service will be required before the demonstrated reliability of a fleet of engines or the design deficiencies of the engine hot section parts can be determined. Also, it may take three to four engine shop visits for heavy maintenance on the gas path hardware to establish cost effective build standards. Spare parts drive the oerator's engine maintenance costs but spare parts also makes lots of money for the engine manufacturer during the service life of an engine. Unless competition prevails for follow-on engine buys, there is really no motivation for an OEM to spend internal money to improve parts durability and reduce earnings derived from a lucrative spare parts business. If the hot section life is below design goals or promised values, the OEM migh argue that the engine is being operated beyond its basic design intent. On the other hand, the airframer and the operator will continue to remind the OEM that his engine was selected based on a lot of promises to deliver spec thrust with little impact on engine service life if higher thrust is used intermittently. In the end, a standoff prevails and nothing gets fixed. This briefing will propose ways to hold competing engine manufacturers more accountable for engine hot section design margins during the entire Engine Development process as well as provide tools to assess the design temperature margins in the hot section parts of Service Engines.

On the energy efficiency of cyclic mechanisms

NASA Astrophysics Data System (ADS)

Briskin, E. S.; Kalinin, Ya. V.; Maloletov, A. V.; Chernyshev, V. V.

2014-01-01

We consider cyclic mechanisms with one degree of freedom driven by engines of various types such as alternating and direct current motors, internal combustion engines, etc. We pose the problem of modifying the mechanism structure by joining additional links or by varying the parameters or operation mode of the original mechanism so as to minimize the thermal losses in the driving motor. The solution is based on the minimization of the functional determining the irreversible power losses. We show that, for the engines considered, all cyclic mechanisms with one degree of freedom should satisfy a fundamental condition ensuring the minimum of losses. We consider two examples, one of which corresponds to actually existing mechanisms.

Thrust stand evaluation of engine performance improvement algorithms in an F-15 airplane

NASA Technical Reports Server (NTRS)

Conners, Timothy R.

1992-01-01

Results are presented from the evaluation of the performance seeking control (PSC) optimization algorithm developed by Smith et al. (1990) for F-15 aircraft, which optimizes the quasi-steady-state performance of an F100 derivative turbofan engine for several modes of operation. The PSC algorithm uses onboard software engine model that calculates thrust, stall margin, and other unmeasured variables for use in the optimization. Comparisons are presented between the load cell measurements, PSC onboard model thrust calculations, and posttest state variable model computations. Actual performance improvements using the PSC algorithm are presented for its various modes. The results of using PSC algorithm are compared with similar test case results using the HIDEC algorithm.

A proposed Kalman filter algorithm for estimation of unmeasured output variables for an F100 turbofan engine

NASA Technical Reports Server (NTRS)

Alag, Gurbux S.; Gilyard, Glenn B.

1990-01-01

To develop advanced control systems for optimizing aircraft engine performance, unmeasurable output variables must be estimated. The estimation has to be done in an uncertain environment and be adaptable to varying degrees of modeling errors and other variations in engine behavior over its operational life cycle. This paper represented an approach to estimate unmeasured output variables by explicitly modeling the effects of off-nominal engine behavior as biases on the measurable output variables. A state variable model accommodating off-nominal behavior is developed for the engine, and Kalman filter concepts are used to estimate the required variables. Results are presented from nonlinear engine simulation studies as well as the application of the estimation algorithm on actual flight data. The formulation presented has a wide range of application since it is not restricted or tailored to the particular application described.

Stimulation of a turbofan engine for evaluation of multivariable optimal control concepts. [(computerized simulation)

NASA Technical Reports Server (NTRS)

Seldner, K.

1976-01-01

The development of control systems for jet engines requires a real-time computer simulation. The simulation provides an effective tool for evaluating control concepts and problem areas prior to actual engine testing. The development and use of a real-time simulation of the Pratt and Whitney F100-PW100 turbofan engine is described. The simulation was used in a multi-variable optimal controls research program using linear quadratic regulator theory. The simulation is used to generate linear engine models at selected operating points and evaluate the control algorithm. To reduce the complexity of the design, it is desirable to reduce the order of the linear model. A technique to reduce the order of the model; is discussed. Selected results between high and low order models are compared. The LQR control algorithms can be programmed on digital computer. This computer will control the engine simulation over the desired flight envelope.

Research on Visualization Design Method in the Field of New Media Software Engineering

NASA Astrophysics Data System (ADS)

Deqiang, Hu

2018-03-01

In the new period of increasingly developed science and technology, with the increasingly fierce competition in the market and the increasing demand of the masses, new design and application methods have emerged in the field of new media software engineering, that is, the visualization design method. Applying the visualization design method to the field of new media software engineering can not only improve the actual operation efficiency of new media software engineering but more importantly the quality of software development can be enhanced by means of certain media of communication and transformation; on this basis, the progress and development of new media software engineering in China are also continuously promoted. Therefore, the application of visualization design method in the field of new media software engineering is analysed concretely in this article from the perspective of the overview of visualization design methods and on the basis of systematic analysis of the basic technology.

A Framework of Working Across Disciplines in Early Design and R&D of Large Complex Engineered Systems

NASA Technical Reports Server (NTRS)

McGowan, Anna-Maria Rivas; Papalambros, Panos Y.; Baker, Wayne E.

2015-01-01

This paper examines four primary methods of working across disciplines during R&D and early design of large-scale complex engineered systems such as aerospace systems. A conceptualized framework, called the Combining System Elements framework, is presented to delineate several aspects of cross-discipline and system integration practice. The framework is derived from a theoretical and empirical analysis of current work practices in actual operational settings and is informed by theories from organization science and engineering. The explanatory framework may be used by teams to clarify assumptions and associated work practices, which may reduce ambiguity in understanding diverse approaches to early systems research, development and design. The framework also highlights that very different engineering results may be obtained depending on work practices, even when the goals for the engineered system are the same.

Development of natural gas rotary engines

NASA Astrophysics Data System (ADS)

Mack, J. R.

1991-08-01

Development of natural gas-fueled rotary engines was pursued on the parallel paths of converted Mazda automotive engines and of establishing technology and demonstration of a test model of a larger John Deer Technologies Incorporated (JDTI) rotary engine with power capability of 250 HP per power section for future production of multi-rotor engines with power ratings 250, 500, and 1000 HP and upward. Mazda engines were converted to natural gas and were characterized by a laboratory which was followed by nearly 12,000 hours of testing in three different field installations. To develop technology for the larger JDTI engine, laboratory and engine materials testing was accomplished. Extensive combustion analysis computer codes were modified, verified, and utilized to predict engine performance, to guide parameters for actual engine design, and to identify further improvements. A single rotor test engine of 5.8 liter displacement was designed for natural gas operation based on the JDTI 580 engine series. This engine was built and tested. It ran well and essentially achieved predicted performance. Lean combustion and low NOW emission were demonstrated.

Tutorial on Actual Space Environmental Hazards For Space Systems (Invited)

NASA Astrophysics Data System (ADS)

Mazur, J. E.; Fennell, J. F.; Guild, T. B.; O'Brien, T. P.

2013-12-01

It has become common in the space science community to conduct research on diverse physical phenomena because they are thought to contribute to space weather. However, satellites contend with only three primary environmental hazards: single event effects, vehicle charging, and total dose, and not every physical phenomenon that occurs in space contributes in substantial ways to create these hazards. One consequence of the mismatch between actual threats and all-encompassing research is the often-described gap between research and operations; another is the creation of forecasts that provide no actionable information for design engineers or spacecraft operators. An example of the latter is the physics of magnetic field emergence on the Sun; the phenomenon is relevant to the formation and launch of coronal mass ejections and is also causally related to the solar energetic particles that may get accelerated in the interplanetary shock. Unfortunately for the research community, the engineering community mitigates the space weather threat (single-event effects from heavy ions above ~50 MeV/nucleon) with a worst-case specification of the environment and not with a prediction. Worst-case definition requires data mining of past events, while predictions involve large-scale systems science from the Sun to the Earth that is compelling for scientists and their funding agencies but not actionable for design or for most operations. Differing priorities among different space-faring organizations only compounds the confusion over what science research is relevant. Solar particle impacts to human crew arise mainly from the total ionizing dose from the solar protons, so the priority for prediction in the human spaceflight community is therefore much different than in the unmanned satellite community, while both communities refer to the fundamental phenomenon as space weather. Our goal in this paper is the presentation of a brief tutorial on the primary space environmental phenomena that are relevant to satellite design and operations. The tutorial will help space science researchers to understand the differing priorities of communities that operate in space and to better distinguish the science that is actually needed for the design and operation of all-weather space systems.

Real-Time Rocket/Vehicle System Integrated Health Management Laboratory For Development and Testing of Health Monitoring/Management Systems

NASA Technical Reports Server (NTRS)

Aguilar, R.

2006-01-01

Pratt & Whitney Rocketdyne has developed a real-time engine/vehicle system integrated health management laboratory, or testbed, for developing and testing health management system concepts. This laboratory simulates components of an integrated system such as the rocket engine, rocket engine controller, vehicle or test controller, as well as a health management computer on separate general purpose computers. These general purpose computers can be replaced with more realistic components such as actual electronic controllers and valve actuators for hardware-in-the-loop simulation. Various engine configurations and propellant combinations are available. Fault or failure insertion capability on-the-fly using direct memory insertion from a user console is used to test system detection and response. The laboratory is currently capable of simulating the flow-path of a single rocket engine but work is underway to include structural and multiengine simulation capability as well as a dedicated data acquisition system. The ultimate goal is to simulate as accurately and realistically as possible the environment in which the health management system will operate including noise, dynamic response of the engine/engine controller, sensor time delays, and asynchronous operation of the various components. The rationale for the laboratory is also discussed including limited alternatives for demonstrating the effectiveness and safety of a flight system.

A Rainbow View of NASA's RS-25 Engine Test

NASA Image and Video Library

2017-02-22

NASA engineers conducted their first RS-25 test of 2017 on the A-1 Test Stand at Stennis Space Center near Bay St. Louis, Mississippi, on Feb. 22, continuing to collect data on the performance of the rocket engine that will help power the new Space Launch System (SLS) rocket. Shown from the viewpoint of an overhead drone, the test of development engine No. 0528 ran the scheduled 380 seconds (six minutes and 20 seconds), allowing engineers to monitor various engine operating conditions. The test represents another step forward in development of the rocket that will launch humans aboard Orion deeper into space than ever before. Four RS-25 engines, together with a pair of solid rocket boosters, will power the SLS at launch on its deep-space missions. The engines for the first four SLS flights are former space shuttle main engines, which were tested extensively at Stennis and are some of the most proven engines in the world. Engineers are conducting an ongoing series of tests this year for SLS on both development and flight engines for future flights to ensure the engine, outfitted with a new controller, can perform at the higher level under a variety of conditions and situations. Stennis is also preparing its B-2 Test Stand to test the core stage for the first SLS flight with Orion, known as Exploration Mission-1. That testing will involve installing the flight stage on the stand and firing its four RS-25 engines simultaneously, just as during an actual launch. The Feb. 22 test was conducted by Aerojet Rocketdyne and Syncom Space Services engineers and operators. Aerojet Rocketdyne is the prime contractor for the RS-25 engines. Syncom Space Services is the prime contractor for Stennis facilities and operations. PAO Name:Kim Henry Phone Number:256-544-1899 Email Address: kimberly.m.henry@nasa.gov

Development and Validation of an NPSS Model of a Small Turbojet Engine

NASA Astrophysics Data System (ADS)

Vannoy, Stephen Michael

Recent studies have shown that integrated gas turbine engine (GT)/solid oxide fuel cell (SOFC) systems for combined propulsion and power on aircraft offer a promising method for more efficient onboard electrical power generation. However, it appears that nobody has actually attempted to construct a hybrid GT/SOFC prototype for combined propulsion and electrical power generation. This thesis contributes to this ambition by developing an experimentally validated thermodynamic model of a small gas turbine (˜230 N thrust) platform for a bench-scale GT/SOFC system. The thermodynamic model is implemented in a NASA-developed software environment called Numerical Propulsion System Simulation (NPSS). An indoor test facility was constructed to measure the engine's performance parameters: thrust, air flow rate, fuel flow rate, engine speed (RPM), and all axial stage stagnation temperatures and pressures. The NPSS model predictions are compared to the measured performance parameters for steady state engine operation.

Intelligent Control and Health Monitoring. Chapter 3

NASA Technical Reports Server (NTRS)

Garg, Sanjay; Kumar, Aditya; Mathews, H. Kirk; Rosenfeld, Taylor; Rybarik, Pavol; Viassolo, Daniel E.

2009-01-01

Advanced model-based control architecture overcomes the limitations state-of-the-art engine control and provides the potential of virtual sensors, for example for thrust and stall margin. "Tracking filters" are used to adapt the control parameters to actual conditions and to individual engines. For health monitoring standalone monitoring units will be used for on-board analysis to determine the general engine health and detect and isolate sudden faults. Adaptive models open up the possibility of adapting the control logic to maintain desired performance in the presence of engine degradation or to accommodate any faults. Improved and new sensors are required to allow sensing at stations within the engine gas path that are currently not instrumented due in part to the harsh conditions including high operating temperatures and to allow additional monitoring of vibration, mass flows and energy properties, exhaust gas composition, and gas path debris. The environmental and performance requirements for these sensors are summarized.

What scaling means in wind engineering: Complementary role of the reduced scale approach in a BLWT and the full scale testing in a large climatic wind tunnel

NASA Astrophysics Data System (ADS)

Flamand, Olivier

2017-12-01

Wind engineering problems are commonly studied by wind tunnel experiments at a reduced scale. This introduces several limitations and calls for a careful planning of the tests and the interpretation of the experimental results. The talk first revisits the similitude laws and discusses how they are actually applied in wind engineering. It will also remind readers why different scaling laws govern in different wind engineering problems. Secondly, the paper focuses on the ways to simplify a detailed structure (bridge, building, platform) when fabricating the downscaled models for the tests. This will be illustrated by several examples from recent engineering projects. Finally, under the most severe weather conditions, manmade structures and equipment should remain operational. What “recreating the climate” means and aims to achieve will be illustrated through common practice in climatic wind tunnel modelling.

Data engineering systems: Computerized modeling and data bank capabilities for engineering analysis

NASA Technical Reports Server (NTRS)

Kopp, H.; Trettau, R.; Zolotar, B.

1984-01-01

The Data Engineering System (DES) is a computer-based system that organizes technical data and provides automated mechanisms for storage, retrieval, and engineering analysis. The DES combines the benefits of a structured data base system with automated links to large-scale analysis codes. While the DES provides the user with many of the capabilities of a computer-aided design (CAD) system, the systems are actually quite different in several respects. A typical CAD system emphasizes interactive graphics capabilities and organizes data in a manner that optimizes these graphics. On the other hand, the DES is a computer-aided engineering system intended for the engineer who must operationally understand an existing or planned design or who desires to carry out additional technical analysis based on a particular design. The DES emphasizes data retrieval in a form that not only provides the engineer access to search and display the data but also links the data automatically with the computer analysis codes.

Systems engineering interfaces: A model based approach

NASA Astrophysics Data System (ADS)

Fosse, E.; Delp, C. L.

The engineering of interfaces is a critical function of the discipline of Systems Engineering. Included in interface engineering are instances of interaction. Interfaces provide the specifications of the relevant properties of a system or component that can be connected to other systems or components while instances of interaction are identified in order to specify the actual integration to other systems or components. Current Systems Engineering practices rely on a variety of documents and diagrams to describe interface specifications and instances of interaction. The SysML[1] specification provides a precise model based representation for interfaces and interface instance integration. This paper will describe interface engineering as implemented by the Operations Revitalization Task using SysML, starting with a generic case and culminating with a focus on a Flight System to Ground Interaction. The reusability of the interface engineering approach presented as well as its extensibility to more complex interfaces and interactions will be shown. Model-derived tables will support the case studies shown and are examples of model-based documentation products.

Computer Generated Diffraction Patterns Of Rough Surfaces

NASA Astrophysics Data System (ADS)

Rakels, Jan H.

1989-03-01

It is generally accepted, that optical methods are the most promising for the in-process measurement of surface finish. These methods have the advantages of being non-contacting and fast data acquisition. In the Micro-Engineering Centre at the University of Warwick, an optical sensor has been devised which can measure the rms roughness, slope and wavelength of turned and precision ground surfaces. The operation of this device is based upon the Kirchhoff-Fresnel diffraction integral. Application of this theory to ideal turned surfaces is straightforward, and indeed the theoretically calculated diffraction patterns are in close agreement with patterns produced by an actual optical instrument. Since it is mathematically difficult to introduce real surface profiles into the diffraction integral, a computer program has been devised, which simulates the operation of the optical sensor. The program produces a diffraction pattern as a graphical output. Comparison between computer generated and actual diffraction patterns of the same surfaces show a high correlation.

Experiment Comparison between Engineering Acid Dew Point and Thermodynamic Acid Dew Point

NASA Astrophysics Data System (ADS)

Song, Jinghui; Yuan, Hui; Deng, Jianhua

2018-06-01

in order to realize the accurate prediction of acid dew point, a set of measurement system of acid dew point for the flue gas flue gas in the tail of the boiler was designed and built, And measured at the outlet of an air preheater of a power plant of 1 000 MW, The results show that: Under the same conditions, with the test temperature decreases, Nu of heat transfer tubes, fouling and corrosion of pipe wall and corrosion pieces gradually deepened. Then, the measured acid dew point is compared with the acid dew point obtained by using the existing empirical formula under the same coal type. The dew point of engineering acid is usually about 40 ° lower than the dew point of thermodynamic acid because of the coupling effect of fouling on the acid liquid, which can better reflect the actual operation of flue gas in engineering and has certain theoretical guidance for the design and operation of deep waste heat utilization system significance.

Optimization in the systems engineering process

NASA Technical Reports Server (NTRS)

Lemmerman, Loren A.

1993-01-01

The essential elements of the design process consist of the mission definition phase that provides the system requirements, the conceptual design, the preliminary design and finally the detailed design. Mission definition is performed largely by operations analysts in conjunction with the customer. The result of their study is handed off to the systems engineers for documentation as the systems requirements. The document that provides these requirements is the basis for the further design work of the design engineers at the Lockheed-Georgia Company. The design phase actually begins with conceptual design, which is generally conducted by a small group of engineers using multidisciplinary design programs. Because of the complexity of the design problem, the analyses are relatively simple and generally dependent on parametric analyses of the configuration. The result of this phase is a baseline configuration from which preliminary design may be initiated.

Calculation of odour emissions from aircraft engines at Copenhagen Airport.

PubMed

Winther, Morten; Kousgaard, Uffe; Oxbøl, Arne

2006-07-31

In a new approach the odour emissions from aircraft engines at Copenhagen Airport are calculated using actual fuel flow and emission measurements (one main engine and one APU: Auxiliary Power Unit), odour panel results, engine specific data and aircraft operational data for seven busy days. The calculation principle assumes a linear relation between odour and HC emissions. Using a digitalisation of the aircraft movements in the airport area, the results are depicted on grid maps, clearly reflecting aircraft operational statistics as single flights or total activity during a whole day. The results clearly reflect the short-term temporal fluctuations of the emissions of odour (and exhaust gases). Aircraft operating at low engine thrust (taxiing, queuing and landing) have a total odour emission share of almost 98%, whereas the shares for the take off/climb out phases (2%) and APU usage (0.5%) are only marginal. In most hours of the day, the largest odour emissions occur, when the total amount of fuel burned during idle is high. However, significantly higher HC emissions for one specific engine cause considerable amounts of odour emissions during limited time periods. The experimentally derived odour emission factor of 57 OU/mg HC is within the range of 23 and 110 OU/mg HC used in other airport odour studies. The distribution of odour emission results between aircraft operational phases also correspond very well with the results for these other studies. The present study uses measurement data for a representative engine. However, the uncertainties become large when the experimental data is used to estimate the odour emissions for all aircraft engines. More experimental data is needed to increase inventory accuracy, and in terms of completeness it is recommended to make odour emission estimates also for engine start and the fuelling of aircraft at Copenhagen Airport in the future.

Jet Penetration into a Scaled Microfabricated Stirling Cycle Regenerator

NASA Technical Reports Server (NTRS)

Sun, Liyong; Simon, Terrence W.; Mantell, Susan; Ibrahim, Mournir; Gedeon, David; Tew, Roy

2008-01-01

The cooler and heater adjacent to the regenerator of a Stirling cycle engine have tubes or channels which form jets that pass into the regenerator while diffusing within the matrix. An inactive part of the matrix, beyond the cores of these jets, does not participate fully in the heat transfer between the flow of working fluid and the regenerator matrix material, weakening the regenerator s ability to exchange heat with the working fluid. The objective of the present program is to document this effect on the performance of the regenerator and to develop a model for generalizing the results. However, the small scales of actual Stirling regenerator matrices (on the order of tens of microns) make direct measurements of this effect very difficult. As a result, jet spreading within a regenerator matrix has not been characterized well and is poorly understood. Also, modeling is lacking experimental verification. To address this, a large-scale mockup of thirty times actual scale was constructed and operated under conditions that are dynamically similar to the engine operation. Jet penetration with round jets and slot jets into the microfabricated regenerator geometry are then measured by conventional means. The results are compared with those from a study of spreading of round jets within woven screen regenerator for further documentation of the comparative performance of the microfabricated regenerator geometry.

Constructing engineers through practice: Gendered features of learning and identity development

NASA Astrophysics Data System (ADS)

Tonso, Karen L.

How do women and men student engineers develop an engineering identity (a sense of belonging, or not), while practicing "actual" engineering? What are the influences of gender, learning and knowledge, relations of power, and conceptions of equality on cultural identity development? I studied these issues in reform-minded engineering design classes, courses organized around teaching students communications, teamwork, and practical engineering. Engineering-student cultural identity categories revealed a status hierarchy, predicated on meeting "academic" criteria for excellence, and the almost total exclusion of women. While working as an engineering colleague on five student teams (three first-year and two senior) and attending their design classes, I documented how cultural identities were made evident and constructed in students' practical engineering. Design projects promoted linking academic knowledge with real-world situations, sharing responsibilities and trusting colleagues, communicating engineering knowledge to technical and non-technical members of business communities, and addressing gaps in students' knowledge. With a curriculum analysis and survey of students' perceptions of the differences between design and conventional courses, I embedded the design classes in the wider campus and found that: (1) Engineering education conferred prestige, power, and well-paying jobs on students who performed "academic" engineering, while failing to adequately encourage "actual" engineering practices. High-status student engineers were the least likely to perform "actual" engineering in design teams. (2) Engineering education advanced an ideology that encouraged its practitioners to consider men's privilege and women's invisibility normal. By making "acting like men act" the standards to which engineering students must conform, women learned to put up with oppressive treatment. Women's accepting their own mistreatment and hiding their womanhood became a condition of women's belonging. (3) Despite all of the pressures to do otherwise, (some) teams of students (at all levels) carved out small oases where "actual" engineering prevailed and women's participation was robust. Students--not faculty, not progressive pedagogy, not "reformed" courses--disrupted prevailing norms. However, two women engineering students, one on each senior team, performed fabulous "actual" engineering, yet neither of them had a job when they graduated--the only two senior students on my teams without jobs.

Thermal modeling in an engine cooling system to control coolant flow for fuel consumption improvement

NASA Astrophysics Data System (ADS)

Park, Sangki; Woo, Seungchul; Kim, Minho; Lee, Kihyung

2017-04-01

The design and evaluation of engine cooling and lubrication systems is generally based on real vehicle tests. Our goal here was to establish an engine heat balance model based on mathematical and interpretive analysis of each element of a passenger diesel engine cooling system using a 1-D numerical model. The purpose of this model is to determine ways of optimizing the cooling and lubrication components of an engine and then to apply these methods to actual cooling and lubrication systems of engines that will be developed in the future. Our model was operated under the New European Driving Cycle (NEDC) mode conditions, which represent the fuel economy evaluation mode in Europe. The flow rate of the cooling system was controlled using a control valve. Our results showed that the fuel efficiency was improved by as much as 1.23 %, cooling loss by 1.35 %, and friction loss by 2.21 % throughout NEDC modes by modification of control conditions.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neitzel, D.A.; McKenzie, D.H.

To minimize adverse impact on aquatic ecosystems resulting from the operation of water intake structures, design engineers must have relevant information on the behavior, physiology and ecology of local fish and shellfish. Identification of stimulus/response relationships and the environmental factors that influence them is the first step in incorporating biological information in the design, location or modification of water intake structures. A procedure is presented in this document for providing biological input to engineers who are designing, locating or modifying a water intake structure. The authors discuss sources of stimuli at water intakes, historical approaches in assessing potential/actual impact andmore » review biological information needed for intake design.« less

Laboratory experiments in integrated circuit fabrication

NASA Technical Reports Server (NTRS)

Jenkins, Thomas J.; Kolesar, Edward S.

1993-01-01

The objectives of the experiment are fourfold: to provide practical experience implementing the fundamental processes and technology associated with the science and art of integrated circuit (IC) fabrication; to afford the opportunity for the student to apply the theory associated with IC fabrication and semiconductor device operation; to motivate the student to exercise engineering decisions associated with fabricating integrated circuits; and to complement the theory of n-channel MOS and diffused devices that are presented in the classroom by actually fabricating and testing them. Therefore, a balance between theory and practice can be realized in the education of young engineers, whose education is often criticized as lacking sufficient design and practical content.

In-Flight Thermal Performance of the Lidar In-Space Technology Experiment

NASA Technical Reports Server (NTRS)

Roettker, William

1995-01-01

The Lidar In-Space Technology Experiment (LITE) was developed at NASA s Langley Research Center to explore the applications of lidar operated from an orbital platform. As a technology demonstration experiment, LITE was developed to gain experience designing and building future operational orbiting lidar systems. Since LITE was the first lidar system to be flown in space, an important objective was to validate instrument design principles in such areas as thermal control, laser performance, instrument alignment and control, and autonomous operations. Thermal and structural analysis models of the instrument were developed during the design process to predict the behavior of the instrument during its mission. In order to validate those mathematical models, extensive engineering data was recorded during all phases of LITE's mission. This inflight engineering data was compared with preflight predictions and, when required, adjustments to the thermal and structural models were made to more accurately match the instrument s actual behavior. The results of this process for the thermal analysis and design of LITE are presented in this paper.

Development and evaluation of a general aviation real world noise simulator

NASA Technical Reports Server (NTRS)

Galanter, E.; Popper, R.

1980-01-01

An acoustic playback system is described which realistically simulates the sounds experienced by the pilot of a general aviation aircraft during engine idle, take-off, climb, cruise, descent, and landing. The physical parameters of the signal as they appear in the simulator environment are compared to analogous parameters derived from signals recorded during actual flight operations. The acoustic parameters of the simulated and real signals during cruise conditions are within plus or minus two dB in third octave bands from 0.04 to 4 kHz. The overall A-weighted levels of the signals are within one dB of signals generated in the actual aircraft during equivalent maneuvers. Psychoacoustic evaluations of the simulator signal are compared with similar measurements based on transcriptions of actual aircraft signals. The subjective judgments made by human observers support the conclusion that the simulated sound closely approximates transcribed sounds of real aircraft.

Optical Diagnosis of Gas Turbine Combustors Being Conducted

NASA Technical Reports Server (NTRS)

Hicks, Yolanda R.; Locke, Randy J.; Anderson, Robert C.; DeGroot, Wilhelmus A.

2001-01-01

Researchers at the NASA Glenn Research Center, in collaboration with industry, are reducing gas turbine engine emissions by studying visually the air-fuel interactions and combustion processes in combustors. This is especially critical for next generation engines that, in order to be more fuel-efficient, operate at higher temperatures and pressures than the current fleet engines. Optically based experiments were conducted in support of the Ultra-Efficient Engine Technology program in Glenn's unique, world-class, advanced subsonic combustion rig (ASCR) facility. The ASCR can supply air and jet fuel at the flow rates, temperatures, and pressures that simulate the conditions expected in the combustors of high-performance, civilian aircraft engines. In addition, this facility is large enough to support true sectors ("pie" slices of a full annular combustor). Sectors enable one to test true shapes rather than rectangular approximations of the actual hardware. Therefore, there is no compromise to actual engine geometry. A schematic drawing of the sector test stand is shown. The test hardware is mounted just upstream of the instrumentation section. The test stand can accommodate hardware up to 0.76-m diameter by 1.2-m long; thus sectors or small full annular combustors can be examined in this facility. Planar (two-dimensional) imaging using laser-induced fluorescence and Mie scattering, chemiluminescence, and video imagery were obtained for a variety of engine cycle conditions. The hardware tested was a double annular sector (two adjacent fuel injectors aligned radially) representing approximately 15 of a full annular combustor. An example of the two-dimensional data obtained for this configuration is also shown. The fluorescence data show the location of fuel and hydroxyl radical (OH) along the centerline of the fuel injectors. The chemiluminescence data show C2 within the total observable volume. The top row of this figure shows images obtained at an engine low-power condition, and the bottom row shows data from a higher power operating point. The data show distinctly the differences in flame structure between low-power and high-power engine conditions, in both location and amount of species produced (OH, C2) or consumed (fuel). The unique capability of the facility coupled with its optical accessibility helps to eliminate the need for high-pressure performance extrapolations. Tests such as described here have been used successfully to assess the performance of fuel-injection concepts and to modify those designs, if needed.

Analytical condition inspection and extension of time between overhaul of F3-30 engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nakao, M.; Ikeyama, M.; Abe, S.

1992-04-01

F3-30 is the low-bypass-ratio turbofan engine developed to power the T-4 intermediate trainer for the Japan Air Self Defense Force (JASDF). The actual field service was started in Sept., 1988. This paper reports on the program to extend time between overhaul (TBO) of the F3-30 which has been running. Analytical condition inspection (ACI) and accelerated mission testing (AMT) were conducted to confirm sufficient durability to extend TBO. Most deteriorations of parts and performance due to AMT were also found by ACI after field operation with approximately the same deterioration rate. On the other hand, some deteriorations were found by ACImore » only. These results show that ACI after field operation is also necessary to confirm the TBO extension, although AMT simulates the deterioration in field operations very well. The deteriorations that would be caused by the field operation during one extended-TBO were estimated with the results of ACI and AMT, and it was concluded that the F3-30 has sufficient durability for TBO extension to the next step.« less

Conductometric Sensor for Soot Mass Flow Detection in Exhausts of Internal Combustion Engines

PubMed Central

Feulner, Markus; Hagen, Gunter; Müller, Andreas; Schott, Andreas; Zöllner, Christian; Brüggemann, Dieter; Moos, Ralf

2015-01-01

Soot sensors are required for on-board diagnostics (OBD) of automotive diesel particulate filters (DPF) to detect filter failures. Widely used for this purpose are conductometric sensors, measuring an electrical current or resistance between two electrodes. Soot particles deposit on the electrodes, which leads to an increase in current or decrease in resistance. If installed upstream of a DPF, the “engine-out” soot emissions can also be determined directly by soot sensors. Sensors were characterized in diesel engine real exhausts under varying operation conditions and with two different kinds of diesel fuel. The sensor signal was correlated to the actual soot mass and particle number, measured with an SMPS. Sensor data and soot analytics (SMPS) agreed very well, an impressing linear correlation in a double logarithmic representation was found. This behavior was even independent of the used engine settings or of the biodiesel content. PMID:26580621

Conductometric Sensor for Soot Mass Flow Detection in Exhausts of Internal Combustion Engines.

PubMed

Feulner, Markus; Hagen, Gunter; Müller, Andreas; Schott, Andreas; Zöllner, Christian; Brüggemann, Dieter; Moos, Ralf

2015-11-13

Soot sensors are required for on-board diagnostics (OBD) of automotive diesel particulate filters (DPF) to detect filter failures. Widely used for this purpose are conductometric sensors, measuring an electrical current or resistance between two electrodes. Soot particles deposit on the electrodes, which leads to an increase in current or decrease in resistance. If installed upstream of a DPF, the "engine-out" soot emissions can also be determined directly by soot sensors. Sensors were characterized in diesel engine real exhausts under varying operation conditions and with two different kinds of diesel fuel. The sensor signal was correlated to the actual soot mass and particle number, measured with an SMPS. Sensor data and soot analytics (SMPS) agreed very well, an impressing linear correlation in a double logarithmic representation was found. This behavior was even independent of the used engine settings or of the biodiesel content.

Investigation on cause of the elevator turbine wear

NASA Astrophysics Data System (ADS)

Zhang, J.; Ouyang, W. P.; Xue, J. A.

2018-03-01

Elevator traction turbine is often worn for various reasons, causing serious safety hazard. It is explained the main causes of traction wheel wear in detail in combination with a large number of engineering experience. The effect of turbine wear on the actual operation of the elevator is verified by contrast experiment, which is helpful to identify risks early. It is put forward on some reasonable suggestions for elevator inspection, maintenance and management.

Carbon monoxide poisonings from small, gasoline-powered, internal combustion engines: just what is a "well-ventilated area"?

PubMed

Earnest, G S; Mickelsen, R L; McCammon, J B; O'Brien, D M

1997-11-01

This study modeled the time required for a gasoline-powered, 5 horsepower (hp), 4-cycle engine to generate carbon monoxide (CO) concentrations exceeding the National Institute for Occupational Safety and Health 200-ppm ceiling and 1200-ppm immediately dangerous to life and health concentration for various room sizes and ventilation rates. The model permitted the ambiguous term "well-ventilated area" to be defined. The model was compared with field data collected at a site where two workers were poisoned while operating a 5-hp concrete saw in a bathroom having open doors and an operating ventilation system. There is agreement between both the modeled and field-generated data, indicating that hazardous CO concentrations can develop within minutes. Comparison of field and modeling data showed the measured CO generation rate at approximately one-half of the value used in the model, which may be partially because the engine used in the field was not under load during data collection. The generation rate and room size from the actual poisoning was then used in the model. The model determined that ventilation rates of nearly 5000 ft3/min (120 air changes per hour) would be required to prevent the CO concentration from exceeding the 200-ppm ceiling for short periods. Results suggest that small gasoline-powered engines should not be operated inside of buildings or in semienclosed spaces and that manufacturers of such tools should improve their warnings and develop engineering control options for better user protection.

Orbital transfer vehicle oxygen turbopump technology. Volume 3: Hot oxygen testing

NASA Technical Reports Server (NTRS)

Urke, Robert L.

1992-01-01

This report covers the work done in preparation for a liquid oxygen rocket engine turbopump test utilizing high pressure hot oxygen gas for the turbine drive. The turbopump (TPA) is designed to operate with 400 F oxygen turbine drive gas. The goal of this test program was to demonstrate the successful operation of the TPA under simulated engine conditions including the hot oxygen turbine drive. This testing follows a highly successful series of tests pumping liquid oxygen with gaseous nitrogen as the turbine drive gas. That testing included starting of the TPA with no assist to the hydrostatic bearing. The bearing start entailed a rubbing start until the pump generated enough pressure to support the bearing. The articulating, self-centering hydrostatic bearing exhibited no bearing load or stability problems. The TPA was refurbished for the hot gas drive tests and facility work was begun, but unfortunately funding cuts prohibited the actual testing.

PSC algorithm description

NASA Technical Reports Server (NTRS)

Nobbs, Steven G.

1995-01-01

An overview of the performance seeking control (PSC) algorithm and details of the important components of the algorithm are given. The onboard propulsion system models, the linear programming optimization, and engine control interface are described. The PSC algorithm receives input from various computers on the aircraft including the digital flight computer, digital engine control, and electronic inlet control. The PSC algorithm contains compact models of the propulsion system including the inlet, engine, and nozzle. The models compute propulsion system parameters, such as inlet drag and fan stall margin, which are not directly measurable in flight. The compact models also compute sensitivities of the propulsion system parameters to change in control variables. The engine model consists of a linear steady state variable model (SSVM) and a nonlinear model. The SSVM is updated with efficiency factors calculated in the engine model update logic, or Kalman filter. The efficiency factors are used to adjust the SSVM to match the actual engine. The propulsion system models are mathematically integrated to form an overall propulsion system model. The propulsion system model is then optimized using a linear programming optimization scheme. The goal of the optimization is determined from the selected PSC mode of operation. The resulting trims are used to compute a new operating point about which the optimization process is repeated. This process is continued until an overall (global) optimum is reached before applying the trims to the controllers.

Slot angle detecting method for fiber fixed chip

NASA Astrophysics Data System (ADS)

Zhang, Jiaquan; Wang, Jiliang; Zhou, Chaochao

2018-04-01

The slot angle of fiber fixed chip has a significant impact on performance of photoelectric devices. In order to solve the actual engineering problem, this paper put forward a detecting method based on imaging processing. Because the images have very low contrast that is hardly segmented, so this paper proposes imaging segment methods based on edge character. Then get fixed chip edge line slope k2 and calculate the fiber fixed slot line slope k1, which can be used calculating the slot angle. Lastly, test the repeatability and accuracy of system, which show that this method has very fast operation speed and good robustness. Clearly, it is also satisfied to the actual demand of fiber fixed chip slot angle detection.

Advanced Gas Turbine (AGT) technology report

NASA Technical Reports Server (NTRS)

1985-01-01

Engine testing, ceramic component fabrication and evaluation, component performance rig testing, and producibility experiments at Pontiac comprised AGT 100 activities of this period, January to December 1984. Two experimental engines were available and allowed the evaluation of eight experimental assemblies. Operating time accumulated was 115 hr of burning and 156 hr total. Total cumulative engine operating time is now 225 hr. Build number 11 and 12 of engine S/N 1 totaled 28 burning hours and constituted a single assembly of the engine core--the compressor, both turbines, and the gearbox. Build number 11 of engine S/N 1 included a 1:07 hr continuous test at 100% gasifier speed (86,000 rpm). Build number 8 of engine S/N 2 was the first engine test with a ceramic turbine rotor. A mechanical loss test of an engine assembly revealed the actual losses to be near the original design allowance. Component development activity included rig testing of the compressor, combustor, and regenerator. Compressor testing was initiated on a rig modified to control the transfer of heat between flow path, lubricating oil, and structure. Results show successful thermal decoupling of the rig and lubricating/cooling oil. Rig evaluation of a reduced-friction compressor was initiated. Combustor testing covered qualification of ceramic parts for engine use, mapping of operating range limits, and evaluation of a relocated igniter plug. Several seal refinements were tested on the hot regenerator rig. An alternate regenerator disk, extruded MAS, was examined and found to be currently inadequate for the AGT 100 application. Also, a new technique for measuring leakage was explored on the regenerator rig. Ceramic component activity has focused on the development of state-of-the-art material strength characteristics in full-scale hardware. Injection-molded sintered alpha-SiC rotors were produced at Carborundum in an extensive process and tool optimization study.

Emissions factors for gaseous and particulate pollutants from offshore diesel engine vessels in China

NASA Astrophysics Data System (ADS)

Zhang, F.; Chen, Y.; Tian, C.; Li, J.; Zhang, G.; Matthias, V.

2015-09-01

Shipping emissions have significant influence on atmospheric environment as well as human health, especially in coastal areas and the harbor districts. However, the contribution of shipping emissions on the environment in China still need to be clarified especially based on measurement data, with the large number ownership of vessels and the rapid developments of ports, international trade and shipbuilding industry. Pollutants in the gaseous phase (carbon monoxide, sulfur dioxide, nitrogen oxides, total volatile organic compounds) and particle phase (particulate matter, organic carbon, elemental carbon, sulfates, nitrate, ammonia, metals) in the exhaust from three different diesel engine power offshore vessels in China were measured in this study. Concentrations, fuel-based and power-based emissions factors for various operating modes as well as the impact of engine speed on emissions were determined. Observed concentrations and emissions factors for carbon monoxide, nitrogen oxides, total volatile organic compounds, and particulate matter were higher for the low engine power vessel than for the two higher engine power vessels. Fuel-based average emissions factors for all pollutants except sulfur dioxide in the low engine power engineering vessel were significantly higher than that of the previous studies, while for the two higher engine power vessels, the fuel-based average emissions factors for all pollutants were comparable to the results of the previous studies. The fuel-based average emissions factor for nitrogen oxides for the small engine power vessel was more than twice the International Maritime Organization standard, while those for the other two vessels were below the standard. Emissions factors for all three vessels were significantly different during different operating modes. Organic carbon and elemental carbon were the main components of particulate matter, while water-soluble ions and elements were present in trace amounts. Best-fit engine speeds during actual operation should be based on both emissions factors and economic costs.

Distinctions between intelligent manufactured and constructed systems and a new discipline for intelligent infrastructure hypersystems

NASA Astrophysics Data System (ADS)

Aktan, A. Emin

2003-08-01

Although the interconnected systems nature of the infrastructures, and the complexity of interactions between their engineered, socio-technical and natural constituents have been recognized for some time, the principles of effectively operating, protecting and preserving such systems by taking full advantage of "modeling, simulations, optimization, control and decision making" tools developed by the systems engineering and operations research community have not been adequately studied or discussed by many engineers including the writer. Differential and linear equation systems, numerical and finite element modeling techniques, statistical and probabilistic representations are universal, however, different disciplines have developed their distinct approaches to conceptualizing, idealizing and modeling the systems they commonly deal with. The challenge is in adapting and integrating deterministic and stochastic, geometric and numerical, physics-based and "soft (data-or-knowledge based)", macroscopic or microscopic models developed by various disciplines for simulating infrastructure systems. There is a lot to be learned by studying how different disciplines have studied, improved and optimized the systems relating to various processes and products in their domains. Operations research has become a fifty-year old discipline addressing complex systems problems. Its mathematical tools range from linear programming to decision processes and game theory. These tools are used extensively in management and finance, as well as by industrial engineers for optimizing and quality control. Progressive civil engineering academic programs have adopted "systems engineering" as a focal area. However, most of the civil engineering systems programs remain focused on constructing and analyzing highly idealized, often generic models relating to the planning or operation of transportation, water or waste systems, maintenance management, waste management or general infrastructure hazards risk management. We further note that in the last decade there have been efforts for "agent-based" modeling of synthetic infrastructure systems by taking advantage of supercomputers at various DOE Laboratories. However, whether there is any similitude between such synthetic and actual systems needs investigating further.

Reliability analysis of C-130 turboprop engine components using artificial neural network

NASA Astrophysics Data System (ADS)

Qattan, Nizar A.

In this study, we predict the failure rate of Lockheed C-130 Engine Turbine. More than thirty years of local operational field data were used for failure rate prediction and validation. The Weibull regression model and the Artificial Neural Network model including (feed-forward back-propagation, radial basis neural network, and multilayer perceptron neural network model); will be utilized to perform this study. For this purpose, the thesis will be divided into five major parts. First part deals with Weibull regression model to predict the turbine general failure rate, and the rate of failures that require overhaul maintenance. The second part will cover the Artificial Neural Network (ANN) model utilizing the feed-forward back-propagation algorithm as a learning rule. The MATLAB package will be used in order to build and design a code to simulate the given data, the inputs to the neural network are the independent variables, the output is the general failure rate of the turbine, and the failures which required overhaul maintenance. In the third part we predict the general failure rate of the turbine and the failures which require overhaul maintenance, using radial basis neural network model on MATLAB tool box. In the fourth part we compare the predictions of the feed-forward back-propagation model, with that of Weibull regression model, and radial basis neural network model. The results show that the failure rate predicted by the feed-forward back-propagation artificial neural network model is closer in agreement with radial basis neural network model compared with the actual field-data, than the failure rate predicted by the Weibull model. By the end of the study, we forecast the general failure rate of the Lockheed C-130 Engine Turbine, the failures which required overhaul maintenance and six categorical failures using multilayer perceptron neural network (MLP) model on DTREG commercial software. The results also give an insight into the reliability of the engine turbine under actual operating conditions, which can be used by aircraft operators for assessing system and component failures and customizing the maintenance programs recommended by the manufacturer.

Experimental quiet engine program aerodynamic performance of fan A

NASA Technical Reports Server (NTRS)

Giffin, R. G.; Parker, D. E.; Dunbar, L. W.

1971-01-01

The aerodynamic component test results are presented of fan A, one of two high-bypass-ratio, 1160 feet per second single-stage fans, which was designed and tested as part of the NASA Experimental Quiet Engine Program. This fan was designed to deliver a bypass pressure ratio of 1.50 with an adiabatic efficiency of 86.5% at a total fan flow of 950 lb/sec. It was tested with and without inlet flow distortion. A bypass total-pressure ratio of 1.52 and an adiabatic efficiency of 88.3% at a total fan flow of 962 lb/sec were actually achieved. An operating margin of 12.4% was demonstrated at design speed.

14 CFR 91.611 - Authorization for ferry flight with one engine inoperative.

Code of Federal Regulations, 2010 CFR

2010-01-01

... chapter but with— (i) The actual steady gradient of the final takeoff climb requirement not less than 1.2... less than the two-engine inoperative trim speed for the actual steady gradient of the final takeoff...

Exhaust emission control and diagnostics

DOEpatents

Mazur, Christopher John; Upadhyay, Devesh

2006-11-14

A diesel engine emission control system uses an upstream oxidation catalyst and a downstream SCR catalyst to reduce NOx in a lean exhaust gas environment. The engine and upstream oxidation catalyst are configured to provide approximately a 1:1 ratio of NO to NO2 entering the downstream catalyst. In this way, the downstream catalyst is insensitive to sulfur contamination, and also has improved overall catalyst NOx conversion efficiency. Degradation of the system is determined when the ratio provided is no longer near the desired 1:1 ratio. This condition is detected using measurements of engine operating conditions such as from a NOx sensor located downstream of the catalysts. Finally, control action to adjust an injected amount of reductant in the exhaust gas based on the actual NO to NO2 ratio upstream of the SCR catalyst and downstream of the oxidation catalyst.

Experimental Study of Ignition by Hot Spot in Internal Combustion Engines

NASA Technical Reports Server (NTRS)

Serruys, Max

1938-01-01

In order to carry out the contemplated study, it was first necessary to provide hot spots in the combustion chamber, which could be measured and whose temperature could be changed. It seemed difficult to realize both conditions working solely on the temperature of the cooling water in a way so as to produce hot spots on the cylinder wall capable of provoking autoignition. Moreover, in the majority of practical cases, autoignition is produced by the spark plug, one of the least cooled parts in the engine. The first procedure therefore did not resemble that which most generally occurs in actual engine operation. All of these considerations caused us to reproduce similar hot spots at the spark plugs. The hot spots produced were of two kinds and designated with the name of thermo-electric spark plug and of metallic hot spot.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahrens, J.S.

For over fifteen years Sandia National Laboratories has been involved in laboratory testing of biometric identification devices. The key concept of biometric identification devices is the ability for the system to identify some unique aspect of the individual rather than some object a person may be carrying or some password they are required to know. Tests were conducted to verify manufacturer`s performance claims, to determine strengths/weaknesses of devices, and to determine devices that meet the US Department of energy`s needs. However, during recent field installation, significantly different performance was observed than was predicted by laboratory tests. Although most people usingmore » the device believed it operated adequately, the performance observed was over an order of magnitude worse than predicted. The search for reasons behind this gap between the predicted and the actual performance has revealed many possible contributing factors. As engineers, the most valuable lesson to be learned from this experience is the value of scientists and engineers with (1) common sense, (2) knowledge of human behavior, (3) the ability to observe the real world, and (4) the capability to realize the significant differences between controlled experiments and actual installations.« less

Underground coal mine instrumentation and test

NASA Technical Reports Server (NTRS)

Burchill, R. F.; Waldron, W. D.

1976-01-01

The need to evaluate mechanical performance of mine tools and to obtain test performance data from candidate systems dictate that an engineering data recording system be built. Because of the wide range of test parameters which would be evaluated, a general purpose data gathering system was designed and assembled to permit maximum versatility. A primary objective of this program was to provide a specific operating evaluation of a longwall mining machine vibration response under normal operating conditions. A number of mines were visited and a candidate for test evaluation was selected, based upon management cooperation, machine suitability, and mine conditions. Actual mine testing took place in a West Virginia mine.

Facility Management as Part of an Integrated Design of Civil Engineering Structures

NASA Astrophysics Data System (ADS)

Hyben, Ivan; Podmanický, Peter

2014-11-01

The present article deals about facility management, as still relatively young component of an integrated planning and design of buildings. Attention is focused on the area of the proposal, which can greatly affect to amount of future operating costs. Operational efficiency has been divided into individual components and satisfaction with the solution of buildings already constructed was assessed by workers, who are actually dedicated facility management in these organizations. The results were then assessed and evaluated through regression analysis. The aim of this paper is to determine to what extent is desired update project documentation of new buildings from the perspective of facility management.

Tory II-A: a nuclear ramjet test reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hadley, J.W.

Declassified 28 Nov 1973. The first test reactor in the Pluto program, leading to development of a nuclear ramjet engine, is called Tory II-A. While it is not an actual prototype engine, this reactor embodies a core design which is considered feasible for an engine, and operation of the reactor will provide a test of that core type as well as more generalized values in reactor design and testing. The design of Tory II-A and construction of the reactor and of its test facility are described. Operation of the Tory II-A core at a total power of 160 megawatts, withmore » 800 pounds of air per second passing through the core and emerging at a temperature of 2000 deg F, is the central objective of the test program. All other reactor and facility components exist to support operation of the core, and preliminary steps in the test program itself will be directed primarily toward ensuring attalnment of full-power operation and collection of meaningful data on core behavior during that operation. The core, 3 feet in diameter and 41/2 feet long, will be composed of bundled ceramic tubes whose central holes will provide continuous air passages from end to end of the reactor. These tubes are to be composed of a homogeneous mixture of UO/sub 2/ fuel and BeO moderator, compacted and sintered to achieve high strength and density. (30 references) (auth)« less

2010 NASA Exploration Systems Mission Directorate: Lunabotics Mining Competition Systems Engineering Paper

NASA Technical Reports Server (NTRS)

2010-01-01

A fast growing approach in determining the best design concept for a problem is to hold a competition in which the rules are based on requirements similar to the actual problem. By going public with such competitions, sponsoring entities receive some of the most innovative engineering solutions in a fraction of the time and cost it would have taken to develop such concepts internally. Space exploration is a large benefactor of such design competitions as seen by the results of X-Prize Foundation and NASA lunar excavation competitions [1]. The results of NASA's past lunar excavator challenges has led to the need for an effective means of collecting lunar regolith in the absence of human beings. The 2010 Exploration Systems Mission Directorate (ESMD) Lunar Excavation Challenge was created "to engage and retain students in science, technology, engineering, and mathematics, or STEM, in a competitive environment that may result in innovative ideas and solutions, which could be applied to actual lunar excavation for NASA." [2]. The ESMD Challenge calls for "teams to use telerobotics or autonomous operations to excavate at least 10kg of lunar regolith simulant in a 15 minute time limit" [2]. The Systems Engineering approach was used in accordance with Auburn University's mechanical engineering senior design course (MECH 4240-50) to develop a telerobotic lunar excavator, seen in Fig. 1, that fulfilled requirements imposed by the NASA ESMD Competition Rules. The goal of the senior design project was to have a validated lunar excavator that would be used in the NASA ESMD lunar excavation challenge.

Metallurgical Plant Optimization Through the use of Flowsheet Simulation Modelling

NASA Astrophysics Data System (ADS)

Kennedy, Mark William

Modern metallurgical plants typically have complex flowsheets and operate on a continuous basis. Real time interactions within such processes can be complex and the impacts of streams such as recycles on process efficiency and stability can be highly unexpected prior to actual operation. Current desktop computing power, combined with state-of-the-art flowsheet simulation software like Metsim, allow for thorough analysis of designs to explore the interaction between operating rate, heat and mass balances and in particular the potential negative impact of recycles. Using plant information systems, it is possible to combine real plant data with simple steady state models, using dynamic data exchange links to allow for near real time de-bottlenecking of operations. Accurate analytical results can also be combined with detailed unit operations models to allow for feed-forward model-based-control. This paper will explore some examples of the application of Metsim to real world engineering and plant operational issues.

The Study the Vibration Condition of the Blade of the Gas Turbine Engine with an All-metal Wire Rope Damper in the Area Mount of the Blade to the Disk

NASA Astrophysics Data System (ADS)

Melentjev, Vladimir S.; Gvozdev, Alexander S.

2018-01-01

Improving the reliability of modern turbine engines is actual task. This is achieved due to prevent a vibration damage of the operating blades. On the department of structure and design of aircraft engines have accumulated a lot of experimental data on the protection of the blades of the gas turbine engine from a vibration. In this paper we proposed a method for calculating the characteristics of wire rope dampers in the root attachment of blade of a gas turbine engine. The method is based on the use of the finite element method and transient analysis. Contact interaction (Lagrange-Euler method) between the compressor blade and the disc of the rotor has been taken into account. Contribution of contact interaction between details in damping of the system was measured. The proposed method provides a convenient way for the iterative selection of the required parameters the wire rope elastic-damping element. This element is able to provide the necessary protection from the vibration for the blade of a gas turbine engine.

A Model-Based Anomaly Detection Approach for Analyzing Streaming Aircraft Engine Measurement Data

NASA Technical Reports Server (NTRS)

Simon, Donald L.; Rinehart, Aidan W.

2014-01-01

This paper presents a model-based anomaly detection architecture designed for analyzing streaming transient aircraft engine measurement data. The technique calculates and monitors residuals between sensed engine outputs and model predicted outputs for anomaly detection purposes. Pivotal to the performance of this technique is the ability to construct a model that accurately reflects the nominal operating performance of the engine. The dynamic model applied in the architecture is a piecewise linear design comprising steady-state trim points and dynamic state space matrices. A simple curve-fitting technique for updating the model trim point information based on steadystate information extracted from available nominal engine measurement data is presented. Results from the application of the model-based approach for processing actual engine test data are shown. These include both nominal fault-free test case data and seeded fault test case data. The results indicate that the updates applied to improve the model trim point information also improve anomaly detection performance. Recommendations for follow-on enhancements to the technique are also presented and discussed.

A Model-Based Anomaly Detection Approach for Analyzing Streaming Aircraft Engine Measurement Data

NASA Technical Reports Server (NTRS)

Simon, Donald L.; Rinehart, Aidan Walker

2015-01-01

This paper presents a model-based anomaly detection architecture designed for analyzing streaming transient aircraft engine measurement data. The technique calculates and monitors residuals between sensed engine outputs and model predicted outputs for anomaly detection purposes. Pivotal to the performance of this technique is the ability to construct a model that accurately reflects the nominal operating performance of the engine. The dynamic model applied in the architecture is a piecewise linear design comprising steady-state trim points and dynamic state space matrices. A simple curve-fitting technique for updating the model trim point information based on steadystate information extracted from available nominal engine measurement data is presented. Results from the application of the model-based approach for processing actual engine test data are shown. These include both nominal fault-free test case data and seeded fault test case data. The results indicate that the updates applied to improve the model trim point information also improve anomaly detection performance. Recommendations for follow-on enhancements to the technique are also presented and discussed.

Definition, technology readiness, and development cost of the orbit transfer vehicle engine integrated control and health monitoring system elements

NASA Technical Reports Server (NTRS)

Cannon, I.; Balcer, S.; Cochran, M.; Klop, J.; Peterson, S.

1991-01-01

An Integrated Control and Health Monitoring (ICHM) system was conceived for use on a 20 Klb thrust baseline Orbit Transfer Vehicle (OTV) engine. Considered for space used, the ICHM was defined for reusability requirements for an OTV engine service free life of 20 missions, with 100 starts and a total engine operational time of 4 hours. Functions were derived by flowing down requirements from NASA guidelines, previous OTV engine or ICHM documents, and related contracts. The elements of an ICHM were identified and listed, and these elements were described in sufficient detail to allow estimation of their technology readiness levels. These elements were assessed in terms of technology readiness level, and supporting rationale for these assessments presented. The remaining cost for development of a minimal ICHM system to technology readiness level 6 was estimated. The estimates are within an accuracy range of minus/plus 20 percent. The cost estimates cover what is needed to prepare an ICHM system for use on a focussed testbed for an expander cycle engine, excluding support to the actual test firings.

Mass Analyzers Facilitate Research on Addiction

NASA Technical Reports Server (NTRS)

2012-01-01

The famous go/no go command for Space Shuttle launches comes from a place called the Firing Room. Located at Kennedy Space Center in the Launch Control Center (LCC), there are actually four Firing Rooms that take up most of the third floor of the LCC. These rooms comprise the nerve center for Space Shuttle launch and processing. Test engineers in the Firing Rooms operate the Launch Processing System (LPS), which is a highly automated, computer-controlled system for assembly, checkout, and launch of the Space Shuttle. LPS monitors thousands of measurements on the Space Shuttle and its ground support equipment, compares them to predefined tolerance levels, and then displays values that are out of tolerance. Firing Room operators view the data and send commands about everything from propellant levels inside the external tank to temperatures inside the crew compartment. In many cases, LPS will automatically react to abnormal conditions and perform related functions without test engineer intervention; however, firing room engineers continue to look at each and every happening to ensure a safe launch. Some of the systems monitored during launch operations include electrical, cooling, communications, and computers. One of the thousands of measurements derived from these systems is the amount of hydrogen and oxygen inside the shuttle during launch.

Adaptive Optimization of Aircraft Engine Performance Using Neural Networks

NASA Technical Reports Server (NTRS)

Simon, Donald L.; Long, Theresa W.

1995-01-01

Preliminary results are presented on the development of an adaptive neural network based control algorithm to enhance aircraft engine performance. This work builds upon a previous National Aeronautics and Space Administration (NASA) effort known as Performance Seeking Control (PSC). PSC is an adaptive control algorithm which contains a model of the aircraft's propulsion system which is updated on-line to match the operation of the aircraft's actual propulsion system. Information from the on-line model is used to adapt the control system during flight to allow optimal operation of the aircraft's propulsion system (inlet, engine, and nozzle) to improve aircraft engine performance without compromising reliability or operability. Performance Seeking Control has been shown to yield reductions in fuel flow, increases in thrust, and reductions in engine fan turbine inlet temperature. The neural network based adaptive control, like PSC, will contain a model of the propulsion system which will be used to calculate optimal control commands on-line. Hopes are that it will be able to provide some additional benefits above and beyond those of PSC. The PSC algorithm is computationally intensive, it is valid only at near steady-state flight conditions, and it has no way to adapt or learn on-line. These issues are being addressed in the development of the optimal neural controller. Specialized neural network processing hardware is being developed to run the software, the algorithm will be valid at steady-state and transient conditions, and will take advantage of the on-line learning capability of neural networks. Future plans include testing the neural network software and hardware prototype against an aircraft engine simulation. In this paper, the proposed neural network software and hardware is described and preliminary neural network training results are presented.

Further validation of artificial neural network-based emissions simulation models for conventional and hybrid electric vehicles.

PubMed

Tóth-Nagy, Csaba; Conley, John J; Jarrett, Ronald P; Clark, Nigel N

2006-07-01

With the advent of hybrid electric vehicles, computer-based vehicle simulation becomes more useful to the engineer and designer trying to optimize the complex combination of control strategy, power plant, drive train, vehicle, and driving conditions. With the desire to incorporate emissions as a design criterion, researchers at West Virginia University have developed artificial neural network (ANN) models for predicting emissions from heavy-duty vehicles. The ANN models were trained on engine and exhaust emissions data collected from transient dynamometer tests of heavy-duty diesel engines then used to predict emissions based on engine speed and torque data from simulated operation of a tractor truck and hybrid electric bus. Simulated vehicle operation was performed with the ADVISOR software package. Predicted emissions (carbon dioxide [CO2] and oxides of nitrogen [NO(x)]) were then compared with actual emissions data collected from chassis dynamometer tests of similar vehicles. This paper expands on previous research to include different driving cycles for the hybrid electric bus and varying weights of the conventional truck. Results showed that different hybrid control strategies had a significant effect on engine behavior (and, thus, emissions) and may affect emissions during different driving cycles. The ANN models underpredicted emissions of CO2 and NO(x) in the case of a class-8 truck but were more accurate as the truck weight increased.

An application of holographic interferometry for dynamic vibration analysis of a jet engine turbine compressor rotor

NASA Astrophysics Data System (ADS)

Fein, Howard

2003-09-01

Holographic Interferometry has been successfully employed to characterize the materials and behavior of diverse types of structures under dynamic stress. Specialized variations of this technology have also been applied to define dynamic and vibration related structural behavior. Such applications of holographic technique offer some of the most effective methods of modal and dynamic analysis available. Real-time dynamic testing of the modal and mechanical behavior of jet engine turbine, rotor, vane, and compressor structures has always required advanced instrumentation for data collection in either simulated flight operation test or computer-based modeling and simulations. Advanced optical holography techniques are alternate methods which result in actual full-field behavioral data in a noninvasive, noncontact environment. These methods offer significant insight in both the development and subsequent operational test and modeling of advanced jet engine turbine and compressor rotor structures and their integration with total vehicle system dynamics. Structures and materials can be analyzed with very low amplitude excitation and the resultant data can be used to adjust the accuracy of mathematically derived structural and behavioral models. Holographic Interferometry offers a powerful tool to aid in the developmental engineering of turbine rotor and compressor structures for high stress applications. Aircraft engine applications in particular most consider operational environments where extremes in vibration and impulsive as well as continuous mechanical stress can affect both operation and structural stability. These considerations present ideal requisites for analysis using advanced holographic methods in the initial design and test of turbine rotor components. Holographic techniques are nondestructive, real-time, and definitive in allowing the identification of vibrational modes, displacements, and motion geometries. Such information can be crucial to the determination of mechanical configurations and designs as well as critical operational parameters of turbine structural components or unit turbine components fabricated from advanced and exotic new materials or using new fabrication methods. Anomalous behavioral characteristics can be directly related to hidden structural or mounting anomalies and defects.

The Insertion of Human Factors Concerns into NextGen Programmatic Decisions

NASA Technical Reports Server (NTRS)

Beard, Bettina L.; Holbrook, Jon Brian; Seely, Rachel

2013-01-01

Since the costs of proposed improvements in air traffic management exceed available funding, FAA decision makers must select and prioritize what actually gets implemented. We discuss a set of methods to help forecast operational and human performance issues and benefits before new automation is introduced. This strategy could minimize the impact of politics, assist decision makers in selecting and prioritizing potential improvements, make the process more transparent and strengthen the link between the engineering and human factors domains.

Nitrogen oxide emission calculation for post-Panamax container ships by using engine operation power probability as weighting factor: A slow-steaming case.

PubMed

Cheng, Chih-Wen; Hua, Jian; Hwang, Daw-Shang

2018-06-01

In this study, the nitrogen oxide (NO x ) emission factors and total NO x emissions of two groups of post-Panamax container ships operating on a long-term slow-steaming basis along Euro-Asian routes were calculated using both the probability density function of engine power levels and the NO x emission function. The main engines of the five sister ships in Group I satisfied the Tier I emission limit stipulated in MARPOL (International Convention for the Prevention of Pollution from Ships) Annex VI, and those in Group II satisfied the Tier II limit. The calculated NO x emission factors of the Group I and Group II ships were 14.73 and 17.85 g/kWhr, respectively. The total NO x emissions of the Group II ships were determined to be 4.4% greater than those of the Group I ships. When the Tier II certification value was used to calculate the average total NO x emissions of Group II engines, the result was lower than the actual value by 21.9%. Although fuel consumption and carbon dioxide (CO 2 ) emissions were increased by 1.76% because of slow steaming, the NO x emissions were markedly reduced by 17.2%. The proposed method is more effective and accurate than the NO x Technical Code 2008. Furthermore, it can be more appropriately applied to determine the NO x emissions of international shipping inventory. The usage of operating power probability density function of diesel engines as the weighting factor and the NO x emission function obtained from test bed for calculating NO x emissions is more accurate and practical. The proposed method is suitable for all types and purposes of diesel engines, irrespective of their operating power level. The method can be used to effectively determine the NO x emissions of international shipping and inventory applications and should be considered in determining the carbon tax to be imposed in the future.

Development and training of a learning expert system in an autonomous mobile robot via simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spelt, P.F.; Lyness, E.; DeSaussure, G.

1989-11-01

The Center for Engineering Systems Advanced Research (CESAR) conducts basic research in the area of intelligent machines. Recently at CESAR a learning expert system was created to operate on board an autonomous robot working at a process control panel. The authors discuss two-computer simulation system used to create, evaluate and train this learning system. The simulation system has a graphics display of the current status of the process being simulated, and the same program which does the simulating also drives the actual control panel. Simulation results were validated on the actual robot. The speed and safety values of using amore » computerized simulator to train a learning computer, and future uses of the simulation system, are discussed.« less

Response to actual and simulated recordings of conventional takeoff and landing jet aircraft

NASA Technical Reports Server (NTRS)

Mabry, J. E.; Sullivan, B. M.

1978-01-01

Comparability between noise characteristics of synthesized recordings of aircraft in flight and actual recordings were investigated. Although the synthesized recordings were more smoothly time-varying than the actual recordings and the synthesizer could not produce a comb-filter effect that was present in the actual recordings, results supported the conclusion that annoyance response is comparable to the synthesized and actual recordings. A correction for duration markedly improved the validity of engineering calculation procedures designed to measure noise annoyance. Results led to the conclusion that the magnitude estimation psychophysical method was a highly reliable approach for evaluating engineering calculation procedures designed to measure noise annoyance. For repeated presentations of pairs of actual recordings, differences between judgment results for identical signals ranged from 0.0 to 0.5 db.

Prediction of wastewater treatment plants performance based on artificial fish school neural network

NASA Astrophysics Data System (ADS)

Zhang, Ruicheng; Li, Chong

2011-10-01

A reliable model for wastewater treatment plant is essential in providing a tool for predicting its performance and to form a basis for controlling the operation of the process. This would minimize the operation costs and assess the stability of environmental balance. For the multi-variable, uncertainty, non-linear characteristics of the wastewater treatment system, an artificial fish school neural network prediction model is established standing on actual operation data in the wastewater treatment system. The model overcomes several disadvantages of the conventional BP neural network. The results of model calculation show that the predicted value can better match measured value, played an effect on simulating and predicting and be able to optimize the operation status. The establishment of the predicting model provides a simple and practical way for the operation and management in wastewater treatment plant, and has good research and engineering practical value.

Ranking protective coatings: Laboratory vs. field experience

NASA Astrophysics Data System (ADS)

Conner, Jeffrey A.; Connor, William B.

1994-12-01

Environmentally protective coatings are used on a wide range of gas turbine components for survival in the harsh operating conditions of engines. A host of coatings are commercially available to protect hot-section components, ranging from simple aluminides to designer metallic overlays and ceramic thermal barrier coatings. A variety of coating-application processes are available, and they range from simple pack cementation processing to complex physical vapor deposition, which requires multimillion dollar facilities. Detailed databases are available for most coatings and coating/process combinations for a range of laboratory tests. Still, the analysis of components actually used in engines often yields surprises when compared against predicted coating behavior from laboratory testing. This paper highlights recent work to develop new laboratory tests that better simulate engine environments. Comparison of in-flight coating performance as well as industrial and factory engine testing on a range of hardware is presented along with laboratory predictions from standard testing and from recently developed cyclic burner-rig testing.

Performance Evaluation of Particle Sampling Probes for Emission Measurements of Aircraft Jet Engines

NASA Technical Reports Server (NTRS)

Lee, Poshin; Chen, Da-Ren; Sanders, Terry (Technical Monitor)

2001-01-01

Considerable attention has been recently received on the impact of aircraft-produced aerosols upon the global climate. Sampling particles directly from jet engines has been performed by different research groups in the U.S. and Europe. However, a large variation has been observed among published data on the conversion efficiency and emission indexes of jet engines. The variation results surely from the differences in test engine types, engine operation conditions, and environmental conditions. The other factor that could result in the observed variation is the performance of sampling probes used. Unfortunately, it is often neglected in the jet engine community. Particle losses during the sampling, transport, and dilution processes are often not discussed/considered in literatures. To address this issue, we evaluated the performance of one sampling probe by challenging it with monodisperse particles. A significant performance difference was observed on the sampling probe evaluated under different temperature conditions. Thermophoretic effect, nonisokinetic sampling and turbulence loss contribute to the loss of particles in sampling probes. The results of this study show that particle loss can be dramatic if the sampling probe is not well designed. Further, the result allows ones to recover the actual size distributions emitted from jet engines.

Experimental quiet engine program aerodynamic performance of Fan B

NASA Technical Reports Server (NTRS)

Giffin, R. G.; Parker, D. E.; Dunbar, L. W.

1972-01-01

This report presents the aerodynamic component test results of Fan B, one of two high-bypass-ratio, 1160 feet per second (353.6 m/sec) single-stage fans, which was designed and tested as part of the NASA Experimental Quiet Engine Program. The fan was designed to deliver a bypass pressure ratio of 1.50 with an adiabatic efficiency of 87.0% at a total fan flow of 950 lb/sec (430.9 kg/sec). It was tested with and without inlet distortion. A bypass total pressure ratio of 1.52 and an adiabatic efficiency of 86.9% at a total fan flow of 966 lb/sec (438.2 kg/sec) were actually achieved. An operating margin of 19.5% was demonstrated at design speed.

Advanced airbreathing engine lubricants study with a tetraester fluid and a synthetic paraffinic oil at 492 K (425 F)

NASA Technical Reports Server (NTRS)

Zaretsky, E. V.; Bamberger, E. N.

1972-01-01

Groups of 120-mm-bore angular-contact ball bearings made from AISI M-50 steel were fatigue tested with a tetraester and a synthetic paraffinic oil at a bearing temperature of 492 K (425 F) in an air environment. Bearing life exceeded AFBMA-predicted (catalog) life by factors in excess of 4 and 10 for the tetraester and synthetic paraffinic fluids, respectively. The final viscosities after 500 hours of operation were 14 and 6 times the initial values, respectively. During the same time period, when the test oil is replaced at a rate approximating the replenishment rate in actual commerical engine usage, no significant increase in lubricant viscosity with time was observed.

Flow Characterization and Dynamic Analysis of a Radial Compressor with Passive Method of Surge Control

NASA Astrophysics Data System (ADS)

Guillou, Erwann

Due to recent emission regulations, the use of turbochargers for force induction of internal combustion engines has increased. Actually, the trend in diesel engines is to downsize the engine by use of turbochargers that operate at higher pressure ratio. Unfortunately, increasing the rotational speed tends to reduce the turbocharger radial compressor range of operation which is limited at low mass flow rate by the occurrence of surge. In order to extent the operability of turbochargers, compressor housings can be equipped with a passive surge control device also known as ported shroud. This specific casing treatment has been demonstrated to enhance surge margin with minor negative impact on the compressor efficiency. However, the actual working mechanisms of the bypass system remain not well understood. In order to optimize the design of the ported shroud, it is then crucial to identify the dynamic flow changes induced by the implementation of the device to control instabilities. Experimental methods were used to assess the development of instabilities from stable, stall and eventually surge regimes of a ported shroud centrifugal compressor. Systematic comparison was conducted with the same compressor design without ported shroud. Hence, the full pressure dynamic survey of both compressors' performance characteristics converged toward two different and probably interrelated driving mechanisms to the development and/or propagation of unsteadiness within each compressor. One related the pressure disturbances at the compressor inlet, and notably the more apparent development of perturbations in the non-ported compressor impeller, whereas the other was attributed to the pressure distortions induced by the presence of the tongue in the asymmetric design of the compressor volute. Specific points of operation were selected to carry out planar flow measurements. At normal working, both standard and stereoscopic particle imaging velocimetry (PIV) measurements were performed to calculate the instantaneous and mean velocity fields at the inlet of the compressor. At incipient and full surge, phase-locked PIV measurements were added. In this work, satisfying characterization of the compressor inlet flow instabilities was obtained at different operational speeds. Combining transient pressure data and PIV measurements, the time evolution of the complex flow patterns occurring at surge was reconstructed and a better insight into the bypass mechanisms was achieved.

T55-L-712 turbine engine compressor housing refurbishment-plasma spray project

NASA Technical Reports Server (NTRS)

Leissler, George W.; Yuhas, John S.

1988-01-01

A study was conducted to assess the feasibility of reclaiming T55-L-712 turbine engine compressor housings with an 88 wt percent aluminum to 12 wt percent silicon alloy applied by a plasma spray process. Tensile strength testing was conducted on as-sprayed and thermally cycled test specimens which were plasma sprayed with 0.020 to 0.100 in. coating thicknesses. Satisfactory tensile strength values were observed in the as-sprayed tensile specimens. There was essentially no decrease in tensile strength after thermally cycling the tensile specimens. Furthermore, compressor housings were plasma sprayed and thermally cycled in a 150-hr engine test and a 200-hr actual flight test during which the turbine engine was operated at a variety of loads, speeds and torques. The plasma sprayed coating system showed no evidence of degradation or delamination from the compressor housings. As a result of these tests, a procedure was designed and developed for the application of an aluminum-silicon alloy in order to reclaim T55-L-712 turbine engine compressor housings.

25 CFR 39.201 - Does ISEF reflect the actual cost of school operations?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Does ISEF reflect the actual cost of school operations... Does ISEF reflect the actual cost of school operations? ISEF does not attempt to assess the actual cost of school operations either at the local school level or in the aggregate nationally. ISEF is a...

25 CFR 39.101 - Does ISEF assess the actual cost of school operations?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Does ISEF assess the actual cost of school operations? 39... SCHOOL EQUALIZATION PROGRAM Indian School Equalization Formula § 39.101 Does ISEF assess the actual cost of school operations? No. ISEF does not attempt to assess the actual cost of school operations either...

The performance and application of high speed long life LH2 hybrid bearings for reusable rocket engine turbomachinery

NASA Technical Reports Server (NTRS)

Hannum, N. P.; Nielson, C. E.

1983-01-01

Data are presented for two different experimental programs which were conducted to investigate the characteristics of a hybrid (hydrostatic/ball) bearing operating in liquid hydrogen. The same bearing design was used in both programs. Analytical predictions were made of the bearing characteristics and are compared with the experimental results when possible. The first program used a bearing tester to determine the steady state, transient, and cyclic life characteristics of the bearing over a wide range of operating conditions. The second program demonstrated the feasibility of applying hybrid bearings to an actual high speed turbopump by retrofitting and then testing an existing liquid hydrogen turbopump with the bearings.

Surface operators from M -strings

NASA Astrophysics Data System (ADS)

Mori, Hironori; Sugimoto, Yuji

2017-01-01

It has been found that surface operators have a significant role in Alday-Gaiotto-Tachikawa (AGT) relation. This duality is an outstanding consequence of M -theory, but it is actually encoded into the brane web for which the topological string can work. From this viewpoint, the surface defect in AGT relation is geometrically engineered as a toric brane realization. Also, there is a class of the brane configuration in M -theory called M -strings which can be translated into the language of the topological string. In this work, we propose a new M -string configuration which can realize AGT relation in the presence of the surface defect by utilizing the geometric transition in the refined topological string.

Managing the equipment service life in rendering engineering support to NPP operation

NASA Astrophysics Data System (ADS)

Ryasnyy, S. I.

2015-05-01

Apart from subjecting metal to nondestructive testing and determining its actual state, which are the traditional methods used for managing the service life of NPP equipment during its operation, other approaches closely linked with rendering engineering support to NPP operation have emerged in recent decades, which, however, have been covered in publications to a lesser extent. Service life management matters occupy the central place in the structure of engineering support measures. Application of the concept of repairing NPP equipment based on assessing its technical state and the risk of its failure makes it possible to achieve significantly smaller costs for maintenance and repairs and produce a larger amount of electricity due to shorter planned outages. Decreasing the occurrence probability of a process-related abnormality through its prediction is a further development of techniques for monitoring the technical state of equipment and systems. The proposed and implemented procedure for predicting the occurrence of process-related deviations from normal NPP operation opens the possibility to record in the online mode the trends in changes of process parameters that are likely to lead to malfunctions in equipment operation and to reduce the probability of power unit unloading when an abnormal technical state of equipment occurs and develops by recording changes in the state at an early stage and taking timely corrective measures. The article presents the structure of interconnections between the objectives and conditions of adjustment and commissioning tests, in which the management of equipment service life (saving and optimizing the service life) occupies the central place. Special attention is paid to differences in resource saving and optimization measures.

An integrated tool to support engineers for WMSDs risk assessment during the assembly line balancing.

PubMed

Di Benedetto, Raffaele; Fanti, Michele

2012-01-01

This paper wants to present an integrated approach to Line Balancing and Risk Assessment and a Software Tool named ErgoAnalysis that makes it easy to control the whole production process and produces a Risk Index for the actual work tasks in an Assembly Line. Assembly Line Balancing, or simply Line Balancing, is the problem of assigning operations to workstations along an assembly line, in such a way that the assignment be optimal in some sense. Assembly lines are characterized by production constraints and restrictions due to several aspects such as the nature of the product and the flow of orders. To be able to respond effectively to the needs of production, companies need to frequently change the workload and production models. Each manufacturing process might be quite different from another. To optimize very specific operations, assembly line balancing might utilize a number of methods and the Engineer must consider ergonomic constraints, in order to reduce the risk of WMDSs. Risk Assessment may result very expensive because the Engineer must evaluate it at every change. ErgoAnalysis can reduce cost and improve effectiveness in Risk Assessment during the Line Balancing.

Active Combustion Control for Aircraft Gas-Turbine Engines-Experimental Results for an Advanced, Low-Emissions Combustor Prototype

NASA Technical Reports Server (NTRS)

DeLaat, John C.; Kopasakis, George; Saus, Joseph R.; Chang, Clarence T.; Wey, Changlie

2012-01-01

Lean combustion concepts for aircraft engine combustors are prone to combustion instabilities. Mitigation of instabilities is an enabling technology for these low-emissions combustors. NASA Glenn Research Center s prior activity has demonstrated active control to suppress a high-frequency combustion instability in a combustor rig designed to emulate an actual aircraft engine instability experience with a conventional, rich-front-end combustor. The current effort is developing further understanding of the problem specifically as applied to future lean-burning, very low-emissions combustors. A prototype advanced, low-emissions aircraft engine combustor with a combustion instability has been identified and previous work has characterized the dynamic behavior of that combustor prototype. The combustor exhibits thermoacoustic instabilities that are related to increasing fuel flow and that potentially prevent full-power operation. A simplified, non-linear oscillator model and a more physics-based sectored 1-D dynamic model have been developed to capture the combustor prototype s instability behavior. Utilizing these models, the NASA Adaptive Sliding Phasor Average Control (ASPAC) instability control method has been updated for the low-emissions combustor prototype. Active combustion instability suppression using the ASPAC control method has been demonstrated experimentally with this combustor prototype in a NASA combustion test cell operating at engine pressures, temperatures, and flows. A high-frequency fuel valve was utilized to perturb the combustor fuel flow. Successful instability suppression was shown using a dynamic pressure sensor in the combustor for controller feedback. Instability control was also shown with a pressure feedback sensor in the lower temperature region upstream of the combustor. It was also demonstrated that the controller can prevent the instability from occurring while combustor operation was transitioning from a stable, low-power condition to a normally unstable high-power condition, thus enabling the high-power condition.

Similarity constraints in testing of cooled engine parts

NASA Technical Reports Server (NTRS)

Colladay, R. S.; Stepka, F. S.

1974-01-01

A study is made of the effect of testing cooled parts of current and advanced gas turbine engines at the reduced temperature and pressure conditions which maintain similarity with the engine environment. Some of the problems facing the experimentalist in evaluating heat transfer and aerodynamic performance when hardware is tested at conditions other than the actual engine environment are considered. Low temperature and pressure test environments can simulate the performance of actual size prototype engine hardware within the tolerance of experimental accuracy if appropriate similarity conditions are satisfied. Failure to adhere to these similarity constraints because of test facility limitations or other reasons, can result in a number of serious errors in projecting the performance of test hardware to engine conditions.

Nonlinear rotordynamics analysis. [Space Shuttle Main Engine turbopumps

NASA Technical Reports Server (NTRS)

Noah, Sherif T.

1991-01-01

Effective analysis tools were developed for predicting the nonlinear rotordynamic behavior of the Space Shuttle Main Engine (SSME) turbopumps under steady and transient operating conditions. Using these methods, preliminary parametric studies were conducted on both generic and actual HPOTP (high pressure oxygen turbopump) models. In particular, a novel modified harmonic balance/alternating Fourier transform (HB/AFT) method was developed and used to conduct a preliminary study of the effects of fluid, bearing and seal forces on the unbalanced response of a multi-disk rotor in the presence of bearing clearances. The method makes it possible to determine periodic, sub-, super-synchronous and chaotic responses of a rotor system. The method also yields information about the stability of the obtained response, thus allowing bifurcation analyses. This provides a more effective capability for predicting the response under transient conditions by searching in proximity of resonance peaks. Preliminary results were also obtained for the nonlinear transient response of an actual HPOTP model using an efficient, newly developed numerical method based on convolution integration. Currently, the HB/AFT is being extended for determining the aperiodic response of nonlinear systems. Initial results show the method to be promising.

Surrogate measures: A proposed alternative in human factors assessment of operational measures of performance

NASA Technical Reports Server (NTRS)

Kennedy, Robert S.; Lane, Norman E.; Kuntz, Lois A.

1987-01-01

Surrogate measures are proposed as an alternative to direct assessment of operational performance for purposes of screening agents who may have to work under unusual stresses or in exotic environments. Such measures are particularly proposed when the surrogate can be empirically validated against the operational criterion. The focus is on cognitive (or throughput) performances in humans as opposed to sensory (input) or motor (output) measures, but the methods should be applicable for development of batteries which will tap input/output functions. A menu of performance tasks is under development for implementation on a battery-operated portable microcomputer, with 21 tests currently available. The tasks are reliable and become stable in minimum amounts of time; appear sensitive to some agents; comprise constructs related to actual job tasks; and are easily administered in most environments. Implications for human factors engineering studies in environmental stress are discussed.

Flight Investigation of the Cooling Characteristics of a Two-row Radial Engine Installation III : Engine Temperature Distribution

NASA Technical Reports Server (NTRS)

Rennak, Robert M; Messing, Wesley E; Morgan, James E

1946-01-01

The temperature distribution of a two-row radial engine in a twin-engine airplane has been investigated in a series of flight tests. The test engine was operated over a wide range of conditions at density altitudes of 5000 and 20,000 feet; quantitative results are presented showing the effects of flight and engine variables upon average engine temperature and over-all temperature spread. Discussions of the effect of the variables on the shape of the temperature patterns and on the temperature distribution of individual cylinders are also included. The results indicate that, for the tests conducted, the temperature distribution patterns were chiefly determined by the fuel-air ratio and cooling-air distributions. It was possible to calculate individual cylinder temperature, on the assumption of equal power distribution among cylinders, to within an average of plus or minus 14 degrees F. of the actual temperature. A considerable change occurred in either the spread or the thrust axis, the average engine fuel-air ratio, the engine speed, the power, or the blower ratio. Smaller effects on the temperature pattern were noticed with a change in cowl-flap opening and altitude. In most of the tests, a change in conditions affected the temperature of the barrels less than that of the heads. The variation of flight and engine variables had a negligible effect on the temperature distributions of the individual cylinders. (author)

Investigation of the Reverse Water Gas Shift Reaction for Production of Oxygen From Mars Atmospheric Carbon Dioxide

NASA Technical Reports Server (NTRS)

Meyer, Tom; Zubrin, Robert

1997-01-01

The first phase of the research includes a comprehensive analytical study examining the potential applications for engineering subsystems and mission strategies made possible by such RWGS based subsystems, and will include an actual experimental demonstration and performance characterization of a full-scale brassboard RWGS working unit. By the time of this presentation the laboratory demonstration unit will not yet be operational but we will present the results of our analytical studies to date and plans for the ongoing work.

Cryogenic Thermal Performance Testing of Bulk-Fill and Aerogel Insulation Materials

NASA Astrophysics Data System (ADS)

Scholtens, B. E.; Fesmire, J. E.; Sass, J. P.; Augustynowicz, S. D.; Heckle, K. W.

2008-03-01

Thermal conductivity testing under actual-use conditions is a key to understanding how cryogenic thermal insulation systems perform in regard to engineering, economics, and materials factors. The Cryogenics Test Laboratory at NASA's Kennedy Space Center tested a number of bulk-fill insulation materials, including aerogel beads, glass bubbles, and perlite powder, using a new cylindrical cryostat. Boundary temperatures for the liquid nitrogen boiloff method were 78 K and 293 K. Tests were performed as a function of cold vacuum pressure under conditions ranging from high vacuum to no vacuum. Results were compared with those from complementary test methods in the range of 20 K to 300 K. Various testing techniques are required to completely understand the operating performance of a material and to provide data for answers to design engineering questions.

HSR combustion analytical research

NASA Technical Reports Server (NTRS)

Nguyen, H. Lee

1992-01-01

Increasing the pressure and temperature of the engines of a new generation of supersonic airliners increases the emissions of nitrogen oxides (NO(x)) to a level that would have an adverse impact on the Earth's protective ozone layer. In the process of evolving and implementing low emissions combustor technologies, NASA LeRC has pursued a combustion analysis code program to guide combustor design processes, to identify potential concepts of the greatest promise, and to optimize them at low cost, with short turnaround time. The computational analyses are evaluated at actual engine operating conditions. The approach is to upgrade and apply advanced computer programs for gas turbine applications. Efforts were made in further improving the code capabilities for modeling the physics and the numerical methods of solution. Then test cases and measurements from experiments are used for code validation.

Aspects of remote maintenance in an FRG reprocessing plant from the manufacturer's viewpoint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zeitzchel, G.; Tennie, M.; Saal, G.

In April 1986 a consortium led by Kraftwerk Union AG was commissioned by the German society for nuclear fuel reprocessing (DWK) to build the first West German commercial reprocessing plant for spent fuel assemblies. The main result of the planning efforts regarding remote maintenance operations inside the main process building was the introduction of FEMO technology (FEMO is an acronym based on German for remote handling modular technique). According to this technology the two cells in which the actual reprocessing (which is based on the PUREX technique) takes place are provided with frames to accommodate the process components (tanks, pumps,more » agitators, etc.), each frame together with the components which it supports forming one module. The two cells are inaccessible and windowless. For handling operations each cell is equipped with an overhead crane and a crane-like manipulator carrier system (MTS) with power manipulator. Viewing of the operations from outside the cells is made possible by television (TV) cameras installed at the crane, the MTS, and the manipulator. This paper addresses some examples of problems that still need to be solved in connection with FEMO handling. In particular, the need for close cooperation between the equipment operator, the component designer, the process engineer, the planning engineer, and the licensing authorities will be demonstrated.« less

Extended device profiles and testing procedures for the approval process of integrated medical devices using the IEEE 11073 communication standard.

PubMed

Janß, Armin; Thorn, Johannes; Schmitz, Malte; Mildner, Alexander; Dell'Anna-Pudlik, Jasmin; Leucker, Martin; Radermacher, Klaus

2018-02-23

Nowadays, only closed and proprietary integrated operating room systems (IORS) from big manufacturers are available on the market. Hence, the interconnection of components from third-party vendors is only possible with increased time and costs. In the context of the German Federal Ministry of Education and Research (BMBF)-funded project OR.NET (2012-2016), the open integration of medical devices from different manufacturers was addressed. An integrated operating theater based on the open communication standard IEEE 11073 shall give clinical operators the opportunity to choose medical devices independently of the manufacturer. This approach would be advantageous especially for hospital operators and small- and medium-sized enterprises (SME) of medical devices. Actual standards and concepts regarding technical feasibility and the approval process do not cope with the requirements for a modular integration of medical devices in the operating room (OR), based on an open communication standard. Therefore, innovative approval strategies and corresponding certification and test procedures, which cover actual legal and normative standards, have to be developed in order to support the future risk management and the usability engineering process of open integrated medical devices in the OR. The use of standardized device and service profiles and a three-step testing procedure, including conformity, interoperability and integration tests are described in this paper and shall support the manufacturers to integrate their medical devices without disclosing the medical devices' risk analysis and related confidential expertise or proprietary information.

Teleoperator Human Factors Study

NASA Technical Reports Server (NTRS)

1986-01-01

An investigation of the spectrum of space teleoperation activities likely in the 1985 to 1995 decade focused on the resolution of critical human engineering issues and characterization of the technology effect on performance of remote human operators. The study began with the identification and documentation of a set of representative reference teleoperator tasks. For each task, technology, development, and design options, issues, and alternatives that bear on human operator performance were defined and categorized. A literature survey identified existing studies of man/machine issues. For each teleoperations category, an assessment was made of the state of knowledge on a scale from adequate to void. The tests, experiments, and analyses necessary to provide the missing elements of knowledge were then defined. A limited set of tests were actually performed, including operator selection, baseline task definition, control mode study, lighting study, camera study, and preliminary time delay study.

The X-43A Flight Research Program: Lessons Learned on the Road to Mach 10

NASA Technical Reports Server (NTRS)

Peebles, Curtis

2007-01-01

During an aerospace engineer's undergraduate studies, he or she will attend classes in aerodynamics, thermodynamics, structures, stability and control, dynamics, design, propulsion, and computer science, along with the related courses in mathematics, physics, statistics, and chemistry required to understand the material. Upon graduation, the new engineer will have acquired a basic knowledge of how to build an aerospace vehicle. What only comes through experience, however, is the understanding of the inevitable imperfect process through which an aerospace vehicle is built. This is the adventure of turning a basic concept into functional hardware. Engineers working on a project must often deal with ambiguous situations. They are routinely asked by management to provide risk assessments of a project, yet even after careful analysis uncertainties remain. The project must be accomplished within finite limits of time and money. The question an engineer answers is whether the solution to potential problem is worth the cost and schedule delay, or if the solution might actually be worse than the problem it is meant to solve. Review protocols are established to ensure that an unknown has not been overlooked. But these cannot protect against an unknown unknown. Examples of these situations can be found in the history of the X-43A Hyper-X (Hypersonic Experiment) program. In this NASA project, a supersonic combustion ramjet (scramjet) engine was flight tested on a subscale vehicle. The X-43A Hyper-X Research Vehicle (HXRV) was launched from a B-52B mothership, then boosted to the test speed by a modified Pegasus rocket first stage, called the Hyper-X Launch Vehicle (HXLV). Once at the proper speed and altitude, the X-43A separated from the booster, stabilized itself, and then the engine test began. Although wind-tunnel scramjet engine tests had begun in the late 1950s, before the Hyper-X program there had never been an actual in-flight test of such an engine integrated with an appropriate airframe. Thus, while the scramjet had successfully operated in the artificial airflow of wind tunnels, the concept had yet to be proven in real air. These conditions meant changes in density and temperature, as well as changes in angle of attack and sideslip of a free-flying vehicle. A wind tunnel is limited in its ability to simulate these subtle factures, which have a major impact on almost any vehicle, but especially that of a scramjet's performance. The Hyper-X project was to provide a real-world benchmark of the ground test data. The full scale X-43A engine would be operated in the wind tunnel, and then flown, and the data from its operation would then be compared with projections. If these matched, the wind tunnel data would be considered a reliable design tool for future scramjet. If there were significant differences, the reasons for these would have to be identified. Until such information was available, scramjets would lack the technological maturity to be considered for future space launch or high-speed atmospheric flight vehicles.

Virtual manufacturing work cell for engineering

NASA Astrophysics Data System (ADS)

Watanabe, Hideo; Ohashi, Kazushi; Takahashi, Nobuyuki; Kato, Kiyotaka; Fujita, Satoru

1997-12-01

The life cycles of products have been getting shorter. To meet this rapid turnover, manufacturing systems must be frequently changed as well. In engineering to develop manufacturing systems, there are several tasks such as process planning, layout design, programming, and final testing using actual machines. This development of manufacturing systems takes a long time and is expensive. To aid the above engineering process, we have developed the virtual manufacturing workcell (VMW). This paper describes a concept of VMW and design method through computer aided manufacturing engineering using VMW (CAME-VMW) related to the above engineering tasks. The VMW has all design data, and realizes a behavior of equipment and devices using a simulator. The simulator has logical and physical functionality. The one simulates a sequence control and the other simulates motion control, shape movement in 3D space. The simulator can execute the same control software made for actual machines. Therefore we can verify the behavior precisely before the manufacturing workcell will be constructed. The VMW creates engineering work space for several engineers and offers debugging tools such as virtual equipment and virtual controllers. We applied this VMW to development of a transfer workcell for vaporization machine in actual manufacturing system to produce plasma display panel (PDP) workcell and confirmed its effectiveness.

Analyzing system safety in lithium-ion grid energy storage

NASA Astrophysics Data System (ADS)

Rosewater, David; Williams, Adam

2015-12-01

As grid energy storage systems become more complex, it grows more difficult to design them for safe operation. This paper first reviews the properties of lithium-ion batteries that can produce hazards in grid scale systems. Then the conventional safety engineering technique Probabilistic Risk Assessment (PRA) is reviewed to identify its limitations in complex systems. To address this gap, new research is presented on the application of Systems-Theoretic Process Analysis (STPA) to a lithium-ion battery based grid energy storage system. STPA is anticipated to fill the gaps recognized in PRA for designing complex systems and hence be more effective or less costly to use during safety engineering. It was observed that STPA is able to capture causal scenarios for accidents not identified using PRA. Additionally, STPA enabled a more rational assessment of uncertainty (all that is not known) thereby promoting a healthy skepticism of design assumptions. We conclude that STPA may indeed be more cost effective than PRA for safety engineering in lithium-ion battery systems. However, further research is needed to determine if this approach actually reduces safety engineering costs in development, or improves industry safety standards.

Analysis and simulation of the I C engine Otto cycle using the second law of thermodynamics

NASA Astrophysics Data System (ADS)

Abdel-Rahim, Y. M.

The present investigation is an application of the second law of thermodynamics to the spark ignition engine cycle. A comprehensive thermodynamic analysis of the air standard cycle is conducted using the first and second laws of thermodynamics, the ideal gas equation of state and the perfect gas properties for air. The study investigates the effect of the cycle parameters on the cycle performance reflected by the first and second law efficiencies, the heat added, the work done, the available energy added as well as the history of the internal, available and unavailable energies along the cycle. The study shows that the second law efficiency is a function of the compression ratio, the initial temperature, the maximum temperature as well as the dead state temperature. A non-dimensional comprehensive thermodynamic simulation model for the actual Otto cycle is developed to study the effects of the design and operating parameters of the cycle on the cycle performance. The analysis takes into account engine geometry, mixture strength, heat transfer, piston motion, engine speed, mechanical friction, spark advance and combustion duration.

47 CFR 27.1202 - Cable/BRS cross-ownership.

Code of Federal Regulations, 2014 CFR

2014-10-01

... portion of the franchise area actually served by the cable operator's cable system and the cable operator... franchise area actually served by the cable operator's cable system the cable operator will use the BRS... that no portion of the GSA of the BRS station is within the portion of the franchise area actually...

47 CFR 27.1202 - Cable/BRS cross-ownership.

Code of Federal Regulations, 2011 CFR

2011-10-01

... portion of the franchise area actually served by the cable operator's cable system and the cable operator... franchise area actually served by the cable operator's cable system the cable operator will use the BRS... that no portion of the GSA of the BRS station is within the portion of the franchise area actually...

47 CFR 27.1202 - Cable/BRS cross-ownership.

Code of Federal Regulations, 2012 CFR

2012-10-01

... portion of the franchise area actually served by the cable operator's cable system and the cable operator... franchise area actually served by the cable operator's cable system the cable operator will use the BRS... that no portion of the GSA of the BRS station is within the portion of the franchise area actually...

47 CFR 27.1202 - Cable/BRS cross-ownership.

Code of Federal Regulations, 2013 CFR

2013-10-01

... portion of the franchise area actually served by the cable operator's cable system and the cable operator... franchise area actually served by the cable operator's cable system the cable operator will use the BRS... that no portion of the GSA of the BRS station is within the portion of the franchise area actually...

Modeling Commercial Turbofan Engine Icing Risk With Ice Crystal Ingestion

NASA Technical Reports Server (NTRS)

Jorgenson, Philip C. E.; Veres, Joseph P.

2013-01-01

The occurrence of ice accretion within commercial high bypass aircraft turbine engines has been reported under certain atmospheric conditions. Engine anomalies have taken place at high altitudes that have been attributed to ice crystal ingestion, partially melting, and ice accretion on the compression system components. The result was degraded engine performance, and one or more of the following: loss of thrust control (roll back), compressor surge or stall, and flameout of the combustor. As ice crystals are ingested into the fan and low pressure compression system, the increase in air temperature causes a portion of the ice crystals to melt. It is hypothesized that this allows the ice-water mixture to cover the metal surfaces of the compressor stationary components which leads to ice accretion through evaporative cooling. Ice accretion causes a blockage which subsequently results in the deterioration in performance of the compressor and engine. The focus of this research is to apply an engine icing computational tool to simulate the flow through a turbofan engine and assess the risk of ice accretion. The tool is comprised of an engine system thermodynamic cycle code, a compressor flow analysis code, and an ice particle melt code that has the capability of determining the rate of sublimation, melting, and evaporation through the compressor flow path, without modeling the actual ice accretion. A commercial turbofan engine which has previously experienced icing events during operation in a high altitude ice crystal environment has been tested in the Propulsion Systems Laboratory (PSL) altitude test facility at NASA Glenn Research Center. The PSL has the capability to produce a continuous ice cloud which are ingested by the engine during operation over a range of altitude conditions. The PSL test results confirmed that there was ice accretion in the engine due to ice crystal ingestion, at the same simulated altitude operating conditions as experienced previously in flight. The computational tool was utilized to help guide a portion of the PSL testing, and was used to predict ice accretion could also occur at significantly lower altitudes. The predictions were qualitatively verified by subsequent testing of the engine in the PSL. The PSL test has helped to calibrate the engine icing computational tool to assess the risk of ice accretion. The results from the computer simulation identified prevalent trends in wet bulb temperature, ice particle melt ratio, and engine inlet temperature as a function of altitude for predicting engine icing risk due to ice crystal ingestion.

Rover Sequencing and Visualization Program

NASA Technical Reports Server (NTRS)

Cooper, Brian; Hartman, Frank; Maxwell, Scott; Yen, Jeng; Wright, John; Balacuit, Carlos

2005-01-01

The Rover Sequencing and Visualization Program (RSVP) is the software tool for use in the Mars Exploration Rover (MER) mission for planning rover operations and generating command sequences for accomplishing those operations. RSVP combines three-dimensional (3D) visualization for immersive exploration of the operations area, stereoscopic image display for high-resolution examination of the downlinked imagery, and a sophisticated command-sequence editing tool for analysis and completion of the sequences. RSVP is linked with actual flight-code modules for operations rehearsal to provide feedback on the expected behavior of the rover prior to committing to a particular sequence. Playback tools allow for review of both rehearsed rover behavior and downlinked results of actual rover operations. These can be displayed simultaneously for comparison of rehearsed and actual activities for verification. The primary inputs to RSVP are downlink data products from the Operations Storage Server (OSS) and activity plans generated by the science team. The activity plans are high-level goals for the next day s activities. The downlink data products include imagery, terrain models, and telemetered engineering data on rover activities and state. The Rover Sequence Editor (RoSE) component of RSVP performs activity expansion to command sequences, command creation and editing with setting of command parameters, and viewing and management of rover resources. The HyperDrive component of RSVP performs 2D and 3D visualization of the rover s environment, graphical and animated review of rover-predicted and telemetered state, and creation and editing of command sequences related to mobility and Instrument Deployment Device (IDD) operations. Additionally, RoSE and HyperDrive together evaluate command sequences for potential violations of flight and safety rules. The products of RSVP include command sequences for uplink that are stored in the Distributed Object Manager (DOM) and predicted rover state histories stored in the OSS for comparison and validation of downlinked telemetry. The majority of components comprising RSVP utilize the MER command and activity dictionaries to automatically customize the system for MER activities. Thus, RSVP, being highly data driven, may be tailored to other missions with minimal effort. In addition, RSVP uses a distributed, message-passing architecture to allow multitasking, and collaborative visualization and sequence development by scattered team members.

Update on Rover Sequencing and Visualization Program

NASA Technical Reports Server (NTRS)

Cooper, Brian; Hartman, Frank; Maxwell, Scott; Yen, Jeng; Wright, John; Balacuit, Carlos

2005-01-01

The Rover Sequencing and Visualization Program (RSVP) has been updated. RSVP was reported in Rover Sequencing and Visualization Program (NPO-30845), NASA Tech Briefs, Vol. 29, No. 4 (April 2005), page 38. To recapitulate: The Rover Sequencing and Visualization Program (RSVP) is the software tool to be used in the Mars Exploration Rover (MER) mission for planning rover operations and generating command sequences for accomplishing those operations. RSVP combines three-dimensional (3D) visualization for immersive exploration of the operations area, stereoscopic image display for high-resolution examination of the downlinked imagery, and a sophisticated command-sequence editing tool for analysis and completion of the sequences. RSVP is linked with actual flight code modules for operations rehearsal to provide feedback on the expected behavior of the rover prior to committing to a particular sequence. Playback tools allow for review of both rehearsed rover behavior and downlinked results of actual rover operations. These can be displayed simultaneously for comparison of rehearsed and actual activities for verification. The primary inputs to RSVP are downlink data products from the Operations Storage Server (OSS) and activity plans generated by the science team. The activity plans are high-level goals for the next day s activities. The downlink data products include imagery, terrain models, and telemetered engineering data on rover activities and state. The Rover Sequence Editor (RoSE) component of RSVP performs activity expansion to command sequences, command creation and editing with setting of command parameters, and viewing and management of rover resources. The HyperDrive component of RSVP performs 2D and 3D visualization of the rover s environment, graphical and animated review of rover predicted and telemetered state, and creation and editing of command sequences related to mobility and Instrument Deployment Device (robotic arm) operations. Additionally, RoSE and HyperDrive together evaluate command sequences for potential violations of flight and safety rules. The products of RSVP include command sequences for uplink that are stored in the Distributed Object Manager (DOM) and predicted rover state histories stored in the OSS for comparison and validation of downlinked telemetry. The majority of components comprising RSVP utilize the MER command and activity dictionaries to automatically customize the system for MER activities.

Experimental performance of the regenerator for the Chrysler upgraded automotive gas turbine engine

NASA Technical Reports Server (NTRS)

Winter, J. M.; Nussle, R. C.

1982-01-01

Automobile gas turbine engine regenerator performance was studied in a regenerator test facility that provided a satisfactory simulation of the actual engine operating environment but with independent control of airflow and gas flow. Velocity and temperature distributions were measured immediately downstream of both the core high-pressure-side outlet and the core low-pressure-side outlet. For the original engine housing, the regenerator temperature effectiveness was 1 to 2 percent higher than the design value, and the heat transfer effectiveness was 2 to 4 percent lower than the design value over the range of test conditions simulating 50 to 100 percent of gas generator speed. Recalculating the design values to account for seal leakage decreased the design heat transfer effectiveness to values consistent with those measured herein. A baffle installed in the engine housing high-pressure-side inlet provided more uniform velocities out of the regenerator but did not improve the effectiveness. A housing designed to provide more uniform axial flow to the regenerator was also tested. Although temperature uniformity was improved, the effectiveness values were not improved. Neither did 50-percent flow blockage (90 degree segment) applied to the high-pressure-side inlet change the effectiveness significantly.

Calibrating thermal behavior of electronics

DOEpatents

Chainer, Timothy J.; Parida, Pritish R.; Schultz, Mark D.

2017-07-11

A method includes determining a relationship between indirect thermal data for a processor and a measured temperature associated with the processor, during a calibration process, obtaining the indirect thermal data for the processor during actual operation of the processor, and determining an actual significant temperature associated with the processor during the actual operation using the indirect thermal data for the processor during actual operation of the processor and the relationship.

Calibrating thermal behavior of electronics

DOEpatents

Chainer, Timothy J.; Parida, Pritish R.; Schultz, Mark D.

2016-05-31

A method includes determining a relationship between indirect thermal data for a processor and a measured temperature associated with the processor, during a calibration process, obtaining the indirect thermal data for the processor during actual operation of the processor, and determining an actual significant temperature associated with the processor during the actual operation using the indirect thermal data for the processor during actual operation of the processor and the relationship.

Calibrating thermal behavior of electronics

DOEpatents

Chainer, Timothy J.; Parida, Pritish R.; Schultz, Mark D.

2017-01-03

A method includes determining a relationship between indirect thermal data for a processor and a measured temperature associated with the processor, during a calibration process, obtaining the indirect thermal data for the processor during actual operation of the processor, and determining an actual significant temperature associated with the processor during the actual operation using the indirect thermal data for the processor during actual operation of the processor and the relationship.

SU-F-P-18: Development of the Technical Training System for Patient Set-Up Considering Rotational Correction in the Virtual Environment Using Three-Dimensional Computer Graphic Engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Imura, K; Fujibuchi, T; Hirata, H

Purpose: Patient set-up skills in radiotherapy treatment room have a great influence on treatment effect for image guided radiotherapy. In this study, we have developed the training system for improving practical set-up skills considering rotational correction in the virtual environment away from the pressure of actual treatment room by using three-dimensional computer graphic (3DCG) engine. Methods: The treatment room for external beam radiotherapy was reproduced in the virtual environment by using 3DCG engine (Unity). The viewpoints to perform patient set-up in the virtual treatment room were arranged in both sides of the virtual operable treatment couch to assume actual performancemore » by two clinical staffs. The position errors to mechanical isocenter considering alignment between skin marker and laser on the virtual patient model were displayed by utilizing numerical values expressed in SI units and the directions of arrow marks. The rotational errors calculated with a point on the virtual body axis as the center of each rotation axis for the virtual environment were corrected by adjusting rotational position of the body phantom wound the belt with gyroscope preparing on table in a real space. These rotational errors were evaluated by describing vector outer product operations and trigonometric functions in the script for patient set-up technique. Results: The viewpoints in the virtual environment allowed individual user to visually recognize the position discrepancy to mechanical isocenter until eliminating the positional errors of several millimeters. The rotational errors between the two points calculated with the center point could be efficiently corrected to display the minimum technique mathematically by utilizing the script. Conclusion: By utilizing the script to correct the rotational errors as well as accurate positional recognition for patient set-up technique, the training system developed for improving patient set-up skills enabled individual user to indicate efficient positional correction methods easily.« less

Solid rocket booster performance evaluation model. Volume 1: Engineering description

NASA Technical Reports Server (NTRS)

1974-01-01

The space shuttle solid rocket booster performance evaluation model (SRB-II) is made up of analytical and functional simulation techniques linked together so that a single pass through the model will predict the performance of the propulsion elements of a space shuttle solid rocket booster. The available options allow the user to predict static test performance, predict nominal and off nominal flight performance, and reconstruct actual flight and static test performance. Options selected by the user are dependent on the data available. These can include data derived from theoretical analysis, small scale motor test data, large motor test data and motor configuration data. The user has several options for output format that include print, cards, tape and plots. Output includes all major performance parameters (Isp, thrust, flowrate, mass accounting and operating pressures) as a function of time as well as calculated single point performance data. The engineering description of SRB-II discusses the engineering and programming fundamentals used, the function of each module, and the limitations of each module.

B-29 Superfortress with Ramjet Missile

NASA Image and Video Library

1948-08-21

The NACA’s Lewis Flight Propulsion Laboratory used a Boeing B‒29 Superfortress as a testbed for ramjet investigations in the late 1940s. Lewis researchers conducted a wide variety of studies on ramjets to determine basic the operational data necessary to design missiles. Extensive wind tunnel and test stand studies were augmented by actual flight tests. Lewis engineers modified this B‒29 so that the ramjet could be stored in the bomb bay. Once the aircraft reached the desired altitude and speed, a mechanical arm suspended the ramjet 52 inches below the bomb bay. The ramjet’s angle-of-attack could be independently adjusted, and a periscope permitted a view of the test article from inside the aircraft. Researchers took measurements in free-stream conditions at speeds up to Mach 0.51 and at altitudes ranging from 5,000 to 30,000 feet. They then shut the ramjet down and retracted it into the aircraft. The researchers first determined that 14,000 feet was the maximum altitude at which the engine could be ignited by spark. They used flares to start the engine at altitudes up to 30,000 feet. They were able to determine maximum combustion efficiencies, response time to changes in fuel flow, and minimum fuel-air ratios. Overall the ramjet operated well at all speeds and altitudes.

Mechanical Design of Spacecraft

NASA Technical Reports Server (NTRS)

1962-01-01

In the spring of 1962, engineers from the Engineering Mechanics Division of the Jet Propulsion Laboratory gave a series of lectures on spacecraft design at the Engineering Design seminars conducted at the California Institute of Technology. Several of these lectures were subsequently given at Stanford University as part of the Space Technology seminar series sponsored by the Department of Aeronautics and Astronautics. Presented here are notes taken from these lectures. The lectures were conceived with the intent of providing the audience with a glimpse of the activities of a few mechanical engineers who are involved in designing, building, and testing spacecraft. Engineering courses generally consist of heavily idealized problems in order to allow the more efficient teaching of mathematical technique. Students, therefore, receive a somewhat limited exposure to actual engineering problems, which are typified by more unknowns than equations. For this reason it was considered valuable to demonstrate some of the problems faced by spacecraft designers, the processes used to arrive at solutions, and the interactions between the engineer and the remainder of the organization in which he is constrained to operate. These lecture notes are not so much a compilation of sophisticated techniques of analysis as they are a collection of examples of spacecraft hardware and associated problems. They will be of interest not so much to the experienced spacecraft designer as to those who wonder what part the mechanical engineer plays in an effort such as the exploration of space.

Altitude Wind Tunnel Operating at Night

NASA Image and Video Library

1945-04-21

The Altitude Wind Tunnel (AWT) during one of its overnight runs at the National Advisory Committee for Aeronautics (NACA) Aircraft Engine Research Laboratory in Cleveland, Ohio. The AWT was run during night hours so that its massive power loads were handled when regional electric demands were lowest. At the time the AWT was among the most complex wind tunnels ever designed. In order to simulate conditions at high altitudes, NACA engineers designed innovative new systems that required tremendous amounts of electricity. The NACA had an agreement with the local electric company that it would run its larger facilities overnight when local demand was at its lowest. In return the utility discounted its rates for the NACA during those hours. The AWT could produce wind speeds up to 500 miles per hour through its 20-foot-diameter test section at the standard operating altitude of 30,000 feet. The airflow was created by a large fan that was driven by an 18,000-horsepower General Electric induction motor. The altitude simulation was accomplished by large exhauster and refrigeration systems. The cold temperatures were created by 14 Carrier compressors and the thin atmosphere by four 1750-horsepower exhausters. The first and second shifts usually set up and broke down the test articles, while the third shift ran the actual tests. Engineers would often have to work all day, then operate the tunnel overnight, and analyze the data the next day. The night crew usually briefed the dayshift on the tests during morning staff meetings.

Monitoring means for combustion engine electric storage battery means

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, G. K.; Rautiola, R. E.; Taylor, R. E.

Disclosed, in combination, are a combustion engine, an electric storage battery, an electrically powered starter motor for at times driving the engine in order to start the engine, and an electrical system monitor; the electrical system monitor has a first monitoring portion which senses the actual voltage across the battery and a second monitoring portion which monitors the current through the battery; an electrical switch controls associated circuitry and is actuatable into open or closed conditions; whenever the first monitoring portion senses a preselected magnitude of the actual voltage across the battery or the second monitoring portion senses a preselectedmore » magnitude of the current flow through the battery, the electrical switch is actuated.« less

Gas-Dynamic Designing of the Exhaust System for the Air Brake

NASA Astrophysics Data System (ADS)

Novikova, Yu; Goriachkin, E.; Volkov, A.

2018-01-01

Each gas turbine engine is tested some times during the life-cycle. The test equipment includes the air brake that utilizes the power produced by the gas turbine engine. In actual conditions, the outlet pressure of the air brake does not change and is equal to atmospheric pressure. For this reason, for the air brake work it is necessary to design the special exhaust system. Mission of the exhaust system is to provide the required level of backpressure at the outlet of the air brake. The backpressure is required for the required power utilization by the air brake (the air brake operation in the required points on the performance curves). The paper is described the development of the gas dynamic canal, designing outlet guide vane and the creation of a unified exhaust system for the air brake. Using a unified exhaust system involves moving the operating point to the performance curve further away from the calculated point. However, the applying of one exhaust system instead of two will significantly reduce the cash and time costs.

Automating CapCom: Pragmatic Operations and Technology Research for Human Exploration of Mars

NASA Technical Reports Server (NTRS)

Clancey, William J.

2003-01-01

During the Apollo program, NASA and the scientific community used terrestrial analog sites for understanding planetary features and for training astronauts to be scientists. More recently, computer scientists and human factors specialists have followed geologists and biologists into the field, learning how science is actually done on expeditions in extreme environments. Research stations have been constructed by the Mars Society in the Arctic and American southwest, providing facilities for hundreds of researchers to investigate how small crews might live and work on Mars. Combining these interests-science, operations, and technology-in Mars analog field expeditions provides tremendous synergy and authenticity to speculations about Mars missions. By relating historical analyses of Apollo and field science, engineers are creating experimental prototypes that provide significant new capabilities, such as a computer system that automates some of the functions of Apollo s CapCom. Thus, analog studies have created a community of practice-a new collaboration between scientists and engineers-so that technology begins with real human needs and works incrementally towards the challenges of the human exploration of Mars.

Tissue engineering.

PubMed

Katari, Ravi S; Peloso, Andrea; Orlando, Giuseppe

2014-01-01

Ultimately much work remains to be done in the companion fields of biomaterials and stem cells. Nonetheless, the monumental progress in TE that has been reported in the studies summarized here demonstrates that regenerative approaches to problems in general surgery need to be explored in more depth. Furthermore, the surgical disciplines of reconstruction and transplantation need to recognize their research counterparts in TE, given its potential to actualize freedom from immunosuppression, one of the most elusive goals in modern surgery. The engineering and proliferation of autologous cells, tissues, and organs ex vivo before surgical operation can significantly reduce the obstacles current practitioners are intimately familiar with: donor site morbidity and immunologic rejection. Therefore, in addition to the truly exciting research and development prospects and implications for the commercial sector, patients with end-stage diseases and debilitating injury stand to gain the most from clinically adapted TE therapies.

Database on Demand: insight how to build your own DBaaS

NASA Astrophysics Data System (ADS)

Gaspar Aparicio, Ruben; Coterillo Coz, Ignacio

2015-12-01

At CERN, a number of key database applications are running on user-managed MySQL, PostgreSQL and Oracle database services. The Database on Demand (DBoD) project was born out of an idea to provide CERN user community with an environment to develop and run database services as a complement to the central Oracle based database service. The Database on Demand empowers the user to perform certain actions that had been traditionally done by database administrators, providing an enterprise platform for database applications. It also allows the CERN user community to run different database engines, e.g. presently three major RDBMS (relational database management system) vendors are offered. In this article we show the actual status of the service after almost three years of operations, some insight of our new redesign software engineering and near future evolution.

Evolutionary mechanics: new engineering principles for the emergence of flexibility in a dynamic and uncertain world.

PubMed

Whitacre, James M; Rohlfshagen, Philipp; Bender, Axel; Yao, Xin

2012-09-01

Engineered systems are designed to deftly operate under predetermined conditions yet are notoriously fragile when unexpected perturbations arise. In contrast, biological systems operate in a highly flexible manner; learn quickly adequate responses to novel conditions, and evolve new routines and traits to remain competitive under persistent environmental change. A recent theory on the origins of biological flexibility has proposed that degeneracy-the existence of multi-functional components with partially overlapping functions-is a primary determinant of the robustness and adaptability found in evolved systems. While degeneracy's contribution to biological flexibility is well documented, there has been little investigation of degeneracy design principles for achieving flexibility in systems engineering. Actually, the conditions that can lead to degeneracy are routinely eliminated in engineering design. With the planning of transportation vehicle fleets taken as a case study, this article reports evidence that degeneracy improves the robustness and adaptability of a simulated fleet towards unpredicted changes in task requirements without incurring costs to fleet efficiency. We find that degeneracy supports faster rates of design adaptation and ultimately leads to better fleet designs. In investigating the limitations of degeneracy as a design principle, we consider decision-making difficulties that arise from degeneracy's influence on fleet complexity. While global decision-making becomes more challenging, we also find degeneracy accommodates rapid distributed decision-making leading to (near-optimal) robust system performance. Given the range of conditions where favorable short-term and long-term performance outcomes are observed, we propose that degeneracy may fundamentally alter the propensity for adaptation and is useful within different engineering and planning contexts.

Electric Utility Transmission and Distribution Line Engineering Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peter McKenny

2010-08-31

Economic development in the United States depends on a reliable and affordable power supply. The nation will need well educated engineers to design a modern, safe, secure, and reliable power grid for our future needs. An anticipated shortage of qualified engineers has caused considerable concern in many professional circles, and various steps are being taken nationwide to alleviate the potential shortage and ensure the North American power system's reliability, and our world-wide economic competitiveness. To help provide a well-educated and trained workforce which can sustain and modernize the nation's power grid, Gonzaga University's School of Engineering and Applied Science hasmore » established a five-course (15-credit hour) Certificate Program in Transmission and Distribution (T&D) Engineering. The program has been specifically designed to provide working utility engineering professionals with on-line access to advanced engineering courses which cover modern design practice with an industry-focused theoretical foundation. A total of twelve courses have been developed to-date and students may select any five in their area of interest for the T&D Certificate. As each course is developed and taught by a team of experienced engineers (from public and private utilities, consultants, and industry suppliers), students are provided a unique opportunity to interact directly with different industry experts over the eight weeks of each course. Course material incorporates advanced aspects of civil, electrical, and mechanical engineering disciplines that apply to power system design and are appropriate for graduate engineers. As such, target students for the certificate program include: (1) recent graduates with a Bachelor of Science Degree in an engineering field (civil, mechanical, electrical, etc.); (2) senior engineers moving from other fields to the utility industry (i.e. paper industry to utility engineering or project management positions); and (3) regular working professionals wishing to update their skills or increase their knowledge of utility engineering design practices and procedures. By providing graduate educational opportunities for the above groups, the T&D Program will help serve a strong industry need for training the next generation of engineers in the cost-effective design, construction, operation, and maintenance of modern electrical transmission and distribution systems. In addition to developing the on-line engineering courses described above, the T&D Program also focused significant efforts towards enhancing the training opportunities available to power system operators in the northwest. These efforts have included working with outside vendors to provide NERC-approved training courses in Gonzaga University's (GU) system operator training facility, support for an accurate system model which can be used in regional blackstart exercises, and the identification of a retired system operator who could provide actual regional training courses. The GU system operator training facility is also being used to recruit young workers, veterans, and various under-represented groups to the utility industry. Over the past three years students from Columbia Gorge Community College, Spokane Falls Community College, Walla Walla Community College, Central Washington University, Eastern Washington University, Gonzaga University, and various local high schools have attended short (one-day) system operator training courses free of charge. These collaboration efforts has been extremely well received by both students and industry, and meet T&D Program objectives of strengthening the power industry workforce while bridging the knowledge base across power worker categories, and recruiting new workers to replace a predominantly retirement age workforce. In the past three years the T&D Program has provided over 170 utility engineers with access to advanced engineering courses, been involved in training more than 300 power system operators, and provided well over 500 college and high school students with an experience in running a power system simulator and an exposure to various utility-related professions and craft trades.« less

Reinforcement-learning-based dual-control methodology for complex nonlinear discrete-time systems with application to spark engine EGR operation.

PubMed

Shih, Peter; Kaul, Brian C; Jagannathan, S; Drallmeier, James A

2008-08-01

A novel reinforcement-learning-based dual-control methodology adaptive neural network (NN) controller is developed to deliver a desired tracking performance for a class of complex feedback nonlinear discrete-time systems, which consists of a second-order nonlinear discrete-time system in nonstrict feedback form and an affine nonlinear discrete-time system, in the presence of bounded and unknown disturbances. For example, the exhaust gas recirculation (EGR) operation of a spark ignition (SI) engine is modeled by using such a complex nonlinear discrete-time system. A dual-controller approach is undertaken where primary adaptive critic NN controller is designed for the nonstrict feedback nonlinear discrete-time system whereas the secondary one for the affine nonlinear discrete-time system but the controllers together offer the desired performance. The primary adaptive critic NN controller includes an NN observer for estimating the states and output, an NN critic, and two action NNs for generating virtual control and actual control inputs for the nonstrict feedback nonlinear discrete-time system, whereas an additional critic NN and an action NN are included for the affine nonlinear discrete-time system by assuming the state availability. All NN weights adapt online towards minimization of a certain performance index, utilizing gradient-descent-based rule. Using Lyapunov theory, the uniformly ultimate boundedness (UUB) of the closed-loop tracking error, weight estimates, and observer estimates are shown. The adaptive critic NN controller performance is evaluated on an SI engine operating with high EGR levels where the controller objective is to reduce cyclic dispersion in heat release while minimizing fuel intake. Simulation and experimental results indicate that engine out emissions drop significantly at 20% EGR due to reduction in dispersion in heat release thus verifying the dual-control approach.

Robustness

NASA Astrophysics Data System (ADS)

Ryan, R.

1993-03-01

Robustness is a buzz word common to all newly proposed space systems design as well as many new commercial products. The image that one conjures up when the word appears is a 'Paul Bunyon' (lumberjack design), strong and hearty; healthy with margins in all aspects of the design. In actuality, robustness is much broader in scope than margins, including such factors as simplicity, redundancy, desensitization to parameter variations, control of parameter variations (environments flucation), and operational approaches. These must be traded with concepts, materials, and fabrication approaches against the criteria of performance, cost, and reliability. This includes manufacturing, assembly, processing, checkout, and operations. The design engineer or project chief is faced with finding ways and means to inculcate robustness into an operational design. First, however, be sure he understands the definition and goals of robustness. This paper will deal with these issues as well as the need for the requirement for robustness.

Robustness

NASA Technical Reports Server (NTRS)

Ryan, R.

1993-01-01

Robustness is a buzz word common to all newly proposed space systems design as well as many new commercial products. The image that one conjures up when the word appears is a 'Paul Bunyon' (lumberjack design), strong and hearty; healthy with margins in all aspects of the design. In actuality, robustness is much broader in scope than margins, including such factors as simplicity, redundancy, desensitization to parameter variations, control of parameter variations (environments flucation), and operational approaches. These must be traded with concepts, materials, and fabrication approaches against the criteria of performance, cost, and reliability. This includes manufacturing, assembly, processing, checkout, and operations. The design engineer or project chief is faced with finding ways and means to inculcate robustness into an operational design. First, however, be sure he understands the definition and goals of robustness. This paper will deal with these issues as well as the need for the requirement for robustness.

Space network scheduling benchmark: A proof-of-concept process for technology transfer

NASA Technical Reports Server (NTRS)

Moe, Karen; Happell, Nadine; Hayden, B. J.; Barclay, Cathy

1993-01-01

This paper describes a detailed proof-of-concept activity to evaluate flexible scheduling technology as implemented in the Request Oriented Scheduling Engine (ROSE) and applied to Space Network (SN) scheduling. The criteria developed for an operational evaluation of a reusable scheduling system is addressed including a methodology to prove that the proposed system performs at least as well as the current system in function and performance. The improvement of the new technology must be demonstrated and evaluated against the cost of making changes. Finally, there is a need to show significant improvement in SN operational procedures. Successful completion of a proof-of-concept would eventually lead to an operational concept and implementation transition plan, which is outside the scope of this paper. However, a high-fidelity benchmark using actual SN scheduling requests has been designed to test the ROSE scheduling tool. The benchmark evaluation methodology, scheduling data, and preliminary results are described.

A facility monitoring system: The single most valuable and cost-effective tool available to an energy manager

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holmes, W.A.

Energy engineering and management combines engineering problem-solving and financial management techniques to reduce utility costs. At present, substantial amounts of time and money are being spent in order to attempt to quantify energy consumption and costs and define opportunities for savings. Unfortunately, accurate verification of results is often overlooked. Advances in technology during the last few years have made the installation of a permanent, PC-based monitoring system possible for any facility, often for no more than the cost of a detailed study. By investing initially in a monitoring system rather than audits or studies, the actual consumption and cost datamore » will be available on a continuing basis and can be used to produce immediate operational savings, more accurately analyze opportunities requiring capital investments, and to verify actual savings resulting from changes. A permanent monitoring system, installed as the first step in a utility cost reduction effort, to identify where and how energy is used in a facility on a dynamic and real-time basis, can provide the most valuable and cost-effective tool available to an energy manager. The resulting data allows energy consumption patterns and utility costs to be understood and managed in the same manner as all other costs within a facility.« less

Incorporation of quality updates for JPSS CGS Products

NASA Astrophysics Data System (ADS)

Cochran, S.; Grant, K. D.; Ibrahim, W.; Brueske, K. F.; Smit, P.

2016-12-01

NOAA's next-generation environmental satellite, the Joint Polar Satellite System (JPSS) replaces the current Polar-orbiting Operational Environmental Satellites (POES). JPSS satellites carry sensors which collect meteorological, oceanographic, climatological, and solar-geophysical observations of the earth, atmosphere, and space. The first JPSS satellite was launched in 2011 and is currently NOAA's primary operational polar satellite. The JPSS ground system is the Common Ground System (CGS), and provides command, control, and communications (C3) and data processing (DP). A multi-mission system, CGS provides combinations of C3/DP for numerous NASA, NOAA, DoD, and international missions. In preparation for the next JPSS satellite, CGS improved its multi-mission capabilities to enhance mission operations for larger constellations of earth observing satellites with the added benefit of streamlining mission operations for other NOAA missions. This paper will discuss both the theoretical basis and the actual practices used to date to identify, test and incorporate algorithm updates into the CGS processing baseline. To provide a basis for this support, Raytheon developed a theoretical analysis framework, and the application of derived engineering processes, for the maintenance of consistency and integrity of remote sensing operational algorithm outputs. The framework is an abstraction of the operationalization of the science-grade algorithm (Sci2Ops) process used throughout the JPSS program. By combining software and systems engineering controls, manufacturing disciplines to detect and reduce defects, and a standard process to control analysis, an environment to maintain operational algorithm maturity is achieved. Results of the use of this approach to implement algorithm changes into operations will also be detailed.

Methods and Tools for Product Quality Maintenance in JPSS CGS

NASA Astrophysics Data System (ADS)

Cochran, S.; Smit, P.; Grant, K. D.; Jamilkowski, M. L.

2015-12-01

NOAA's next-generation environmental satellite, the Joint Polar Satellite System (JPSS) replaces the current Polar-orbiting Operational Environmental Satellites (POES). JPSS satellites carry sensors which collect meteorological, oceanographic, climatological, and solar-geophysical observations of the earth, atmosphere, and space. The first JPSS satellite was launched in 2011 and is currently NOAA's primary operational polar satellite. The JPSS ground system is the Common Ground System (CGS), and provides command, control, and communications (C3) and data processing (DP). A multi-mission system, CGS provides combinations of C3/DP for numerous NASA, NOAA, DoD, and international missions. In preparation for the next JPSS satellite, CGS improved its multi-mission capabilities to enhance mission operations for larger constellations of earth observing satellites with the added benefit of streamlining mission operations for other NOAA missions. This paper will discuss both the theoretical basis and the actual practices used to date to identify, test and incorporate algorithm updates into the CGS processing baseline. To provide a basis for this support, Raytheon developed a theoretical analysis framework, and the application of derived engineering processes, for the maintenance of consistency and integrity of remote sensing operational algorithm outputs. The framework is an abstraction of the operationalization of the science-grade algorithm (Sci2Ops) process used throughout the JPSS program. By combining software and systems engineering controls, manufacturing disciplines to detect and reduce defects, and a standard process to control analysis, an environment to maintain operational algorithm maturity is achieved. Results of the use of this approach to implement algorithm changes into operations will also be detailed.

Advanced automation in space shuttle mission control

NASA Technical Reports Server (NTRS)

Heindel, Troy A.; Rasmussen, Arthur N.; Mcfarland, Robert Z.

1991-01-01

The Real Time Data System (RTDS) Project was undertaken in 1987 to introduce new concepts and technologies for advanced automation into the Mission Control Center environment at NASA's Johnson Space Center. The project's emphasis is on producing advanced near-operational prototype systems that are developed using a rapid, interactive method and are used by flight controllers during actual Shuttle missions. In most cases the prototype applications have been of such quality and utility that they have been converted to production status. A key ingredient has been an integrated team of software engineers and flight controllers working together to quickly evolve the demonstration systems.

Test Rig for Evaluating Active Turbine Blade Tip Clearance Control Concepts

NASA Technical Reports Server (NTRS)

Lattime, Scott B.; Steinetz, Bruce M.; Robbie, Malcolm G.

2003-01-01

Improved blade tip sealing in the high pressure compressor and high pressure turbine can provide dramatic improvements in specific fuel consumption, time-on-wing, compressor stall margin and engine efficiency as well as increased payload and mission range capabilities of both military and commercial gas turbine engines. The preliminary design of a mechanically actuated active clearance control (ACC) system for turbine blade tip clearance management is presented along with the design of a bench top test rig in which the system is to be evaluated. The ACC system utilizes mechanically actuated seal carrier segments and clearance measurement feedback to provide fast and precise active clearance control throughout engine operation. The purpose of this active clearance control system is to improve upon current case cooling methods. These systems have relatively slow response and do not use clearance measurement, thereby forcing cold build clearances to set the minimum clearances at extreme operating conditions (e.g., takeoff, re-burst) and not allowing cruise clearances to be minimized due to the possibility of throttle transients (e.g., step change in altitude). The active turbine blade tip clearance control system design presented herein will be evaluated to ensure that proper response and positional accuracy is achievable under simulated high-pressure turbine conditions. The test rig will simulate proper seal carrier pressure and temperature loading as well as the magnitudes and rates of blade tip clearance changes of an actual gas turbine engine. The results of these evaluations will be presented in future works.

Program test objectives milestone 3. [Integrated Propulsion Technology Demonstrator

NASA Technical Reports Server (NTRS)

Gaynor, T. L.

1994-01-01

The following conclusions have been developed relative to propulsion system technology adequacy for efficient development and operation of recoverable and expendable launch vehicles (RLV and ELV) and the benefits which the integrated propulsion technology demonstrator will provide for enhancing technology: (1) Technology improvements relative to propulsion system design and operation can reduce program cost. Many features or improvement needs to enhance operability, reduce cost, and improve payload are identified. (2) The Integrated Propulsion Technology Demonstrator (IPTD) Program provides a means of resolving the majority of issues associated with improvement needs. (3) The IPTD will evaluate complex integration of vehicle and facility functions in fluid management and propulsion control systems, and provides an environment for validating improved mechanical and electrical components. (4) The IPTD provides a mechanism for investigating operational issues focusing on reducing manpower and time to perform various functions at the launch site. These efforts include model development, collection of data to validate subject models, and ultimate development of complex time line models. (5) The IPTD provides an engine test bed for tri/bi-propellant engine development firings which is representative of the actual vehicle environment. (6) The IPTD provides for only a limited multiengine configuration integration environment for RLV. Multiengine efforts may be simulated for a number of subsystems and a number of subsystems are relatively independent of the multiengine influences.

Detecting the crankshaft torsional vibration of diesel engines for combustion related diagnosis

NASA Astrophysics Data System (ADS)

Charles, P.; Sinha, Jyoti K.; Gu, F.; Lidstone, L.; Ball, A. D.

2009-04-01

Early fault detection and diagnosis for medium-speed diesel engines is important to ensure reliable operation throughout the course of their service. This work presents an investigation of the diesel engine combustion related fault detection capability of crankshaft torsional vibration. The encoder signal, often used for shaft speed measurement, has been used to construct the instantaneous angular speed (IAS) waveform, which actually represents the signature of the torsional vibration. Earlier studies have shown that the IAS signal and its fast Fourier transform (FFT) analysis are effective for monitoring engines with less than eight cylinders. The applicability to medium-speed engines, however, is strongly contested due to the high number of cylinders and large moment of inertia. Therefore the effectiveness of the FFT-based approach has further been enhanced by improving the signal processing to determine the IAS signal and subsequently tested on a 16-cylinder engine. In addition, a novel method of presentation, based on the polar coordinate system of the IAS signal, has also been introduced; to improve the discrimination features of the faults compared to the FFT-based approach of the IAS signal. The paper discusses two typical experimental studies on 16- and 20-cylinder engines, with and without faults, and the diagnosis results by the proposed polar presentation method. The results were also compared with the earlier FFT-based method of the IAS signal.

The Virtual Test Bed Project

NASA Technical Reports Server (NTRS)

Rabelo, Luis C.

2002-01-01

This is a report of my activities as a NASA Fellow during the summer of 2002 at the NASA Kennedy Space Center (KSC). The core of these activities is the assigned project: the Virtual Test Bed (VTB) from the Spaceport Engineering and Technology Directorate. The VTB Project has its foundations in the NASA Ames Research Center (ARC) Intelligent Launch & Range Operations program. The objective of the VTB project is to develop a new and unique collaborative computing environment where simulation models can be hosted and integrated in a seamless fashion. This collaborative computing environment will be used to build a Virtual Range as well as a Virtual Spaceport. This project will work as a technology pipeline to research, develop, test and validate R&D efforts against real time operations without interfering with the actual operations or consuming the operational personnel s time. This report will also focus on the systems issues required to conceptualize and provide form to a systems architecture capable of handling the different demands.

Method and system for fault accommodation of machines

NASA Technical Reports Server (NTRS)

Goebel, Kai Frank (Inventor); Subbu, Rajesh Venkat (Inventor); Rausch, Randal Thomas (Inventor); Frederick, Dean Kimball (Inventor)

2011-01-01

A method for multi-objective fault accommodation using predictive modeling is disclosed. The method includes using a simulated machine that simulates a faulted actual machine, and using a simulated controller that simulates an actual controller. A multi-objective optimization process is performed, based on specified control settings for the simulated controller and specified operational scenarios for the simulated machine controlled by the simulated controller, to generate a Pareto frontier-based solution space relating performance of the simulated machine to settings of the simulated controller, including adjustment to the operational scenarios to represent a fault condition of the simulated machine. Control settings of the actual controller are adjusted, represented by the simulated controller, for controlling the actual machine, represented by the simulated machine, in response to a fault condition of the actual machine, based on the Pareto frontier-based solution space, to maximize desirable operational conditions and minimize undesirable operational conditions while operating the actual machine in a region of the solution space defined by the Pareto frontier.

Model based design of electronic throttle control

NASA Astrophysics Data System (ADS)

Cherian, Fenin; Ranjan, Ashish; Bhowmick, Pathikrit; Rammohan, A.

2017-11-01

With the advent of torque based Engine Management Systems, the precise control and robust performance of the throttle body becomes a key factor in the overall performance of the vehicle. Electronic Throttle Control provides benefits such as improved air-fuel ratio for improving the vehicle performance and lower exhausts emissions to meet the stringent emission norms. Modern vehicles facilitate various features such as Cruise Control, Traction Control, Electronic Stability Program and Pre-crash systems. These systems require control over engine power without driver intervention, which is not possible with conventional mechanical throttle system. Thus these systems are integrated to function with the electronic throttle control. However, due to inherent non-linearities in the throttle body, the control becomes a difficult task. In order to eliminate the influence of this hysteresis at the initial operation of the butterfly valve, a control to compensate the shortage must be added to the duty required for starting throttle operation when the initial operation is detected. Therefore, a lot of work is being done in this field to incorporate the various nonlinearities to achieve robust control. In our present work, the ETB was tested to verify the working of the system. Calibration of the TPS sensors was carried out in order to acquire accurate throttle opening angle. The response of the calibrated system was then plotted against a step input signal. A linear model of the ETB was prepared using Simulink and its response was compared with the experimental data to find out the initial deviation of the model from the actual system. To reduce this deviation, non-linearities from existing literature were introduced to the system and a response analysis was performed to check the deviation from the actual system. Based on this investigation, an introduction of a new nonlinearity parameter can be used in future to reduce the deviation further making the control of the ETB more precise and accurate.

Strategies for Limiting Engineers' Potential Liability for Indoor Air Quality Problems.

PubMed

von Oppenfeld, Rolf R; Freeze, Mark E; Sabo, Sean M

1998-10-01

Engineers face indoor air quality (IAQ) issues at the design phase of building construction as well as during the investigation and mitigation of potential indoor air pollution problems during building operation. IAQ issues that can be identified are "building-related illnesses" that may include problems of volatile organic compounds (VOCs). IAQ issues that cannot be identified are termed "sick building syndrome." Frequently, microorganism-caused illnesses are difficult to confirm. Engineers who provide professional services that directly or indirectly impact IAQ face significant potential liability to clients and third parties when performing these duties. Potential theories supporting liability claims for IAQ problems against engineers include breach of contract and various common law tort theories such as negligence and negligent misrepresentation. Furthermore, an increasing number of federal, state, and local regulations affect IAQ issues and can directly increase the potential liability of engineers. A duty to disclose potential or actual air quality concerns to third parties may apply for engineers in given circumstances. Such a duty may arise from judicial precedent, the Model Guide for Professional Conduct for Engineers, or the Code of Ethics for Engineers. Practical strategies engineers can use to protect themselves from liability include regular training and continuing education in relevant regulatory, scientific, and case law developments; detailed documentation and recordkeeping practices; adequate insurance coverage; contractual indemnity clauses; contractual provisions limiting liability to the scope of work performed; and contractual provisions limiting the extent of liability for engineers' negligence. Furthermore, through the proper use of building materials and construction techniques, an engineer or other design professional can effectively limit the potential for IAQ liability.

Modeling of Commercial Turbofan Engine With Ice Crystal Ingestion: Follow-On

NASA Technical Reports Server (NTRS)

Jorgenson, Philip C. E.; Veres, Joseph P.; Coennen, Ryan

2014-01-01

The occurrence of ice accretion within commercial high bypass aircraft turbine engines has been reported under certain atmospheric conditions. Engine anomalies have taken place at high altitudes that have been attributed to ice crystal ingestion, partially melting, and ice accretion on the compression system components. The result was degraded engine performance, and one or more of the following: loss of thrust control (roll back), compressor surge or stall, and flameout of the combustor. As ice crystals are ingested into the fan and low pressure compression system, the increase in air temperature causes a portion of the ice crystals to melt. It is hypothesized that this allows the ice-water mixture to cover the metal surfaces of the compressor stationary components which leads to ice accretion through evaporative cooling. Ice accretion causes a blockage which subsequently results in the deterioration in performance of the compressor and engine. The focus of this research is to apply an engine icing computational tool to simulate the flow through a turbofan engine and assess the risk of ice accretion. The tool is comprised of an engine system thermodynamic cycle code, a compressor flow analysis code, and an ice particle melt code that has the capability of determining the rate of sublimation, melting, and evaporation through the compressor flow path, without modeling the actual ice accretion. A commercial turbofan engine which has previously experienced icing events during operation in a high altitude ice crystal environment has been tested in the Propulsion Systems Laboratory (PSL) altitude test facility at NASA Glenn Research Center. The PSL has the capability to produce a continuous ice cloud which is ingested by the engine during operation over a range of altitude conditions. The PSL test results confirmed that there was ice accretion in the engine due to ice crystal ingestion, at the same simulated altitude operating conditions as experienced previously in flight. The computational tool was utilized to help guide a portion of the PSL testing, and was used to predict ice accretion could also occur at significantly lower altitudes. The predictions were qualitatively verified by subsequent testing of the engine in the PSL. In a previous study, analysis of select PSL test data points helped to calibrate the engine icing computational tool to assess the risk of ice accretion. This current study is a continuation of that data analysis effort. The study focused on tracking the variations in wet bulb temperature and ice particle melt ratio through the engine core flow path. The results from this study have identified trends, while also identifying gaps in understanding as to how the local wet bulb temperature and melt ratio affects the risk of ice accretion and subsequent engine behavior.

Modeling of Commercial Turbofan Engine with Ice Crystal Ingestion; Follow-On

NASA Technical Reports Server (NTRS)

Jorgenson, Philip C. E.; Veres, Joseph P.; Coennen, Ryan

2014-01-01

The occurrence of ice accretion within commercial high bypass aircraft turbine engines has been reported under certain atmospheric conditions. Engine anomalies have taken place at high altitudes that have been attributed to ice crystal ingestion, partially melting, and ice accretion on the compression system components. The result was degraded engine performance, and one or more of the following: loss of thrust control (roll back), compressor surge or stall, and flameout of the combustor. As ice crystals are ingested into the fan and low pressure compression system, the increase in air temperature causes a portion of the ice crystals to melt. It is hypothesized that this allows the ice-water mixture to cover the metal surfaces of the compressor stationary components which leads to ice accretion through evaporative cooling. Ice accretion causes a blockage which subsequently results in the deterioration in performance of the compressor and engine. The focus of this research is to apply an engine icing computational tool to simulate the flow through a turbofan engine and assess the risk of ice accretion. The tool is comprised of an engine system thermodynamic cycle code, a compressor flow analysis code, and an ice particle melt code that has the capability of determining the rate of sublimation, melting, and evaporation through the compressor flow path, without modeling the actual ice accretion. A commercial turbofan engine which has previously experienced icing events during operation in a high altitude ice crystal environment has been tested in the Propulsion Systems Laboratory (PSL) altitude test facility at NASA Glenn Research Center. The PSL has the capability to produce a continuous ice cloud which is ingested by the engine during operation over a range of altitude conditions. The PSL test results confirmed that there was ice accretion in the engine due to ice crystal ingestion, at the same simulated altitude operating conditions as experienced previously in flight. The computational tool was utilized to help guide a portion of the PSL testing, and was used to predict ice accretion could also occur at significantly lower altitudes. The predictions were qualitatively verified by subsequent testing of the engine in the PSL. In a previous study, analysis of select PSL test data points helped to calibrate the engine icing computational tool to assess the risk of ice accretion. This current study is a continuation of that data analysis effort. The study focused on tracking the variations in wet bulb temperature and ice particle melt ratio through the engine core flow path. The results from this study have identified trends, while also identifying gaps in understanding as to how the local wet bulb temperature and melt ratio affects the risk of ice accretion and subsequent engine behavior.

An RL10A-3-3A rocket engine model using the rocket engine transient simulator (ROCETS) software

NASA Technical Reports Server (NTRS)

Binder, Michael

1993-01-01

Steady-state and transient computer models of the RL10A-3-3A rocket engine have been created using the Rocket Engine Transient Simulation (ROCETS) code. These models were created for several purposes. The RL10 engine is a critical component of past, present, and future space missions; the model will give NASA an in-house capability to simulate the performance of the engine under various operating conditions and mission profiles. The RL10 simulation activity is also an opportunity to further validate the ROCETS program. The ROCETS code is an important tool for modeling rocket engine systems at NASA Lewis. ROCETS provides a modular and general framework for simulating the steady-state and transient behavior of any desired propulsion system. Although the ROCETS code is being used in a number of different analysis and design projects within NASA, it has not been extensively validated for any system using actual test data. The RL10A-3-3A has a ten year history of test and flight applications; it should provide sufficient data to validate the ROCETS program capability. The ROCETS models of the RL10 system were created using design information provided by Pratt & Whitney, the engine manufacturer. These models are in the process of being validated using test-stand and flight data. This paper includes a brief description of the models and comparison of preliminary simulation output against flight and test-stand data.

Efficiencies and coefficients of performance of heat engines, refrigerators, and heat pumps with friction: a universal limiting behavior.

PubMed

Bizarro, João P S; Rodrigues, Paulo

2012-11-01

For work-producing heat engines, or work-consuming refrigerators and heat pumps, the percentage decrease caused by friction in their efficiencies, or coefficients of performance (COP's), is approximately given by the ratio W(fric)/W between the work spent against friction forces and the work performed by, or delivered to, the working fluid. This universal scaling, which applies in the limit of small friction (W(fric)/W

Analyzing system safety in lithium-ion grid energy storage

DOE PAGES

Rosewater, David; Williams, Adam

2015-10-08

As grid energy storage systems become more complex, it grows more di cult to design them for safe operation. This paper first reviews the properties of lithium-ion batteries that can produce hazards in grid scale systems. Then the conventional safety engineering technique Probabilistic Risk Assessment (PRA) is reviewed to identify its limitations in complex systems. To address this gap, new research is presented on the application of Systems-Theoretic Process Analysis (STPA) to a lithium-ion battery based grid energy storage system. STPA is anticipated to ll the gaps recognized in PRA for designing complex systems and hence be more e ectivemore » or less costly to use during safety engineering. It was observed that STPA is able to capture causal scenarios for accidents not identified using PRA. Additionally, STPA enabled a more rational assessment of uncertainty (all that is not known) thereby promoting a healthy skepticism of design assumptions. Lastly, we conclude that STPA may indeed be more cost effective than PRA for safety engineering in lithium-ion battery systems. However, further research is needed to determine if this approach actually reduces safety engineering costs in development, or improves industry safety standards.« less

Structural Life and Reliability Metrics: Benchmarking and Verification of Probabilistic Life Prediction Codes

NASA Technical Reports Server (NTRS)

Litt, Jonathan S.; Soditus, Sherry; Hendricks, Robert C.; Zaretsky, Erwin V.

2002-01-01

Over the past two decades there has been considerable effort by NASA Glenn and others to develop probabilistic codes to predict with reasonable engineering certainty the life and reliability of critical components in rotating machinery and, more specifically, in the rotating sections of airbreathing and rocket engines. These codes have, to a very limited extent, been verified with relatively small bench rig type specimens under uniaxial loading. Because of the small and very narrow database the acceptance of these codes within the aerospace community has been limited. An alternate approach to generating statistically significant data under complex loading and environments simulating aircraft and rocket engine conditions is to obtain, catalog and statistically analyze actual field data. End users of the engines, such as commercial airlines and the military, record and store operational and maintenance information. This presentation describes a cooperative program between the NASA GRC, United Airlines, USAF Wright Laboratory, U.S. Army Research Laboratory and Australian Aeronautical & Maritime Research Laboratory to obtain and analyze these airline data for selected components such as blades, disks and combustors. These airline data will be used to benchmark and compare existing life prediction codes.

Cryogenic Thermal Performance Testing of Bulk-Fill and Aerogel Insulation Materials

NASA Technical Reports Server (NTRS)

Scholtens, B. E.; Fesmire, J. E.; Sass, J. P.; Augustynowicz, S. D.; Heckle, K. W.

2007-01-01

The research testing and demonstration of new bulk-fill materials for cryogenic thermal insulation systems was performed by the Cryogenics Test Laboratory at NASA Kennedy Space Center. Thermal conductivity testing under actual-use cryogenic conditions is a key to understanding the total system performance encompassing engineering, economics, and materials factors. A number of bulk fill insulation materials, including aerogel beads, glass bubbles, and perlite powder, were tested using a new cylindrical cryostat. Boundary temperatures for the liquid nitrogen boil-off method were 293 K and 78 K. Tests were performed as a function of cold vacuum pressure from high vacuum to no vacuum conditions. Results are compared with other complementary test methods in the range of 300 K to 20 K. Various testing techniques are shown to be required to obtain a complete understanding of the operating performance of a material and to provide data for answers to design engineering questions.

Fuel conservation evaluation of US (United States) Army helicopters. Part 4. OH-58C flight testing. Final report 22 Sep 20-Nov 82

DOE Office of Scientific and Technical Information (OSTI.GOV)

Belte, D.; Stratton, M.V.

1982-08-01

The United States Army Aviation Engineering Flight Activity conducted level flight performance tests of the OH-58C helicopter at Edwards AFB, California from 22 September to 20 November 1981, and at St. Paul, Minnesota, from 12 January to 9 February 1982. Nondimensional methods were used to identify effects of compressibility and blade stall on performance, and increased referred rotor speeds were used to supplement the range of currently available level flight data. Maximum differences in nondimensional power required attributed to compressibility effects varied from 6.5 to 11%. However, high actual rotor speed at a given condition can result in less powermore » required than at low rotor speed even with the compressibility penalty. The power required characteristics determined by these tests can be combined with engine performance to determine the most fuel efficient operating conditions.« less

Development of advanced high-temperature heat flux sensors. Phase 2: Verification testing

NASA Technical Reports Server (NTRS)

Atkinson, W. H.; Cyr, M. A.; Strange, R. R.

1985-01-01

A two-phase program is conducted to develop heat flux sensors capable of making heat flux measurements throughout the hot section of gas turbine engines. In Phase 1, three types of heat flux sensors are selected; embedded thermocouple, laminated, and Gardon gauge sensors. A demonstration of the ability of these sensors to operate in an actual engine environment is reported. A segmented liner of each of two combustors being used in the Broad Specification Fuels Combustor program is instrumented with the three types of heat flux sensors then tested in a high pressure combustor rig. Radiometer probes are also used to measure the radiant heat loads to more fully characterize the combustor environment. Test results show the heat flux sensors to be in good agreement with radiometer probes and the predicted data trends. In general, heat flux sensors have strong potential for use in combustor development programs.

Air/fuel ratio control system for internal combustion engine having rotary valve and step motor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saito, M.

A system for feedback control of the air/fuel mixing ratio in an internal combustion engine equipped with a carburetor. The control system has an air/fuel ratio detector of a gas sensor type which provides a feedback signal to a control circuit and a rotary valve which is operated by a stepping motor responsive to a control pulse signal produced by the control circuit to regulate the fuel feed rate so as to nullify a deviation of the detected actual air/fuel ratio from a preset air/fuel ratio. The control system may include two auxiliary air-admitting passages respectively connected to a mainmore » fuel passage and a slow fuel passage in the carburetor, and in this case the single rotary valve is designed and arranged so as to simultaneously control the admission of air into both of the two auxiliary air-admitting passages.« less

Resonant tunneling diode based on band gap engineered graphene antidot structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Palla, Penchalaiah, E-mail: penchalaiah.palla@vit.ac.in; Ethiraj, Anita S.; Raina, J. P.

The present work demonstrates the operation and performance of double barrier Graphene Antidot Resonant Tunnel Diode (DBGA-RTD). Non-Equilibrium Green’s Function (NEGF) frame work with tight-binding Hamiltonian and 2-D Poisson equations were solved self-consistently for device study. The interesting feature in this device is that it is an all graphene RTD with band gap engineered graphene antidot tunnel barriers. Another interesting new finding is that it shows negative differential resistance (NDR), which involves the resonant tunneling in the graphene quantum well through both the electron and hole bound states. The Graphene Antidot Lattice (GAL) barriers in this device efficiently improved themore » Peak to Valley Ratio to approximately 20 even at room temperature. A new fitting model is developed for the number of antidots and their corresponding effective barrier width, which will help in determining effective barrier width of any size of actual antidot geometry.« less

Where Is the Engineering I Applied For? A Longitudinal Study of Students' Transition into Higher Education Engineering, and Their Considerations of Staying or Leaving

ERIC Educational Resources Information Center

Holmegaard, Henriette Tolstrup; Madsen, Lene Møller; Ulriksen, Lars

2016-01-01

This paper presents results from a qualitative longitudinal study of students' transition into higher education engineering. The study aims at comparing upper-secondary school students' expectations of engineering with their actual experiences when encountering the engineering programme. It explores how this encounter provides a platform for…

A Collaborative Analysis Tool for Integrating Hypersonic Aerodynamics, Thermal Protection Systems, and RBCC Engine Performance for Single Stage to Orbit Vehicles

NASA Technical Reports Server (NTRS)

Stanley, Thomas Troy; Alexander, Reginald

1999-01-01

Presented is a computer-based tool that connects several disciplines that are needed in the complex and integrated design of high performance reusable single stage to orbit (SSTO) vehicles. Every system is linked to every other system, as is the case of SSTO vehicles with air breathing propulsion, which is currently being studied by NASA. The deficiencies in the scramjet powered concept led to a revival of interest in Rocket-Based Combined-Cycle (RBCC) propulsion systems. An RBCC propulsion system integrates airbreathing and rocket propulsion into a single engine assembly enclosed within a cowl or duct. A typical RBCC propulsion system operates as a ducted rocket up to approximately Mach 3. At this point the transitions to a ramjet mode for supersonic-to-hypersonic acceleration. Around Mach 8 the engine transitions to a scram4jet mode. During the ramjet and scramjet modes, the integral rockets operate as fuel injectors. Around Mach 10-12 (the actual value depends on vehicle and mission requirements), the inlet is physically closed and the engine transitions to an integral rocket mode for orbit insertion. A common feature of RBCC propelled vehicles is the high degree of integration between the propulsion system and airframe. At high speeds the vehicle forebody is fundamentally part of the engine inlet, providing a compression surface for air flowing into the engine. The compressed air is mixed with fuel and burned. The combusted mixture must be expanded to an area larger than the incoming stream to provide thrust. Since a conventional nozzle would be too large, the entire lower after body of the vehicle is used as an expansion surface. Because of the high external temperatures seen during atmospheric flight, the design of an airbreathing SSTO vehicle requires delicate tradeoffs between engine design, vehicle shape, and thermal protection system (TPS) sizing in order to produce an optimum system in terms of weight (and cost) and maximum performance.

NASA Aircraft Vortex Spacing System Development Status

NASA Technical Reports Server (NTRS)

Hinton, David A.; Charnock, James K.; Bagwell, Donald R.; Grigsby, Donner

1999-01-01

The National Aeronautics and Space Administration (NASA) is addressing airport capacity enhancements during instrument meteorological conditions through the Terminal Area Productivity (TAP) program. Within TAP, the Reduced Spacing Operations (RSO) subelement at the NASA Langley Research Center is developing an Aircraft VOrtex Spacing System (AVOSS). AVOSS will integrate the output of several systems to produce weather dependent, dynamic wake vortex spacing criteria. These systems provide current and predicted weather conditions, models of wake vortex transport and decay in these weather conditions, and real-time feedback of wake vortex behavior from sensors. The goal of the NASA program is to provide the research and development to demonstrate an engineering model AVOSS in real-time operation at a major airport. The demonstration is only of concept feasibility, and additional effort is required to deploy an operational system for actual aircraft spacing reduction. This paper describes the AVOSS system architecture, a wake vortex facility established at the Dallas-Fort Worth International Airport (DFW), initial operational experience with the AVOSS system, and emerging considerations for subsystem requirements. Results of the initial system operation suggest a significant potential for reduced spacing.

United Stirling's Solar Engine Development: the Background for the Vanguard Engine

NASA Technical Reports Server (NTRS)

Holgersson, S.

1984-01-01

The development and testing resulting in the Vanguard engine and some of the characteristics of the Stirling engine based power conversion unit are described. The major part of the solar engine development is concentrated to the three different areas, the receiver, the lubrication system and the control system. Five engines are on test within the solar project. The function of the components are validated in actual solar tests.

Application of historical mobility testing to sensor-based robotic performance

NASA Astrophysics Data System (ADS)

Willoughby, William E.; Jones, Randolph A.; Mason, George L.; Shoop, Sally A.; Lever, James H.

2006-05-01

The USA Engineer Research and Development Center (ERDC) has conducted on-/off-road experimental field testing with full-sized and scale-model military vehicles for more than fifty years. Some 4000 acres of local terrain are available for tailored field evaluations or verification/validation of future robotic designs in a variety of climatic regimes. Field testing and data collection procedures, as well as techniques for quantifying terrain in engineering terms, have been developed and refined into algorithms and models for predicting vehicle-terrain interactions and resulting forces or speeds of military-sized vehicles. Based on recent experiments with Matilda, Talon, and Pacbot, these predictive capabilities appear to be relevant to most robotic systems currently in development. Utilization of current testing capabilities with sensor-based vehicle drivers, or use of the procedures for terrain quantification from sensor data, would immediately apply some fifty years of historical knowledge to the development, refinement, and implementation of future robotic systems. Additionally, translation of sensor-collected terrain data into engineering terms would allow assessment of robotic performance a priori deployment of the actual system and ensure maximum system performance in the theater of operation.

Dynamic Test Bed Analysis of Gas Energy Balance for a Diesel Exhaust System Fit with a Thermoelectric Generator

NASA Astrophysics Data System (ADS)

Fuc, Pawel; Lijewski, Piotr; Ziolkowski, Andrzej; Dobrzyński, Michal

2017-05-01

Analysis of the energy balance for an exhaust system of a diesel engine fit with an automotive thermoelectric generator (ATEG) of our own design has been carried out. A special measurement system and dedicated software were developed to measure the power generated by the modules. The research object was a 1.3-l small diesel engine with power output of 66 kW. The tests were carried out on a dynamic engine test bed that allows reproduction of an actual driving cycle expressed as a function V = f( t), simulating drivetrain (clutch, transmission) operating characteristics, vehicle geometrical parameters, and driver behavior. Measurements of exhaust gas thermodynamic parameters (temperature, pressure, and mass flow) as well as the voltage and current generated by the thermoelectric modules were performed during tests of our own design. Based on the results obtained, the flow of exhaust gas energy in the entire exhaust system was determined along with the ATEG power output. The ideal area of the exhaust system for location of the ATEG was defined to ensure the highest thermal energy recovery efficiency.

Improved imaging algorithm for bridge crack detection

NASA Astrophysics Data System (ADS)

Lu, Jingxiao; Song, Pingli; Han, Kaihong

2012-04-01

This paper present an improved imaging algorithm for bridge crack detection, through optimizing the eight-direction Sobel edge detection operator, making the positioning of edge points more accurate than without the optimization, and effectively reducing the false edges information, so as to facilitate follow-up treatment. In calculating the crack geometry characteristics, we use the method of extracting skeleton on single crack length. In order to calculate crack area, we construct the template of area by making logical bitwise AND operation of the crack image. After experiment, the results show errors of the crack detection method and actual manual measurement are within an acceptable range, meet the needs of engineering applications. This algorithm is high-speed and effective for automated crack measurement, it can provide more valid data for proper planning and appropriate performance of the maintenance and rehabilitation processes of bridge.

Experimental evaluation of automotive air-conditioning using HFC-134a and HC-134a

NASA Astrophysics Data System (ADS)

Nasution, Henry; Zainudin, Muhammad Amir; Aziz, Azhar Abdul; Latiff, Zulkarnain Abdul; Perang, Mohd Rozi Mohd; Rahman, Abd Halim Abdul

2012-06-01

An experimental study to evaluate the energy consumption of an automotive air conditioning is presented. In this study, these refrigerants will be tested using the experimental rig which simulated the actual cars as a cabin complete with a cooling system component of the actual car that is as the blower, evaporator, condenser, radiators, electric motor, which acts as a vehicle engine, and then the electric motor will operate the compressor using a belt and pulley system, as well as to the alternator will recharge the battery. The compressor working with the fluids HFC-134a and HC-134a and has been tested varying the speed in the range 1000, 1500, 2000 and 2500 rpm. The measurements taken during the one hour experimental periods at 2-minutes interval times for temperature setpoint of 20°C with internal heat loads 0, 500, 700 and 1000 W. The final results of this study show an overall better energy consumption of the HFC-134a compared with the HC-134a.

Project CAD as of July 1978: CAD support project, situation in July 1978

NASA Technical Reports Server (NTRS)

Boesch, L.; Lang-Lendorff, G.; Rothenberg, R.; Stelzer, V.

1979-01-01

The structure of Computer Aided Design (CAD) and the requirements for program developments in past and future are described. The actual standard and the future aims of CAD programs are presented. The developed programs in: (1) civil engineering; (2) mechanical engineering; (3) chemical engineering/shipbuilding; (4) electrical engineering; and (5) general programs are discussed.

How the Discovery Channel Television Show "Mythbusters" Accurately Depicts Science and Engineering Culture

ERIC Educational Resources Information Center

Zavrel, Erik A.

2011-01-01

High school science teachers, of course, want to motivate their students to consider studying science and engineering (S&E) in college. However, many high school students are not familiar with what science and engineering actually entail. They may know science as little more than "systematic discovery" and engineering as nothing but…

Which Techno-Mathematical Literacies Are Essential for Future Engineers?

ERIC Educational Resources Information Center

van der Wal, Nathalie J.; Bakker, Arthur; Drijvers, Paul

2017-01-01

Due to increased use of technology, the workplace practices of engineers have changed. So-called techno-mathematical literacies (TmL) are necessary for engineers of the 21st century. Because it is still unknown which TmL engineers actually use in their professional practices, the purpose of this study was to identify these TmL. Fourteen…

Effects from past solid waste disposal practices.

PubMed Central

Johnson, L J; Daniel, D E; Abeele, W V; Ledbetter, J O; Hansen, W R

1978-01-01

This paper reviews documented environmental effects experience from the disposal of solid waste materials in the U.S. Selected case histories are discussed that illustrate waste migration and its actual or potential effects on human or environmental health. Principal conclusions resulting from this review were: solid waste materials do migrate beyond the geometric confines of the initial placement location; environmental effects have been experienced from disposal of municipal, agricultural, and toxic chemical wastes; and utilization of presently known science and engineering principles in sitting and operating solid waste disposal facilities would make a significant improvement in the containment capability of shallow land disposal facilities. PMID:367769

Composite sizing and ply orientation for stiffness requirements using a large finite element structural model

NASA Technical Reports Server (NTRS)

Radovcich, N. A.; Gentile, D. P.

1989-01-01

A NASTRAN bulk dataset preprocessor was developed to facilitate the integration of filamentary composite laminate properties into composite structural resizing for stiffness requirements. The NASCOMP system generates delta stiffness and delta mass matrices for input to the flutter derivative program. The flutter baseline analysis, derivative calculations, and stiffness and mass matrix updates are controlled by engineer defined processes under an operating system called CBUS. A multi-layered design variable grid system permits high fidelity resizing without excessive computer cost. The NASCOMP system uses ply layup drawings for basic input. The aeroelastic resizing for stiffness capability was used during an actual design exercise.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alptekin, Gokhan

The overall objective of the proposed research is to develop a low cost, high capacity CO{sub 2} sorbent and demonstrate its technical and economic viability for pre-combustion CO{sub 2} capture. The specific objectives supporting our research plan were to optimize the chemical structure and physical properties of the sorbent, scale-up its production using high throughput manufacturing equipment and bulk raw materials and then evaluate its performance, first in bench-scale experiments and then in slipstream tests using actual coal-derived synthesis gas. One of the objectives of the laboratory-scale evaluations was to demonstrate the life and durability of the sorbent for overmore » 10,000 cycles and to assess the impact of contaminants (such as sulfur) on its performance. In the field tests, our objective was to demonstrate the operation of the sorbent using actual coal-derived synthesis gas streams generated by air-blown and oxygen-blown commercial and pilot-scale coal gasifiers (the CO{sub 2} partial pressure in these gas streams is significantly different, which directly impacts the operating conditions hence the performance of the sorbent). To support the field demonstration work, TDA collaborated with Phillips 66 and Southern Company to carry out two separate field tests using actual coal-derived synthesis gas at the Wabash River IGCC Power Plant in Terre Haute, IN and the National Carbon Capture Center (NCCC) in Wilsonville, AL. In collaboration with the University of California, Irvine (UCI), a detailed engineering and economic analysis for the new CO{sub 2} capture system was also proposed to be carried out using Aspen PlusTM simulation software, and estimate its effect on the plant efficiency.« less

On the estimation algorithm used in adaptive performance optimization of turbofan engines

NASA Technical Reports Server (NTRS)

Espana, Martin D.; Gilyard, Glenn B.

1993-01-01

The performance seeking control algorithm is designed to continuously optimize the performance of propulsion systems. The performance seeking control algorithm uses a nominal model of the propulsion system and estimates, in flight, the engine deviation parameters characterizing the engine deviations with respect to nominal conditions. In practice, because of measurement biases and/or model uncertainties, the estimated engine deviation parameters may not reflect the engine's actual off-nominal condition. This factor has a necessary impact on the overall performance seeking control scheme exacerbated by the open-loop character of the algorithm. The effects produced by unknown measurement biases over the estimation algorithm are evaluated. This evaluation allows for identification of the most critical measurements for application of the performance seeking control algorithm to an F100 engine. An equivalence relation between the biases and engine deviation parameters stems from an observability study; therefore, it is undecided whether the estimated engine deviation parameters represent the actual engine deviation or whether they simply reflect the measurement biases. A new algorithm, based on the engine's (steady-state) optimization model, is proposed and tested with flight data. When compared with previous Kalman filter schemes, based on local engine dynamic models, the new algorithm is easier to design and tune and it reduces the computational burden of the onboard computer.

Thermal/Fluid Analysis of a Composite Heat Exchanger for Use on the RLV Rocket Engine

NASA Technical Reports Server (NTRS)

Nguyen, Dalton

2002-01-01

As part of efforts to design a regeneratively cooled composite nozzle ramp for use on the reusable vehicle (RLV) rocket engine, an C-SiC composites heat exchanger concept was proposed for thermal performance evaluation. To test the feasibility of the concept, sample heat exchanger panels were made to fit the Glenn Research Center's cell 22 for testing. Operation of the heat exchanger was demonstrated in a combustion environment with high heat fluxes similar to the RLV Aerospike Ramp. Test measurements were reviewed and found to be valuable for the on going fluid and thermal analysis of the actual RLV composite ramp. Since the cooling fluid for the heat exchanger is water while the RLV Ramp cooling fluid is LH2, fluid and thermal models were constructed to correlate to the specific test set-up. The knowledge gained from this work will be helpful for analyzing the thermal response of the actual RLV Composite Ramp. The coolant thermal properties for the models are taken from test data. The heat exchanger's cooling performance was analyzed using the Generalized Fluid System Simulation Program (GFSSP). Temperatures of the heat exchanger's structure were predicted in finite element models using Patran and Sinda. Results from the analytical models and the tests show that RSC's heat exchanger satisfied the combustion environments in a series of 16 tests.

Thermal/Fluid Analysis of a Composite Heat Exchanger for Use on the RLV Rocket Engine

NASA Technical Reports Server (NTRS)

Nguyen, Dalton; Turner, Larry D. (Technical Monitor)

2001-01-01

As part of efforts to design a regeneratively cooled composite nozzle ramp for use on the reusable vehicle (RLV) rocket engine, a C-SiC composite heat exchanger concept was proposed for thermal performance evaluation. To test the feasibility of the concept, sample heat exchanger panels were made to fit the Glenn Research Center's cell 22 for testing. Operation of the heat exchanger was demonstrated in a combustion environment with high heat fluxes similar to the RLV Aerospike Ramp. Test measurements were reviewed and found to be valuable for the on-going fluid and thermal analysis of the actual RLV composite ramp. Since the cooling fluid for the heat exchanger is water while the RLV Ramp cooling fluid is LH2, fluid and therma models were constructed to correlate to the specific test set-up. The knowledge gained from this work will be helpful for analyzing the thermal response of the actual RLV Composite Ramp. The coolant thermal properties for the models are taken from test data. The heat exchanger's cooling performance was analyzed using the Generalized Fluid System Simulation Program (GFSSP). Temperatures of the heat exchanger's structure were predicted in finite element models using Patran and Sinda. Results from the analytical models and the tests show that RSC's heat exchanger satisfied the combustion environments in a series of 16 tests.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hooker, J.N.

This report describes an investigation of energy consumption and efficiency of oil pipelines in the US in 1978. It is based on a simulation of the actual movement of oil on a very detailed representation of the pipeline network, and it uses engineering equations to calculate the energy that pipeline pumps must have exerted on the oil to move it in this manner. The efficiencies of pumps and drivers are estimated so as to arrive at the amount of energy consumed at pumping stations. The throughput in each pipeline segment is estimated by distributing each pipeline company's reported oil movementsmore » over its segments in proportions predicted by regression equations that show typical throughput and throughput capacity as functions of pipe diameter. The form of the equations is justified by a generalized cost-engineering study of pipelining, and their parameters are estimated using new techniques developed for the purpose. A simplified model of flow scheduling is chosen on the basis of actual energy use data obtained from a few companies. The study yields energy consumption and intensiveness estimates for crude oil trunk lines, crude oil gathering lines and oil products lines, for the nation as well as by state and by pipe diameter. It characterizes the efficiency of typical pipelines of various diameters operating at capacity. Ancillary results include estimates of oil movements by state and by diameter and approximate pipeline capacity utilization nationwide.« less

Development of engineering drawing ability for emerging engineering education

NASA Astrophysics Data System (ADS)

Guo, Jian-Wen; Cao, Xiao-Chang; Xie, Li; Jin, Jian-Jun; Wang, Chu-Diao

2017-09-01

Students majoring in engineering is required by the emerging engineering education (3E) in the aspect of their ability of engineering drawing. This paper puts forward training mode of engineering drawing ability for 3E. This mode consists of three kinds of training including training in courses, training in competitions and training in actual demand. We also design the feasible implementation plan and supplies viable references to carry out the mode.

Unmanned aerial vehicle (UAV) application to the structural health assessment of large civil engineering structures

NASA Astrophysics Data System (ADS)

Castiglioni, Carlo A.; Rabuffetti, Angelo S.; Chiarelli, Gian P.; Brambilla, Giovanni; Georgi, Julia

2017-09-01

This paper summarizes the experience gained in the structural assessment of an existing Thermal Power Plant (TPP) located near Pristina, focusing on the cooling tower and the flue gas stack, which are the main structures of the TPP. Scope of the work was the evaluation of the actual conditions of the structures and to identify the eventual repair measures in order to guarantee a safe and reliable operation of the TPP in view of the extension of its operational lifetime for the next 30 years. With this aim, a sequence of different activities was performed, like: a topographic survey to compare the actual geometrical configuration with the design one, an investigation of the material properties, an in depth visual inspection in order to detect any visible existing damage. Due to the very high elevations of the constructions and to the lack of appropriate structures aimed to their inspections and maintenance, this activity could not be performed without using Unmanned Aerial Vehicle (UAV). This resulted the safest, most economical and less time-consuming solution identified to map the surface damage in the reinforced concrete elements of these large structures including zones that could not be inspected because out of reach by other means.

Facility design, construction, and operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

France has been disposing of low-level radioactive waste (LLW) at the Centre de Stockage de la Manche (CSM) since 1969 and now at the Centre de Stockage de l`Aube (CSA) since 1992. In France, several agencies and companies are involved in the development and implementation of LLW technology. The Commissariat a l`Energie Atomic (CEA), is responsible for research and development of new technologies. The Agence National pour la Gestion des Dechets Radioactifs is the agency responsible for the construction and operation of disposal facilities and for wastes acceptance for these facilities. Compagnie Generale des Matieres Nucleaires provides fuel services, includingmore » uranium enrichment, fuel fabrication, and fuel reprocessing, and is thus one generator of LLW. Societe pour les Techniques Nouvelles is an engineering company responsible for commercializing CEA waste management technology and for engineering and design support for the facilities. Numatec, Inc. is a US company representing these French companies and agencies in the US. In Task 1.1 of Numatec`s contract with Martin Marietta Energy Systems, Numatec provides details on the design, construction and operation of the LLW disposal facilities at CSM and CSA. Lessons learned from operation of CSM and incorporated into the design, construction and operating procedures at CSA are identified and discussed. The process used by the French for identification, selection, and evaluation of disposal technologies is provided. Specifically, the decisionmaking process resulting in the change in disposal facility design for the CSA versus the CSM is discussed. This report provides` all of the basic information in these areas and reflects actual experience to date.« less

Actualization of Competencies of Graduates-Engineers in Russia

ERIC Educational Resources Information Center

Ivashova, Valentina A.; Dub, Galina V.; Kenina, Diana S.; Kosintseva, Yulia F.; Migatcheva, Marina V.

2016-01-01

The article presents the results of the empirical research relevant to the labor market competencies of graduates with the major in engineering. Subjective preferences of employers shape requirements for the personal and professional characteristics of a graduate. In authors' opinion, the professional competences of engineers stated in educational…

Women in Engineering: Educational Concomitants of a Non-Traditional Career Choice.

ERIC Educational Resources Information Center

Evetts, Julia

1993-01-01

Uses career history data from 15 women in professional engineering careers to examine some educational concomitants of nontraditional career choices. The focus, from an interactionist theoretical perspective, is on how women actually experienced becoming an engineer. The educational influences identified are those perceived by women themselves to…

Fire protection for launch facilities using machine vision fire detection

NASA Astrophysics Data System (ADS)

Schwartz, Douglas B.

1993-02-01

Fire protection of critical space assets, including launch and fueling facilities and manned flight hardware, demands automatic sensors for continuous monitoring, and in certain high-threat areas, fast-reacting automatic suppression systems. Perhaps the most essential characteristic for these fire detection and suppression systems is high reliability; in other words, fire detectors should alarm only on actual fires and not be falsely activated by extraneous sources. Existing types of fire detectors have been greatly improved in the past decade; however, fundamental limitations of their method of operation leaves open a significant possibility of false alarms and restricts their usefulness. At the Civil Engineering Laboratory at Tyndall Air Force Base in Florida, a new type of fire detector is under development which 'sees' a fire visually, like a human being, and makes a reliable decision based on known visual characteristics of flames. Hardware prototypes of the Machine Vision (MV) Fire Detection System have undergone live fire tests and demonstrated extremely high accuracy in discriminating actual fires from false alarm sources. In fact, this technology promises to virtually eliminate false activations. This detector could be used to monitor fueling facilities, launch towers, clean rooms, and other high-value and high-risk areas. Applications can extend to space station and in-flight shuttle operations as well; fiber optics and remote camera heads enable the system to see around obstructed areas and crew compartments. The capability of the technology to distinguish fires means that fire detection can be provided even during maintenance operations, such as welding.

Fire protection for launch facilities using machine vision fire detection

NASA Technical Reports Server (NTRS)

Schwartz, Douglas B.

1993-01-01

Fire protection of critical space assets, including launch and fueling facilities and manned flight hardware, demands automatic sensors for continuous monitoring, and in certain high-threat areas, fast-reacting automatic suppression systems. Perhaps the most essential characteristic for these fire detection and suppression systems is high reliability; in other words, fire detectors should alarm only on actual fires and not be falsely activated by extraneous sources. Existing types of fire detectors have been greatly improved in the past decade; however, fundamental limitations of their method of operation leaves open a significant possibility of false alarms and restricts their usefulness. At the Civil Engineering Laboratory at Tyndall Air Force Base in Florida, a new type of fire detector is under development which 'sees' a fire visually, like a human being, and makes a reliable decision based on known visual characteristics of flames. Hardware prototypes of the Machine Vision (MV) Fire Detection System have undergone live fire tests and demonstrated extremely high accuracy in discriminating actual fires from false alarm sources. In fact, this technology promises to virtually eliminate false activations. This detector could be used to monitor fueling facilities, launch towers, clean rooms, and other high-value and high-risk areas. Applications can extend to space station and in-flight shuttle operations as well; fiber optics and remote camera heads enable the system to see around obstructed areas and crew compartments. The capability of the technology to distinguish fires means that fire detection can be provided even during maintenance operations, such as welding.

Kuwaiti Engineers' Perspectives of the Engineering Senior Design (Capstone) Course as Related to Their Professional Experiences

ERIC Educational Resources Information Center

AlSagheer, Abdullah

2010-01-01

This study looks into transfer of learning and its application in the actual employment of engineering students after graduation. At Kuwait University, a capstone course is being offered that aims to ensure that students amalgamate all kinds of engineering skills to apply to their work. Within a basic interpretive, qualitative study-design…

Flight Hydrogen Sensor for use in the ISS Oxygen Generation Assembly

NASA Technical Reports Server (NTRS)

MSadoques, George, Jr.; Makel, Darby B.

2005-01-01

This paper provides a description of the hydrogen sensor Orbital Replacement Unit (ORU) used on the Oxygen Generation Assembly (OGA), to be operated on the International Space Station (ISS). The hydrogen sensor ORU is being provided by Makel Engineering, Inc. (MEI) to monitor the oxygen outlet for the presence of hydrogen. The hydrogen sensor ORU is a triple redundant design where each sensor converts raw measurements to actual hydrogen partial pressure that is reported to the OGA system controller. The signal outputs are utilized for system shutdown in the event that the hydrogen concentration in the oxygen outlet line exceeds the specified shutdown limit. Improvements have been made to the Micro-Electro-Mechanical Systems (MEMS) based sensing element, screening, and calibration process to meet OGA operating requirements. Two flight hydrogen sensor ORUs have successfully completed the acceptance test phase. This paper also describes the sensor s performance during acceptance testing, additional tests planned to extend the operational performance calibration cycle, and integration with the OGA system.

Overview of the Microgravity Science Glovebox (MSG) Facility and the Research Performed in the MSG

NASA Technical Reports Server (NTRS)

Jordan, Lee

2016-01-01

The Microgravity Science Glovebox (MSG) is a rack facility aboard the International Space Station (ISS) designed for investigation handling. The MSG was built by the European Space Agency (ESA) which also provides sustaining engineering support for the facility. The MSG has been operating on the ISS since July 2002 and is currently located in the US Laboratory Module. The unique design of the facility allows it to accommodate science and technology investigations in a "workbench" type environment. The facility has an enclosed working volume that is held at a negative pressure with respect to the crew living area. This allows the facility to provide two levels of containment for small parts, particulates, fluids, and gases. This containment approach protects the crew from possible hazardous operations that take place inside the MSG work volume. Research investigations operating inside the MSG are provided a large 255 liter enclosed work space, 1000 watts of direct current power via a versatile supply interface (120, 28, plus or minus 12, and 5 volts direct current), 1000 watts of cooling capability, video and data recording and real time downlink, ground commanding capabilities, access to ISS Vacuum Exhaust and Vacuum Resource Systems, and gaseous nitrogen supply. These capabilities make the MSG one of the most utilized facilities on ISS. The MSG has been used for over 27,000 hours of scientific payload operations. MSG investigations involve research in cryogenic fluid management, fluid physics, spacecraft fire safety, materials science, combustion, plant growth, biological studies and life support technology. The MSG facility is operated by the Payloads Operations Integration Center at Marshall Space Flight Center. Payloads may also operate remotely from different telescience centers located in the United States and Europe. The Investigative Payload Integration Manager (IPIM) is the focal to assist organizations that have payloads operating in the MSG facility. NASA provides an MSG engineering unit for payload developers to verify that their hardware is operating properly before actual operation on the ISS. This poster will provide an overview of the MSG facility, a synopsis of the research that has already been accomplished in the MSG, and an overview of video and biological upgrades. The author would like to acknowledge Teledyne Brown Engineering and the entire MSG Team for their inputs into this poster.

Scenario analysis for techno-economic model development of U.S. offshore wind support structures

DOE PAGES

Damiani, Rick; Ning, Andrew; Maples, Ben; ...

2016-09-22

Challenging bathymetry and soil conditions of future US offshore wind power plants might promote the use of multimember, fixed-bottom structures (or 'jackets') in place of monopiles. Support structures affect costs associated with the balance of system and operation and maintenance. Understanding the link between these costs and the main environmental design drivers is crucial in the quest for a lower levelized cost of energy, and it is the main rationale for this work. Actual cost and engineering data are still scarce; hence, we evaluated a simplified engineering approach to tie key site and turbine parameters (e.g. water depth, wave height,more » tower-head mass, hub height and generator rating) to the overall support weight. A jacket-and-tower sizing tool, part of the National Renewable Energy Laboratory's system engineering software suite, was utilized to achieve mass-optimized support structures for 81 different configurations. This tool set provides preliminary sizing of all jacket components. Results showed reasonable agreement with the available industry data, and that the jacket mass is mainly driven by water depth, but hub height and tower-head mass become more influential at greater turbine ratings. A larger sensitivity of the structural mass to wave height and target eigenfrequency was observed for the deepest water conditions (>40 m). Thus, techno-economic analyses using this model should be based on accurate estimates of actual metocean conditions and turbine parameters especially for deep waters. Finally, the relationships derived from this study will inform National Renewable Energy Laboratory's offshore balance of system cost model, and they will be used to evaluate the impact of changes in technology on offshore wind lower levelized cost of energy.« less

An Operating Method Using Prediction of Photovoltaic Power for a Photovoltaic-Diesel Hybrid Power Generation System

NASA Astrophysics Data System (ADS)

Yamamoto, Shigehiro; Sumi, Kazuyoshi; Nishikawa, Eiichi; Hashimoto, Takeshi

This paper describes a novel operating method using prediction of photovoltaic (PV) power for a photovoltaic-diesel hybrid power generation system. The system is composed of a PV array, a storage battery, a bi-directional inverter and a diesel engine generator (DG). The proposed method enables the system to save fuel consumption by using PV energy effectively, reducing charge and discharge energy of the storage battery, and avoiding low-load operation of the DG. The PV power is simply predicted from a theoretical equation of solar radiation and the observed PV energy for a constant time before the prediction. The amount of fuel consumption of the proposed method is compared with that of other methods by a simulation based on measurement data of the PV power at an actual PV generation system for one year. The simulation results indicate that the amount of fuel consumption of the proposed method is smaller than that of any other methods, and is close to that of the ideal operation of the DG.

Prospects of microbial cell factories developed through systems metabolic engineering.

PubMed

Gustavsson, Martin; Lee, Sang Yup

2016-09-01

While academic-level studies on metabolic engineering of microorganisms for production of chemicals and fuels are ever growing, a significantly lower number of such production processes have reached commercial-scale. In this work, we review the challenges associated with moving from laboratory-scale demonstration of microbial chemical or fuel production to actual commercialization, focusing on key requirements on the production organism that need to be considered during the metabolic engineering process. Metabolic engineering strategies should take into account techno-economic factors such as the choice of feedstock, the product yield, productivity and titre, and the cost effectiveness of midstream and downstream processes. Also, it is important to develop an industrial strain through metabolic engineering for pathway construction and flux optimization together with increasing tolerance to products and inhibitors present in the feedstock, and ensuring genetic stability and strain robustness under actual fermentation conditions. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Real-time gaseous, PM and ultrafine particle emissions from a modern marine engine operating on biodiesel.

PubMed

Jayaram, Varalakshmi; Agrawal, Harshit; Welch, William A; Miller, J Wayne; Cocker, David R

2011-03-15

Emissions from harbor-craft significantly affect air quality in populated regions near ports and inland waterways. This research measured regulated and unregulated emissions from an in-use EPA Tier 2 marine propulsion engine on a ferry operating in a bay following standard methods. A special effort was made to monitor continuously both the total Particulate Mass (PM) mass emissions and the real-time Particle Size Distribution (PSD). The engine was operated following the loads in ISO 8178-4 E3 cycle for comparison with the certification standards and across biodiesel blends. Real-time measurements were also made during a typical cruise in the bay. Results showed the in-use nitrogen oxide (NOx) and PM(2.5) emission factors were within the not to exceed standard for Tier 2 marine engines. Comparing across fuels we observed the following: a) no statistically significant change in NO(x) emissions with biodiesel blends (B20, B50); b) ∼ 16% and ∼ 25% reduction of PM(2.5) mass emissions with B20 and B50 respectively; c) a larger organic carbon (OC) to elemental carbon (EC) ratio and organic mass (OM) to OC ratio with B50 compared to B20 and B0; d) a significant number of ultrafine nuclei and a smaller mass mean diameter with increasing blend-levels of biodiesel. The real-time monitoring of gaseous and particulate emissions during a typical cruise in the San Francisco Bay (in-use cycle) revealed important effects of ocean/bay currents on emissions: NO(x) and CO(2) increased 3-fold; PM(2.5) mass increased 6-fold; and ultrafine particles disappeared due to the effect of bay currents. This finding has implications on the use of certification values instead of actual in-use emission values when developing inventories. Emission factors for some volatile organic compounds (VOCs), carbonyls, and poly aromatic hydrocarbons (PAHs) are reported as supplemental data.

Student Participation in Rover Field Trials

NASA Astrophysics Data System (ADS)

Bowman, C. D.; Arvidson, R. E.; Nelson, S. V.; Sherman, D. M.; Squyres, S. W.

2001-12-01

The LAPIS program was developed in 1999 as part of the Athena Science Payload education and public outreach, funded by the JPL Mars Program Office. For the past three years, the Athena Science Team has been preparing for 2003 Mars Exploration Rover Mission operations using the JPL prototype Field Integrated Design and Operations (FIDO) rover in extended rover field trials. Students and teachers participating in LAPIS work with them each year to develop a complementary mission plan and implement an actual portion of the annual tests using FIDO and its instruments. LAPIS is designed to mirror an end-to-end mission: Small, geographically distributed groups of students form an integrated mission team, working together with Athena Science Team members and FIDO engineers to plan, implement, and archive a two-day test mission, controlling FIDO remotely over the Internet using the Web Interface for Telescience (WITS) and communicating with each other by email, the web, and teleconferences. The overarching goal of LAPIS is to get students excited about science and related fields. The program provides students with the opportunity to apply knowledge learned in school, such as geometry and geology, to a "real world" situation and to explore careers in science and engineering through continuous one-on-one interactions with teachers, Athena Science Team mentors, and FIDO engineers. A secondary goal is to help students develop improved communication skills and appreciation of teamwork, enhanced problem-solving skills, and increased self-confidence. The LAPIS program will provide a model for outreach associated with future FIDO field trials and the 2003 Mars mission operations. The base of participation will be broadened beyond the original four sites by taking advantage of the wide geographic distribution of Athena team member locations. This will provide greater numbers of students with the opportunity to actively engage in rover testing and to explore the possibilities of science, engineering, and technology.

An assessment of cruise NOx emissions of short-haul commercial flights

NASA Astrophysics Data System (ADS)

Turgut, Enis T.; Usanmaz, Oznur

2017-12-01

Cruise NOx emissions of aircraft are an important input parameter for studies investigating climate change due to their ability to alter the concentrations of certain trace gases, such as ozone, methane, and hydroxyl in the atmosphere, and to induce positive radiative forcing. Therefore, it is of importance to minimize estimation errors on NOx emitted from aircraft engines at high altitude. In this study, the cruise NOx emissions of a frequently-used narrow-bodied aircraft type operating domestic flights in Turkey, are quantified based on numerous actual flight, actual emissions and actual meteorological data. The overall average cruise NOx emissions index is found to be ∼10 g/kg fuel. In addition, newly-developed parameters of the aircraft cruise NOx footprint and NOx intensity are calculated to be 0.5 g/pa-NM and ∼60 g/NM, respectively. Regarding the effects of flight parameters on cruise NOx emissions, while there is a distinct increase in NOx parameters with an increase in aircraft mass, this may differ for altitude. The results reveal that the NOx emissions index tends to increase slightly by 1-2%, particularly above 28,000 ft, whereas NOx intensity decreases at a rate of 2.4-2.7% per 2000 ft of cruise altitude increase.

Active control of fan noise from a turbofan engine

NASA Technical Reports Server (NTRS)

Thomas, Russell H.; Burdisso, Ricardo A.; Fuller, Christopher R.; O'Brien, Walter F.

1994-01-01

A three-channel active control system is applied to an operational turbofan engine to reduce tonal noise produced by both the fan and the high-pressure compressor. The control approach is the feedforward filtered-x least-mean-square algorithm implemented on a digital signal processing board. Reference transducers mounted on the engine case provide blade passing and harmonics frequency information to the controller. Error information is provided by large area microphones placed in the acoustic far field. To minimize the error signal, the controller actuates loudspeakers mounted on the inlet to produce destructive interference. The sound pressure level of the fundamental tone of the fan was reduced using the three-channel controller by up to 16 dB over a +/- 30-deg angle about the engine axis. A single-channel controller could produce reduction over a +/- 15-deg angle. The experimental results show the control to be robust. Outside of the areas contolled, the levels of the tone actually increased due to the generation of radial modes by the control sources. Simultaneous control of two tones is achieved with parallel controllers. The fundamental and the first harmonic tones of the fan were controlled simultaneously with reductions of 12 and 5 dBA, respectively, measured on the engine axis. Simultaneous control was also demonstrated for the fan fundamental and the high-pressure compressor fundamental tones.

Military Potential Test of the Model PA23-250B Fixed-Wing Instrument Trainer

DTIC Science & Technology

1964-11-30

cabin heater was installed in the test airplane. Existing climatic conditions precluded actual tests to determine the capability of the heater to...housed within the engine contol pedestal under the engine conr- trol levers. r , aulic pressure is supplied to the control unit by an engine-driven

NREL Bridges Fuels and Engines R&D to Maximize Vehicle Efficiency and

Science.gov Websites

innovation-from fuel chemistry, conversion, and combustion to the evaluation of advanced fuels in actual -cylinder engine for advanced compression ignition fuels research will be installed and commissioned in the vehicle performance and emissions research, two engine dynamometer test cells for advanced fuels research

STEM Teachers' Planned and Enacted Attempts at Implementing Engineering Design-Based Instruction

ERIC Educational Resources Information Center

Capobianco, Brenda M.; Rupp, Madeline

2014-01-01

This study investigates grades 5 and 6 science, technology, engineering, and mathematics (STEM) teachers' planned and actualized engineering design-based instruction, the instruments used to characterize their efforts, and the implications this work has for teachers' implementations of an integrated approach to STEM education.…

40 CFR 86.1330-90 - Test sequence; general requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... fuel and the point at which it is measured shall be specified by the manufacturer. (g) Pre-test engine...-fueled or methanol-fueled diesel engine fuel flows, etc.), pre-test engine performance checks (e.g., verification of actual rated rpm, etc.) and pre-test system calibrations (e.g., inlet and exhaust restrictions...

40 CFR 86.1330-90 - Test sequence; general requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... fuel and the point at which it is measured shall be specified by the manufacturer. (g) Pre-test engine...-fueled or methanol-fueled diesel engine fuel flows, etc.), pre-test engine performance checks (e.g., verification of actual rated rpm, etc.) and pre-test system calibrations (e.g., inlet and exhaust restrictions...

40 CFR 86.1330-90 - Test sequence; general requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... fuel and the point at which it is measured shall be specified by the manufacturer. (g) Pre-test engine...-fueled or methanol-fueled diesel engine fuel flows, etc.), pre-test engine performance checks (e.g., verification of actual rated rpm, etc.) and pre-test system calibrations (e.g., inlet and exhaust restrictions...

40 CFR 86.1330-90 - Test sequence; general requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... fuel and the point at which it is measured shall be specified by the manufacturer. (g) Pre-test engine...-fueled or methanol-fueled diesel engine fuel flows, etc.), pre-test engine performance checks (e.g., verification of actual rated rpm, etc.) and pre-test system calibrations (e.g., inlet and exhaust restrictions...

Virtue ethics, positive psychology, and a new model of science and engineering ethics education.

PubMed

Han, Hyemin

2015-04-01

This essay develops a new conceptual framework of science and engineering ethics education based on virtue ethics and positive psychology. Virtue ethicists and positive psychologists have argued that current rule-based moral philosophy, psychology, and education cannot effectively promote students' moral motivation for actual moral behavior and may even lead to negative outcomes, such as moral schizophrenia. They have suggested that their own theoretical framework of virtue ethics and positive psychology can contribute to the effective promotion of motivation for self-improvement by connecting the notion of morality and eudaimonic happiness. Thus this essay attempts to apply virtue ethics and positive psychology to science and engineering ethics education and to develop a new conceptual framework for more effective education. In addition to the conceptual-level work, this essay suggests two possible educational methods: moral modeling and involvement in actual moral activity in science and engineering ethics classes, based on the conceptual framework.

Influence of System Operation Method on CO2 Emissions of PV/Solar Heat/Cogeneration System

NASA Astrophysics Data System (ADS)

Oke, Shinichiro; Kemmoku, Yoshishige; Takikawa, Hirofumi; Sakakibara, Tateki

A PV/solar heat/cogeneration system is assumed to be installed in a hotel. The system is operated with various operation methods: CO2 minimum operation, fees minimum operation, seasonal operation, daytime operation and heat demand following operation. Of these five operations, the former two are virtual operations that are operated with the dynamic programming method, and the latter three are actual operations. Computer simulation is implemented using hourly data of solar radiation intensity, atmospheric temperature, electric, cooling, heating and hot water supply demands for one year, and the life-cycle CO2 emission and the total cost are calculated for every operations. The calculation results show that the virtual two and the actual three operations reduce the life-cycle CO2 emission by 21% and 13% compared with the conventional system, respectively. In regard to both the CO2 emission and the cost, there is no significant difference between the virtual two operation methods or among actual three operation methods.

Method for in-use measurement and evaluation of the activity, fuel use, electricity use, and emissions of a plug-in hybrid diesel-electric school bus.

PubMed

Choi, Hyung-Wook; Frey, H Christopher

2010-05-01

The purpose of this study is to demonstrate a methodology for characterizing at high resolution the energy use and emissions of a plug-in parallel-hybrid diesel-electric school bus (PHSB) to support assessments of sensitivity to driving cycles and comparisons to a conventional diesel school bus (CDSB). Data were collected using onboard instruments for a first-of-a-kind prototype PHSB and a CDSB of the same chassis and engine, operated on actual school bus routes. The engine load was estimated on the basis of vehicle specific power (VSP) and an empirically derived relationship between VSP and engine manifold absolute pressure (MAP). VSP depends on speed, acceleration, and road grade. For the PHSB, the observed electrical discharge or recharge to the traction motor battery was characterized on the basis of VSP. The energy use and emission rates of the PHSB from tailpipe and electricity use were estimated for five real-world driving cycles and compared to the engine fuel use and emissions of the CDSB. The PHSB had the greatest advantage on arterial routes and less advantage on highway or local routes. The coupled VSP-MAP modeling approach enables assessment of a wide variety of driving conditions and comparisons of vehicles with different propulsion technologies.

Interactive chemistry management system (ICMS); Field demonstration results at United Illuminating

DOE Office of Scientific and Technical Information (OSTI.GOV)

Noto, F.A.; Farrell, D.M.; Lombard, E.V.

1988-01-01

The authors report on a field demonstration of the interactive chemistry management system (ICMS) performed in the late summer of 1987 at the New Haven Harbor Station of United Illuminating Co. This demonstration was the first installation of the ICMS at an actual plant site. The ICMS is a computer-based system designed to monitor, diagnose, and provide optional automatic control of water and steam chemistry throughout the steam generator cycle. It is one of the diagnostic modules that comprises CE-TOPS (combustion engineering total on-line performance system), which continuously monitors operating conditions and suggests priority actions to increase operation efficiency, extendmore » the performance life of boiler components and reduce maintenance costs. By reducing the number of forced outages through early identification of potentially detrimental conditions, diagnosis of possible causes, and execution of corrective actions, improvements in unit availability and reliability will result.« less

Overview of the Life Science Glovebox (LSG) Facility and the Research Performed in the LSG

NASA Technical Reports Server (NTRS)

Cole, J. Michael; Young, Yancy

2016-01-01

The Life Science Glovebox (LSG) is a rack facility currently under development with a projected availability for International Space Station (ISS) utilization in the FY2018 timeframe. Development of the LSG is being managed by the Marshal Space Flight Center (MSFC) with support from Ames Research Center (ARC) and Johnson Space Center (JSC). The MSFC will continue management of LSG operations, payload integration, and sustaining following delivery to the ISS. The LSG will accommodate life science and technology investigations in a "workbench" type environment. The facility has a.Ii enclosed working volume that is held at a negative pressure with respect to the crew living area. This allows the facility to provide two levels of containment for handling Biohazard Level II and lower biological materials. This containment approach protects the crew from possible hazardous operations that take place inside the LSG work volume. Research investigations operating inside the LSG are provided approximately 15 cubic feet of enclosed work space, 350 watts of28Vdc and l IOVac power (combined), video and data recording, and real time downlink. These capabilities will make the LSG a highly utilized facility on ISS. The LSG will be used for biological studies including rodent research and cell biology. The LSG facility is operated by the Payloads Operations Integration Center at MSFC. Payloads may also operate remotely from different telescience centers located in the United States and different countries. The Investigative Payload Integration Manager (IPIM) is the focal to assist organizations that have payloads operating in the LSG facility. NASA provides an LSG qualification unit for payload developers to verify that their hardware is operating properly before actual operation on the ISS. This poster will provide an overview of the LSG facility and a synopsis of the research that will be accomplished in the LSG. The authors would like to acknowledge Ames Research Center, Johnson Space Center, Teledyne Brown Engineering, MOOG-Bradford Engineering and the entire LSG Team for their inputs into this abstract.

Boeing B-29 Superfortress at the Lewis Flight Propulsion Laboratory

NASA Image and Video Library

1947-05-21

The NACA’s Lewis Flight Propulsion Laboratory used a Boeing B-29 Superfortress as a testbed for ramjet investigations in the late 1940s. NACA Lewis conducted a wide variety of studies on ramjets to determine basic operational data necessary to design missiles. This information included the relationship between combustion chamber and inlet pressure and temperature, velocity of the fuel-air ratio to the ignition characteristics, and combustion efficiency. Although wind tunnel and test stand studies were important first steps in determining these factors, actual flight tests were required. Lewis engineers modified the B-29 so that the ramjet could be stored in the bomb bay. Once the aircraft reached the desired altitude and speed the ramjet was suspended 52 inches below the bomb bay. The ramjet’s angle-of-attack could be independently adjusted, and a periscope permitted a view of the test article from inside the aircraft. Measurements were taken in free-stream conditions between 5,000 and 30,000 feet. The test flights, which began in April 1947, were flown at speeds up to Mach 0.51 and altitudes of 5,000 to 30,000 feet. The researchers first determined that 14,000 feet was the maximum altitude at which the engine could be ignited by spark. Flares were used to start the engine at altitudes up to 30,000 feet. Overall the ramjet operated well at all speeds and altitudes. Significant changes in fuel flow were successful at lower altitudes, but produced combustion blowout above 20,000 feet.

Boeing B–29 Superfortress at the Aircraft Engine Research Laboratory

NASA Image and Video Library

1944-07-21

A Boeing B–29 Superfortress at the National Advisory Committee for Aeronautics (NACA) Aircraft Engine Research Laboratory in Cleveland, Ohio. The B–29 was the Army Air Forces’ deadliest weapon during the latter portion of World War II. The aircraft was significantly larger than previous bombers but could fly faster and higher. The B–29 was intended to soar above anti-aircraft fire and make pinpoint drops onto strategic targets. The bomber was forced to carry 20,000 pounds more armament than it was designed for. The extra weight pushed the B–29’s four powerful Wright R–3350 engines to their operating limits. The over-heating of the engines proved to be a dangerous problem. The military asked the NACA to tackle the issue. Full-scale engine tests on a R–3350 engine in the Prop House demonstrated that a NACA-designed impeller increased the flow rate of the fuel injection system. Altitude Wind Tunnel studies of the engine led to the reshaping of cowling inlet and outlet to improve airflow and reduce drag. Single-cylinder studies on valve failures were resolved by a slight extension of the cylinder head, and the Engine Research Building researchers combated uneven heating with a new fuel injection system. The modifications were then tried out on an actual B–29. The bomber arrived in Cleveland on June 22, 1944. The new injection impeller, ducted head baffles and instrumentation were installed on the bomber’s two left wing engines. Eleven test flights were flown over the next month with military pilots at the helm. Overall the flight tests corroborated the wind tunnel and test stand studies.

The Effect of Acoustic Disturbances on the Operation of the Space Shuttle Main Engine Fuel Flowmeter

NASA Technical Reports Server (NTRS)

Marcu, Bogdan; Szabo, Roland; Dorney, Dan; Zoladz, Tom

2007-01-01

The Space Shuttle Main Engine (SSME) uses a turbine fuel flowmeter (FFM) in its Low Pressure Fuel Duct (LPFD) to measure liquid hydrogen flowrates during engine operation. The flowmeter is required to provide accurate and robust measurements of flow rates ranging from 10000 to 18000 GPM in an environment contaminated by duct vibration and duct internal acoustic disturbances. Errors exceeding 0.5% can have a significant impact on engine operation and mission completion. The accuracy of each sensor is monitored during hot-fire engine tests on the ground. Flow meters which do not meet requirements are not flown. Among other parameters, the device is screened for a specific behavior in which a small shift in the flow rate reading is registered during a period in which the actual fuel flow as measured by a facility meter does not change. Such behavior has been observed over the years for specific builds of the FFM and must be avoided or limited in magnitude in flight. Various analyses of the recorded data have been made prior to this report in an effort to understand the cause of the phenomenon; however, no conclusive cause for the shift in the instrument behavior has been found. The present report proposes an explanation of the phenomenon based on interactions between acoustic pressure disturbances in the duct and the wakes produced by the FFM flow straightener. Physical insight into the effects of acoustic plane wave disturbances was obtained using a simple analytical model. Based on that model, a series of three-dimensional unsteady viscous flow computational fluid dynamics (CFD) simulations were performed using the MSFC PHANTOM turbomachinery code. The code was customized to allow the FFM rotor speed to change at every time step according to the instantaneous fluid forces on the rotor, that, in turn, are affected by acoustic plane pressure waves propagating through the device. The results of the simulations show the variation in the rotation rate of the flowmeter due to the interaction of the flow straightener wakes and the upstream propagating acoustic waves. A detailed analysis of the acoustic disturbance effects is presented along with an assessment of the impact on measurement accuracy.

Operator agency in process intervention: tampering versus application of tacit knowledge

NASA Astrophysics Data System (ADS)

Van Gestel, P.; Pons, D. J.; Pulakanam, V.

2015-09-01

Statistical process control (SPC) theory takes a negative view of adjustment of process settings, which is termed tampering. In contrast, quality and lean programmes actively encourage operators to acts of intervention and personal agency in the improvement of production outcomes. This creates a conflict that requires operator judgement: How does one differentiate between unnecessary tampering and needful intervention? Also, difficult is that operators apply tacit knowledge to such judgements. There is a need to determine where in a given production process the operators are applying tacit knowledge, and whether this is hindering or aiding quality outcomes. The work involved the conjoint application of systems engineering, statistics, and knowledge management principles, in the context of a case study. Systems engineering was used to create a functional model of a real plant. Actual plant data were analysed with the statistical methods of ANOVA, feature selection, and link analysis. This identified the variables to which the output quality was most sensitive. These key variables were mapped back to the functional model. Fieldwork was then directed to those areas to prospect for operator judgement activities. A natural conversational approach was used to determine where and how operators were applying judgement. This contrasts to the interrogative approach of conventional knowledge management. Data are presented for a case study of a meat rendering plant. The results identify specific areas where operators' tacit knowledge and mental model contribute to quality outcomes and untangles the motivations behind their agency. Also evident is how novice and expert operators apply their knowledge differently. Novices were focussed on meeting throughput objectives, and their incomplete understanding of the plant characteristics led them to inadvertently sacrifice quality in the pursuit of productivity in certain situations. Operators' responses to the plant are affected by their individual mental models of the plant, which differ between operators and have variable validity. Their behaviour is also affected by differing interpretations of how their personal agency should be applied to the achievement of production objectives. The methodology developed here is an integration of systems engineering, statistical analysis, and knowledge management. It shows how to determine where in a given production process the operator intervention is occurring, how it affects quality outcomes, and what tacit knowledge operators are using. It thereby assists the continuous quality improvement processes in a different way to SPC. A second contribution is the provision of a novel methodology for knowledge management, one that circumvents the usual codification barriers to knowledge management.

40 CFR 63.5335 - How do I determine the actual HAP loss?

Code of Federal Regulations, 2010 CFR

2010-07-01

... operation type. (2) Chemical Inventory Mass Balance. Determine the actual monthly HAP loss from your... operation. (2) For facilities using add-on emission control devices, the finish inventory log and the... National Emission Standards for Hazardous Air Pollutants for Leather Finishing Operations Compliance...

Study on the Selection of Equipment Suppliers for Wind Power Generation EPC Project

NASA Astrophysics Data System (ADS)

Yang, Yuanyue; Li, Huimin

2017-12-01

In the EPC project, the purchase cost of equipments accounted for about 60% of the total project cost, thus, the selection of equipment suppliers has an important influence on the EPC project. This paper, took EPC project for the phase I engineering of Guizhou Huaxi Yunding wind power plant as research background, constructed the evaluation index system for the selection of equipment suppliers for wind power generation EPC project from multiple perspectives, and introduced matter-element extension evaluation model to evaluate the selection of equipment suppliers for this project from the qualitative and quantitative point of view. The result is consistent with the actual situation, which verifies the validity and operability of this method.

Development of new materials for turbopump bearings

NASA Technical Reports Server (NTRS)

Maurer, R. E.; Pallini, R. A.

1985-01-01

The life requirement for the angular contact ball bearings in the Space Shuttle Main Engine (SSME) high pressure oxygen turbopump (HPOTP) is 7.5 hours. In actual operation, significantly shorter service life was experienced. The objective is to identify bearing materials and/or materials processing techniques offering signficant potential for extending HPOTP bearing performance life. Interactive thermomechanical analysis of the HPOTP bearing-shaft system was performed with the SHABERTH computer program. Bearing fatigue life, ball-race contact stress, heat generation rate, bulk ring temperatures and circumferential stress in the inner rings were quantified as functions of radial load, thrust load and ball-race contact friction. Criteria established from the output of this analysis are being used for material candidate selection.

New generation of free-piston shock tunnels

NASA Technical Reports Server (NTRS)

Morrison, W. R. B.; Stalker, R. J.; Duffin, J.

1990-01-01

Consideration is given to three free-piston driven hypersonic tunnels under construction that will greatly enhance existing test capabilities. The tunnel being built at Caltech will feature energy capabilities about 40 percent higher than those of the world's largest operational free-piston tunnel to date. The second tunnel under construction will allow full-size engine hardware at near-orbital speeds. The third facility is a high-performance expansion tube that will be capable of generating high enthalpy flows at speeds of up to 9 km/sec. It will provide flows with dissociation levels much lower than are attainable with a reflected shock tunnel, approaching actual flight conditions. A table shows the tunnels' characteristics.

Intelligent Systems Approach for Automated Identification of Individual Control Behavior of a Human Operator

NASA Technical Reports Server (NTRS)

Zaychik, Kirill B.; Cardullo, Frank M.

2012-01-01

Results have been obtained using conventional techniques to model the generic human operator?s control behavior, however little research has been done to identify an individual based on control behavior. The hypothesis investigated is that different operators exhibit different control behavior when performing a given control task. Two enhancements to existing human operator models, which allow personalization of the modeled control behavior, are presented. One enhancement accounts for the testing control signals, which are introduced by an operator for more accurate control of the system and/or to adjust the control strategy. This uses the Artificial Neural Network which can be fine-tuned to model the testing control. Another enhancement takes the form of an equiripple filter which conditions the control system power spectrum. A novel automated parameter identification technique was developed to facilitate the identification process of the parameters of the selected models. This utilizes a Genetic Algorithm based optimization engine called the Bit-Climbing Algorithm. Enhancements were validated using experimental data obtained from three different sources: the Manual Control Laboratory software experiments, Unmanned Aerial Vehicle simulation, and NASA Langley Research Center Visual Motion Simulator studies. This manuscript also addresses applying human operator models to evaluate the effectiveness of motion feedback when simulating actual pilot control behavior in a flight simulator.

A Satellite Mortality Study to Support Space Systems Lifetime Prediction

NASA Technical Reports Server (NTRS)

Fox, George; Salazar, Ronald; Habib-Agahi, Hamid; Dubos, Gregory

2013-01-01

Estimating the operational lifetime of satellites and spacecraft is a complex process. Operational lifetime can differ from mission design lifetime for a variety of reasons. Unexpected mortality can occur due to human errors in design and fabrication, to human errors in launch and operations, to random anomalies of hardware and software or even satellite function degradation or technology change, leading to unrealized economic or mission return. This study focuses on data collection of public information using, for the first time, a large, publically available dataset, and preliminary analysis of satellite lifetimes, both operational lifetime and design lifetime. The objective of this study is the illustration of the relationship of design life to actual lifetime for some representative classes of satellites and spacecraft. First, a Weibull and Exponential lifetime analysis comparison is performed on the ratio of mission operating lifetime to design life, accounting for terminated and ongoing missions. Next a Kaplan-Meier survivor function, standard practice for clinical trials analysis, is estimated from operating lifetime. Bootstrap resampling is used to provide uncertainty estimates of selected survival probabilities. This study highlights the need for more detailed databases and engineering reliability models of satellite lifetime that include satellite systems and subsystems, operations procedures and environmental characteristics to support the design of complex, multi-generation, long-lived space systems in Earth orbit.

Performance Evaluation of a High Bandwidth Liquid Fuel Modulation Valve for Active Combustion Control

NASA Technical Reports Server (NTRS)

Saus, Joseph R.; DeLaat, John C.; Chang, Clarence T.; Vrnak, Daniel R.

2012-01-01

At the NASA Glenn Research Center, a characterization rig was designed and constructed for the purpose of evaluating high bandwidth liquid fuel modulation devices to determine their suitability for active combustion control research. Incorporated into the rig s design are features that approximate conditions similar to those that would be encountered by a candidate device if it were installed on an actual combustion research rig. The characterized dynamic performance measures obtained through testing in the rig are planned to be accurate indicators of expected performance in an actual combustion testing environment. To evaluate how well the characterization rig predicts fuel modulator dynamic performance, characterization rig data was compared with performance data for a fuel modulator candidate when the candidate was in operation during combustion testing. Specifically, the nominal and off-nominal performance data for a magnetostrictive-actuated proportional fuel modulation valve is described. Valve performance data were collected with the characterization rig configured to emulate two different combustion rig fuel feed systems. Fuel mass flows and pressures, fuel feed line lengths, and fuel injector orifice size was approximated in the characterization rig. Valve performance data were also collected with the valve modulating the fuel into the two combustor rigs. Comparison of the predicted and actual valve performance data show that when the valve is operated near its design condition the characterization rig can appropriately predict the installed performance of the valve. Improvements to the characterization rig and accompanying modeling activities are underway to more accurately predict performance, especially for the devices under development to modulate fuel into the much smaller fuel injectors anticipated in future lean-burning low-emissions aircraft engine combustors.

The Use of a Parametric Feature Based CAD System to Teach Introductory Engineering Graphics.

ERIC Educational Resources Information Center

Howell, Steven K.

1995-01-01

Describes the use of a parametric-feature-based computer-aided design (CAD) System, AutoCAD Designer, in teaching concepts of three dimensional geometrical modeling and design. Allows engineering graphics to go beyond the role of documentation and communication and allows an engineer to actually build a virtual prototype of a design idea and…

40 CFR 1036.625 - In-use compliance with family emission limits (FELs).

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE HEAVY-DUTY HIGHWAY ENGINES... us to apply a higher in-use FEL for certain in-use engines, subject to the provisions of this section... higher in-use FELs to your engines, we would intend to accurately reflect the actual in-use performance...

40 CFR 1036.625 - In-use compliance with family emission limits (FELs).

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE HEAVY-DUTY HIGHWAY ENGINES... us to apply a higher in-use FEL for certain in-use engines, subject to the provisions of this section... higher in-use FELs to your engines, we would intend to accurately reflect the actual in-use performance...

40 CFR 1036.625 - In-use compliance with family emission limits (FELs).

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE HEAVY-DUTY HIGHWAY ENGINES... us to apply a higher in-use FEL for certain in-use engines, subject to the provisions of this section... higher in-use FELs to your engines, we would intend to accurately reflect the actual in-use performance...

Ultrasonic Evaluation of Fatigue Damage

NASA Astrophysics Data System (ADS)

Bayer, P.; Singher, L.; Notea, A.

2004-02-01

Despite the fact that most engineers and designers are aware of fatigue, many severe breakdowns of industrial plant and machinery still occur due to fatigue. In effect, it's been estimated that fatigue causes at least 80% of the failures in modern engineering components. From an operational point of view, the detection of fatigue damage, preferably at a very early stage, is a critically important consideration in order to prevent possible catastrophic equipment failure and associated losses. This paper describes the investigation involving the use of ultrasonic waves as a potential tool for early detection of fatigue damage. The parameters investigated were the ultrasonic wave velocities (longitudinal and transverse waves) and attenuation coefficient before fatigue damage and after progressive stages of fatigue. Although comparatively small uncertainties were observed, the feasibility of utilizing the velocity of ultrasonic waves as a fatigue monitor was barely substantiated within actual research conditions. However, careful measurements of the ultrasonic attenuation parameter had demonstrated its potential to provide an early assessment of damage during fatigue.

Enhanced Component Performance Study. Emergency Diesel Generators 1998–2013

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schroeder, John Alton

2014-11-01

This report presents an enhanced performance evaluation of emergency diesel generators (EDGs) at U.S. commercial nuclear power plants. This report evaluates component performance over time using Institute of Nuclear Power Operations (INPO) Consolidated Events Database (ICES) data from 1998 through 2013 and maintenance unavailability (UA) performance data using Mitigating Systems Performance Index (MSPI) Basis Document data from 2002 through 2013. The objective is to present an analysis of factors that could influence the system and component trends in addition to annual performance trends of failure rates and probabilities. The factors analyzed for the EDG component are the differences in failuresmore » between all demands and actual unplanned engineered safety feature (ESF) demands, differences among manufacturers, and differences among EDG ratings. Statistical analyses of these differences are performed and results showing whether pooling is acceptable across these factors. In addition, engineering analyses were performed with respect to time period and failure mode. The factors analyzed are: sub-component, failure cause, detection method, recovery, manufacturer, and EDG rating.« less

New model performance index for engineering design of control systems

NASA Technical Reports Server (NTRS)

1970-01-01

Performance index includes a model representing linear control-system design specifications. Based on a geometric criterion for approximation of the model by the actual system, the index can be interpreted directly in terms of the desired system response model without actually having the model's time response.

Students' Preconceptions and Perceptions of Science-Oriented Studies

ERIC Educational Resources Information Center

Korpershoek, Hanke; Kuyper, Hans; Bosker, Roel; van der Werf, Greetje

2013-01-01

Do non-science, technology, engineering, and mathematics (STEM) students' views about STEM studies correspond with how STEM students actually perceive these studies? This paper deals with this issue by comparing higher education students' attitudes towards STEM studies between those who actually did a STEM study and those who did not. The…

An investigation of the use of discharge valves and an intake control for improving the performance of N.A.C.A. Roots type supercharger

NASA Technical Reports Server (NTRS)

Schey, Oscar W; Wilson, Ernest E

1929-01-01

This report presents the results of an analytical investigation on the practicability of using mechanically operated discharge valves in conjunction with a manually operated intake control for improving the performance of N. A. C. A. Roots type superchargers. These valves, which may be either of the oscillating or rotating type, are placed in the discharge opening of the supercharger and are so shaped and synchronized with the supercharger impellers that they do not open until the air has been compressed to the delivery pressure. The intake control limits the quantity of air compressed to engine requirements by permitting the excess air to escape from the compression chamber before compression begins. The percentage power saving and the actual horsepower saved were computed for altitudes from 0 to 20,000 feet. These computations are based on the pressure-volume cards for the conventional and the modified roots type superchargers and on the results of laboratory tests of the conventional type. The use of discharge valves shows a power saving of approximately 26 per cent at a critical altitude of 20,000 feet. In addition, these valves reduce the amplitude of the discharge pulsations and increase the volumetric efficiency. With slow-speed roots blowers operating at high-pressure differences even better results would be expected. For aircraft engine superchargers operating at high speeds these discharge valves increase the performance as above, but have the disadvantages of increasing the weight and of adding a high-speed mechanism to a simple machine. (author)

Steam dispatching control system demonstration at Fort Benjamin Harrison. Final technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Diks, C.L.; Moshage, R.E.; Lin, M.C.

1993-07-01

Currently most Army Central steam heating systems operate by maintaining a constant steam pressure regardless of actual steam demand. This method offers some operational convenience, but is often the cause of significant energy losses. Researchers at the U.S. Army Construction Engineering Research Laboratories (USACERL) have investigated the Steam Dispatching Control System (SDCS), a control system that lowers supply steam pressure-and therefore steam temperature-to slightly above the amount needed to meet the steam demand. The lower Steam temperature and reduction in steam loss (from leaks and faulty traps) result in lower heat losses and higher energy savings. Limiting steam pressure canmore » diminish the amount of excess heat loss in the distribution system while still meeting the demand. The Army's Facilities Engineering Applications Program (FEAP) chose Fort Benjamin Harrison, IN, as the Army demonstration site for SDCS. Researchers found that use of SDCS is technically and economically viable improvement over current operating procedures. Analysis based on demonstration results show that the simple payback for SDCS is less than 1 year. The results of this demonstration are generally applicable to installations with a large central heating plant and a substantial steam distribution system. Findings, indicate that energy savings form SDCS are significant regardless of what type of fuel powers the boiler. The authors note that, during the initial evaluation of a potential SDCS application, attention must be paid to the condensate return to ensure that it will operate properly. Fort Benjamin Harrison, IN, Steam Dispatching Control System(SDCS), Central heating plants, energy conservation.« less

Comparison of Commercial Aircraft Fuel Requirements in Regards to FAR, Flight Profile Simulation, and Flight Operational Techniques

NASA Astrophysics Data System (ADS)

Heitzman, Nicholas

There are significant fuel consumption consequences for non-optimal flight operations. This study is intended to analyze and highlight areas of interest that affect fuel consumption in typical flight operations. By gathering information from actual flight operators (pilots, dispatch, performance engineers, and air traffic controllers), real performance issues can be addressed and analyzed. A series of interviews were performed with various individuals in the industry and organizations. The wide range of insight directed this study to focus on FAA regulations, airline policy, the ATC system, weather, and flight planning. The goal is to highlight where operational performance differs from design intent in order to better connect optimization with actual flight operations. After further investigation and consensus from the experienced participants, the FAA regulations do not need any serious attention until newer technologies and capabilities are implemented. The ATC system is severely out of date and is one of the largest limiting factors in current flight operations. Although participants are pessimistic about its timely implementation, the FAA's NextGen program for a future National Airspace System should help improve the efficiency of flight operations. This includes situational awareness, weather monitoring, communication, information management, optimized routing, and cleaner flight profiles like Required Navigation Performance (RNP) and Continuous Descent Approach (CDA). Working off the interview results, trade-studies were performed using an in-house flight profile simulation of a Boeing 737-300, integrating NASA legacy codes EDET and NPSS with a custom written mission performance and point-performance "Skymap" calculator. From these trade-studies, it was found that certain flight conditions affect flight operations more than others. With weather, traffic, and unforeseeable risks, flight planning is still limited by its high level of precaution. From this study, it is recommended that air carriers increase focus on defining policies like load scheduling, CG management, reduction in zero fuel weight, inclusion of performance measurement systems, and adapting to the regulations to best optimize the spirit of the requirement.. As well, air carriers should create a larger drive to implement the FAA's NextGen system and move the industry into the future.

Roles, uses, and benefits of general aviation aircraft in aerospace engineering education

NASA Technical Reports Server (NTRS)

Odonoghue, Dennis P.; Mcknight, Robert C.

1994-01-01

Many colleges and universities throughout the United States offer outstanding programs in aerospace engineering. In addition to the fundamentals of aerodynamics, propulsion, flight dynamics, and air vehicle design, many of the best programs have in the past provided students the opportunity to design and fly airborne experiments on board various types of aircraft. Sadly, however, the number of institutions offering such 'airborne laboratories' has dwindled in recent years. As a result, opportunities for students to apply their classroom knowledge, analytical skills, and engineering judgement to the development and management of flight experiments on an actual aircraft are indeed rare. One major reason for the elimination of flight programs by some institutions, particularly the smaller colleges, is the prohibitive cost of operating and maintaining an aircraft as a flying laboratory. The purpose of this paper is to discuss simple, low-cost, relevant flight experiments that can be performed using readily available general aviation aircraft. This paper examines flight experiments that have been successfully conducted on board the NASA Lewis Research Center's T-34B aircraft, as part of the NASA/AIAA/University Flight Experiment Program for Students (NAUFEPS) and discusses how similar experiments could be inexpensively performed on other general aviation aircraft.

Phase 1 Space Fission Propulsion System Testing and Development Progress

NASA Technical Reports Server (NTRS)

VanDyke, Melissa; Houts, Mike; Godfroy, Tom; Dickens, Ricky; Poston, David; Kapernick, Rick; Reid, Bob; Salvail, Pat; Ring, Peter; Schafer, Charles (Technical Monitor)

2001-01-01

Successful development of space fission systems requires an extensive program of affordable and realistic testing. In addition to tests related to design/development of the fission system, realistic testing of the actual flight unit must also be performed. If the system is designed to operate within established radiation damage and fuel burn up limits while simultaneously being designed to allow close simulation of heat from fission using resistance heaters, high confidence in fission system performance and lifetime can be attained through a series of non-nuclear tests. The Safe Affordable Fission Engine (SAFE) test series, whose ultimate goal is the demonstration of a 300 kW flight configuration system, has demonstrated that realistic testing can be performed using non-nuclear methods. This test series, carried out in collaboration with other NASA centers, other government agencies, industry, and universities, successfully completed a testing program with a 30 kWt core, Stirling engine, and ion engine configuration. Additionally, a 100 kWt core is in fabrication and appropriate test facilities are being reconfigured. This paper describes the current SAFE non-nuclear tests, which includes test article descriptions, test results and conclusions, and future test plans.

Emissions from in-use lawn-mowers in Australia

NASA Astrophysics Data System (ADS)

Priest, M. W.; Williams, D. J.; Bridgman, H. A.

Concern over the levels of pollutants emitted from small engines has led to recent legislation in the United States that regulates exhaust emissions from lawn and garden equipment. Particular attention has focused on the high levels of hydrocarbons emitted by these engines. The present study establishes emission factors for lawn-mowers in use in Australia. The estimates were calculated on the basis of a series of controlled emission tests conducted on commonly used lawn-mowers. Ten two-stroke and six four-stroke lawn-mower engines were operated under simulated power requirements while fuel usage and gas emissions were monitored. Fuel consumption rates from the tests were compared to those ascertained under actual mowing conditions in field tests conducted on 19 two-stroke and ten four-stroke lawn-mowers. Basic emission factors were established for CO, CO 2, CH 4, NMHC and NO x, and combined with data on machine population and annual usage collected in a survey of lawn care practices and lawn-mower usage conducted in the Newcastle area. When compared to transport sources in the Newcastle study region, lawn-mowers contribute 5.2 and 11.6% of CO and NMHC emissions, respectively.

Study of advanced fuel system concepts for commercial aircraft

NASA Technical Reports Server (NTRS)

Coffinberry, G. A.

1985-01-01

An analytical study was performed in order to assess relative performance and economic factors involved with alternative advanced fuel systems for future commercial aircraft operating with broadened property fuels. The DC-10-30 wide-body tri-jet aircraft and the CF6-8OX engine were used as a baseline design for the study. Three advanced systems were considered and were specifically aimed at addressing freezing point, thermal stability and lubricity fuel properties. Actual DC-10-30 routes and flight profiles were simulated by computer modeling and resulted in prediction of aircraft and engine fuel system temperatures during a nominal flight and during statistical one-day-per-year cold and hot flights. Emergency conditions were also evaluated. Fuel consumption and weight and power extraction results were obtained. An economic analysis was performed for new aircraft and systems. Advanced system means for fuel tank heating included fuel recirculation loops using engine lube heat and generator heat. Environmental control system bleed air heat was used for tank heating in a water recirculation loop. The results showed that fundamentally all of the three advanced systems are feasible but vary in their degree of compatibility with broadened-property fuel.

A hazard control system for robot manipulators

NASA Technical Reports Server (NTRS)

Carter, Ruth Chiang; Rad, Adrian

1991-01-01

A robot for space applications will be required to complete a variety of tasks in an uncertain, harsh environment. This fact presents unusual and highly difficult challenges to ensuring the safety of astronauts and keeping the equipment they depend on from becoming damaged. The systematic approach being taken to control hazards that could result from introducing robotics technology in the space environment is described. First, system safety management and engineering principles, techniques, and requirements are discussed as they relate to Shuttle payload design and operation in general. The concepts of hazard, hazard category, and hazard control, as defined by the Shuttle payload safety requirements, is explained. Next, it is shown how these general safety management and engineering principles are being implemented on an actual project. An example is presented of a hazard control system for controlling one of the hazards identified for the Development Test Flight (DTF-1) of NASA's Flight Telerobotic Servicer, a teleoperated space robot. How these schemes can be applied to terrestrial robots is discussed as well. The same software monitoring and control approach will insure the safe operation of a slave manipulator under teleoperated or autonomous control in undersea, nuclear, or manufacturing applications where the manipulator is working in the vicinity of humans or critical hardware.

Research on transient thermal process of a friction brake during repetitive cycles of operation

NASA Astrophysics Data System (ADS)

Slavchev, Yanko; Dimitrov, Lubomir; Dimitrov, Yavor

2017-12-01

Simplified models are used in the classical engineering analyses of the friction brake heating temperature during repetitive cycles of operation to determine basically the maximum and minimum brake temperatures. The objective of the present work is to broaden and complement the possibilities for research through a model that is based on the classical scheme of the Newton's law of cooling and improves the studies by adding a disturbance function for a corresponding braking process. A general case of braking in non-periodic repetitive mode is considered, for which a piecewise function is defined to apply pulse thermal loads to the system. Cases with rectangular and triangular waveforms are presented. Periodic repetitive braking process is also studied using a periodic rectangular waveform until a steady thermal state is achieved. Different numerical methods such as the Euler's method, the classical fourth order Runge-Kutta (RK4) and the Runge-Kutta-Fehlberg 4-5 (RKF45) are used to solve the non-linear differential equation of the model. The constructed model allows during pre-engineering calculations to be determined effectively the time for reaching the steady thermal state of the brake, to be simulated actual braking modes in vehicles and material handling machines, and to be accounted for the thermal impact when performing fatigue calculations.

Phase of Photothermal Emission Analysis as a Diagnostic Tool for Thermal Barrier Coatings on Serviceable Engine Components

NASA Astrophysics Data System (ADS)

Kakuda, Tyler

Power generation and aircraft companies are continuously improving the efficiency of gas turbines to meet economic and environmental goals. The trend towards higher efficiency has been achieved in part by raising the operating temperature of engines. At elevated temperatures, engine components are subject to many forms of degradation including oxidation, creep deformation and thermal cycle fatigue. To minimize these harmful effects, ceramic thermal barrier coatings (TBCs) are routinely used to insulate metal components from excessive heat loads. Efforts to make realistic performance assessments of current and candidate coating materials has led to a diverse battery of creative measurement techniques. While it is unrealistic to envision a single measurement that would provide all conceivable information about the TBC, it is arguable that the capability for the single most important measurement is still lacking. A quantitative and nondestructive measurement of the thermal protection offered by a coating is not currently among the measurements one can employ on a serviceable engine part (or even many experimental specimens). In this contribution, phase of photothermal emission analysis (PopTea) is presented as a viable thermal property measurement for serviceable engine components. As it will be shown, PopTea has the versatility to make measurements on gas turbine parts in situ, with the goal of monitoring TBCs over the lifetime of the engine. The main challenges toward this goal are dealing with changes that occur to the TBC during service. Several of the main degradations seen on engine equipment include: aging, surface contamination and infiltration of foreign deposits. Measuring coatings under these conditions, is the impetus of this work. Furthermore, it is demonstrated that PopTea can be used on real engine equipment with measurements made on an actual turbine blade.

Idle speed and fuel vapor recovery control system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Orzel, D.V.

1993-06-01

A method for controlling idling speed of an engine via bypass throttle connected in parallel to a primary engine throttle and for controlling purge flow through a vapor recovery system into an air/fuel intake of the engine is described, comprising the steps of: positioning the bypass throttle to decrease any difference between a desired engine idle speed and actual engine idle speed; and decreasing the purge flow when said bypass throttle position is less than a preselected fraction of a maximum bypass throttle position.

Computer Simulation Of An In-Process Surface Finish Sensor.

NASA Astrophysics Data System (ADS)

Rakels, Jan H.

1987-01-01

It is generally accepted, that optical methods are the most promising for the in-process measurement of surface finish. These methods have the advantages of being non-contacting and fast data acquisition. Furthermore, these optical instruments can be easily retrofitted on existing machine-tools. In the Micro-Engineering Centre at the University of Warwick, an optical sensor has been developed which can measure the rms roughness, slope and wavelength of turned and precision ground surfaces during machining. The operation of this device is based upon the Kirchhoff-Fresnel diffraction integral. Application of this theory to ideal turned and ground surfaces is straightforward, and indeed the calculated diffraction patterns are in close agreement with patterns produced by an actual optical instrument. Since it is mathematically difficult to introduce real machine-tool behaviour into the diffraction integral, a computer program has been devised, which simulates the operation of the optical sensor. The program produces a diffraction pattern as a graphical output. Comparison between computer generated and actual diffraction patterns of the same surfaces show a high correlation. The main aim of this program is to construct an atlas, which maps known machine-tool errors versus optical diffraction patterns. This atlas can then be used for machine-tool condition diagnostics. It has been found that optical monitoring is very sensitive to minor defects. Therefore machine-tool detoriation can be detected before it is detrimental.

Team Problem Solving Strategies with a Survey of These Methods Used by Faculty Members in Engineering Technology

ERIC Educational Resources Information Center

Marcus, Michael L.; Winters, Dixie L.

2004-01-01

Students from science, engineering, and technology programs should be able to work together as members of project teams to find solutions to technical problems. The exercise in this paper describes the methods actually used by a project team from a Biomedical Instrumentation Corporation in which scientists, technicians, and engineers from various…

Thin film temperature sensors, phase 3. [for engine-test evaluation

NASA Technical Reports Server (NTRS)

Grant, H. P.; Przybyszewski, J. S.; Claing, R. G.; Anderson, W. L.

1982-01-01

A thin film thermocouple system installation suitable for engine test evaluation was designed, and an engine test plan was prepared. Film adherence, durability, accuracy, and drift characteristics were improved. Film thickness was increased to 14 microns, and drift was reduced to less than 0.02 percent of Fahrenheit temperature per hour on actual turbine blades at 1255 K.

Theseus Engine Being Unloaded

NASA Technical Reports Server (NTRS)

1996-01-01

Crew members are seen here unloading an engine of the Theseus prototype research aircraft at NASA's Dryden Flight Research Center, Edwards, California, in May of 1996. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements. Dryden's Project Manager was John Del Frate.

Protection Relaying Scheme Based on Fault Reactance Operation Type

NASA Astrophysics Data System (ADS)

Tsuji, Kouichi

The theories of operation of existing relays are roughly divided into two types: one is the current differential types based on Kirchhoff's first law and the other is impedance types based on second law. We can apply the Kirchhoff's laws to strictly formulate fault phenomena, so the circuit equations are represented non linear simultaneous equations with variables fault point k and fault resistance Rf. This method has next two defect. 1) heavy computational burden for the iterative calculation on N-R method, 2) relay operator can not easily understand principle of numerical matrix operation. The new protection relay principles we proposed this paper focuses on the fact that the reactance component on fault point is almost zero. Two reactance Xf(S), Xf(R) on branch both ends are calculated by operation of solving linear equations. If signs of Xf(S) and Xf(R) are not same, it can be judged that the fault point exist in the branch. This reactance Xf corresponds to difference of branch reactance between actual fault point and imaginaly fault point. And so relay engineer can to understand fault location by concept of “distance". The simulation results using this new method indicates the highly precise estimation of fault locations compared with the inspected fault locations on operating transmission lines.

Optical Design and Engineering: Lessons Learned

NASA Technical Reports Server (NTRS)

Mouroulis, Pantazis

2005-01-01

This paper contains some recommendations for the optics curricula that seek to serve students intent on a career in optical engineering, as well as suggestions for the young professional embarking on such a career. It also illustrates the suggestions with some examples of actual optical systems.

49 CFR 238.203 - Static end strength.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., sufficient to describe the actual construction of the equipment; (iii) Engineering analysis sufficient to..., engineering analysis, and risk mitigation measures described in this paragraph, demonstrating that the use of... the Federal Docket Management System and posted on its web site at http://www.regulations.gov. (h...

49 CFR 238.203 - Static end strength.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., sufficient to describe the actual construction of the equipment; (iii) Engineering analysis sufficient to..., engineering analysis, and risk mitigation measures described in this paragraph, demonstrating that the use of... the Federal Docket Management System and posted on its web site at http://www.regulations.gov. (h...

Enhancing Individual Employability: The Perspective of Engineering Graduates

ERIC Educational Resources Information Center

Nilsson, Staffan

2010-01-01

Purpose: Employability includes the ability to find employment and remain employed. Employability includes both hard and soft skills, including formal and actual competence, interpersonal skills, and personal characteristics. This paper aims to focus on illuminating perceptions engineering graduates have regarding employability. More specifically,…

Professional Skills Needed by Our Graduates

ERIC Educational Resources Information Center

Woods, Donald R.; Briedis, Daina; Perna, Angelo

2013-01-01

Accreditation agencies have outlined professional skills that should be possessed by engineering graduates. The question this paper addresses is "What professional skills do our recent graduates actually use and value as being important?" Young engineering professionals, as well as professionals in many different professions, were asked…

Integrating Thermal Tools Into the Mechanical Design Process

NASA Technical Reports Server (NTRS)

Tsuyuki, Glenn T.; Siebes, Georg; Novak, Keith S.; Kinsella, Gary M.

1999-01-01

The intent of mechanical design is to deliver a hardware product that meets or exceeds customer expectations, while reducing cycle time and cost. To this end, an integrated mechanical design process enables the idea of parallel development (concurrent engineering). This represents a shift from the traditional mechanical design process. With such a concurrent process, there are significant issues that have to be identified and addressed before re-engineering the mechanical design process to facilitate concurrent engineering. These issues also assist in the integration and re-engineering of the thermal design sub-process since it resides within the entire mechanical design process. With these issues in mind, a thermal design sub-process can be re-defined in a manner that has a higher probability of acceptance, thus enabling an integrated mechanical design process. However, the actual implementation is not always problem-free. Experience in applying the thermal design sub-process to actual situations provides the evidence for improvement, but more importantly, for judging the viability and feasibility of the sub-process.

14 CFR 27.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Turbine engine operating characteristics....939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be... limitations of the rotorcraft and of the engine. (b) The turbine engine air inlet system may not, as a result...

14 CFR 27.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Turbine engine operating characteristics....939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be... limitations of the rotorcraft and of the engine. (b) The turbine engine air inlet system may not, as a result...

14 CFR 27.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Turbine engine operating characteristics....939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be... limitations of the rotorcraft and of the engine. (b) The turbine engine air inlet system may not, as a result...

14 CFR 29.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Turbine engine operating characteristics....939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be... limitations of the rotorcraft and of the engine. (b) The turbine engine air inlet system may not, as a result...

14 CFR 29.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Turbine engine operating characteristics....939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be... limitations of the rotorcraft and of the engine. (b) The turbine engine air inlet system may not, as a result...

14 CFR 29.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Turbine engine operating characteristics....939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be... limitations of the rotorcraft and of the engine. (b) The turbine engine air inlet system may not, as a result...

14 CFR 29.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Turbine engine operating characteristics....939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be... limitations of the rotorcraft and of the engine. (b) The turbine engine air inlet system may not, as a result...

14 CFR 27.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Turbine engine operating characteristics....939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be... limitations of the rotorcraft and of the engine. (b) The turbine engine air inlet system may not, as a result...

14 CFR 27.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Turbine engine operating characteristics....939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be... limitations of the rotorcraft and of the engine. (b) The turbine engine air inlet system may not, as a result...

14 CFR 29.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Turbine engine operating characteristics....939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be... limitations of the rotorcraft and of the engine. (b) The turbine engine air inlet system may not, as a result...

Surface Temperature Measurements from a Stator Vane Doublet in a Turbine Engine Afterburner Flame using Ultra-Bright Cr-Doped GdAlO3 Thermographic Phosphor

NASA Technical Reports Server (NTRS)

Eldridge, Jeffrey I.; Jenkins, Thomas P.; Allison, Stephen W.; Wolfe, Douglas E.; Howard, Robert P.

2013-01-01

Luminescence-based surface temperature measurements from an ultra-bright Cr-doped GdAlO3 perovskite (GAP:Cr) coating were successfully conducted on an air-film-cooled stator vane doublet exposed to the afterburner flame of a J85 test engine at University of Tennessee Space Institute (UTSI). The objective of the testing at UTSI was to demonstrate that reliable thermal barrier coating (TBC) surface temperatures based on luminescence decay of a thermographic phosphor could be obtained from the surface of an actual engine component in an aggressive afterburner flame environment and to address the challenges of a highly radiant background and high velocity gases. A high-pressure turbine vane doublet from a Honeywell TECH7000 turbine engine was coated with a standard electron-beam physical vapor deposited (EB-PVD) 200-m-thick TBC composed of yttria-stabilized zirconia (YSZ) onto which a 25-m-thick GAP:Cr thermographic phosphor layer was deposited by EB-PVD. The ultra-bright broadband luminescence from the GAP:Cr thermographic phosphor is shown to offer the advantage of over an order-of-magnitude greater emission intensity compared to rare-earth-doped phosphors in the engine test environment. This higher emission intensity was shown to be very desirable for overcoming the necessarily restricted probe light collection solid angle and for achieving high signal-to-background levels. Luminescence-decay-based surface temperature measurements varied from 500 to over 1000C depending on engine operating conditions and level of air film cooling.

Thermal Hardware for the Thermal Analyst

NASA Technical Reports Server (NTRS)

Steinfeld, David

2015-01-01

The presentation will be given at the 26th Annual Thermal Fluids Analysis Workshop (TFAWS 2015) hosted by the Goddard Space Flight Center (GSFC) Thermal Engineering Branch (Code 545). NCTS 21070-1. Most Thermal analysts do not have a good background into the hardware which thermally controls the spacecraft they design. SINDA and Thermal Desktop models are nice, but knowing how this applies to the actual thermal hardware (heaters, thermostats, thermistors, MLI blanketing, optical coatings, etc...) is just as important. The course will delve into the thermal hardware and their application techniques on actual spacecraft. Knowledge of how thermal hardware is used and applied will make a thermal analyst a better engineer.

Operation of a sampling train for the analysis of environmental species in coal gasification gas-phase process streams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pochan, M.J.; Massey, M.J.

1979-02-01

This report discusses the results of actual raw product gas sampling efforts and includes: Rationale for raw product gas sampling efforts; design and operation of the CMU gas sampling train; development and analysis of a sampling train data base; and conclusions and future application of results. The results of sampling activities at the CO/sub 2/-Acceptor and Hygas pilot plants proved that: The CMU gas sampling train is a valid instrument for characterization of environmental parameters in coal gasification gas-phase process streams; depending on the particular process configuration, the CMU gas sampling train can reduce gasifier effluent characterization activity to amore » single location in the raw product gas line; and in contrast to the slower operation of the EPA SASS Train, CMU's gas sampling train can collect representative effluent data at a rapid rate (approx. 2 points per hour) consistent with the rate of change of process variables, and thus function as a tool for process engineering-oriented analysis of environmental characteristics.« less

Emission factors for gaseous and particulate pollutants from offshore diesel engine vessels in China

NASA Astrophysics Data System (ADS)

Zhang, Fan; Chen, Yingjun; Tian, Chongguo; Lou, Diming; Li, Jun; Zhang, Gan; Matthias, Volker

2016-05-01

Shipping emissions have significant influence on atmospheric environment as well as human health, especially in coastal areas and the harbour districts. However, the contribution of shipping emissions on the environment in China still need to be clarified especially based on measurement data, with the large number ownership of vessels and the rapid developments of ports, international trade and shipbuilding industry. Pollutants in the gaseous phase (carbon monoxide, sulfur dioxide, nitrogen oxides, total volatile organic compounds) and particle phase (particulate matter, organic carbon, elemental carbon, sulfates, nitrate, ammonia, metals) in the exhaust from three different diesel-engine-powered offshore vessels in China (350, 600 and 1600 kW) were measured in this study. Concentrations, fuel-based and power-based emission factors for various operating modes as well as the impact of engine speed on emissions were determined. Observed concentrations and emission factors for carbon monoxide, nitrogen oxides, total volatile organic compounds, and particulate matter were higher for the low-engine-power vessel (HH) than for the two higher-engine-power vessels (XYH and DFH); for instance, HH had NOx EF (emission factor) of 25.8 g kWh-1 compared to 7.14 and 6.97 g kWh-1 of DFH, and XYH, and PM EF of 2.09 g kWh-1 compared to 0.14 and 0.04 g kWh-1 of DFH, and XYH. Average emission factors for all pollutants except sulfur dioxide in the low-engine-power engineering vessel (HH) were significantly higher than that of the previous studies (such as 30.2 g kg-1 fuel of CO EF compared to 2.17 to 19.5 g kg-1 fuel in previous studies, 115 g kg-1 fuel of NOx EF compared to 22.3 to 87 g kg-1 fuel in previous studies and 9.40 g kg-1 fuel of PM EF compared to 1.2 to 7.6 g kg-1 fuel in previous studies), while for the two higher-engine-power vessels (DFH and XYH), most of the average emission factors for pollutants were comparable to the results of the previous studies, engine type was one of the most important influence factors for the differences. Emission factors for all three vessels were significantly different during different operating modes. Organic carbon and elemental carbon were the main components of particulate matter, while water-soluble ions and elements were present in trace amounts. The test inland ships and some test offshore vessels in China always had higher EFs for CO, NOx, and PM than previous studies. Besides, due to the significant influence of engine type on shipping emissions and that no accurate local EFs could be used in inventory calculation, much more measurement data for different vessels in China are still in urgent need. Best-fit engine speeds during actual operation should be based on both emission factors and economic costs.

Bell P-39 in the Icing Research Tunnel

NASA Image and Video Library

1944-11-21

A Bell P-39 Airacobra in the NACA Aircraft Engine Research Laboratory’s Icing Research Tunnel for a propeller deicing study. The tunnel, which began operation in June 1944, was built to study the formation of ice on aircraft surfaces and methods of preventing or eradicating that ice. Ice buildup adds extra weight to aircraft, effects aerodynamics, and sometimes blocks airflow through engines. NACA design engineers added the Icing Research Tunnel to the new AERL’s original layout to take advantage of the massive refrigeration system being constructed for the Altitude Wind Tunnel. The Icing Research Tunnel is a closed-loop atmospheric wind tunnel with a 6- by 9-foot test section. The tunnel can produce speeds up to 300 miles per hour and temperatures from about 30 to –45⁰ F. During World War II AERL researchers analyzed different ice protection systems for propeller, engine inlets, antennae, and wings in the icing tunnel. The P-39 was a vital low-altitude pursuit aircraft of the US during the war. NACA investigators investigated several methods of preventing ice buildup on the P-39’s propeller, including the use of internal and external electrical heaters, alcohol, and hot gases. They found that continual heating of the blades expended more energy than the aircraft could supply, so studies focused on intermittent heating. The results of the wind tunnel investigations were then compared to actual flight tests on aircraft.

Vultee YA–31C Vengeance at the NACA

NASA Image and Video Library

1945-03-21

A Bell P-39 Airacobra in the NACA Aircraft Engine Research Laboratory’s Icing Research Tunnel for a propeller deicing study. The tunnel, which began operation in June 1944, was built to study the formation of ice on aircraft surfaces and methods of preventing or eradicating that ice. Ice buildup adds extra weight to aircraft, effects aerodynamics, and sometimes blocks airflow through engines. NACA design engineers added the Icing Research Tunnel to the new AERL’s original layout to take advantage of the massive refrigeration system being constructed for the Altitude Wind Tunnel. The Icing Research Tunnel is a closed-loop atmospheric wind tunnel with a 6- by 9-foot test section. The tunnel can produce speeds up to 300 miles per hour and temperatures from about 30 to -45⁰ F. During World War II AERL researchers analyzed different ice protection systems for propeller, engine inlets, antennae, and wings in the icing tunnel. The P-39 was a vital low-altitude pursuit aircraft of the US during the war. NACA investigators investigated several methods of preventing ice buildup on the P-39’s propeller, including the use of internal and external electrical heaters, alcohol, and hot gases. They found that continual heating of the blades expended more energy than the aircraft could supply, so studies focused on intermittent heating. The results of the wind tunnel investigations were then compared to actual flight tests on aircraft.

Laser Absorption Measurements of Equivalence Ratios Studied Along With Their Coupling to Pressure Fluctuations in Lean Premixed Prevaporized (LPP) Combustion

NASA Technical Reports Server (NTRS)

Nguyen, Quang-Viet

2001-01-01

Concerns about damaging the Earth's ozone layer as a result of high levels of nitrogen oxides (known collectively as NOx) from high-altitude, high-speed aircraft have prompted the study of lean premixed prevaporized (LPP) combustion in aircraft engines. LPP combustion reduces NOx emissions principally by reducing the peak flame temperatures inside an engine. Recent advances in LPP technologies have realized exceptional reductions in pollutant emissions (single-digit ppm NOx for example). However, LPP combustion also presents major challenges: combustion instability and dynamic coupling effects between fluctuations in heat-release rate, dynamic pressure, and fuel pressure. These challenges are formidable and can literally shake an engine apart if uncontrolled. To better understand this phenomenon so that it can be controlled, we obtained real-time laser absorption measurements of the fuel vapor concentration (and equivalence ratio) simultaneously with the dynamic pressure, flame luminosity, and time-averaged gaseous emissions measurements in a research-type jet-A-fueled LPP combustor. The measurements were obtained in NASA Glenn Research Center's CE-5B optically accessible flame tube facility. The CE-5B facility provides inlet air temperatures and pressures similar to the actual operating conditions of real aircraft engines. The laser absorption measurements were performed using an infrared 3.39 micron HeNe laser in conjunction with a visible HeNe laser for liquid droplet scattering compensation.

Software engineering technology transfer: Understanding the process

NASA Technical Reports Server (NTRS)

Zelkowitz, Marvin V.

1993-01-01

Technology transfer is of crucial concern to both government and industry today. In this report, the mechanisms developed by NASA to transfer technology are explored and the actual mechanisms used to transfer software development technologies are investigated. Time, cost, and effectiveness of software engineering technology transfer is reported.

47 CFR 27.1180 - The cost-sharing formula.

Code of Federal Regulations, 2010 CFR

2010-10-01

...); towers and/or modifications; back-up power equipment; monitoring or control equipment; engineering costs (design/path survey); installation; systems testing; FCC filing costs; site acquisition and civil works... as equipment and engineering expenses. There is no cap on the actual costs of relocation. (c) An AWS...

HI-TIE: The University, the High School, and Engineering

ERIC Educational Resources Information Center

Ward, Robert C.; Maxwell, Lee M.

1975-01-01

Describes four years experience at Colorado State University with courses introducing high school students to engineering, including a Fortran IV computer programming course in which tapings of actual campus classroom sessions, supplemented with homework assignments, class roles, quizzes, and examinations were used. Benefits of the transitional…

Fuel cell stack monitoring and system control

DOEpatents

Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

2005-01-25

A control method for monitoring a fuel cell stack in a fuel cell system in which the actual voltage and actual current from the fuel cell stack are monitored. A preestablished relationship between voltage and current over the operating range of the fuel cell is established. A variance value between the actual measured voltage and the expected voltage magnitude for a given actual measured current is calculated and compared with a predetermined allowable variance. An output is generated if the calculated variance value exceeds the predetermined variance. The predetermined voltage-current for the fuel cell is symbolized as a polarization curve at given operating conditions of the fuel cell. Other polarization curves may be generated and used for fuel cell stack monitoring based on different operating pressures, temperatures, hydrogen quantities.

Performance of winter rape (Brassica napus) based fuel mixtures in diesel engines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wagner, G.L.; Peterson, C.L.

1982-01-01

Winter rape is well adapted to the Palouse region of Northern Idaho and Eastern Washington. Nearly all of the current US production is grown in this region. Yields of 2200 to 2700 kg/ha with 45 percent oil content are common. Even though present production only 2000 to 2500 ha per year, the long history of production and good yields of oil make winter rape the best potential fuel vegetable oil crop for the region. Winter rape oil is more viscous than sunflower oil (50 cSt at 40/sup 0/C for winter rape and 35 cSt at 40/sup 0/C for sunflower oil)more » and about 17 times more viscous than diesel. The viscosity of the pure oil has been found too high for operation in typical diesel injector systems. Mixtures and/or additives are essential if the oil is to be a satisfactory fuel. Conversely, the fatty acid composition of witer rape oils is such that it is potentially a more favorable fuel because of reduced rates of oxidation and thermal polymerization. This paper will report on results of short and long term engine tests using winter rape, diesel, and commercial additives as the components. Selection of mixtures for long term screening tests was based on laboratory studies which included high temperature oxidation studies and temperature-viscosity data. Fuel temperature has been monitored at the outlet of the injector nozzle on operating engines so that viscosity comparisons at the actual injector temperature can be made. 1 figure, 3 tables.« less

Analysis of economic and environmental benefits of a new heat pump air conditioning system with a heat recovery device

NASA Astrophysics Data System (ADS)

Li, lingxue

2017-08-01

The paper designs a new wind-water cooling and heating water conditioner system, connects cooling tower with heat recovery device, which uses cooling water to completely remove the heat that does not need heat recollection, in order to ensure that the system can work efficiently with higher performance coefficient. After the test actual engineering operation, the system’s maximum cooling coefficient of performance can reach 3.5. Its maximum comprehensive coefficient of performance can reach 6.5. After the analysis of its economic and environmental, we conclude that the new system can save 89822 kw per year. It reflects energy-saving and environmental benefits of the cold and hot water air conditioning system.

Introduction to the Space Transportation System. [space shuttle cost effectiveness

NASA Technical Reports Server (NTRS)

Wilson, R. G.

1973-01-01

A new space transportation concept which is consistent with the need for more cost effective space operations has been developed. The major element of the Space Transportation System (STS) is the Space Shuttle. The rest of the system consists of a propulsive stage which can be carried within the space shuttle to obtain higher energy orbits. The final form of this propulsion stage will be called the Space Tug. A third important element, which is not actually a part of the STS since it has no propulsive capacity, is the Space Laboratory. The major element of the Space Shuttle is an aircraft-like orbiter which contains the crew, the cargo, and the liquid rocket engines in the rear.

Superfund record of decision (EPA region 10): Idaho National Engineering Lab, (USDOE) Operable Unit 26 (Stationary Low-Power Reactor-1 and Boiling Water Reactor Experiment-I Burial Grounds), Idaho Falls, ID, December 1, 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-03-01

This document presents the selected remedial action for the Stationary Low-Power Reactor-1 (SL-1) burial ground, the Boiling Water Reactor Experiment-I (BORAX-I) burial ground, and 10 no action sites in Waste Area Group 5. Actual or threatened releases of hazardous substances from the SL-1 and BORAX-I burial grounds, if not addressed by implementing the response action selected in this Record of Decision, may present a current or potential threat to public health, welfare, or the environment. The 10 no action sites do not present a threat to human health or the environment.

MAP Fault Localization Based on Wide Area Synchronous Phasor Measurement Information

NASA Astrophysics Data System (ADS)

Zhang, Yagang; Wang, Zengping

2015-02-01

In the research of complicated electrical engineering, the emergence of phasor measurement units (PMU) is a landmark event. The establishment and application of wide area measurement system (WAMS) in power system has made widespread and profound influence on the safe and stable operation of complicated power system. In this paper, taking full advantage of wide area synchronous phasor measurement information provided by PMUs, we have carried out precise fault localization based on the principles of maximum posteriori probability (MAP). Large numbers of simulation experiments have confirmed that the results of MAP fault localization are accurate and reliable. Even if there are interferences from white Gaussian stochastic noise, the results from MAP classification are also identical to the actual real situation.

An Overview of the Microgravity Science Glovebox (MSG) Facility and the Research Performed in the MSG on the International Space Station (ISS)

NASA Technical Reports Server (NTRS)

Jordan, Lee P.

2013-01-01

The Microgravity Science Glovebox (MSG) is a rack facility aboard the International Space Station (ISS) designed for investigation handling. The MSG was built by the European Space Agency (ESA) which also provides sustaining engineering support for the facility. The MSG has been operating on the ISS since July 2002 and is currently located in the US Laboratory Module. The unique design of the facility allows it to accommodate science and technology investigations in a "workbench" type environment. The facility has an enclosed working volume that is held at a negative pressure with respect to the crew living area. This allows the facility to provide two levels of containment for small parts, particulates, fluids, and gases. This containment approach protects the crew from possible hazardous operations that take place inside the MSG work volume. Research investigations operating inside the MSG are provided a large 255 liter enclosed work space, 1000 watts of dc power via a versatile supply interface (120, 28, +/- 12, and 5 Vdc), 1000 watts of cooling capability, video and data recording and real time downlink, ground commanding capabilities, access to ISS Vacuum Exhaust and Vacuum Resource Systems, and gaseous nitrogen supply. These capabilities make the MSG one of the most utilized facilities on ISS. The MSG has been used for over 14500 hours of scientific payload operations. MSG investigations involve research in cryogenic fluid management, fluid physics, spacecraft fire safety, materials science, combustion, plant growth, and life support technology. The MSG facility is operated by the Payloads Operations Integration Center at Marshall Space flight Center. Payloads may also operate remotely from different telescience centers located in the United States and Europe. The investigative Payload Integration Manager (iPIM) is the focal to assist organizations that have payloads operating in the MSG facility. NASA provides an MSG engineering unit for payload developers to verify that their hardware is operating properly before actual operation on the ISS. This paper will provide an overview of the MSG facility, a synopsis of the research that has already been accomplished in the MSG, and an overview of video and biological upgrades.

Method and apparatus for effecting light-off of a catalytic converter in a hybrid powertrain system

DOEpatents

Roos, Bryan Nathaniel; Spohn, Brian L

2013-07-02

A powertrain system includes a hybrid transmission and an internal combustion engine coupled to an exhaust aftertreatment device. A method for operating the powertrain system includes operating the hybrid transmission to generate tractive torque responsive to an operator torque request with the internal combustion engine in an engine-off state so long as the tractive torque is less than a threshold. The internal combustion engine is operated in an engine-on state at preferred operating conditions to effect light-off of the exhaust aftertreatment device and the hybrid transmission is coincidentally operated to generate tractive torque responsive to the operator torque request when the operator torque request exceeds the threshold. The internal combustion engine is then operated in the engine-on state to generate tractive torque responsive to the operator torque request.

Path planning during combustion mode switch

DOEpatents

Jiang, Li; Ravi, Nikhil

2015-12-29

Systems and methods are provided for transitioning between a first combustion mode and a second combustion mode in an internal combustion engine. A current operating point of the engine is identified and a target operating point for the internal combustion engine in the second combustion mode is also determined. A predefined optimized transition operating point is selected from memory. While operating in the first combustion mode, one or more engine actuator settings are adjusted to cause the operating point of the internal combustion engine to approach the selected optimized transition operating point. When the engine is operating at the selected optimized transition operating point, the combustion mode is switched from the first combustion mode to the second combustion mode. While operating in the second combustion mode, one or more engine actuator settings are adjusted to cause the operating point of the internal combustion to approach the target operating point.

Defining a region of optimization based on engine usage data

DOEpatents

Jiang, Li; Lee, Donghoon; Yilmaz, Hakan; Stefanopoulou, Anna

2015-08-04

Methods and systems for engine control optimization are provided. One or more operating conditions of a vehicle engine are detected. A value for each of a plurality of engine control parameters is determined based on the detected one or more operating conditions of the vehicle engine. A range of the most commonly detected operating conditions of the vehicle engine is identified and a region of optimization is defined based on the range of the most commonly detected operating conditions of the vehicle engine. The engine control optimization routine is initiated when the one or more operating conditions of the vehicle engine are within the defined region of optimization.

Intelligent Launch and Range Operations Virtual Test Bed (ILRO-VTB)

NASA Technical Reports Server (NTRS)

Bardina, Jorge; Rajkumar, T.

2003-01-01

Intelligent Launch and Range Operations Virtual Test Bed (ILRO-VTB) is a real-time web-based command and control, communication, and intelligent simulation environment of ground-vehicle, launch and range operation activities. ILRO-VTB consists of a variety of simulation models combined with commercial and indigenous software developments (NASA Ames). It creates a hybrid software/hardware environment suitable for testing various integrated control system components of launch and range. The dynamic interactions of the integrated simulated control systems are not well understood. Insight into such systems can only be achieved through simulation/emulation. For that reason, NASA has established a VTB where we can learn the actual control and dynamics of designs for future space programs, including testing and performance evaluation. The current implementation of the VTB simulates the operations of a sub-orbital vehicle of mission, control, ground-vehicle engineering, launch and range operations. The present development of the test bed simulates the operations of Space Shuttle Vehicle (SSV) at NASA Kennedy Space Center. The test bed supports a wide variety of shuttle missions with ancillary modeling capabilities like weather forecasting, lightning tracker, toxic gas dispersion model, debris dispersion model, telemetry, trajectory modeling, ground operations, payload models and etc. To achieve the simulations, all models are linked using Common Object Request Broker Architecture (CORBA). The test bed provides opportunities for government, universities, researchers and industries to do a real time of shuttle launch in cyber space.

Intelligent launch and range operations virtual testbed (ILRO-VTB)

NASA Astrophysics Data System (ADS)

Bardina, Jorge; Rajkumar, Thirumalainambi

2003-09-01

Intelligent Launch and Range Operations Virtual Test Bed (ILRO-VTB) is a real-time web-based command and control, communication, and intelligent simulation environment of ground-vehicle, launch and range operation activities. ILRO-VTB consists of a variety of simulation models combined with commercial and indigenous software developments (NASA Ames). It creates a hybrid software/hardware environment suitable for testing various integrated control system components of launch and range. The dynamic interactions of the integrated simulated control systems are not well understood. Insight into such systems can only be achieved through simulation/emulation. For that reason, NASA has established a VTB where we can learn the actual control and dynamics of designs for future space programs, including testing and performance evaluation. The current implementation of the VTB simulates the operations of a sub-orbital vehicle of mission, control, ground-vehicle engineering, launch and range operations. The present development of the test bed simulates the operations of Space Shuttle Vehicle (SSV) at NASA Kennedy Space Center. The test bed supports a wide variety of shuttle missions with ancillary modeling capabilities like weather forecasting, lightning tracker, toxic gas dispersion model, debris dispersion model, telemetry, trajectory modeling, ground operations, payload models and etc. To achieve the simulations, all models are linked using Common Object Request Broker Architecture (CORBA). The test bed provides opportunities for government, universities, researchers and industries to do a real time of shuttle launch in cyber space.

Pedagogical Evaluation of Remote Laboratories in eMerge Project

ERIC Educational Resources Information Center

Lang, Daniela; Mengelkamp, Christoph; Jaeger, Reinhold S.; Geoffroy, Didier; Billaud, Michel; Zimmer, Thomas

2007-01-01

This study investigates opportunities for conducting electrical engineering experiments via the Internet rather than in an actual laboratory. Eighty-four French students of electrical engineering (semester 1, 2004) at Bordeaux University 1 participated in practical courses. Half of the students performed experiments in a laboratory while the other…

24 CFR 905.314 - Cost and other limitations.

Code of Federal Regulations, 2014 CFR

2014-04-01

... excluding any costs related to lead-based paint or asbestos testing, in-house architectural and engineering... lead-based paint or asbestos testing, in-house Architectural and Engineering work, or other special... completion of the project, the actual project cost is determined based upon the amount of public housing...

40 CFR 90.706 - Engine sample selection.

Code of Federal Regulations, 2010 CFR

2010-07-01

... = emission test result for an individual engine. x = mean of emission test results of the actual sample. FEL... test with the last test result from the previous model year and then calculate the required sample size.... Test results used to calculate the variables in the following Sample Size Equation must be final...

Collaborative Approach in Software Engineering Education: An Interdisciplinary Case

ERIC Educational Resources Information Center

Vicente, Aileen Joan; Tan, Tiffany Adelaine; Yu, Alvin Ray

2018-01-01

Aim/Purpose: This study was aimed at enhancing students' learning of software engineering methods. A collaboration between the Computer Science, Business Management, and Product Design programs was formed to work on actual projects with real clients. This interdisciplinary form of collaboration simulates the realities of a diverse Software…

Actual and estimated costs of disposable materials used during surgical procedures.

PubMed

Toyabe, Shin-Ichi; Cao, Pengyu; Kurashima, Sachiko; Nakayama, Yukiko; Ishii, Yuko; Hosoyama, Noriko; Akazawa, Kouhei

2005-07-01

It is difficult to estimate precisely the costs of disposable materials used during surgical operations. To evaluate the actual costs of disposable materials, we calculated the actual costs of disposable materials used in 59 operations by taking account of costs of all disposable materials used for each operation. The costs of the disposable materials varied significantly from operation to operation (US$ 38-4230 per operation), and the median [25-percentile and 75-percentile] of the sum total of disposable material costs of a single operation was found to be US$ 686 [205 and 993]. Multiple regression analysis with a stepwise regression method showed that costs of disposable materials significantly correlated only with operation time (p<0.001). Based on the results, we propose a simple method for estimating costs of disposable materials by measuring operation time, and we found that the method gives reliable results. Since costs of disposable materials used during surgical operations are considerable, precise estimation of the costs is essential for hospital cost accounting. Our method should be useful for planning hospital administration strategies.

Software Re-Engineering of the Human Factors Analysis and Classification System - (Maintenance Extension) Using Object Oriented Methods in a Microsoft Environment

DTIC Science & Technology

2001-09-01

replication) -- all from Visual Basic and VBA . In fact, we found that the SQL Server engine actually had a plethora of options, most formidable of...2002, the new SQL Server 2000 database engine, and Microsoft Visual Basic.NET. This thesis describes our use of the Spiral Development Model to...versions of Microsoft products? Specifically, the pending release of Microsoft Office 2002, the new SQL Server 2000 database engine, and Microsoft

Engineering works and the tidal Chesapeake

NASA Technical Reports Server (NTRS)

Hargis, W. J., Jr.

1972-01-01

The tidal tributaries of the ocean and coastal areas of the mid-Atlantic region and the ecological significance of engineering projects are discussed. The effects of engineering works on maritime environments and resources, with the Chesapeake Bay as the area of prime interest are examined. Significant engineering projects, both actual and proposed, are described. The conflict of navigational demands and maintenance of an estuarine environment for commercial and sport fishing and recreation is described. Specific applications of remote sensors for analyzing ecological conditions of the bay are included.

Multispectral scanner system for ERTS: Four band scanner system. Volume 2: Engineering model panoramic pictures and engineering tests

NASA Technical Reports Server (NTRS)

1972-01-01

This document is Volume 2 of three volumes of the Final Report for the four band Multispectral Scanner System (MSS). The results are contained of an analysis of pictures of actual outdoor scenes imaged by the engineering model MSS for spectral response, resolution, noise, and video correction. Also included are the results of engineering tests on the MSS for reflectance and saturation from clouds. Finally, two panoramic pictures of Yosemite National Park are provided.

14 CFR 23.777 - Cockpit controls.

Code of Federal Regulations, 2010 CFR

2010-01-01

...) Identical powerplant controls for each engine must be located to prevent confusion as to the engines they...) operates the left engines(s) and the right control(s) operates the right engine(s). (2) On twin-engine airplanes with front and rear engine locations (tandem), the left powerplant controls must operate the front...

46 CFR 113.35-13 - Mechanical engine order telegraph systems; operation.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Mechanical engine order telegraph systems; operation...) ELECTRICAL ENGINEERING COMMUNICATION AND ALARM SYSTEMS AND EQUIPMENT Engine Order Telegraph Systems § 113.35-13 Mechanical engine order telegraph systems; operation. If more than one transmitter operates a...

46 CFR 113.35-13 - Mechanical engine order telegraph systems; operation.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Mechanical engine order telegraph systems; operation...) ELECTRICAL ENGINEERING COMMUNICATION AND ALARM SYSTEMS AND EQUIPMENT Engine Order Telegraph Systems § 113.35-13 Mechanical engine order telegraph systems; operation. If more than one transmitter operates a...

46 CFR 113.35-13 - Mechanical engine order telegraph systems; operation.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Mechanical engine order telegraph systems; operation...) ELECTRICAL ENGINEERING COMMUNICATION AND ALARM SYSTEMS AND EQUIPMENT Engine Order Telegraph Systems § 113.35-13 Mechanical engine order telegraph systems; operation. If more than one transmitter operates a...

46 CFR 113.35-13 - Mechanical engine order telegraph systems; operation.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Mechanical engine order telegraph systems; operation...) ELECTRICAL ENGINEERING COMMUNICATION AND ALARM SYSTEMS AND EQUIPMENT Engine Order Telegraph Systems § 113.35-13 Mechanical engine order telegraph systems; operation. If more than one transmitter operates a...

Relationships between Actualizing Concrete and Formal Science Teaching Intentions and the Levels of Cognitive Development among Some Prospective Teachers in Nigeria.

ERIC Educational Resources Information Center

Ehindero, Olusola J.

1980-01-01

Determines relationships between prospective secondary school science teachers' (N=60) level of cognitive development (i.e., Piaget's concrete operational or formal operational stage) and success in stating and actualizing teaching intentions. (CS)

Space shuttle main engine computed tomography applications

NASA Technical Reports Server (NTRS)

Sporny, Richard F.

1990-01-01

For the past two years the potential applications of computed tomography to the fabrication and overhaul of the Space Shuttle Main Engine were evaluated. Application tests were performed at various government and manufacturer facilities with equipment produced by four different manufacturers. The hardware scanned varied in size and complexity from a small temperature sensor and turbine blades to an assembled heat exchanger and main injector oxidizer inlet manifold. The evaluation of capabilities included the ability to identify and locate internal flaws, measure the depth of surface cracks, measure wall thickness, compare manifold design contours to actual part contours, perform automatic dimensional inspections, generate 3D computer models of actual parts, and image the relationship of the details in a complex assembly. The capabilities evaluated, with the exception of measuring the depth of surface flaws, demonstrated the existing and potential ability to perform many beneficial Space Shuttle Main Engine applications.

The JSC Engineering Directorate Product Peer Review Process

NASA Technical Reports Server (NTRS)

Jenks, Kenneth C.

2009-01-01

The JSC Engineering Directorate has developed a Product Peer Review process in support of NASA policies for project management and systems engineering. The process complies with the requirements of NPR 7120.5, NPR 7123.1 and NPR 7150.2 and follows the guidance in NASA/SP-2007-6105. This presentation will give an overview of the process followed by a brief demonstration of an actual peer review, with audience participation.

14 CFR 121.179 - Airplanes: Reciprocating engine-powered: En route limitations: All engines operating.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Airplanes: Reciprocating engine-powered: En...: CERTIFICATION AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.179 Airplanes: Reciprocating engine-powered: En route limitations: All...

14 CFR 121.179 - Airplanes: Reciprocating engine-powered: En route limitations: All engines operating.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Airplanes: Reciprocating engine-powered: En...: CERTIFICATION AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.179 Airplanes: Reciprocating engine-powered: En route limitations: All...

14 CFR 121.179 - Airplanes: Reciprocating engine-powered: En route limitations: All engines operating.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Airplanes: Reciprocating engine-powered: En...: CERTIFICATION AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.179 Airplanes: Reciprocating engine-powered: En route limitations: All...

14 CFR 121.179 - Airplanes: Reciprocating engine-powered: En route limitations: All engines operating.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Airplanes: Reciprocating engine-powered: En...: CERTIFICATION AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.179 Airplanes: Reciprocating engine-powered: En route limitations: All...

14 CFR 121.179 - Airplanes: Reciprocating engine-powered: En route limitations: All engines operating.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Airplanes: Reciprocating engine-powered: En...: CERTIFICATION AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.179 Airplanes: Reciprocating engine-powered: En route limitations: All...

Noise-aided computation within a synthetic gene network through morphable and robust logic gates

NASA Astrophysics Data System (ADS)

Dari, Anna; Kia, Behnam; Wang, Xiao; Bulsara, Adi R.; Ditto, William

2011-04-01

An important goal for synthetic biology is to build robust and tunable genetic regulatory networks that are capable of performing assigned operations, usually in the presence of noise. In this work, a synthetic gene network derived from the bacteriophage λ underpins a reconfigurable logic gate wherein we exploit noise and nonlinearity through the application of the logical stochastic resonance paradigm. This biological logic gate can emulate or “morph” the AND and OR operations through varying internal system parameters in a noisy background. Such genetic circuits can afford intriguing possibilities in the realization of engineered genetic networks in which the actual function of the gate can be changed after the network has been built, via an external control parameter. In this article, the full system characterization is reported, with the logic gate performance studied in the presence of external and internal noise. The robustness of the gate, to noise, is studied and illustrated through numerical simulations.

Research and demonstration to improve air quality for the U.S. animal feeding operations in the 21st century - a critical review.

PubMed

Ni, Ji-Qin

2015-05-01

There was an increasing interest in reducing production and emission of air pollutants to improve air quality for animal feeding operations (AFOs) in the U.S. in the 21st century. Research was focused on identification, quantification, characterization, and modeling of air pollutions; effects of emissions; and methodologies and technologies for scientific research and pollution control. Mitigation effects were on pre-excretion, pre-release, pre-emission, and post-emission. More emphasis was given on reducing pollutant emissions than improving indoor air quality. Research and demonstrations were generally continuation and improvement of previous efforts. Most demonstrated technologies were still in a limited scale of application. Future efforts are needed in many fundamental and applied research areas. Advancement in instrumentation, computer technology, and biological sciences and genetic engineering is critical to bring major changes in this area. Development in research and demonstration will depend on the actual political, economic, and environmental situations. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Mars In-Situ-Propellant-Production Precursor (MIP) Flight Demonstration

NASA Technical Reports Server (NTRS)

Kaplan, D. I.; Ratliff, J. E.; Baird, R. S.; Sanders, G. B.; Johnson, K. R.; Karlmann, P. B.; Baraona, C. R.; Landis, G. A.; Jenkins, P. P.; Scheiman, D. A.

1999-01-01

Strategic planning for human missions of exploration to Mars has conclusively identified insitu propellant production (ISPP) as an enabling technology. A team of scientists and engineers from NASA's Johnson Space Center, Jet Propulsion Laboratory, and Glenn Research Center is preparing the MARS ISPP PRECURSOR (MIP) Flight Demonstration. The objectives of MIP are to characterize the performance of processes and hardware that are important to ISPP concepts and to demonstrate how these processes and hardware interact with the Mars environment. Operating this hardware in the actual Mars environment is extremely important due to (1) uncertainties in our knowledge of the Mars environment, and (2) conditions that cannot be adequately simulated on Earth. The MIP Flight Demonstration is a payload onboard the MARS SURVEYOR Lander and will be launched in April 2001. MIP will be the first hardware to utilize the indigenous resources of a planet or moon. Its successful operation will pave the way for future robotic and human missions to rely on propellants produced using Martian resources as feedstock.

Simulation Of Assembly Processes With Technical Of Virtual Reality

NASA Astrophysics Data System (ADS)

García García, Manuel; Arenas Reina, José Manuel; Lite, Alberto Sánchez; Sebastián Pérez, Miguel Ángel

2009-11-01

Virtual reality techniques use at industrial processes provides a real approach to product life cycle. For components manual assembly, the use of virtual surroundings facilitates a simultaneous engineering in which variables such as human factors and productivity take a real act. On the other hand, in the actual phase of industrial competition it is required a rapid adjustment to client needs and to market situation. In this work it is analyzed the assembly of the front components of a vehicle using virtual reality tools and following up a product-process design methodology which includes every life service stage. This study is based on workstations design, taking into account productive and human factors from the ergonomic point of view implementing a postural study of every assembly operation, leaving the rest of stages for a later study. Design is optimized applying this methodology together with the use of virtual reality tools. It is also achieved a 15% reduction on time assembly and of 90% reduction in muscle—skeletal diseases at every assembly operation.

Emerging technologies for V&V of ISHM software for space exploration

NASA Technical Reports Server (NTRS)

Feather, Martin S.; Markosian, Lawrence Z.

2006-01-01

Systems1,2 required to exhibit high operational reliability often rely on some form of fault protection to recognize and respond to faults, preventing faults' escalation to catastrophic failures. Integrated System Health Management (ISHM) extends the functionality of fault protection to both scale to more complex systems (and systems of systems), and to maintain capability rather than just avert catastrophe. Forms of ISHM have been utilized to good effect in the maintenance phase of systems' total lifecycles (often referred to as 'condition-based mainte-nance'), but less so in a 'fault protection' role during actual operations. One of the impediments to such use lies in the challenges of verification, validation and certification of ISHM systems themselves. This paper makes the case that state-of-the-practice V&V and certification techniques will not suffice for emerging forms of ISHM systems; however, a number of maturing software engineering assurance technologies show particular promise for addressing these ISHM V&V challenges.

The reliability evaluation of reclaimed water reused in power plant project

NASA Astrophysics Data System (ADS)

Yang, Jie; Jia, Ru-sheng; Gao, Yu-lan; Wang, Wan-fen; Cao, Peng-qiang

2017-12-01

The reuse of reclaimed water has become one of the important measures to solve the shortage of water resources in many cities, But there is no unified way to evaluate the engineering. Concerning this issue, it took Wanneng power plant project in Huai city as a example, analyzed the reliability of wastewater reuse from the aspects of quality in reclaimed water, water quality of sewage plant, the present sewage quantity in the city and forecast of reclaimed water yield, in particular, it was necessary to make a correction to the actual operation flow rate of the sewage plant. the results showed that on the context of the fluctuation of inlet water quality, the outlet water quality of sewage treatment plants is basically stable, and it can meet the requirement of circulating cooling water, but suspended solids(SS) and total hardness in boiler water exceed the limit, and some advanced treatment should be carried out. In addition, the total sewage discharge will reach 13.91×104m3/d and 14.21×104m3/d respectively in the two planning level years of the project. They are greater than the normal collection capacity of the sewage system which is 12.0×104 m3/d, and the reclaimed water yield can reach 10.74×104m3/d, which is greater than the actual needed quantity 8.25×104m3/d of the power plant, so the wastewater reuse of this sewage plant are feasible and reliable to the power plant in view of engineering.

Defining Gas Turbine Engine Performance Requirements for the Large Civil TiltRotor (LCTR2)

NASA Technical Reports Server (NTRS)

Snyder, Christopher A.

2013-01-01

Defining specific engine requirements is a critical part of identifying technologies and operational models for potential future rotary wing vehicles. NASA's Fundamental Aeronautics Program, Subsonic Rotary Wing Project has identified the Large Civil TiltRotor (LCTR) as the configuration to best meet technology goals. This notional vehicle concept has evolved with more clearly defined mission and operational requirements to the LCTR-iteration 2 (LCTR2). This paper reports on efforts to further review and refine the LCTR2 analyses to ascertain specific engine requirements and propulsion sizing criteria. The baseline mission and other design or operational requirements are reviewed. Analysis tools are described to help understand their interactions and underlying assumptions. Various design and operational conditions are presented and explained for their contribution to defining operational and engine requirements. These identified engine requirements are discussed to suggest which are most critical to the engine sizing and operation. The most-critical engine requirements are compared to in-house NASA engine simulations to try to ascertain which operational requirements define engine requirements versus points within the available engine operational capability. Finally, results are summarized with suggestions for future efforts to improve analysis capabilities, and better define and refine mission and operational requirements.

The nonrelativistic limit of (central-extended) Poincaré group and some consequences for quantum actualization

NASA Astrophysics Data System (ADS)

Ardenghi, Juan S.; Castagnino, M.; Campoamor-Stursberg, R.

2009-10-01

The nonrelativistic limit of the centrally extended Poincaré group is considered and their consequences in the modal Hamiltonian interpretation of quantum mechanics are discussed [O. Lombardi and M. Castagnino, Stud. Hist. Philos. Mod. Phys 39, 380 (2008); J. Phys, Conf. Ser. 128, 012014 (2008)]. Through the assumption that in quantum field theory the Casimir operators of the Poincaré group actualize, the nonrelativistic limit of the latter group yields to the actualization of the Casimir operators of the Galilei group, which is in agreement with the actualization rule of previous versions of modal Hamiltonian interpretation [Ardenghi et al., Found. Phys. (submitted)].

Fuel cell stack monitoring and system control

DOEpatents

Keskula, Donald H.; Doan, Tien M.; Clingerman, Bruce J.

2004-02-17

A control method for monitoring a fuel cell stack in a fuel cell system in which the actual voltage and actual current from the fuel cell stack are monitored. A preestablished relationship between voltage and current over the operating range of the fuel cell is established. A variance value between the actual measured voltage and the expected voltage magnitude for a given actual measured current is calculated and compared with a predetermined allowable variance. An output is generated if the calculated variance value exceeds the predetermined variance. The predetermined voltage-current for the fuel cell is symbolized as a polarization curve at given operating conditions of the fuel cell.

14 CFR 25.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Turbine engine operating characteristics... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be investigated in...

14 CFR 25.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Turbine engine operating characteristics... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be investigated in...

14 CFR 25.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Turbine engine operating characteristics... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be investigated in...

14 CFR 25.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Turbine engine operating characteristics... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be investigated in...

14 CFR 25.939 - Turbine engine operating characteristics.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Turbine engine operating characteristics... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Powerplant General § 25.939 Turbine engine operating characteristics. (a) Turbine engine operating characteristics must be investigated in...

Software package for performing experiments about the convolutionally encoded Voyager 1 link

NASA Technical Reports Server (NTRS)

Cheng, U.

1989-01-01

A software package enabling engineers to conduct experiments to determine the actual performance of long constraint-length convolutional codes over the Voyager 1 communication link directly from the Jet Propulsion Laboratory (JPL) has been developed. Using this software, engineers are able to enter test data from the Laboratory in Pasadena, California. The software encodes the data and then sends the encoded data to a personal computer (PC) at the Goldstone Deep Space Complex (GDSC) over telephone lines. The encoded data are sent to the transmitter by the PC at GDSC. The received data, after being echoed back by Voyager 1, are first sent to the PC at GDSC, and then are sent back to the PC at the Laboratory over telephone lines for decoding and further analysis. All of these operations are fully integrated and are completely automatic. Engineers can control the entire software system from the Laboratory. The software encoder and the hardware decoder interface were developed for other applications, and have been modified appropriately for integration into the system so that their existence is transparent to the users. This software provides: (1) data entry facilities, (2) communication protocol for telephone links, (3) data displaying facilities, (4) integration with the software encoder and the hardware decoder, and (5) control functions.

Characterization of performance-emission indices of a diesel engine using ANFIS operating in dual-fuel mode with LPG

NASA Astrophysics Data System (ADS)

Chakraborty, Amitav; Roy, Sumit; Banerjee, Rahul

2018-03-01

This experimental work highlights the inherent capability of an adaptive-neuro fuzzy inference system (ANFIS) based model to act as a robust system identification tool (SIT) in prognosticating the performance and emission parameters of an existing diesel engine running of diesel-LPG dual fuel mode. The developed model proved its adeptness by successfully harnessing the effects of the input parameters of load, injection duration and LPG energy share on output parameters of BSFCEQ, BTE, NOX, SOOT, CO and HC. Successive evaluation of the ANFIS model, revealed high levels of resemblance with the already forecasted ANN results for the same input parameters and it was evident that similar to ANN, ANFIS also has the innate ability to act as a robust SIT. The ANFIS predicted data harmonized the experimental data with high overall accuracy. The correlation coefficient (R) values are stretched in between 0.99207 to 0.999988. The mean absolute percentage error (MAPE) tallies were recorded in the range of 0.02-0.173% with the root mean square errors (RMSE) in acceptable margins. Hence the developed model is capable of emulating the actual engine parameters with commendable ranges of accuracy, which in turn would act as a robust prediction platform in the future domains of optimization.

NDE standards for high temperature materials

NASA Technical Reports Server (NTRS)

Vary, Alex

1991-01-01

High temperature materials include monolithic ceramics for automotive gas turbine engines and also metallic/intermetallic and ceramic matrix composites for a range of aerospace applications. These are materials that can withstand extreme operating temperatures that will prevail in advanced high-efficiency gas turbine engines. High temperature engine components are very likely to consist of complex composite structures with three-dimensionality interwoven and various intermixed ceramic fibers. The thermomechanical properties of components made of these materials are actually created in-place during processing and fabrication stages. The complex nature of these new materials creates strong incentives for exact standards for unambiguous evaluations of defects and microstructural characteristics. NDE techniques and standards that will ultimately be applicable to production and quality control of high temperature materials and structures are still emerging. The needs range from flaw detection to below 100 micron levels in monolithic ceramics to global imaging of fiber architecture and matrix densification anomalies in composites. The needs are different depending on the processing stage, fabrication method, and nature of the finished product. The standards are discussed that must be developed in concert with advances in NDE technology, materials processing research, and fabrication development. High temperature materials and structures that fail to meet stringent specifications and standards are unlikely to compete successfully either technologically or in international markets.

On the hazard of quiet vehicles to pedestrians and drivers.

PubMed

Wogalter, Michael S; Lim, Raymond W; Nyeste, Patrick G

2014-09-01

The need to produce more efficient and less polluting vehicles has encouraged mass production of alternative energy vehicles, such as hybrid and electric cars. Many of these vehicles are capable of very quiet operation. While reducing noise pollution is desirable, quieter vehicles could negatively affect pedestrian safety because of reduced sound cues compared to louder internal combustion engines. Three studies were performed to investigate people's concern about this issue. In Study 1, a questionnaire completed by 378 people showed substantial positive interest in quiet hybrid and electric cars. However, they also indicated concern about the reduced auditory cues of quiet vehicles. In Study 2, 316 participants rated 14 sounds that could be potentially added to quiet alternative-energy vehicles. The data showed that participants did not want annoying sounds, but preferred adding "engine" and "hum" sounds relative to other types of sounds. In Study 3, 24 persons heard and rated 18 actual sounds within 6 categories that were added to a video of a hybrid vehicle driving by. The sounds most preferred were "engine" followed by "white noise" and "hum". Implications for adding sounds to facilitate pedestrians' detection of moving vehicles and for aiding drivers' awareness of speed are discussed. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Simulator of Space Communication Networks

NASA Technical Reports Server (NTRS)

Clare, Loren; Jennings, Esther; Gao, Jay; Segui, John; Kwong, Winston

2005-01-01

Multimission Advanced Communications Hybrid Environment for Test and Evaluation (MACHETE) is a suite of software tools that simulates the behaviors of communication networks to be used in space exploration, and predict the performance of established and emerging space communication protocols and services. MACHETE consists of four general software systems: (1) a system for kinematic modeling of planetary and spacecraft motions; (2) a system for characterizing the engineering impact on the bandwidth and reliability of deep-space and in-situ communication links; (3) a system for generating traffic loads and modeling of protocol behaviors and state machines; and (4) a system of user-interface for performance metric visualizations. The kinematic-modeling system makes it possible to characterize space link connectivity effects, including occultations and signal losses arising from dynamic slant-range changes and antenna radiation patterns. The link-engineering system also accounts for antenna radiation patterns and other phenomena, including modulations, data rates, coding, noise, and multipath fading. The protocol system utilizes information from the kinematic-modeling and link-engineering systems to simulate operational scenarios of space missions and evaluate overall network performance. In addition, a Communications Effect Server (CES) interface for MACHETE has been developed to facilitate hybrid simulation of space communication networks with actual flight/ground software/hardware embedded in the overall system.

40 CFR 74.22 - Actual SO2 emissions rate.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Actual SO2 emissions rate. 74.22... (CONTINUED) SULFUR DIOXIDE OPT-INS Allowance Calculations for Combustion Sources § 74.22 Actual SO2 emissions... actual SO2 emissions rate shall be 1985. (2) For combustion sources that commenced operation after...

Engine Seal Technology Requirements to Meet NASA's Advanced Subsonic Technology Program Goals

NASA Technical Reports Server (NTRS)

Steinetz, Bruce M.; Hendricks, Robert C.

1994-01-01

Cycle studies have shown the benefits of increasing engine pressure ratios and cycle temperatures to decrease engine weight and improve performance of commercial turbine engines. NASA is working with industry to define technology requirements of advanced engines and engine technology to meet the goals of NASA's Advanced Subsonic Technology Initiative. As engine operating conditions become more severe and customers demand lower operating costs, NASA and engine manufacturers are investigating methods of improving engine efficiency and reducing operating costs. A number of new technologies are being examined that will allow next generation engines to operate at higher pressures and temperatures. Improving seal performance - reducing leakage and increasing service life while operating under more demanding conditions - will play an important role in meeting overall program goals of reducing specific fuel consumption and ultimately reducing direct operating costs. This paper provides an overview of the Advanced Subsonic Technology program goals, discusses the motivation for advanced seal development, and highlights seal technology requirements to meet future engine performance goals.

MAPGEN: Mixed-Initiative Activity Planning for the Mars Exploration Rover Mission

NASA Technical Reports Server (NTRS)

Ai-Chang, Mitchell; Bresina, John; Hsu, Jennifer; Jonsson, Ari; Kanefsky, Bob; McCurdy, Michael; Morris, Paul; Rajan, Kanna; Vera, Alonso; Yglesias, Jeffrey

2004-01-01

This document describes the Mixed initiative Activity Plan Generation system MAPGEN. This system is one of the critical tools in the Mars Exploration Rover mission surface operations, where it is used to build activity plans for each of the rovers, each Martian day. The MAPGEN system combines an existing tool for activity plan editing and resource modeling, with an advanced constraint-based reasoning and planning framework. The constraint-based planning component provides active constraint and rule enforcement, automated planning capabilities, and a variety of tools and functions that are useful for building activity plans in an interactive fashion. In this demonstration, we will show the capabilities of the system and demonstrate how the system has been used in actual Mars rover operations. In contrast to the demonstration given at ICAPS 03, significant improvement have been made to the system. These include various additional capabilities that are based on automated reasoning and planning techniques, as well as a new Constraint Editor support tool. The Constraint Editor (CE) as part of the process for generating these command loads, the MAPGEN tool provides engineers and scientists an intelligent activity planning tool that allows them to more effectively generate complex plans that maximize the science return each day. The key to the effectiveness of the MAPGEN tool is an underlying constraint-based planning and reasoning engine.

Software and cyber-infrastructure development to control the Observatorio Astrofísico de Javalambre (OAJ)

NASA Astrophysics Data System (ADS)

Yanes-Díaz, A.; Antón, J. L.; Rueda-Teruel, S.; Guillén-Civera, L.; Bello, R.; Jiménez-Mejías, D.; Chueca, S.; Lasso-Cabrera, N. M.; Suárez, O.; Rueda-Teruel, F.; Cenarro, A. J.; Cristobal-Hornillos, D.; Marin-Franch, A.; Luis-Simoes, R.; López-Alegre, G.; Rodríguez-Hernández, M. A. C.; Moles, M.; Ederoclite, A.; Varela, J.; Vazquez Ramió, H.; Díaz-Martín, M. C.; Iglesias-Marzoa, R.; Maicas, N.; Lamadrid, J. L.; Lopez-Sainz, A.; Hernández-Fuertes, J.; Valdivielso, L.; Mendes de Oliveira, C.; Penteado, P.; Schoenell, W.; Kanaan, A.

2014-07-01

The Observatorio Astrofísico de Javalambre (OAJ) is a new astronomical facility located at the Sierra de Javalambre (Teruel, Spain) whose primary role will be to conduct all-sky astronomical surveys with two unprecedented telescopes of unusually large fields of view: the JST/T250, a 2.55m telescope of 3deg field of view, and the JAST/T80, an 83cm telescope of 2deg field of view. CEFCA engineering team has been designing the OAJ control system as a global concept to manage, monitor, control and maintain all the observatory systems including not only astronomical subsystems but also infrastructure and other facilities. In order to provide quality, reliability and efficiency, the OAJ control system (OCS) design is based on CIA (Control Integrated Architecture) and OEE (Overall Equipment Effectiveness) as a key to improve day and night operation processes. The OCS goes from low level hardware layer including IOs connected directly to sensors and actuators deployed around the whole observatory systems, including telescopes and astronomical instrumentation, up to the high level software layer as a tool to perform efficiently observatory operations. We will give an overview of the OAJ control system design and implementation from an engineering point of view, giving details of the design criteria, technology, architecture, standards, functional blocks, model structure, development, deployment, goals, report about the actual status and next steps.

A New Handbook for the Development of Space Vehicle Terrestrial Environment Design Requirements.

NASA Technical Reports Server (NTRS)

Johnson, Dale L.; Vaughan, William W.

2008-01-01

A new NASA document entitled "Terrestrial Environment (Climatic) Criteria Handbook for Use in Aerospace Vehicle Development (NASA-HDBK-1001A) has been developed. The Handbook provides terrestrial environment information, data bases, models, recommendations, etc. for use in the design, development, trade studies, testing, and mission analyses for space (or launch) .vehicles. This document is organized into fourteen specific natural environment disciplines of which some are winds, atmospheric models, thermal radiation, precipitation-for-icing, cloud cover, atmospheric electricity, geologic hazards, toxic chemical release by propulsion systems, and sea state. Atmospheric phenomena play a significant role in the design and flight of aerospace vehicles and in the integrity of the associated aerospace systems and structures. Environmental design criteria guidelines in this document are based on measurements and observations of atmospheric and climatic phenomena relative to various aerospace development, operational, and vehicle launch locations. The natural environment criteria guidelines data presented in this Handbook were formulated based on discussions with and requests from engineers involved in aerospace vehicle development and operations. Therefore, they represent responses to actual engineering problems and are not just a general compilation of environmental data. The Handbook addresses the basis for the information presented, the interpretations of the terrestrial environment guideline given in the Handbook, and its application to the development of aerospace vehicle design requirements. Specific examples of the Handbook content and associated "lessons lenmed" are given in this paper.

A review of engineering aspects of intensification of chemical synthesis using ultrasound.

PubMed

Sancheti, Sonam V; Gogate, Parag R

2017-05-01

Cavitation generated using ultrasound can enhance the rates of several chemical reactions giving better selectivity based on the physical and chemical effects. The present review focuses on overview of the different reactions that can be intensified using ultrasound followed by the discussion on the chemical kinetics for ultrasound assisted reactions, engineering aspects related to reactor designs and effect of operating parameters on the degree of intensification obtained for chemical synthesis. The cavitational effects in terms of magnitudes of collapse temperatures and collapse pressure, number of free radicals generated and extent of turbulence are strongly dependent on the operating parameters such as ultrasonic power, frequency, duty cycle, temperature as well as physicochemical parameters of liquid medium which controls the inception of cavitation. Guidelines have been presented for the optimum selection based on the critical analysis of the existing literature so that maximum process intensification benefits can be obtained. Different reactor designs have also been analyzed with guidelines for efficient scale up of the sonochemical reactor, which would be dependent on the type of reaction, controlling mechanism of reaction, catalyst and activation energy requirements. Overall, it has been established that sonochemistry offers considerable potential for green and sustainable processing and efficient scale up procedures are required so as to harness the effects at actual commercial level. Copyright © 2016 Elsevier B.V. All rights reserved.

Manchester visual query language

NASA Astrophysics Data System (ADS)

Oakley, John P.; Davis, Darryl N.; Shann, Richard T.

1993-04-01

We report a database language for visual retrieval which allows queries on image feature information which has been computed and stored along with images. The language is novel in that it provides facilities for dealing with feature data which has actually been obtained from image analysis. Each line in the Manchester Visual Query Language (MVQL) takes a set of objects as input and produces another, usually smaller, set as output. The MVQL constructs are mainly based on proven operators from the field of digital image analysis. An example is the Hough-group operator which takes as input a specification for the objects to be grouped, a specification for the relevant Hough space, and a definition of the voting rule. The output is a ranked list of high scoring bins. The query could be directed towards one particular image or an entire image database, in the latter case the bins in the output list would in general be associated with different images. We have implemented MVQL in two layers. The command interpreter is a Lisp program which maps each MVQL line to a sequence of commands which are used to control a specialized database engine. The latter is a hybrid graph/relational system which provides low-level support for inheritance and schema evolution. In the paper we outline the language and provide examples of useful queries. We also describe our solution to the engineering problems associated with the implementation of MVQL.

A New Handbook for the Development of Space Vehicle Terrestrial Environment Design Requirements

NASA Technical Reports Server (NTRS)

Johnson, Dale L.; Vaughan, William W.

2008-01-01

A new NASA document entitled "Terrestrial Environment (Climatic) Criteria Handbook for Use in Aerospace Vehicle Development (NASA-HDBK-IOO1A) has been developed. The Handbook provides terrestrial environment information, data bases, models, recommendations, etc. for use in the design, development, trade studies, testing, and mission analyses for space (or launch) vehicles. This document is organized into fourteen specific natural environment disciplines of which some are winds, atmospheric models, thermal radiation, precipitation-for-icing, cloud cover, atmospheric electricity, geologic hazards, toxic chemical release by propulsion systems, and sea state. Atmospheric phenomena play a significant role in the design and flight of aerospace vehicles and in the integrity of the associated aerospace systems and structures. Environmental design criteria guidelines in this document are based on measurements and observations of atmospheric and climatic phenomena relative to various aerospace development, operational, and vehicle launch locations. The natural environment criteria guidelines data presented in this Handbook were formulated based on discussions with and requests from engineers involved in aerospace vehicle development and operations. Therefore, they represent responses to actual engineering problems and are not just a general compilation of environmental data. The Handbook addresses the basis for the information presented, the interpretations of the terrestrial environment guideline given in the Handbook, and its application to the development of aerospace vehicle design requirements. Specific examples of the Handbook content and associated "lessons lenmed" are given in this paper.

Spontaneous Raman Scattering (SRS) System for Calibrating High-Pressure Flames Became Operational

NASA Technical Reports Server (NTRS)

Nguyen, Quang-Viet

2003-01-01

A high-performance spontaneous Raman scattering (SRS) system for measuring quantitative species concentration and temperature in high-pressure flames is now operational. The system is located in Glenn s Engine Research Building. Raman scattering is perhaps the only optical diagnostic technique that permits the simultaneous (single-shot) measurement of all major species (N2, O2, CO2, H2O, CO, H2, and CH4) as well as temperature in combustion systems. The preliminary data acquired with this new system in a 20-atm hydrogen-air (H2-air) flame show excellent spectral coverage, good resolution, and a signal-to-noise ratio high enough for the data to serve as a calibration standard. This new SRS diagnostic system is used in conjunction with the newly developed High- Pressure Gaseous Burner facility (ref. 1). The main purpose of this diagnostic system and the High-Pressure Gaseous Burner facility is to acquire and establish a comprehensive Raman-scattering spectral database calibration standard for the combustion diagnostic community. A secondary purpose of the system is to provide actual measurements in standardized flames to validate computational combustion models. The High-Pressure Gaseous Burner facility and its associated SRS system will provide researchers throughout the world with new insights into flame conditions that simulate the environment inside the ultra-high-pressure-ratio combustion chambers of tomorrow s advanced aircraft engines.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Flanigan, Tom; Pybus, Craig; Roy, Sonya

This report summarizes the results of the Pre-Front End Engineering Design (pre-FEED) phase of a proposed advanced oxy-combustion power generation plant to repower the existing 200 MWe Unit 4 at Ameren Energy Resources’ (AER) Meredosia Power Plant. AER has formed an alliance with Air Liquide Process and Construction, Inc. (ALPC) and Babcock & Wilcox Power Generation Group (B&W PGG) for the design, construction, and testing of the facility, and has contracted with URS Corporation (URS) for preliminary design and Owner’s engineering services. The Project employs oxy-combustion technology – combustion of coal with nearly pure oxygen and recycled flue gas (insteadmore » of air) – to capture approximately 90% of the flue gas CO2 for transport and sequestration by another Project. Plant capacity and configuration has been developed based on the B&W PGG-ALPC cool recycle process firing high-sulfur bituminous coal fuel, assuming baseload plant operation to maximize existing steam turbine capability, with limited consideration for plant redundancy and performance optimization in order to keep plant costs as low as practical. Activities and preliminary results from the pre-FEED phase addressed in this report include the following: Overall plant thermal performance; Equipment sizing and system configuration; Plant operation and control philosophy; Plant emissions and effluents; CO 2 production and recovery characteristics; Project cost estimate and economic evaluation; Integrated project engineering and construction schedule; Project risk and opportunity assessment; Development of Project permitting strategy and requirements During the Phase 2 of the Project, additional design details will be developed and the Phase 1 work products updated to support actual construction and operation of the facility in Phase 3. Additional information will be provided early in Phase 2 to support Ameren-Environmental in finalizing the appropriate permitting strategies and permit applications. Additional performance and reliability enhancements will also be evaluated in Phase 2 to try to improve overall project economics.« less

A sustained-arc ignition system for internal combustion engines

NASA Technical Reports Server (NTRS)

Birchenough, A. G.

1977-01-01

A sustained-arc ignition system was developed for internal combustion engines. It produces a very-long-duration ignition pulse with an energy in the order of 100 millijoules. The ignition pulse waveform can be controlled to predetermined actual ignition requirements. The design of the sustained-arc ignition system is presented in the report.

Cooperative solutions coupling a geometry engine and adaptive solver codes

NASA Technical Reports Server (NTRS)

Dickens, Thomas P.

1995-01-01

Follow-on work has progressed in using Aero Grid and Paneling System (AGPS), a geometry and visualization system, as a dynamic real time geometry monitor, manipulator, and interrogator for other codes. In particular, AGPS has been successfully coupled with adaptive flow solvers which iterate, refining the grid in areas of interest, and continuing on to a solution. With the coupling to the geometry engine, the new grids represent the actual geometry much more accurately since they are derived directly from the geometry and do not use refits to the first-cut grids. Additional work has been done with design runs where the geometric shape is modified to achieve a desired result. Various constraints are used to point the solution in a reasonable direction which also more closely satisfies the desired results. Concepts and techniques are presented, as well as examples of sample case studies. Issues such as distributed operation of the cooperative codes versus running all codes locally and pre-calculation for performance are discussed. Future directions are considered which will build on these techniques in light of changing computer environments.

Genetically engineered microorganisms for the detection of explosives’ residues

PubMed Central

Shemer, Benjamin; Palevsky, Noa; Yagur-Kroll, Sharon; Belkin, Shimshon

2015-01-01

The manufacture and use of explosives throughout the past century has resulted in the extensive pollution of soils and groundwater, and the widespread interment of landmines imposes a major humanitarian risk and prevents civil development of large areas. As most current landmine detection technologies require actual presence at the surveyed areas, thus posing a significant risk to personnel, diverse research efforts are aimed at the development of remote detection solutions. One possible means proposed to fulfill this objective is the use of microbial bioreporters: genetically engineered microorganisms “tailored” to generate an optical signal in the presence of explosives’ vapors. The use of such sensor bacteria will allow to pinpoint the locations of explosive devices in a minefield. While no study has yet resulted in a commercially operational system, significant progress has been made in the design and construction of explosives-sensing bacterial strains. In this article we review the attempts to construct microbial bioreporters for the detection of explosives, and analyze the steps that need to be undertaken for this strategy to be applicable for landmine detection. PMID:26579085

Feasibility of using a knowledge-based system concept for in-flight primary flight display research

NASA Technical Reports Server (NTRS)

Ricks, Wendell R.

1991-01-01

A study was conducted to determine the feasibility of using knowledge-based systems architectures for inflight research of primary flight display information management issues. The feasibility relied on the ability to integrate knowledge-based systems with existing onboard aircraft systems. And, given the hardware and software platforms available, the feasibility also depended on the ability to use interpreted LISP software with the real time operation of the primary flight display. In addition to evaluating these feasibility issues, the study determined whether the software engineering advantages of knowledge-based systems found for this application in the earlier workstation study extended to the inflight research environment. To study these issues, two integrated knowledge-based systems were designed to control the primary flight display according to pre-existing specifications of an ongoing primary flight display information management research effort. These two systems were implemented to assess the feasibility and software engineering issues listed. Flight test results were successful in showing the feasibility of using knowledge-based systems inflight with actual aircraft data.

Hybrid power supplies: A capacitor-assisted battery

NASA Astrophysics Data System (ADS)

Catherino, Henry A.; Burgel, Joseph F.; Shi, Peter L.; Rusek, Andrew; Zou, Xiulin

A hybrid electrochemical power supply is a concept that circumvents the need for designing any single power source to meet some extraordinary application requirement. A hybrid allows using components designed for near optimal operation without having to make unnecessary performance sacrifices. In many cases some additional synergistic effects appear. In this study, an electrochemical capacitor was employed as a power assist for a battery. An engine starting load was numerically modeled in the time domain and simulations were carried out. Actual measurements were then taken on the cranking of a diesel engine removed from a 5.0-tonne military truck and cranked in an environmental chamber. The cranking currents delivered by each power source were measured in the accessible current loops. This permitted the model parameters to be identified and, by doing that, studies using the analytical model demonstrated the merit of this hybrid application. The general system response of the battery/capacitor configuration was then modeled as a function of temperature. Doing this revealed electrical the interaction between the hybrid components. This study illustrates another case for advocating hybridized power systems.

Rule-based simulation models

NASA Technical Reports Server (NTRS)

Nieten, Joseph L.; Seraphine, Kathleen M.

1991-01-01

Procedural modeling systems, rule based modeling systems, and a method for converting a procedural model to a rule based model are described. Simulation models are used to represent real time engineering systems. A real time system can be represented by a set of equations or functions connected so that they perform in the same manner as the actual system. Most modeling system languages are based on FORTRAN or some other procedural language. Therefore, they must be enhanced with a reaction capability. Rule based systems are reactive by definition. Once the engineering system has been decomposed into a set of calculations using only basic algebraic unary operations, a knowledge network of calculations and functions can be constructed. The knowledge network required by a rule based system can be generated by a knowledge acquisition tool or a source level compiler. The compiler would take an existing model source file, a syntax template, and a symbol table and generate the knowledge network. Thus, existing procedural models can be translated and executed by a rule based system. Neural models can be provide the high capacity data manipulation required by the most complex real time models.

Revitalizing the Space Shuttle's Thermal Protection System with Reverse Engineering and 3D Vision Technology

NASA Technical Reports Server (NTRS)

Wilson, Brad; Galatzer, Yishai

2008-01-01

The Space Shuttle is protected by a Thermal Protection System (TPS) made of tens of thousands of individually shaped heat protection tile. With every flight, tiles are damaged on take-off and return to earth. After each mission, the heat tiles must be fixed or replaced depending on the level of damage. As part of the return to flight mission, the TPS requirements are more stringent, leading to a significant increase in heat tile replacements. The replacement operation requires scanning tile cavities, and in some cases the actual tiles. The 3D scan data is used to reverse engineer each tile into a precise CAD model, which in turn, is exported to a CAM system for the manufacture of the heat protection tile. Scanning is performed while other activities are going on in the shuttle processing facility. Many technicians work simultaneously on the space shuttle structure, which results in structural movements and vibrations. This paper will cover a portable, ultra-fast data acquisition approach used to scan surfaces in this unstable environment.

Shuttle Repair Tools Automate Vehicle Maintenance

NASA Technical Reports Server (NTRS)

2013-01-01

Successfully building, flying, and maintaining the space shuttles was an immensely complex job that required a high level of detailed, precise engineering. After each shuttle landed, it entered a maintenance, repair, and overhaul (MRO) phase. Each system was thoroughly checked and tested, and worn or damaged parts replaced, before the shuttle was rolled out for its next mission. During the MRO period, workers needed to record exactly what needed replacing and why, as well as follow precise guidelines and procedures in making their repairs. That meant traceability, and with it lots of paperwork. In 2007, the number of reports generated during electrical system repairs was getting out of hand-placing among the top three systems in terms of paperwork volume. Repair specialists at Kennedy Space Center were unhappy spending so much time at a desk and so little time actually working on the shuttle. "Engineers weren't spending their time doing technical work," says Joseph Schuh, an electrical engineer at Kennedy. "Instead, they were busy with repetitive, time-consuming processes that, while important in their own right, provided a low return on time invested." The strain of such inefficiency was bad enough that slow electrical repairs jeopardized rollout on several occasions. Knowing there had to be a way to streamline operations, Kennedy asked Martin Belson, a project manager with 30 years experience as an aerospace contractor, to co-lead a team in developing software that would reduce the effort required to document shuttle repairs. The result was System Maintenance Automated Repair Tasks (SMART) software. SMART is a tool for aggregating and applying information on every aspect of repairs, from procedures and instructions to a vehicle s troubleshooting history. Drawing on that data, SMART largely automates the processes of generating repair instructions and post-repair paperwork. In the case of the space shuttle, this meant that SMART had 30 years worth of operations that it could apply to ongoing maintenance work. According to Schuh, "SMART standardized and streamlined many shuttle repair processes, saving time and money while increasing safety and the quality of repairs." Maintenance technicians and engineers now had a tool that kept them in the field, and because SMART is capable of continually evolving, each time an engineer put it to use, it would enrich the Agency-wide knowledge base. "If an engineer sees something in the work environment that they could improve, a repair process or a procedure, SMART can incorporate that data for use in future operations," says Belson.

Simultaneous dual mode combustion engine operating on spark ignition and homogenous charge compression ignition

DOEpatents

Fiveland, Scott B.; Wiggers, Timothy E.

2004-06-22

An engine particularly suited to single speed operation environments, such as stationary power generators. The engine includes a plurality of combustion cylinders operable under homogenous charge compression ignition, and at least one combustion cylinder operable on spark ignition concepts. The cylinder operable on spark ignition concepts can be convertible to operate under homogenous charge compression ignition. The engine is started using the cylinders operable under spark ignition concepts.

Human Factors in the Design of the Crew Exploration Vehicle (CEV)

NASA Technical Reports Server (NTRS)

Whitmore, Mihriban; Byrne, Vicky; Holden, Kritina

2007-01-01

NASA s Space Exploration vision for humans to venture to the moon and beyond provides interesting human factors opportunities and challenges. The Human Engineering group at NASA has been involved in the initial phases of development of the Crew Exploration Vehicle (CEV), Orion. Getting involved at the ground level, Human Factors engineers are beginning to influence design; this involvement is expected to continue throughout the development lifecycle. The information presented here describes what has been done to date, what is currently going on, and what is expected in the future. During Phase 1, prior to the contract award to Lockheed Martin, the Human Engineering group was involved in generating requirements, conducting preliminary task analyses based on interviews with subject matter experts in all vehicle systems areas, and developing preliminary concepts of operations based on the task analysis results. In addition, some early evaluations to look at CEV net habitable volume were also conducted. The program is currently in Phase 2, which is broken down into design cycles, including System Readiness Review, Preliminary Design Review, and Critical Design Review. Currently, there are ongoing Human Engineering Technical Interchange Meetings being held with both NASA and Lockheed Martin in order to establish processes, desired products, and schedules. Multiple design trades and quick-look evaluations (e.g. display device layout and external window size) are also in progress. Future Human Engineering activities include requirement verification assessments and crew/stakeholder evaluations of increasing fidelity. During actual flights of the CEV, the Human Engineering group is expected to be involved in in-situ testing and lessons learned reporting, in order to benefit human space flight beyond the initial CEV program.

Engineering and Scientific Applications: Using MatLab(Registered Trademark) for Data Processing and Visualization

NASA Technical Reports Server (NTRS)

Sen, Syamal K.; Shaykhian, Gholam Ali

2011-01-01

MatLab(TradeMark)(MATrix LABoratory) is a numerical computation and simulation tool that is used by thousands Scientists and Engineers in many countries. MatLab does purely numerical calculations, which can be used as a glorified calculator or interpreter programming language; its real strength is in matrix manipulations. Computer algebra functionalities are achieved within the MatLab environment using "symbolic" toolbox. This feature is similar to computer algebra programs, provided by Maple or Mathematica to calculate with mathematical equations using symbolic operations. MatLab in its interpreter programming language form (command interface) is similar with well known programming languages such as C/C++, support data structures and cell arrays to define classes in object oriented programming. As such, MatLab is equipped with most of the essential constructs of a higher programming language. MatLab is packaged with an editor and debugging functionality useful to perform analysis of large MatLab programs and find errors. We believe there are many ways to approach real-world problems; prescribed methods to ensure foregoing solutions are incorporated in design and analysis of data processing and visualization can benefit engineers and scientist in gaining wider insight in actual implementation of their perspective experiments. This presentation will focus on data processing and visualizations aspects of engineering and scientific applications. Specifically, it will discuss methods and techniques to perform intermediate-level data processing covering engineering and scientific problems. MatLab programming techniques including reading various data files formats to produce customized publication-quality graphics, importing engineering and/or scientific data, organizing data in tabular format, exporting data to be used by other software programs such as Microsoft Excel, data presentation and visualization will be discussed.

Altitude Wind Tunnel Drive Fan being Assembled

NASA Image and Video Library

1943-07-21

National Advisory Committee for Aeronautics (NACA) engineers assembled the Altitude Wind Tunnel’s (AWT) large wooden drive fan inside the hangar at the Aircraft Engine Research Laboratory. When it was built at the in the early 1940s the AWT was among the most complex test facilities ever designed. It was the first wind tunnel capable of operating full-scale engines under realistic flight conditions. This simulation included the reduction of air temperature, a decrease in air pressure, and the creation of an airstream velocity of up to 500 miles per hour. The AWT was constructed in 1942 and 1943. This photograph shows NACA engineers Lou Hermann and Jack Aust assembling the tunnel’s drive fan inside the hangar. The 12-bladed, 31-foot-diameter spruce wood fan would soon be installed inside the wind tunnel to create the high-speed airflow. This massive propeller was designed and constructed by the engine lab's design team at Langley Field. John Breisch, a Langley technician with several years of wind tunnel installation experience, arrived in Cleveland at the time of this photograph to supervise the fan assembly inside the hangar. He would return several weeks later to oversee the actual installation in the tunnel. The fan was driven at 410 revolutions per minute by an 18,000-horsepower General Electric induction motor that was located in the rear corner of the Exhauster Building. An extension shaft connected the motor to the fan. A bronze screen protected the fan against damage from failed engine parts sailing through the tunnel. Despite this screen the blades did become worn or cracked over time and had to be replaced. An entire new fan was installed in 1951.

Pulse Detonation Engine Test Bed Developed

NASA Technical Reports Server (NTRS)

Breisacher, Kevin J.

2002-01-01

A detonation is a supersonic combustion wave. A Pulse Detonation Engine (PDE) repetitively creates a series of detonation waves to take advantage of rapid burning and high peak pressures to efficiently produce thrust. NASA Glenn Research Center's Combustion Branch has developed a PDE test bed that can reproduce the operating conditions that might be encountered in an actual engine. It allows the rapid and cost-efficient evaluation of the technical issues and technologies associated with these engines. The test bed is modular in design. It consists of various length sections of both 2- and 2.6- in. internal-diameter combustor tubes. These tubes can be bolted together to create a variety of combustor configurations. A series of bosses allow instrumentation to be inserted on the tubes. Dynamic pressure sensors and heat flux gauges have been used to characterize the performance of the test bed. The PDE test bed is designed to utilize an existing calorimeter (for heat load measurement) and windowed (for optical access) combustor sections. It uses hydrogen as the fuel, and oxygen and nitrogen are mixed to simulate air. An electronic controller is used to open the hydrogen and air valves (or a continuous flow of air is used) and to fire the spark at the appropriate times. Scheduled tests on the test bed include an evaluation of the pumping ability of the train of detonation waves for use in an ejector and an evaluation of the pollutants formed in a PDE combustor. Glenn's Combustion Branch uses the National Combustor Code (NCC) to perform numerical analyses of PDE's as well as to evaluate alternative detonative combustion devices. Pulse Detonation Engine testbed.

An experimental study of the stable and unstable operation of an LPP gas turbine combustor

NASA Astrophysics Data System (ADS)

Dhanuka, Sulabh Kumar

A study was performed to better understand the stable operation of an LPP combustor and formulate a mechanism behind the unstable operation. A unique combustor facility was developed at the University of Michigan that incorporates the latest injector developed by GE Aircraft Engines and enables operation at elevated pressures with preheated air at flow-rates reflective of actual conditions. The large optical access has enabled the use of a multitude of state-of-the-art laser diagnostics such as PIV and PLIF, and has shed invaluable light not only into the GE injector specifically but also into gas turbine combustors in general. Results from Particle Imaging Velocimetry (PIV) have illustrated the role of velocity, instantaneous vortices, and key recirculation zones that are all critical to the combustor's operation. It was found that considerable differences exist between the iso-thermal and reacting flows, and between the instantaneous and mean flow fields. To image the flame, Planar Laser Induced Fluorescence (PLIF) of the formaldehyde radical was successfully utilized for the first time in a Jet-A flame. Parameters regarding the flame's location and structure have been obtained that assist in interpreting the velocity results. These results have also shown that some of the fuel injected from the main fuel injectors actually reacts in the diffusion flame of the pilot. The unstable operation of the combustor was studied in depth to obtain the stability limits of the combustor, behavior of the flame dynamics, and frequencies of the oscillations. Results from simultaneous pressure and high speed chemiluminescence images have shown that the low frequency dynamics can be characterized as flashback oscillations. The results have also shown that the stability of the combustor can be explained by simple and well established premixed flame stability mechanisms. This study has allowed the development of a model that describes the instability mechanism and accurately captures the frequencies of the oscillations. By demonstrating how these classical understandings can be applied to the extremely complicated flow within LPP gas turbine combustors, new insight has been provided that will aid in the development of the next generation of cleaner, more stable gas turbine combustors.

14 CFR 33.89 - Operation test.

Code of Federal Regulations, 2011 CFR

2011-01-01

..., acceleration, overspeeding, ignition, functioning of the propeller (if the engine is designated to operate with a propeller); (2) Compliance with the engine response requirements of § 33.73; and (3) The minimum... STANDARDS: AIRCRAFT ENGINES Block Tests; Turbine Aircraft Engines § 33.89 Operation test. (a) The operation...

14 CFR 33.89 - Operation test.

Code of Federal Regulations, 2012 CFR

2012-01-01

..., acceleration, overspeeding, ignition, functioning of the propeller (if the engine is designated to operate with a propeller); (2) Compliance with the engine response requirements of § 33.73; and (3) The minimum... STANDARDS: AIRCRAFT ENGINES Block Tests; Turbine Aircraft Engines § 33.89 Operation test. (a) The operation...

Task Management in the New ATLAS Production System

NASA Astrophysics Data System (ADS)

De, K.; Golubkov, D.; Klimentov, A.; Potekhin, M.; Vaniachine, A.; Atlas Collaboration

2014-06-01

This document describes the design of the new Production System of the ATLAS experiment at the LHC [1]. The Production System is the top level workflow manager which translates physicists' needs for production level processing and analysis into actual workflows executed across over a hundred Grid sites used globally by ATLAS. As the production workload increased in volume and complexity in recent years (the ATLAS production tasks count is above one million, with each task containing hundreds or thousands of jobs) there is a need to upgrade the Production System to meet the challenging requirements of the next LHC run while minimizing the operating costs. In the new design, the main subsystems are the Database Engine for Tasks (DEFT) and the Job Execution and Definition Interface (JEDI). Based on users' requests, DEFT manages inter-dependent groups of tasks (Meta-Tasks) and generates corresponding data processing workflows. The JEDI component then dynamically translates the task definitions from DEFT into actual workload jobs executed in the PanDA Workload Management System [2]. We present the requirements, design parameters, basics of the object model and concrete solutions utilized in building the new Production System and its components.

Low NO sub x heavy fuel combustor concept program. Phase 1A: Combustion technology generation coal gas fuels

NASA Technical Reports Server (NTRS)

Sherlock, T. P.

1982-01-01

Combustion tests of two scaled burners using actual coal gas from a 25 ton/day fluidized bed coal gasifier are described. The two combustor configurations studied were a ceramic lined, staged rich/lean burner and an integral, all metal multiannual swirl burner (MASB). The tests were conducted over a range of temperature and pressures representative of current industrial combustion turbine inlet conditions. Tests on the rich lean burner were conducted at three levels of product gas heating values: 104, 197 and 254 btu/scf. Corresponding levels of NOx emissions were 5, 20 and 70 ppmv. Nitrogen was added to the fuel in the form of ammonia, and conversion efficiencies of fuel nitrogen to NOx were on the order of 4 percent to 12 percent, which is somewhat lower than the 14 percent to 18 percent conversion efficiency when src-2 liquid fuel was used. The MASB was tested only on medium btu gas (220 to 270 btu/scf), and produced approximately 80 ppmv NOx at rated engine conditions. Both burners operated similarly on actual coal gas and erbs fuel, and all heating values tested can be successfully burned in current machines.

Monitoring based maintenance utilizing actual stress sensory technology

NASA Astrophysics Data System (ADS)

Sumitro, Sunaryo; Kurokawa, Shoji; Shimano, Keiji; Wang, Ming L.

2005-06-01

In recent years, many infrastructures have been deteriorating. In order to maintain sustainability of those infrastructures which have significant influence on social lifelines, economical and rational maintenance management should be carried out to evaluate the life cycle cost (LCC). The development of structural health monitoring systems, such as deriving evaluation techniques for the field structural condition of existing structures and identification techniques for the significant engineering properties of new structures, can be considered as the first step in resolving the above problem. New innovative evaluation methods need to be devised to identify the deterioration of infrastructures, e.g. steel tendons, cables in cable-stayed bridges and strands embedded in pre- or post-tensioned concrete structures. One of the possible solutions that show 'AtoE' characteristics, i.e., (a)ccuracy, (b)enefit, (c)ompendiousness, (d)urability and (e)ase of operation, elasto-magnetic (EM) actual stress sensory technology utilizing the sensitivity of incremental magnetic permeability to stress change, has been developed. Numerous verification tests on various steel materials have been conducted. By comparing with load cell, strain gage and other sensory technology measurement results, the actual stresses of steel tendons in a pre-stressed concrete structure at the following stages have been thoroughly investigated: (i) pre-stress change due to set-loss (anchorage slippage) at the tendon fixation stage; (ii) pre-stress change due to the tendon relaxation stage; (iii) concrete creep and shrinkage at the long term pre-stressing stage; (iv) pre-stress change in the cyclic fatigue loading stage; and (v) pre-stress change due to the re-pre-stress setting stage. As the result of this testing, it is confirmed that EM sensory technology enables one to measure actual stress in steel wire, strands and steel bars precisely without destroying the polyethylene covering sheath and enables one to provide adequate accuracy and reliability for monitoring actual stresses of those steel tendons during the life cycle of infrastructures. An example of a field application at a cable-stayed bridge is described.

Modeling Parasitic Energy Losses and the Impact of Advanced Tribological Concepts on Fuel Efficiency - Final CRADA Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fenske, George

2016-11-28

Our primary task for this project was to perform FMEP calculations for a broad range of parameters including engine type [spark ignition (SI) or compression ignition (CI)], engine size, engine mode (speed and load), lubricant viscosity, asperity friction, surface finish, oil type (mineral or synthetic), and additive (friction modifier), as discussed previously [1–3]. The actual analysis was limited to a large diesel engine and it included both load and speed dependencies as well as lubricant viscosity and speed.

Concurrently adjusting interrelated control parameters to achieve optimal engine performance

DOEpatents

Jiang, Li; Lee, Donghoon; Yilmaz, Hakan; Stefanopoulou, Anna

2015-12-01

Methods and systems for real-time engine control optimization are provided. A value of an engine performance variable is determined, a value of a first operating condition and a value of a second operating condition of a vehicle engine are detected, and initial values for a first engine control parameter and a second engine control parameter are determined based on the detected first operating condition and the detected second operating condition. The initial values for the first engine control parameter and the second engine control parameter are adjusted based on the determined value of the engine performance variable to cause the engine performance variable to approach a target engine performance variable. In order to cause the engine performance variable to approach the target engine performance variable, adjusting the initial value for the first engine control parameter necessitates a corresponding adjustment of the initial value for the second engine control parameter.

14 CFR 121.191 - Airplanes: Turbine engine powered: En route limitations: One engine inoperative.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Airplanes: Turbine engine powered: En route...: CERTIFICATION AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.191 Airplanes: Turbine engine powered: En route limitations: One...

14 CFR 121.193 - Airplanes: Turbine engine powered: En route limitations: Two engines inoperative.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Airplanes: Turbine engine powered: En route...: CERTIFICATION AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.193 Airplanes: Turbine engine powered: En route limitations: Two...

14 CFR 121.193 - Airplanes: Turbine engine powered: En route limitations: Two engines inoperative.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Airplanes: Turbine engine powered: En route...: CERTIFICATION AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.193 Airplanes: Turbine engine powered: En route limitations: Two...

14 CFR 121.191 - Airplanes: Turbine engine powered: En route limitations: One engine inoperative.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Airplanes: Turbine engine powered: En route...: CERTIFICATION AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.191 Airplanes: Turbine engine powered: En route limitations: One...

14 CFR 121.193 - Airplanes: Turbine engine powered: En route limitations: Two engines inoperative.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Airplanes: Turbine engine powered: En route...: CERTIFICATION AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.193 Airplanes: Turbine engine powered: En route limitations: Two...

14 CFR 121.191 - Airplanes: Turbine engine powered: En route limitations: One engine inoperative.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Airplanes: Turbine engine powered: En route...: CERTIFICATION AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.191 Airplanes: Turbine engine powered: En route limitations: One...

40 CFR 60.4204 - What emission standards must I meet for non-emergency engines if I am an owner or operator of a...

Code of Federal Regulations, 2011 CFR

2011-07-01

... non-emergency engines if I am an owner or operator of a stationary CI internal combustion engine? 60... Compression Ignition Internal Combustion Engines Emission Standards for Owners and Operators § 60.4204 What... internal combustion engine? (a) Owners and operators of pre-2007 model year non-emergency stationary CI ICE...

40 CFR 60.4204 - What emission standards must I meet for non-emergency engines if I am an owner or operator of a...

Code of Federal Regulations, 2013 CFR

2013-07-01

... non-emergency engines if I am an owner or operator of a stationary CI internal combustion engine? 60... Compression Ignition Internal Combustion Engines Emission Standards for Owners and Operators § 60.4204 What... internal combustion engine? (a) Owners and operators of pre-2007 model year non-emergency stationary CI ICE...

40 CFR 60.4204 - What emission standards must I meet for non-emergency engines if I am an owner or operator of a...

Code of Federal Regulations, 2014 CFR

2014-07-01

... non-emergency engines if I am an owner or operator of a stationary CI internal combustion engine? 60... Compression Ignition Internal Combustion Engines Emission Standards for Owners and Operators § 60.4204 What... internal combustion engine? (a) Owners and operators of pre-2007 model year non-emergency stationary CI ICE...

40 CFR 60.4204 - What emission standards must I meet for non-emergency engines if I am an owner or operator of a...

Code of Federal Regulations, 2012 CFR

2012-07-01

... non-emergency engines if I am an owner or operator of a stationary CI internal combustion engine? 60... Compression Ignition Internal Combustion Engines Emission Standards for Owners and Operators § 60.4204 What... internal combustion engine? (a) Owners and operators of pre-2007 model year non-emergency stationary CI ICE...

Theseus in Flight

NASA Technical Reports Server (NTRS)

1996-01-01

The twin pusher engines of the prototype Theseus research aircraft can be clearly seen in this photo of the aircraft during a 1996 research flight from the Dryden Flight Research Center, Edwards, California. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements. Dryden's Project Manager was John Del Frate.

Theseus in Flight

NASA Technical Reports Server (NTRS)

1996-01-01

The twin pusher propeller-driven engines of the Theseus research aircraft can be clearly seen in this photo, taken during a 1996 research flight at NASA's Dryden Flight Research Center, Edwards, California. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements. Dryden's Project Manager was John Del Frate.

Telemetry data via communications relay

NASA Astrophysics Data System (ADS)

Strock, O. J.; Witchey, Michael

This paper responds to a test range engineer's need to relay one or more channels of various types of telemetry data from a remotely-located receiving station to the central telemetry station at range headquarters for real-time processing and display. Several types of data are identified, and specific equipment and technology for multiplexing, transmission, and demultiplexing up to eight streams from a variety of sources is discussed. The widely-used T3 communications link, also known as DS-3, can relay data via satellite, microwave link, or other high-speed path at 44.736 megabits per second, of which about 95 percent can be actual telemetry data; other standard links operate at lower aggregate rates. Several links and rates are discussed, with emphasis in the high-rate T3 link.

Mach 0.3 Burner Rig Facility at the NASA Glenn Materials Research Laboratory

NASA Technical Reports Server (NTRS)

Fox, Dennis S.; Miller, Robert A.; Zhu, Dongming; Perez, Michael; Cuy, Michael D.; Robinson, R. Craig

2011-01-01

This Technical Memorandum presents the current capabilities of the state-of-the-art Mach 0.3 Burner Rig Facility. It is used for materials research including oxidation, corrosion, erosion and impact. Consisting of seven computer controlled jet-fueled combustors in individual test cells, these relatively small rigs burn just 2 to 3 gal of jet fuel per hour. The rigs are used as an efficient means of subjecting potential aircraft engine/airframe advanced materials to the high temperatures, high velocities and thermal cycling closely approximating actual operating environments. Materials of various geometries and compositions can be evaluated at temperatures from 700 to 2400 F. Tests are conducted not only on bare superalloys and ceramics, but also to study the behavior and durability of protective coatings applied to those materials.

A cost analysis for the implementation of commonality in the family of commuter airplanes, revised

NASA Technical Reports Server (NTRS)

Creighton, Tom; Haddad, Rafael; Hendrich, Louis; Hensley, Doug; Morgan, Louise; Russell, Mark; Swift, Jerry

1987-01-01

The acquisition costs determined for the NASA family of commute airplanes are presented. The costs of the baseline designs are presented along with the calculated savings due to the commonality in the family. A sensitivity study is also presented to show the major drivers in the acquisition cost calculations. The baseline costs are calculated with the Nicolai method. A comparison is presented of the estimated costs for the commuter family with the actual price for existing commuters. The cost calculations for the engines and counter-rotating propellers are reported. The effects of commonality on acquisition costs are calculated. The sensitivity calculations of the cost to various costing parameters are shown. The calculations for the direct operating costs, with and without commonality are presented.

47 CFR 36.123 - Operator systems equipment-Category 1.

Code of Federal Regulations, 2014 CFR

2014-10-01

... apportioned on the basis of the relative processor real time (i.e., actual seconds) required to process TSPS... relative processor real time (i.e., actual seconds) for the entire TSPS complex. [52 FR 17229, May 6, 1987... 47 Telecommunication 2 2014-10-01 2014-10-01 false Operator systems equipment-Category 1. 36.123...

47 CFR 36.123 - Operator systems equipment-Category 1.

Code of Federal Regulations, 2013 CFR

2013-10-01

... apportioned on the basis of the relative processor real time (i.e., actual seconds) required to process TSPS... relative processor real time (i.e., actual seconds) for the entire TSPS complex. [52 FR 17229, May 6, 1987... 47 Telecommunication 2 2013-10-01 2013-10-01 false Operator systems equipment-Category 1. 36.123...

47 CFR 36.123 - Operator systems equipment-Category 1.

Code of Federal Regulations, 2012 CFR

2012-10-01

... apportioned on the basis of the relative processor real time (i.e., actual seconds) required to process TSPS... relative processor real time (i.e., actual seconds) for the entire TSPS complex. [52 FR 17229, May 6, 1987... 47 Telecommunication 2 2012-10-01 2012-10-01 false Operator systems equipment-Category 1. 36.123...

47 CFR 36.123 - Operator systems equipment-Category 1.

Code of Federal Regulations, 2011 CFR

2011-10-01

... apportioned on the basis of the relative processor real time (i.e., actual seconds) required to process TSPS... relative processor real time (i.e., actual seconds) for the entire TSPS complex. [52 FR 17229, May 6, 1987... 47 Telecommunication 2 2011-10-01 2011-10-01 false Operator systems equipment-Category 1. 36.123...

Estimating C-17 Aircrew Seasoning Given a Prediction of Flying Austerity

DTIC Science & Technology

2014-06-01

mission classification, operating organization, operating squadron, actual departure time (in Zulu ), actual arrival time (in Zulu ), and flight time in...zero. The horizontal axis is the time axis and is in Julian day units starting with January 1, 2013 and terminates at 2359 Zulu on June 30th 2013

47 CFR 36.123 - Operator systems equipment-Category 1.

Code of Federal Regulations, 2010 CFR

2010-10-01

... apportioned on the basis of the relative processor real time (i.e., actual seconds) required to process TSPS... relative processor real time (i.e., actual seconds) for the entire TSPS complex. [52 FR 17229, May 6, 1987... 47 Telecommunication 2 2010-10-01 2010-10-01 false Operator systems equipment-Category 1. 36.123...

Flexible fabrication systems in practice - Investigation of the operational behavior

NASA Astrophysics Data System (ADS)

Buedenbender, Winfried; Scheller, Thomas

1987-10-01

The operational behavior of flexible fabrication systems (FSS) is analyzed using two actual cases. It is found that fabrication using FSS has attained a certain standard. The technical availability and the actual use of FSS depends to a large extent on the qualifications and performance of the service and maintenance personnel.

12 CFR 1070.22 - Fees for processing requests for CFPB records.

Code of Federal Regulations, 2013 CFR

2013-01-01

... CFPB shall charge the requester for the actual direct cost of the search, including computer search time, runs, and the operator's salary. The fee for computer output will be the actual direct cost. For... and the cost of operating the computer to process a request) equals the equivalent dollar amount of...

Engine control techniques to account for fuel effects

DOEpatents

Kumar, Shankar; Frazier, Timothy R.; Stanton, Donald W.; Xu, Yi; Bunting, Bruce G.; Wolf, Leslie R.

2014-08-26

A technique for engine control to account for fuel effects including providing an internal combustion engine and a controller to regulate operation thereof, the engine being operable to combust a fuel to produce an exhaust gas; establishing a plurality of fuel property inputs; establishing a plurality of engine performance inputs; generating engine control information as a function of the fuel property inputs and the engine performance inputs; and accessing the engine control information with the controller to regulate at least one engine operating parameter.

Theseus in Flight

NASA Technical Reports Server (NTRS)

1996-01-01

The Theseus research aircraft in flight over Rogers Dry Lake, Edwards, California, during a 1996 research flight. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements. Dryden's Project Manager was John Del Frate.

Theseus Assembly Sequence #1

NASA Technical Reports Server (NTRS)

1996-01-01

The Theseus prototype research aircraft being assembled at NASA's Dryden Flight Research Center, Edwards, California, in May of 1996. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements. Dryden's Project Manager was John Del Frate.

Theseus Assembly Sequence #3

NASA Technical Reports Server (NTRS)

1996-01-01

The Theseus prototype research aircraft being assembled at NASA's Dryden Flight Research Center, Edwards, California, in May of 1996. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements. Dryden's Project Manager was John Del Frate.

14 CFR 121.565 - Engine inoperative: Landing; reporting.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Engine inoperative: Landing; reporting. 121... OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.565 Engine... engine fails or whenever an engine is shutdown to prevent possible damage, the pilot in command must land...

14 CFR 23.65 - Climb: All engines operating.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Climb: All engines operating. 23.65 Section... Climb: All engines operating. (a) Each normal, utility, and acrobatic category reciprocating engine... than maximum continuous power on each engine; (2) The landing gear retracted; (3) The wing flaps in the...

14 CFR 121.565 - Engine inoperative: Landing; reporting.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Engine inoperative: Landing; reporting. 121... OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.565 Engine... engine fails or whenever an engine is shutdown to prevent possible damage, the pilot in command must land...

14 CFR 121.565 - Engine inoperative: Landing; reporting.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Engine inoperative: Landing; reporting. 121... OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.565 Engine... engine fails or whenever an engine is shutdown to prevent possible damage, the pilot in command must land...

14 CFR 23.65 - Climb: All engines operating.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Climb: All engines operating. 23.65 Section... Climb: All engines operating. (a) Each normal, utility, and acrobatic category reciprocating engine... than maximum continuous power on each engine; (2) The landing gear retracted; (3) The wing flaps in the...

14 CFR 121.565 - Engine inoperative: Landing; reporting.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Engine inoperative: Landing; reporting. 121... OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.565 Engine... engine fails or whenever an engine is shutdown to prevent possible damage, the pilot in command must land...

University of Colorado CubeSat Student Projects as Successful Model for Teaching Students about Engineering Practices

NASA Astrophysics Data System (ADS)

Palo, S. E.; Li, X.; Woods, T. N.; Kohnert, R.

2014-12-01

There is a long history of cooperation between students at the University of Colorado, Boulder and professional engineers and scientists at LASP, which has led to many successful space missions with direct student involvement. The recent student-led missions include the Student Nitric Oxide Explorer (SNOE, 1998 - 2002), the Student Dust Counter (SDC) on New Horizons (2006 - present), the Colorado Student Space Weather Experiment (CSSWE), being a very successful NSF CubeSat that launched in September 2012, and the NASA Miniature X-ray Solar Spectrometer (MinXSS) CubeSat (launch will be in early 2015). Students are involved in all aspects of the design, and they experience the full scope of the mission process from concept, to fabrication and test, and mission operations. A significant part of the student involvement in the CubeSat projects is gained by using the CubeSat development as a focal point for an existing two-semester course sequence in CU's Aerospace Engineering Sciences (AES) Department: the Space Hardware Design section of Graduate Projects I & II (ASEN 5018 & ASEN 6028). The goal of these courses is to teach graduate students how to design and build systems using a requirement-based approach and fundamental systems engineering practices. The two-semester sequence takes teams of about 15 students from requirements definition and preliminary design through manufacturing, integration, and testing. In addition to the design process, students learn key professional skills such as working effectively in groups, finding solutions to open-ended problems, and actually building a system to their own set of specifications. The partnership between AES and LASP allows us to include engineering professionals in the mix, thus more effectively training science and engineering students for future roles in the civilian or commercial space industry. The mentoring process with LASP engineers helps to mitigate risk of the inexperience of the students and ensures consistent system engineer oversight for the multi-year CubeSat programs.

14 CFR 33.51 - Operation test.

Code of Federal Regulations, 2012 CFR

2012-01-01

... STANDARDS: AIRCRAFT ENGINES Block Tests; Reciprocating Aircraft Engines § 33.51 Operation test. The... characteristics, starting, idling, acceleration, overspeeding, functioning of propeller and ignition, and any other operational characteristic of the engine. If the engine incorporates a multispeed supercharger...

14 CFR 33.51 - Operation test.

Code of Federal Regulations, 2011 CFR

2011-01-01

... STANDARDS: AIRCRAFT ENGINES Block Tests; Reciprocating Aircraft Engines § 33.51 Operation test. The... characteristics, starting, idling, acceleration, overspeeding, functioning of propeller and ignition, and any other operational characteristic of the engine. If the engine incorporates a multispeed supercharger...

Accessible engineering drawings for visually impaired machine operators.

PubMed

Ramteke, Deepak; Kansal, Gayatri; Madhab, Benu

2014-01-01

An engineering drawing provides manufacturing information to a machine operator. An operator plans and executes machining operations based on this information. A visually impaired (VI) operator does not have direct access to the drawings. Drawing information is provided to them verbally or by using sample parts. Both methods have limitations that affect the quality of output. Use of engineering drawings is a standard practice for every industry; this hampers employment of a VI operator. Accessible engineering drawings are required to increase both independence, as well as, employability of VI operators. Today, Computer Aided Design (CAD) software is used for making engineering drawings, which are saved in CAD files. Required information is extracted from the CAD files and converted into Braille or voice. The authors of this article propose a method to make engineering drawings information directly accessible to a VI operator.

Fuel quantity modulation in pilot ignited engines

DOEpatents

May, Andrew

2006-05-16

An engine system includes a first fuel regulator adapted to control an amount of a first fuel supplied to the engine, a second fuel regulator adapted to control an amount of a second fuel supplied to the engine concurrently with the first fuel being supplied to the engine, and a controller coupled to at least the second fuel regulator. The controller is adapted to determine the amount of the second fuel supplied to the engine in a relationship to the amount of the first fuel supplied to the engine to operate in igniting the first fuel at a specified time in steady state engine operation and adapted to determine the amount of the second fuel supplied to the engine in a manner different from the relationship at steady state engine operation in transient engine operation.

Metadata Effectiveness in Internet Discovery: An Analysis of Digital Collection Metadata Elements and Internet Search Engine Keywords

ERIC Educational Resources Information Center

Yang, Le

2016-01-01

This study analyzed digital item metadata and keywords from Internet search engines to learn what metadata elements actually facilitate discovery of digital collections through Internet keyword searching and how significantly each metadata element affects the discovery of items in a digital repository. The study found that keywords from Internet…

40 CFR 51.118 - Stack height provisions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... exceeds good engineering practice or by any other dispersion technique, except as provided in § 51.118(b... based on a good engineering practice stack height that exceeds the height allowed by § 51.100(ii) (1) or... actual stack height of any source. (b) The provisions of § 51.118(a) shall not apply to (1) stack heights...

Overview of the National Timber Bridge Inspection Study

Treesearch

James P. Wacker; Brian K. Brashaw; Frank Jalinoos

2013-01-01

As many engineers begin to implement life cycle cost analyses within the preliminary bridge design phase, there is a significant need for more reliable data on the expected service life of highway bridges. Many claims are being made about the expected longevity of concrete and steel bridges, but few are based on actual performance data. Because engineers are least...

Method for operating a spark-ignition, direct-injection internal combustion engine

DOEpatents

Narayanaswamy, Kushal; Koch, Calvin K.; Najt, Paul M.; Szekely, Jr., Gerald A.; Toner, Joel G.

2015-06-02

A spark-ignition, direct-injection internal combustion engine is coupled to an exhaust aftertreatment system including a three-way catalytic converter upstream of an NH3-SCR catalyst. A method for operating the engine includes operating the engine in a fuel cutoff mode and coincidentally executing a second fuel injection control scheme upon detecting an engine load that permits operation in the fuel cutoff mode.

Quantitative Ultrasonic Evaluation of Mechanical Properties of Engineering Materials

NASA Technical Reports Server (NTRS)

Vary, A.

1978-01-01

Progress in the application of ultrasonic techniques to nondestructive measurement of mechanical strength of engineering materials is reviewed. A dormant concept in nondestructive evaluation (NDE) is invoked. The availability of ultrasonic methods that can be applied to actual parts to assess their potential susceptibility to failure under design conditions is discussed. It was shown that ultrasonic methods yield measurements of elastic moduli, microstructure, hardness, fracture toughness, tensile strength, yield strength, and shear strength for a wide range of materials (including many types of metals, ceramics, and fiber composites). It was also indicated that although most of these methods were shown feasible in laboratory studies, more work is needed before they can be used on actual parts in processing, assembly, inspection, and maintenance lines.

General airplane performance

NASA Technical Reports Server (NTRS)

Rockfeller, W C

1939-01-01

Equations have been developed for the analysis of the performance of the ideal airplane, leading to an approximate physical interpretation of the performance problem. The basic sea-level airplane parameters have been generalized to altitude parameters and a new parameter has been introduced and physically interpreted. The performance analysis for actual airplanes has been obtained in terms of the equivalent ideal airplane in order that the charts developed for use in practical calculations will for the most part apply to any type of engine-propeller combination and system of control, the only additional material required consisting of the actual engine and propeller curves for propulsion unit. Finally, a more exact method for the calculation of the climb characteristics for the constant-speed controllable propeller is presented in the appendix.

Establishment of Kansei Database and Application to Design for Consensus Building

NASA Astrophysics Data System (ADS)

Yasuda, Keiichi; Shiraki, Wataru

Reflecting the recent social background where the importance of bridge landscape design is recognized and the new business style of citizen-involved infrastructure development has started, there has been a growing need of design where aesthetic feeling of actual users is reflected. In this research, a focus has been placed on the Kansei engineering technique where users' needs are reflected on product development. A questionnaire survey has been conducted for bridge engineers who are most intensively involved in design work and students as actual users. The result was analyzed by factor analysis and the Hayashi's quantification methods (category I). A tool required at consensus-building occasions has been created to change design elements and display accompanying evaluation difference while using the Kansei database.

49 CFR 236.1047 - Training specific to locomotive engineers and other operating personnel.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Training specific to locomotive engineers and... engineers and other operating personnel. (a) Operating personnel. Training provided under this subpart for any locomotive engineer or other person who participates in the operation of a train in train control...

49 CFR 236.1047 - Training specific to locomotive engineers and other operating personnel.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Training specific to locomotive engineers and... engineers and other operating personnel. (a) Operating personnel. Training provided under this subpart for any locomotive engineer or other person who participates in the operation of a train in train control...

49 CFR 236.1047 - Training specific to locomotive engineers and other operating personnel.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Training specific to locomotive engineers and... engineers and other operating personnel. (a) Operating personnel. Training provided under this subpart for any locomotive engineer or other person who participates in the operation of a train in train control...

49 CFR 236.1047 - Training specific to locomotive engineers and other operating personnel.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Training specific to locomotive engineers and... engineers and other operating personnel. (a) Operating personnel. Training provided under this subpart for any locomotive engineer or other person who participates in the operation of a train in train control...

Predictors of obesity in Michigan Operating Engineers.

PubMed

Duffy, Sonia A; Cohen, Kathleen A; Choi, Seung Hee; McCullagh, Marjorie C; Noonan, Devon

2012-06-01

Blue collar workers are at risk for obesity. Little is known about obesity in Operating Engineers, a group of blue collar workers, who operate heavy earth-moving equipment in road building and construction. Therefore, 498 Operating Engineers in Michigan were recruited to participate in a cross-sectional survey to determine variables related to obesity in this group. Bivariate and multivariate analyses were conducted to determine personal, psychological, and behavioral factors predicting obesity. Approximately 45% of the Operating Engineers screened positive for obesity, and another 40% were overweight. Multivariate analysis revealed that younger age, male sex, higher numbers of self-reported co-morbidities, not smoking, and low physical activity levels were significantly associated with obesity among Operating Engineers. Operating Engineers are significantly at risk for obesity, and workplace interventions are needed to address this problem.

Intelligent systems approach for automated identification of individual control behavior of a human operator

NASA Astrophysics Data System (ADS)

Zaychik, Kirill B.

Acceptable results have been obtained using conventional techniques to model the generic human operator's control behavior. However, little research has been done in an attempt to identify an individual based on his/her control behavior. The main hypothesis investigated in this dissertation is that different operators exhibit different control behavior when performing a given control task. Furthermore, inter-person differences are manifested in the amplitude and frequency content of the non-linear component of the control behavior. Two enhancements to the existing models of the human operator, which allow personalization of the modeled control behavior, are presented in this dissertation. One of the proposed enhancements accounts for the "testing" control signals, which are introduced by an operator for more accurate control of the system and/or to adjust his/her control strategy. Such enhancement uses the Artificial Neural Network (ANN), which can be fine-tuned to model the "testing" control behavior of a given individual. The other model enhancement took the form of an equiripple filter (EF), which conditions the power spectrum of the control signal before it is passed through the plant dynamics block. The filter design technique uses Parks-McClellan algorithm, which allows parameterization of the desired levels of power at certain frequencies. A novel automated parameter identification technique (APID) was developed to facilitate the identification process of the parameters of the selected models of the human operator. APID utilizes a Genetic Algorithm (GA) based optimization engine called the Bit-climbing Algorithm (BCA). Proposed model enhancements were validated using the experimental data obtained at three different sources: the Manual Control Laboratory software experiments, Unmanned Aerial Vehicle simulation, and NASA Langley Research Center Visual Motion Simulator studies. Validation analysis involves comparison of the actual and simulated control activity signals. Validation criteria used in this dissertation is based on comparing Power Spectral Densities of the control signals against that of the Precision model of the human operator. This dissertation also addresses the issue of applying the proposed human operator model augmentation to evaluate the effectiveness of the motion feedback when simulating the actual pilot control behavior in a flight simulator. The proposed modeling methodology allows for quantitative assessments and prediction of the need for platform motion, while performing aircraft/pilot simulation studies.

Status of Electrical Actuator Applications

NASA Technical Reports Server (NTRS)

Roth, Mary Ellen; Taylor, Linda M.; Hansen, Irving G.

1996-01-01

An ever increasing number of actuation functions historically performed by hydraulics or pneumatics are being accomplished by electric actuation. If 'end to end' systems are considered, electric actuators (EA's) are potentially lighter and more efficient. In general, system redundancies may be more easily implemented and operationally monitored. Typically, electrical components exhibit longer mean times to failure and projected lifetime costs of EA's are potentially much lower than those of other options. EA's have certain characteristics which must be considered in their application. The actual mechanical loadings must be established, for the more easily controlled EA may be operated much closer to its full capabilities. At higher rates of motion, EA's are operating as constant power devices. Therefore, it may be possible to start a movement that can not be stopped. The incorporation of high power electronics into remote locations introduces new concerns of EMI and thermal control. It is the management of these and other characteristics that forms the engineering design challenges. Work is currently in progress on EA's for aircraft and expendable launch vehicles. These applications span from ten to 40+ horsepower. The systematics and status of these actuators will be reported along with current technical trends in this area.

Vulnerability of manned spacecraft to crew loss from orbital debris penetration

NASA Technical Reports Server (NTRS)

Williamsen, J. E.

1994-01-01

Orbital debris growth threatens the survival of spacecraft systems from impact-induced failures. Whereas the probability of debris impact and spacecraft penetration may currently be calculated, another parameter of great interest to safety engineers is the probability that debris penetration will cause actual spacecraft or crew loss. Quantifying the likelihood of crew loss following a penetration allows spacecraft designers to identify those design features and crew operational protocols that offer the highest improvement in crew safety for available resources. Within this study, a manned spacecraft crew survivability (MSCSurv) computer model is developed that quantifies the conditional probability of losing one or more crew members, P(sub loss/pen), following the remote likelihood of an orbital debris penetration into an eight module space station. Contributions to P(sub loss/pen) are quantified from three significant penetration-induced hazards: pressure wall rupture (explosive decompression), fragment-induced injury, and 'slow' depressurization. Sensitivity analyses are performed using alternate assumptions for hazard-generating functions, crew vulnerability thresholds, and selected spacecraft design and crew operations parameters. These results are then used to recommend modifications to the spacecraft design and expected crew operations that quantitatively increase crew safety from orbital debris impacts.

Interstage Flammability Analysis Approach

NASA Technical Reports Server (NTRS)

Little, Jeffrey K.; Eppard, William M.

2011-01-01

The Interstage of the Ares I launch platform houses several key components which are on standby during First Stage operation: the Reaction Control System (ReCS), the Upper Stage (US) Thrust Vector Control (TVC) and the J-2X with the Main Propulsion System (MPS) propellant feed system. Therefore potentially dangerous leaks of propellants could develop. The Interstage leaks analysis addresses the concerns of localized mixing of hydrogen and oxygen gases to produce deflagration zones in the Interstage of the Ares I launch vehicle during First Stage operation. This report details the approach taken to accomplish the analysis. Specified leakage profiles and actual flammability results are not presented due to proprietary and security restrictions. The interior volume formed by the Interstage walls, bounding interfaces with the Upper and First Stages, and surrounding the J2-X engine was modeled using Loci-CHEM to assess the potential for flammable gas mixtures to develop during First Stage operations. The transient analysis included a derived flammability indicator based on mixture ratios to maintain achievable simulation times. Validation of results was based on a comparison to Interstage pressure profiles outlined in prior NASA studies. The approach proved useful in the bounding of flammability risk in supporting program hazard reviews.

Landsat-7 Simulation and Testing Environments

NASA Technical Reports Server (NTRS)

Holmes, E.; Ha, K.; Hawkins, K.; Lombardo, J.; Ram, M.; Sabelhaus, P.; Scott, S.; Phillips, R.

1999-01-01

A spacecraft Attitude Control and Determination Subsystem (ACDS) is heavily dependent upon simulation throughout its entire development, implementation and ground test cycle. Engineering simulation tools are typically developed to design and analyze control systems to validate the design and software simulation tools are required to qualify the flight software. However, the need for simulation does not end here. Operating the ACDS of a spacecraft on the ground requires the simulation of spacecraft dynamics, disturbance modeling and celestial body motion. Sensor data must also be simulated and substituted for actual sensor data on the ground so that the spacecraft will respond by sending commands to the actuators as they will on orbit. And finally, the simulators is the primary training tool and test-bed for the Flight Operations Team. In this paper various ACDS simulation, developed for or used by the Landsat 7 project will be described. The paper will include a description of each tool, its unique attributes, and its role in the overall development and testing of the ACDS. Finally, a section is included which discusses how the coordinated use of these simulation tools can maximize the probability of uncovering software, hardware and operations errors during the ground test process.

Computer Design Technology of the Small Thrust Rocket Engines Using CAE / CAD Systems

NASA Astrophysics Data System (ADS)

Ryzhkov, V.; Lapshin, E.

2018-01-01

The paper presents an algorithm for designing liquid small thrust rocket engine, the process of which consists of five aggregated stages with feedback. Three stages of the algorithm provide engineering support for design, and two stages - the actual engine design. A distinctive feature of the proposed approach is a deep study of the main technical solutions at the stage of engineering analysis and interaction with the created knowledge (data) base, which accelerates the process and provides enhanced design quality. The using multifunctional graphic package Siemens NX allows to obtain the final product -rocket engine and a set of design documentation in a fairly short time; the engine design does not require a long experimental development.

14 CFR 121.181 - Airplanes: Reciprocating engine-powered: En route limitations: One engine inoperative.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Airplanes: Reciprocating engine-powered: En... OPERATIONS Airplane Performance Operating Limitations § 121.181 Airplanes: Reciprocating engine-powered: En... person operating a reciprocating engine powered airplane may take off that airplane at a weight, allowing...

14 CFR 121.181 - Airplanes: Reciprocating engine-powered: En route limitations: One engine inoperative.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Airplanes: Reciprocating engine-powered: En... OPERATIONS Airplane Performance Operating Limitations § 121.181 Airplanes: Reciprocating engine-powered: En... person operating a reciprocating engine powered airplane may take off that airplane at a weight, allowing...

14 CFR 121.181 - Airplanes: Reciprocating engine-powered: En route limitations: One engine inoperative.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Airplanes: Reciprocating engine-powered: En... OPERATIONS Airplane Performance Operating Limitations § 121.181 Airplanes: Reciprocating engine-powered: En... person operating a reciprocating engine powered airplane may take off that airplane at a weight, allowing...

14 CFR 121.181 - Airplanes: Reciprocating engine-powered: En route limitations: One engine inoperative.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Airplanes: Reciprocating engine-powered: En... OPERATIONS Airplane Performance Operating Limitations § 121.181 Airplanes: Reciprocating engine-powered: En... person operating a reciprocating engine powered airplane may take off that airplane at a weight, allowing...

14 CFR 121.181 - Airplanes: Reciprocating engine-powered: En route limitations: One engine inoperative.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Airplanes: Reciprocating engine-powered: En... OPERATIONS Airplane Performance Operating Limitations § 121.181 Airplanes: Reciprocating engine-powered: En... person operating a reciprocating engine powered airplane may take off that airplane at a weight, allowing...

Study of Bird Ingestions into Small Inlet Area Aircraft Turbine Engines

DTIC Science & Technology

1990-12-01

engines (ALF502, TFE731 , TPE331, and JTI5D) included in the study. This includes 24 months of operations for the first three engines and 12 months of...through the National Teclical Bird Ingestion- TFE731 Information Service, Springfield, 4 Tuibine Engine,’ TPt331 Virginia 22161 Turbofan Engine...ALF502 Engine 7 2.2 Operations, TFE731 Engine 8 2.3 Operations, TPE331 Engine 9 3.1 Distribution of Bird Weights 13 3.2 Aircraft Ingestions by Month

Design of a microprocessor-based Control, Interface and Monitoring (CIM unit for turbine engine controls research

NASA Technical Reports Server (NTRS)

Delaat, J. C.; Soeder, J. F.

1983-01-01

High speed minicomputers were used in the past to implement advanced digital control algorithms for turbine engines. These minicomputers are typically large and expensive. It is desirable for a number of reasons to use microprocessor-based systems for future controls research. They are relatively compact, inexpensive, and are representative of the hardware that would be used for actual engine-mounted controls. The Control, Interface, and Monitoring Unit (CIM) contains a microprocessor-based controls computer, necessary interface hardware and a system to monitor while it is running an engine. It is presently being used to evaluate an advanced turbofan engine control algorithm.

Engine starting and stopping

NASA Astrophysics Data System (ADS)

Curnock, Barry

Different starter systems for jet engines are discussed: electric, cartridge, iso-propyl-nitrate, air, gas turbine, and hydraulic. The fuel system, ignition system, air flow control system, and actual starting mechanism of an air starter motor system are considered. The variation of engine parameters throughout a typical starting sequence are described, with reference to examples for an RB211-535 engine. Physical constraints on engine starting are considered: rotating stall, light up, the window between hang and stall, hang, compressor stall, and the effects of ambient conditions. The following are also discussed: contractual and airworthiness requirements; windmilling; inflight relighting; afterburning light up; combustion stability; and broken shafts. Graphics illustrating the above are presented.

FAA Rotorcraft Research, Engineering, and Development Bibliography, 1962-1988. Supplement

DTIC Science & Technology

1989-03-01

fires, the aircraft engine was the major fire origin for twin- and single- engine air - craft. Only in single- engine aircraft was the instrument panel a...Certification Issues. The topics of Operational Requirements, Procedures, Air - worthiness and Engineering Capabilities are discussed. Volume II presents the...Issues. The topics of Operational Requirements, Procedures, Air - worthiness and Engineering Capabilities are discussed. Volume II presents the operator

25 CFR 39.201 - Does ISEF reflect the actual cost of school operations?

Code of Federal Regulations, 2013 CFR

2013-04-01

... 25 Indians 1 2013-04-01 2013-04-01 false Does ISEF reflect the actual cost of school operations? 39.201 Section 39.201 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR EDUCATION THE... relative distribution of available funds at the local school level by comparison with all other Bureau...

25 CFR 39.201 - Does ISEF reflect the actual cost of school operations?

Code of Federal Regulations, 2014 CFR

2014-04-01

... 25 Indians 1 2014-04-01 2014-04-01 false Does ISEF reflect the actual cost of school operations? 39.201 Section 39.201 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR EDUCATION THE... relative distribution of available funds at the local school level by comparison with all other Bureau...

25 CFR 39.201 - Does ISEF reflect the actual cost of school operations?

Code of Federal Regulations, 2012 CFR

2012-04-01

... 25 Indians 1 2012-04-01 2011-04-01 true Does ISEF reflect the actual cost of school operations? 39.201 Section 39.201 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR EDUCATION THE INDIAN... distribution of available funds at the local school level by comparison with all other Bureau-funded schools. ...

25 CFR 39.201 - Does ISEF reflect the actual cost of school operations?

Code of Federal Regulations, 2011 CFR

2011-04-01

... 25 Indians 1 2011-04-01 2011-04-01 false Does ISEF reflect the actual cost of school operations? 39.201 Section 39.201 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR EDUCATION THE... relative distribution of available funds at the local school level by comparison with all other Bureau...

Segmented ion thruster

NASA Technical Reports Server (NTRS)

Brophy, John R. (Inventor)

1993-01-01

Apparatus and methods for large-area, high-power ion engines comprise dividing a single engine into a combination of smaller discharge chambers (or segments) configured to operate as a single large-area engine. This segmented ion thruster (SIT) approach enables the development of 100-kW class argon ion engines for operation at a specific impulse of 10,000 s. A combination of six 30-cm diameter ion chambers operating as a single engine can process over 100 kW. Such a segmented ion engine can be operated from a single power processor unit.

Engineering Psychology Handbook AY 2012 - 2013

DTIC Science & Technology

2012-08-01

in the department Awards Room. 2001 Honoree: Anastasia Piotrowski 2002 Honoree: Jennifer Smith 2003 Honoree: Joseph Mitek 2004 Honoree: Eric...MAJ Jennifer Bower jennifer.bower@us.army.mil COL Joseph P. DeAntona joseph.deantona@us.army.mil Dr. Gina Kolisinski MAJ Silas Martinez...of the document that you actually read (e.g., “ Craik and Tulving (as cited in Galotti, 1994) found that . . .”). Only the work that you actually

[Simulation and Design of Infant Incubator Assembly Line].

PubMed

Ke, Huqi; Hu, Xiaoyong; Ge, Xia; Hu, Yanhai; Chen, Zaihong

2015-11-01

According to current assembly situation of infant incubator in company A, basic industrial engineering means such as time study was used to analyze the actual products assembly production and an assembly line was designed. The assembly line was modeled and simulated with software Flexsim. The problem of the assembly line was found by comparing simulation result and actual data, then through optimization to obtain high efficiency assembly line.

14 CFR 23.777 - Cockpit controls.

Code of Federal Regulations, 2013 CFR

2013-01-01

... powerplant controls for each engine must be located to prevent confusion as to the engines they control. (1... engines(s) and the right control(s) operates the right engine(s). (2) On twin-engine airplanes with front and rear engine locations (tandem), the left powerplant controls must operate the front engine and the...

14 CFR 23.777 - Cockpit controls.

Code of Federal Regulations, 2014 CFR

2014-01-01

... powerplant controls for each engine must be located to prevent confusion as to the engines they control. (1... engines(s) and the right control(s) operates the right engine(s). (2) On twin-engine airplanes with front and rear engine locations (tandem), the left powerplant controls must operate the front engine and the...

Hayabusa Reentry and Recovery of Its Capsule -Quick Report

NASA Astrophysics Data System (ADS)

Kawaguchi, Junichiro; Yoshikawa, Makoto; Kuninaka, Hitoshi

The Hayabusa spacecraft successfully returned to the Earth and re-entered into the atmosphere for sample recovery after also the successful touching-downs to NEO Itokawa in 2005. The reentry occurred on June 13th, and took place in Woomera Prohibited Area (WPA) of Australia. This paper presents how the reentry and recovery operations were performed, and also reports the current status about the sample curation activity. The Hayabusa mission aims at demonstrating key technologies requisite for future real Sample and Return missions. However, the spacecraft adopted the actual Sample and Return flight sequence and was designed to make a world's first round trip to an extra terrestrial object with touching-down and lifting-off. It is the spacecraft propelled by the ion engines aboard for interplanetary cruise. The Hayabusa spacecraft launched in May of 2003 reached NEO Itokawa in September of 2005 via Earth gravity assist in May of 2004. It stayed there for about two and a half months, and performed detailed scientific observation and mapping and determination of the shape. In November of 2005, the spacecraft made two touching-downs and lifting-offs having attempted collection of surface sample. At the second opportunity, the spacecraft directed shooting a projectile. But, due to the programming problem, presumably the projectile was not shot. However, the spacecraft may have captured some small amount of sample particles in a catcher aboard, when the spacecraft made actual touches down to the surface. The spacecraft suffered from fuel leak in December of 2005, and the communication resumed after seven weeks of hiatus. And the ion engines all faced their life by November of 2009, and the project team devised an alternative drive configuration and successfully coped with the difficulty. Despite many hardships, the spacecraft has been operated for return cruise, and it made a reentry for sample recovery this June. The sample catcher was retrieved at WPA and transported back to the curation facility of JAXA. Currently the curators have examined analyzed the catcher recovered. This presentation quickly reports recent status of the spacecraft, capsule and sample analysis.

Enhanced Engine Performance During Emergency Operation Using a Model-Based Engine Control Architecture

NASA Technical Reports Server (NTRS)

Csank, Jeffrey T.; Connolly, Joseph W.

2016-01-01

This paper discusses the design and application of model-based engine control (MBEC) for use during emergency operation of the aircraft. The MBEC methodology is applied to the Commercial Modular Aero-Propulsion System Simulation 40k (CMAPSS40k) and features an optimal tuner Kalman Filter (OTKF) to estimate unmeasured engine parameters, which can then be used for control. During an emergency scenario, normally-conservative engine operating limits may be relaxed to increase the performance of the engine and overall survivability of the aircraft; this comes at the cost of additional risk of an engine failure. The MBEC architecture offers the advantage of estimating key engine parameters that are not directly measureable. Estimating the unknown parameters allows for tighter control over these parameters, and on the level of risk the engine will operate at. This will allow the engine to achieve better performance than possible when operating to more conservative limits on a related, measurable parameter.

Enhanced Engine Performance During Emergency Operation Using a Model-Based Engine Control Architecture

NASA Technical Reports Server (NTRS)

Csank, Jeffrey T.; Connolly, Joseph W.

2015-01-01

This paper discusses the design and application of model-based engine control (MBEC) for use during emergency operation of the aircraft. The MBEC methodology is applied to the Commercial Modular Aero-Propulsion System Simulation 40,000 (CMAPSS40,000) and features an optimal tuner Kalman Filter (OTKF) to estimate unmeasured engine parameters, which can then be used for control. During an emergency scenario, normally-conservative engine operating limits may be relaxed to increase the performance of the engine and overall survivability of the aircraft; this comes at the cost of additional risk of an engine failure. The MBEC architecture offers the advantage of estimating key engine parameters that are not directly measureable. Estimating the unknown parameters allows for tighter control over these parameters, and on the level of risk the engine will operate at. This will allow the engine to achieve better performance than possible when operating to more conservative limits on a related, measurable parameter.

The Test Drive

NASA Technical Reports Server (NTRS)

2004-01-01

This image taken at NASA's Jet Propulsion Laboratory shows engineers rehearsing the sol 133 (June 8, 2004) drive into 'Endurance' crater by NASA's Mars Exploration Rover Opportunity. Engineers and scientists have recreated the martian surface and slope the rover will encounter using a combination of bare and thinly sand-coated rocks, simulated martian 'blueberries' and a platform tilted at a 25-degree angle. The results of this test convinced engineers that the rover was capable of driving up and down a straight slope before it attempted the actual drive on Mars.

VLSI (Very Large Scale Integrated) Design of a 16 Bit Very Fast Pipelined Carry Look Ahead Adder.

DTIC Science & Technology

1983-09-01

the ability for systems engineers to custom design digital integrated circuits. Until recently, the design of integrated circuits has been...traditionally carried out by a select group of logic designers working in semiconductor laboratories. Systems engineers had to "make do" or "fit in" the...products of these labs to realize their designs. The systems engineers had little participation in the actual design of the chip. The MED and CONWAY design

Small engine components test facility compressor testing cell at NASA Lewis Research Center

NASA Technical Reports Server (NTRS)

Brokopp, Richard A.; Gronski, Robert S.

1992-01-01

LeRC has designed and constructed a new test facility. This facility, called the Small Engine Components Facility (SECTF) is used to test gas turbines and compressors at conditions similar to actual engine conditions. The SECTF is comprised of a compressor testing cell and a turbine testing cell. Only the compressor testing cell is described. The capability of the facility, the overall facility design, the instrumentation used in the facility, and the data acquisition system are discussed in detail.

Program Aids Design Of Fluid-Circulating Systems

NASA Technical Reports Server (NTRS)

Bacskay, Allen; Dalee, Robert

1992-01-01

Computer Aided Systems Engineering and Analysis (CASE/A) program is interactive software tool for trade study and analysis, designed to increase productivity during all phases of systems engineering. Graphics-based command-driven software package provides user-friendly computing environment in which engineer analyzes performance and interface characteristics of ECLS/ATC system. Useful during all phases of spacecraft-design program, from initial conceptual design trade studies to actual flight, including pre-flight prediction and in-flight analysis of anomalies. Written in FORTRAN 77.

Review of Air Force Compressor Blade and Vane Rework and It’s Impact on Performance and Costs

DTIC Science & Technology

1990-05-01

rework effort for reasons other than FOD. The actuarial data for March 1988, indicate that there are 977 J-79-17 engines and 2413 J-79-15 engines...maintenance shops about once every seven years (Engine Depot actuarial data). Consequently, the increased fuel cost to be used for rework cost comparisons...actual count made by personnel at Oklahoma City was only for the month of August. Additional information was based on actuarial data, assuming the data

Applying CPR to a gas utility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lowe, R.

1995-12-31

The latest management tool to hit the United States over the past five years is Core Process Re-engineering (CPR). Though not as radical a procedure as the well-known rescue method it shares an abbreviation with, it is viewed as the radical thinking of a business process. CPR has helped breathe new life into gas and electric utilities in recent years, which have been using it to find ways to increase customer satisfaction, decrease operating costs, reduce process time and/or increase quality. The first phase of a typical project identifies and reviews current processes and obtains information that can point outmore » re-engineering opportunities. The second phase involves the actual redesign of the current process. In this phase new teams may be formed, since the skill requirements are different (creative thinking becomes very important, for instance). Once alternatives are finalized and approved, the actual change process begins. Implementing all the recommendations can take several years, primarily because of labor and regulatory implications; therefore, planning the implementation is the most important part of the project. First, develop an overall implementation strategy. This overall strategy should address four major questions: What to implement? Who will implement? When to implement? How to implement? CPR is not an automatic solution to a problem. Any company wanting to expedite a CPR effort should consider the following factors: Align the CPR objectives to the overall company objectives; Ensure that senior management is actively involved and supports the CPR activities; Select the right team of people and ensure they are committed to the project; Develop a case for change and instill a sense of urgency in all the stakeholders; Focus on business results and not on specific activities; and Communicate, communicate, communicate.« less

New engineering: from knowledge to competences

NASA Astrophysics Data System (ADS)

Cartagena, M. C.; Tarquis, A. M.; Arce, A.

2009-04-01

One of the main innovations of Bologna system has been to link learning outcomes, ECTS workload based credits and competences. Competences represent a dynamic combination of knowledge, understanding, skills and abilities. Competences can be distinguished in subject specific and generic ones (instrumental, interpersonal and systemic competences). Actually in Spain Engineering degrees are changing to the new University educational system and should aim to satisfy the real needs of European society. This change has been long and complex, particularly. on the issue that have influenced curricular change Consultation with "actors" and "stakeholders", the definition of academic and professionals profiles and the translation of these into desired learning outcomes. Generic competences or transferable skills are relevant for preparing students well for their future role in society in terms of employability and citizenship. The criteria used by the companies to select their engineers are based in a good background and capacity to adapt and to acquire new knowledge, better than specific education, even postgraduate. It was interesting to note the great importance of generic competences However, Spanish government has regulated conditions of core curriculum need for to guarantee the acquisition of the competences needs to exercise the correspondent professional activities. The new degrees should comply with the core curriculum if the graduates want maintain the legal attributions guaranteed actually by the Spanish Professional Associations. After these degrees, students can access to professional master with actually horizontal attributions of regulated professions.

14 CFR 121.175 - Airplanes: Reciprocating engine-powered: Weight limitations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Airplanes: Reciprocating engine-powered... AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Airplane Performance Operating Limitations § 121.175 Airplanes: Reciprocating engine-powered: Weight limitations. (a...