Some effects of time usage patterns on the productivity of engineers

NASA Technical Reports Server (NTRS)

Jackson, Conrad N.

1992-01-01

The performance of the 1500+ engineers at MSFC is critical to the Center's mission. Worker's performance, however, is a variable affected by ability, motivation, role understanding, and other factors. Managing subordinates' performance is a great challenges to managers. Special challenges confront the managers of engineers because engineers often work with general goals, long deadlines, and considerable autonomy. The productivity of a team or branch is a function of the productivity of each of its members. While many managers have personal theories about how to run their work group, surprisingly little systematic scientific knowledge exerts about the effects of various factors on engineers' productivity. This study is intended to help lay the foundation for such a program of research.

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

Extracting Work from Quantum Measurement in Maxwell's Demon Engines

NASA Astrophysics Data System (ADS)

Elouard, Cyril; Herrera-Martí, David; Huard, Benjamin; Auffèves, Alexia

2017-06-01

The essence of both classical and quantum engines is to extract useful energy (work) from stochastic energy sources, e.g., thermal baths. In Maxwell's demon engines, work extraction is assisted by a feedback control based on measurements performed by a demon, whose memory is erased at some nonzero energy cost. Here we propose a new type of quantum Maxwell's demon engine where work is directly extracted from the measurement channel, such that no heat bath is required. We show that in the Zeno regime of frequent measurements, memory erasure costs eventually vanish. Our findings provide a new paradigm to analyze quantum heat engines and work extraction in the quantum world.

Biodiesel Performance with Modern Engines. Cooperative Research and Development Final Report, CRADA Number CRD-05-153

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

McCormick, Robert

NREL and the National Biodiesel Board (NBB) will work cooperatively to assess the effects of biodiesel blends on the performance of modern diesel engines and emissions control systems meeting increasingly strict emissions standards. This work will include research to understand the impact of biodiesel blends on the operation and durability of particle filters and NOx control sorbents/catalysts, to quantify the effect on emission control systems performance, and to understand effects on engine component durability. Work to assess the impact of biodiesel blends on real world fleet operations will be performed. Also, research to develop appropriate ASTM standards for biodiesel qualitymore » and stability will be conducted. The cooperative project will involve engine testing and fleet evaluation studies at NREL using biodiesel from a variety of sources. In addition, NREL will work with NBB to set up an Industrial Steering Committee to design the scope for the various projects and to provide technical oversight to these projects. NREL and NBB will cooperatively communicate the study results to as broad an audience as possible.« less

Savannah River Plant engineering, design, and construction history of ``S`` projects and other work, January 1961--December 1964. Volume 2

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

Not Available

1970-03-01

The work described in this volume of ``S`` Projects History is an extension of the type of work described in Volume I. E.I. du Pont de flemours & Company had entered into Contract AT (07-2)-l with the United States Atomic Energy Commission to develop, design, construct, install, and operate facilities to produce heavy water, fissionable materials, and related products. Under this contract,, Du Pont constructed and operated the Savannah River Plant. The engineering, design, and construction for most of the larger ``S`` projects was performed by the Engineering DeDartment. For some of the large and many of the smaller projectsmore » the Engineering Department was responsible only for the construction because the Atomic Energy Division (AED) of the Explosives Department handled the other phases. The Engineering Department Costruction Division also performed the physical work for many of the plant work orders. This volume includes a general description of the Du Pont Engineering Department activities pertaining to the engineering, design, and construction of the ``S`` projects at the Savannah River Plant; brief summaries of the projects and principal work requests; and supplementary informaticn on a few subjects in Volume I for which final data was not available at the closing date. Projects and other plant engineering work which were handled entirely by the Explosives Department -- AED are not included in this history.« less

Experimental study on a co-axial pulse tube cryocooler driven by a small thermoacoustic stirling engine

NASA Astrophysics Data System (ADS)

Chen, M.; Ju, L. Y.; Hao, H. X.

2014-01-01

Small scale thermoacoustic heat engines have advantages in fields like space exploration and domestic applications considering small space occupation and ease of transport. In the present paper, the influence of resonator diameter on the general performance of a small thermoacoustic Stirling engine was experimentally investigated using helium as the working gas. Reducing the diameter of the resonator appropriately is beneficial for lower onset heating temperature, lower frequency and higher pressure amplitude. Based on the pressure distribution in the small thermoacoustic engine, an outlet for the acoustic work transmission was made to combine the engine and a miniature co-axial pulse tube cooler. The cooling performance of the whole refrigeration system without any moving part was tested. Experimental results showed that further efforts are required to optimize the engine performance and its match with the co-axial pulse tube cooler in order to obtain better cooling performance, compared with its original operating condition, driven by a traditional electrical linear compressor.

Pratt and Whitney Overview and Advanced Health Management Program

NASA Technical Reports Server (NTRS)

Inabinett, Calvin

2008-01-01

Hardware Development Activity: Design and Test Custom Multi-layer Circuit Boards for use in the Fault Emulation Unit; Logic design performed using VHDL; Layout power system for lab hardware; Work lab issues with software developers and software testers; Interface with Engine Systems personnel with performance of Engine hardware components; Perform off nominal testing with new engine hardware.

48 CFR 49.305-1 - General.

Code of Federal Regulations, 2011 CFR

2011-10-01

... the work performed by the contractor (e.g., planning, scheduling, technical study, engineering work production and supervision, placing and supervising subcontracts, and work performed by the contractor in (1...

48 CFR 49.305-1 - General.

Code of Federal Regulations, 2014 CFR

2014-10-01

... the work performed by the contractor (e.g., planning, scheduling, technical study, engineering work production and supervision, placing and supervising subcontracts, and work performed by the contractor in (1...

48 CFR 49.305-1 - General.

Code of Federal Regulations, 2013 CFR

2013-10-01

... the work performed by the contractor (e.g., planning, scheduling, technical study, engineering work production and supervision, placing and supervising subcontracts, and work performed by the contractor in (1...

48 CFR 49.305-1 - General.

Code of Federal Regulations, 2012 CFR

2012-10-01

... the work performed by the contractor (e.g., planning, scheduling, technical study, engineering work production and supervision, placing and supervising subcontracts, and work performed by the contractor in (1...

The Paper Beam: Hands-On Design for Team Work Experience of Freshman in Engineering

ERIC Educational Resources Information Center

Kalkani, Efrossini C.; Boussiakou, Iris K.; Boussiakou, Leda G.

2005-01-01

The present research refers to the assigning of a hands-on group project to freshman engineering students, evaluating their performance, and deriving conclusions on student benefits and educational advances. The research procedure included action plans for the instructor and the students, instructions to the students on performing the work,…

Exhaust turbine and jet propulsion systems

NASA Technical Reports Server (NTRS)

Leist, Karl; Knornschild, Eugen

1951-01-01

DVL experimental and analytical work on the cooling of turbine blades by using ram air as the working fluid over a sector or sectors of the turbine annulus area is summarized. The subsonic performance of ram-jet, turbo-jet, and turbine-propeller engines with both constant pressure and pulsating-flow combustion is investigated. Comparison is made with the performance of a reciprocating engine and the advantages of the gas turbine and jet-propulsion engines are analyzed. Nacelle installation methods and power-level control are discussed.

Analysis of the Magneto-Hydrodynamic (MHD) Energy Bypass Engine for High-Speed Air-Breathing Propulsion

NASA Technical Reports Server (NTRS)

Riggins, David W.

2002-01-01

The performance of the MHD energy bypass air-breathing engine for high-speed propulsion is analyzed in this investigation. This engine is a specific type of the general class of inverse cycle engines. In this paper, the general relationship between engine performance (specific impulse and specific thrust) and the overall total pressure ratio through an engine (from inlet plane to exit plane) is first developed and illustrated. Engines with large total pressure decreases, regardless of cause or source, are seen to have exponentially decreasing performance. The ideal inverse cycle engine (of which the MHD engine is a sub-set) is then demonstrated to have a significant total pressure decrease across the engine; this total pressure decrease is cycle-driven, degrades rapidly with energy bypass ratio, and is independent of any irreversibility. The ideal MHD engine (inverse cycle engine with no irreversibility other than that inherent in the MHD work interaction processes) is next examined and is seen to have an additional large total pressure decrease due to MHD-generated irreversibility in the decelerator and the accelerator. This irreversibility mainly occurs in the deceleration process. Both inherent total pressure losses (inverse cycle and MHD irreversibility) result in a significant narrowing of the performance capability of the MHD bypass engine. The fundamental characteristics of MHD flow acceleration and flow deceleration from the standpoint of irreversibility and second-law constraints are next examined in order to clarify issues regarding flow losses and parameter selection in the MM modules. Severe constraints are seen to exist in the decelerator in terms of allowable deceleration Mach numbers and volumetric (length) required for meaningful energy bypass (work interaction). Considerable difficulties are also encountered and discussed due to thermal/work choking phenomena associated with the deceleration process. Lastly, full engine simulations utilizing inlet shock systems, finite-rate chemistry, wall cooling with thermally balanced engine (fuel heat sink), fuel injection and mixing, friction, etc. are shown and discussed for both the MHD engine and the conventional scramjet. The MHD bypass engine has significantly lower performance in all categories across the Mach number range (8 to 12.2). The lower performance is attributed to the combined effects of 1) additional irreversibility and cooling requirements associated with the MHD components and 2) the total pressure decrease associated with the inverse cycle itself.

Theoretical modeling of the subject: Western and Eastern types of human reflexion.

PubMed

Lefebvre, Vladimir A

2017-12-01

The author puts forth the hypothesis that mental phenomena are connected with thermodynamic properties of large neural network. A model of the subject with reflexion and capable for meditation is constructed. The processes of reflexion and meditation are presented as the sequence of heat engines. Each subsequent engine compensates for the imperfectness of the preceding engine by performing work equal to the lost available work of the preceding one. The sequence of heat engines is regarded as a chain of the subject's mental images of the self. Each engine can be interpreted as an image of the self that the engine next to it has, and the work performed by engines as the emotions that the subject and his images are experiencing. Two types of meditation are analyzed: The dissolution in nothingness and union with the Absolute. In the first type, the initial engine is the one that yields heat to the coldest reservoir, and in the second type, the initial engine is the one that takes heat from the hottest reservoir. The main concepts of thermodynamics are reviewed in relation to the process of human reflexion. Copyright © 2017 Elsevier Ltd. All rights reserved.

Optimization of a Small-Scale Engine Using Plasma Enhanced Ignition

DTIC Science & Technology

2013-03-01

PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 6. AUTHOR(S) 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT...systems were tested in the small engine and their effects on engine performance determined through comparison with a regular spark discharge (thermal...pulse plasma discharge system purchased from Plasmatronics LLC. Air fuel ratio (λ units are used in this report) sweeps were performed at several

Small Engine Technology (SET) - Task 13 ANOPP Noise Prediction for Small Engines: Jet Noise Prediction Module, Wing Shielding Module, and System Studies Results

NASA Technical Reports Server (NTRS)

Lieber, Lysbeth; Golub, Robert (Technical Monitor)

2000-01-01

This Final Report has been prepared by AlliedSignal Engines and Systems, Phoenix, Arizona, documenting work performed during the period May 1997 through June 1999, under the Small Engines Technology Program, Contract No. NAS3-27483, Task Order 13, ANOPP Noise Prediction for Small Engines. The report specifically covers the work performed under Subtasks 4, 5 and 6. Subtask 4 describes the application of a semi-empirical procedure for jet noise prediction, subtask 5 describes the development of a procedure to predict the effects of wing shielding, and subtask 6 describes the results of system studies of the benefits of the new noise technology on business and regional aircraft.

Modelling of diesel engine fuelled with biodiesel using engine simulation software

NASA Astrophysics Data System (ADS)

Said, Mohd Farid Muhamad; Said, Mazlan; Aziz, Azhar Abdul

2012-06-01

This paper is about modelling of a diesel engine that operates using biodiesel fuels. The model is used to simulate or predict the performance and combustion of the engine by simplified the geometry of engine component in the software. The model is produced using one-dimensional (1D) engine simulation software called GT-Power. The fuel properties library in the software is expanded to include palm oil based biodiesel fuels. Experimental works are performed to investigate the effect of biodiesel fuels on the heat release profiles and the engine performance curves. The model is validated with experimental data and good agreement is observed. The simulation results show that combustion characteristics and engine performances differ when biodiesel fuels are used instead of no. 2 diesel fuel.

Mechanical equivalent of quantum heat engines.

PubMed

Arnaud, Jacques; Chusseau, Laurent; Philippe, Fabrice

2008-06-01

Quantum heat engines employ as working agents multilevel systems instead of classical gases. We show that under some conditions quantum heat engines are equivalent to a series of reservoirs at different altitudes containing balls of various weights. A cycle consists of picking up at random a ball from one reservoir and carrying it to the next, thereby performing or absorbing some work. In particular, quantum heat engines, employing two-level atoms as working agents, are modeled by reservoirs containing balls of weight 0 or 1. The mechanical model helps us prove that the maximum efficiency of quantum heat engines is the Carnot efficiency. Heat pumps and negative temperatures are considered.

Tailoring Systems Engineering Processes in a Conceptual Design Environment: A Case Study at NASA Marshall Spaceflight Center's ACO

NASA Technical Reports Server (NTRS)

Mulqueen, John; Maples, C. Dauphne; Fabisinski, Leo, III

2012-01-01

This paper provides an overview of Systems Engineering as it is applied in a conceptual design space systems department at the National Aeronautics and Space Administration (NASA) Marshall Spaceflight Center (MSFC) Advanced Concepts Office (ACO). Engineering work performed in the NASA MFSC's ACO is targeted toward the Exploratory Research and Concepts Development life cycle stages, as defined in the International Council on Systems Engineering (INCOSE) System Engineering Handbook. This paper addresses three ACO Systems Engineering tools that correspond to three INCOSE Technical Processes: Stakeholder Requirements Definition, Requirements Analysis, and Integration, as well as one Project Process Risk Management. These processes are used to facilitate, streamline, and manage systems engineering processes tailored for the earliest two life cycle stages, which is the environment in which ACO engineers work. The role of systems engineers and systems engineering as performed in ACO is explored in this paper. The need for tailoring Systems Engineering processes, tools, and products in the ever-changing engineering services ACO provides to its customers is addressed.

Work Sampling Study of an Engineering Professor during a Regular Contract Period

ERIC Educational Resources Information Center

Brink, Jan; McDonald, Dale B.

2015-01-01

Work sampling is a technique that has been employed in industry and fields such as healthcare for some time. It is a powerful technique, and an alternative to conventional stop watch time studies, used by industrial engineers to focus upon random work sampling observations. This study applies work sampling to the duties performed by an individual…

Dual compile strategy for parallel heterogeneous execution

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

Smith, Tyler Barratt; Perry, James Thomas

2012-06-01

The purpose of the Dual Compile Strategy is to increase our trust in the Compute Engine during its execution of instructions. This is accomplished by introducing a heterogeneous Monitor Engine that checks the execution of the Compute Engine. This leads to the production of a second and custom set of instructions designed for monitoring the execution of the Compute Engine at runtime. This use of multiple engines differs from redundancy in that one engine is working on the application while the other engine is monitoring and checking in parallel instead of both applications (and engines) performing the same work atmore » the same time.« less

A multipurpose information engine that can go beyond the Carnot limit

NASA Astrophysics Data System (ADS)

Rana, Shubhashis; Jayannavar, A. M.

2016-10-01

Motivated by the recent work of Mandal and Jarzynski on an autonomous Maxwell demon information engine, we have extended their model by introducing two different heat baths. The system (demon) is coupled to a memory register (tape) and a work source. The performance of the system depends on the interplay between the two sources along with the heat baths. We have found that the system can act as an engine, refrigerator or an eraser. Even the combination of any two is possible in some parameter space. We have achieved an efficiency of the engine greater than the Carnot limit. The coefficient of performance of the refrigerator is also larger than the Carnot limit.

Engineering Task Plan for the Ultrasonic Inspection of Hanford Double Shell Tanks (DST) FY2000

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

JENSEN, C.E.

2000-01-10

This document facilitates the ultrasonic examination of Hanford double-shell tanks. Included are a plan for engineering activities (individual responsibilities), plan for performance demonstration testing, and a plan for field activities (tank inspection). Also included are a Statement of Work for contractor performance of the work and a protocol to be followed should tank flaws that exceed the acceptance criteria be discovered.

Initial comparison of single cylinder Stirling engine computer model predictions with test results

NASA Technical Reports Server (NTRS)

Tew, R. C., Jr.; Thieme, L. G.; Miao, D.

1979-01-01

A NASA developed digital computer code for a Stirling engine, modelling the performance of a single cylinder rhombic drive ground performance unit (GPU), is presented and its predictions are compared to test results. The GPU engine incorporates eight regenerator/cooler units and the engine working space is modelled by thirteen control volumes. The model calculates indicated power and efficiency for a given engine speed, mean pressure, heater and expansion space metal temperatures and cooler water inlet temperature and flow rate. Comparison of predicted and observed powers implies that the reference pressure drop calculations underestimate actual pressure drop, possibly due to oil contamination in the regenerator/cooler units, methane contamination in the working gas or the underestimation of mechanical loss. For a working gas of hydrogen, the predicted values of brake power are from 0 to 6% higher than experimental values, and brake efficiency is 6 to 16% higher, while for helium the predicted brake power and efficiency are 2 to 15% higher than the experimental.

32 CFR 644.462 - Performance of restoration work by district engineer-extension of time.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 4 2010-07-01 2010-07-01 true Performance of restoration work by district... Leasehold Improvements § 644.462 Performance of restoration work by district engineer—extension of time. Where the lessor will not accept a cash settlement in lieu of restoration, or desires the work to be...

Organizational Learning, Knowledge Management Practices and Firm's Performance: An Empirical Study of a Heavy Engineering Firm in India

ERIC Educational Resources Information Center

Jain, Ajay K.; Moreno, Ana

2015-01-01

Purpose: The study aims at investigating the impact of organizational learning (OL) on the firm's performance and knowledge management (KM) practices in a heavy engineering organization in India. Design/Methodology/Approach: The data were collected from 205 middle and senior executives working in the project engineering management division of a…

Influence of the cooling degree upon performances of internal combustion engine

NASA Astrophysics Data System (ADS)

Grǎdinariu, Andrei Cristian; Mihai, Ioan

2016-12-01

Up to present, air cooling systems still raise several unsolved problems due to conditions imposed by the environment in terms of temperature and pollution levels. The present paper investigates the impact of the engine cooling degree upon its performances, as important specific power is desired for as low as possible fuel consumption. A technical solution advanced by the authors[1], consists of constructing a bi-flux compressor, which can enhance the engine's performances. The bi-flux axial compressor accomplishes two major functions, that is it cools down the engine and it also turbocharges it. The present paper investigates the temperature changes corresponding to the fresh load, during the use of a bi-flux axial compressor. This compressor is economically simple, compact, and offers an optimal response at low rotational speeds of the engine, when two compression steps are used. The influence of the relative coefficient of air temperature drop upon working agent temperature at the intercooler exit is also investigated in the present work. The variation of the thermal load coefficient by report to the working agent temperature is also investigated during engine cooling. The variation of the average combustion temperature is analyzed in correlation to the thermal load coefficient and the temperatures of the working fluid at its exit from the cooling system. An exergetic analysis was conducted upon the influence of the cooling degree on the motor fluid and the gases resulted from the combustion process.

Studies on exhaust emissions of mahua oil operated compression ignition engine.

PubMed

Kapilan, N; Reddy, R P

2009-07-01

The world is confronted with fossil fuel depletion and environmental degradation. The energy demand and pollution problems lead to research for an alternative renewable energy sources. Vegetable oils and biodiesel present a very promising alternative fuel to diesel. In this work, an experimental work was carried out to study the feasibility of using raw mahua oil (MO) as a substitute for diesel in dual fuel engine. A single cylinder diesel engine was modified to work in dual fuel mode and liquefied petroleum gas (LPG) was used as primary fuel and mahua oil was used as pilot fuel. The results show that the performance of the dual fuel engine at the injector opening pressure of 220 bar and the advanced injection timing of 30 degrees bTDC results in performance close to diesel base line (DBL) operation and lower smoke and oxides of nitrogen emission.

Determination of Tasks Required by Graduates of Manufacturing Engineering Technology Programs.

ERIC Educational Resources Information Center

Zirbel, Jay H.

1993-01-01

A Delphi panel of 14 experts identified 37 tasks performed by/qualities needed by manufacturing engineering technologists. Most important were work ethic, performance quality, communication skills, teamwork, computer applications, manufacturing basics, materials knowledge, troubleshooting, supervision, and global issues. (SK)

Quantum Stirling heat engine and refrigerator with single and coupled spin systems

NASA Astrophysics Data System (ADS)

Huang, Xiao-Li; Niu, Xin-Ya; Xiu, Xiao-Ming; Yi, Xue-Xi

2014-02-01

We study the reversible quantum Stirling cycle with a single spin or two coupled spins as the working substance. With the single spin as the working substance, we find that under certain conditions the reversed cycle of a heat engine is NOT a refrigerator, this feature holds true for a Stirling heat engine with an ion trapped in a shallow potential as its working substance. The efficiency of quantum Stirling heat engine can be higher than the efficiency of the Carnot engine, but the performance coefficient of the quantum Stirling refrigerator is always lower than its classical counterpart. With two coupled spins as the working substance, we find that a heat engine can turn to a refrigerator due to the increasing of the coupling constant, this can be explained by the properties of the isothermal line in the magnetic field-entropy plane.

Responses to different types of inquiry prompts: college students' discourse, performance, and perceptions of group work in an engineering class

NASA Astrophysics Data System (ADS)

Balgopal, Meena M.; Casper, Anne Marie A.; Atadero, Rebecca A.; Rambo-Hernandez, Karen E.

2017-08-01

Working in small groups to solve problems is an instructional strategy that allows university students in science, technology, engineering, and mathematics disciplines the opportunity to practice interpersonal and professional skills while gaining and applying discipline-specific content knowledge. Previous research indicates that not all group work prompts result in the same experiences for students. In this study we posed two types of prompts (guided and open) to undergraduate engineering students in a statics course as they participated in group work projects. We measured student discourse, student performance, and perceptions of group work. We found that guided prompts were associated with higher-level discourse and higher performance (project scores) than open prompts. Students engaged in guided prompts were more likely to discuss distribution of labour and design/calculation details of their projects than when students responded to open prompts. We posit that guided prompts, which more clearly articulate expectations of students, help students determine how to divide tasks amongst themselves and, subsequently, jump to higher levels of discourse.

Development of the Junkers-diesel Aircraft Engine

NASA Technical Reports Server (NTRS)

Gasterstadt,

1930-01-01

The working process of the Junkers engine has resulted from a series of attempts to attain high performance and to control the necessarily rapid and complete combustion at extremely high speeds. The two main problems of Diesel engines in aircraft are addressed; namely, incomplete combustion and the greater weight of Diesel engine parts compared to gasoline engines.

Assessment of exposure to polycyclic aromatic hydrocarbons in engine rooms by measurement of urinary 1-hydroxypyrene.

PubMed Central

Moen, B E; Nilsson, R; Nordlinder, R; Ovrebø, S; Bleie, K; Skorve, A H; Hollund, B E

1996-01-01

OBJECTIVE: Machinists have an increased risk of lung cancer and bladder cancer, and this may be caused by exposure to carcinogenic compounds such as asbestos and polycyclic aromatic hydrocarbons (PAHs) in the engine room. The aim of this study was to investigate the exposure of engine room personnel to PAHs, with 1-hydroxypyrene in urine as a biomarker. METHODS: Urine samples from engine room personnel (n = 51) on 10 ships arriving in different harbours were collected, as well as urine samples from a similar number of unexposed controls (n = 47) on the same ships. Urinary 1-hydroxypyrene was quantitatively measured by high performance liquid chromatography. The exposure to PAHs was estimated by a questionnaire answered by the engine room personnel. On two ships, air monitoring of PAHs in the engine room was performed at sea. Both personal monitoring and area monitoring were performed. The compounds were analysed by gas chromatography of two types (with a flame ionisation detector and with a mass spectrometer). RESULTS: Significantly more 1-hydroxypyrene was found in urine of personnel who had been working in the engine room for the past 24 hours, than in that of the unexposed seamen. The highest concentrations of 1-hydroxypyrene were found among engine room personnel who had experienced oil contamination of the skin during their work in the engine room. Stepwise logistic regression analysis showed a significant relation between the concentrations of 1-hydroxypyrene, smoking, and estimated exposure to PAHs. No PAHs were detected in the air samples. CONCLUSION: Engine room personnel who experience skin exposure to oil and oil products are exposed to PAHs during their work. This indicates that dermal uptake of PAHs is the major route of exposure. PMID:8943834

Integration of safety engineering into a cost optimized development program.

NASA Technical Reports Server (NTRS)

Ball, L. W.

1972-01-01

A six-segment management model is presented, each segment of which represents a major area in a new product development program. The first segment of the model covers integration of specialist engineers into 'systems requirement definition' or the system engineering documentation process. The second covers preparation of five basic types of 'development program plans.' The third segment covers integration of system requirements, scheduling, and funding of specialist engineering activities into 'work breakdown structures,' 'cost accounts,' and 'work packages.' The fourth covers 'requirement communication' by line organizations. The fifth covers 'performance measurement' based on work package data. The sixth covers 'baseline requirements achievement tracking.'

Site systems engineering fiscal year 1999 multi-year work plan (MYWP) update for WBS 1.8.2.2

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

GRYGIEL, M.L.

1998-10-08

Manage the Site Systems Engineering process to provide a traceable integrated requirements-driven, and technically defensible baseline. Through the Site Integration Group(SIG), Systems Engineering ensures integration of technical activities across all site projects. Systems Engineering's primary interfaces are with the RL Project Managers, the Project Direction Office and with the Project Major Subcontractors, as well as with the Site Planning organization. Systems Implementation: (1) Develops, maintains, and controls the site integrated technical baseline, ensures the Systems Engineering interfaces between projects are documented, and maintain the Site Environmental Management Specification. (2) Develops and uses dynamic simulation models for verification of the baselinemore » and analysis of alternatives. (3) Performs and documents fictional and requirements analyses. (4) Works with projects, technology management, and the SIG to identify and resolve technical issues. (5) Supports technical baseline information for the planning and budgeting of the Accelerated Cleanup Plan, Multi-Year Work Plans, Project Baseline Summaries as well as performance measure reporting. (6) Works with projects to ensure the quality of data in the technical baseline. (7) Develops, maintains and implements the site configuration management system.« less

Recent Technology Advances in Distributed Engine Control

NASA Technical Reports Server (NTRS)

Culley, Dennis

2017-01-01

This presentation provides an overview of the work performed at NASA Glenn Research Center in distributed engine control technology. This is control system hardware technology that overcomes engine system constraints by modularizing control hardware and integrating the components over communication networks.

Software Engineering Improvement Activities/Plan

NASA Technical Reports Server (NTRS)

2003-01-01

bd Systems personnel accomplished the technical responsibilities for this reporting period, as planned. A close working relationship was maintained with personnel of the MSFC Avionics Department Software Group (ED14). Work accomplishments included development, evaluation, and enhancement of a software cost model, performing literature search and evaluation of software tools available for code analysis and requirements analysis, and participating in other relevant software engineering activities. Monthly reports were submitted. This support was provided to the Flight Software Group/ED 1 4 in accomplishing the software engineering improvement engineering activities of the Marshall Space Flight Center (MSFC) Software Engineering Improvement Plan.

The history and evolution of optically accessible research engines and their impact on our understanding of engine combustion

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

Miles, Paul C.

2015-03-01

The development and application of optically accessible engines to further our understanding of in-cylinder combustion processes is reviewed, spanning early efforts in simplified engines to the more recent development of high-pressure, high-speed engines that retain the geometric complexities of modern production engines. Limitations of these engines with respect to the reproduction of realistic metal test engine characteristics and performance are identified, as well as methods that have been used to overcome these limitations. Finally, the role of the work performed in these engines on clarifying the fundamental physical processes governing the combustion process and on laying the foundation for predictivemore » engine simulation is summarized.« less

The thermodynamic efficiency of heat engines with friction

NASA Astrophysics Data System (ADS)

Bizarro, João P. S.

2012-04-01

The presence of the work done against friction is incorporated into the analysis of the efficiency of heat engines based on the first and second laws of thermodynamics. We obtain the efficiencies of Stirling and Brayton engines with friction and recover results known from finite-time thermodynamics. We show that ηfric/η ≈ (1 - Wfric/W), where ηfric/η is the ratio of the efficiencies with and without friction and Wfric/W is the fraction of the work W performed by the working fluid which is spent against friction forces.

7 CFR 1724.32 - Inspection and certification of work order construction.

Code of Federal Regulations, 2013 CFR

2013-01-01

...) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC ENGINEERING, ARCHITECTURAL SERVICES AND... construction. The provisions of this section apply to all borrower electric system facilities regardless of the... performed within 6 months of the completion of construction, and are performed by a licensed engineer...

7 CFR 1724.32 - Inspection and certification of work order construction.

Code of Federal Regulations, 2012 CFR

2012-01-01

...) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC ENGINEERING, ARCHITECTURAL SERVICES AND... construction. The provisions of this section apply to all borrower electric system facilities regardless of the... performed within 6 months of the completion of construction, and are performed by a licensed engineer...

Analysis of Aurora's Performance Simulation Engine for Three Systems

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

Freeman, Janine; Simon, Joseph

2015-07-07

Aurora Solar Inc. is building a cloud-based optimization platform to automate the design, engineering, and permit generation process of solar photovoltaic (PV) installations. They requested that the National Renewable Energy Laboratory (NREL) validate the performance of the PV system performance simulation engine of Aurora Solar’s solar design platform, Aurora. In previous work, NREL performed a validation of multiple other PV modeling tools 1, so this study builds upon that work by examining all of the same fixed-tilt systems with available module datasheets that NREL selected and used in the aforementioned study. Aurora Solar set up these three operating PV systemsmore » in their modeling platform using NREL-provided system specifications and concurrent weather data. NREL then verified the setup of these systems, ran the simulations, and compared the Aurora-predicted performance data to measured performance data for those three systems, as well as to performance data predicted by other PV modeling tools.« less

NASA Research on General Aviation Power Plants

NASA Technical Reports Server (NTRS)

Stewart, W. L.; Weber, R. J.; Willis, E. A.; Sievers, G. K.

1978-01-01

Propulsion systems are key factors in the design and performance of general aviation airplanes. NASA research programs that are intended to support improvements in these engines are described. Reciprocating engines are by far the most numerous powerplants in the aviation fleet; near-term efforts are being made to lower their fuel consumption and emissions. Longer-term work includes advanced alternatives, such as rotary and lightweight diesel engines. Work is underway on improved turbofans and turboprops.

Influencing Student Beliefs about the Role of the Civil Engineer in Society

ERIC Educational Resources Information Center

Nesbit, Susan E.; Sianchuk, Robert; Aleksejuniene, Jolanta; Kindiak, Rebecca

2012-01-01

This study suggests that community service learning experiences facilitate the reconstruction of civil engineering student beliefs about both the type of work performed by civil engineers and the broad impact of civil engineering knowledge. Further, the service learning experiences highlight for students 1) the importance of relationships between…

49 CFR 237.51 - Railroad bridge engineers.

Code of Federal Regulations, 2013 CFR

2013-10-01

... engineering work to be performed: (1) Determine the forces and stresses in railroad bridges and bridge... 49 Transportation 4 2013-10-01 2013-10-01 false Railroad bridge engineers. 237.51 Section 237.51 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION...

49 CFR 237.51 - Railroad bridge engineers.

Code of Federal Regulations, 2012 CFR

2012-10-01

... engineering work to be performed: (1) Determine the forces and stresses in railroad bridges and bridge... 49 Transportation 4 2012-10-01 2012-10-01 false Railroad bridge engineers. 237.51 Section 237.51 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION...

49 CFR 237.51 - Railroad bridge engineers.

Code of Federal Regulations, 2014 CFR

2014-10-01

... engineering work to be performed: (1) Determine the forces and stresses in railroad bridges and bridge... 49 Transportation 4 2014-10-01 2014-10-01 false Railroad bridge engineers. 237.51 Section 237.51 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION...

49 CFR 237.51 - Railroad bridge engineers.

Code of Federal Regulations, 2010 CFR

2010-10-01

... engineering work to be performed: (1) Determine the forces and stresses in railroad bridges and bridge... 49 Transportation 4 2010-10-01 2010-10-01 false Railroad bridge engineers. 237.51 Section 237.51 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION...

49 CFR 237.51 - Railroad bridge engineers.

Code of Federal Regulations, 2011 CFR

2011-10-01

... engineering work to be performed: (1) Determine the forces and stresses in railroad bridges and bridge... 49 Transportation 4 2011-10-01 2011-10-01 false Railroad bridge engineers. 237.51 Section 237.51 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION...

77 FR 8284 - Western Digital Technologies, Inc., Hard Drive Development Engineering Group Irvine (Formerly at...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-14

...'s facilities in Asia for engineering positions involving production, design, and development work... that appear to relate to production and design work and one position advertised by Western Digital in... performed new product design and their duties extend to sustaining production. AR 152, 212- 218, 228-231...

Intelligent Performance Assessment of Students' Laboratory Work in a Virtual Electronic Laboratory Environment

ERIC Educational Resources Information Center

Achumba, I. E.; Azzi, D.; Dunn, V. L.; Chukwudebe, G. A.

2013-01-01

Laboratory work is critical in undergraduate engineering courses. It is used to integrate theory and practice. This demands that laboratory activities are synchronized with lectures to maximize their derivable learning outcomes, which are measurable through assessment. The typical high costs of the traditional engineering laboratory, which often…

The Role of Work Placement in Engineering Students' Academic Performance

ERIC Educational Resources Information Center

Blicblau, Aaron Simon; Nelson, Tracey Louise; Dini, Kurosh

2016-01-01

Engineering graduates without industrial experience may find that employment is difficult to obtain immediately after completing their studies. This study investigates the impact of two arrangements of work experiences; short term (over 12 weeks, STP) and long-term (over 52 weeks, IBL) on academic grades. This study involved 240 undergraduate…

Development of GUI Type On-Line Condition Monitoring Program for a Turboprop Engine Using Labview

NASA Astrophysics Data System (ADS)

Kong, Changduk; Kim, Keonwoo

2011-12-01

Recently, an aero gas turbine health monitoring system has been developed for precaution and maintenance action against faults or performance degradations of the advanced propulsion system which occurs in severe environments such as high altitude, foreign object damage particles, hot and heavy rain and snowy atmospheric conditions. However to establish this health monitoring system, the online condition monitoring program is firstly required, and the program must monitor the engine performance trend through comparison between measured engine performance data and base performance results calculated by base engine performance model. This work aims to develop a GUI type on-line condition monitoring program for the PT6A-67 turboprop engine of a high altitude and long endurance operation UAV using LabVIEW. The base engine performance of the on-line condition monitoring program is simulated using component maps inversely generated from the limited performance deck data provided by engine manufacturer. The base engine performance simulation program is evaluated because analysis results by this program agree well with the performance deck data. The proposed on-line condition program can monitor the real engine performance as well as the trend through precise comparison between clean engine performance results calculated by the base performance simulation program and measured engine performance signals. In the development phase of this monitoring system, a signal generation module is proposed to evaluate the proposed online monitoring system. For user friendly purpose, all monitoring program are coded by LabVIEW, and monitoring examples are demonstrated using the proposed GUI type on-condition monitoring program.

Fuel saver based on electromagnetic induction for automotive engine

NASA Astrophysics Data System (ADS)

Siregar, Houtman P.; Sibarani, Maradu

2007-12-01

In the considered research is designed and analyzed the performance of the fuel saver which is based on electromagnetic induction for automotive diesel engine. The fuel saver which is based on permanent magnet has sold in market and its performance has tested. In comparison to the former fuel saver, in the proposed work is produced fuel saver which is based on electromagnetic induction. The considered research is the continuation of my former work. Performance of the produced fuel saver which is installed in the fuel line of internal combustion engine rig is compared to the performance of the standard internal combustion engine rig Speed of the engine, wire diameter of coil, and number of coil which is coiled in the winding of the the fuel saver are chosen as the testing variables. The considered research has succeeded to design the fuel saver which is based on electromagnetic induction for saving the automotive fuel consumption. Results of the research show that the addition of the fuel saver which is based on electromagnetic induction to the flow of the diesel fuel can significantly save the automative fuel consumption. In addition the designed fuel saver can reduce the opacity of the emission gas.

Measurement of Work Generation and Improvement in Performance of a Pulse Tube Engine

NASA Astrophysics Data System (ADS)

Hamaguchi, Kazuhiro; Futagi, Hiroaki; Yazaki, Taichi; Hiratsuka, Yoshikatsu

Apart from double acting type engines, Stirling engines have either 2 pistons in 2 cylinders or 2 pistons in a single cylinder. Typically, the heater, regenerator and cooler are installed between the 2 pistons. The pulse tube engine, on the other hand, consists of a single piston in a single cylinder, a pulse tube, a heater, a regenerator, a cooler and a second cooler. For this paper, a simple prototype engine that uses air at normal atmospheric pressure as the working gas was fabricated. The oscillating velocity of the working gas in the pulse tube was measured using LDV, and the work flow emitting out of the pulse tube was observed. In addition, the effect of inserting heat storage material in the pulse tube on shaft power and indicated power was examined experimentally. A dramatic increase in the shaft power was achieved.

Role of quantum correlations in light-matter quantum heat engines

NASA Astrophysics Data System (ADS)

Barrios, G. Alvarado; Albarrán-Arriagada, F.; Cárdenas-López, F. A.; Romero, G.; Retamal, J. C.

2017-11-01

We study a quantum Otto engine embedding a working substance composed of a two-level system interacting with a harmonic mode. The physical properties of the substance are described by a generalized quantum Rabi model arising in superconducting circuit realizations. We show that light-matter quantum correlation reduction during the hot bath stage and adiabatic stages act as an indicator for enhanced work extraction and efficiency, respectively. Also, we demonstrate that the anharmonic spectrum of the working substance has a direct impact on the transition from heat engine into refrigerator as the light-matter coupling is increased. These results shed light on the search for optimal conditions in the performance of quantum heat engines.

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.

EFFECTS OF MUSIC ON WORK PERFORMANCE.

DTIC Science & Technology

MUSIC , *HUMAN FACTORS ENGINEERING), (*ATTENTION, PERFORMANCE(HUMAN)), REACTION(PSYCHOLOGY), REFLEXES, ATTITUDES(PSYCHOLOGY), QUESTIONNAIRES, STIMULATION(PHYSIOLOGY), EXPERIMENTAL DESIGN, CORRELATION TECHNIQUES

19 CFR 152.102 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) Engineering, development, artwork, design work, and plans and sketches that are undertaken elsewhere than in... work to which paragraph (a)(1)(iv) of this section applies will be treated as an assist if the service or work: (i) Is performed by an individual domiciled within the United States; (ii) Is performed by...

[Development of a medical equipment support information system based on PDF portable document].

PubMed

Cheng, Jiangbo; Wang, Weidong

2010-07-01

According to the organizational structure and management system of the hospital medical engineering support, integrate medical engineering support workflow to ensure the medical engineering data effectively, accurately and comprehensively collected and kept in electronic archives. Analyse workflow of the medical, equipment support work and record all work processes by the portable electronic document. Using XML middleware technology and SQL Server database, complete process management, data calculation, submission, storage and other functions. The practical application shows that the medical equipment support information system optimizes the existing work process, standardized and digital, automatic and efficient orderly and controllable. The medical equipment support information system based on portable electronic document can effectively optimize and improve hospital medical engineering support work, improve performance, reduce costs, and provide full and accurate digital data

Role of measurement in feedback-controlled quantum engines

NASA Astrophysics Data System (ADS)

Yi, Juyeon; Kim, Yong Woon

2018-01-01

In feedback controls, measurement is an essential step in designing protocols according to outcomes. For quantum mechanical systems, measurement has another effect; to supply energy to the measured system. We verify that in feedback-controlled quantum engines, measurement plays a dual role; not only as an auxiliary to perform feedback control but also as an energy supply to drive the engines. We consider a specific engine cycle exploiting feedback control followed by projective measurement and show that the maximum bound of the extractable work is set by both the efficacy of the feedback control and the energy change caused by projective measurement. We take a concrete example of an engine using an immobile spin-1/2 particle as a working substance and suggest two possible scenarios for work extraction.

A Keyboard for Underwater Performance Assessment Battery Testing

DTIC Science & Technology

1990-11-08

Applied Engineering . This four button underwater keyboard uses only a small portion of the boards capacity. The cable is connected to the I/O 32 board via a...H.O., by Applied Engineering ) require special programming to work with the IO 32 board. If the boards are accessed directly from Apple Basic with the... Applied Engineering , 1988) is presented in the Appendix. This program will work with either the enhanced or the unenhanced version of the Apple lie. 6

33 CFR 322.3 - Activities requiring permits.

Code of Federal Regulations, 2011 CFR

2011-07-01

... States that are part of the civil works activities of the Corps of Engineers, unless covered by a... separate regulations. Agreement for construction or engineering services performed for other agencies by...

33 CFR 322.3 - Activities requiring permits.

Code of Federal Regulations, 2010 CFR

2010-07-01

... States that are part of the civil works activities of the Corps of Engineers, unless covered by a... separate regulations. Agreement for construction or engineering services performed for other agencies by...

The Impact of Structured Writing and Developing Awareness of Learning Preferences on the Performance and Attitudes of Engineering Teams

ERIC Educational Resources Information Center

Dahm, Kevin; Newell, James; Newell, Heidi; Harvey, Roberta

2009-01-01

This paper discusses efforts to develop metacognition in teams of engineering students by: first, exploring personal learning patterns, and second, ongoing biweekly journaling exercises. Thirty-three junior and senior engineering students (30 chemical engineer, one each from mechanical, civil and electrical) working on semester-long projects in…

Harbors.

DTIC Science & Technology

1981-07-01

CONTRACT OR GRANT NUMBER(e) Naval Facilities Engineering Command 200 Stovall Street r Alexandria, VA 22332 (Code 0453) s. PERFORMING ORGANIZATION NAME...AND ADDRESS 10. PROGRAM ELEMENT. PROJECT. TASK • Naval Facilities Engineering Command AREA & WORK UNIT NUMBERS < 200 Stovall Street Engineering and...Design Alexandria, VA 22332 It. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE ~ Naval Facilities Engineering Command (Code10432) July 1981 200

An efficient nonlinear Feshbach engine

NASA Astrophysics Data System (ADS)

Li, Jing; Fogarty, Thomás; Campbell, Steve; Chen, Xi; Busch, Thomas

2018-01-01

We investigate a thermodynamic cycle using a Bose-Einstein condensate (BEC) with nonlinear interactions as the working medium. Exploiting Feshbach resonances to change the interaction strength of the BEC allows us to produce work by expanding and compressing the gas. To ensure a large power output from this engine these strokes must be performed on a short timescale, however such non-adiabatic strokes can create irreversible work which degrades the engine’s efficiency. To combat this, we design a shortcut to adiabaticity which can achieve an adiabatic-like evolution within a finite time, therefore significantly reducing the out-of-equilibrium excitations in the BEC. We investigate the effect of the shortcut to adiabaticity on the efficiency and power output of the engine and show that the tunable nonlinearity strength, modulated by Feshbach resonances, serves as a useful tool to enhance the system’s performance.

The Relationship between Barrier Courses and Persistence in Engineering

ERIC Educational Resources Information Center

Suresh, Radhika

2007-01-01

Attrition in engineering programs continues to be an important issue for universities across the country. This study examined the connection between student performance in barrier courses and persistence in engineering. Quantitative results showed that high school academic experience, student behaviors (including study habits, work habits, coping…

Developing Elementary Math and Science Process Skills Through Engineering Design Instruction

NASA Astrophysics Data System (ADS)

Strong, Matthew G.

This paper examines how elementary students can develop math and science process skills through an engineering design approach to instruction. The performance and development of individual process skills overall and by gender were also examined. The study, preceded by a pilot, took place in a grade four extracurricular engineering design program in a public, suburban school district. Students worked in pairs and small groups to design and construct airplane models from styrofoam, paper clips, and toothpicks. The development and performance of process skills were assessed through a student survey of learning gains, an engineering design packet rubric (student work), observation field notes, and focus group notes. The results indicate that students can significantly develop process skills, that female students may develop process skills through engineering design better than male students, and that engineering design is most helpful for developing the measuring, suggesting improvements, and observing process skills. The study suggests that a more regular engineering design program or curriculum could be beneficial for students' math and science abilities both in this school and for the elementary field as a whole.

Responses to Different Types of Inquiry Prompts: College Students' Discourse, Performance, and Perceptions of Group Work in an Engineering Class

ERIC Educational Resources Information Center

Balgopal, Meena M.; Casper, Anne Marie A.; Atadero, Rebecca A.; Rambo-Hernandez, Karen E.

2017-01-01

Working in small groups to solve problems is an instructional strategy that allows university students in science, technology, engineering, and mathematics disciplines the opportunity to practice interpersonal and professional skills while gaining and applying discipline-specific content knowledge. Previous research indicates that not all group…

10 CFR 63.113 - Performance objectives for the geologic repository after permanent closure.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 2 2014-01-01 2014-01-01 false Performance objectives for the geologic repository after permanent closure. 63.113 Section 63.113 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DISPOSAL OF HIGH... and an engineered barrier system. (b) The engineered barrier system must be designed so that, working...

10 CFR 63.113 - Performance objectives for the geologic repository after permanent closure.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 2 2013-01-01 2013-01-01 false Performance objectives for the geologic repository after permanent closure. 63.113 Section 63.113 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DISPOSAL OF HIGH... and an engineered barrier system. (b) The engineered barrier system must be designed so that, working...

10 CFR 63.113 - Performance objectives for the geologic repository after permanent closure.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 2 2011-01-01 2011-01-01 false Performance objectives for the geologic repository after permanent closure. 63.113 Section 63.113 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DISPOSAL OF HIGH... and an engineered barrier system. (b) The engineered barrier system must be designed so that, working...

10 CFR 63.113 - Performance objectives for the geologic repository after permanent closure.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 2 2012-01-01 2012-01-01 false Performance objectives for the geologic repository after permanent closure. 63.113 Section 63.113 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DISPOSAL OF HIGH... and an engineered barrier system. (b) The engineered barrier system must be designed so that, working...

On the dynamical vs. thermodynamical performance of a β-type Stirling engine

NASA Astrophysics Data System (ADS)

Reséndiz-Antonio, Margarita; Santillán, Moisés

2014-09-01

In this work we present a simple mathematical model for a β-type Stirling engine. Despite its simplicity, the model considers all the engine’s relevant thermodynamic and mechanical aspects. The dynamic behavior of the model equation of motion is analyzed in order to obtain the sufficient conditions for engine cycling and to study the stability of the stationary regime. The performance of the engine’s thermodynamic part is also investigated. As a matter of fact, we found that it corresponds to a Carnot engine.

Optimization of thermoacoustic engine driven thermoacoustic refrigerator using response surface methodology

NASA Astrophysics Data System (ADS)

Desai, A. B.; Desai, K. P.; Naik, H. B.; Atrey, M. D.

2017-02-01

Thermoacoustic engines (TAEs) are devices which convert heat energy into useful acoustic work whereas thermoacoustic refrigerators (TARs) convert acoustic work into temperature gradient. These devices work without any moving component. Study presented here comprises of a combination system i.e. thermoacoustic engine driven thermoacoustic refrigerator (TADTAR). This system has no moving component and hence it is easy to fabricate but at the same time it is very challenging to design and construct optimized system with comparable performance. The work presented here aims to apply optimization technique to TADTAR in the form of response surface methodology (RSM). Significance of stack position and stack length for engine stack, stack position and stack length for refrigerator stack are investigated in current work. Results from RSM are compared with results from simulations using Design Environment for Low-amplitude Thermoacoustic Energy conversion (DeltaEC) for compliance.

The CF6 engine performance improvement

NASA Technical Reports Server (NTRS)

Fasching, W. A.

1982-01-01

As part of the NASA-sponsored Engine Component Improvement (ECI) Program, a feasibility analysis of performance improvement and retention concepts for the CF6-6 and CF6-50 engines was conducted and seven concepts were identified for development and ground testing: new fan, new front mount, high pressure turbine aerodynamic performance improvement, high pressure turbine roundness, high pressure turbine active clearance control, low pressure turbine active clearance control, and short core exhaust nozzle. The development work and ground testing are summarized, and the major test results and an enomic analysis for each concept are presented.

Effect of intake swirl on the performance of single cylinder direct injection diesel engine

NASA Astrophysics Data System (ADS)

Sharma, Vinod Kumar; Mohan, Man; Mouli, Chandra

2017-11-01

In the present work, the effect of inlet manifold geometry and swirl intensity on the direct injection (DI) diesel engine performance was investigated experimentally. Modifications in inlet manifold geometry have been suggested to achieve optimized swirl for the better mixing of fuel with air. The intake swirl intensities of modified cylinder head were measured in swirl test rig at different valve lifts. Later, the overall performance of 435 CC DI diesel engine was measured using modified cylinder head. In addition, the performance of engine was compared for both modified and old cylinder head. For same operating conditions, the brake power and brake specific fuel consumption was improved by 6% and 7% respectively with modified cylinder head compared to old cylinder head. The maximum brake power of 9 HP was achieved for modified cylinder head. The results revealed that the intake swirl has great influence on engine performance.

Practical internal combustion engine laser spark plug development

NASA Astrophysics Data System (ADS)

Myers, Michael J.; Myers, John D.; Guo, Baoping; Yang, Chengxin; Hardy, Christopher R.

2007-09-01

Fundamental studies on laser ignition have been performed by the US Department of Energy under ARES (Advanced Reciprocating Engines Systems) and by the California Energy Commission under ARICE (Advanced Reciprocating Internal Combustion Engine). These and other works have reported considerable increases in fuel efficiencies along with substantial reductions in green-house gas emissions when employing laser spark ignition. Practical commercial applications of this technology require low cost high peak power lasers. The lasers must be small, rugged and able to provide stable laser beam output operation under adverse mechanical and environmental conditions. New DPSS (Diode Pumped Solid State) lasers appear to meet these requirements. In this work we provide an evaluation of HESP (High Efficiency Side Pumped) DPSS laser design and performance with regard to its application as a practical laser spark plug for use in internal combustion engines.

Improving of the working process of axial compressors of gas turbine engines by using an optimization method

NASA Astrophysics Data System (ADS)

Marchukov, E.; Egorov, I.; Popov, G.; Baturin, O.; Goriachkin, E.; Novikova, Y.; Kolmakova, D.

2017-08-01

The article presents one optimization method for improving of the working process of an axial compressor of gas turbine engine. Developed method allows to perform search for the best geometry of compressor blades automatically by using optimization software IOSO and CFD software NUMECA Fine/Turbo. Optimization was performed by changing the form of the middle line in the three sections of each blade and shifts of three sections of the guide vanes in the circumferential and axial directions. The calculation of the compressor parameters was performed for work and stall point of its performance map on each optimization step. Study was carried out for seven-stage high-pressure compressor and three-stage low-pressure compressors. As a result of optimization, improvement of efficiency was achieved for all investigated compressors.

Introducing a new semi-active engine mount using force controlled variable stiffness

NASA Astrophysics Data System (ADS)

Azadi, Mojtaba; Behzadipour, Saeed; Faulkner, Gary

2013-05-01

This work introduces a new concept in designing semi-active engine mounts. Engine mounts are under continuous development to provide better and more cost-effective engine vibration control. Passive engine mounts do not provide satisfactory solution. Available semi-active and active mounts provide better solutions but they are more complex and expensive. The variable stiffness engine mount (VSEM) is a semi-active engine mount with a simple ON-OFF control strategy. However, unlike available semi-active engine mounts that work based on damping change, the VSEM works based on the static stiffness change by using a new fast response force controlled variable spring. The VSEM is an improved version of the vibration mount introduced by the authors in their previous work. The results showed significant performance improvements over a passive rubber mount. The VSEM also provides better vibration control than a hydromount at idle speed. Low hysteresis and the ability to be modelled by a linear model in low-frequency are the advantages of the VSEM over the vibration isolator introduced earlier and available hydromounts. These specifications facilitate the use of VSEM in the automotive industry, however, further evaluation and developments are needed for this purpose.

Experimentation in software engineering

NASA Technical Reports Server (NTRS)

Basili, V. R.; Selby, R. W.; Hutchens, D. H.

1986-01-01

Experimentation in software engineering supports the advancement of the field through an iterative learning process. In this paper, a framework for analyzing most of the experimental work performed in software engineering over the past several years is presented. A variety of experiments in the framework is described and their contribution to the software engineering discipline is discussed. Some useful recommendations for the application of the experimental process in software engineering are included.

Unified Engineering Software System

NASA Technical Reports Server (NTRS)

Purves, L. R.; Gordon, S.; Peltzman, A.; Dube, M.

1989-01-01

Collection of computer programs performs diverse functions in prototype engineering. NEXUS, NASA Engineering Extendible Unified Software system, is research set of computer programs designed to support full sequence of activities encountered in NASA engineering projects. Sequence spans preliminary design, design analysis, detailed design, manufacturing, assembly, and testing. Primarily addresses process of prototype engineering, task of getting single or small number of copies of product to work. Written in FORTRAN 77 and PROLOG.

Mathematical modeling and characteristic analysis for over-under turbine based combined cycle engine

NASA Astrophysics Data System (ADS)

Ma, Jingxue; Chang, Juntao; Ma, Jicheng; Bao, Wen; Yu, Daren

2018-07-01

The turbine based combined cycle engine has become the most promising hypersonic airbreathing propulsion system for its superiority of ground self-starting, wide flight envelop and reusability. The simulation model of the turbine based combined cycle engine plays an important role in the research of performance analysis and control system design. In this paper, a turbine based combined cycle engine mathematical model is built on the Simulink platform, including a dual-channel air intake system, a turbojet engine and a ramjet. It should be noted that the model of the air intake system is built based on computational fluid dynamics calculation, which provides valuable raw data for modeling of the turbine based combined cycle engine. The aerodynamic characteristics of turbine based combined cycle engine in turbojet mode, ramjet mode and mode transition process are studied by the mathematical model, and the influence of dominant variables on performance and safety of the turbine based combined cycle engine is analyzed. According to the stability requirement of thrust output and the safety in the working process of turbine based combined cycle engine, a control law is proposed that could guarantee the steady output of thrust by controlling the control variables of the turbine based combined cycle engine in the whole working process.

Energy efficient engine high pressure turbine ceramic shroud support technology report

NASA Technical Reports Server (NTRS)

Nelson, W. A.; Carlson, R. G.

1982-01-01

This work represents the development and fabrication of ceramic HPT (high pressure turbine) shrouds for the Energy Efficient Engine (E3). Details are presented covering the work performed on the ceramic shroud development task of the NASA/GE Energy Efficient Engine (E3) component development program. The task consists of four phases which led to the selection of a ZrO2-BY2O3 ceramic shroud material system, the development of an automated plasma spray process to produce acceptable shroud structures, the fabrication of select shroud systems for evaluation in laboratory, component, and CF6-50 engine testing, and finally, the successful fabrication of ZrO2-8Y2O3/superpeg, engine quality shrouds for the E3 engine.

Parametric Study Conducted of Rocket- Based, Combined-Cycle Nozzles

NASA Technical Reports Server (NTRS)

Steffen, Christopher J., Jr.; Smith, Timothy D.

1998-01-01

Having reached the end of the 20th century, our society is quite familiar with the many benefits of recycling and reusing the products of civilization. The high-technology world of aerospace vehicle design is no exception. Because of the many potential economic benefits of reusable launch vehicles, NASA is aggressively pursuing this technology on several fronts. One of the most promising technologies receiving renewed attention is Rocket-Based, Combined-Cycle (RBCC) propulsion. This propulsion method combines many of the efficiencies of high-performance jet aircraft with the power and high-altitude capability of rocket engines. The goal of the present work at the NASA Lewis Research Center is to further understand the complex fluid physics within RBCC engines that govern system performance. This work is being performed in support of NASA's Advanced Reusable Technologies program. A robust RBCC engine design optimization demands further investigation of the subsystem performance of the engine's complex propulsion cycles. The RBCC propulsion system under consideration at Lewis is defined by four modes of operation in a singlestage- to-orbit configuration. In the first mode, the engine functions as a rocket-driven ejector. When the rocket engine is switched off, subsonic combustion (mode 2) is present in the ramjet mode. As the vehicle continues to accelerate, supersonic combustion (mode 3) occurs in the ramjet mode. Finally, as the edge of the atmosphere is approached and the engine inlet is closed off, the rocket is reignited and the final accent to orbit is undertaken in an all-rocket mode (mode 4). The performance of this fourth and final mode is the subject of this present study. Performance is being monitored in terms of the amount of thrust generated from a given amount of propellant.

Intelligent Life-Extending Controls for Aircraft Engines Studied

NASA Technical Reports Server (NTRS)

Guo, Ten-Huei

2005-01-01

Current aircraft engine controllers are designed and operated to provide desired performance and stability margins. Except for the hard limits for extreme conditions, engine controllers do not usually take engine component life into consideration during the controller design and operation. The end result is that aircraft pilots regularly operate engines under unnecessarily harsh conditions to strive for optimum performance. The NASA Glenn Research Center and its industrial and academic partners have been working together toward an intelligent control concept that will include engine life as part of the controller design criteria. This research includes the study of the relationship between control action and engine component life as well as the design of an intelligent control algorithm to provide proper tradeoffs between performance and engine life. This approach is expected to maintain operating safety while minimizing overall operating costs. In this study, the thermomechanical fatigue (TMF) of a critical component was selected to demonstrate how an intelligent engine control algorithm can significantly extend engine life with only a very small sacrifice in performance. An intelligent engine control scheme based on modifying the high-pressure spool speed (NH) was proposed to reduce TMF damage from ground idle to takeoff. The NH acceleration schedule was optimized to minimize the TMF damage for a given rise-time constraint, which represents the performance requirement. The intelligent engine control scheme was used to simulate a commercial short-haul aircraft engine.

Creating Simple Windchill Admin Tools Using Info*Engine

NASA Technical Reports Server (NTRS)

Jones, Corey; Kapatos, Dennis; Skradski, Cory

2012-01-01

Being a Windchill administrator often requires performing simple yet repetitive tasks on large sets of objects. These can include renaming, deleting, checking in, undoing checkout, and much more. This is especially true during a migration. Fortunately, PTC has provided a simple way to dynamically interact with Windchill using Info*Engine. This presentation will describe how to create simple Info*Engine tasks capable of saving Windchill 10.0 administrators hours of tedious work. It will also show how these tasks can be combined and displayed on a simple JSP page that acts as a "Windchill Administrator Dashboard/Toolbox". The attendee will learn some valuable tasks Info*Engine capable of performing. The attendee will gain a basic understanding of how to perform and implement Info*Engine tasks. The attendee will learn what's involved in creating a JSP page that displays Info*Engine tasks

7 CFR 1788.47 - Policy requirements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... AGRICULTURE (CONTINUED) RUS FIDELITY AND INSURANCE REQUIREMENTS FOR ELECTRIC AND TELECOMMUNICATIONS BORROWERS Insurance for Contractors, Engineers, and Architects, Telecommunications Borrowers § 1788.47 Policy requirements. (a) Contractors, engineers, and architects performing work for borrowers under construction...

7 CFR 1788.47 - Policy requirements.

Code of Federal Regulations, 2012 CFR

2012-01-01

... AGRICULTURE (CONTINUED) RUS FIDELITY AND INSURANCE REQUIREMENTS FOR ELECTRIC AND TELECOMMUNICATIONS BORROWERS Insurance for Contractors, Engineers, and Architects, Telecommunications Borrowers § 1788.47 Policy requirements. (a) Contractors, engineers, and architects performing work for borrowers under construction...

7 CFR 1788.47 - Policy requirements.

Code of Federal Regulations, 2014 CFR

2014-01-01

... AGRICULTURE (CONTINUED) RUS FIDELITY AND INSURANCE REQUIREMENTS FOR ELECTRIC AND TELECOMMUNICATIONS BORROWERS Insurance for Contractors, Engineers, and Architects, Telecommunications Borrowers § 1788.47 Policy requirements. (a) Contractors, engineers, and architects performing work for borrowers under construction...

7 CFR 1788.47 - Policy requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AGRICULTURE (CONTINUED) RUS FIDELITY AND INSURANCE REQUIREMENTS FOR ELECTRIC AND TELECOMMUNICATIONS BORROWERS Insurance for Contractors, Engineers, and Architects, Telecommunications Borrowers § 1788.47 Policy requirements. (a) Contractors, engineers, and architects performing work for borrowers under construction...

7 CFR 1788.47 - Policy requirements.

Code of Federal Regulations, 2013 CFR

2013-01-01

... AGRICULTURE (CONTINUED) RUS FIDELITY AND INSURANCE REQUIREMENTS FOR ELECTRIC AND TELECOMMUNICATIONS BORROWERS Insurance for Contractors, Engineers, and Architects, Telecommunications Borrowers § 1788.47 Policy requirements. (a) Contractors, engineers, and architects performing work for borrowers under construction...

An overview of in-flight plume diagnostics for rocket engines

NASA Technical Reports Server (NTRS)

Madzsar, G. C.; Bickford, R. L.; Duncan, D. B.

1992-01-01

An overview and progress report of the work performed or sponsored by LeRC toward the development of in-flight plume spectroscopy technology for health and performance monitoring of liquid propellant rocket engines are presented. The primary objective of this effort is to develop technology that can be utilized on any flight engine. This technology will be validated by a hardware demonstration of a system capable of being retrofitted onto the Space Shuttle Main Engines for spectroscopic measurements during flight. The philosophy on system definition and status on the development of instrumentation, optics, and signal processing with respect to implementation on a flight engine are discussed.

Autonomous Propulsion System Technology Being Developed to Optimize Engine Performance Throughout the Lifecycle

NASA Technical Reports Server (NTRS)

Litt, Jonathan S.

2004-01-01

The goal of the Autonomous Propulsion System Technology (APST) project is to reduce pilot workload under both normal and anomalous conditions. Ongoing work under APST develops and leverages technologies that provide autonomous engine monitoring, diagnosing, and controller adaptation functions, resulting in an integrated suite of algorithms that maintain the propulsion system's performance and safety throughout its life. Engine-to-engine performance variation occurs among new engines because of manufacturing tolerances and assembly practices. As an engine wears, the performance changes as operability limits are reached. In addition to these normal phenomena, other unanticipated events such as sensor failures, bird ingestion, or component faults may occur, affecting pilot workload as well as compromising safety. APST will adapt the controller as necessary to achieve optimal performance for a normal aging engine, and the safety net of APST algorithms will examine and interpret data from a variety of onboard sources to detect, isolate, and if possible, accommodate faults. Situations that cannot be accommodated within the faulted engine itself will be referred to a higher level vehicle management system. This system will have the authority to redistribute the faulted engine's functionality among other engines, or to replan the mission based on this new engine health information. Work is currently underway in the areas of adaptive control to compensate for engine degradation due to aging, data fusion for diagnostics and prognostics of specific sensor and component faults, and foreign object ingestion detection. In addition, a framework is being defined for integrating all the components of APST into a unified system. A multivariable, adaptive, multimode control algorithm has been developed that accommodates degradation-induced thrust disturbances during throttle transients. The baseline controller of the engine model currently being investigated has multiple control modes that are selected according to some performance or operational criteria. As the engine degrades, parameters shift from their nominal values. Thus, when a new control mode is swapped in, a variable that is being brought under control might have an excessive initial error. The new adaptive algorithm adjusts the controller gains on the basis of the level of degradation to minimize the disruptive influence of the large error on other variables and to recover the desired thrust response.

LLMapReduce: Multi-Level Map-Reduce for High Performance Data Analysis

DTIC Science & Technology

2016-05-23

LLMapReduce works with several schedulers such as SLURM, Grid Engine and LSF. Keywords—LLMapReduce; map-reduce; performance; scheduler; Grid Engine ...SLURM; LSF I. INTRODUCTION Large scale computing is currently dominated by four ecosystems: supercomputing, database, enterprise , and big data [1...interconnects [6]), High performance math libraries (e.g., BLAS [7, 8], LAPACK [9], ScaLAPACK [10]) designed to exploit special processing hardware, High

D-21B RBCC Modification Feasibility Study

NASA Technical Reports Server (NTRS)

1999-01-01

This report presents a feasibility study on the modifications required to re-engine the Lockheed D-21 Drone for use as a NASA RBCC engine. An introduction, background information, engine configuration and performance, propulsion system integration, loads/thermal analysis, avionics/systems, flight test results, costs and work schedule, and some conclusions are presented.

Performance Parameters Analysis of an XD3P Peugeot Engine Using Artificial Neural Networks (ANN) Concept in MATLAB

NASA Astrophysics Data System (ADS)

Rangaswamy, T.; Vidhyashankar, S.; Madhusudan, M.; Bharath Shekar, H. R.

2015-04-01

The current trends of engineering follow the basic rule of innovation in mechanical engineering aspects. For the engineers to be efficient, problem solving aspects need to be viewed in a multidimensional perspective. One such methodology implemented is the fusion of technologies from other disciplines in order to solve the problems. This paper mainly deals with the application of Neural Networks in order to analyze the performance parameters of an XD3P Peugeot engine (used in Ministry of Defence). The basic propaganda of the work is divided into two main working stages. In the former stage, experimentation of an IC engine is carried out in order to obtain the primary data. In the latter stage the primary database formed is used to design and implement a predictive neural network in order to analyze the output parameters variation with respect to each other. A mathematical governing equation for the neural network is obtained. The obtained polynomial equation describes the characteristic behavior of the built neural network system. Finally, a comparative study of the results is carried out.

Assessment of potential asbestos exposures from jet engine overhaul work.

PubMed

Mlynarek, S P; Van Orden, D R

2012-06-01

Asbestos fibers have been used in a wide variety of products and numerous studies have shown that exposures from the use or manipulation of these products can vary widely. Jet engines contained various components (gaskets, clamps, o-rings and insulation) that contained asbestos that potentially could release airborne fibers during routine maintenance or during an engine overhaul. To evaluate the potential exposures to aircraft mechanics, a Pratt & Whitney JT3D jet engine was obtained and overhauled by experienced mechanics using tools and work practices similar to those used since the time this engine was manufactured. This study has demonstrated that the disturbance of asbestos-containing gaskets, o-rings, and other types of asbestos-containing components, while performing overhaul work to a jet engine produces very few airborne fibers, and that virtually none of these aerosolized fibers is asbestos. The overhaul work was observed to be dirty and oily. The exposures to the mechanics and bystanders were several orders of magnitude below OSHA exposure regulations, both current and historic. The data presented underscore the lack of risk to the health of persons conducting this work and to other persons in proximity to it from airborne asbestos. Copyright © 2012 Elsevier Inc. All rights reserved.

Performance Evaluation and Modeling of Erosion Resistant Turbine Engine Thermal Barrier Coatings

NASA Technical Reports Server (NTRS)

Miller, Robert A.; Zhu, Dongming; Kuczmarski, Maria

2008-01-01

The erosion resistant turbine thermal barrier coating system is critical to the rotorcraft engine performance and durability. The objective of this work was to determine erosion resistance of advanced thermal barrier coating systems under simulated engine erosion and thermal gradient environments, thus validating a new thermal barrier coating turbine blade technology for future rotorcraft applications. A high velocity burner rig based erosion test approach was established and a new series of rare earth oxide- and TiO2/Ta2O5- alloyed, ZrO2-based low conductivity thermal barrier coatings were designed and processed. The low conductivity thermal barrier coating systems demonstrated significant improvements in the erosion resistance. A comprehensive model based on accumulated strain damage low cycle fatigue is formulated for blade erosion life prediction. The work is currently aiming at the simulated engine erosion testing of advanced thermal barrier coated turbine blades to establish and validate the coating life prediction models.

Testing and performance characteristics of a 1-kW free piston Stirling engine

NASA Technical Reports Server (NTRS)

Schreiber, J.

1983-01-01

A 1 kW single cylinder free piston Stirling engine, configured as a research engine, was tested with helium working gas. The engine features a posted displacer and dashpot load. The test results show the engine power output and efficiency to be lower than those observed during acceptance tests by the manufacturer. Engine tests results are presented for operation at the two heater head temperatures and with two regenerator porosities, along with flow test results for the heat exchangers.

Study on Practical Application of Turboprop Engine Condition Monitoring and Fault Diagnostic System Using Fuzzy-Neuro Algorithms

NASA Astrophysics Data System (ADS)

Kong, Changduk; Lim, Semyeong; Kim, Keunwoo

2013-03-01

The Neural Networks is mostly used to engine fault diagnostic system due to its good learning performance, but it has a drawback due to low accuracy and long learning time to build learning data base. This work builds inversely a base performance model of a turboprop engine to be used for a high altitude operation UAV using measuring performance data, and proposes a fault diagnostic system using the base performance model and artificial intelligent methods such as Fuzzy and Neural Networks. Each real engine performance model, which is named as the base performance model that can simulate a new engine performance, is inversely made using its performance test data. Therefore the condition monitoring of each engine can be more precisely carried out through comparison with measuring performance data. The proposed diagnostic system identifies firstly the faulted components using Fuzzy Logic, and then quantifies faults of the identified components using Neural Networks leaned by fault learning data base obtained from the developed base performance model. In leaning the measuring performance data of the faulted components, the FFBP (Feed Forward Back Propagation) is used. In order to user's friendly purpose, the proposed diagnostic program is coded by the GUI type using MATLAB.

Performance testing of 3D point cloud software

NASA Astrophysics Data System (ADS)

Varela-González, M.; González-Jorge, H.; Riveiro, B.; Arias, P.

2013-10-01

LiDAR systems are being used widely in recent years for many applications in the engineering field: civil engineering, cultural heritage, mining, industry and environmental engineering. One of the most important limitations of this technology is the large computational requirements involved in data processing, especially for large mobile LiDAR datasets. Several software solutions for data managing are available in the market, including open source suites, however, users often unknown methodologies to verify their performance properly. In this work a methodology for LiDAR software performance testing is presented and four different suites are studied: QT Modeler, VR Mesh, AutoCAD 3D Civil and the Point Cloud Library running in software developed at the University of Vigo (SITEGI). The software based on the Point Cloud Library shows better results in the loading time of the point clouds and CPU usage. However, it is not as strong as commercial suites in working set and commit size tests.

Self-Oscillating Josephson Quantum Heat Engine

NASA Astrophysics Data System (ADS)

Marchegiani, G.; Virtanen, P.; Giazotto, F.; Campisi, M.

2016-11-01

The design of a mesoscopic self-oscillating heat engine that works thanks to purely quantum effects is presented. The proposed scheme is amenable to experimental implementation with current state-of-the-art nanotechnology and materials. One of the main features of the structure is its versatility: The engine can deliver work to a generic load without galvanic contact. This versatility makes it a promising building block for low-temperature on-chip energy-management applications. The heat engine consists of a circuit featuring a thermoelectric element based on a ferromagnetic insulator-superconductor tunnel junction and a Josephson weak link that realizes a purely quantum dc-ac converter. This makeup enables the contactless transfer of work to the load (a generic RL circuit). The performance of the heat engine is investigated as a function of the thermal gradient applied to the thermoelectric junction. Power up to 1 pW can be delivered to a load RL=10 Ω .

Advanced Gas Turbine (AGT) Technology Project

NASA Technical Reports Server (NTRS)

1986-01-01

Engine testing, ceramic component fabrication and evaluation, component performance rig testing, and analytical studies comprised AGT 100 activities during the 1985 year. Ten experimental assemblies (builds) were evaluated using two engines. Accrued operating time was 120 hr of burning and 170 hr total, bringing cumulative total operating time to 395 hr, all devoid of major failures. Tests identified the generator seals as the primary working fluid leakage sources. Power transfer clutch operation was demonstrated. An alpha SiC gasifier rotor engine test resulted in blade tip failures. Recurring case vibration and shaft whip have limited gasifier shaft speeds to 84%. Ceramic components successfully engine tested now include the SiC scroll assembly, Si3N3 turbine rotor, combustor assembly, regenerator disk bulkhead, turbine vanes, piston rings, and couplings. A compressor shroud design change to reduce heat recirculation back to the inlet was executed. Ceramic components activity continues to focus on the development of state-of-the-art material strength characteristics in full-scale engine hardware. Fiber reinforced glass-ceramic composite turbine (inner) backplates were fabricated by Corning Glass Works. The BMAS/III material performed well in engine testing. Backplates of MAS material have not been engine tested.

Systems Engineering Processes at NASA/SR-71 Pratt and Whitney J58 Engine

NASA Technical Reports Server (NTRS)

Donastorg, Cristina

2010-01-01

This summer I was given several opportunities at NASA's Dryden Flight Research Center (DFRC). The first opportunity was given to me by a Senior Propulsion Engineer, Kurtt Kloesel, to work in a specialized engineering discipline. My task was to research the Pratt & Whitney J58 engine that was used on the SR-71 Blackbird. I entered the data I collected into engine modeling software programs in order to receive certain outputs, such as net thrust. I also had to take a "crash course" in propulsion in order to better understand the research I was performing. To facilitate my understanding of propulsion principals and formulas, I worked many problems out of thermodynamics and propulsion textbooks and entered the given values of various situations into the modeling software.

System analysis of a piston steam engine employing the uniflow principle, a study in optimized performance

NASA Technical Reports Server (NTRS)

Peoples, J. A.

1975-01-01

Results are reported which were obtained from a mathematical model of a generalized piston steam engine configuration employing the uniflow principal. The model accounted for the effects of clearance volume, compression work, and release volume. A simple solution is presented which characterizes optimum performance of the steam engine, based on miles per gallon. Development of the mathematical model is presented. The relationship between efficiency and miles per gallon is developed. An approach to steam car analysis and design is presented which has purpose rather than lucky hopefulness. A practical engine design is proposed which correlates to the definition of the type engine used. This engine integrates several system components into the engine structure. All conclusions relate to the classical Rankine Cycle.

Perm State University HPC-hardware and software services: capabilities for aircraft engine aeroacoustics problems solving

NASA Astrophysics Data System (ADS)

Demenev, A. G.

2018-02-01

The present work is devoted to analyze high-performance computing (HPC) infrastructure capabilities for aircraft engine aeroacoustics problems solving at Perm State University. We explore here the ability to develop new computational aeroacoustics methods/solvers for computer-aided engineering (CAE) systems to handle complicated industrial problems of engine noise prediction. Leading aircraft engine engineering company, including “UEC-Aviadvigatel” JSC (our industrial partners in Perm, Russia), require that methods/solvers to optimize geometry of aircraft engine for fan noise reduction. We analysed Perm State University HPC-hardware resources and software services to use efficiently. The performed results demonstrate that Perm State University HPC-infrastructure are mature enough to face out industrial-like problems of development CAE-system with HPC-method and CFD-solvers.

Developing Avionics Hardware and Software for Rocket Engine Testing

NASA Technical Reports Server (NTRS)

Aberg, Bryce Robert

2014-01-01

My summer was spent working as an intern at Kennedy Space Center in the Propulsion Avionics Branch of the NASA Engineering Directorate Avionics Division. The work that I was involved with was part of Rocket University's Project Neo, a small scale liquid rocket engine test bed. I began by learning about the layout of Neo in order to more fully understand what was required of me. I then developed software in LabView to gather and scale data from two flowmeters and integrated that code into the main control software. Next, I developed more LabView code to control an igniter circuit and integrated that into the main software, as well. Throughout the internship, I performed work that mechanics and technicians would do in order to maintain and assemble the engine.

Continued Development of Expert System Tools for NPSS Engine Diagnostics

NASA Technical Reports Server (NTRS)

Lewandowski, Henry

1996-01-01

The objectives of this grant were to work with previously developed NPSS (Numerical Propulsion System Simulation) tools and enhance their functionality; explore similar AI systems; and work with the High Performance Computing Communication (HPCC) K-12 program. Activities for this reporting period are briefly summarized and a paper addressing the implementation, monitoring and zooming in a distributed jet engine simulation is included as an attachment.

23 CFR 230.407 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-04-01

... HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION CIVIL RIGHTS EXTERNAL PROGRAMS Construction Contract... means a Federal or State employee regularly employed and experienced in civil rights policies, practices... include preliminary engineering work in project development or engineering services performed by or for a...

23 CFR 230.407 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-04-01

... HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION CIVIL RIGHTS EXTERNAL PROGRAMS Construction Contract... means a Federal or State employee regularly employed and experienced in civil rights policies, practices... include preliminary engineering work in project development or engineering services performed by or for a...

23 CFR 230.407 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-04-01

... HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION CIVIL RIGHTS EXTERNAL PROGRAMS Construction Contract... means a Federal or State employee regularly employed and experienced in civil rights policies, practices... include preliminary engineering work in project development or engineering services performed by or for a...

23 CFR 230.407 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-04-01

... HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION CIVIL RIGHTS EXTERNAL PROGRAMS Construction Contract... means a Federal or State employee regularly employed and experienced in civil rights policies, practices... include preliminary engineering work in project development or engineering services performed by or for a...

23 CFR 230.407 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-04-01

... HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION CIVIL RIGHTS EXTERNAL PROGRAMS Construction Contract... means a Federal or State employee regularly employed and experienced in civil rights policies, practices... include preliminary engineering work in project development or engineering services performed by or for a...

Metamaterial-Based Cylinders Used for Invisible Cloak Realization

DTIC Science & Technology

2011-08-01

Branimir Ivsic Tin Komljenovic University of Zagreb Faculty of Electrical Engineering and Computing Unska 3 Zagreb , Croatia HR-10000...NUMBER 5e. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) University of Zagreb Faculty of Electrical Engineering and Computing...Unska 3 Zagreb , Croatia HR-10000 8. PERFORMING ORGANIZATION REPORT NUMBER N/A 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS

Performance assessment and optimization of an irreversible nano-scale Stirling engine cycle operating with Maxwell-Boltzmann gas

NASA Astrophysics Data System (ADS)

Ahmadi, Mohammad H.; Ahmadi, Mohammad-Ali; Pourfayaz, Fathollah

2015-09-01

Developing new technologies like nano-technology improves the performance of the energy industries. Consequently, emerging new groups of thermal cycles in nano-scale can revolutionize the energy systems' future. This paper presents a thermo-dynamical study of a nano-scale irreversible Stirling engine cycle with the aim of optimizing the performance of the Stirling engine cycle. In the Stirling engine cycle the working fluid is an Ideal Maxwell-Boltzmann gas. Moreover, two different strategies are proposed for a multi-objective optimization issue, and the outcomes of each strategy are evaluated separately. The first strategy is proposed to maximize the ecological coefficient of performance (ECOP), the dimensionless ecological function (ecf) and the dimensionless thermo-economic objective function ( F . Furthermore, the second strategy is suggested to maximize the thermal efficiency ( η), the dimensionless ecological function (ecf) and the dimensionless thermo-economic objective function ( F). All the strategies in the present work are executed via a multi-objective evolutionary algorithms based on NSGA∥ method. Finally, to achieve the final answer in each strategy, three well-known decision makers are executed. Lastly, deviations of the outcomes gained in each strategy and each decision maker are evaluated separately.

Optimization design and performance analysis of a miniature stirling engine

NASA Astrophysics Data System (ADS)

You, Zhanping; Yang, Bo; Pan, Lisheng; Hao, Changsheng

2017-10-01

Under given operation conditions, a stirling engine of 2 kW is designed which takes hydrogen as working medium. Through establishment of adiabatic model, the ways are achieved about performance improving. The ways are raising the temperature of hot terminal, lowering the temperature of cold end, increasing the average cycle pressure, speeding up the speed, phase angle being 90°, stroke volume ratio approximating to 1 and increasing the performance of regenerator.

How Bell Labs creates star performers.

PubMed

Kelley, R; Caplan, J

1993-01-01

How can managers increase the productivity of professionals when most of their work goes on inside their heads? Robert Kelley and Janet Caplan believe that defining the difference between star performers and average workers is the answer. Many managers assume that top performers are just smarter. But the authors' research at the Bell Laboratories Switching Systems Business Unit (SSBU) has revealed that the real difference between stars and average workers is not IQ but the ways top performers do their jobs. Their study has led to a training program based on the strategies of star performers. The SSBU training program, known as the Productivity Enhancement Group (PEG), uses an expert model to demystify productivity. The star engineers selected to develop the expert model identified and ranked nine work strategies, such as taking initiative, networking, and self-management. Middle performers were also asked what makes for top-quality work, but their definitions and ranking of the strategies differed significantly from those of the top performers. Taking initiative, for example, meant something very different to an average worker than it did to a star. And for the middle performers, the ability to give good presentations was a core strategy, while it was peripheral for the top engineers. Once PEG got underway, respected engineers ran the training sessions, which included case studies, work-related exercises, and frank discussion. The benefits of the program were striking: participants and managers reported substantial productivity increases in both star and average performers. The PEG program may not be a blueprint for other companies, but its message is clear: managers must focus on people, not on technology, to increase productivity in the knowledge economy.

Competences of Engineers in the Iron and Steel Industry

NASA Astrophysics Data System (ADS)

Kozhevnikov, A. V.

2017-12-01

The article presents the results of assessment of the professional performance of engineers working in the iron and steel industry. A competence-based profile of highly-qualified professionals has been built. The study of the competences of the iron and steel industry engineers has shown that their knowledge and skills may be mobilized to solve professional tasks.

Multifuel rotary aircraft engine

NASA Technical Reports Server (NTRS)

Jones, C.; Berkowitz, M.

1980-01-01

The broad objectives of this paper are the following: (1) to summarize the Curtiss-Wright design, development and field testing background in the area of rotary aircraft engines; (2) to briefly summarize past activity and update development work in the area of stratified charge rotary combustion engines; and (3) to discuss the development of a high-performance direct injected unthrottled stratified charge rotary combustion aircraft engine. Efficiency improvements through turbocharging are also discussed.

Advanced rotary engines

NASA Technical Reports Server (NTRS)

Jones, C.

1983-01-01

The broad objectives of this paper are the following: (1) to summarize the Curtiss-Wright design, development and field testing background in the area of rotary aircraft engines; (2) to briefly summarize past activity and update development work in the area of stratified charge rotary combustion engines; and (3) to discuss the development of a high-performance direct injected unthrottled stratified charge rotary combustion aircraft engine. Efficiency improvements through turbocharging are also discussed.

Small Engine Technology (SET) Task 23 ANOPP Noise Prediction for Small Engines, Wing Reflection Code

NASA Technical Reports Server (NTRS)

Lieber, Lysbeth; Brown, Daniel; Golub, Robert A. (Technical Monitor)

2000-01-01

The work performed under Task 23 consisted of the development and demonstration of improvements for the NASA Aircraft Noise Prediction Program (ANOPP), specifically targeted to the modeling of engine noise enhancement due to wing reflection. This report focuses on development of the model and procedure to predict the effects of wing reflection, and the demonstration of the procedure, using a representative wing/engine configuration.

TOPSIS-based parametric optimization of compression ignition engine performance and emission behavior with bael oil blends for different EGR and charge inlet temperature.

PubMed

Muniappan, Krishnamoorthi; Rajalingam, Malayalamurthi

2018-05-02

The demand for higher fuel energy and lesser exhaust emissions of diesel engines can be achieved by fuel being used and engine operating parameters. In the present work, effects of engine speed (RPM), injection timing (IT), injection pressure (IP), and compression ratio (CR) on performance and emission characteristics of a compression ignition (CI) engine were investigated. The ternary test fuel of 65% diesel + 25% bael oil + 10% diethyl ether (DEE) was used in this work and test was conducted at different charge inlet temperature (CIT) and exhaust gas recirculation (EGR). All the experiments are conducted at the tradeoff engine load that is 75% engine load. When operating the diesel engine with 320 K CIT, brake thermal efficiency (BTE) is improved to 28.6%, and carbon monoxide (CO) and hydrocarbon (HC) emissions have been reduced to 0.025% and 12.5 ppm at 18 CR. The oxide of nitrogen (NOx) has been reduced to 240 ppm at 1500 rpm for 30% EGR mode. Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method is frequently used in multi-factor selection and gray correlation analysis method is used to study uncertain of the systems.

Development and application of theoretical models for Rotating Detonation Engine flowfields

NASA Astrophysics Data System (ADS)

Fievisohn, Robert

As turbine and rocket engine technology matures, performance increases between successive generations of engine development are becoming smaller. One means of accomplishing significant gains in thermodynamic performance and power density is to use detonation-based heat release instead of deflagration. This work is focused on developing and applying theoretical models to aid in the design and understanding of Rotating Detonation Engines (RDEs). In an RDE, a detonation wave travels circumferentially along the bottom of an annular chamber where continuous injection of fresh reactants sustains the detonation wave. RDEs are currently being designed, tested, and studied as a viable option for developing a new generation of turbine and rocket engines that make use of detonation heat release. One of the main challenges in the development of RDEs is to understand the complex flowfield inside the annular chamber. While simplified models are desirable for obtaining timely performance estimates for design analysis, one-dimensional models may not be adequate as they do not provide flow structure information. In this work, a two-dimensional physics-based model is developed, which is capable of modeling the curved oblique shock wave, exit swirl, counter-flow, detonation inclination, and varying pressure along the inflow boundary. This is accomplished by using a combination of shock-expansion theory, Chapman-Jouguet detonation theory, the Method of Characteristics (MOC), and other compressible flow equations to create a shock-fitted numerical algorithm and generate an RDE flowfield. This novel approach provides a numerically efficient model that can provide performance estimates as well as details of the large-scale flow structures in seconds on a personal computer. Results from this model are validated against high-fidelity numerical simulations that may require a high-performance computing framework to provide similar performance estimates. This work provides a designer a new tool to conduct large-scale parametric studies to optimize a design space before conducting computationally-intensive, high-fidelity simulations that may be used to examine additional effects. The work presented in this thesis not only bridges the gap between simple one-dimensional models and high-fidelity full numerical simulations, but it also provides an effective tool for understanding and exploring RDE flow processes.

Computerized engineering logic for procurement and dedication processes

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

Tulay, M.P.

1996-12-31

This paper summarizes the work performed for designing the system and especially for calculating on-line expected performance and gives some significant results. In an attempt to better meet the needs of operations and maintenance organizations, many nuclear utility procurement engineering groups have simplified their procedures, developed on-line tools for performing the specification of replacement items, and developed relational databases containing part-level information necessary to automate the procurement process. Although these improvements have helped to reduce the engineering necessary to properly specify and accept/dedicate items for nuclear safety-related applications, a number of utilities have recognized that additional long-term savings can bemore » realized by integrating a computerized logic to assist technical procurement engineering personnel.« less

Engineered Barrier System: Physical and Chemical Environment

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

P. Dixon

2004-04-26

The conceptual and predictive models documented in this Engineered Barrier System: Physical and Chemical Environment Model report describe the evolution of the physical and chemical conditions within the waste emplacement drifts of the repository. The modeling approaches and model output data will be used in the total system performance assessment (TSPA-LA) to assess the performance of the engineered barrier system and the waste form. These models evaluate the range of potential water compositions within the emplacement drifts, resulting from the interaction of introduced materials and minerals in dust with water seeping into the drifts and with aqueous solutions forming bymore » deliquescence of dust (as influenced by atmospheric conditions), and from thermal-hydrological-chemical (THC) processes in the drift. These models also consider the uncertainty and variability in water chemistry inside the drift and the compositions of introduced materials within the drift. This report develops and documents a set of process- and abstraction-level models that constitute the engineered barrier system: physical and chemical environment model. Where possible, these models use information directly from other process model reports as input, which promotes integration among process models used for total system performance assessment. Specific tasks and activities of modeling the physical and chemical environment are included in the technical work plan ''Technical Work Plan for: In-Drift Geochemistry Modeling'' (BSC 2004 [DIRS 166519]). As described in the technical work plan, the development of this report is coordinated with the development of other engineered barrier system analysis model reports.« less

32 CFR 555.6 - Authority.

Code of Federal Regulations, 2010 CFR

2010-07-01

... OF ENGINEERS, RESEARCH AND DEVELOPMENT, LABORATORY RESEARCH AND DEVELOPMENT AND TESTS, WORK FOR OTHERS § 555.6 Authority. The following delegations of authority to perform research and development and tests apply. (a) Major Corps of Engineers Research and Development Laboratories. The major Corps of...

Performance analysis of exhaust heat recovery using organic Rankine cycle in a passenger car with a compression ignition engine

NASA Astrophysics Data System (ADS)

Ghilvacs, M.; Prisecaru, T.; Pop, H.; Apostol, V.; Prisecaru, M.; Pop, E.; Popescu, Gh; Ciobanu, C.; Mohanad, A.; Alexandru, A.

2016-08-01

Compression ignition engines transform approximately 40% of the fuel energy into power available at the crankshaft, while the rest part of the fuel energy is lost as coolant, exhaust gases and other waste heat. An organic Rankine cycle (ORC) can be used to recover this waste heat. In this paper, the characteristics of a system combining a compression ignition engine with an ORC which recover the waste heat from the exhaust gases are analyzed. The performance map of the diesel engine is measured on an engine test bench and the heat quantities wasted by the exhaust gases are calculated over the engine's entire operating region. Based on this data, the working parameters of ORC are defined, and the performance of a combined engine-ORC system is evaluated across this entire region. The results show that the net power of ORC is 6.304kW at rated power point and a maximum of 10% reduction in brake specific fuel consumption can be achieved.

Energy efficient engine component development and integration program

NASA Technical Reports Server (NTRS)

1982-01-01

The objective of the Energy Efficient Engine Component Development and Integration program is to develop, evaluate, and demonstrate the technology for achieving lower installed fuel consumption and lower operating costs in future commercial turbofan engines. Minimum goals have been set for a 12 percent reduction in thrust specific fuel consumption (TSFC), 5 percent reduction in direct operating cost (DOC), and 50 percent reduction in performance degradation for the Energy Efficient Engine (flight propulsion system) relative to the JT9D-7A reference engine. The Energy Efficienct Engine features a twin spool, direct drive, mixed flow exhaust configuration, utilizing an integrated engine nacelle structure. A short, stiff, high rotor and a single stage high pressure turbine are among the major enhancements in providing for both performance retention and major reductions in maintenance and direct operating costs. Improved clearance control in the high pressure compressor and turbines, and advanced single crystal materials in turbine blades and vanes are among the major features providing performance improvement. Highlights of work accomplished and programs modifications and deletions are presented.

X-33/RLV Program Aerospike Engines

NASA Technical Reports Server (NTRS)

1999-01-01

Substantial progress was made during the past year in support of the X-33/RLV program. X-33 activity was directed towards completing the remaining design work and building hardware to support test activities. RLV work focused on the nozzle ramp and powerpack technology tasks and on supporting vehicle configuration studies. On X-33, the design activity was completed to the detail level and the remainder of the drawings were released. Component fabrication and engine assembly activity was initiated, and the first two powerpacks and the GSE and STE needed to support powerpack testing were completed. Components fabrication is on track to support the first engine assembly schedule. Testing activity included powerpack testing and component development tests consisting of thrust cell single cell testing, CWI system spider testing, and EMA valve flow and vibration testing. Work performed for RLV was divided between engine system and technology development tasks. Engine system activity focused on developing the engine system configuration and supporting vehicle configuration studies. Also, engine requirements were developed, and engine performance analyses were conducted. In addition, processes were developed for implementing reliability, mass properties, and cost controls during design. Technology development efforts were divided between powerpack and nozzle ramp technology tasks. Powerpack technology activities were directed towards the development of a prototype powerpack and a ceramic turbine technology demonstrator (CTTD) test article which will allow testing of ceramic turbines and a close-coupled gas generator design. Nozzle technology efforts were focused on the selection of a composite nozzle supplier and on the fabrication and test of composite nozzle coupons.

Integrated Main Propulsion System Performance Reconstruction Process/Models

NASA Technical Reports Server (NTRS)

Lopez, Eduardo; Elliott, Katie; Snell, Steven; Evans, Michael

2013-01-01

The Integrated Main Propulsion System (MPS) Performance Reconstruction process provides the MPS post-flight data files needed for postflight reporting to the project integration management and key customers to verify flight performance. This process/model was used as the baseline for the currently ongoing Space Launch System (SLS) work. The process utilizes several methodologies, including multiple software programs, to model integrated propulsion system performance through space shuttle ascent. It is used to evaluate integrated propulsion systems, including propellant tanks, feed systems, rocket engine, and pressurization systems performance throughout ascent based on flight pressure and temperature data. The latest revision incorporates new methods based on main engine power balance model updates to model higher mixture ratio operation at lower engine power levels.

Electrochemical heat engine

DOEpatents

Elliott, Guy R. B.; Holley, Charles E.; Houseman, Barton L.; Sibbitt, Jr., Wilmer L.

1978-01-01

Electrochemical heat engines produce electrochemical work, and mechanical motion is limited to valve and switching actions as the heat-to-work cycles are performed. The electrochemical cells of said heat engines use molten or solid electrolytes at high temperatures. One or more reactions in the cycle will generate a gas at high temperature which can be condensed at a lower temperature with later return of the condensate to electrochemical cells. Sodium, potassium, and cesium are used as the working gases for high temperature cells (above 600 K) with halogen gases or volatile halides being used at lower temperature. Carbonates and halides are used as molten electrolytes and the solid electrolyte in these melts can also be used as a cell separator.

Colloidal heat engines: a review.

PubMed

Martínez, Ignacio A; Roldán, Édgar; Dinis, Luis; Rica, Raúl A

2016-12-21

Stochastic heat engines can be built using colloidal particles trapped using optical tweezers. Here we review recent experimental realizations of microscopic heat engines. We first revisit the theoretical framework of stochastic thermodynamics that allows to describe the fluctuating behavior of the energy fluxes that occur at mesoscopic scales, and then discuss recent implementations of the colloidal equivalents to the macroscopic Stirling, Carnot and steam engines. These small-scale motors exhibit unique features in terms of power and efficiency fluctuations that have no equivalent in the macroscopic world. We also consider a second pathway for work extraction from colloidal engines operating between active bacterial reservoirs at different temperatures, which could significantly boost the performance of passive heat engines at the mesoscale. Finally, we provide some guidance on how the work extracted from colloidal heat engines can be used to generate net particle or energy currents, proposing a new generation of experiments with colloidal systems.

48 CFR 36.501 - Performance of work by the contractor.

Code of Federal Regulations, 2011 CFR

2011-10-01

... SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 36.501.... Specialties such as plumbing, heating, and electrical work are usually subcontracted, and should not normally...

48 CFR 36.501 - Performance of work by the contractor.

Code of Federal Regulations, 2013 CFR

2013-10-01

... SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 36.501.... Specialties such as plumbing, heating, and electrical work are usually subcontracted, and should not normally...

48 CFR 36.501 - Performance of work by the contractor.

Code of Federal Regulations, 2012 CFR

2012-10-01

... SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 36.501.... Specialties such as plumbing, heating, and electrical work are usually subcontracted, and should not normally...

48 CFR 36.501 - Performance of work by the contractor.

Code of Federal Regulations, 2010 CFR

2010-10-01

... SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 36.501.... Specialties such as plumbing, heating, and electrical work are usually subcontracted, and should not normally...

48 CFR 36.501 - Performance of work by the contractor.

Code of Federal Regulations, 2014 CFR

2014-10-01

... SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Contract Clauses 36.501.... Specialties such as plumbing, heating, and electrical work are usually subcontracted, and should not normally...

KSC-2011-2599

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. - Technicians carefully remove main engine No. 3 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. NASA/Jim Grossmann

KSC-2011-2600

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. - Technicians carefully remove main engine No. 3 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. NASA/Jim Grossmann

KSC-2011-2598

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. - Technicians carefully remove main engine No. 3 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. NASA/Jim Grossmann

KSC-2011-2597

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. - Technicians carefully remove main engine No. 3 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. NASA/Jim Grossmann

Application of Adjusted Canonical Correlation Analysis (ACCA) to study the association between mathematics in Level 1 and Level 2 and performance of engineering disciplines in Level 2

NASA Astrophysics Data System (ADS)

Peiris, T. S. G.; Nanayakkara, K. A. D. S. A.

2017-09-01

Mathematics plays a key role in engineering sciences as it assists to develop the intellectual maturity and analytical thinking of engineering students and exploring the student academic performance has received great attention recently. The lack of control over covariates motivates the need for their adjustment when measuring the degree of association between two sets of variables in Canonical Correlation Analysis (CCA). Thus to examine the individual effects of mathematics in Level 1 and Level 2 on engineering performance in Level 2, two adjusted analyses in CCA: Part CCA and Partial CCA were applied for the raw marks of engineering undergraduates for three different disciplines, at the Faculty of Engineering, University of Moratuwa, Sri Lanka. The joint influence of mathematics in Level 1 and Level 2 is significant on engineering performance in Level 2 irrespective of the engineering disciplines. The individual effect of mathematics in Level 2 is significantly higher compared to the individual effect of mathematics in Level 1 on engineering performance in Level 2. Furthermore, the individual effect of mathematics in Level 1 can be negligible. But, there would be a notable indirect effect of mathematics in Level 1 on engineering performance in Level 2. It can be concluded that the joint effect of mathematics in both Level 1 and Level 2 is immensely beneficial to improve the overall academic performance at the end of Level 2 of the engineering students. Furthermore, it was found that the impact mathematics varies among engineering disciplines. As partial CCA and partial CCA are not widely explored in applied work, it is recommended to use these techniques for various applications.

NACA Photographer Films a Ramjet Test

NASA Image and Video Library

1946-10-21

A National Advisory Committee for Aeronautics (NACA) photographer films the test of a ramjet engine at the Lewis Flight Propulsion Laboratory. The laboratory had an arsenal of facilities to test the engines and their components, and immersed itself in the study of turbojet and ramjet engines during the mid-1940s. Combustion, fuel injection, flameouts, and performance at high altitudes were of particular interest to researchers. They devised elaborate schemes to instrument the engines in order to record temperature, pressure, and other data. Many of the tests were also filmed so Lewis researchers could visually review the combustion performance along with the data. The photographer in this image was using high-speed film to document a thrust augmentation study at Lewis’ Jet Static Propulsion Laboratory. The ramjet in this photograph was equipped with a special afterburner as part of a general effort to improve engine performance. Lewis’ Photo Lab was established in 1942. The staff was expanded over the next few years as more test facilities became operational. The Photo Lab’s staff and specialized equipment have been key research tools for decades. They accompany pilots on test flights, use high-speed cameras to capture fleeting processes like combustion, and work with technology, such as the Schlieren camera, to capture supersonic aerodynamics. In addition, the group has documented construction projects, performed publicity work, created images for reports, and photographed data recording equipment.

Experimental investigation on Performance and Emission Characteristics of J20, P20, N20 Biodiesel blends and Sound Characteristics of P20 Biodiesel blend Used in Single Cylinder Diesel Engine

NASA Astrophysics Data System (ADS)

rajasekar, R.; karthik, N.; Xavier, Goldwin

2017-05-01

Present work provides the effect of biodiesel blends and Sound Characteristics of P20 Biodiesel blend compared with Performance and emission Characteristics of diesel. Methods and analysis biodiesel blends was prepared by the Transesterification Process. Experiments were conducted in single cylinder constant speed direct injection diesel engine for various test fuels. Research is mainly focused on pongamia oil. It was observed that a 20% Pongamia oil blends and its properties were similar to diesel. The results showed that 20% Pongamia oil blends gave better performance, less in noise and emission compared with ester of Jatropha and neem oil blends. Hence Pongamia blends can be used in existing diesel engine without compromising the engine performance.

Improvement of thermal performance of gamma-type stirling engine

NASA Astrophysics Data System (ADS)

Saenyot, Khanuengchat; Chamdee, Peerapong; Raksrithong, Pawin; Locharoenrat, Kitsakorn; Lekchaum, Sarai

2018-06-01

The gamma-type stirling engine was designed and fabricated using three main types of the materials for the engine assembly in order to get better the heat transfer between the cold and hot sides of the engine cylinders. Stainless steel and brass were applied for the hot cylinder, whereas aluminum was used for the cold cylinder. We have achieved the indicated work, engine speed and indicated power of 71.64 mJ, 599 rpm and 0.71 J/s, respectively. Furthermore, we were able to accomplish the constant temperature difference of 300 K with the thermal efficiency of 40 %. The improvement of the engine performance was confirmed by the heat flow simulation via the Solidwork program. Our inexpensive home-made engine is expected to be very useful for the people in the rural areas where the electricity is unable to reach them.

Rocketdyne RBCC Engine Concept Development

NASA Technical Reports Server (NTRS)

Ratckin, G.; Goldman, A.; Ortwerth, P.; Weisberg, S.

1999-01-01

Boeing Rocketdyne is pursuing the development of Rocket Based Combined Cycle (RBCC), propulsion systems as demonstrated by significant contract work in the hypersonic arena (ART, NASP, SCT, system studies) and over 12 years of steady company discretionary investment. The Rocketdyne concept is a fixed geometry integrated rocket, ramjet, scramjet which is hydrogen fueled and uses hydrogen regenerative cooling. The baseline engine structural configuration uses an integral structure that eliminates panel seals. seal purge gas, and closeout side attachments. Rocketdyne's experimental RBCC engine (Engine A5) was constructed under contract with the NASA Marshall Space Flight Center. Engine A5 models the complete flight engine flowpath consisting of an inlet, isolator, airbreathing combustor and nozzle. High performance rocket thrusters are integrated into the engine to enable both air-augmented rocket (AAR) and pure rocket operation. Engine A5 was tested in CASL's new FAST facility as an air-augmented rocket, a ramjet and a pure rocket. Measured performance demonstrated vision vehicle performance levels for Mach 3 AAR operation and ramjet operation from Mach 3 to 4. Rocket mode performance was above predictions. For the first time. testing also demonstrated transition from AAR operation to ramjet operation. This baseline configuration has also been shown, in previous testing, to perform well in the scramjet mode.

Improved Stirling engine performance using jet impingement

NASA Technical Reports Server (NTRS)

Johnson, D. C.; Britt, E. J.; Thieme, L. G.

1982-01-01

Of the many factors influencing the performance of a Stirling engine, that of transferring the combustion gas heat into the working fluid is crucial. By utilizing the high heat transfer rates obtainable with a jet impingement heat transfer system, it is possible to reduce the flame temperature required for engine operation. Also, the required amount of heater tube surface area may be reduced, resulting in a decrease in the engine nonswept volume and a related increase in engine efficiency. A jet impingement heat transfer system was designed by Rasor Associates, Inc., and tested in the GPU-3 Stirling engine at the NASA Lewis Research Center. For a small penalty in pumping power (less than 0.5% of engine output) the jet impingement heat transfer system provided a higher combustion-gas-side heat transfer coefficient and a smoothing of heater temperature profiles resulting in lower combustion system temperatures and a 5 to 8% increase in engine power output and efficiency.

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

Adaptive Gas Turbine Engine Control for Deterioration Compensation Due to Aging

NASA Technical Reports Server (NTRS)

Litt, Jonathan S.; Parker, Khary I.; Chatterjee, Santanu

2003-01-01

This paper presents an ad hoc adaptive, multivariable controller tuning rule that compensates for a thrust response variation in an engine whose performance has been degraded though use and wear. The upset appears when a large throttle transient is performed such that the engine controller switches from low-speed to high-speed mode. A relationship was observed between the level of engine degradation and the overshoot in engine temperature ratio, which was determined to cause the thrust response variation. This relationship was used to adapt the controller. The method is shown to work very well up to the operability limits of the engine. Additionally, since the level of degradation can be estimated from sensor data, it would be feasible to implement the adaptive control algorithm on-line.

High Thrust-to-Power Annular Engine Technology

NASA Technical Reports Server (NTRS)

Patterson, Michael J.; Thomas, Robert E.; Crofton, Mark W.; Young, Jason A.; Foster, John E.

2015-01-01

Gridded ion engines have the highest efficiency and total impulse of any mature electric propulsion technology, and have been successfully implemented for primary propulsion in both geocentric and heliocentric environments with excellent ground/in-space correlation of performance. However, they have not been optimized to maximize thrust-to-power, an important parameter for Earth orbit transfer applications. This publication discusses technology development work intended to maximize this parameter. These activities include investigating the capabilities of a non-conventional design approach, the annular engine, which has the potential of exceeding the thrust-to-power of other EP technologies. This publication discusses the status of this work, including the fabrication and initial tests of a large-area annular engine. This work is being conducted in collaboration among NASA Glenn Research Center, The Aerospace Corporation, and the University of Michigan.

High Thrust-to-Power Annular Engine Technology

NASA Technical Reports Server (NTRS)

Patterson, Michael; Thomas, Robert; Crofton, Mark; Young, Jason A.; Foster, John E.

2015-01-01

Gridded ion engines have the highest efficiency and total impulse of any mature electric propulsion technology, and have been successfully implemented for primary propulsion in both geocentric and heliocentric environments with excellent ground-in-space correlation of performance. However, they have not been optimized to maximize thrust-to-power, an important parameter for Earth orbit transfer applications. This publication discusses technology development work intended to maximize this parameter. These activities include investigating the capabilities of a non-conventional design approach, the annular engine, which has the potential of exceeding the thrust-to-power of other EP technologies. This publication discusses the status of this work, including the fabrication and initial tests of a large-area annular engine. This work is being conducted in collaboration among NASA Glenn Research Center, The Aerospace Corporation, and the University of Michigan.

Space Transportation Booster Engine Configuration Study. Volume 3: Program Cost estimates and work breakdown structure and WBS dictionary

NASA Technical Reports Server (NTRS)

1989-01-01

The objective of the Space Transportation Booster Engine Configuration Study is to contribute to the ALS development effort by providing highly reliable, low cost booster engine concepts for both expendable and reusable rocket engines. The objectives of the Space Transportation Booster Engine (STBE) Configuration Study were: (1) to identify engine development configurations which enhance vehicle performance and provide operational flexibility at low cost; and (2) to explore innovative approaches to the follow-on Full-Scale Development (FSD) phase for the STBE.

24 CFR 968.140 - On-site inspections.

Code of Federal Regulations, 2011 CFR

2011-04-01

... inspection personnel during modernization, whether work is performed by contract or force account labor and with or without the services of an architect/engineer, to ensure work quality and progress. [58 FR...

NETL - Supercomputing: NETL Simulation Based Engineering User Center (SBEUC)

ScienceCinema

None

2018-02-07

NETL's Simulation-Based Engineering User Center, or SBEUC, integrates one of the world's largest high-performance computers with an advanced visualization center. The SBEUC offers a collaborative environment among researchers at NETL sites and those working through the NETL-Regional University Alliance.

NETL - Supercomputing: NETL Simulation Based Engineering User Center (SBEUC)

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

None

2013-09-30

NETL's Simulation-Based Engineering User Center, or SBEUC, integrates one of the world's largest high-performance computers with an advanced visualization center. The SBEUC offers a collaborative environment among researchers at NETL sites and those working through the NETL-Regional University Alliance.

Laser engines operating by resonance absorption.

PubMed

Garbuny, M; Pechersky, M J

1976-05-01

The coherence properties and power levels of lasers available at present lend themselves to the remote operation of mechanical engines by resonance absorption in a working gas. Laser radiation is capable of producing extremely high temperatures in a gas. Limits to the achievable temperatures in the working gas of an engine are imposed by the solid walls and by loss of resonance absorption due to thermal saturation, bleaching, and dissociation. However, it is shown that by proper control of the laser beam in space, time, and frequency, as well as by choice of the absorbing gas, these limits are to a great extent removed so that very high temperatures are indeed attainable. The working gas is largely monatomic, preferably helium with the addition of a few volume percent of an absorber. Such a gas mixture, internally heated, permits an optimization of the expansion ratio, with resulting thermal efficiencies and work ratios, not achievable in conventional engines. A relationship between thermal efficiency and work ratio is derived that is quite general for the optimization condition. The performance of laser piston engines, turbines, and the Stirling cycle based on these principles is discussed and compared with conventional engine operation. Finally, a brief discussion is devoted to the possibility and concepts for the direct conversion of selective vibrational or electronic excitation into mechanical work, bypassing the translational degrees of freedom.

Evaluation of the flame propagation within an SI engine using flame imaging and LES

NASA Astrophysics Data System (ADS)

He, Chao; Kuenne, Guido; Yildar, Esra; van Oijen, Jeroen; di Mare, Francesca; Sadiki, Amsini; Ding, Carl-Philipp; Baum, Elias; Peterson, Brian; Böhm, Benjamin; Janicka, Johannes

2017-11-01

This work shows experiments and simulations of the fired operation of a spark ignition engine with port-fuelled injection. The test rig considered is an optically accessible single cylinder engine specifically designed at TU Darmstadt for the detailed investigation of in-cylinder processes and model validation. The engine was operated under lean conditions using iso-octane as a substitute for gasoline. Experiments have been conducted to provide a sound database of the combustion process. A planar flame imaging technique has been applied within the swirl- and tumble-planes to provide statistical information on the combustion process to complement a pressure-based comparison between simulation and experiments. This data is then analysed and used to assess the large eddy simulation performed within this work. For the simulation, the engine code KIVA has been extended by the dynamically thickened flame model combined with chemistry reduction by means of pressure dependent tabulation. Sixty cycles have been simulated to perform a statistical evaluation. Based on a detailed comparison with the experimental data, a systematic study has been conducted to obtain insight into the most crucial modelling uncertainties.

Analysis of heat recovery of diesel engine using intermediate working fluid

NASA Astrophysics Data System (ADS)

Jin, Lei; Zhang, Jiang; Tan, Gangfeng; Liu, Huaming

2017-07-01

The organic Rankine cycle (ORC) is an effective way to recovery the engine exhaust heat. The thermal stability of the evaporation system is significant for the stable operation of the ORC system. In this paper, the performance of the designed evaporation system which combines with the intermediate fluid for recovering the exhaust waste heat from a diesel engine is evaluated. The thermal characteristics of the target diesel engine exhaust gas are evaluated based on the experimental data firstly. Then, the mathematical model of the evaporation system is built based on the geometrical parameters and the specific working conditions of ORC. Finally, the heat transfer characteristics of the evaporation system are estimated corresponding to three typical operating conditions of the diesel engine. The result shows that the exhaust temperature at the evaporator outlet increases slightly with the engine speed and load. In the evaporator, the heat transfer coefficient of the Rankine working fluid is slightly larger than the intermediate fluid. However, the heat transfer coefficient of the intermediate fluid in the heat exchanger is larger than the exhaust side. The heat transfer areas of the evaporator in both the two-phase zone and the preheated zone change slightly along with the engine working condition while the heat transfer areas of the overheated zone has changed obviously. The maximum heat transfer rate occurs in the preheating zone while the minimum value occurs in the overheating zone. In addition, the Rankine working fluid temperature at the evaporator outlet is not sensitively affected by the torque and speed of the engine and the organic fluid flow is relatively stable. It is concluded that the intermediate fluid could effectively reduce the physical changes of Rankine working fluid in the evaporator outlet due to changes in engine operating conditions.

A Creep Model for High-Density Snow

DTIC Science & Technology

2017-04-01

Robert B. Haehnel April 2017 Approved for public release; distribution is unlimited. The U.S. Army Engineer Research and Development... Research and Development Center (ERDC) Cold Regions Research and Engineering Laboratory (CRREL) 72 Lyme Road Hanover, NH 03755-1290 Final Report...The work was performed by the Terrestrial and Cryospheric Sciences Branch (CEERD-RRG), U.S. Army Engineer Research and Development Center, Cold

Using Collaborative Engineering to Inform Collaboration Engineering

NASA Technical Reports Server (NTRS)

Cooper, Lynne P.

2012-01-01

Collaboration is a critical competency for modern organizations as they struggle to compete in an increasingly complex, global environment. A large body of research on collaboration in the workplace focuses both on teams, investigating how groups use teamwork to perform their task work, and on the use of information systems to support team processes ("collaboration engineering"). This research essay presents collaboration from an engineering perspective ("collaborative engineering"). It uses examples from professional and student engineering teams to illustrate key differences in collaborative versus collaboration engineering and investigates how challenges in the former can inform opportunities for the latter.

23 CFR 646.216 - General procedures.

Code of Federal Regulations, 2010 CFR

2010-04-01

... subject to the provisions of § 646.216(b) (2), preliminary engineering work on railroad-highway projects... contracts where such work is regularly performed for the railroad in its own work under such contracts at... wholly or partly affected by a highway project, the costs of work necessary to functionally restore such...

Advanced Turbine Technology Applications Project (ATTAP) 1993 annual report

NASA Technical Reports Server (NTRS)

1994-01-01

This report summarizes work performed by AlliedSignal Engines, a unit of AlliedSignal Aerospace Company, during calendar year 1993, toward development and demonstration of structural ceramic technology for automotive gas turbine engines. This work was performed for the U.S. Department of Energy (DOE) under National Aeronautics and Space Administration (NASA) Contract DEN3-335, Advanced Turbine Technology Applications Project (ATFAP). During 1993, the test bed used to demonstrate ceramic technology was changed from the AlliedSignal Engines/Garrett Model AGT101 regenerated gas turbine engine to the Model 331-200(CT) engine. The 331-200(CT) ceramic demonstrator is a fully-developed test platform based on the existing production AlliedSignal 331-200(ER) gas turbine auxiliary power unit (APU), and is well suited to evaluating ceramic turbine blades and nozzles. In addition, commonality of the 331-200(CT) engine with existing gas turbine APU's in commercial service provides the potential for field testing of ceramic components. The 1993 ATTAP activities emphasized design modifications of the 331-200 engine test bed to accommodate ceramic first-stage turbine nozzles and blades, fabrication of the ceramic components, ceramic component proof and rig tests, operational tests of the test bed equipped with the ceramic components, and refinement of critical ceramic design technologies.

Development and Engineering Design in Support of "Rover Ranch": A K-12 Outreach Software Project

NASA Technical Reports Server (NTRS)

Pascali, Raresh

2003-01-01

A continuation of the initial development started in the summer of 1999, the body of work performed in support of 'ROVer Ranch' Project during the present fellowship dealt with the concrete concept implementation and resolution of the related issues. The original work performed last summer focused on the initial examination and articulation of the concept treatment strategy, audience and market analysis for the learning technologies software. The presented work focused on finalizing the set of parts to be made available for building an AERCam Sprint type robot and on defining, testing and implementing process necessary to convert the design engineering files to VRML files. Through reverse engineering, an initial set of mission critical systems was designed for beta testing in schools. The files were created in ProEngineer, exported to VRML 1.0 and converted to VRML 97 (VRML 2.0) for final integration in the software. Attributes for each part were assigned using an in-house developed JAVA based program. The final set of attributes for each system, their mutual interaction and the identification of the relevant ones to be tracked, still remain to be decided.

Internal combustion engine with thermochemical recuperation fed by ethanol steam reforming products - feasibility study

NASA Astrophysics Data System (ADS)

Cesana, O.; Gutman, M.; Shapiro, M.; Tartakovsky, L.

2016-08-01

This research analyses the performance of a spark ignition engine fueled by ethanol steam reforming products. The basic concept involves the use of the internal combustion engine's (ICE) waste heat to promote onboard reforming of ethanol. The reformer and the engine performance were simulated and analyzed using GT-Suite, Chem CAD and Matlab software. The engine performance with different compositions of ethanol reforming products was analyzed, in order to find the optimal working conditions of the ICE - reformer system. The analysis performed demonstrated the capability to sustain the endothermic reactions in the reformer and to reform the liquid ethanol to hydrogen-rich gaseous fuel using the heat of the exhaust gases. However, the required reformer's size is quite large: 39 x 89 x 73 cm, which makes a feasibility of its mounting on board a vehicle questionable. A comparison with ICE fed by gasoline or liquid ethanol doesn't show a potential of efficiency improvement, but can be considered as a tool of additional emissions reduction.

Training to Enhance Design Team Performance: A Cure for Tunnel Vision

NASA Technical Reports Server (NTRS)

Parker, James W.; Parker, Nelson C. (Technical Monitor)

2001-01-01

Design Team performance is a function of the quality and degree of academic training and the cumulative, learned experience of the individual members of the team. Teamwork, leadership, and communications certainly are factors that affect the measure of the performance of the team, but they are not addressed here. This paper focuses on accelerating the learned experience of team members and describes an organizational approach that can significantly increase the effective experience level for any engineering design team. The performance measure of the whole team can be increased by increasing the engineering disciplines' cross awareness of each other and by familiarizing them with their affect at the system level. Discipline engineers know their own discipline well, but typically are not intimately familiar with their technical interaction with and dependencies on all the other disciplines of engineering. These dependencies are design integration functions and are worked out well by the discipline engineers as long as they are involved in the design of types of systems that they have experience with.

Performance Enhancement of One and Two-Shaft Industrial Turboshaft Engines Topped With Wave Rotors

NASA Astrophysics Data System (ADS)

Fatsis, Antonios

2018-05-01

Wave rotors are rotating equipment designed to exchange energy between high and low enthalpy fluids by means of unsteady pressure waves. In turbomachinery, they can be used as topping devices to gas turbines aiming to improve performance. The integration of a wave rotor into a ground power unit is far more attractive than into an aeronautical application, since it is not accompanied by any inconvenience concerning the over-weight and extra dimensioning. Two are the most common types of ground industrial gas turbines: The one-shaft and the two-shaft engines. Cycle analysis for both types of gas turbine engines topped with a four-port wave rotor is calculated and their performance is compared to the performance of the baseline engine accordingly. It is concluded that important benefits are obtained in terms of specific work and specific fuel consumption, especially compared to baseline engines with low compressor pressure ratio and low turbine inlet temperature.

Interdisciplinary Interactions During R&D and Early Design of Large Engineered Systems

NASA Technical Reports Server (NTRS)

McGowan, Anna-Maria Rivas

2014-01-01

Designing Large-Scale Complex Engineered Systems (LaCES) such as aircraft and submarines requires the input of thousands of engineers and scientists whose work is proximate in neither time nor space. Comprehensive knowledge of the system is dispersed among specialists whose expertise is in typically one system component or discipline. This study examined the interactive work practices among such specialists seeking to improve engineering practice through a rigorous and theoretical understanding of current practice. This research explored current interdisciplinary practices and perspectives during R&D and early LaCES design and identified why these practices and perspectives prevail and persist. The research design consisted of a three-fold, integrative approach that combined an open-ended survey, semi-structured interviews, and ethnography. Significant empirical data from experienced engineers and scientists in a large engineering organization were obtained and integrated with theories from organization science and engineering. Qualitative analysis was used to obtain a holistic, contextualized understanding. The over-arching finding is that issues related to cognition, organization, and social interrelations mostly dominate interactions across disciplines. Engineering issues, such as the integration of hardware or physics-based models, are not as significant. For example, organization culture is an important underlying factor that guided researchers more toward individual sovereignty over cross-disciplinarity. The organization structure and the engineered system architecture also serve as constraints to the engineering work. Many differences in work practices were observed, including frequency and depth of interactions, definition or co-construction of requirements, clarity or creation of the system architecture, work group proximity, and cognitive challenges. Practitioners are often unaware of these differences resulting in confusion and incorrect assumptions regarding work expectations. Cognitively, the enactment and coconstruction of knowledge are the fundamental tasks of the interdisciplinary interactions. Distributed and collective cognition represent most of the efforts. Argument, ignorance, learning, and creativity are interrelated aspects of the interactions that cause discomfort but yield benefits such as problem mitigation, broader understanding, and improved system design and performance. The quality and quantity of social interrelations are central to all work across disciplines with reciprocity, respectful engagement, and heedful interrelations being significant to the effectiveness of the engineering and scientific work.

Treatment of highway runoff : engineered filter media for pollutant removal through enhanced sorption : final report.

DOT National Transportation Integrated Search

2015-07-27

The work performed in this study focused on the investigation of the use of engineered biofiltration layers to enhance the removal of roadway stormwater runoff contaminants (specifically nutrients, solids, heavy metals, and pH). Six Georgia native gr...

ICTNET at Web Track 2009 Diversity task

DTIC Science & Technology

2009-11-01

performance. On the World Wide Web, there exist many documents which represents several implicit subtopics. We used commerce search engines to gather those...documents. In this task, our work can be divided into five steps. First, we collect documents returned by commerce search engines , and considered

Integrated Design Engineering Analysis (IDEA) Environment - Aerodynamics, Aerothermodynamics, and Thermal Protection System Integration Module

NASA Technical Reports Server (NTRS)

Kamhawi, Hilmi N.

2011-01-01

This report documents the work performed during from March 2010 October 2011. The Integrated Design and Engineering Analysis (IDEA) environment is a collaborative environment based on an object-oriented, multidisciplinary, distributed environment using the Adaptive Modeling Language (AML) as the underlying framework. This report will focus on describing the work done in the area of extending the aerodynamics, and aerothermodynamics module using S/HABP, CBAERO, PREMIN and LANMIN. It will also detail the work done integrating EXITS as the TPS sizing tool.

KSC-2011-2676

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Technicians complete the removal of main engine No. 1 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

KSC-2011-2675

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Technicians complete the removal of main engine No. 1 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

KSC-2011-2667

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Technicians carefully remove main engine No. 1 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

KSC-2011-2671

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Technicians complete the removal of main engine No. 1 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

KSC-2011-2669

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Technicians carefully remove main engine No. 1 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

KSC-2011-2674

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Technicians complete the removal of main engine No. 1 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

KSC-2011-2672

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Technicians complete the removal of main engine No. 1 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

KSC-2011-2666

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Technicians carefully remove main engine No. 1 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

KSC-2011-2670

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Technicians carefully remove main engine No. 1 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

KSC-2011-2601

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. - Technicians complete the removal of main engine No. 3 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. NASA/Jim Grossmann

KSC-2011-2673

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Technicians complete the removal of main engine No. 1 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

KSC-2011-2668

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Technicians carefully remove main engine No. 1 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

KSC-2011-2602

NASA Image and Video Library

2011-03-31

CAPE CANAVERAL, Fla. - Technicians complete the removal of main engine No. 3 from space shuttle Discovery using a specially designed engine installer, called a Hyster forklift. The work is taking place in Orbiter Processing Facility-2 at NASA's Kennedy Space Center in Florida. The removal is part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. NASA/Jim Grossmann

Dissipated energy and entropy production for an unconventional heat engine: the stepwise `circular cycle'

NASA Astrophysics Data System (ADS)

di Liberto, Francesco; Pastore, Raffaele; Peruggi, Fulvio

2011-05-01

When some entropy is transferred, by means of a reversible engine, from a hot heat source to a colder one, the maximum efficiency occurs, i.e. the maximum available work is obtained. Similarly, a reversible heat pumps transfer entropy from a cold heat source to a hotter one with the minimum expense of energy. In contrast, if we are faced with non-reversible devices, there is some lost work for heat engines, and some extra work for heat pumps. These quantities are both related to entropy production. The lost work, i.e. ? , is also called 'degraded energy' or 'energy unavailable to do work'. The extra work, i.e. ? , is the excess of work performed on the system in the irreversible process with respect to the reversible one (or the excess of heat given to the hotter source in the irreversible process). Both quantities are analysed in detail and are evaluated for a complex process, i.e. the stepwise circular cycle, which is similar to the stepwise Carnot cycle. The stepwise circular cycle is a cycle performed by means of N small weights, dw, which are first added and then removed from the piston of the vessel containing the gas or vice versa. The work performed by the gas can be found as the increase of the potential energy of the dw's. Each single dw is identified and its increase, i.e. its increase in potential energy, evaluated. In such a way it is found how the energy output of the cycle is distributed among the dw's. The size of the dw's affects entropy production and therefore the lost and extra work. The distribution of increases depends on the chosen removal process.

A static organization in a dynamic context--A qualitative study of changes in working conditions for Swedish engine officers.

PubMed

Lundh, Monica; Rydstedt, Leif W

2016-07-01

During the last decades the shipping industry has undergone rapid technical developments and experienced hard economic conditions and increased striving for profitability. This has led to reduced staffing and changes in task performance, which has been reported to increase workload for the remaining seafarers. The working conditions on board have a number of distinct and in many ways unique characteristics, which makes the job demands and resources for seafarers unique in several ways. The purpose of this study was to assess how engine room staff perceives how these major technical and organizational changes in the shipping industry have affected job demands as well as resources. The study compiled individual interviews and focus groups interviews with engine crew members where they were asked to elaborate on the psychosocial work environment and the major changes in the working conditions on board. Engine crew describes a work situation where they feel a lack of resources. The content of the work has changed, staffing has been reduced, new tasks are being added but the organization of the crew and the design of the work place remains unaltered. Copyright © 2016 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Comparative Performance Assessment of 5kW-Class Solid Oxide Fuel Cell Engines Integrated With Single/Dual-Spool Turbochargers

DTIC Science & Technology

2011-01-01

Comparative Performance Assessment of 5kW-Class Solid Oxide Fuel Cell Engines Integrated with Single/Dual-Spool Turbochargers So-Ryeok Oh, Jing Sun... Turbochargers 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT... fundamental operating regime to the part load performance. Two different mechanical designs are assumed: dual shaft and single shaft as the compressor

Small Engine Technology (SET) Task 24 Business and Regional Aircraft System Studies

NASA Technical Reports Server (NTRS)

Lieber, Lysbeth

2003-01-01

This final report has been prepared by Honeywell Engines & Systems, Phoenix, Arizona, a unit of Honeywell International Inc., documenting work performed during the period June 1999 through December 1999 for the National Aeronautics and Space Administration (NASA) Glenn Research Center, Cleveland, Ohio, under the Small Engine Technology (SET) Program, Contract No. NAS3-27483, Task Order 24, Business and Regional Aircraft System Studies. The work performed under SET Task 24 consisted of evaluating the noise reduction benefits compared to the baseline noise levels of representative 1992 technology aircraft, obtained by applying different combinations of noise reduction technologies to five business and regional aircraft configurations. This report focuses on the selection of the aircraft configurations and noise reduction technologies, the prediction of noise levels for those aircraft, and the comparison of the noise levels with those of the baseline aircraft.

Predicting on-site environmental impacts of municipal engineering works

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

Gangolells, Marta, E-mail: marta.gangolells@upc.edu; Casals, Miquel, E-mail: miquel.casals@upc.edu; Forcada, Núria, E-mail: nuria.forcada@upc.edu

2014-01-15

The research findings fill a gap in the body of knowledge by presenting an effective way to evaluate the significance of on-site environmental impacts of municipal engineering works prior to the construction stage. First, 42 on-site environmental impacts of municipal engineering works were identified by means of a process-oriented approach. Then, 46 indicators and their corresponding significance limits were determined on the basis of a statistical analysis of 25 new-build and remodelling municipal engineering projects. In order to ensure the objectivity of the assessment process, direct and indirect indicators were always based on quantitative data from the municipal engineering projectmore » documents. Finally, two case studies were analysed and found to illustrate the practical use of the proposed model. The model highlights the significant environmental impacts of a particular municipal engineering project prior to the construction stage. Consequently, preventive actions can be planned and implemented during on-site activities. The results of the model also allow a comparison of proposed municipal engineering projects and alternatives with respect to the overall on-site environmental impact and the absolute importance of a particular environmental aspect. These findings are useful within the framework of the environmental impact assessment process, as they help to improve the identification and evaluation of on-site environmental aspects of municipal engineering works. The findings may also be of use to construction companies that are willing to implement an environmental management system or simply wish to improve on-site environmental performance in municipal engineering projects. -- Highlights: • We present a model to predict the environmental impacts of municipal engineering works. • It highlights significant on-site environmental impacts prior to the construction stage. • Findings are useful within the environmental impact assessment process. • They also help contractors to implement environmental management systems.« less

Work production of quantum rotor engines

NASA Astrophysics Data System (ADS)

Seah, Stella; Nimmrichter, Stefan; Scarani, Valerio

2018-04-01

We study the mechanical performance of quantum rotor heat engines in terms of common notions of work using two prototypical models: a mill driven by the heat flow from a hot to a cold mode, and a piston driven by the alternate heating and cooling of a single working mode. We evaluate the extractable work in terms of ergotropy, the kinetic energy associated to net directed rotation, as well as the intrinsic work based on the exerted torque under autonomous operation, and we compare them to the energy output for the case of an external dissipative load and for externally driven engine cycles. Our results connect work definitions from both physical and information-theoretical perspectives. In particular, we find that apart from signatures of angular momentum quantization, the ergotropy is consistent with the intuitive notion of work in the form of net directed motion. It also agrees with the energy output to an external load or agent under optimal conditions. This sets forth a consistent thermodynamical description of rotating quantum motors, flywheels, and clocks.

Experimental study of quasi-periodic on-off phenomena in a small-scale traveling wave thermoacoustic heat engine

NASA Astrophysics Data System (ADS)

Chen, M.; Ju, Y. L.

2017-07-01

Periodic and spontaneous on-off oscillation belongs to the onset and damping behaviors of thermoacoustic engines, and investigations on this phenomenon lead to better operation of the thermoacoustic engines with stable performances. In this paper, the quasi- periodic on-off oscillation in a small-scale traveling wave thermoacoustic heat engine with a resonator length of only 1 m was experimentally investigated. The type of working media, mean pressure and the input heating power are the main operating parameters, which significantly affect the formation of the periodic on-off oscillation. The experimental results demonstrated there was a critical charge pressure over which the periodic on-off oscillation could happen. For the small- scale engine with helium gas as the working media, the mean pressure threshold value was about 1.4 MPa and the on-off oscillation occurred with a single frequency. Using nitrogen and argon gas as the working media, the on-off oscillation was not observed. The reason was qualitatively analyzed as well.

Improvement Design of Parabolic Trough

NASA Astrophysics Data System (ADS)

Ihsan, S. I.; Safian, M. A. I. M.; Taufek, M. A. M.; Mohiuddin, A. K. M.

2017-03-01

The performance of parabolic trough solar collector (PTSC) has been evaluated using different heat transfer working fluids; namely water and SAE20 W50 engine oil. New and slightly improved PTSC was developed to run the experimental study. Under the meteorological conditions of Malaysia, authors found that PTSC can operate at a higher temperature than water collector but the performance efficiency of collector using engine oil is much lower than the water collector.

Maintaining the program balance, volumes 1 and 2

NASA Technical Reports Server (NTRS)

Finger, Harold

1991-01-01

In March of 1990, the NASA Administrator asked the Academy to perform a study to address the following questions: (1) has NASA contracted too much of its technical work; (2) has NASA's in-house technical capability eroded over time; (3) is in-house engineering and scientific work important to the development of scientists and engineers; and (4) is NASA still able to attract quality scientists and engineers. A panel from the Academy addressed each question separately and came up with the following recommendations: (1) prepare and issue guidance on technical functional areas reserved for in-house performance; (2) convert contracted technical functions to in-house performance if critical to agency programs; (3) provide policy guidance to the centers to retain in-house projects; (4) examine the project mix at each center against agency goals and objectives; (5) institute an annual critical review for all technical disciplines; (6) modify the agency's contractor accountability process; and (7) seek opportunities for greater delegation of resources and technical decision making.

Summary of Results from Space Shuttle Main Engine Off-Nominal Testing

NASA Technical Reports Server (NTRS)

Horton, James F.; Megivern, Jeffrey M.; McNutt, Leslie M.

2011-01-01

This paper is a summary of Space Shuttle Main Engine (SSME) off-nominal testing that occurred during 2008 and 2009. During the last two years of planned SSME testing at Stennis Space Center, Pratt & Whitney Rocketdyne worked with their NASA MSFC customer to systematically identify, develop, assess, and implement challenging test objectives in order to expand the knowledge of one of the world s most reliable and highly tested large rocket engine. The objectives successfully investigated three main areas of interest expanding engine performance margins, demonstrating system operational capabilities, and establishing ground work for new rocket engine technology. The testing gave the Space Shuttle Program new options to safely fly out the flight manifest and provided Pratt & Whitney Rocketdyne and NASA new insight into the operational capabilities of the SSME, capabilities which can be used in assessing potential future applications of the RS-25 engine.

Experimental investigation of a multicylinder unmodified diesel engine performance, emission, and heat loss characteristics using different biodiesel blends: rollout of B10 in Malaysia.

PubMed

Abedin, M J; Masjuki, H H; Kalam, M A; Varman, M; Arbab, M I; Fattah, I M Rizwanul; Masum, B M

2014-01-01

This paper deals with the performance and emission analysis of a multicylinder diesel engine using biodiesel along with an in-depth analysis of the engine heat losses in different subsystems followed by the energy balance of all the energy flows from the engine. Energy balance analysis allows the designer to appraise the internal energy variations of a thermodynamic system as a function of ''energy flows" across the control volume as work or heat and also the enthalpies associated with the energy flows which are passing through these boundaries. Palm and coconut are the two most potential biodiesel feed stocks in this part of the world. The investigation was conducted in a four-cylinder diesel engine fuelled with 10% and 20% blends of palm and coconut biodiesels and compared with B5 at full load condition and in the speed range of 1000 to 4000 RPM. Among the all tested blends, palm blends seemed more promising in terms of engine performance, emission, and heat losses. The influence of heat losses on engine performance and emission has been discussed thoroughly in this paper.

Thermodynamic feature of a Brownian heat engine operating between two heat baths.

PubMed

Asfaw, Mesfin

2014-01-01

A generalized theory of nonequilibrium thermodynamics for a Brownian motor operating between two different heat baths is presented. Via a simple paradigmatic model, we not only explore the thermodynamic feature of the engine in the regime of the nonequilibrium steady state but also study the short time behavior of the system for either the isothermal case with load or, in general, the nonisothermal case with or without load. Many elegant thermodynamic theories can be checked via the present model. Furthermore the dependence of the velocity, the efficiency, and the performance of the refrigerator on time t is examined. Our study reveals a current reversal due to time t. In the early system relaxation period, the model works neither as a heat engine nor as a refrigerator and only after a certain period of time does the model start functioning as a heat engine or as a refrigerator. The performance of the engine also improves with time and at steady state the engine manifests a higher efficiency or performance as a refrigerator. Furthermore the effect of energy exchange via the kinetic energy on the performance of the heat engine is explored.

Experimental Investigation of a Multicylinder Unmodified Diesel Engine Performance, Emission, and Heat Loss Characteristics Using Different Biodiesel Blends: Rollout of B10 in Malaysia

PubMed Central

Abedin, M. J.; Masjuki, H. H.; Kalam, M. A.; Varman, M.; Arbab, M. I.; Fattah, I. M. Rizwanul; Masum, B. M.

2014-01-01

This paper deals with the performance and emission analysis of a multicylinder diesel engine using biodiesel along with an in-depth analysis of the engine heat losses in different subsystems followed by the energy balance of all the energy flows from the engine. Energy balance analysis allows the designer to appraise the internal energy variations of a thermodynamic system as a function of ‘‘energy flows” across the control volume as work or heat and also the enthalpies associated with the energy flows which are passing through these boundaries. Palm and coconut are the two most potential biodiesel feed stocks in this part of the world. The investigation was conducted in a four-cylinder diesel engine fuelled with 10% and 20% blends of palm and coconut biodiesels and compared with B5 at full load condition and in the speed range of 1000 to 4000 RPM. Among the all tested blends, palm blends seemed more promising in terms of engine performance, emission, and heat losses. The influence of heat losses on engine performance and emission has been discussed thoroughly in this paper. PMID:25162046

Rocket-Based Combined Cycle Engine Concept Development

NASA Technical Reports Server (NTRS)

Ratekin, G.; Goldman, Allen; Ortwerth, P.; Weisberg, S.; McArthur, J. Craig (Technical Monitor)

2001-01-01

The development of rocket-based combined cycle (RBCC) propulsion systems is part of a 12 year effort under both company funding and contract work. The concept is a fixed geometry integrated rocket, ramjet, scramjet, which is hydrogen fueled and uses hydrogen regenerative cooling. The baseline engine structural configuration uses an integral structure that eliminates panel seals, seal purge gas, and closeout side attachments. Engine A5 is the current configuration for NASA Marshall Space Flight Center (MSFC) for the ART program. Engine A5 models the complete flight engine flowpath of inlet, isolator, airbreathing combustor, and nozzle. High-performance rocket thrusters are integrated into the engine enabling both low speed air-augmented rocket (AAR) and high speed pure rocket operation. Engine A5 was tested in GASL's new Flight Acceleration Simulation Test (FAST) facility in all four operating modes, AAR, RAM, SCRAM, and Rocket. Additionally, transition from AAR to RAM and RAM to SCRAM was also demonstrated. Measured performance demonstrated vision vehicle performance levels for Mach 3 AAR operation and ramjet operation from Mach 3 to 4. SCRAM and rocket mode performance was above predictions. For the first time, testing also demonstrated transition between operating modes.

Materials-Enabled High-Efficiency (MEHE) Heavy-Duty Diesel Engines

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

Kass, M.; Veliz, M.

2011-09-30

The purpose of this Cooperative Research and Development Agreement (CRADA) between UTBattelle, Inc. and Caterpillar, Inc. was to improve diesel engine efficiency by incorporating advanced materials to enable higher combustion pressures and temperatures necessary for improved combustion. The project scope also included novel materials for use in advanced components and designs associated with waste-heat recovery and other concepts for improved thermal efficiency. Caterpillar initially provided ORNL with a 2004 Tier 2 C15 ACERT diesel engine (designed for on-highway use) and two 600 hp motoring dynamometers. The first year of the CRADA effort was focused on establishing a heavy-duty experimental enginemore » research cell. First year activities included procuring, installing and commissioning the cell infrastructure. Infrastructure components consisted of intake air handling system, water tower, exhaust handling system, and cell air conditioning. Other necessary infrastructure items included the fuel delivery system and bottled gas handling to support the analytical instrumentation. The second year of the CRADA focused on commissioning the dynamometer system to enable engine experimentation. In addition to the requirements associated with the dynamometer controller, the electrical system needed a power factor correction system to maintain continuity with the electrical grid. During the second year the engine was instrumented and baseline operated to confirm performance and commission the dynamometer. The engine performance was mapped and modeled according to requirements provided by Caterpillar. This activity was further supported by a Work-for-Others project from Caterpillar to evaluate a proprietary modeling system. A second Work-for-Others activity was performed to evaluate a novel turbocharger design. This project was highly successful and may lead to new turbocharger designs for Caterpillar heavy-duty diesel engines. During the third (and final) year of the CRADA, a novel valve material was evaluated to assess high temperature performance and durability. A series of prototype valves, composed of a unique nickel-alloy was placed in the engine head. The engine was aggressively operated using a transient test cycle for 200 hours. The valve recession was periodically measured to determine valve performance. Upon completion of the test the valves were removed and returned to Caterpillar for additional assessment. Industrial in-kind support was available throughout the project period. Review of the status and research results were carried out on a regular basis (meetings and telecons) which included direction for future work activities. A significant portion of the industrial support was in the form of information exchange and technical consultation.« less

Temperature measurement in a gas turbine engine combustor

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

DeSilva, Upul

A method and system for determining a temperature of a working gas passing through a passage to a turbine section of a gas turbine engine. The method includes identifying an acoustic frequency at a first location in the engine upstream from the turbine section, and using the acoustic frequency for determining a first temperature value at the first location that is directly proportional to the acoustic frequency and a calculated constant value. A second temperature of the working gas is determined at a second location in the engine and, using the second temperature, a back calculation is performed to determinemore » a temperature value for the working gas at the first location. The first temperature value is compared to the back calculated temperature value to change the calculated constant value to a recalculated constant value. Subsequent first temperature values at the first location may be determined based on the recalculated constant value.« less

A Critical Examination of the Construct Validity of the TTI Performance DNA[TM] Survey for the Purpose of Differentiating the Entrepreneurially-Minded Engineer

ERIC Educational Resources Information Center

Dietrich, Sandra L.

2012-01-01

The United States needs workers with more than technical skills to meet the demands of global competition; more specifically, a new breed of engineer is necessary, one who possesses leadership skills and business acumen in addition to the technical engineering skills. One Midwestern foundation has recognized this challenge and is working with…

Stability Analysis of Distributed Engine Control Systems Under Communication Packet Drop (Postprint)

DTIC Science & Technology

2008-07-01

use, modify, reproduce, release, perform, display, or disclose the work. 14. ABSTRACT Currently, Full Authority Digital Engine Control ( FADEC ...based on a centralized architecture framework is being widely used for gas turbine engine control. However, current FADEC is not able to meet the...system (DEC). FADEC based on Distributed Control Systems (DCS) offers modularity, improved control systems prognostics and fault tolerance along with

Improving Space Project Cost Estimating with Engineering Management Variables

NASA Technical Reports Server (NTRS)

Hamaker, Joseph W.; Roth, Axel (Technical Monitor)

2001-01-01

Current space project cost models attempt to predict space flight project cost via regression equations, which relate the cost of projects to technical performance metrics (e.g. weight, thrust, power, pointing accuracy, etc.). This paper examines the introduction of engineering management parameters to the set of explanatory variables. A number of specific engineering management variables are considered and exploratory regression analysis is performed to determine if there is statistical evidence for cost effects apart from technical aspects of the projects. It is concluded that there are other non-technical effects at work and that further research is warranted to determine if it can be shown that these cost effects are definitely related to engineering management.

Evaluation of ceramics for stator application: Gas turbine engine report

NASA Technical Reports Server (NTRS)

Trela, W.; Havstad, P. H.

1978-01-01

Current ceramic materials, component fabrication processes, and reliability prediction capability for ceramic stators in an automotive gas turbine engine environment are assessed. Simulated engine duty cycle testing of stators conducted at temperatures up to 1093 C is discussed. Materials evaluated are SiC and Si3N4 fabricated from two near-net-shape processes: slip casting and injection molding. Stators for durability cycle evaluation and test specimens for material property characterization, and reliability prediction model prepared to predict stator performance in the simulated engine environment are considered. The status and description of the work performed for the reliability prediction modeling, stator fabrication, material property characterization, and ceramic stator evaluation efforts are reported.

V & V Within Reuse-Based Software Engineering

NASA Technical Reports Server (NTRS)

Addy, Edward A.

1996-01-01

Verification and validation (V&V) is used to increase the level of assurance of critical software, particularly that of safety-critical and mission critical software. This paper describes the working group's success in identifying V&V tasks that could be performed in the domain engineering and transition levels of reuse-based software engineering. The primary motivation for V&V at the domain level is to provide assurance that the domain requirements are correct and that the domain artifacts correctly implement the domain requirements. A secondary motivation is the possible elimination of redundant V&V activities at the application level. The group also considered the criteria and motivation for performing V&V in domain engineering.

Initial test results from a prototype, 20 kW helium charged Stirling engine

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

Clarke, M.A.; Taylor, D.R.

An alpha-configuration, helium charged Stirling engine with a predicted output of 20 kW indicated power has been developed by a British consortium of universities and industrial companies. The work performed by the Royal Naval Engineering College has been in computer assisted design and component testing, with future plans for full engine trials during 1984/85. The scope of this paper is to outline the data obtained during motoring trials of the engine block and crankcase assembly, together with details of modifications incorporated in the various components.

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

Pawlowski, Alexander; Splitter, Derek A

It is well known that spark ignited engine performance and efficiency is closely coupled to fuel octane number. The present work combines historical and recent trends in spark ignition engines to build a database of engine design, performance, and fuel octane requirements over the past 80 years. The database consists of engine compression ratio, required fuel octane number, peak mean effective pressure, specific output, and combined unadjusted fuel economy for passenger vehicles and light trucks. Recent trends in engine performance, efficiency, and fuel octane number requirement were used to develop correlations of fuel octane number utilization, performance, specific output. Themore » results show that historically, engine compression ratio and specific output have been strongly coupled to fuel octane number. However, over the last 15 years the sales weighted averages of compression ratios, specific output, and fuel economy have increased, while the fuel octane number requirement has remained largely unchanged. Using the developed correlations, 10-year-out projections of engine performance, design, and fuel economy are estimated for various fuel octane numbers, both with and without turbocharging. The 10-year-out projection shows that only by keeping power neutral while using 105 RON fuel will allow the vehicle fleet to meet CAFE targets if only the engine is relied upon to decrease fuel consumption. If 98 RON fuel is used, a power neutral fleet will have to reduce vehicle weight by 5%.« less

Decision Support System Requirements Definition for Human Extravehicular Activity Based on Cognitive Work Analysis

PubMed Central

Miller, Matthew James; McGuire, Kerry M.; Feigh, Karen M.

2016-01-01

The design and adoption of decision support systems within complex work domains is a challenge for cognitive systems engineering (CSE) practitioners, particularly at the onset of project development. This article presents an example of applying CSE techniques to derive design requirements compatible with traditional systems engineering to guide decision support system development. Specifically, it demonstrates the requirements derivation process based on cognitive work analysis for a subset of human spaceflight operations known as extravehicular activity. The results are presented in two phases. First, a work domain analysis revealed a comprehensive set of work functions and constraints that exist in the extravehicular activity work domain. Second, a control task analysis was performed on a subset of the work functions identified by the work domain analysis to articulate the translation of subject matter states of knowledge to high-level decision support system requirements. This work emphasizes an incremental requirements specification process as a critical component of CSE analyses to better situate CSE perspectives within the early phases of traditional systems engineering design. PMID:28491008

Decision Support System Requirements Definition for Human Extravehicular Activity Based on Cognitive Work Analysis.

PubMed

Miller, Matthew James; McGuire, Kerry M; Feigh, Karen M

2017-06-01

The design and adoption of decision support systems within complex work domains is a challenge for cognitive systems engineering (CSE) practitioners, particularly at the onset of project development. This article presents an example of applying CSE techniques to derive design requirements compatible with traditional systems engineering to guide decision support system development. Specifically, it demonstrates the requirements derivation process based on cognitive work analysis for a subset of human spaceflight operations known as extravehicular activity . The results are presented in two phases. First, a work domain analysis revealed a comprehensive set of work functions and constraints that exist in the extravehicular activity work domain. Second, a control task analysis was performed on a subset of the work functions identified by the work domain analysis to articulate the translation of subject matter states of knowledge to high-level decision support system requirements. This work emphasizes an incremental requirements specification process as a critical component of CSE analyses to better situate CSE perspectives within the early phases of traditional systems engineering design.

Study on Fault Diagnostics of a Turboprop Engine Using Inverse Performance Model and Artificial Intelligent Methods

NASA Astrophysics Data System (ADS)

Kong, Changduk; Lim, Semyeong

2011-12-01

Recently, the health monitoring system of major gas path components of gas turbine uses mostly the model based method like the Gas Path Analysis (GPA). This method is to find quantity changes of component performance characteristic parameters such as isentropic efficiency and mass flow parameter by comparing between measured engine performance parameters such as temperatures, pressures, rotational speeds, fuel consumption, etc. and clean engine performance parameters without any engine faults which are calculated by the base engine performance model. Currently, the expert engine diagnostic systems using the artificial intelligent methods such as Neural Networks (NNs), Fuzzy Logic and Genetic Algorithms (GAs) have been studied to improve the model based method. Among them the NNs are mostly used to the engine fault diagnostic system due to its good learning performance, but it has a drawback due to low accuracy and long learning time to build learning data base if there are large amount of learning data. In addition, it has a very complex structure for finding effectively single type faults or multiple type faults of gas path components. This work builds inversely a base performance model of a turboprop engine to be used for a high altitude operation UAV using measured performance data, and proposes a fault diagnostic system using the base engine performance model and the artificial intelligent methods such as Fuzzy logic and Neural Network. The proposed diagnostic system isolates firstly the faulted components using Fuzzy Logic, then quantifies faults of the identified components using the NN leaned by fault learning data base, which are obtained from the developed base performance model. In leaning the NN, the Feed Forward Back Propagation (FFBP) method is used. Finally, it is verified through several test examples that the component faults implanted arbitrarily in the engine are well isolated and quantified by the proposed diagnostic system.

Neutron and gamma (density) logging in welded tuff

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

Lin, W

This Technical Implementation Procedure (TIP) describes the field operation, and the management of data records pertaining to neutron logging and density logging in welded tuff. This procedure applies to all borehole surveys performed in support of Engineered Barrier System Field Tests (EBSFT), including the Earge Block Tests (LBT) and Initial Engineered Barrier System Field Tests (IEBSFT) - WBS 1.2.3.12.4. The purpose of this TIP is to provide guidelines so that other equally trained and qualified personnel can understand how the work is performed or how to repeat the work if needed. The work will be documented by the use ofmore » Scientific Notebooks (SNs) as discussed in 033-YMP-QP 3.4. The TIP will provide a set of guidelines which the scientists will take into account in conducting the mea- surements. The use of this TIP does not imply that this is repetitive work that does not require profes- sional judgment.« less

National Dam Safety Program. Wallace Lake Dam (MO 31263), White River Basin, Carter County, Missouri. Phase I Inspection Report.

DTIC Science & Technology

1980-08-01

ARMY ENGINEER DISTRICT, ST. LOUIS D I Ms FOPATE OF MISSOURI E L E C T p D3 AUGUST, 19ue pTE4ENA lo1 9 o85 UNCLASSIFIED SECURITY CLASSIFICATION OF THIS...Anderson Engineering, Inc. DACW4 3-8,0-C-A673 9 . PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGJAM EL"gNT. PROJ&QT. TASK U.S. Army Engineer District...the-work-reported was accomplished. Leave blank in in-house reports. Block 9 . Performing Organization Name and Address. For in-house reports enter the

Flight testing the digital electronic engine control in the F-15 airplane

NASA Technical Reports Server (NTRS)

Myers, L. P.

1984-01-01

The digital electronic engine control (DEEC) is a full-authority digital engine control developed for the F100-PW-100 turbofan engine which was flight tested on an F-15 aircraft. The DEEC hardware and software throughout the F-15 flight envelope was evaluated. Real-time data reduction and data display systems were implemented. New test techniques and stronger coordination between the propulsion test engineer and pilot were developed which produced efficient use of test time, reduced pilot work load, and greatly improved quality data. The engine pressure ratio (EPR) control mode is demonstrated. It is found that the nonaugmented throttle transients and engine performance are satisfactory.

The Electrical Engineering Profession at NASA

NASA Technical Reports Server (NTRS)

Emerson, Dawn

2004-01-01

Presentation given at the opening ceremony of the Centre of Vocational Excellence in Birmingham, England on October 7, 2004. Presentation highlights examples of work performed by Electrical Engineers at the NASA Glenn Research Center and highlights the demographics of the NASA workforce. Presentation is intended to be inspirational in nature.

Evaluating Games-Based Learning

ERIC Educational Resources Information Center

Hainey, Thomas; Connolly, Thomas

2010-01-01

A highly important part of software engineering education is requirements collection and analysis, one of the initial stages of the Software Development Lifecycle. No other conceptual work is as difficult to rectify at a later stage or as damaging to the overall system if performed incorrectly. As software engineering is a field with a reputation…

Stirling engine design manual

NASA Technical Reports Server (NTRS)

Martini, W. R.

1978-01-01

This manual is intended to serve both as an introduction to Stirling engine analysis methods and as a key to the open literature on Stirling engines. Over 800 references are listed and these are cross referenced by date of publication, author and subject. Engine analysis is treated starting from elementary principles and working through cycles analysis. Analysis methodologies are classified as first, second or third order depending upon degree of complexity and probable application; first order for preliminary engine studies, second order for performance prediction and engine optimization, and third order for detailed hardware evaluation and engine research. A few comparisons between theory and experiment are made. A second order design procedure is documented step by step with calculation sheets and a worked out example to follow. Current high power engines are briefly described and a directory of companies and individuals who are active in Stirling engine development is included. Much remains to be done. Some of the more complicated and potentially very useful design procedures are now only referred to. Future support will enable a more thorough job of comparing all available design procedures against experimental data which should soon be available.

Development and applications of various optimization algorithms for diesel engine combustion and emissions optimization

NASA Astrophysics Data System (ADS)

Ogren, Ryan M.

For this work, Hybrid PSO-GA and Artificial Bee Colony Optimization (ABC) algorithms are applied to the optimization of experimental diesel engine performance, to meet Environmental Protection Agency, off-road, diesel engine standards. This work is the first to apply ABC optimization to experimental engine testing. All trials were conducted at partial load on a four-cylinder, turbocharged, John Deere engine using neat-Biodiesel for PSO-GA and regular pump diesel for ABC. Key variables were altered throughout the experiments, including, fuel pressure, intake gas temperature, exhaust gas recirculation flow, fuel injection quantity for two injections, pilot injection timing and main injection timing. Both forms of optimization proved effective for optimizing engine operation. The PSO-GA hybrid was able to find a superior solution to that of ABC within fewer engine runs. Both solutions call for high exhaust gas recirculation to reduce oxide of nitrogen (NOx) emissions while also moving pilot and main fuel injections to near top dead center for improved tradeoffs between NOx and particulate matter.

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

Shao, Huifang; Lam, William; Remias, Joseph

Mobile source emissions standards are becoming more stringent and particulate emissions from gasoline direct injection (GDI) engines represent a particular challenge. Gasoline particulate filter (GPF) is deemed as one possible technical solution for particulate emissions reduction. In this work, a study was conducted on eight formulations of lubricants to determine their effect on GDI engine particulate emissions and GPF performance. Accelerated ash loading tests were conducted on a 2.4L GDI engine with engine oil injection in gasoline fuel by 2%. The matrix of eight formulations was designed with changing levels of sulfated ash (SASH) level, Zinc dialkyldithiophosphates (ZDDP) level andmore » detergent type. Comprehensive evaluations of particulates included mass, number, size distribution, composition, morphology and soot oxidation properties. GPF performance was assessed through filtration efficiency, back pressure and morphology. It was determined that oil formulation affects the particulate emission characteristics and subsequent GPF performance.« less

CF60 Concrete Composition Design and Application on Fudiankou Xijiang Super Large Bridge

NASA Astrophysics Data System (ADS)

Qiu, Yi Mei; Wen, Sen Yuan; Chen, Jun Xiang

2018-06-01

Guangxi Wuzhou City Ring Road Fudiankou Xijiang super large bridge CF60 concrete is a new multi-phase composite high-performance concrete, this paper for the Fudiankou Xijiang bridge structure and characteristics of the project, in accordance with the principle of local materials and technical specification requirements, combined with the site conditions of CF60 engineering high performance concrete component materials, proportion and the technical performance, quantify the main physical and mechanical performance index. Analysis main influencing factors of the technical indicators, reasonable adjustment of concrete mix design parameters, and the use of technical means of admixture and multi-function composite admixture of concrete, obtain the optimal proportion of good work, process, mechanical properties stability and durability of engineering properties, recommend and verification of concrete mix; to explore the CF60 high performance concrete Soil in the Fudiankou Xijiang bridge application technology, detection and tracking the quality of concrete construction, concrete structure during the construction of the key technology and control points is proposed, evaluation of CF60 high performance concrete in the actual engineering application effect and benefit to ensure engineering quality of bridge structure and service life, and super long span bridge engineering construction to provide basis and reference.

Engineers Work on the James Webb Space Telescope

NASA Image and Video Library

2017-12-08

Engineers at Ball Aerospace test the Wavefront Sensing and Control testbed to ensure that the 18 primary mirror segments and one secondary mirror on JWST work as one. The test is performed on a 1/6 scale model of the JWST mirrors. Credit: NASA/Northrop Grumman/Ball Aerospace To read more about the James Webb Space Telescope go to: www.nasa.gov/topics/technology/features/partnerships.html NASA Goddard Space Flight Center is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

Hubble Space Telescope Design Engineering Knowledgebase (HSTDEK)

NASA Technical Reports Server (NTRS)

Johannes, James D.; Everetts, Clark

1989-01-01

The research covered here pays specific attention to the development of tools to assist knowledge engineers in acquiring knowledge and to assist other technical, engineering, and management personnel in automatically performing knowledge capture as part of their everyday work without adding any extra work to what they already do. Requirements for data products, the knowledge base, and methods for mapping knowledge in the documents onto the knowledge representations are discussed, as are some of the difficulties of capturing in the knowledge base the structure of the design process itself, along with a model of the system designed. The capture of knowledge describing the interactions of different components is also discussed briefly.

Comparison of free-piston Stirling engine model predictions with RE1000 engine test data

NASA Technical Reports Server (NTRS)

Tew, R. C., Jr.

1984-01-01

Predictions of a free-piston Stirling engine model are compared with RE1000 engine test data taken at NASA-Lewis Research Center. The model validation and the engine testing are being done under a joint interagency agreement between the Department of Energy's Oak Ridge National Laboratory and NASA-Lewis. A kinematic code developed at Lewis was upgraded to permit simulation of free-piston engine performance; it was further upgraded and modified at Lewis and is currently being validated. The model predicts engine performance by numerical integration of equations for each control volume in the working space. Piston motions are determined by numerical integration of the force balance on each piston or can be specified as Fourier series. In addition, the model Fourier analyzes the various piston forces to permit the construction of phasor force diagrams. The paper compares predicted and experimental values of power and efficiency and shows phasor force diagrams for the RE1000 engine displacer and piston. Further development plans for the model are also discussed.

Wave-Rotor-Enhanced Gas Turbine Engine Demonstrator

NASA Technical Reports Server (NTRS)

Welch, Gerard E.; Paxson, Daniel E.; Wilson, Jack; Synder, Philip H.

1999-01-01

The U.S. Army Research Laboratory, NASA Glenn Research Center, and Rolls-Royce Allison are working collaboratively to demonstrate the benefits and viability of a wave-rotor-topped gas turbine engine. The self-cooled wave rotor is predicted to increase the engine overall pressure ratio and peak temperature by 300% and 25 to 30%. respectively, providing substantial improvements in engine efficiency and specific power. Such performance improvements would significantly reduce engine emissions and the fuel logistics trails of armed forces. Progress towards a planned demonstration of a wave-rotor-topped Rolls-Royce Allison model 250 engine has included completion of the preliminary design and layout of the engine, the aerodynamic design of the wave rotor component and prediction of its aerodynamic performance characteristics in on- and off-design operation and during transients, and the aerodynamic design of transition ducts between the wave rotor and the high pressure turbine. The topping cycle increases the burner entry temperature and poses a design challenge to be met in the development of the demonstrator engine.

48 CFR 43.203 - Change order accounting procedures.

Code of Federal Regulations, 2011 CFR

2011-10-01

...., engineering costs and costs of obsolete or reperformed work). (2) Costs of added distinct work caused by the...) Contractors' accounting systems are seldom designed to segregate the costs of performing changed work... possible need to revise their accounting procedures to comply with the cost segregation requirements of the...

48 CFR 43.203 - Change order accounting procedures.

Code of Federal Regulations, 2014 CFR

2014-10-01

...., engineering costs and costs of obsolete or reperformed work). (2) Costs of added distinct work caused by the...) Contractors' accounting systems are seldom designed to segregate the costs of performing changed work... possible need to revise their accounting procedures to comply with the cost segregation requirements of the...

48 CFR 43.203 - Change order accounting procedures.

Code of Federal Regulations, 2013 CFR

2013-10-01

...., engineering costs and costs of obsolete or reperformed work). (2) Costs of added distinct work caused by the...) Contractors' accounting systems are seldom designed to segregate the costs of performing changed work... possible need to revise their accounting procedures to comply with the cost segregation requirements of the...

48 CFR 43.203 - Change order accounting procedures.

Code of Federal Regulations, 2012 CFR

2012-10-01

...., engineering costs and costs of obsolete or reperformed work). (2) Costs of added distinct work caused by the...) Contractors' accounting systems are seldom designed to segregate the costs of performing changed work... possible need to revise their accounting procedures to comply with the cost segregation requirements of the...

Complete modeling for systems of a marine diesel engine

NASA Astrophysics Data System (ADS)

Nahim, Hassan Moussa; Younes, Rafic; Nohra, Chadi; Ouladsine, Mustapha

2015-03-01

This paper presents a simulator model of a marine diesel engine based on physical, semi-physical, mathematical and thermodynamic equations, which allows fast predictive simulations. The whole engine system is divided into several functional blocks: cooling, lubrication, air, injection, combustion and emissions. The sub-models and dynamic characteristics of individual blocks are established according to engine working principles equations and experimental data collected from a marine diesel engine test bench for SIMB Company under the reference 6M26SRP1. The overall engine system dynamics is expressed as a set of simultaneous algebraic and differential equations using sub-blocks and S-Functions of Matlab/Simulink. The simulation of this model, implemented on Matlab/Simulink has been validated and can be used to obtain engine performance, pressure, temperature, efficiency, heat release, crank angle, fuel rate, emissions at different sub-blocks. The simulator will be used, in future work, to study the engine performance in faulty conditions, and can be used to assist marine engineers in fault diagnosis and estimation (FDI) as well as designers to predict the behavior of the cooling system, lubrication system, injection system, combustion, emissions, in order to optimize the dimensions of different components. This program is a platform for fault simulator, to investigate the impact on sub-blocks engine's output of changing values for faults parameters such as: faulty fuel injector, leaky cylinder, worn fuel pump, broken piston rings, a dirty turbocharger, dirty air filter, dirty air cooler, air leakage, water leakage, oil leakage and contamination, fouling of heat exchanger, pumps wear, failure of injectors (and many others).

High Speed Prototype Car Test

NASA Image and Video Library

2014-01-10

CAPE CANAVERAL, Fla. - An engineer readies a Hennessey Venom GT for test runs on the 3.5-mile long runway at the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. The flat concrete runway is one of the few places in the world where high performance automobiles can be tested for aerodynamic and safety designs. Hennessey Performance of Sealy, Texas, worked with Performance Power Racing in West Palm Beach to arrange use of the NASA facility. Performance Power Racing has conducted numerous engineering tests on the runway with a variety of vehicles. Photo credit: NASA/Kim Shiflett

High Speed Prototype Car Test

NASA Image and Video Library

2014-01-10

CAPE CANAVERAL, Fla. - Mechanics, engineers and Driver Brian Smith, in jumpsuit, ready a Hennessey Venom GT for test runs on the 3.5-mile long runway at the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. The flat concrete runway is one of the few places in the world where high performance automobiles can be tested for aerodynamic and safety designs. Hennessey Performance of Sealy, Texas, worked with Performance Power Racing in West Palm Beach to arrange use of the NASA facility. Performance Power Racing has conducted numerous engineering tests on the runway with a variety of vehicles. Photo credit: NASA/Kim Shiflett

High Speed Prototype Car Test

NASA Image and Video Library

2014-01-10

CAPE CANAVERAL, Fla. - Mechanics and engineers ready a Hennessey Venom GT for test runs on the 3.5-mile long runway at the Shuttle Landing Facility at NASA's Kennedy Space Center in Florida. The flat concrete runway is one of the few places in the world where high performance automobiles can be tested for aerodynamic and safety designs. Hennessey Performance of Sealy, Texas, worked with Performance Power Racing in West Palm Beach to arrange use of the NASA facility. Performance Power Racing has conducted numerous engineering tests on the runway with a variety of vehicles. Photo credit: NASA/Kim Shiflett

Performance Optimization of Storable Bipropellant Engines to Fully Exploit Advanced Material Technologies

NASA Technical Reports Server (NTRS)

Miller, Scott; Henderson, Scott; Portz, Ron; Lu, Frank; Wilson, Kim; Krismer, David; Alexander, Leslie; Chapman, Jack; England, Chris

2007-01-01

This paper summarizes the work performed to dale on the NASA Cycle 3A Advanced Chemical Propulsion Technology Program. The primary goals of the program are to design, fabricate, and test high performance bipropellant engines using iridium/rhenium chamber technology to obtain 335 seconds specific impulse with nitrogen tetroxide/hydrazine propellants and 330 seconds specific impulse with nitrogen tetroxide/monomethylhydrazine propellants. Aerojet has successfully completed the Base Period of this program, wherein (1) mission and system studies have been performed to verify system performance benefits and to determine engine physical and operating parameters, (2) preliminary chamber and nozzle designs have been completed and a chamber supplier has been downselected, (3) high temperature, high pressure off-nominal hot fire testing of an existing state-of-the-art high performance bipropellant engine has been completed, and (4) thermal and performance data from the engine test have been correlated with new thermal models to enable design of the new engine injector and injector/chamber interface. In the next phase of the program, Aerojet will complete design, fabrication, and test of the nitrogen tetroxide/hydrazine engine to demonstrate 335 seconds specific impulse, and also investigate improved technologies for iridium/rhenium chamber fabrication. Achievement of the NRA goals will significantly benefit NASA interplanetary missions and other government and commercial opportunities by enabling reduced launch weight and/or increased payload. At the conclusion of the program, the objective is to have an engine ready for final design and qualification for a specific science mission or commercial application. The program also constitutes a stepping stone to future, development, such as higher pressure pump-fed in-space storable engines.

Review on factors affecting the performance of pulse detonation engine

NASA Astrophysics Data System (ADS)

Tripathi, Saurabh; Pandey, Krishna Murari

2018-04-01

Now a day's rocket engines (air-breathing type) are being used for aerospace purposes but the studies have shown that these are less efficient, so alternatives are being searched for these. Pulse Detonation Engine (PDE) is one such efficient engine which can replace the rocket engines. In this review paper, different researches have been cited. As can be observed from various researches, insertion of obstacles is better. Deflagration to Detonation(DDT) transition process is found to be most important factor. So a lot of researches are being done considering this DDT chamber. Also, the ignition chamber and ejector were found to improve the effectiveness of PDE. The PDE works with a range of Mach 0-4. Flame acceleration is also found to increase the DDT process. Use of valve and valveless engine has also been compared. Various other factors have been focused in this review paper which is found to boost PDE performance.

2nd Generation Reusable Launch Vehicle (2G RLV). Revised

NASA Technical Reports Server (NTRS)

Matlock, Steve; Sides, Steve; Kmiec, Tom; Arbogast, Tim; Mayers, Tom; Doehnert, Bill

2001-01-01

This is a revised final report and addresses all of the work performed on this program. Specifically, it covers vehicle architecture background, definition of six baseline engine cycles, reliability baseline (space shuttle main engine QRAS), and component level reliability/performance/cost for the six baseline cycles, and selection of 3 cycles for further study. This report further addresses technology improvement selection and component level reliability/performance/cost for the three cycles selected for further study, as well as risk reduction plans, and recommendation for future studies.

Evaluation Program on the Implementation of Industrial Apprenticeship (Prakerin) in Electrical Engineering

NASA Astrophysics Data System (ADS)

Maulana, I.; Sumarto; Nurafiati, P.; Puspita, R. H.

2018-02-01

This research aims to find out the evaluation program of the Industrial apprenticeship (Prakerin) in electrical engineering. This research includes on four variables of CIPP. (1). Context (a). programme planning (b). design. (2). Input (a). readiness of students (b). performance of vocational education teachers (c). Facilities and infrastructure, (3). process (a). performance students (b). performance mentors, (4). Product (a). readiness of student work. This research is a type of program evaluation research with Stake model approach. Data collection methods used are questionnaires with closed questions and frequently asked questions.

Case study: Comparison of motivation for achieving higher performance between self-directed and manager-directed aerospace engineering teams

NASA Astrophysics Data System (ADS)

Erlick, Katherine

"The stereotype of engineers is that they are not people oriented; the stereotype implies that engineers would not work well in teams---that their task emphasis is a solo venture and does not encourage social aspects of collaboration" (Miner & Beyerlein, 1999, p. 16). The problem is determining the best method of providing a motivating environment where design engineers may contribute within a team in order to achieve higher performance in the organization. Theoretically, self-directed work teams perform at higher levels. But, allowing a design engineer to contribute to the team while still maintaining his or her anonymity is the key to success. Therefore, a motivating environment must be established to encourage greater self-actualization in design engineers. The purpose of this study is to determine the favorable motivational environment for design engineers and describe the comparison between two aerospace design-engineering teams: one self-directed and the other manager directed. Following the comparison, this study identified whether self-direction or manager-direction provides the favorable motivational environment for operating as a team in pursuit of achieving higher performance. The methodology used in this research was the case study focusing on the team's levels of job satisfaction and potential for higher performance. The collection of data came from three sources, (a) surveys, (b) researcher observer journal and (c) collection of artifacts. The surveys provided information regarding personal behavior characteristics, potentiality for higher performance and motivational attributes. The researcher journal provided information regarding team dynamics, individual interaction, conflict and conflict resolution. The milestone for performance was based on the collection of artifacts from the two teams. The findings from this study illustrated that whether the team was manager-directed or self-directed does not appear to influence the needs and wants of the team members. The self-directed team was more motivated to learn their topic than was the manager-directed team, but they struggled with their path in following their vision whereas the manager-directed team kept their focus under the guidance of their manager. Finally, both teams are in fact effective; however specific circumstances may be an important objective when deciding to utilize either a self-directed or manager-directed team.

Advanced Gas Turbine (AGT) powertrain system development for automotive applications report

NASA Technical Reports Server (NTRS)

1984-01-01

This report describes progress and work performed during January through June 1984 to develop technology for an Advanced Gas Turbine (AGT) engine for automotive applications. Work performed during the first eight periods initiated design and analysis, ceramic development, component testing, and test bed evaluation. Project effort conducted under this contract is part of the DOE Gas Turbine Highway Vehicle System Program. This program is oriented at providing the United States automotive industry the high-risk long-range techology necessary to produce gas turbine engines for automobiles with reduced fuel consumption and reduced environmental impact. Technology resulting from this program is intended to reach the marketplace by the early 1990s.

Integrated Design and Engineering Analysis (IDEA) Environment - Propulsion Related Module Development and Vehicle Integration

NASA Technical Reports Server (NTRS)

Kamhawi, Hilmi N.

2013-01-01

This report documents the work performed during the period from May 2011 - October 2012 on the Integrated Design and Engineering Analysis (IDEA) environment. IDEA is a collaborative environment based on an object-oriented, multidisciplinary, distributed framework using the Adaptive Modeling Language (AML). This report will focus on describing the work done in the areas of: (1) Integrating propulsion data (turbines, rockets, and scramjets) in the system, and using the data to perform trajectory analysis; (2) Developing a parametric packaging strategy for a hypersonic air breathing vehicles allowing for tank resizing when multiple fuels and/or oxidizer are part of the configuration; and (3) Vehicle scaling and closure strategies.

Work, Productivity, and Human Performance: Practical Case Studies in Ergonomics, Human Factors and Human Engineering.

ERIC Educational Resources Information Center

Fraser, T. M.; Pityn, P. J.

This book contains 12 case histories, each based on a real-life problem, that show how a manager can use common sense, knowledge, and interpersonal skills to solve problems in human performance at work. Each case study describes a worker's problem and provides background information and an assignment; solutions are suggested. The following cases…

KSC-08pd1901

NASA Image and Video Library

2008-07-02

CAPE CANAVERAL, Fla. – Professor Peter Voci, NYIT MOCAP (Motion Capture) team director, (left) hands a component of the Orion Crew Module mockup to one of three technicians inside the mockup. The technicians wear motion capture suits. The motion tracking aims to improve efficiency of assembly processes and identify potential ergonomic risks for technicians assembling the mockup. The work is being performed in United Space Alliance's Human Engineering Modeling and Performance Lab in the RLV Hangar at NASA's Kennedy Space Center. The motion tracking aims to improve efficiency of assembly processes and identify potential ergonomic risks for technicians assembling the mockup. The work is being performed in United Space Alliance's Human Engineering Modeling and Performance Lab in the RLV Hangar at NASA's Kennedy Space Center. Part of NASA's Constellation Program, the Orion spacecraft will return humans to the moon and prepare for future voyages to Mars and other destinations in our solar system.

Embedded image processing engine using ARM cortex-M4 based STM32F407 microcontroller

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

Samaiya, Devesh, E-mail: samaiya.devesh@gmail.com

2014-10-06

Due to advancement in low cost, easily available, yet powerful hardware and revolution in open source software, urge to make newer, more interactive machines and electronic systems have increased manifold among engineers. To make system more interactive, designers need easy to use sensor systems. Giving the boon of vision to machines was never easy, though it is not impossible these days; it is still not easy and expensive. This work presents a low cost, moderate performance and programmable Image processing engine. This Image processing engine is able to capture real time images, can store the images in the permanent storagemore » and can perform preprogrammed image processing operations on the captured images.« less

Ultra-efficient Engine Diameter Study

NASA Technical Reports Server (NTRS)

Daggett, David L.; Brown, Stephen T.; Kawai, Ron T.

2003-01-01

Engine fan diameter and Bypass Ratio (BPR) optimization studies have been conducted since the beginning of the turbofan age with the recognition that reducing the engine core jet velocity and increasing fan mass flow rate generally increases propulsive efficiency. However, performance tradeoffs limit the amount of fan flow achievable without reducing airplane efficiency. This study identifies the optimum engine fan diameter and BPR, given the advanced Ultra-Efficient Engine Technology (UEET) powerplant efficiencies, for use on an advanced subsonic airframe. Engine diameter studies have historically focused on specific engine size options, and were limited by existing technology and transportation infrastructure (e.g., ability to fit bare engines through aircraft doors and into cargo holds). This study is unique in defining the optimum fan diameter and drivers for future 2015 (UEET) powerplants while not limiting engine fan diameter by external constraints. This report follows on to a study identifying the system integration issues of UEET engines. This Engine Diameter study was managed by Boeing Phantom Works, Seattle, Washington through the NASA Glenn Revolutionary Aero Space Engine Research (RASER) contract under task order 10. Boeing Phantom Works, Huntington Beach, completed the engine/airplane sizing optimization, while the Boeing Commercial Airplane group (BCA) provided design oversight. A separate subcontract to support the overall project was issued to Tuskegee University.

Carnot cycle at finite power: attainability of maximal efficiency.

PubMed

Allahverdyan, Armen E; Hovhannisyan, Karen V; Melkikh, Alexey V; Gevorkian, Sasun G

2013-08-02

We want to understand whether and to what extent the maximal (Carnot) efficiency for heat engines can be reached at a finite power. To this end we generalize the Carnot cycle so that it is not restricted to slow processes. We show that for realistic (i.e., not purposefully designed) engine-bath interactions, the work-optimal engine performing the generalized cycle close to the maximal efficiency has a long cycle time and hence vanishing power. This aspect is shown to relate to the theory of computational complexity. A physical manifestation of the same effect is Levinthal's paradox in the protein folding problem. The resolution of this paradox for realistic proteins allows to construct engines that can extract at a finite power 40% of the maximally possible work reaching 90% of the maximal efficiency. For purposefully designed engine-bath interactions, the Carnot efficiency is achievable at a large power.

Working Characteristics of Variable Intake Valve in Compressed Air Engine

PubMed Central

Yu, Qihui; Shi, Yan; Cai, Maolin

2014-01-01

A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine. PMID:25379536

Working characteristics of variable intake valve in compressed air engine.

PubMed

Yu, Qihui; Shi, Yan; Cai, Maolin

2014-01-01

A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine.

Prospects for energy efficiency improvement and reduction of emissions and life cycle costs for natural gas vehicles

NASA Astrophysics Data System (ADS)

Kozlov, A. V.; Terenchenko, A. S.; Luksho, V. A.; Karpukhin, K. E.

2017-01-01

This work is devoted to the experimental investigation of the possibilities to reduce greenhouse gas emissions and to increase energy efficiency of engines that use natural gas as the main fuel and the analysis of economic efficiency of use of dual fuel engines in vehicles compared to conventional diesel. The results of experimental investigation of a 190 kW dual-fuel engine are presented; it is shown that quantitative and qualitative working process control may ensure thermal efficiency at the same level as that of the diesel engine and in certain conditions 5...8% higher. The prospects for reduction of greenhouse gas emissions have been assessed. The technical and economic evaluation of use of dual fuel engines in heavy-duty vehicles has been performed, taking into account the total life cycle. It is shown that it is possible to reduce life cycle costs by two times.

Specialized data analysis of SSME and advanced propulsion system vibration measurements

NASA Technical Reports Server (NTRS)

Coffin, Thomas; Swanson, Wayne L.; Jong, Yen-Yi

1993-01-01

The basic objectives of this contract were to perform detailed analysis and evaluation of dynamic data obtained during Space Shuttle Main Engine (SSME) test and flight operations, including analytical/statistical assessment of component dynamic performance, and to continue the development and implementation of analytical/statistical models to effectively define nominal component dynamic characteristics, detect anomalous behavior, and assess machinery operational conditions. This study was to provide timely assessment of engine component operational status, identify probable causes of malfunction, and define feasible engineering solutions. The work was performed under three broad tasks: (1) Analysis, Evaluation, and Documentation of SSME Dynamic Test Results; (2) Data Base and Analytical Model Development and Application; and (3) Development and Application of Vibration Signature Analysis Techniques.

Advanced Health Management System for the Space Shuttle Main Engine

NASA Technical Reports Server (NTRS)

Davidson, Matt; Stephens, John

2004-01-01

Boeing-Canoga Park (BCP) and NASA-Marshall Space Flight Center (NASA-MSFC) are developing an Advanced Health Management System (AHMS) for use on the Space Shuttle Main Engine (SSME) that will improve Shuttle safety by reducing the probability of catastrophic engine failures during the powered ascent phase of a Shuttle mission. This is a phased approach that consists of an upgrade to the current Space Shuttle Main Engine Controller (SSMEC) to add turbomachinery synchronous vibration protection and addition of a separate Health Management Computer (HMC) that will utilize advanced algorithms to detect and mitigate predefined engine anomalies. The purpose of the Shuttle AHMS is twofold; one is to increase the probability of successfully placing the Orbiter into the intended orbit, and the other is to increase the probability of being able to safely execute an abort of a Space Transportation System (STS) launch. Both objectives are achieved by increasing the useful work envelope of a Space Shuttle Main Engine after it has developed anomalous performance during launch and the ascent phase of the mission. This increase in work envelope will be the result of two new anomaly mitigation options, in addition to existing engine shutdown, that were previously unavailable. The added anomaly mitigation options include engine throttle-down and performance correction (adjustment of engine oxidizer to fuel ratio), as well as enhanced sensor disqualification capability. The HMC is intended to provide the computing power necessary to diagnose selected anomalous engine behaviors and for making recommendations to the engine controller for anomaly mitigation. Independent auditors have assessed the reduction in Shuttle ascent risk to be on the order of 40% with the combined system and a three times improvement in mission success.

Potential Uses of Occupational Analysis Data By Air Force Management Engineering Teams.

ERIC Educational Resources Information Center

McFarland, Barry P.

Both the occupational analysis program and the management engineering program are primarily concerned with task level descriptions of time spent to perform tasks required in the Air Force, the first being personnel specialty code oriented and the second being work center oriented. However two separate and independent techniques have been developed…

Role of interference in the photosynthetic heat engine

NASA Astrophysics Data System (ADS)

Xu, Y. Y.; Liu, J.

2014-11-01

The observation of quantum coherence in pigment-protein complexes has attracted considerable interest. One such endeavor entails applying a quantum heat engine to model the photosynthetic reaction center, but the definition of work used is inconsistent with that defined in quantum thermodynamics. Using the definition of work proposed in Weimer et al. [Europhys. Lett. 83, 30008 (2008), 10.1209/0295-5075/83/30008], we investigated two proposals for enhancing the performance of the photosynthetic reaction center. In proposal A, which is similar to that in Dorfman et al. [Proc. Natl. Acad. Sci. USA 110, 2746 (2013), 10.1073/pnas.1212666110], we found that the power and current-voltage characteristic of the heat engine can be increased by Fano interference but the efficiency cannot. In proposal B, which is similar to that in Creatore et al. [Phys. Rev. Lett. 111, 253601 (2013), 10.1103/PhysRevLett.111.253601], we found that the mechanism of strengthening the performance of the heat engine is invalid; i.e., the dipole-dipole interaction between two electron donors could not increase the power, efficiency, or current-voltage characteristic.

Baseline performance of the GPU 3 Stirling engine

NASA Technical Reports Server (NTRS)

Thieme, L. G.; Tew, R. C., Jr.

1978-01-01

A 10 horsepower single-cylinder rhombic-drive Stirling engine was converted to a research configuration to obtain data for validation of Stirling computer simulations. The engine was originally built by General Motors Research Laboratories for the U.S. Army in 1965 as part of a 3 kW engine-generator set, designated the GHU 3 (Ground Power Unit). This report presents test results for a range of heater gas temperatures, mean compression-space pressures, and engine speeds with both helium and hydrogen as the working fluids. Also shown are initial data comparisons with computer simulation predictions.

Review on Enhanced Heat Transfer Techniques using Modern Technologies for 4S Air Cooled Engines

NASA Astrophysics Data System (ADS)

Ramasubramanian, S.; Bupesh Raja, V. K.

2017-05-01

Engine performance is a biggest challenge and a vital area of concern when it comes to automobiles. Researchers across the globe have been working decades together meticulously improvising the performance of engine in terms of efficiency. The durability of the engine components mainly depends on the thermal stress it undergoes over the period of operation. Air cooling of engine is the simplest and most desirous technique that has been adopted for ages. In this regard fins or extended surfaces are employed for effective cooling of the cylinder while in operation. The conductive and convective heat transfer rate from the cylinder to the fins and in turn from the fins to surrounding ambience determines the effective performance of the engine. In this paper an attempt is made to review and summarize the various researches that were conducted on the Fins in terms of profile geometry, number of fins, size, thickness factor, material used etc., and to bring about a long term solution with the modern technologies like nano coatings and nano materials.

Session 6: Dynamic Modeling and Systems Analysis

NASA Technical Reports Server (NTRS)

Csank, Jeffrey; Chapman, Jeffryes; May, Ryan

2013-01-01

These presentations cover some of the ongoing work in dynamic modeling and dynamic systems analysis. The first presentation discusses dynamic systems analysis and how to integrate dynamic performance information into the systems analysis. The ability to evaluate the dynamic performance of an engine design may allow tradeoffs between the dynamic performance and operability of a design resulting in a more efficient engine design. The second presentation discusses the Toolbox for Modeling and Analysis of Thermodynamic Systems (T-MATS). T-MATS is a Simulation system with a library containing the basic building blocks that can be used to create dynamic Thermodynamic Systems. Some of the key features include Turbo machinery components, such as turbines, compressors, etc., and basic control system blocks. T-MAT is written in the Matlab-Simulink environment and is open source software. The third presentation focuses on getting additional performance from the engine by allowing the limit regulators only to be active when a limit is danger of being violated. Typical aircraft engine control architecture is based on MINMAX scheme, which is designed to keep engine operating within prescribed mechanical/operational safety limits. Using a conditionally active min-max limit regulator scheme, additional performance can be gained by disabling non-relevant limit regulators

Automotive Stirling engine systems development

NASA Technical Reports Server (NTRS)

Richey, A. E.

1984-01-01

The objective of the Automotive Stirling Engine (ASE) program is to develop a Stirling engine for automotive use that provides a 30 percent improvement in fuel economy relative to a comparable internal-combustion engine while meeting emissions goals. This paper traces the engine systems' development efforts focusing on: (1) a summary of engine system performance for all Mod I engines; (2) the development, program conducted for the upgraded Mod I; and (3) vehicle systems work conducted to enhance vehicle fuel economy. Problems encountered during the upgraded Mod I test program are discussed. The importance of the EPA driving cycle cold-start penalty and the measures taken to minimize that penalty with the Mod II are also addressed.

Cost Analysis of Maintenance Programs for Pre-Positioned War Reserve Material Stock (PWRMS)

DTIC Science & Technology

2002-06-01

perform electronic engine diagnosis and repair, complete engine and transmission rebuilding, powertrain and suspension work, bodywork , painting, and...cost is reimbursed by N44 • Any cost of breakdown maintenance such as transmission or engine failure. • Any cost of accident repair such as bodywork ...equipment in other TOA designators (TA10, P35, etc.) or any other maintenance such as corrective, breakdown, bodywork , or SLEP. Further studies need

Process Optimization Assessment: Fort Leonard Wood, MO and Fort Carson, CO

DTIC Science & Technology

2003-11-01

IUJ US Army Corps of Engineers, Engineer Research and Development Center Process Optimization Assessment Fort Leonard Wood, MO and Fort Carson, CO... Optimization Assessment: Fort Leonard Wood, MO and Fort Carson, CO Mike C.J. Lin and John Vavrin Construction Engineering Research Laboratory PO Box 9005...work performed a Process Optimization Assessment (POA) on behalf of Fort Leonard Wood, MO and Fort Carson, CO to identify process, energy, and

Towards an Automated Full-Turbofan Engine Numerical Simulation

NASA Technical Reports Server (NTRS)

Reed, John A.; Turner, Mark G.; Norris, Andrew; Veres, Joseph P.

2003-01-01

The objective of this study was to demonstrate the high-fidelity numerical simulation of a modern high-bypass turbofan engine. The simulation utilizes the Numerical Propulsion System Simulation (NPSS) thermodynamic cycle modeling system coupled to a high-fidelity full-engine model represented by a set of coupled three-dimensional computational fluid dynamic (CFD) component models. Boundary conditions from the balanced, steady-state cycle model are used to define component boundary conditions in the full-engine model. Operating characteristics of the three-dimensional component models are integrated into the cycle model via partial performance maps generated automatically from the CFD flow solutions using one-dimensional meanline turbomachinery programs. This paper reports on the progress made towards the full-engine simulation of the GE90-94B engine, highlighting the generation of the high-pressure compressor partial performance map. The ongoing work will provide a system to evaluate the steady and unsteady aerodynamic and mechanical interactions between engine components at design and off-design operating conditions.

Melt Infiltrated Ceramic Matrix Composites for Shrouds and Combustor Liners of Advanced Industrial Gas Turbines

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

Gregory Corman; Krishan Luthra; Jill Jonkowski

2011-01-07

This report covers work performed under the Advanced Materials for Advanced Industrial Gas Turbines (AMAIGT) program by GE Global Research and its collaborators from 2000 through 2010. A first stage shroud for a 7FA-class gas turbine engine utilizing HiPerComp{reg_sign}* ceramic matrix composite (CMC) material was developed. The design, fabrication, rig testing and engine testing of this shroud system are described. Through two field engine tests, the latter of which is still in progress at a Jacksonville Electric Authority generating station, the robustness of the CMC material and the shroud system in general were demonstrated, with shrouds having accumulated nearly 7,000more » hours of field engine testing at the conclusion of the program. During the latter test the engine performance benefits from utilizing CMC shrouds were verified. Similar development of a CMC combustor liner design for a 7FA-class engine is also described. The feasibility of using the HiPerComp{reg_sign} CMC material for combustor liner applications was demonstrated in a Solar Turbines Ceramic Stationary Gas Turbine (CSGT) engine test where the liner performed without incident for 12,822 hours. The deposition processes for applying environmental barrier coatings to the CMC components were also developed, and the performance of the coatings in the rig and engine tests is described.« less

System for Anomaly and Failure Detection (SAFD) system development

NASA Technical Reports Server (NTRS)

Oreilly, D.

1992-01-01

This task specified developing the hardware and software necessary to implement the System for Anomaly and Failure Detection (SAFD) algorithm, developed under Technology Test Bed (TTB) Task 21, on the TTB engine stand. This effort involved building two units; one unit to be installed in the Block II Space Shuttle Main Engine (SSME) Hardware Simulation Lab (HSL) at Marshall Space Flight Center (MSFC), and one unit to be installed at the TTB engine stand. Rocketdyne personnel from the HSL performed the task. The SAFD algorithm was developed as an improvement over the current redline system used in the Space Shuttle Main Engine Controller (SSMEC). Simulation tests and execution against previous hot fire tests demonstrated that the SAFD algorithm can detect engine failure as much as tens of seconds before the redline system recognized the failure. Although the current algorithm only operates during steady state conditions (engine not throttling), work is underway to expand the algorithm to work during transient condition.

Thermoelectric energy converters under a trade-off figure of merit with broken time-reversal symmetry

NASA Astrophysics Data System (ADS)

Iyyappan, I.; Ponmurugan, M.

2017-09-01

We study the performance of a three-terminal thermoelectric device such as heat engine and refrigerator with broken time-reversal symmetry by applying the unified trade-off figure of merit (\\dotΩ criterion) which accounts for both useful energy and losses. For the heat engine, we find that a thermoelectric device working under the maximum \\dotΩ criterion gives a significantly better performance than a device working at maximum power output. Within the framework of linear irreversible thermodynamics such a direct comparison is not possible for refrigerators, however, our study indicates that, for refrigerator, the maximum cooling load gives a better performance than the maximum \\dotΩ criterion for a larger asymmetry. Our results can be useful to choose a suitable optimization criterion for operating a real thermoelectric device with broken time-reversal symmetry.

Vehicle Engineering Development Activities at the Marshall Space Flight Center

NASA Technical Reports Server (NTRS)

Fisher, Mark F.; Champion, Robert H., Jr.

1999-01-01

New initiatives in the Space Transportation Directorate at the Marshall Space Flight Center include an emphasis on Vehicle Engineering to enhance the strong commitment to the Directorate's projects in the development of flight hardware and flight demonstrators for the advancement of space transportation technology. This emphasis can be seen in the activities of a newly formed organization in the Transportation Directorate, The Vehicle Subsystems Engineering Group. The functions and type of activities that this group works on are described. The current projects of this group are outlined including a brief description of the status and type of work that the group is performing. A summary section is included to describe future activities.

Cognitive engineering and health informatics: Applications and intersections.

PubMed

Hettinger, A Zachary; Roth, Emilie M; Bisantz, Ann M

2017-03-01

Cognitive engineering is an applied field with roots in both cognitive science and engineering that has been used to support design of information displays, decision support, human-automation interaction, and training in numerous high risk domains ranging from nuclear power plant control to transportation and defense systems. Cognitive engineering provides a set of structured, analytic methods for data collection and analysis that intersect with and complement methods of Cognitive Informatics. These methods support discovery of aspects of the work that make performance challenging, as well as the knowledge, skills, and strategies that experts use to meet those challenges. Importantly, cognitive engineering methods provide novel representations that highlight the inherent complexities of the work domain and traceable links between the results of cognitive analyses and actionable design requirements. This article provides an overview of relevant cognitive engineering methods, and illustrates how they have been applied to the design of health information technology (HIT) systems. Additionally, although cognitive engineering methods have been applied in the design of user-centered informatics systems, methods drawn from informatics are not typically incorporated into a cognitive engineering analysis. This article presents a discussion regarding ways in which data-rich methods can inform cognitive engineering. Copyright © 2017 Elsevier Inc. All rights reserved.

Numerical Prediction of the Influence of Thrust Reverser on Aeroengine's Aerodynamic Stability

NASA Astrophysics Data System (ADS)

Zhiqiang, Wang; Xigang, Shen; Jun, Hu; Xiang, Gao; Liping, Liu

2017-11-01

A numerical method was developed to predict the aerodynamic stability of a high bypass ratio turbofan engine, at the landing stage of a large transport aircraft, when the thrust reverser was deployed. 3D CFD simulation and 2D aeroengine aerodynamic stability analysis code were performed in this work, the former is to achieve distortion coefficient for the analysis of engine stability. The 3D CFD simulation was divided into two steps, the single engine calculation and the integrated aircraft and engine calculation. Results of the CFD simulation show that with the decreasing of relative wind Mach number, the engine inlet will suffer more severe flow distortion. The total pressure and total temperature distortion coefficients at the inlet of the engines were obtained from the results of the numerical simulation. Then an aeroengine aerodynamic stability analysis program was used to quantitatively analyze the aerodynamic stability of the high bypass ratio turbofan engine. The results of the stability analysis show that the engine can work stably, when the reverser flow is re-ingested. But the anti-distortion ability of the booster is weaker than that of the fan and high pressure compressor. It is a weak link of engine stability.

A Self-Circulating Heat Exchanger for Use in Stirling and Thermoacoustic-Stirling Engines

NASA Astrophysics Data System (ADS)

Backhaus, Scott; Reid, Robert S.

2005-02-01

A major technical hurdle to the implementation of large Stirling engines or thermoacoustic engines is the reliability, performance, and manufacturability of the hot heat exchanger that brings high-temperature heat into the engine. Unlike power conversion devices that utilize steady flow, the oscillatory nature of the flow in Stirling and thermoacoustic engines restricts the length of a traditional hot heat exchanger to a peak-to-peak gas displacement, which is usually around 0.2 meters or less. To overcome this restriction, a new hot heat exchanger has been devised that uses a fluid diode in a looped pipe, which is resonantly driven by the oscillating gas pressure in the engine itself, to circulate the engine's working fluid around the loop. Instead of thousands of short, intricately interwoven passages that must be individually sealed, this new design consists of a few pipes that are typically 10 meters long. This revolutionary approach eliminates thousands of hermetic joints, pumps the engine's working fluid to and from a remote heat source without using moving parts, and does so without compromising on heat transfer surface area. Test data on a prototype loop integrated with a 1-kW thermoacoustic engine will be presented.

Engineering performance metrics

NASA Astrophysics Data System (ADS)

Delozier, R.; Snyder, N.

1993-03-01

Implementation of a Total Quality Management (TQM) approach to engineering work required the development of a system of metrics which would serve as a meaningful management tool for evaluating effectiveness in accomplishing project objectives and in achieving improved customer satisfaction. A team effort was chartered with the goal of developing a system of engineering performance metrics which would measure customer satisfaction, quality, cost effectiveness, and timeliness. The approach to developing this system involved normal systems design phases including, conceptual design, detailed design, implementation, and integration. The lessons teamed from this effort will be explored in this paper. These lessons learned may provide a starting point for other large engineering organizations seeking to institute a performance measurement system accomplishing project objectives and in achieving improved customer satisfaction. To facilitate this effort, a team was chartered to assist in the development of the metrics system. This team, consisting of customers and Engineering staff members, was utilized to ensure that the needs and views of the customers were considered in the development of performance measurements. The development of a system of metrics is no different than the development of any type of system. It includes the steps of defining performance measurement requirements, measurement process conceptual design, performance measurement and reporting system detailed design, and system implementation and integration.

Addressing Uncertainty in Signal Propagation and Sensor Performance Predictions

DTIC Science & Technology

2008-11-01

Army Engineer Research and Develop- ment Center (ERDC) AT42 work package Environmental Awareness for Sensor Employment (EASE). M. S. Lewis is an Oak...L. Pettit, Sean Mackay, Matthew S. Lewis , and Peter M. Seman November 2008 C ol d R eg io n s R es ea rc h an d E n gi n ee ri n g La b...Propagation and Sensor Performance Predictions D. Keith Wilson, Matthew S. Lewis , and Peter M. Seman Cold Regions Research and Engineering Laboratory

A Correlation Between Quality Management Metrics and Technical Performance Measurement

DTIC Science & Technology

2007-03-01

Engineering Working Group SME Subject Matter Expert SoS System of Systems SPI Schedule performance Index SSEI System of Systems Engineering and...and stated as such [Q, M , M &G]. The QMM equation is given by: 12 QMM=0.92RQM+0.67EPM+0.55RKM+1.86PM, where: RGM is the requirements management...schedule. Now if corrective action is not taken, the project/task will be completed behind schedule and over budget. m . As well as the derived

Cold-air performance of the compressor-drive turbine of the Department of Energy baseline automobile gas-turbine engine

NASA Technical Reports Server (NTRS)

Roelke, R. J.; Mclallin, K. L.

1978-01-01

The aerodynamic performance of the compressor-drive turbine of the DOE baseline gas-turbine engine was determined over a range of pressure ratios and speeds. In addition, static pressures were measured in the diffusing transition duct located immediately downstream of the turbine. Results are presented in terms of mass flow, torque, specific work, and efficiency for the turbine and in terms of pressure recovery and effectiveness for the transition duct.

Thermodynamic Analysis of Dual-Mode Scramjet Engine Operation and Performance

NASA Technical Reports Server (NTRS)

Riggins, David; Tacket, Regan; Taylor, Trent; Auslender, Aaron

2006-01-01

Recent analytical advances in understanding the performance continuum (the thermodynamic spectrum) for air-breathing engines based on fundamental second-law considerations have clarified scramjet and ramjet operation, performance, and characteristics. Second-law based analysis is extended specifically in this work to clarify and describe the performance characteristics for dual-mode scramjet operation in the mid-speed range of flight Mach 4 to 7. This is done by a fundamental investigation of the complex but predictable interplay between heat release and irreversibilities in such an engine; results demonstrate the flow and performance character of the dual mode regime and of dual mode transition behavior. Both analytical and computational (multi-dimensional CFD) studies of sample dual-mode flow-fields are performed in order to demonstrate the second-law capability and performance and operability issues. The impact of the dual-mode regime is found to be characterized by decreasing overall irreversibility with increasing heat release, within the operability limits of the system.

Comparison of Cross Flow Filtration Performance for Manganese Oxide/Sludge Mixtures and Monosodium Titanate/Sludge Mixtures

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

Poirier, M.R.

2002-06-07

Personnel performed engineering-scale tests at the Filtration Research Engineering Demonstration (FRED) to determine crossflow filter performance with a 5.6 M sodium solution containing varying concentrations of sludge and sodium permanganate. The work represents another in a series of collaborative efforts between the University of South Carolina and the Savannah River Technology Center in support of the process development efforts for the Savannah River Site. The current tests investigated filter performance with slurry containing simulated Tank 40H Sludge and sodium permanganate at concentrations between 0.070 weight percent and 3.04 weight percent insoluble solids.

Hydraulic dynamic analysis

NASA Technical Reports Server (NTRS)

Gale, R. L.; Nease, A. W.; Nelson, D. J.

1978-01-01

Computer program mathematically describes complete hydraulic systems to study their dynamic performance. Program employs subroutines that simulate components of hydraulic system, which are then controlled by main program. Program is useful to engineers working with detailed performance results of aircraft, spacecraft, or similar hydraulic systems.

Optimization of suitable ethanol blend ratio for motorcycle engine using response surface method.

PubMed

Chen, Yu-Liang; Chen, Suming; Tsai, Jin-Ming; Tsai, Chao-Yin; Fang, Hsin-Hsiung; Yang, I-Chang; Liu, Sen-Yuan

2012-01-01

In view of energy shortage and air pollution, ethanol-gasoline blended fuel used for motorcycle engine was studied in this work. The emissions of carbon monoxide (CO), nitrogen oxides (NO(X)) and engine performance of a 125 cc four-stroke motorcycle engine with original carburetor using ethanol-gasoline fuels were investigated. The model of three-variable Box Behnken design (BBD) was used for experimental design, the ethanol blend ratios were prepared at 0, 10, 20 vol%; the speeds of motorcycle were selected as 30, 45, 60 km/h; and the throttle positions were set at 30, 60, 90 %. Both engine performance and air pollutant emissions were then analyzed by response surface method (RSM) to yield optimum operation parameters for tolerable pollutant emissions and maximum engine performance. The RSM optimization analysis indicated that the most suitable ethanol-gasoline blended ratio was found at the range of 3.92-4.12 vol% to yield a comparable fuel conversion efficiency, while considerable reductions of exhaust pollutant emissions of CO (-29 %) and NO(X) (-12 %) when compared to pure gasoline fuel. This study demonstrated low ethanol-gasoline blended fuels could be used in motorcycle carburetor engines without any modification to keep engine power while reducing exhaust pollutants.

RE-1000 free-piston Stirling engine hydraulic output system description

NASA Technical Reports Server (NTRS)

Schreiber, Jeffrey G.; Geng, Steven M.

1987-01-01

The NASA Lewis Research Center was involved in free-piston Stirling engine research since 1976. Most of the work performed in-house was related to characterization of the RE-1000 engine. The data collected from the RE-1000 tests were intended to provide a data base for the validation of Stirling cycle simulations. The RE-1000 was originally build with a dashpot load system which did not convert the output of the engine into useful power, but was merely used as a load for the engine to work against during testing. As part of the interagency program between NASA Lewis and the Oak Ridge National Laboratory, (ORNL), the RE-1000 was converted into a configuration that produces useable hydraulic power. A goal of the hydraulic output conversion effort was to retain the same thermodynamic cycle that existed with the dashpot loaded engine. It was required that the design must provide a hermetic seal between the hydraulic fluid and the working gas of the engine. The design was completed and the hardware was fabricated. The RE-1000 was modified in 1985 to the hydraulic output configuration. The early part of the RE-1000 hydraulic output program consisted of modifying hardware and software to allow the engine to run at steady-state conditions. A complete description of the engine is presented in sufficient detail so that the device can be simulated on a computer. Tables are presented showing the masses of the oscillating components and key dimensions needed for modeling purposes. Graphs are used to indicate the spring rate of the diaphragms used to separate the helium of the working and bounce space from the hydraulic fluid.

Laboratory and Pilot Scale Evaluation of Coagulation, Clarification, and Filtration for Upgrading Sewage Lagoon Effluents.

DTIC Science & Technology

1980-08-01

AD-AGAB 906 ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG--ETC FIG 14/2 LABORATORY AND PILOT SCALE EVALUATION OF COAGULATION, CLARIFICA -ETC U...FILTRATION FOR LWGRADING JEWAGE LAGOON EFFLUENTS~ w IL j0 ( M John ullinane, Jr., Richard A. hafer (0 Environmental Laboratory gel U. S. Army Engineer ...Shafer 9. PERFORMING ORGANIZATION NAME AND ADORESS SO. PROGRAM ELEMENT, PROJECT, TASK AREA a WORK UNIT NUMBERS U. S. Army Engineer Waterways Experiment

Diesel Cylinder Gas-Side Heat Flux to a Ceramic Surface

DTIC Science & Technology

1986-06-01

developed a flameless method of lean premixed combustion which would provide a much better test medium. If the wall jet instrument is to ever work, it will...collected by use of the flameless - combustion -engine or by use of methanol in a diesel engine. Neither of these options were available during the contract...Borman DAAG29-81-K-0082 Jeffrey C. Huang 9. PERFORMING ORGANIZATION NAME AND ADORESS 10. PROGRAM ELEMENT, PROJECT, TASK Engine Combustion Laboratory

48 CFR 9.502 - Applicability.

Code of Federal Regulations, 2014 CFR

2014-10-01

... subpart applies to contracts with either profit or nonprofit organizations, including nonprofit... engineering and technical direction work performed by a contractor that does not have overall contractual...

Similarities and Differences in the Academic Education of Software Engineering and Architectural Design Professionals

ERIC Educational Resources Information Center

Hazzan, Orit; Karni, Eyal

2006-01-01

This article focuses on the similarities and differences in the academic education of software engineers and architects. The rationale for this work stems from our observation, each from the perspective of her or his own discipline, that these two professional design and development processes share some similarities. A pilot study was performed,…

Hypersonic propulsion. [scramjet technology

NASA Technical Reports Server (NTRS)

Anderson, G. Y.

1975-01-01

The NASA research on scramjet technology for speeds above Mach 5 is reported. A brief overview of the NASA Hypersonic Research Engine (HRE) project is presented with emphasis on the most significant contributions on the HRE to scramjet technology. The work on high-performance airframe-integrated scramjet engines is described, and a new versatile research airplane is discussed with emphasis on propulsion.

RADC thermal guide for reliability engineers

NASA Astrophysics Data System (ADS)

Morrison, G. N.; Kallis, J. M.; Strattan, L. A.; Jones, I. R.; Lena, A. L.

1982-06-01

This guide was developed to provide a reliability engineer, who is not proficient in thermal design and analysis techniques, with the tools for managing and evaluating the thermal design and production of electronic equipment. It defines the requirements and tasks that should be addressed in system equipment specifications and statements of work, and describes how to evaluate performance.

Release Fixed Heel Point (FHP) Accommodation Model Verification and Validation (V and V) Plan - Rev A

DTIC Science & Technology

2017-01-23

5e. TASK NUMBER N/A 5f. WORK UNIT NUMBER N/A 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) AND ADDRESS(ES) RDECOM-TARDEC-ACT Attn...occupant work space, central 90% of the Soldier population, encumbrance, posture and position, verification and validation, computer aided design...factors engineers could benefit by working with vehicle designers to perform virtual assessments in CAD when there is not enough time and/or funding to

Failure Engineering Study and Accelerated Stress Test Results for the Mars Global Surveyor Spacecraft's Power Shunt Assemblies

NASA Technical Reports Server (NTRS)

Gibbel, Mark; Larson, Timothy

2000-01-01

An Engineering-of-Failure approach to designing and executing an accelerated product qualification test was performed to support a risk assessment of a "work-around" necessitated by an on-orbit failure of another piece of hardware on the Mars Global Surveyor spacecraft. The proposed work-around involved exceeding the previous qualification experience both in terms of extreme cold exposure level and in terms of demonstrated low cycle fatigue life for the power shunt assemblies. An analysis was performed to identify potential failure sites, modes and associated failure mechanisms consistent with the new use conditions. A test was then designed and executed which accelerated the failure mechanisms identified by analysis. Verification of the resulting failure mechanism concluded the effort.

Recombination Catalysts for Hypersonic Fuels

NASA Technical Reports Server (NTRS)

Chinitz, W.

1998-01-01

The goal of commercially-viable access to space will require technologies that reduce propulsion system weight and complexity, while extracting maximum energy from the products of combustion. This work is directed toward developing effective nozzle recombination catalysts for the supersonic and hypersonic aeropropulsion engines used to provide such access to space. Effective nozzle recombination will significantly reduce rk=le length (hence, propulsion system weight) and reduce fuel requirements, further decreasing the vehicle's gross lift-off weight. Two such catalysts have been identified in this work, barium and antimony compounds, by developing chemical kinetic reaction mechanisms for these materials and determining the engine performance enhancement for a typical flight trajectory. Significant performance improvements are indicated, using only 2% (mole or mass) of these compounds in the combustor product gas.

Performance and emission characteristics of a low heat rejection engine with different air gap thicknesses with Jatropha oil based bio-diesel.

PubMed

Murali Krishna, M V S; Sarita, G; Seshagiri Rao, V V R; Chowdary, R P; Ramana Reddy, Ch V

2010-04-01

The research work on alternate fuels has been the topic of wider interest in the context of depletion of fossil fuels and increasing of pollution levels of the engines with conventional fossil fuels. Alcohols and vegetable oils are considered to replace diesel fuels as they are renewable in nature. However, use of alcohols in internal combustion engines is limited in India, as these fuels are diverted to PetroChemical industries and hence much emphasis is given to the non-edible vegetable oils as alternate fuels in internal combustion engines. However, the drawbacks of low volatility and high viscosity associated with non-edible vegetable oils call for hot combustion chamber, provided by low heat rejection (LHR) diesel engine. Investigations are carried out on a LHR diesel engine with varied air gap thicknesses and injection pressures with jatropha oil based bio-diesel at normal temperature. Performance is improved with high degree of insulation with LHR engine with vegetable oil in comparison with conventional engine (CE) with pure diesel operation.

Predictors of effective leadership in industry - should engineering education focus on traditional intelligence, personality, or emotional intelligence?

NASA Astrophysics Data System (ADS)

Lappalainen, Pia

2015-03-01

Despite the changing global and industrial conditions requiring new approaches to leadership, management training as part of higher engineering education still remains understudied. The subsequent gap in engineering education calls for research on today's leader requirements and pedagogy supporting the inclusion of management competence in higher engineering education. Previous organisation and management studies have, on a general level, established the importance of managerial qualities for industrial performance, but the nature and make-up of these qualifications has not been adequately analysed. To fill the related research gap, the present work embarked on a quantitative empirical effort to identify predictors of successful leadership in engineering. In particular, this study investigated relationships between perceived leader performance and three dimensions of managerial capability: (1) mathematical-logical intelligence, (2) personality, and (3) socio-emotional intelligence. This work complemented previous research by resorting to both self-reports and other-reports: the results acquired from the managerial sample were compared to subordinate perceptions as measured through an emotive intelligence other-report and a general managerial competence multi-source appraisal. The sample comprised 80 superiors and 354 subordinates operating in seven organisations in engineering industries. The results from the quantitative measurements signalled the strongest correlation for socio-emotional intelligence and certain personality dimensions with successful leadership. Mathematical-logical intelligence demonstrated no correlation with subordinate perceptions of good leadership. These findings lay the foundation for the incorporation of socio-emotive skills into higher engineering education.

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.

An overview of NASA intermittent combustion engine research

NASA Technical Reports Server (NTRS)

Willis, E. A.; Wintucky, W. T.

1984-01-01

This paper overviews the current program, whose objective is to establish the generic technology base for advanced aircraft I.C. engines of the early 1990's and beyond. The major emphasis of this paper is on development of the past two years. Past studies and ongoing confirmatory experimental efforts are reviewed, which show unexpectedly high potential when modern aerospace technologies are applied to inherently compact and balanced I.C. engine configurations. Currently, the program is focussed on two engine concepts, the stratified-charge, multi-fuel rotary and the lightweight two-stroke diesel. A review is given of contracted and planned high performance one-rotor and one-cylinder test engine work addressing several levels of technology. Also reviewed are basic supporting efforts, e.g., the development and experimental validation of computerized airflow and combustion process models, being performed in-house at Lewis Research Center and by university grants. Previously announced in STAR as N84-24583

Nozzle Numerical Analysis Of The Scimitar Engine

NASA Astrophysics Data System (ADS)

Battista, F.; Marini, M.; Cutrone, L.

2011-05-01

This work describes part of the activities on the LAPCAT-II A2 vehicle, in which starting from the available conceptual vehicle design and the related pre- cooled turbo-ramjet engine called SCIMITAR, well- thought assumptions made for performance figures of different components during the iteration process within LAPCAT-I will be assessed in more detail. In this paper it is presented a numerical analysis aimed at the design optimization of the nozzle contour of the LAPCAT A2 SCIMITAR engine designed by Reaction Engines Ltd. (REL) (see Figure 1). In particular, nozzle shape optimization process is presented for cruise conditions. All the computations have been carried out by using the CIRA C3NS code in non equilibrium conditions. The effect of considering detailed or reduced chemical kinetic schemes has been analyzed with a particular focus on the production of pollutants. An analysis of engine performance parameters, such as thrust and combustion efficiency has been carried out.

An overview of NASA intermittent combustion engine research

NASA Technical Reports Server (NTRS)

Willis, E. A.; Wintucky, W. T.

1984-01-01

This paper overviews the current program, whose objective is to establish the generic technology base for advanced aircraft I.C. engines of the early 1990's and beyond. The major emphasis of this paper is on development of the past two years. Past studies and ongoing confirmatory experimental efforts are reviewed, which show unexpectly high potential when modern aerospace technologies are applied to inherently compact and balanced I.C. engine configurations. Currently, the program is focussed on two engine concepts the stratified-charge, multi-fuel rotary, and the lightweight two-stroke diesel. A review is given of contracted and planned high performance one-rotor and one-cylinder test engine work addressing several levels of technology. Also reviewed are basic supporting efforts, e.g., the development and experimental validation of computerized airflow and combustion process models, being performed in-house at Lewis Research Center and by university grants.

Aviation Engine Test Facilities (AETF) fire protection study

NASA Astrophysics Data System (ADS)

Beller, R. C.; Burns, R. E.; Leonard, J. T.

1989-07-01

An analysis is presented to the effectiveness of various types of fire fighting agents in extinguishing the kinds of fires anticipated in Aviation Engine Test Facilities (AETF), otherwise known as Hush Houses. The agents considered include Aqueous Film-Forming Foam, Halon 1301, Halon 1211 and water. Previous test work has shown the rapidity with which aircraft, especially high performance aircraft, can be damaged by fire. Based on this, tentative criteria for this evaluation included a maximum time of 20 s from fire detection to extinguishment and a period of 30 min in which the agent would prevent reignition. Other issues examined included: toxicity, corrosivity, ease of personnel egress, system reliability, and cost effectiveness. The agents were evaluated for their performance in several fire scenarios, including: under frame fire, major engine fire, engine disintegration fire, high-volume pool fire with simultaneous spill fire, internal electrical fire, and runaway engine fire.

2nd Generation RLV Risk Reduction Definition Program: Pratt & Whitney Propulsion Risk Reduction Requirements Program (TA-3 & TA-4)

NASA Technical Reports Server (NTRS)

Matlock, Steve

2001-01-01

This is the final report and addresses all of the work performed on this program. Specifically, it covers vehicle architecture background, definition of six baseline engine cycles, reliability baseline (space shuttle main engine QRAS), and component level reliability/performance/cost for the six baseline cycles, and selection of 3 cycles for further study. This report further addresses technology improvement selection and component level reliability/performance/cost for the three cycles selected for further study, as well as risk reduction plans, and recommendation for future studies.

Long-term effects of the transient COD concentration on the performance of microbial fuel cells.

PubMed

Mateo, S; Gonzalez Del Campo, A; Lobato, J; Rodrigo, M; Cañizares, P; Fernandez-Morales, F J

2016-07-08

In this work, the long-term effects of transient chemical oxygen demands (COD) concentrations over the performance of a microbial fuel cell were studied. From the obtained results, it was observed that the repetitive change in the COD loading rate during 12 h conditioned the behavior of the system during periods of up to 7 days. The main modifications were the enhancement of the COD consumption rate and the exerted current. These enhancements yielded increasing Coulombic efficiencies (CEs) when working with COD concentrations of 300 mg/L, but constant CEs when working with COD concentrations from 900 to 1800 mg/L. This effect could be explained by the higher affinity for the substrate of Geobacter than that of the nonelectrogenic organisms such as Clostridia. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:883-890, 2016. © 2016 American Institute of Chemical Engineers.

Two coupled, driven Ising spin systems working as an engine.

PubMed

Basu, Debarshi; Nandi, Joydip; Jayannavar, A M; Marathe, Rahul

2017-05-01

Miniaturized heat engines constitute a fascinating field of current research. Many theoretical and experimental studies are being conducted that involve colloidal particles in harmonic traps as well as bacterial baths acting like thermal baths. These systems are micron-sized and are subjected to large thermal fluctuations. Hence, for these systems average thermodynamic quantities, such as work done, heat exchanged, and efficiency, lose meaning unless otherwise supported by their full probability distributions. Earlier studies on microengines are concerned with applying Carnot or Stirling engine protocols to miniaturized systems, where system undergoes typical two isothermal and two adiabatic changes. Unlike these models we study a prototype system of two classical Ising spins driven by time-dependent, phase-different, external magnetic fields. These spins are simultaneously in contact with two heat reservoirs at different temperatures for the full duration of the driving protocol. Performance of the model as an engine or a refrigerator depends only on a single parameter, namely the phase between two external drivings. We study this system in terms of fluctuations in efficiency and coefficient of performance (COP). We find full distributions of these quantities numerically and study the tails of these distributions. We also study reliability of the engine. We find the fluctuations dominate mean values of efficiency and COP, and their probability distributions are broad with power law tails.

Two coupled, driven Ising spin systems working as an engine

NASA Astrophysics Data System (ADS)

Basu, Debarshi; Nandi, Joydip; Jayannavar, A. M.; Marathe, Rahul

2017-05-01

Miniaturized heat engines constitute a fascinating field of current research. Many theoretical and experimental studies are being conducted that involve colloidal particles in harmonic traps as well as bacterial baths acting like thermal baths. These systems are micron-sized and are subjected to large thermal fluctuations. Hence, for these systems average thermodynamic quantities, such as work done, heat exchanged, and efficiency, lose meaning unless otherwise supported by their full probability distributions. Earlier studies on microengines are concerned with applying Carnot or Stirling engine protocols to miniaturized systems, where system undergoes typical two isothermal and two adiabatic changes. Unlike these models we study a prototype system of two classical Ising spins driven by time-dependent, phase-different, external magnetic fields. These spins are simultaneously in contact with two heat reservoirs at different temperatures for the full duration of the driving protocol. Performance of the model as an engine or a refrigerator depends only on a single parameter, namely the phase between two external drivings. We study this system in terms of fluctuations in efficiency and coefficient of performance (COP). We find full distributions of these quantities numerically and study the tails of these distributions. We also study reliability of the engine. We find the fluctuations dominate mean values of efficiency and COP, and their probability distributions are broad with power law tails.

Computational Investigation on the performance of thermo-acoustically driven pulse tube refrigerator

NASA Astrophysics Data System (ADS)

Skaria, Mathew; Rasheed, K. K. Abdul; Shafi, K. A.; Kasthurirengan, S.; Behera, Upendra

2017-02-01

A Thermoacoustic Pulse Tube Refrigeration (TAPTR) system employs a thermo acoustic engine as the pressure wave generator instead of mechanical compressor. Such refrigeration systems are highly reliable due to the absence of moving components, structural simplicity and the use of environmental friendly working fluids. In the present work, a traveling wave thermoacoustic primmover (TWTAPM) has been developed and it is coupled to a pulse tube cryocooler. The performance of TAPTR depends on the operating and working fluid parameters. Simulation studies of the system has been performed using ANSYS Fluent and compared with experimental results.

Composite Structures Materials Testing for the Orion Crew Vehicle Heat Shield

NASA Technical Reports Server (NTRS)

Khemani, Farah N.

2011-01-01

As research is being performed for the new heat shield for the Orion capsule, National Aeronautics and Space Administration (NASA) is developing the first composite heat shield. As an intern of the Structures Branch in the Engineering Directorate (ES 2), my main task was to set up a test plan to determine the material properties of the honeycomb that will be used on the Orion Crew Module heat shield to verify that the composite is suitable for the capsule. Before conducting composite shell tests, which are performed to simulate the crush performance of the heat shield on the capsule, it is necessary to determine the compression and shear properties of the composite used on the shell. During this internship, I was responsible for developing a test plan, designing parts for the test fixtures as well as getting them fabricated for the honeycomb shear and compression testing. This involved work in Pro/Engineer as well as coordinating with Fab Express, the Building 9 Composite Shop and the Structures Test Laboratory (STL). The research and work executed for this project will be used for composite sandwich panel testing in the future as well. As a part of the Structures Branch, my main focus was to research composite structures. This involves system engineering and integration (SE&I) integration, manufacturing, and preliminary testing. The procedures for these projects that were executed during this internship included design work, conducting tests and performing analysis.

Measuring the Effect of an Online Learning Community on Engineering Cooperative Education Students' Perceived and Measured Learning

ERIC Educational Resources Information Center

Todd, Anita M.

2013-01-01

This quasi-experimental, static-group comparison study of two non-equivalent groups examined how Work-Integrated Learning (WIL) community participation of at-work, cooperative education students affected student perceived performance, perceived learning, and measured learning with student grade point average (GPA) and work term as covariates. The…

Scholte wave generation during single tracking location shear wave elasticity imaging of engineered tissues.

PubMed

Mercado, Karla P; Langdon, Jonathan; Helguera, María; McAleavey, Stephen A; Hocking, Denise C; Dalecki, Diane

2015-08-01

The physical environment of engineered tissues can influence cellular functions that are important for tissue regeneration. Thus, there is a critical need for noninvasive technologies capable of monitoring mechanical properties of engineered tissues during fabrication and development. This work investigates the feasibility of using single tracking location shear wave elasticity imaging (STL-SWEI) for quantifying the shear moduli of tissue-mimicking phantoms and engineered tissues in tissue engineering environments. Scholte surface waves were observed when STL-SWEI was performed through a fluid standoff, and confounded shear moduli estimates leading to an underestimation of moduli in regions near the fluid-tissue interface.

Impact of oxygenated additives to diesel-biodiesel blends in the context of performance and emissions characteristics of a CI engine

NASA Astrophysics Data System (ADS)

Mahmudul, H. M.; Hagos, Ftwi Y.; Mamat, Rizalman; Abdullah, Abdul A.

2016-11-01

Butanol is receiving huge interest in the area of alternative fuel in the compression ignition (CI) engines. In this work, butanol is used as an oxygenated additive to diesel and biodiesel blend fuels to evaluate the performance and emission of CI engine. The commercially available pure diesel fuel (D100) and 80% commercially available diesel- biodiesel bled (5% biodiesel and 95% by volume) and 20% butanol (BU20) fuels were investigated to evaluate the effects of the fuel blends on the performance and exhaust emissions of a single cylinder diesel engine. The experiment was conducted at fixed load of 75% with the five engine speeds (from 1200-2400 rpm with an interval of 300 rpm). The engine performance parameters such as power, torque, fuel consumption and thermal efficiency and exhaust gas emissions such as nitrogen oxides, carbon monoxide, and exhaust gas temperature were analysed from the experimental data. The results shows that although butanol addition has caused a slight reduction in power and torque values (11.1% and 3.5%, respectively), the emission values of the engine were improved. With respect to the exhaust gas temperature, CO and NOx emissions, of BU20 is reported to have reduction by 17.7%, 20% and 3%, respectively than the B100. Therefore, butanol can be used as a fuel additive to diesel-biodiesel blends.

High temperature dynamic engine seal technology development

NASA Technical Reports Server (NTRS)

Steinetz, Bruce M.; Dellacorte, Christopher; Machinchick, Michael; Mutharasan, Rajakkannu; Du, Guang-Wu; Ko, Frank; Sirocky, Paul J.; Miller, Jeffrey H.

1992-01-01

Combined cycle ramjet/scramjet engines being designed for advanced hypersonic vehicles, including the National Aerospace Plane (NASP), require innovative high temperature dynamic seals to seal the sliding interfaces of the articulated engine panels. New seals are required that will operate hot (1200 to 2000 F), seal pressures ranging from 0 to 100 psi, remain flexible to accommodate significant sidewall distortions, and resist abrasion over the engine's operational life. This report reviews the recent high temperature durability screening assessments of a new braided rope seal concept, braided of emerging high temperature materials, that shows promise of meeting many of the seal demands of hypersonic engines. The paper presents durability data for: (1) the fundamental seal building blocks, a range of candidate ceramic fiber tows; and for (2) braided rope seal subelements scrubbed under engine simulated sliding, temperature, and preload conditions. Seal material/architecture attributes and limitations are identified through the investigations performed. The paper summarizes the current seal technology development status and presents areas in which future work will be performed.

Final Environmental Impact Statement Permit Application by United States Steel Corp. Proposed Lake Front Steel Mill, Conneaut, Ohio. Volume 1,

DTIC Science & Technology

1979-04-01

FRONT STEEL MILL CONNEAUT, OHIO 6. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(a) S. CONTRACT OR GRANT NUMBERS) Paul G. Leuchner and Gregory P. Keppel... PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT. PROJECT, TASK AREA & WORK UNIT NUMBERS U.S. Army Engineer District, Buffalo 1776 Niagara...the Army permit to perform certain work in Lake Erie and its tributaries. Activities proposed by the applicant include the construction of a water

Applying chemical engineering concepts to non-thermal plasma reactors

NASA Astrophysics Data System (ADS)

Pedro AFFONSO, NOBREGA; Alain, GAUNAND; Vandad, ROHANI; François, CAUNEAU; Laurent, FULCHERI

2018-06-01

Process scale-up remains a considerable challenge for environmental applications of non-thermal plasmas. Undersanding the impact of reactor hydrodynamics in the performance of the process is a key step to overcome this challenge. In this work, we apply chemical engineering concepts to analyse the impact that different non-thermal plasma reactor configurations and regimes, such as laminar or plug flow, may have on the reactor performance. We do this in the particular context of the removal of pollutants by non-thermal plasmas, for which a simplified model is available. We generalise this model to different reactor configurations and, under certain hypotheses, we show that a reactor in the laminar regime may have a behaviour significantly different from one in the plug flow regime, often assumed in the non-thermal plasma literature. On the other hand, we show that a packed-bed reactor behaves very similarly to one in the plug flow regime. Beyond those results, the reader will find in this work a quick introduction to chemical reaction engineering concepts.

A feasibility work on the applications of MRE to automotive components

NASA Astrophysics Data System (ADS)

Kim, S. H.; Park, Y. J.; Cha, A. R.; Kim, G. W.; Bang, J. H.; Lim, C. S.; Choi, S. B.

2018-03-01

A feasibility work on the application of magneto-rheological elastomers (MREs) to automotive components, such as engine mounts is presented. While vehicle components require the high resonance frequency in terms of ride quality and handling, it is required to have the low resonance frequency to isolate the incoming vibration. With the conventional automotive technologies, it is challenging to combine these two conflicting performance trade-offs, ride quality including handling, and NVH (noise, vibration and harshness). Over the last decades, MREs, one of the new emerging smart materials, have been widely used to resolve this technical limitation. For example, an advanced engine mount was developed by using MRE to isolate the vibration transmitting from engines. In this paper, we will focus on rear cross member bushes, which is a key component for isolating the vibration from the road, and demonstrate their improved performance by utilizing MRE. The resonance frequency shift induced by the stiffness change of MRE will be presented through the frequency response functions estimated by simulation result.

Computer program for a four-cylinder-Stirling-engine controls simulation

NASA Technical Reports Server (NTRS)

Daniels, C. J.; Lorenzo, C. F.

1982-01-01

A four cylinder Stirling engine, transient engine simulation computer program is presented. The program is intended for controls analysis. The associated engine model was simplified to shorten computer calculation time. The model includes engine mechanical drive dynamics and vehicle load effects. The computer program also includes subroutines that allow: (1) acceleration of the engine by addition of hydrogen to the system, and (2) braking of the engine by short circuiting of the working spaces. Subroutines to calculate degraded engine performance (e.g., due to piston ring and piston rod leakage) are provided. Input data required to run the program are described and flow charts are provided. The program is modular to allow easy modification of individual routines. Examples of steady state and transient results are presented.

Navy Medicine. Volume 102, No. 4, Fall 2010

DTIC Science & Technology

2010-01-01

5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS...dental assistance to more than 4,000 Panama- nian citizens, immunized more than 800 animals and continued work on construction projects in local...patients, performed 859 surger- ies, issued 60,883 glasses, completed 22 engineering projects , participated in 86 community service projects (COM

HPC in a HEP lab: lessons learned from setting up cost-effective HPC clusters

NASA Astrophysics Data System (ADS)

Husejko, Michal; Agtzidis, Ioannis; Baehler, Pierre; Dul, Tadeusz; Evans, John; Himyr, Nils; Meinhard, Helge

2015-12-01

In this paper we present our findings gathered during the evaluation and testing of Windows Server High-Performance Computing (Windows HPC) in view of potentially using it as a production HPC system for engineering applications. The Windows HPC package, an extension of Microsofts Windows Server product, provides all essential interfaces, utilities and management functionality for creating, operating and monitoring a Windows-based HPC cluster infrastructure. The evaluation and test phase was focused on verifying the functionalities of Windows HPC, its performance, support of commercial tools and the integration with the users work environment. We describe constraints imposed by the way the CERN Data Centre is operated, licensing for engineering tools and scalability and behaviour of the HPC engineering applications used at CERN. We will present an initial set of requirements, which were created based on the above constraints and requests from the CERN engineering user community. We will explain how we have configured Windows HPC clusters to provide job scheduling functionalities required to support the CERN engineering user community, quality of service, user- and project-based priorities, and fair access to limited resources. Finally, we will present several performance tests we carried out to verify Windows HPC performance and scalability.

Experimental characterization of a small custom-built double-acting gamma-type stirling engine

NASA Astrophysics Data System (ADS)

Intsiful, Peter; Mensah, Francis; Thorpe, Arthur

This paper investigates characterization of a small custom-built double-acting gamma-type stirling engine. Stirling-cycle engine is a reciprocating energy conversion machine with working spaces operating under conditions of oscillating pressure and flow. These conditions may be due to compressibility as wells as pressure and temperature fluctuations. In standard literature, research indicates that there is lack of basic physics to account for the transport phenomena that manifest themselves in the working spaces of reciprocating engines. Previous techniques involve governing equations: mass, momentum and energy. Some authors use engineering thermodynamics. None of these approaches addresses this particular engine. A technique for observing and analyzing the behavior of this engine via parametric spectral profiles has been developed, using laser beams. These profiles enabled the generation of pv-curves and other trajectories for investigating the thermos-physical and thermos-hydrodynamic phenomena that manifest in the exchangers. The engine's performance was examined. The results indicate that with current load of 35.78A, electric power of 0.505 kW was generated at a speed of 240 rpm and 29.50 percent efficiency was obtained. Nasa grants to Howard University NASA/HBCU-NHRETU & CSTEA.

Rois Langner | NREL

Science.gov Websites

engineer in the Commercial Buildings Research Group at NREL since 2010. Her research efforts have focused optimize building design and performance for military and large commercial buildings. She has also worked continual energy improvement, and more recently is working to support the small commercial building sector

Propulsion Technology Lifecycle Operational Analysis

NASA Technical Reports Server (NTRS)

Robinson, John W.; Rhodes, Russell E.

2010-01-01

The paper presents the results of a focused effort performed by the members of the Space Propulsion Synergy Team (SPST) Functional Requirements Sub-team to develop propulsion data to support Advanced Technology Lifecycle Analysis System (ATLAS). This is a spreadsheet application to analyze the impact of technology decisions at a system-of-systems level. Results are summarized in an Excel workbook we call the Technology Tool Box (TTB). The TTB provides data for technology performance, operations, and programmatic parameters in the form of a library of technical information to support analysis tools and/or models. The lifecycle of technologies can be analyzed from this data and particularly useful for system operations involving long running missions. The propulsion technologies in this paper are listed against Chemical Rocket Engines in a Work Breakdown Structure (WBS) format. The overall effort involved establishing four elements: (1) A general purpose Functional System Breakdown Structure (FSBS). (2) Operational Requirements for Rocket Engines. (3) Technology Metric Values associated with Operating Systems (4) Work Breakdown Structure (WBS) of Chemical Rocket Engines The list of Chemical Rocket Engines identified in the WBS is by no means complete. It is planned to update the TTB with a more complete list of available Chemical Rocket Engines for United States (US) engines and add the Foreign rocket engines to the WBS which are available to NASA and the Aerospace Industry. The Operational Technology Metric Values were derived by the SPST Sub-team in the form of the TTB and establishes a database for users to help evaluate and establish the technology level of each Chemical Rocket Engine in the database. The Technology Metric Values will serve as a guide to help determine which rocket engine to invest technology money in for future development.

Comparing Composites.

ERIC Educational Resources Information Center

Mathras, Michael S.

1993-01-01

Presents an activity that models the work of chemical engineers. Students design, fabricate, and perform mechanical tests on plaster matrix composites and compare the strength to mass ratios of several products. (PR)

Engineering electrical properties of graphene: chemical approaches

NASA Astrophysics Data System (ADS)

Kim, Yong-Jin; Kim, Yuna; Novoselov, Konstantin; Hong, Byung Hee

2015-12-01

To ensure the high performance of graphene-based devices, it is necessary to engineer the electrical properties of graphene with enhanced conductivity, controlled work function, opened or closed bandgaps, etc. This can be performed by various non-covalent chemical approaches, including molecular adsorption, substrate-induced doping, polymerization on graphene, deposition of metallic thin films or nanoparticles, etc. In addition, covalent approaches such as the substitution of carbon atoms with boron or nitrogen and the functionalization with hydrogen or fluorine are useful to tune the bandgaps more efficiently, with better uniformity and stability. In this review, representative examples of chemically engineered graphene and its device applications will be reviewed, and remaining challenges will be discussed.

Summer graduate research program for interns in science and engineering

NASA Technical Reports Server (NTRS)

Lee, Clinton B.

1992-01-01

The goal of the 10 week graduate intern program was to increase the source of candidates for positions in science and engineering at the Goddard Space Flight Center. Students participating in this program submitted papers on the work they performed over the 10 week period and also filled out questionnaires on the program's effectiveness, their own performance, and suggestions on improvements. The topics covered by the student's papers include: microsoft excel applications; fast aurora zone analysis; injection seeding of a Q-switched alexandrite laser; use of high temperature superconductors; modifications on a communication interface board; modeling of space network activities; prediction of atmospheric ozone content; and applications of industrial engineering.

Summer graduate research program for interns in science and engineering

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

Lee, C.B.

1992-03-01

The goal of the 10 week graduate intern program was to increase the source of candidates for positions in science and engineering at the Goddard Space Flight Center. Students participating in this program submitted papers on the work they performed over the 10 week period and also filled out questionnaires on the program's effectiveness, their own performance, and suggestions on improvements. The topics covered by the student's papers include: microsoft excel applications; fast aurora zone analysis; injection seeding of a Q-switched alexandrite laser; use of high temperature superconductors; modifications on a communication interface board; modeling of space network activities; predictionmore » of atmospheric ozone content; and applications of industrial engineering.« less

Wave Engine Topping Cycle Assessment

NASA Technical Reports Server (NTRS)

Welch, Gerard E.

1996-01-01

The performance benefits derived by topping a gas turbine engine with a wave engine are assessed. The wave engine is a wave rotor that produces shaft power by exploiting gas dynamic energy exchange and flow turning. The wave engine is added to the baseline turboshaft engine while keeping high-pressure-turbine inlet conditions, compressor pressure ratio, engine mass flow rate, and cooling flow fractions fixed. Related work has focused on topping with pressure-exchangers (i.e., wave rotors that provide pressure gain with zero net shaft power output); however, more energy can be added to a wave-engine-topped cycle leading to greater engine specific-power-enhancement The energy addition occurs at a lower pressure in the wave-engine-topped cycle; thus the specific-fuel-consumption-enhancement effected by ideal wave engine topping is slightly lower than that effected by ideal pressure-exchanger topping. At a component level, however, flow turning affords the wave engine a degree-of-freedom relative to the pressure-exchanger that enables a more efficient match with the baseline engine. In some cases, therefore, the SFC-enhancement by wave engine topping is greater than that by pressure-exchanger topping. An ideal wave-rotor-characteristic is used to identify key wave engine design parameters and to contrast the wave engine and pressure-exchanger topping approaches. An aerodynamic design procedure is described in which wave engine design-point performance levels are computed using a one-dimensional wave rotor model. Wave engines using various wave cycles are considered including two-port cycles with on-rotor combustion (valved-combustors) and reverse-flow and through-flow four-port cycles with heat addition in conventional burners. A through-flow wave cycle design with symmetric blading is used to assess engine performance benefits. The wave-engine-topped turboshaft engine produces 16% more power than does a pressure-exchanger-topped engine under the specified topping constraints. Positive and negative aspects of wave engine topping in gas turbine engines are identified.

Example of a Human Factors Engineering approach to a medication administration work system: potential impact on patient safety.

PubMed

Beuscart-Zéphir, Marie-Catherine; Pelayo, Sylvia; Bernonville, Stéphanie

2010-04-01

The objectives of this paper are: In this approach, the implementation of such a complex IT solution is considered a major redesign of the work system. The paper describes the Human Factor (HF) tasks embedded in the project lifecycle: (1) analysis and modelling of the current work system and usability assessment of the medication CPOE solution; (2) HF recommendations for work re-design and usability recommendations for IT system re-engineering both aiming at a safer and more efficient work situation. Standard ethnographic methods were used to support the analysis of the current work system and work situations, coupled with cognitive task analysis methods and documents review. Usability inspection (heuristic evaluation) and both in-lab (simulated tasks) and on-site (real tasks) usability tests were performed for the evaluation of the CPOE candidate. Adapted software engineering models were used in combination with usual textual descriptions, tasks models and mock-ups to support the recommendations for work and product re-design. The analysis of the work situations identified different work organisations and procedures across the hospital's departments. The most important differences concerned the doctor-nurse communications and cooperation modes and the procedures for preparing and administering the medications. The assessment of the medication CPOE functions uncovered a number of usability problems including severe ones leading to impossible to detect or to catch errors. Models of the actual and possible distribution of tasks and roles were used to support decision making in the work design process. The results of the usability assessment were translated into requirements to support the necessary re-engineering of the IT application. The HFE approach to medication CPOE efficiently identifies and distinguishes currently unsafe or uncomfortable work situations that could obviously benefit from an IT solution from other work situations incorporating efficient work procedures that might be impaired by the implementation of the CPOE. In this context, a careful redesign of the work situation and of the entire work system is necessary to actually benefit from the installation of the product in terms of patient safety and human performances. In parallel, a usability assessment of the product to be implemented is mandatory to identify potentially dangerous usability flaws and to fix them before the installation. (c) 2009 Elsevier Ireland Ltd. All rights reserved.

Exhaust emissions reduction from diesel engine using combined Annona-Eucalyptus oil blends and antioxidant additive

NASA Astrophysics Data System (ADS)

Senthil, R.; Silambarasan, R.; Pranesh, G.

2017-03-01

The limited resources, rising petroleum prices and depletion of fossil fuel have now become a matter of great concern. Hence, there is an urgent need for researchers to find some alternate fuels which are capable of substituting partly or wholly the higher demanded conventional diesel fuel. Lot of research work has been conducted on diesel engine using biodiesel and its blends with diesel as an alternate fuel. Very few works have been done with combination of biodiesel-Eucalypts oil without neat diesel and this leads to lots of scope in this area. The aim of the present study is to analyze the performance and emission characteristics of a single cylinder, direct injection, compression ignition engine using eucalyptus oil-biodiesel as fuel. The presence of eucalyptus oil in the blend reduces the viscosity and improves the volatility of the blends. The methyl ester of Annona oil is blended with eucalypts oil in 10, 20, 30, 40 and 50 %. The performance and emission characteristics are evaluated by operating the engine at different loads. The performance characteristics such as brake thermal efficiency, brake specific fuel consumption and exhaust gas temperature are evaluated. The emission constituents measured are Carbon monoxide (CO), unburned hydrocarbons (HC), Oxides of nitrogen (NOx) and Smoke. It is found that A50-Eu50 (50 Annona + 50 % Eucalyptus oil) blend showed better performance and reduction in exhaust emissions. But, it showed a very marginal increase in NOx emission when compared to that of diesel. Therefore, in order to reduce the NOx emission, antioxidant additive (A-tocopherol acetate) is mixed with Annona-Eucalyptus oil blends in various proportions by which NOx emission is reduced. Hence, A50-Eu50 blend can be used as an alternate fuel for diesel engine without any modifications.

Folly Beach, South Carolina. Survey Report on Beach Erosion Control and Hurricane Protection.

DTIC Science & Technology

1980-03-28

ADAlI1 709 CORPS OF ENGINEERS CHARLESTON SC CHARLESTON DISTRICT F/G 13/2 MAR DFOLLY BEACH, SOUTH CAROLINA SURVEY REPORT ON BEACH EROSION CONT--ETCU...Army Corps of Engineers Charleston District P.O. Box 919, Charleston, S.C. 29402 _____________ S. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM...ELEMENT. PROJECT, TASK AREA & WORK UNIT NUMBERS U.S. Army Corps of Engineers Charleston District P.O. Box 919, Charleston, S.C. 29402 1t. CONTROLLING

General Performance Calculations for Gas Turbine Engines

DTIC Science & Technology

1946-08-01

by - D. H. Mailing on. B.So. June, 1946. In this monograph an attempt in made to summarise the theoretical work carried out during the past few...Engines 1.0 nBBPDPCTION ir’-> During the war years the gas turbine may be said to have come into its own, both as an engine already accepted and...The closer this second pressure ratio is to 1 the lower is the mnxlnwm output and also the pressure ratio r.t which that maximum occurs. Tho

SSME Post Test Diagnostic System: Systems Section

NASA Technical Reports Server (NTRS)

Bickmore, Timothy

1995-01-01

An assessment of engine and component health is routinely made after each test firing or flight firing of a Space Shuttle Main Engine (SSME). Currently, this health assessment is done by teams of engineers who manually review sensor data, performance data, and engine and component operating histories. Based on review of information from these various sources, an evaluation is made as to the health of each component of the SSME and the preparedness of the engine for another test or flight. The objective of this project - the SSME Post Test Diagnostic System (PTDS) - is to develop a computer program which automates the analysis of test data from the SSME in order to detect and diagnose anomalies. This report primarily covers work on the Systems Section of the PTDS, which automates the analyses performed by the systems/performance group at the Propulsion Branch of NASA Marshall Space Flight Center (MSFC). This group is responsible for assessing the overall health and performance of the engine, and detecting and diagnosing anomalies which involve multiple components (other groups are responsible for analyzing the behavior of specific components). The PTDS utilizes several advanced software technologies to perform its analyses. Raw test data is analyzed using signal processing routines which detect features in the data, such as spikes, shifts, peaks, and drifts. Component analyses are performed by expert systems, which use 'rules-of-thumb' obtained from interviews with the MSFC data analysts to detect and diagnose anomalies. The systems analysis is performed using case-based reasoning. Results of all analyses are stored in a relational database and displayed via an X-window-based graphical user interface which provides ranked lists of anomalies and observations by engine component, along with supporting data plots for each.

Decrease the Number of Glovebox Glove Breaches and Failures

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

Hurtle, Jackie C.

2013-12-24

Los Alamos National Laboratory (LANL) is committed to the protection of the workers, public, and environment while performing work and uses gloveboxes as engineered controls to protect workers from exposure to hazardous materials while performing plutonium operations. Glovebox gloves are a weak link in the engineered controls and are a major cause of radiation contamination events which can result in potential worker exposure and localized contamination making operational areas off-limits and putting programmatic work on hold. Each day of lost opportunity at Technical Area (TA) 55, Plutonium Facility (PF) 4 is estimated at $1.36 million. Between July 2011 and Junemore » 2013, TA-55-PF-4 had 65 glovebox glove breaches and failures with an average of 2.7 per month. The glovebox work follows the five step safety process promoted at LANL with a decision diamond interjected for whether or not a glove breach or failure event occurred in the course of performing glovebox work. In the event that no glove breach or failure is detected, there is an additional decision for whether or not contamination is detected. In the event that contamination is detected, the possibility for a glove breach or failure event is revisited.« less

Fuel properties and engine performance of biodiesel from waste cooking oil collected in Dhaka city

NASA Astrophysics Data System (ADS)

Islam, R. B.; Islam, R.; Uddin, M. N.; Ehsan, Md.

2016-07-01

Waste cooking oil can be a potential source of biodiesel that has least effect on the edible oil consumption. Increasing number of hotel-restaurants and more active monitoring by health authorities have increased the generation of waste cooking oil significantly in densely populated cities like Dhaka. If not used or disposed properly, waste cooking oil itself may generate lot of environmental issues. In this work, waste cooking oils from different restaurants within Dhaka City were collected and some relevant properties of these waste oils were measured. Based on the samples studied one with the highest potential as biodiesel feed was identified and processed for engine performance. Standard trans-esterification process was used to produce biodiesel from the selected waste cooking oil. Biodiesel blends of B20 and B40 category were made and tested on a single cylinder direct injection diesel engine. Engine performance parameters included - bhp, bsfc and exhaust emission for rated and part load conditions. Results give a quantitative assessment of the potential of using biodiesel from waste cooking oil as fuel for diesel engines in Bangladesh.

Progress on Variable Cycle Engines

NASA Technical Reports Server (NTRS)

Westmoreland, J. S.; Howlett, R. A.; Lohmann, R. P.

1979-01-01

Progress in the development and future requirements of the Variable Stream Control Engine (VSCE) are presented. The two most critical components of this advanced system for future supersonic transports, the high performance duct burner for thrust augmentation, and the low jet coannular nozzle were studied. Nozzle model tests substantiated the jet noise benefit associated with the unique velocity profile possible with a coannular nozzle system on a VSCE. Additional nozzle model performance tests have established high thrust efficiency levels only at takeoff and supersonic cruise for this nozzle system. An experimental program involving both isolated component and complete engine tests has been conducted for the high performance, low emissions duct burner with good results and large scale testing of these two components is being conducted using a F100 engine as the testbed for simulating the VSCE. Future work includes application of computer programs for supersonic flow fields to coannular nozzle geometries, further experimental testing with the duct burner segment rig, and the use of the Variable Cycle Engine (VCE) Testbed Program for evaluating the VSCE duct burner and coannular nozzle technologies.

A First Look at the DGEN380 Engine Acoustic Data from a Core-Noise Perspective

NASA Technical Reports Server (NTRS)

Hultgren, Lennart S.

2015-01-01

This work is a first look at acoustic data acquired in the NASA Glenn Research Center Aero-Acoustic Propulsion Laboratory using the Price Induction DGEN380 small turbofan engine, with particular emphasis on broadband combustor (core) noise. Combustor noise is detected by using a two-signal source separation technique employing one engine-internal sensor and one semi-far-field microphone. Combustor noise is an important core-noise component and is likely to become a more prominent contributor to overall airport community noise due to turbofan design trends, expected aircraft configuration changes, and advances in fan-noise-mitigation techniques. This work was carried out under the NASA Fundamental Aeronautics Program, Fixed Wing Project, Quiet Performance Subproject

Active learning in the space engineering education at Technical University of Madrid

NASA Astrophysics Data System (ADS)

Rodríguez, Jacobo; Laverón-Simavilla, Ana; Lapuerta, Victoria; Ezquerro Navarro, Jose Miguel; Cordero-Gracia, Marta

This work describes the innovative activities performed in the field of space education at the Technical University of Madrid (UPM), in collaboration with the center engaged by the European Space Agency (ESA) in Spain to support the operations for scientific experiments on board the International Space Station (E-USOC). These activities have been integrated along the last academic year of the Aerospatiale Engineering degree. A laboratory has been created, where the students have to validate and integrate the subsystems of a microsatellite by using demonstrator satellites. With the acquired skills, the students participate in a training process centered on Project Based Learning, where the students work in groups to perform the conceptual design of a space mission, being each student responsible for the design of a subsystem of the satellite and another one responsible of the mission design. In parallel, the students perform a training using a ground station, installed at the E-USOC building, which allow them to learn how to communicate with satellites, how to download telemetry and how to process the data. This also allows students to learn how the E-USOC works. Two surveys have been conducted to evaluate the impact of these techniques in the student engineering skills and to know the degree of satisfaction of students with respect to the use of these learning methodologies.

A novel gate and drain engineered charge plasma tunnel field-effect transistor for low sub-threshold swing and ambipolar nature

NASA Astrophysics Data System (ADS)

Yadav, Dharmendra Singh; Raad, Bhagwan Ram; Sharma, Dheeraj

2016-12-01

In this paper, we focus on the improvement of figures of merit for charge plasma based tunnel field-effect transistor (TFET) in terms of ON-state current, threshold voltage, sub-threshold swing, ambipolar nature, and gate to drain capacitance which provides better channel controlling of the device with improved high frequency response at ultra-low supply voltages. Regarding this, we simultaneously employ work function engineering on the drain and gate electrode of the charge plasma TFET. The use of gate work function engineering modulates the barrier on the source/channel interface leads to improvement in the ON-state current, threshold voltage, and sub-threshold swing. Apart from this, for the first time use of work function engineering on the drain electrode increases the tunneling barrier for the flow of holes on the drain/channel interface, it results into suppression of ambipolar behavior. The lowering of gate to drain capacitance therefore enhanced high frequency parameters. Whereas, the presence of dual work functionality at the gate electrode and over the drain region improves the overall performance of the charge plasma based TFET.

Short Range Wireless Power Transfer (WPT) for UAV/UAS Battery Charging - Phase 1

DTIC Science & Technology

2014-12-01

WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) AND ADDRESS(ES) Department of Electrical and Computer Engineering 8...Research Computer Engineering iii THIS PAGE INTENTIONALLY LEFT BLANK iv ABSTRACT The...battery charging, spacecraft recharging and station keeping, and direct propulsion of UAVs and hovering airships . The client antenna is usually of low

Bio-Nanotechnology Infrastructure and Technology Oriented Research

DTIC Science & Technology

2008-07-17

4) dissemination of the accomplishments through filing patents, publishing refereed papers and presenting at international conferences and meetings...NUMBER 6. AUTHOR(S) Kinzy Jones 5d. PROJECT NUMBER Florida International University ADVANCED MATERIALS ENGINEERING RESERACH INSTITUTE 5e...University ADVANCED MATERIALS ENGINEERING RESERACH INSTITUTE 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES

Integrating Environmental Management in Chemical Engineering Education by Introducing an Environmental Management System in the Student's Laboratory

ERIC Educational Resources Information Center

Montanes, Maria T.; Palomares, Antonio E.

2008-01-01

In this work we show how specific challenges related to sustainable development can be integrated into chemical engineering education by introducing an environmental management system in the laboratory where the students perform their experimental lessons. It is shown how the system has been developed and implemented in the laboratory, what role…

REDUCING ENERGY AND SPACE REQUIREMENTS BY ELECTROSTATIC AUGMENTATION OF A PULSE-JET FABRIC FILTER

EPA Science Inventory

In work performed several years ago by EPA's research lab then known as Air and Energy Engineering Research Laboratory (EPA/AEERL), small-scale testing and modeling of electrostatically stimulated fabric filtration (ESFF) has indicated than substantial performance benefits could ...

Fuel property effects on USN gas turbine combustors

NASA Technical Reports Server (NTRS)

Masters, A. I.; Mosier, S. A.; Nowack, C. J.

1984-01-01

For several years the Department of Defense has been sponsoring fuel accommodation investigations with gas turbine engine manufacturers and supporting organizations to quantify the effect of changes in fuel properties and characteristics on the operation and performance of military engine components and systems. Inasmuch as there are many differences in hardware between the operational engines in the military inventories, due to differences in design philosophy and requirements, efforts were initially expended to acquire fuel effects data from rigs simulating the hot sections of these different engines. Correlations were then sought using the data acquired to produce more general, generic relationships that could be applied to all military gas turbine engines regardless of their origin. Finally, models could be developed from these correlations that could predict the effect of fuel property changes on current and future engines. This presentation describes some of the work performed by Pratt and Whitney Aircraft, under Naval Air Propulsion Center sponsorship, to determine the effect of fuel properties on the hot section and fuel system of the Navy's TF30-P-414 gas turbine engine.

Performance Analysis of AN Engine Mount Featuring ER Fluids and Piezoactuators

NASA Astrophysics Data System (ADS)

Choi, S. H.; Choi, Y. T.; Choi, S. B.; Cheong, C. C.

Conventional rubber mounts and various types of passive or semi-active hydraulic engine mounts for a passenger vehicle have their own functional aims on the limited frequency band in the broad engine operating frequency range. In order to achieve high system performance over all frequency ranges of the engine operation, a new type of engine mount featuring electro-rheological(ER) fluids and piezoactuators is proposed in this study. A mathematical model of the proposed engine mount is derived using the bond graph method which is inherently adequate to model the interconnected hydromechanical system. In the low frequency domain, the ER fluid is activated upon imposing an electric field for vibration isolation while the piezoactuator is activated in the high frequency domain. A neuro-control algorithm is utilized to determine control electric field for the ER fluid, and H∞ control technique is adopted for the piezoactuator Comparative works between the proposed and single-actuating(ER fluid only or piezoactuator only) engine mounts are undertaken by evaluating force transmissibility over a wide operating frequency range.

Modelling and Simulation for Requirements Engineering and Options Analysis

DTIC Science & Technology

2010-05-01

should be performed to work successfully in the domain; and process-based techniques model the processes that occur in the work domain. There is a crisp ...acad/sed/sedres/ dm /erg/cwa. DRDC Toronto CR 2010-049 39 23. Can the current technique for developing simulation models for assessments

75 FR 27857 - Aviation Rulemaking Advisory Committee; Transport Airplane and Engine Issue Area-New Task

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-18

... (autopilot) and performance and handling qualities in icing conditions to improve transport airplane... the existing Avionics Systems Harmonization Working Group. The Task ARAC is initially tasked with... working group will be expected to provide a report that addresses the following low speed alerting...

NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 35: The use of computer networks in aerospace engineering

NASA Technical Reports Server (NTRS)

Bishop, Ann P.; Pinelli, Thomas E.

1995-01-01

This research used survey research to explore and describe the use of computer networks by aerospace engineers. The study population included 2000 randomly selected U.S. aerospace engineers and scientists who subscribed to Aerospace Engineering. A total of 950 usable questionnaires were received by the cutoff date of July 1994. Study results contribute to existing knowledge about both computer network use and the nature of engineering work and communication. We found that 74 percent of mail survey respondents personally used computer networks. Electronic mail, file transfer, and remote login were the most widely used applications. Networks were used less often than face-to-face interactions in performing work tasks, but about equally with reading and telephone conversations, and more often than mail or fax. Network use was associated with a range of technical, organizational, and personal factors: lack of compatibility across systems, cost, inadequate access and training, and unwillingness to embrace new technologies and modes of work appear to discourage network use. The greatest positive impacts from networking appear to be increases in the amount of accurate and timely information available, better exchange of ideas across organizational boundaries, and enhanced work flexibility, efficiency, and quality. Involvement with classified or proprietary data and type of organizational structure did not distinguish network users from nonusers. The findings can be used by people involved in the design and implementation of networks in engineering communities to inform the development of more effective networking systems, services, and policies.

Adaptive Development

NASA Technical Reports Server (NTRS)

2005-01-01

The goal of this research is to develop and demonstrate innovative adaptive seal technologies that can lead to dramatic improvements in engine performance, life, range, and emissions, and enhance operability for next generation gas turbine engines. This work is concentrated on the development of self-adaptive clearance control systems for gas turbine engines. Researchers have targeted the high-pressure turbine (HPT) blade tip seal location for following reasons: Current active clearance control (ACC) systems (e.g., thermal case-cooling schemes) cannot respond to blade tip clearance changes due to mechanical, thermal, and aerodynamic loads. As such they are prone to wear due to the required tight running clearances during operation. Blade tip seal wear (increased clearances) reduces engine efficiency, performance, and service life. Adaptive sealing technology research has inherent impact on all envisioned 21st century propulsion systems (e.g. distributed vectored, hybrid and electric drive propulsion concepts).

HPT Clearance Control: Intelligent Engine Systems-Phase 1

NASA Technical Reports Server (NTRS)

2005-01-01

The following work has been completed to satisfy the Phase I Deliverables for the "HPT Clearance Control" project under NASA GRC's "Intelligent Engine Systems" program: (1) Need for the development of an advanced HPT ACC system has been very clearly laid out, (2) Several existing and potential clearance control systems have been reviewed, (3) A scorecard has been developed to document the system, performance (fuel burn, range, payload, etc.), thermal, and mechanical characteristics of the existing clearance control systems, (4) Engine size and flight cycle selection for the advanced HPT ACC system has been reviewed with "large engine"/"long range mission" combination showing the most benefit, (5) A scoring criteria has been developed to tie together performance parameters for an objective, data driven comparison of competing systems, and (6) The existing HPT ACC systems have been scored based on this scoring system.

Production of succinic acid by metabolically engineered microorganisms.

PubMed

Ahn, Jung Ho; Jang, Yu-Sin; Lee, Sang Yup

2016-12-01

Succinic acid (SA) has been recognized as one of the most important bio-based building block chemicals due to its numerous potential applications. For the economical bio-based production of SA, extensive research works have been performed on developing microbial strains by metabolic engineering as well as fermentation and downstream processes. Here we review metabolic engineering strategies applied for bio-based production of SA using representative microorganisms, including Saccharomyces cerevisiae, Pichia kudriavzevii, Escherichia coli, Mannheimia succiniciproducens, Basfia succiniciproducens, Actinobacillus succinogenes, and Corynebacterium glutamicum. In particular, strategies employed for developing engineered strains of these microorganisms leading to the best performance indices (titer, yield, and productivity) are showcased based on the published papers as well as patents. Those processes currently under commercialization are also analyzed and future perspectives are provided. Copyright © 2016 Elsevier Ltd. All rights reserved.

Thermodynamic and Mechanical Analysis of a Thermomagnetic Rotary Engine

NASA Astrophysics Data System (ADS)

Fajar, D. M.; Khotimah, S. N.; Khairurrijal

2016-08-01

A heat engine in magnetic system had three thermodynamic coordinates: magnetic intensity ℋ, total magnetization ℳ, and temperature T, where the first two of them are respectively analogous to that of gaseous system: pressure P and volume V. Consequently, Carnot cycle that constitutes the principle of a heat engine in gaseous system is also valid on that in magnetic system. A thermomagnetic rotary engine is one model of it that was designed in the form of a ferromagnetic wheel that can rotates because of magnetization change at Curie temperature. The study is aimed to describe the thermodynamic and mechanical analysis of a thermomagnetic rotary engine and calculate the efficiencies. In thermodynamic view, the ideal processes are isothermal demagnetization, adiabatic demagnetization, isothermal magnetization, and adiabatic magnetization. The values of thermodynamic efficiency depend on temperature difference between hot and cold reservoir. In mechanical view, a rotational work is determined through calculation of moment of inertia and average angular speed. The value of mechanical efficiency is calculated from ratio between rotational work and heat received by system. The study also obtains exergetic efficiency that states the performance quality of the engine.

Update on Risk Reduction Activities for a Liquid Advanced Booster for NASA's Space Launch System

NASA Technical Reports Server (NTRS)

Crocker, Andrew M.; Greene, William D.

2017-01-01

The stated goals of NASA's Research Announcement for the Space Launch System (SLS) Advanced Booster Engineering Demonstration and/or Risk Reduction (ABEDRR) are to reduce risks leading to an affordable Advanced Booster that meets the evolved capabilities of SLS and enable competition by mitigating targeted Advanced Booster risks to enhance SLS affordability. Dynetics, Inc. and Aerojet Rocketdyne (AR) formed a team to offer a wide-ranging set of risk reduction activities and full-scale, system-level demonstrations that support NASA's ABEDRR goals. During the ABEDRR effort, the Dynetics Team has modified flight-proven Apollo-Saturn F-1 engine components and subsystems to improve affordability and reliability (e.g., reduce parts counts, touch labor, or use lower cost manufacturing processes and materials). The team has built hardware to validate production costs and completed tests to demonstrate it can meet performance requirements. State-of-the-art manufacturing and processing techniques have been applied to the heritage F-1, resulting in a low recurring cost engine while retaining the benefits of Apollo-era experience. NASA test facilities have been used to perform low-cost risk-reduction engine testing. In early 2014, NASA and the Dynetics Team agreed to move additional large liquid oxygen/kerosene engine work under Dynetics' ABEDRR contract. Also led by AR, the objectives of this work are to demonstrate combustion stability and measure performance of a 500,000 lbf class Oxidizer-Rich Staged Combustion (ORSC) cycle main injector. A trade study was completed to investigate the feasibility, cost effectiveness, and technical maturity of a domestically-produced engine that could potentially both replace the RD-180 on Atlas V and satisfy NASA SLS payload-to-orbit requirements via an advanced booster application. Engine physical dimensions and performance parameters resulting from this study provide the system level requirements for the ORSC risk reduction test article. The test article is scheduled to complete fabrication and assembly soon and continue testing through late 2019. Dynetics has also designed, developed, and built innovative tank and structure assemblies using friction stir welding to leverage recent NASA investments in manufacturing tools, facilities, and processes, significantly reducing development and recurring costs. The full-scale cryotank assembly was used to verify the structural design and prove affordable processes. Dynetics performed hydrostatic and cryothermal proof tests on the assembly to verify the assembly meets performance requirements..

Engineering microbes for isoprene production.

PubMed

Ye, Lidan; Lv, Xiaomei; Yu, Hongwei

2016-11-01

Isoprene is facing a growing global market due to its wide industrial applications. Current industrial production of isoprene is almost entirely petroleum-based, which is influenced by the shrinking C5 supply, while the natural emission of isoprene is predominantly contributed by plants. To bridge the need gap, a highly efficient fermentation-based process for isoprene production might be a suitable and sustainable solution, and extensive research works have been performed to achieve this goal. Here we review the accomplishments in this field by summarizing the history and prospects of microbial isoprene production. The natural producers and biosynthesis pathways of isoprene, the key enzyme isoprene synthase and the metabolic engineering strategies adopted for developing isoprene-producing microorganisms are introduced. In particular, strategies employed for achieving engineered strains with improved performance indices are discussed based on the published papers and patents. The perspectives on further performance improvements and potential future strategies are presented as well. Copyright © 2016 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

The impact of the weather conditions on the cooling performance of the heat pump driven by an internal natural gas combustion engine

NASA Astrophysics Data System (ADS)

Janovcová, Martina; Jandačka, Jozef; Malcho, Milan

2015-05-01

Market with sources of heat and cold offers unlimited choice of different power these devices, design technology, efficiency and price categories. New progressive technologies are constantly discovering, about which is still little information, which include heat pumps powered by a combustion engine running on natural gas. A few pieces of these installations are in Slovakia, but no studies about their work and effectiveness under real conditions. This article deals with experimental measurements of gas heat pump efficiency in cooling mode. Since the gas heat pump works only in system air - water, air is the primary low - energy source, it is necessary to monitor the impact of the climate conditions for the gas heat pump performance.

Architecture engineering of hierarchically porous chitosan/vacuum-stripped graphene scaffold as bioanode for high performance microbial fuel cell.

PubMed

He, Ziming; Liu, Jing; Qiao, Yan; Li, Chang Ming; Tan, Timothy Thatt Yang

2012-09-12

The bioanode is the defining feature of microbial fuel cell (MFC) technology and often limits its performance. In the current work, we report the engineering of a novel hierarchically porous architecture as an efficient bioanode, consisting of biocompatible chitosan and vacuum-stripped graphene (CHI/VSG). With the hierarchical pores and unique VSG, an optimized bioanode delivered a remarkable maximum power density of 1530 mW m(-2) in a mediator-less MFC, 78 times higher than a carbon cloth anode.

Robotic Processing Of Rocket-Engine Nozzles

NASA Technical Reports Server (NTRS)

Gilbert, Jeffrey L.; Maslakowski, John E.; Gutow, David A.; Deily, David C.

1994-01-01

Automated manufacturing cell containing computer-controlled robotic processing system developed to implement some important related steps in fabrication of rocket-engine nozzles. Performs several tedious and repetitive fabrication, measurement, adjustment, and inspection processes and subprocesses now performed manually. Offers advantages of reduced processing time, greater consistency, excellent collection of data, objective inspections, greater productivity, and simplified fixturing. Also affords flexibility: by making suitable changes in hardware and software, possible to modify process and subprocesses. Flexibility makes work cell adaptable to fabrication of heat exchangers and other items structured similarly to rocket nozzles.

Mission Evaluation Room Intelligent Diagnostic and Analysis System (MIDAS)

NASA Technical Reports Server (NTRS)

Pack, Ginger L.; Falgout, Jane; Barcio, Joseph; Shnurer, Steve; Wadsworth, David; Flores, Louis

1994-01-01

The role of Mission Evaluation Room (MER) engineers is to provide engineering support during Space Shuttle missions, for Space Shuttle systems. These engineers are concerned with ensuring that the systems for which they are responsible function reliably, and as intended. The MER is a central facility from which engineers may work, in fulfilling this obligation. Engineers participate in real-time monitoring of shuttle telemetry data and provide a variety of analyses associated with the operation of the shuttle. The Johnson Space Center's Automation and Robotics Division is working to transfer advances in intelligent systems technology to NASA's operational environment. Specifically, the MER Intelligent Diagnostic and Analysis System (MIDAS) project provides MER engineers with software to assist them with monitoring, filtering and analyzing Shuttle telemetry data, during and after Shuttle missions. MIDAS off-loads to computers and software, the tasks of data gathering, filtering, and analysis, and provides the engineers with information which is in a more concise and usable form needed to support decision making and engineering evaluation. Engineers are then able to concentrate on more difficult problems as they arise. This paper describes some, but not all of the applications that have been developed for MER engineers, under the MIDAS Project. The sampling described herewith was selected to show the range of tasks that engineers must perform for mission support, and to show the various levels of automation that have been applied to assist their efforts.

The Cutting Edge of High-Temperature Composites

NASA Technical Reports Server (NTRS)

2006-01-01

NASA s Ultra-Efficient Engine Technology (UEET) program was formed in 1999 at Glenn Research Center to manage an important national propulsion program for the Space Agency. The UEET program s focus is on developing innovative technologies to enable intelligent, environmentally friendly, and clean-burning turbine engines capable of reducing harmful emissions while maintaining high performance and increasing reliability. Seven technology projects exist under the program, with each project working towards specific goals to provide new technology for propulsion. One of these projects, Materials and Structures for High Performance, is concentrating on developing and demonstrating advanced high-temperature materials to enable high-performance, high-efficiency, and environmentally compatible propulsion systems. Materials include ceramic matrix composite (CMC) combustor liners and turbine vanes, disk alloys, turbine airfoil material systems, high-temperature polymer matrix composites, and lightweight materials for static engine structures.

Recent advances in systems metabolic engineering tools and strategies.

PubMed

Chae, Tong Un; Choi, So Young; Kim, Je Woong; Ko, Yoo-Sung; Lee, Sang Yup

2017-10-01

Metabolic engineering has been playing increasingly important roles in developing microbial cell factories for the production of various chemicals and materials to achieve sustainable chemical industry. Nowadays, many tools and strategies are available for performing systems metabolic engineering that allows systems-level metabolic engineering in more sophisticated and diverse ways by adopting rapidly advancing methodologies and tools of systems biology, synthetic biology and evolutionary engineering. As an outcome, development of more efficient microbial cell factories has become possible. Here, we review recent advances in systems metabolic engineering tools and strategies together with accompanying application examples. In addition, we describe how these tools and strategies work together in simultaneous and synergistic ways to develop novel microbial cell factories. Copyright © 2017 Elsevier Ltd. All rights reserved.

KSC-2011-6523

NASA Image and Video Library

2011-08-19

CAPE CANAVERAL, Fla. -- In Orbiter Processing Facility-2 at NASA’s Kennedy Space Center in Florida, technicians monitor the progress as they use a Hyster forklift to position an engine removal device on Engine #3 on space shuttle Atlantis. Inside the aft section, a technician disconnects hydraulic, fluid and electrical lines. The forklift will be used to remove the engine and transport it to the Engine Shop for possible future use. Each of the three space shuttle main engines is 14 feet long and weighs 7,800 pounds. Removal of the space shuttle main engines is part of the Transition and Retirement work that is being performed in order to prepare Atlantis for eventual display at the Kennedy Space Center Visitor Complex in Florida. Photo credit: Frankie Martin

STS-26 Discovery, OV-103, SSME (2019) installed in position number one at KSC

NASA Image and Video Library

1988-01-10

S88-29076 (10 Jan 1988) --- KSC employees work together to carefully guide a 7,000 pound main engine into the number one position in Discovery's aft compartment. Because of the engine's weight and size, special handling equipment is needed to perform the installation. Discovery is currently being prepared for the upcoming STS-26 mission in bay 1 of the Orbiter Processing Facility. This engine, 2019, arrived at KSC on Jan. 6 and was installed Jan. 10. The other two engines are scheduled to be installed later this month. The shuttle's three main liquid fueled engines provide the main propulsion for the orbiter vehicle. The cluster of three engines operate in parallel with the solid rocket boosters during the initial ascent.

Assessing the role of mini-applications in predicting key performance characteristics of scientific and engineering applications

DOE PAGES

Barrett, R. F.; Crozier, P. S.; Doerfler, D. W.; ...

2014-09-28

Computational science and engineering application programs are typically large, complex, and dynamic, and are often constrained by distribution limitations. As a means of making tractable rapid explorations of scientific and engineering application programs in the context of new, emerging, and future computing architectures, a suite of miniapps has been created to serve as proxies for full scale applications. Each miniapp is designed to represent a key performance characteristic that does or is expected to significantly impact the runtime performance of an application program. In this paper we introduce a methodology for assessing the ability of these miniapps to effectively representmore » these performance issues. We applied this methodology to four miniapps, examining the linkage between them and an application they are intended to represent. Herein we evaluate the fidelity of that linkage. This work represents the initial steps required to begin to answer the question, ''Under what conditions does a miniapp represent a key performance characteristic in a full app?''« less

Contributions Regarding the Aircraft Nuclear Propulsion

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

Mitrica, Bogdan; Petre, Marian; Dima, Mihai Octavian

2010-01-21

The possibility to use a nuclear reactor for airplanes propulsion was investigated taking in to account 2 possible solutions: the direct cycle (where the fluid pass through the reactor's core) and the indirect cycle (where the fluid is passing through a heat exchanger). Taking in to account the radioprotection problems, the only realistic solution seems to be the indirect cycle, where the energy transfer should be performed by a heat exchanger that must work at very high speed of the fluid. The heat exchanger will replace the classical burning room. We had performed a more precise theoretical study for themore » nuclear jet engine regarding the performances of the nuclear reactor, of the heat exchanger and of the jet engine. It was taken in to account that in the moment when the burning room is replaced by a heat exchanger, a new model for gasodynamic process from the engine must be performed. Studies regarding the high flow speed heat transfer were performed.« less

Impact of inlet coherent motions on compressor performance

NASA Astrophysics Data System (ADS)

Forlese, Jacopo; Spoleti, Giovanni

2017-08-01

Automotive engine induction systems may be characterized by significant flow angularity and total pressure distortion at the compressor inlet. The impact of the swirl on compressor performance should be quantified to guide the design of the induction systems. In diesel engines, the presence of a valve for flow reduction and control of low pressure EGR recirculation could generate coherent motion and influence the performance of the compressor. Starting from experimental map, the compressor speed-lines have been simulated using a 3D CFD commercial code imposing different concept motion at the inlet. The swirl intensity, the direction and the number of vortices have been imposed in order to taking into account some combinations. Finally, a merit function has been defined to evaluate the performance of the compressor with the defined swirl concepts. The aim of the current work is to obtain an indication on the effect of a swirling motion at the compressor inlet on the engine performance and provide a guideline to the induction system design.

Work demands are related to mental health problems for older engine room officers.

PubMed

Rydstedt, Leif W; Lundh, Monica

2012-01-01

The aim of the present study was to analyse the main and interaction effects of age and psychosocial work demands on mental wellbeing in a sample (N = 685; age M = 47 years) of engine room officers in the Swedish merchant fleet. As expected, work demands were highly related to general mental health as well as to perceived stress, while the main effect of age only related significantly to perceived stress. The interaction effects between high work demands and high age significantly explained the variance of general mental health as well as perceived stress. The results can be understood as a consequence of the rapid technological and organisational development in the shipping industry and suggest that it ought be of high priority to provide older employees with work-related resources to support their long-term work performance as well as their health and wellbeing.

Experimental Investigation on The Electromagnetic Clutch Water pump and Pneumatic Compressor for Improving the Efficiency of an Engine

NASA Astrophysics Data System (ADS)

Kumarasubramanian, R.; Xavier, Goldwin; Nishanthi, W. Mary; Rajasekar, R.

2017-05-01

Considering the fuel crises today many work and research were conducted to reduce the fuel consumption of the internal combustion engine. The fuel consumption of an internal combustion engine can be relatively reduced by use of the electromagnetic clutch water pump and pneumatic compressor. Normally in an engine, the water pump is driven by the crankshaft, with an aid of belt, for the circulation of the water for the cooling process. The circulation of coolant is resisted by the thermostat valve, while the temperature inside the coolant jacket of the engine is below 375K the thermostat is closed only above 375K it tends to open. But water pump run continuously even when thermostat is closed. In pneumatic braking system, pneumatic or air compressor purpose is to compress the air and stored into the storage tank for the brake operation. When the air pressure of the storage tanks gets increases above its storage capacity pressure is regulated by governor, by passing them to atmosphere. Such unnecessary work of this water pump and air compressor can be minimized by use of the electromagnetic clutch water pump and air compressor. The European Driving Cycle is used to evaluate the performance of this water pump and air compressor when used in an engine. The result shows that the fuel economy of the engine while using electromagnetic water pump and pneumatic compressor were improved by 8.0% compared with conventional types which already exist. The application of these electromagnetic water pump and pneumatic compressor are expected to contribute for the improvement of engine performance because of their effect in reduction of the rate of fuel consumption.

Universality of maximum-work efficiency of a cyclic heat engine based on a finite system of ultracold atoms.

PubMed

Ye, Zhuolin; Hu, Yingying; He, Jizhou; Wang, Jianhui

2017-07-24

We study the performance of a cyclic heat engine which uses a small system with a finite number of ultracold atoms as its working substance and works between two heat reservoirs at constant temperatures T h and T c (

Biomedical engineering tasks. [electrode development for electrocardiography and electroencephalography

NASA Technical Reports Server (NTRS)

1972-01-01

Electrocardiographic and vectorcardiographic bioinstrumentation work centered on the development of a new electrode system harness for Project Skylab. Evaluation of several silver electrode configurations proved superior impedance voltage performance for silver/silver chloride electrodes mounted flush by using a paste adhesive. A portable ECG processor has been designed and a breadboard unit has been built to sample ECG input data at a rate of 500 samples per second for arrhythmia detection. A small real time display driver program has been developed for statistical analysis on selected QPS features. Engineering work on a sleep monitoring cap assembly continued.

Effect of leading edge sweep on the performance of cavitating inducer of LOX booster turbopump used in semicryogenic engine

NASA Astrophysics Data System (ADS)

Mishra, Arpit; Ghosh, Parthasarathi

2017-02-01

As a part of the developmental effort towards the realization of a staged combustion cycle based liquid rocket engine, a program on simulation of the LOX booster pump for performance characterization has been taken up. Earlier reported work shows that the pump inducer works satisfactorily under cavitating conditions for the throttling range varying from 90% to 113%. However stall occurs below 90% of the designed flow rate which is to be strongly associated with the inlet backflow vortices due to flow separation [1]. It is envisaged that leading edge sweep may help in to controls the incipience and growth of the backflow vortices at the inlet leading edge tip of axial flow inducer leading to a wider operating range. In this paper, steady state 3D CFD analysis of rotating inducer is performed to examine the effect of leading edge sweep on the performance of axial flow LOX pump inducer using ANSYS® CFX and has been compared with the performance of the inducer reported by Mishra and Ghosh [1].

Thermal Energy Conversion Branch

NASA Technical Reports Server (NTRS)

Bielozer, Matthew C.; Schreiber, Jeffrey, G.; Wilson, Scott D.

2004-01-01

The Thermal Energy Conversion Branch (5490) leads the way in designing, conducting, and implementing research for the newest thermal systems used in space applications at the NASA Glenn Research Center. Specifically some of the most advanced technologies developed in this branch can be broken down into four main areas: Dynamic Power Systems, Primary Solar Concentrators, Secondary Solar Concentrators, and Thermal Management. Work was performed in the Dynamic Power Systems area, specifically the Stirling Engine subdivision. Today, the main focus of the 5490 branch is free-piston Stirling cycle converters, Brayton cycle nuclear reactors, and heat rejection systems for long duration mission spacecraft. All space exploring devices need electricity to operate. In most space applications, heat energy from radioisotopes is converted to electrical power. The Radioisotope Thermoelectric Generator (RTG) already supplies electricity for missions such as the Cassini Spacecraft. The focus of today's Stirling research at GRC is aimed at creating an engine that can replace the RTG. The primary appeal of the Stirling engine is its high system efficiency. Because it is so efficient, the Stirling engine will significantly reduce the plutonium fuel mission requirements compared to the RTG. Stirling is also being considered for missions such as the lunar/Mars bases and rovers. This project has focused largely on Stirling Engines of all types, particularly the fluidyne liquid piston engine. The fluidyne was developed by Colin D. West. This engine uses the same concepts found in any type of Stirling engine, with the exception of missing mechanical components. All the working components are fluid. One goal was to develop and demonstrate a working Stirling Fluidyne Engine at the 2nd Annual International Energy Conversion Engineering Conference in Providence, Rhode Island.

Experimental investigation of performance and emissions of a VCR diesel engine fuelled with n-butanol diesel blends under varying engine parameters.

PubMed

Nayyar, Ashish; Sharma, Dilip; Soni, Shyam Lal; Mathur, Alok

2017-09-01

The continuous rise in the cost of fossil fuels as well as in environmental pollution has attracted research in the area of clean alternative fuels for improving the performance and emissions of internal combustion (IC) engines. In the present work, n-butanol is treated as a bio-fuel and investigations have been made to evaluate the feasibility of replacing diesel with a suitable n-butanol-diesel blend. In the current research, an experimental investigation was carried out on a variable compression ratio CI engine with n-butanol-diesel blends (10-25% by volume) to determine the optimum blending ratio and optimum operating parameters of the engine for reduced emissions. The best results of performance and emissions were observed for 20% n-butanol-diesel blend (B20) at a higher compression ratio as compared to diesel while keeping the other parameters unchanged. The observed deterioration in engine performance was within tolerable limits. The reductions in smoke, nitrogen oxides (NO x ), and carbon monoxide (CO) were observed up to 56.52, 17.19, and 30.43%, respectively, for B20 in comparison to diesel at rated power. However, carbon dioxide (CO 2 ) and hydrocarbons (HC) were found to be higher by 17.58 and 15.78%, respectively, for B20. It is concluded that n-butanol-diesel blend would be a potential fuel to control emissions from diesel engines. Graphical abstract ᅟ.

Performance evaluation of the Engineering Analysis and Data Systems (EADS) 2

NASA Technical Reports Server (NTRS)

Debrunner, Linda S.

1994-01-01

The Engineering Analysis and Data System (EADS)II (1) was installed in March 1993 to provide high performance computing for science and engineering at Marshall Space Flight Center (MSFC). EADS II increased the computing capabilities over the existing EADS facility in the areas of throughput and mass storage. EADS II includes a Vector Processor Compute System (VPCS), a Virtual Memory Compute System (CFS), a Common Output System (COS), as well as Image Processing Station, Mini Super Computers, and Intelligent Workstations. These facilities are interconnected by a sophisticated network system. This work considers only the performance of the VPCS and the CFS. The VPCS is a Cray YMP. The CFS is implemented on an RS 6000 using the UniTree Mass Storage System. To better meet the science and engineering computing requirements, EADS II must be monitored, its performance analyzed, and appropriate modifications for performance improvement made. Implementing this approach requires tool(s) to assist in performance monitoring and analysis. In Spring 1994, PerfStat 2.0 was purchased to meet these needs for the VPCS and the CFS. PerfStat(2) is a set of tools that can be used to analyze both historical and real-time performance data. Its flexible design allows significant user customization. The user identifies what data is collected, how it is classified, and how it is displayed for evaluation. Both graphical and tabular displays are supported. The capability of the PerfStat tool was evaluated, appropriate modifications to EADS II to optimize throughput and enhance productivity were suggested and implemented, and the effects of these modifications on the systems performance were observed. In this paper, the PerfStat tool is described, then its use with EADS II is outlined briefly. Next, the evaluation of the VPCS, as well as the modifications made to the system are described. Finally, conclusions are drawn and recommendations for future worked are outlined.

How to Do Science From an Engineering Organization

NASA Technical Reports Server (NTRS)

Suggs, Robert M.

2003-01-01

MSFC's Space Environments Team performs engineering support for a number of NASA spaceflight projects by defining the space environment, developing design requirements, supporting the design process, and supporting operations. Examples of this type of support are given including meteoroid environment work for the Jovian Icy Moon Orbiter mission, ionizing radiation support for the Chandra X-Ray Observatory, and astronomicaVgeophysica1 observation planning for International Space Station.

Engineering Decisions Under Risk-Averseness

DTIC Science & Technology

2014-12-19

ENGINEERING DECISIONS UNDER RISK-AVERSENESS∗ R. Tyrrell Rockafellar Johannes O. Royset Department of Mathematics Operations Research Department...based upon work supported in part by the U. S. Air Force Office of Scientific Research under grants FA9550-11-1-0206 and F1ATAO1194GOO1. 1 Report...S) AND ADDRESS(ES) Naval Postgraduate School,Operations Research Department,Monterey,CA,93943 8. PERFORMING ORGANIZATION REPORT NUMBER 9

Development of Systems Engineering Maturity Models and Management Tools

DTIC Science & Technology

2011-01-21

Ph.D., Senior Personnel, Stevens Institute of Technology Abhi Deshmukh, Ph.D., Senior Personnel, Texas A&M University Matin Sarfaraz, Research ...WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Stevens Institute of Technology,Systems Engineering Research Center (SERC),1...tools (MPT) for effectively and efficiently addressing these challenges are likewise being challenged. The goal of this research was to develop a

What is Microsoft EMET and Why Should I Care?

DTIC Science & Technology

2014-10-22

Headquarters Services , Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302. Respondents should...William 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Software Engineering Institute...with Carnegie Mellon University for the operation of the Software Engineering Institute, a federally funded research and development center sponsored by

Steam automobile analysis

NASA Technical Reports Server (NTRS)

Peoples, J. A.

1975-01-01

Report includes many charts that present graphically the effects of design parameters on performance. Equations and data are given which can assist designer in selecting among such factors as working medium, horsepower, and engine components.

Performance Test on Compression Ignition Engine by Blending Ethanol and Waste Plastic Pyrolysis Oil with Cetane Additive

NASA Astrophysics Data System (ADS)

Padmanabhan, S.; Ganesan, S.; Jeswin Arputhabalan, J.; Chithrala, Varun; Ganesh Bairavan, P.

2017-05-01

The demand for diesel fuel is higher than that of petrol throughout the world hence seeking alternative to mineral diesel is a natural choice. Alternative fuels should be easily available at lower cost, environment friendly and fulfill energy needs without modifying engine’s operational parameters. Waste to energy is the trend in the selection of alternate fuels. In this work, Waste Plastic Pyrolysis oil (WPPO), Ethanol, Diesel blend with Cetane additive has been attempted as an alternative fuel. A Twin cylinder, Direct Injection engine was used to assess the engine performance and emission characteristics of waste plastic pyrolysis oil with cetane additive. Experimental results of blended plastic fuel and diesel fuel were compared.

Review of homogeneous charge compression ignition (HCCI) combustion engines and exhaust gas recirculation (EGR) effects on HCCI

NASA Astrophysics Data System (ADS)

Akma Tuan Kamaruddin, Tengku Nordayana; Wahid, Mazlan Abdul; Sies, Mohsin Mohd

2012-06-01

This paper describes the development in ICE which leads to the new advanced combustion mode named Homogeneous Charge Compression Ignition (HCCI). It explains regarding the theory and working principle of HCCI plus the difference of the process in gasoline and diesel fuelled engines. Many of pioneer and recent research works are discussed to get the current state of art about HCCI. It gives a better indication on the potential of this method in improving the fuel efficiency and emission produced by the vehicles' engine. Apart from the advantages, the challenges and future trend of this technology are also included. HCCI is applying few types of control strategy in producing the optimum performance. This paper looks into Exhaust Gas Recirculation (EGR) as one of the control strategies.

Bridging the Performance Gap with Ergonomics: A Case Study

ERIC Educational Resources Information Center

Rethaber, James D.

2011-01-01

Faced with increased incidences of work-related strain and sprain injuries and OSHA-recordable injuries, the organization in this case study details how it resolved these performance-related issues. This case study also demonstrates the effectiveness of Thomas Gilbert's (1978) Behavior Engineering Model as a tool for analyzing, defining, and…

Fuels Performance | Transportation Research | NREL

Science.gov Websites

. Video Promotes Safe CNG Tank Decommissioning Practices A video on CNG fuel tank defueling instruct transit agencies and others about safe CNG tank end-of-life practices. The video was previewed at Biodiesel Performance in Modern Engines NREL is working cooperatively with the National Biodiesel Board on

Capturing Your Sound: A Guide to Live Recording

ERIC Educational Resources Information Center

Clukey, Tim

2006-01-01

Public performances highlight months of work, but because most school groups cannot afford to hire professional recording engineers, these events are rarely suitably preserved. With small investments of time and equipment, music teachers can create an enduring recording of these fleeting performances. Many of today's digital recording tools are…

Unsteady Probabilistic Analysis of a Gas Turbine System

NASA Technical Reports Server (NTRS)

Brown, Marilyn

2003-01-01

In this work, we have considered an annular cascade configuration subjected to unsteady inflow conditions. The unsteady response calculation has been implemented into the time marching CFD code, MSUTURBO. The computed steady state results for the pressure distribution demonstrated good agreement with experimental data. We have computed results for the amplitudes of the unsteady pressure over the blade surfaces. With the increase in gas turbine engine structural complexity and performance over the past 50 years, structural engineers have created an array of safety nets to ensure against component failures in turbine engines. In order to reduce what is now considered to be excessive conservatism and yet maintain the same adequate margins of safety, there is a pressing need to explore methods of incorporating probabilistic design procedures into engine development. Probabilistic methods combine and prioritize the statistical distributions of each design variable, generate an interactive distribution and offer the designer a quantified relationship between robustness, endurance and performance. The designer can therefore iterate between weight reduction, life increase, engine size reduction, speed increase etc.

Managing Highway Maintenance: Budget Preparation, Unit 9, Level 3.

ERIC Educational Resources Information Center

Federal Highway Administration (DOT), Washington, DC. Offices of Research and Development.

Part of the series "Managing Highway Maintenance," the unit describes the essential steps in developing a maintenance budget, or performance budget, based on the work to be done. It is designed for field engineers and supervisors who assist department officials in preparing work programs and budgets. The format is a programed,…

Social Work Literature Searching: Current Issues with Databases and Online Search Engines

ERIC Educational Resources Information Center

McGinn, Tony; Taylor, Brian; McColgan, Mary; McQuilkan, Janice

2016-01-01

Objectives: To compare the performance of a range of search facilities; and to illustrate the execution of a comprehensive literature search for qualitative evidence in social work. Context: Developments in literature search methods and comparisons of search facilities help facilitate access to the best available evidence for social workers.…

76 FR 17183 - Aviation Rulemaking Advisory Committee; Transport Airplane and Engine Issues-New Task

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-28

... Harmonization Working Group, to assist in analysis of this task. Recent research shows that regardless of... recommend performance-based standards that allows manufacturers the flexibility to design airplanes to meet... level of safety commensurate with part 25. The working group should consider the following areas of the...

Army Corps of Engineers: Cost Increases in Flood Control Projects and Improving Communication with Nonfederal Sponsors

DTIC Science & Technology

2013-12-01

such poor condition that it had to have major rehabilitation work performed. Work to fix the deteriorated tunnel cost $10 million more than had...originally been estimated.19 Corps officials on the Little Calumet project said during construction they encountered a former landfill along one portion

43 CFR 3836.14 - What other requirements must geological, geochemical, or geophysical surveys meet to qualify as...

Code of Federal Regulations, 2011 CFR

2011-10-01

... qualified expert is a geologist or mining engineer qualified by education and experience to conduct... INTERIOR MINERALS MANAGEMENT (3000) ANNUAL ASSESSMENT WORK REQUIREMENTS FOR MINING CLAIMS Performing... analyzing the data. (c) You may not count these surveys as assessment work for more than 2 consecutive years...

43 CFR 3836.14 - What other requirements must geological, geochemical, or geophysical surveys meet to qualify as...

Code of Federal Regulations, 2014 CFR

2014-10-01

... qualified expert is a geologist or mining engineer qualified by education and experience to conduct... INTERIOR MINERALS MANAGEMENT (3000) ANNUAL ASSESSMENT WORK REQUIREMENTS FOR MINING CLAIMS Performing... analyzing the data. (c) You may not count these surveys as assessment work for more than 2 consecutive years...

43 CFR 3836.14 - What other requirements must geological, geochemical, or geophysical surveys meet to qualify as...

Code of Federal Regulations, 2013 CFR

2013-10-01

... qualified expert is a geologist or mining engineer qualified by education and experience to conduct... INTERIOR MINERALS MANAGEMENT (3000) ANNUAL ASSESSMENT WORK REQUIREMENTS FOR MINING CLAIMS Performing... analyzing the data. (c) You may not count these surveys as assessment work for more than 2 consecutive years...

43 CFR 3836.14 - What other requirements must geological, geochemical, or geophysical surveys meet to qualify as...

Code of Federal Regulations, 2012 CFR

2012-10-01

... qualified expert is a geologist or mining engineer qualified by education and experience to conduct... INTERIOR MINERALS MANAGEMENT (3000) ANNUAL ASSESSMENT WORK REQUIREMENTS FOR MINING CLAIMS Performing... analyzing the data. (c) You may not count these surveys as assessment work for more than 2 consecutive years...

JPRS Report, Science & Technology, USSR: Engineering & Equipment

DTIC Science & Technology

1987-08-10

the operating processes take place in diametrically opposed working chambers and the pressure forces are mutually compensated. And finally, the ... developed in a new qualitative basis. The State Acceptance Service, as one of the most important links of all work , will thus place much in its...committee, is summarized at length. Assessing the industry’s recent performance, Semenov praised work in robotics at the

Propulsion Risk Reduction Activities for Non-Toxic Cryogenic Propulsion

NASA Technical Reports Server (NTRS)

Smith, Timothy D.; Klem, Mark D.; Fisher, Kenneth

2010-01-01

The Propulsion and Cryogenics Advanced Development (PCAD) Project s primary objective is to develop propulsion system technologies for non-toxic or "green" propellants. The PCAD project focuses on the development of non-toxic propulsion technologies needed to provide necessary data and relevant experience to support informed decisions on implementation of non-toxic propellants for space missions. Implementation of non-toxic propellants in high performance propulsion systems offers NASA an opportunity to consider other options than current hypergolic propellants. The PCAD Project is emphasizing technology efforts in reaction control system (RCS) thruster designs, ascent main engines (AME), and descent main engines (DME). PCAD has a series of tasks and contracts to conduct risk reduction and/or retirement activities to demonstrate that non-toxic cryogenic propellants can be a feasible option for space missions. Work has focused on 1) reducing the risk of liquid oxygen/liquid methane ignition, demonstrating the key enabling technologies, and validating performance levels for reaction control engines for use on descent and ascent stages; 2) demonstrating the key enabling technologies and validating performance levels for liquid oxygen/liquid methane ascent engines; and 3) demonstrating the key enabling technologies and validating performance levels for deep throttling liquid oxygen/liquid hydrogen descent engines. The progress of these risk reduction and/or retirement activities will be presented.

Propulsion Risk Reduction Activities for Nontoxic Cryogenic Propulsion

NASA Technical Reports Server (NTRS)

Smith, Timothy D.; Klem, Mark D.; Fisher, Kenneth L.

2010-01-01

The Propulsion and Cryogenics Advanced Development (PCAD) Project s primary objective is to develop propulsion system technologies for nontoxic or "green" propellants. The PCAD project focuses on the development of nontoxic propulsion technologies needed to provide necessary data and relevant experience to support informed decisions on implementation of nontoxic propellants for space missions. Implementation of nontoxic propellants in high performance propulsion systems offers NASA an opportunity to consider other options than current hypergolic propellants. The PCAD Project is emphasizing technology efforts in reaction control system (RCS) thruster designs, ascent main engines (AME), and descent main engines (DME). PCAD has a series of tasks and contracts to conduct risk reduction and/or retirement activities to demonstrate that nontoxic cryogenic propellants can be a feasible option for space missions. Work has focused on 1) reducing the risk of liquid oxygen/liquid methane ignition, demonstrating the key enabling technologies, and validating performance levels for reaction control engines for use on descent and ascent stages; 2) demonstrating the key enabling technologies and validating performance levels for liquid oxygen/liquid methane ascent engines; and 3) demonstrating the key enabling technologies and validating performance levels for deep throttling liquid oxygen/liquid hydrogen descent engines. The progress of these risk reduction and/or retirement activities will be presented.

Would Consolidation of Army Software Engineering Organizations Help to Control Software Costs for Current and Future Systems

DTIC Science & Technology

2015-04-16

Specific to Work and Organization .................................................................... 32 Summary of Questions Specific to Work and...Limitations include assumptions that the work identified in the software center’s 6 mission and functions manual (10-1; CECOM, 2011) as well as in public...that produced RDECOM. The focus was on the movement of positions based on the position job series, not on the work that was actually being performed

Marquardt's Mach 4.5 Supercharged Ejector Ramjet (SERJ) High-Performance Aircraft Engine Project: Unfulfilled Aspirations Ca.1970

NASA Technical Reports Server (NTRS)

Escher, William J. D.; Roddy, Jordan E.; Hyde, Eric H.

2000-01-01

The Supercharged Ejector Ramjet (SERJ) engine developments of the 1960s, as pursued by The Marquardt Corporation and its associated industry team members, are described. In just three years, engineering work on this combined-cycle powerplant type evolved, from its initial NASA-sponsored reusable space transportation system study status, into a U.S. Air Force/Navy-supported exploratory development program as a candidate 4.5 high-performance military aircraft engine. Bridging a productive transition from the spaceflight to the aviation arena, this case history supports the expectation that fully-integrated airbreathing/rocket propulsion systems hold high promise toward meeting the demanding propulsion requirements of tomorrow's aircraft-like Spaceliner class transportation systems. Lessons to be learned from this "SERJ Story" are offered for consideration by today's advanced space transportation and combined-cycle propulsion researchers and forward-planning communities.

Propane-Fueled Jet Engine

NASA Astrophysics Data System (ADS)

Farwell, D. A.; Svenson, A. J.; Ramsier, R. D.

2001-04-01

We present our recent efforts to design, construct, and test a gas turbine, or jet, engine. Our design utilizes a turbocharger and ignition system from an automobile, and a flame tube/reaction chamber unit fabricated by hand from stainless steel. Once the engine is running, it is completely self-sustaining as long as there is a fuel supply, which in our case is propane. Air is forced into the intake where it is compressed and then injected into the combustion chamber where it is mixed with propane. The spark plugs ignite the air-propane mixture which burns to produce thrust at the exhaust. We have performed operational tests under different environmental conditions and with several turbochargers. We are currently working on adding a lubrication system to the engine, and will discuss our plan to experiment with the reaction chamber and flame tube design in an effort to improve performance and efficiency. *Corresponding author: rex@uakron.edu

The NASA hypersonic research engine program

NASA Technical Reports Server (NTRS)

Rubert, Kennedy F.; Lopez, Henry J.

1992-01-01

An overview is provided of the NASA Hypersonic Research Engine Program. The engine concept is described which was evolved, and the accomplishments of the program are summarized. The program was undertaken as an in-depth program of hypersonic airbreathing propulsion research to provide essential inputs to future prototype engine development and decision making. An airbreathing liquid hydrogen fueled research oriented scramjet was to be developed to certain performance goals. The work was many faceted, required aerodynamic design evaluation, structures development, and development of flight systems such as the fuel and control system, but the main objective was the study of the internal aerothermodynamics of the propulsion system.

Design and optimization of the micro-engine turbine rotor manufacturing using the rapid prototyping technology

NASA Astrophysics Data System (ADS)

Vdovin, R. A.; Smelov, V. G.

2017-02-01

This work describes the experience in manufacturing the turbine rotor for the micro-engine. It demonstrates the design principles for the complex investment casting process combining the use of the ProCast software and the rapid prototyping techniques. At the virtual modelling stage, in addition to optimized process parameters, the casting structure was improved to obtain the defect-free section. The real production stage allowed demonstrating the performance and fitness of rapid prototyping techniques for the manufacture of geometrically-complex engine-building parts.

Value engineering on the designed operator work tools for brick and rings wells production

NASA Astrophysics Data System (ADS)

Ayu Bidiawati J., R.; Muchtiar, Yesmizarti; Wariza, Ragil Okta

2017-06-01

Operator working tools in making brick and ring wells were designed and made, and the value engineering was calculated to identify and develop the function of these tools in obtaining the balance between cost, reliability and appearance. This study focused on the value of functional components of the tools and attempted to increase the difference between the costs incurred by the generated values. The purpose of this study was to determine the alternatives of tools design and to determine the performance of each alternative. The technique was developed using FAST method that consisted of five stages: information, creative, analytical, development and presentation stage. The results of the analysis concluded that the designed tools have higher value and better function description. There were four alternative draft improvements for operator working tools. The best alternative was determined based on the rank by using matrix evaluation. Best performance was obtained by the alternative II, amounting to 98.92 with a value of 0.77.

LOW-ENGINE-FRICTION TECHNOLOGY FOR ADVANCED NATURAL-GAS RECIPROCATING ENGINES

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

Victor W. Wong; Tian Tian; Grant Smedley

2003-08-28

This program aims at improving the efficiency of advanced natural-gas reciprocating engines (ANGRE) by reducing piston/ring assembly friction without major adverse effects on engine performance, such as increased oil consumption and emissions. A detailed set of piston/ring dynamic and friction models have been developed and applied that illustrated the fundamental relationships between design parameters and friction losses. Various low-friction strategies and concepts have been explored, and engine experiments will validate these concepts. An iterative process of experimentation, simulation and analysis, will be followed with the goal of demonstrating a complete optimized low-friction engine system. As planned, MIT has developed guidelinesmore » for an initial set of low-friction piston-ring-pack designs. Current recommendations focus on subtle top-piston-ring and oil-control-ring characteristics. A full-scale Waukesha F18 engine has been installed at Colorado State University and testing of the baseline configuration is in progress. Components for the first design iteration are being procured. Subsequent work includes examining the friction and engine performance data and extending the analyses to other areas to evaluate opportunities for further friction improvement and the impact on oil consumption/emission and wear, towards demonstrating an optimized reduced-friction engine system.« less

Digital Model-Based Engineering: Expectations, Prerequisites, and Challenges of Infusion

NASA Technical Reports Server (NTRS)

Hale, J. P.; Zimmerman, P.; Kukkala, G.; Guerrero, J.; Kobryn, P.; Puchek, B.; Bisconti, M.; Baldwin, C.; Mulpuri, M.

2017-01-01

Digital model-based engineering (DMbE) is the use of digital artifacts, digital environments, and digital tools in the performance of engineering functions. DMbE is intended to allow an organization to progress from documentation-based engineering methods to digital methods that may provide greater flexibility, agility, and efficiency. The term 'DMbE' was developed as part of an effort by the Model-Based Systems Engineering (MBSE) Infusion Task team to identify what government organizations might expect in the course of moving to or infusing MBSE into their organizations. The Task team was established by the Interagency Working Group on Engineering Complex Systems, an informal collaboration among government systems engineering organizations. This Technical Memorandum (TM) discusses the work of the MBSE Infusion Task team to date. The Task team identified prerequisites, expectations, initial challenges, and recommendations for areas of study to pursue, as well as examples of efforts already in progress. The team identified the following five expectations associated with DMbE infusion, discussed further in this TM: (1) Informed decision making through increased transparency, and greater insight. (2) Enhanced communication. (3) Increased understanding for greater flexibility/adaptability in design. (4) Increased confidence that the capability will perform as expected. (5) Increased efficiency. The team identified the following seven challenges an organization might encounter when looking to infuse DMbE: (1) Assessing value added to the organization. Not all DMbE practices will be applicable to every situation in every organization, and not all implementations will have positive results. (2) Overcoming organizational and cultural hurdles. (3) Adopting contractual practices and technical data management. (4) Redefining configuration management. The DMbE environment changes the range of configuration information to be managed to include performance and design models, database objects, as well as more traditional book-form objects and formats. (5) Developing information technology (IT) infrastructure. Approaches to implementing critical, enabling IT infrastructure capabilities must be flexible, reconfigurable, and updatable. (6) Ensuring security of the single source of truth (7) Potential overreliance on quantitative data over qualitative data. Executable/ computational models and simulations generally incorporate and generate quantitative vice qualitative data. The Task team also developed several recommendations for government, academia, and industry, as discussed in this TM. The Task team recommends continuing beyond this initial work to further develop the means of implementing DMbE and to look for opportunities to collaborate and share best practices.

Steady-State Cycle Deck Launcher Developed for Numerical Propulsion System Simulation

NASA Technical Reports Server (NTRS)

VanDrei, Donald E.

1997-01-01

One of the objectives of NASA's High Performance Computing and Communications Program's (HPCCP) Numerical Propulsion System Simulation (NPSS) is to reduce the time and cost of generating aerothermal numerical representations of engines, called customer decks. These customer decks, which are delivered to airframe companies by various U.S. engine companies, numerically characterize an engine's performance as defined by the particular U.S. airframe manufacturer. Until recently, all numerical models were provided with a Fortran-compatible interface in compliance with the Society of Automotive Engineers (SAE) document AS681F, and data communication was performed via a standard, labeled common structure in compliance with AS681F. Recently, the SAE committee began to develop a new standard: AS681G. AS681G addresses multiple language requirements for customer decks along with alternative data communication techniques. Along with the SAE committee, the NPSS Steady-State Cycle Deck project team developed a standard Application Program Interface (API) supported by a graphical user interface. This work will result in Aerospace Recommended Practice 4868 (ARP4868). The Steady-State Cycle Deck work was validated against the Energy Efficient Engine customer deck, which is publicly available. The Energy Efficient Engine wrapper was used not only to validate ARP4868 but also to demonstrate how to wrap an existing customer deck. The graphical user interface for the Steady-State Cycle Deck facilitates the use of the new standard and makes it easier to design and analyze a customer deck. This software was developed following I. Jacobson's Object-Oriented Design methodology and is implemented in C++. The AS681G standard will establish a common generic interface for U.S. engine companies and airframe manufacturers. This will lead to more accurate cycle models, quicker model generation, and faster validation leading to specifications. The standard will facilitate cooperative work between industry and NASA. The NPSS Steady-State Cycle Deck team released a batch version of the Steady-State Cycle Deck in March 1996. Version 1.1 was released in June 1996. During fiscal 1997, NPSS accepted enhancements and modifications to the Steady-State Cycle Deck launcher. Consistent with NPSS' commercialization plan, these modifications will be done by a third party that can provide long-term software support.

Engineering with uncertainty: monitoring air bag performance.

PubMed

Wetmore, Jameson M

2008-06-01

Modern engineering is complicated by an enormous number of uncertainties. Engineers know a great deal about the material world and how it works. But due to the inherent limits of testing and the complexities of the world outside the lab, engineers will never be able to fully predict how their creations will behave. One way the uncertainties of engineering can be dealt with is by actively monitoring technologies once they have left the development and production stage. This article uses an episode in the history of automobile air bags as an example of engineers who had the foresight and initiative to carefully track the technology on the road to discover problems as early as possible. Not only can monitoring help engineers identify problems that surface in the field, it can also assist them in their efforts to mobilize resources to resolve problem.

Solar Stirling power generation - Systems analysis and preliminary tests

NASA Technical Reports Server (NTRS)

Selcuk, M. K.; Wu, Y.-C.; Moynihan, P. I.; Day, F. D., III

1977-01-01

The feasibility of an electric power generation system utilizing a sun-tracking parabolic concentrator and a Stirling engine/linear alternator is being evaluated. Performance predictions and cost analysis of a proposed large distributed system are discussed. Design details and preliminary test results are presented for a 9.5 ft diameter parabolic dish at the Jet Propulsion Laboratory (Caltech) Table Mountain Test Facility. Low temperature calorimetric measurements were conducted to evaluate the concentrator performance, and a helium flow system is being used to test the solar receiver at anticipated working fluid temperatures (up to 650 or 1200 C) to evaluate the receiver thermal performance. The receiver body is designed to adapt to a free-piston Stirling engine which powers a linear alternator assembly for direct electric power generation. During the next phase of the program, experiments with an engine and receiver integrated into the concentrator assembly are planned.

Irreversible and endoreversible behaviors of the LD-model for heat devices: the role of the time constraints and symmetries on the performance at maximum χ figure of merit

NASA Astrophysics Data System (ADS)

Gonzalez-Ayala, Julian; Calvo Hernández, A.; Roco, J. M. M.

2016-07-01

The main unified energetic properties of low dissipation heat engines and refrigerator engines allow for both endoreversible or irreversible configurations. This is accomplished by means of the constraints imposed on the characteristic global operation time or the contact times between the working system with the external heat baths and modulated by the dissipation symmetries. A suited unified figure of merit (which becomes power output for heat engines) is analyzed and the influence of the symmetries on the optimum performance discussed. The obtained results, independent on any heat transfer law, are faced with those obtained from Carnot-like heat models where specific heat transfer laws are needed. Thus, it is shown that only the inverse phenomenological law, often used in linear irreversible thermodynamics, correctly reproduces all optimized values for both the efficiency and coefficient of performance values.

Performance analysis of quantum Diesel heat engines with a two-level atom as working substance

NASA Astrophysics Data System (ADS)

Huang, X. L.; Shang, Y. F.; Guo, D. Y.; Yu, Qian; Sun, Qi

2017-07-01

A quantum Diesel cycle, which consists of one quantum isobaric process, one quantum isochoric process and two quantum adiabatic processes, is established with a two-level atom as working substance. The parameter R in this model is defined as the ratio of the time in quantum isochoric process to the timescale for the potential width movement. The positive work condition, power output and efficiency are obtained, and the optimal performance is analyzed with different R. The effects of dissipation, the mixed state in the cycle and the results of other working substances are also discussed at the end of this analysis.

Views of a Cal/OSHA Inspector.

PubMed

Oudiz, Jack

2009-01-01

Retiring CAL/OSHA Industrial Hygienist and Senior Safety Engineer Jack Oudiz offers his thoughts in the nature of a voluntary "exit interview" on his years working for the agency and its performance in its mission.

Experimental investigation on the availability, performance, combustion and emission distinctiveness of bael oil/ diesel/ diethyl ether blends powered in a variable compression ratio diesel engine

NASA Astrophysics Data System (ADS)

Krishnamoorthi, M.; Malayalamurthi, R.

2018-02-01

The present work aims at experimental investigation on the combined effect of injection timing (IT) and injection pressure (IP) on the performance and emissions characteristics, and exergy analysis of a compression-ignition (CI) engine powered with bael oil blends. The tests were conducted using ternary blends of bael oil, diethyl ether (DEE) and neat diesel (D) at various engine loads at a constant engine speed (1500 rpm). With B2 (60%D + 30%bael oil+10%DEE) fuel, the brake thermal efficiency (BTE) of the engine is augmented by 3.5%, reduction of 4.7% of oxides of nitrogen (NOx) emission has been observed at 100% engine load with 250 bar IP. B2 fuel exhibits 7% lower scale of HC emissions compared to that of diesel fuel at 100% engine load in 23 °bTDC IT. The increment in both cooling water and exhaust gas availabilities lead to increasing exergy efficiency with increasing load. The exergy efficiency of about 62.17% has been recorded by B2 fuel at an injection pressure of 230 IP bar with 100% load. On the whole, B2 fuel displays the best performance and combustion characteristics. It also exhibits better characteristics of emissions level in terms of lower HC, smoke opacity and NOx.

Stirling Laboratory Research Engine: Preprototype configuration report

NASA Technical Reports Server (NTRS)

Hoehn, F. W.

1982-01-01

The concept of a simple Stirling research engine that could be used by industrial, university, and government laboratories was studied. The conceptual and final designs, hardware fabrication and the experimental validation of a preprototype stirling laboratory research engine (SLRE) were completed. Also completed was a task to identify the potential markets for research engines of this type. An analytical effort was conducted to provide a stirling cycle computer model. The versatile engine is a horizontally opposed, two piston, single acting stirling engine with a split crankshaft drive mechanism; special instrumentation is installed at all component interfaces. Results of a thermodynamic energy balance for the system are reported. Also included are the engine performance results obtained over a range of speeds, working pressures, phase angles and gas temperatures. The potential for a stirling research engine to support the laboratory requirements of educators and researchers was demonstrated.

Three-dimensional anthropometric techniques applied to the fabrication of burn masks and the quantification of wound healing

NASA Astrophysics Data System (ADS)

Whitestone, Jennifer J.; Geisen, Glen R.; McQuiston, Barbara K.

1997-03-01

Anthropometric surveys conducted by the military provide comprehensive human body measurement data that are human interface requirements for successful mission performance of weapon systems, including cockpits, protective equipment, and clothing. The application of human body dimensions to model humans and human-machine performance begins with engineering anthropometry. There are two critical elements to engineering anthropometry: data acquisition and data analysis. First, the human body is captured dimensionally with either traditional anthropometric tools, such as calipers and tape measures, or with advanced image acquisition systems, such as a laser scanner. Next, numerous statistical analysis tools, such as multivariate modeling and feature envelopes, are used to effectively transition these data for design and evaluation of equipment and work environments. Recently, Air Force technology transfer allowed researchers at the Computerized Anthropometric Research and Design (CARD) Laboratory at Wright-Patterson Air Force Base to work with the Dayton, Ohio area medical community in assessing the rate of wound healing and improving the fit of total contract burn masks. This paper describes the successful application of CARD Lab engineering anthropometry to two medically oriented human interface problems.

Engineering-Scale Demonstration of DuraLith and Ceramicrete Waste Forms

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

Josephson, Gary B.; Westsik, Joseph H.; Pires, Richard P.

2011-09-23

To support the selection of a waste form for the liquid secondary wastes from the Hanford Waste Immobilization and Treatment Plant, Washington River Protection Solutions (WRPS) has initiated secondary waste form testing on four candidate waste forms. Two of the candidate waste forms have not been developed to scale as the more mature waste forms. This work describes engineering-scale demonstrations conducted on Ceramicrete and DuraLith candidate waste forms. Both candidate waste forms were successfully demonstrated at an engineering scale. A preliminary conceptual design could be prepared for full-scale production of the candidate waste forms. However, both waste forms are stillmore » too immature to support a detailed design. Formulations for each candidate waste form need to be developed so that the material has a longer working time after mixing the liquid and solid constituents together. Formulations optimized based on previous lab studies did not have sufficient working time to support large-scale testing. The engineering-scale testing was successfully completed using modified formulations. Further lab development and parametric studies are needed to optimize formulations with adequate working time and assess the effects of changes in raw materials and process parameters on the final product performance. Studies on effects of mixing intensity on the initial set time of the waste forms are also needed.« less

Application of the Tool for Turbine Engine Closed-loop Transient Analysis (TTECTrA) for Dynamic Systems Analysis

NASA Technical Reports Server (NTRS)

Csank, Jeffrey; Zinnecker, Alicia

2014-01-01

Systems analysis involves steady-state simulations of combined components to evaluate the steady-state performance, weight, and cost of a system; dynamic considerations are not included until later in the design process. The Dynamic Systems Analysis task, under NASAs Fixed Wing project, is developing the capability for assessing dynamic issues at earlier stages during systems analysis. To provide this capability the Tool for Turbine Engine Closed-loop Transient Analysis (TTECTrA) has been developed to design a single flight condition controller (defined as altitude and Mach number) and, ultimately, provide an estimate of the closed-loop performance of the engine model. This tool has been integrated with the Commercial Modular Aero-Propulsion System Simulation 40,000(CMAPSS40k) engine model to demonstrate the additional information TTECTrA makes available for dynamic systems analysis. This dynamic data can be used to evaluate the trade-off between performance and safety, which could not be done with steady-state systems analysis data. TTECTrA has been designed to integrate with any turbine engine model that is compatible with the MATLABSimulink (The MathWorks, Inc.) environment.

Application of the Tool for Turbine Engine Closed-loop Transient Analysis (TTECTrA) for Dynamic Systems Analysis

NASA Technical Reports Server (NTRS)

Csank, Jeffrey Thomas; Zinnecker, Alicia Mae

2014-01-01

Systems analysis involves steady-state simulations of combined components to evaluate the steady-state performance, weight, and cost of a system; dynamic considerations are not included until later in the design process. The Dynamic Systems Analysis task, under NASAs Fixed Wing project, is developing the capability for assessing dynamic issues at earlier stages during systems analysis. To provide this capability the Tool for Turbine Engine Closed-loop Transient Analysis (TTECTrA) has been developed to design a single flight condition controller (defined as altitude and Mach number) and, ultimately, provide an estimate of the closed-loop performance of the engine model. This tool has been integrated with the Commercial Modular Aero-Propulsion System Simulation 40,000 (CMAPSS 40k) engine model to demonstrate the additional information TTECTrA makes available for dynamic systems analysis. This dynamic data can be used to evaluate the trade-off between performance and safety, which could not be done with steady-state systems analysis data. TTECTrA has been designed to integrate with any turbine engine model that is compatible with the MATLAB Simulink (The MathWorks, Inc.) environment.

Comparative investigation of novel hetero gate dielectric and drain engineered charge plasma TFET for improved DC and RF performance

NASA Astrophysics Data System (ADS)

Yadav, Dharmendra Singh; Verma, Abhishek; Sharma, Dheeraj; Tirkey, Sukeshni; Raad, Bhagwan Ram

2017-11-01

Tunnel-field-effect-transistor (TFET) has emerged as one of the most prominent devices to replace conventional MOSFET due to its ability to provide sub-threshold slope below 60 mV/decade (SS ≤ 60 mV/decade) and low leakage current. Despite this, TFETs suffer from ambipolar behavior, lower ON-state current, and poor RF performance. To address these issues, we have introduced drain and gate work function engineering with hetero gate dielectric for the first time in charge plasma based doping-less TFET (DL TFET). In this, the usage of dual work functionality over the drain region significantly reduces the ambipolar behavior of the device by varying the energy barrier at drain/channel interface. Whereas, the presence of dual work function at the gate terminal increases the ON-state current (ION). The combined effect of dual work function at the gate and drain electrode results in the increment of ON-state current (ION) and decrement of ambipolar conduction (Iambi) respectively. Furthermore, the incorporation of hetero gate dielectric along with dual work functionality at the drain and gate electrode provides an overall improvement in the performance of the device in terms of reduction in ambipolarity, threshold voltage and sub-threshold slope along with improved ON-state current and high frequency figures of merit.

NASA's Space Launch System: Progress Report

NASA Technical Reports Server (NTRS)

Cook, Jerry; Lyles, Garry

2017-01-01

NASA and its commercial industry team achieved significant progress in 2016 in manufacturing and testing of the Block 1 vehicle for the first launch of the Space Launch System (SLS). Test and flight article hardware for the liquid hydrogen fuel tank as well as the engine section for the core stage were completed at Michoud Assembly Facility (MAF) in New Orleans. Test stands neared completion at Marshall Space Flight Center for the propellant tanks, engine section, intertank and payload section. Stennis Space Center completed major structural renovations on the B2 test stand, where the core stage "green run" test program will be conducted. The SLS team completed a hotfire test series at Stennis to successfully demonstrate the ability of the RS-25 engine to operate under SLS environments and performance conditions. The team also test fired the second qualification five-segment solid rocket motor and cast the first six motor segments for the first SLS mission. The Interim Cryogenic Propulsion Stage (ICPS) test article was delivered to Marshall for structural tests, and work is nearly finished on the flight stage. Flight software testing completed at Marshall included power quality and command and data handling. In 2017, that work continues. SLS completed Preliminary Design Review (PDR) on the Exploration Upper Stage (EUS), a powerful, human-rated spacecraft that will propel explorers to cis-lunar space. In 2017, hardware will continue to be integrated at MAF for core stage structural test articles and the first two operational flights. RS-25 hotfire testing will continue to explore engine performance, as well as test flight-like software and four new Engine Controller Units (ECUs) for the first mission. Production of development components for a more affordable RS-25 design is underway. Core stage structural test articles have begun arriving at Marshall. While engineering challenges typical of a new development are possible, SLS is working toward launch readiness in late 2018. This paper will discuss these and other technical and programmatic successes and challenges over the past year and provide a preview of work ahead before first flight

Evaluating the Performance Improvement Preferences of Disability Service Managers: An Exploratory Study Using Gilbert's Behavior Engineering Model

ERIC Educational Resources Information Center

Wooderson, John R.; Cuskelly, Monica; Meyer, Kim A.

2017-01-01

Background: Front-line managers play an important role in managing the performance of staff working in services for people with intellectual disability, but little is known about the practices they prefer to use to improve staff performance and whether these align with what research has shown to be effective. Method: This study comprised two…

NASA/DERA Collaborative Program

NASA Technical Reports Server (NTRS)

Whitefield, Phillip D.; Hagen, Donald E.; Wormhoudt, Jody C.; Miake-Lye, Richard C.; Brundish, Kevin; Wilson, Christopher W.; Wey, Chowen (Technical Monitor)

2002-01-01

This report is an interim report. The work reported are the results from the combustor testing, the first phase of testing in the DERA/NASA collaborative program. A program of work was developed by DERA and NASA utilizing specialist facilities within the UK, and specialist measurement techniques developed within the U.S. Under a Memorandum of Understanding (MoU) between the UK and U.S. governments, the joint UK/U.S. funded program commenced. The objective of the program was to make combustor and engine exit plane emissions measurements, including particulate and sulphur measurements, for kerosene fuels with different sulphur levels. The combustor test program was performed in August/September 2000. Although probe issues complicated the test program, a consistent set of data, including CO, NO(x), NO, NO2, CO2, O2, smoke number, particulate number density and size distribution, SO2, SO3 and HONO were collected at the exit plane of the DERA TRACE engine combustor. A second probe was utilized to measure spatial location of CO, NO(x), NO, NO2 and CO2 concentrations. Data are therefore available for development of aerosol, particulate and aerosol precursor chemistry sub-models for inclusion into CFD. Inlet boundary conditions have been derived at the exit of the combustion system for the modelling of the DERA TRACE engine. The second phase of the program is to perform identical measurements at the engine exit, to allow a full data set to be available. This will be performed in July 2001 at the Glenn test facility, DERA Pyestock.

USSR and Eastern Europe Scientific Abstracts, Electronics and Electrical Engineering, Number 24.

DTIC Science & Technology

1976-11-12

GERMANY DUMMER, Joachim, graduate mathematician, and KLEIN, Richard, graduate engineer, Radio Works Combine State Enterprise, Erfurt DIGITAL FRONT PANEL ...operation, performance, and applications of a digital front panel display instrument was described and illustrated with circuit diagrams, block diagrams...technics, various digital and alphabetic panels , holography, and possibly the screens of cathode-ray tubes. One of the chief merits of "ftiros" is the

Applying the Goal-Question-Indicator-Metric (GQIM) Method to Perform Military Situational Analysis

DTIC Science & Technology

2016-05-11

www.sei.cmu.edu CMU/SEI-2016-TN-003 | SOFTWARE ENGINEERING INSTITUTE | CARNEGIE MELLON UNIVERSITY Distribution Statement A: Approved for Public Release...Distribution is Unlimited Copyright 2016 Carnegie Mellon University This material is based upon work funded and supported by the Department of...Defense under Contract No. FA8721-05-C-0003 with Carnegie Mellon University for the operation of the Software Engineering Institute, a federally

From Relational Interfaces to Assume-Guarantee Contracts

DTIC Science & Technology

2014-03-18

Electrical Engineering and Computer Sciences University of California at Berkeley Technical Report No. UCB/EECS-2014-21 http://www.eecs.berkeley.edu/Pubs...5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) University of California at Berkeley, Electrical Engineering...design,” in EMSOFT’01. Springer, LNCS 2211, 2001. [2] A. Sangiovanni-Vincentelli et al., “Taming Dr. Frankenstein : Contract-Based Design for Cyber

Tradeoffs Between Synchronization, Communication, and Work in Parallel Linear Algebra Computations

DTIC Science & Technology

2014-01-25

Demmel Electrical Engineering and Computer Sciences University of California at Berkeley Technical Report No. UCB/EECS-2014- 8 http...www.eecs.berkeley.edu/Pubs/TechRpts/2014/EECS-2014- 8 .html January 25, 2014 Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the...University of California at Berkeley,Electrical Engineering and Computer Sciences,Berkeley,CA,94720 8 . PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING

A Measure of Effectiveness - Analysis and Application.

DTIC Science & Technology

1981-06-01

PODELL UNCLASSIFIED DCEC-TN-I2-81 NLEEEllllllllllI IIIIIIIIII!I IIIIEIIIIIIII2 4 LEYEV AD A10788 6 TN 2-81 DEFENSE COMMUNICATIONS ENGINEERING CENTER...AUTOR~a)8. CONTRACT OR GRANT NUMBER(&) .OBERT PODELL 9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT PROJECT, TASK AREA 6 WORK UNIT...APPLICATION JUNE 1981 Prepared by: @ Robert Podell Approved for Publication: G.E.LaVE-AN Chief, Systems Engineering Division FOREWORD The Defense

Internal Flow

NASA Astrophysics Data System (ADS)

Greitzer, E. M.; Tan, C. S.; Graf, M. B.

2004-06-01

Focusing on phenomena important in implementing the performance of a broad range of fluid devices, this work describes the behavior of internal flows encountered in propulsion systems, fluid machinery (compressors, turbines, and pumps) and ducts (diffusers, nozzles and combustion chambers). The book equips students and practicing engineers with a range of new analytical tools. These tools offer enhanced interpretation and application of both experimental measurements and the computational procedures that characterize modern fluids engineering.

US Naval Facilities Engineering Service Center Environmental Program on Climate Change

DTIC Science & Technology

2008-09-01

of environmental issues related to climate change . There is a growing recognition that the Navy will need to perform its national security mission in... climate change -related technology work at the Naval Facilities Engineering Service Center (NAVFAC ESC) in Port Hueneme, California. NAVFAC ESC...categorized technologies that can be applied to climate change as mitigation, adaptation, and intervention. An essential element of the Navy’s response to

CrossTalk: The Journal of Defense Software Engineering. Volume 19, Number 12, December 2006

DTIC Science & Technology

2006-12-01

Feature-Oriented Domain Analysis ( FODA ) FODA is a domain analysis and engineer- ing method that focuses on developing reusable assets [9]. By examining...Eliciting Security Requirements This article describes an approach for doing trade-off analysis among requirements elicitation methods. by Dr. Nancy R...high-level requirements are addressed and met in the requirements work products. 3. Unclear requirements Mitigation Perform requirements analysis and

KSC-2011-2678

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Main engine No. 1, which was removed from space shuttle Discovery, is transported from Orbiter Processing Facility-2 to the Space Shuttle Main Engine Processing Facility at NASA's Kennedy Space Center in Florida. The removal was part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

KSC-2011-2677

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Main engine No. 1, which was removed from space shuttle Discovery, is transported from Orbiter Processing Facility-2 to the Space Shuttle Main Engine Processing Facility at NASA's Kennedy Space Center in Florida. The removal was part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

KSC-2011-2679

NASA Image and Video Library

2011-04-01

CAPE CANAVERAL, Fla. - Main engine No. 1, which was removed from space shuttle Discovery, is transported from Orbiter Processing Facility-2 to the Space Shuttle Main Engine Processing Facility at NASA's Kennedy Space Center in Florida. The removal was part of Discovery's transition and retirement processing. Work performed on Discovery is expected to help rocket designers build next-generation spacecraft and prepare the shuttle for future public display. Photo credit: NASA/Jack Pfaller

The performance simulation of single cylinder electric power confined piston engine

NASA Astrophysics Data System (ADS)

Gou, Yanan

2017-04-01

A new type of power plant. i.e, Electric Power Confined Piston Engine, is invented by combining the free piston engine and the crank connecting rod mechanism of the traditional internal combustion engine. Directly using the reciprocating movement of the piston, this new engine converts the heat energy produced by fuel to electrical energy and output it. The paper expounds the working mechanism of ECPE and establishes the kinematics and dynamics equations. Furthermore, by using the analytic method, the ECPE electromagnetic force is solved at load cases. Finally, in the simulation environment of MARLAB, the universal characteristic curve is obtained in the condition of rotational speed n between 1000 r/min and 2400 r/min, throttle opening α between 30% and 100%.

Comparison of measured and calculated forces on the RE-1000 free-piston Stirling engine displacer

NASA Technical Reports Server (NTRS)

Schreiber, Jeffrey G.

1987-01-01

The NASA Lewis Research Center has tested a 1 kW free-piston Stirling engine at the NASA Lewis test facilities. The tests performed over the past several years on the RE-1000 single cylinder engine are known as the sensitivity tests. This report presents an analysis of some of the data published in the sensitivity test report. A basic investigation into the measured forces acting on the unconstrained displacer of the engine is presented. These measured forces are then correlated with the values predicted by the NASA Lewis Stirling engine computer simulation. The results of the investigation are presented in the form of phasor diagrams. Possible future work resulting from this investigation is outlined.

NREL Photovoltaic Program FY 1995 annual report

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

NONE

1996-06-01

This report summarizes the in-house and subcontracted R&D activities from Oct. 1994 through Sept. 1995; their objectives are to conduct basic, applied, and engineering research, manage subcontracted R&D projects, perform research complementary to subcontracted work, develop and maintain state-of-the-art measurement and device capabilities, develop PV manufacturing technology and modules, transfer results to industry, and evolve viable partnerships for PV systems and market development. The research activities are grouped into 5 sections: crystalline Si and advanced devices, thin-film PV, PV manufacturing, PV module and system performance and engineering, and PV applications and market development.

Molecular engineering of polymer actuators for biomedical and industrial use

NASA Astrophysics Data System (ADS)

Banister, Mark; Eichorst, Rebecca; Gurr, Amy; Schweitzer, Georgette; Geronov, Yordan; Rao, Pavalli; McGrath, Dominic

2012-04-01

Five key materials engineering components and how each component impacted the working performance of a polymer actuator material are investigated. In our research we investigated the change of actuation performance that occurred with each change we made to the material. We investigated polymer crosslink density, polymer chain length, polymer gelation, type and density of reactive units, as well as the addition of binders to the polymer matrix. All five play a significant role and need to be addressed at the molecular level to optimize a polymer gel for use as a practical actuator material for biomedical and industrial use.

Oscillating-flow loss test results in rectangular heat exchanger passages

NASA Technical Reports Server (NTRS)

Wood, J. Gary

1991-01-01

Test results of oscillating flow losses in rectangular heat exchanger passages of various aspect ratios are given. This work was performed in support of the design of a free-piston Stirling engine (FPSE) for a dynamic space power conversion system. Oscillating flow loss testing was performed using an oscillating flow rig, which was based on a variable stroke and variable frequency linear drive motor. Tests were run over a range of oscillating flow parameters encompassing the flow regimes of the proposed engine design. Test results are presented in both tabular and graphical form and are compared against analytical predictions.

Development of the Functional Flow Block Diagram for the J-2X Rocket Engine System

NASA Technical Reports Server (NTRS)

White, Thomas; Stoller, Sandra L.; Greene, WIlliam D.; Christenson, Rick L.; Bowen, Barry C.

2007-01-01

The J-2X program calls for the upgrade of the Apollo-era Rocketdyne J-2 engine to higher power levels, using new materials and manufacturing techniques, and with more restrictive safety and reliability requirements than prior human-rated engines in NASA history. Such requirements demand a comprehensive systems engineering effort to ensure success. Pratt & Whitney Rocketdyne system engineers performed a functional analysis of the engine to establish the functional architecture. J-2X functions were captured in six major operational blocks. Each block was divided into sub-blocks or states. In each sub-block, functions necessary to perform each state were determined. A functional engine schematic consistent with the fidelity of the system model was defined for this analysis. The blocks, sub-blocks, and functions were sequentially numbered to differentiate the states in which the function were performed and to indicate the sequence of events. The Engine System was functionally partitioned, to provide separate and unique functional operators. Establishing unique functional operators as work output of the System Architecture process is novel in Liquid Propulsion Engine design. Each functional operator was described such that its unique functionality was identified. The decomposed functions were then allocated to the functional operators both of which were the inputs to the subsystem or component performance specifications. PWR also used a novel approach to identify and map the engine functional requirements to customer-specified functions. The final result was a comprehensive Functional Flow Block Diagram (FFBD) for the J-2X Engine System, decomposed to the component level and mapped to all functional requirements. This FFBD greatly facilitates component specification development, providing a well-defined trade space for functional trades at the subsystem and component level. It also provides a framework for function-based failure modes and effects analysis (FMEA), and a rigorous baseline for the functional architecture.

Testing for the J-2X Upper Stage Engine

NASA Technical Reports Server (NTRS)

Buzzell, James C.

2010-01-01

NASA selected the J-2X Upper Stage Engine in 2006 to power the upper stages of the Ares I crew launch vehicle and the Ares V cargo launch vehicle. Based on the proven Saturn J-2 engine, this new engine will provide 294,000 pounds of thrust and a specific impulse of 448 seconds, making it the most efficient gas generator cycle engine in history. The engine's guiding philosophy emerged from the Exploration Systems Architecture Study (ESAS) in 2005. Goals established then called for vehicles and components based, where feasible, on proven hardware from the Space Shuttle, commercial, and other programs, to perform the mission and provide an order of magnitude greater safety. Since that time, the team has made unprecedented progress. Ahead of the other elements of the Constellation Program architecture, the team has progressed through System Requirements Review (SRR), System Design Review (SDR), Preliminary Design Review (PDR), and Critical Design Review (CDR). As of February 2010, more than 100,000 development engine parts have been ordered and more than 18,000 delivered. Approximately 1,300 of more than 1,600 engine drawings were released for manufacturing. A major factor in the J-2X development approach to this point is testing operations of heritage J-2 engine hardware and new J-2X components to understand heritage performance, validate computer modeling of development components, mitigate risk early in development, and inform design trades. This testing has been performed both by NASA and its J-2X prime contractor, Pratt & Whitney Rocketdyne (PWR). This body of work increases the likelihood of success as the team prepares for testing the J-2X powerpack and first development engine in calendar 2011. This paper will provide highlights of J-2X testing operations, engine test facilities, development hardware, and plans.

Employee motivation of senior engineers in aerospace companies in southern California: A qualitative case study

NASA Astrophysics Data System (ADS)

Banh, My-Le

The purpose of this qualitative exploratory case study was to explore the lack of motivation of engineers with more than 15 years of experience working in aerospace companies in southern California. The sample size for this study consisted of 18 senior engineers. These participants held either a bachelor's or master's degree in engineering fields. Participants were recruited through networking with colleagues and snowball sampling. The data was collected through face-to-face and phone interviews. Participants also had the opportunity to review their responses after the interview. The data analysis resulted in 12 themes regarding the participants' perception of motivation. The top six predominant themes were (1) challenging and new assignments, (2) commitment, (3) opportunity, (4) supporting from managers, (5) team spirit, and (6) open communication. The study resulted in an in-depth understanding of how important motivation is to senior engineers. Based on the findings, leaders should create opportunities for senior employees to work on challenging assignments, acquire autonomy, and obtain more responsibilities. Providing such opportunities may motivate employees to perform well and committee with the organizations.

Concurrent Engineering Working Group White Paper Distributed Collaborative Design: The Next Step in Aerospace Concurrent Engineering

NASA Technical Reports Server (NTRS)

Hihn, Jairus; Chattopadhyay, Debarati; Karpati, Gabriel; McGuire, Melissa; Panek, John; Warfield, Keith; Borden, Chester

2011-01-01

As aerospace missions grow larger and more technically complex in the face of ever tighter budgets, it will become increasingly important to use concurrent engineering methods in the development of early conceptual designs because of their ability to facilitate rapid assessments and trades of performance, cost and schedule. To successfully accomplish these complex missions with limited funding, it is essential to effectively leverage the strengths of individuals and teams across government, industry, academia, and international agencies by increased cooperation between organizations. As a result, the existing concurrent engineering teams will need to increasingly engage in distributed collaborative concurrent design. The purpose of this white paper is to identify a near-term vision for the future of distributed collaborative concurrent engineering design for aerospace missions as well as discuss the challenges to achieving that vision. The white paper also documents the advantages of creating a working group to investigate how to engage the expertise of different teams in joint design sessions while enabling organizations to maintain their organizations competitive advantage.

Design Concepts for Cooled Ceramic Composite Turbine Vane

NASA Technical Reports Server (NTRS)

Boyle, Robert J.; Parikh, Ankur H.; Nagpal, VInod K.

2015-01-01

The objective of this work was to develop design concepts for a cooled ceramic vane to be used in the first stage of the High Pressure Turbine(HPT). To insure that the design concepts were relevant to the gas turbine industry needs, Honeywell International Inc. was subcontracted to provide technical guidance for this work. The work performed under this contract can be divided into three broad categories. The first was an analysis of the cycle benefits arising from the higher temperature capability of Ceramic Matrix Composite(CMC) compared with conventional metallic vane materials. The second category was a series of structural analyses for variations in the internal configuration of first stage vane for the High Pressure Turbine(HPT) of a CF6 class commercial airline engine. The third category was analysis for a radial cooled turbine vanes for use in turboshaft engine applications. The size, shape and internal configuration of the turboshaft engine vanes were selected to investigate a cooling concept appropriate to small CMC vanes.

NASA Ames summary high school apprenticeship research program, 1983 research papers

NASA Technical Reports Server (NTRS)

Powell, P.

1984-01-01

Engineering enrollments are rising in universities; however, the graduate engineer shortage continues. Particularly, women and minorities will be underrepresented for years to come. As one means of solving this shortage, Federal agencies facing future scientific and technological challenges were asked to participate in the Summer High School Apprenticeship Research Program (SHARP). This program was created 4 years ago to provide an engineering experience for gifted female and minority high school students at an age when they could still make career and education decisions. The SHARP Program is designed for high school juniors (women and minorities) who are U.S. citizens, are 16 years old, and who have unusually high promise in mathematics and science through outstanding academic performance in high school. Students who are accepted into this summer program will earn as they learn by working 8 hours a day in a 5-day work week. This work-study program features weekly field trips, lectures and written reports, and job experience related to the student's career interests.

Propulsion Health Monitoring for Enhanced Safety

NASA Technical Reports Server (NTRS)

Butz, Mark G.; Rodriguez, Hector M.

2003-01-01

This report presents the results of the NASA contract Propulsion System Health Management for Enhanced Safety performed by General Electric Aircraft Engines (GE AE), General Electric Global Research (GE GR), and Pennsylvania State University Applied Research Laboratory (PSU ARL) under the NASA Aviation Safety Program. This activity supports the overall goal of enhanced civil aviation safety through a reduction in the occurrence of safety-significant propulsion system malfunctions. Specific objectives are to develop and demonstrate vibration diagnostics techniques for the on-line detection of turbine rotor disk cracks, and model-based fault tolerant control techniques for the prevention and mitigation of in-flight engine shutdown, surge/stall, and flameout events. The disk crack detection work was performed by GE GR which focused on a radial-mode vibration monitoring technique, and PSU ARL which focused on a torsional-mode vibration monitoring technique. GE AE performed the Model-Based Fault Tolerant Control work which focused on the development of analytical techniques for detecting, isolating, and accommodating gas-path faults.

Exploration Medical Capability System Engineering Introduction and Vision

NASA Technical Reports Server (NTRS)

Mindock, J.; Reilly, J.

2017-01-01

Human exploration missions to beyond low Earth orbit destinations such as Mars will require more autonomous capability compared to current low Earth orbit operations. For the medical system, lack of consumable resupply, evacuation opportunities, and real-time ground support are key drivers toward greater autonomy. Recognition of the limited mission and vehicle resources available to carry out exploration missions motivates the Exploration Medical Capability (ExMC) Element's approach to enabling the necessary autonomy. The Element's work must integrate with the overall exploration mission and vehicle design efforts to successfully provide exploration medical capabilities. ExMC is applying systems engineering principles and practices to accomplish its integrative goals. This talk will briefly introduce the discipline of systems engineering and key points in its application to exploration medical capability development. It will elucidate technical medical system needs to be met by the systems engineering work, and the structured and integrative science and engineering approach to satisfying those needs, including the development of shared mental and qualitative models within and external to the human health and performance community. These efforts are underway to ensure relevancy to exploration system maturation and to establish medical system development that is collaborative with vehicle and mission design and engineering efforts.

Effect of Operating Conditions and Design on Afterburner Performance

NASA Technical Reports Server (NTRS)

Fleming, W. A.; Gabriel, D. S.; Lundin, B. T.

1956-01-01

Afterburners for turbojet engines have, within the past decade, found increasing application in service aircraft. Practically all engines manufactured today are equipped with some form of afterburner, and its use has increased from what was originally a short-period thrust-augmentation application to an essential feature of the turbojet propulsion system for flight at supersonic speeds. The design of these afterburners has been based on extensive research and development effort in expanded laboratory facilities by both the NACA and the American engine industry. Most of the work of the engine industry, however, has either not been published or is not generally available owing to its proprietary nature. Consequently, the main bulk of research information available for summary and discussion is of NACA origin. However, because industrial afterburner development has closely followed NACA research, the omission is more one of technical detail than method or concept. One principal difficulty encountered in summarizing the work in this field is that sufficient knowledge does not yet exist to rationally or directly integrate the available background of basic combustion principles into combustor design. A further difficulty is that most of the experimental investigations that have been conducted were directed chiefly toward the development of specific afterburners for various engines rather than to the accumulation of systematic data. This work has, nonetheless, provided not only substantial improvements in the performance of afterburners but also a large fund of experimental data and an extensive background of experience in the field. Consequently, it is the purpose of the present chapter to summarize the many, and frequently unrelated, experimental investigations that have been conducted rather than to formulate a set of design rules. In the treatment of this material an effort has been made, however, to convey to the reader the "know how" acquired by research engineers in the course of afterburner studies.

Parallel Performance of a Combustion Chemistry Simulation

DOE PAGES

Skinner, Gregg; Eigenmann, Rudolf

1995-01-01

We used a description of a combustion simulation's mathematical and computational methods to develop a version for parallel execution. The result was a reasonable performance improvement on small numbers of processors. We applied several important programming techniques, which we describe, in optimizing the application. This work has implications for programming languages, compiler design, and software engineering.

Risk-Based Probabilistic Approach to Aeropropulsion System Assessment

NASA Technical Reports Server (NTRS)

Tong, Michael T.

2002-01-01

In an era of shrinking development budgets and resources, where there is also an emphasis on reducing the product development cycle, the role of system assessment, performed in the early stages of an engine development program, becomes very critical to the successful development of new aeropropulsion systems. A reliable system assessment not only helps to identify the best propulsion system concept among several candidates, it can also identify which technologies are worth pursuing. This is particularly important for advanced aeropropulsion technology development programs, which require an enormous amount of resources. In the current practice of deterministic, or point-design, approaches, the uncertainties of design variables are either unaccounted for or accounted for by safety factors. This could often result in an assessment with unknown and unquantifiable reliability. Consequently, it would fail to provide additional insight into the risks associated with the new technologies, which are often needed by decision makers to determine the feasibility and return-on-investment of a new aircraft engine. In this work, an alternative approach based on the probabilistic method was described for a comprehensive assessment of an aeropropulsion system. The statistical approach quantifies the design uncertainties inherent in a new aeropropulsion system and their influences on engine performance. Because of this, it enhances the reliability of a system assessment. A technical assessment of a wave-rotor-enhanced gas turbine engine was performed to demonstrate the methodology. The assessment used probability distributions to account for the uncertainties that occur in component efficiencies and flows and in mechanical design variables. The approach taken in this effort was to integrate the thermodynamic cycle analysis embedded in the computer code NEPP (NASA Engine Performance Program) and the engine weight analysis embedded in the computer code WATE (Weight Analysis of Turbine Engines) with the fast probability integration technique (FPI). FPI was developed by Southwest Research Institute under contract with the NASA Glenn Research Center. The results were plotted in the form of cumulative distribution functions and sensitivity analyses and were compared with results from the traditional deterministic approach. The comparison showed that the probabilistic approach provides a more realistic and systematic way to assess an aeropropulsion system. The current work addressed the application of the probabilistic approach to assess specific fuel consumption, engine thrust, and weight. Similarly, the approach can be used to assess other aspects of aeropropulsion system performance, such as cost, acoustic noise, and emissions. Additional information is included in the original extended abstract.

48 CFR 1852.227-11 - Patent Rights-Retention by the Contractor (Short Form).

Code of Federal Regulations, 2011 CFR

2011-10-01

... Technology Reporting Web site http://invention.nasa.gov. (End of addition) (f)(5) The Contractor shall... of tier, for experimental, developmental, research, design, or engineering work to be performed by...

Ford works IFM on WHC

NASA Image and Video Library

2012-11-06

ISS033-E-018790 (6 Nov. 2012) --- NASA astronaut Kevin Ford, Expedition 33 flight engineer, performs in-flight maintenance on the Waste and Hygiene Compartment (WHC) toilet facilities in the Unity node of the International Space Station.

Two-dimensional model of a Space Station Freedom thermal energy storage canister

NASA Astrophysics Data System (ADS)

Kerslake, Thomas W.; Ibrahim, Mounir B.

1990-08-01

The Solar Dynamic Power Module being developed for Space Station Freedom uses a eutectic mixture of LiF-CaF2 phase change salt contained in toroidal canisters for thermal energy storage. Results are presented from heat transfer analyses of the phase change salt containment canister. A 2-D, axisymmetric finite difference computer program which models the canister walls, salt, void, and heat engine working fluid coolant was developed. Analyses included effects of conduction in canister walls and solid salt, conduction and free convection in liquid salt, conduction and radiation across salt vapor filled void regions and forced convection in the heat engine working fluid. Void shape, location, growth or shrinkage (due to density difference between the solid and liquid salt phases) were prescribed based on engineering judgement. The salt phase change process was modeled using the enthalpy method. Discussion of results focuses on the role of free-convection in the liquid salt on canister heat transfer performance. This role is shown to be important for interpreting the relationship between ground based canister performance (in l-g) and expected on-orbit performance (in micro-g). Attention is also focused on the influence of void heat transfer on canister wall temperature distributions. The large thermal resistance of void regions is shown to accentuate canister hot spots and temperature gradients.

Two-dimensional model of a Space Station Freedom thermal energy storage canister

NASA Astrophysics Data System (ADS)

Kerslake, Thomas W.; Ibrahim, Mounir B.

The Solar Dynamic Power Module being developed for Space Station Freedom uses a eutectic mixture of LiF-CaF2 phase change salt contained in toroidal canisters for thermal energy storage. Results are presented from heat transfer analyses of the phase-change salt containment canister. A 2-D, axisymmetric finite-difference computer program which models the canister walls, salt, void, and heat engine working fluid coolant was developed. Analyses included effects of conduction in canister walls and solid salt, conduction and free convection in liquid salt, conduction and radiation across salt vapor filled void regions, and forced convection in the heat engine working fluid. Void shape, location, and growth or shrinkage (due to density difference between the solid and liquid salt phases) were prescribed based on engineering judgement. The salt phase change process was modeled using the enthalpy method. Discussion of results focuses on the role of free-convection in the liquid salt on canister heat transfer performance. This role is shown to be important for interpreting the relationship between groundbased canister performance (in 1-g) and expected on-orbit performance (in micro-g). Attention is also focused on the influence of void heat transfer on canister wall temperature distributions. The large thermal resistance of void regions is shown to accentuate canister hot spots and temperature gradients.

Two-dimensional model of a Space Station Freedom thermal energy storage canister

NASA Technical Reports Server (NTRS)

Kerslake, Thomas W.; Ibrahim, Mounir B.

1990-01-01

The Solar Dynamic Power Module being developed for Space Station Freedom uses a eutectic mixture of LiF-CaF2 phase change salt contained in toroidal canisters for thermal energy storage. Results are presented from heat transfer analyses of the phase-change salt containment canister. A 2-D, axisymmetric finite-difference computer program which models the canister walls, salt, void, and heat engine working fluid coolant was developed. Analyses included effects of conduction in canister walls and solid salt, conduction and free convection in liquid salt, conduction and radiation across salt vapor filled void regions, and forced convection in the heat engine working fluid. Void shape, location, and growth or shrinkage (due to density difference between the solid and liquid salt phases) were prescribed based on engineering judgement. The salt phase change process was modeled using the enthalpy method. Discussion of results focuses on the role of free-convection in the liquid salt on canister heat transfer performance. This role is shown to be important for interpreting the relationship between groundbased canister performance (in 1-g) and expected on-orbit performance (in micro-g). Attention is also focused on the influence of void heat transfer on canister wall temperature distributions. The large thermal resistance of void regions is shown to accentuate canister hot spots and temperature gradients.

Two-dimensional model of a Space Station Freedom thermal energy storage canister

NASA Technical Reports Server (NTRS)

Kerslake, Thomas W.; Ibrahim, Mounir B.

1990-01-01

The Solar Dynamic Power Module being developed for Space Station Freedom uses a eutectic mixture of LiF-CaF2 phase change salt contained in toroidal canisters for thermal energy storage. Results are presented from heat transfer analyses of the phase change salt containment canister. A 2-D, axisymmetric finite difference computer program which models the canister walls, salt, void, and heat engine working fluid coolant was developed. Analyses included effects of conduction in canister walls and solid salt, conduction and free convection in liquid salt, conduction and radiation across salt vapor filled void regions and forced convection in the heat engine working fluid. Void shape, location, growth or shrinkage (due to density difference between the solid and liquid salt phases) were prescribed based on engineering judgement. The salt phase change process was modeled using the enthalpy method. Discussion of results focuses on the role of free-convection in the liquid salt on canister heat transfer performance. This role is shown to be important for interpreting the relationship between ground based canister performance (in l-g) and expected on-orbit performance (in micro-g). Attention is also focused on the influence of void heat transfer on canister wall temperature distributions. The large thermal resistance of void regions is shown to accentuate canister hot spots and temperature gradients.

Corrosion detection and evolution monitoring in reinforced concrete structures by the use of fiber Bragg grating sensor

NASA Astrophysics Data System (ADS)

Ali-Alvarez, S.; Ferdinand, P.; Magne, S.; Nogueira, R. P.

2013-04-01

Corrosion of reinforced bar (rebar) in concrete structures represents a major issue in civil engineering works, being its detection and evolution a challenge for the applied research. In this work, we present a new methodology to corrosion detection in reinforced concrete structures, by combining Fiber Bragg Grating (FBG) sensors with the electrochemical and physical properties of rebar in a simplified assembly. Tests in electrolytic solutions and concrete were performed for pitting and general corrosion. The proposed Structural Health Monitoring (SHM) methodology constitutes a direct corrosion measurement potentially useful to implement or improve Condition-Based Maintenance (CBM) program for civil engineering concrete structures.

The Stanford how things work project

NASA Technical Reports Server (NTRS)

Fikes, Richard; Gruber, Tom; Iwasaki, Yumi

1994-01-01

We provide an overview of the Stanford How Things Work (HTW) project, an ongoing integrated collection of research activities in the Knowledge Systems Laboratory at Stanford University. The project is developing technology for representing knowledge about engineered devices in a form that enables the knowledge to be used in multiple systems for multiple reasoning tasks and reasoning methods that enable the represented knowledge to be effectively applied to the performance of the core engineering task of simulating and analyzing device behavior. The central new capabilities currently being developed in the project are automated assistance with model formulation and with verification that a design for an electro-mechanical device satisfies its functional specification.

The Unruh quantum Otto engine

NASA Astrophysics Data System (ADS)

Arias, Enrique; de Oliveira, Thiago R.; Sarandy, M. S.

2018-02-01

We introduce a quantum heat engine performing an Otto cycle by using the thermal properties of the quantum vacuum. Since Hawking and Unruh, it has been established that the vacuum space, either near a black hole or for an accelerated observer, behaves as a bath of thermal radiation. In this work, we present a fully quantum Otto cycle, which relies on the Unruh effect for a single quantum bit (qubit) in contact with quantum vacuum fluctuations. By using the notions of quantum thermodynamics and perturbation theory we obtain that the quantum vacuum can exchange heat and produce work on the qubit. Moreover, we obtain the efficiency and derive the conditions to have both a thermodynamic and a kinematic cycle in terms of the initial populations of the excited state, which define a range of allowed accelerations for the Unruh engine.

Energy and Exergy Analysis of a Diesel Engine Fuelled with Diesel and Simarouba Biodiesel Blends

NASA Astrophysics Data System (ADS)

Panigrahi, Nabnit; Mohanty, Mahendra Kumar; Mishra, Sruti Ranjan; Mohanty, Ramesh Chandra

2018-02-01

This article intends to determine the available work and various losses of a diesel engine fuelled with diesel and SB20 (20 % Simarouba biodiesel by volume blended with 80 % diesel by volume). The energy and exergy analysis were carried out by using first law and second law of thermodynamics respectively. The experiments were carried out on a 3.5 kW compression ignition engine. The analysis was conducted on per mole of fuel basis. The energy analysis indicates that about 37.23 and 37.79 % of input energy is converted into the capacity to do work for diesel and SB20 respectively. The exergetic efficiency was 34.8 and 35 % for diesel and Simarouba respectively. Comparative study indicates that the energetic and exergetic performance of SB20 resembles with that of diesel fuel.

Engine-Out Capabilities Assessment of Heavy Lift Launch Vehicles

NASA Technical Reports Server (NTRS)

Holladay, Jon; Baggett, Keithe; Thrasher, Chad; Bellamy, K. Scott; Feldman, Stuart

2012-01-01

Engine-out (EO) is a condition that might occur during flight due to the failure of one or more engines. Protection against this occurrence can be called engine-out capability (EOC) whereupon significantly improved loss of mission may occur, in addition to reduction in performance and increased cost. A standardized engine-out capability has not been studied exhaustively as it pertains to space launch systems. This work presents results for a specific vehicle design with specific engines, but also uniquely provides an approach to realizing the necessity of EOC for any launch vehicle system design. A derived top-level approach to engine-out philosophy for a heavy lift launch vehicle is given herein, based on an historical assessment of launch vehicle capabilities. The methodology itself is not intended to present a best path forward, but instead provides three parameters for assessment of a particular vehicle. Of the several parameters affected by this EOC, the three parameters of interest in this research are reliability (Loss of Mission (LOM) and Loss of Crew (LOC)), vehicle performance, and cost. The intent of this effort is to provide insight into the impacts of EO capability on these parameters. The effects of EOC on reliability, performance and cost are detailed, including how these important launch vehicle metrics can be combined to assess what could be considered overall launch vehicle affordability. In support of achieving the first critical milestone (Mission Concept Review) in the development of the Space Launch System (SLS), a team assessed two-stage, large-diameter vehicles that utilized liquid oxygen (LOX)-RP propellants in the First Stage and LOX/LH2 propellant in the Upper Stage. With multiple large thrust-class engines employed on the stages, engine-out capability could be a significant driver to mission success. It was determined that LOM results improve by a factor of five when assuming EOC for both Core Stage (CS) (first stage) and Upper Stage (US) EO, assuming a reference launch vehicle with 5 RP engines on the CS and 3 LOX/LH2 engines on the US. The benefit of adding both CS and US engine-out capability is significant. When adding EOC for either first or second stages, there is less than a 20% benefit. Performance analysis has shown that if the vehicle is not protected for EO during the first part of the flight and only protected in the later part of the flight, there is a diminishing performance penalty, as indicated by failures occurring in the first stage at different times. This work did not consider any options to abort. While adding an engine for EOC drives cost upward, the impact depends on the number of needed engines manufactured per year and the launch manifest. There is a significant cost savings if multiple flights occur within one year. Flying two flights per year would cost approximately $4,000 per pound less than the same configuration with one flight per year, assuming both CS and US EOC. The cost is within 15% of the cost of one flight per year with no engine-out capability for the same vehicle. This study can be extended to other launch vehicles. While the numbers given in this paper are specific to a certain vehicle configuration, the process requires only a high level of data to allow an analyst to draw conclusions. The weighting of each of the identified parameters will determine the optimization of each launch vehicle. The results of this engine-out assessment provide a means to understand this optimization while maintaining an unbiased perspective.

Thermal barrier coatings application in diesel engines

NASA Technical Reports Server (NTRS)

Fairbanks, J. W.

1995-01-01

Commercial use of thermal barrier coatings in diesel engines began in the mid 70's by Dr. Ingard Kvernes at the Central Institute for Industrial Research in Oslo, Norway. Dr. Kvernes attributed attack on diesel engine valves and piston crowns encountered in marine diesel engines in Norwegian ships as hot-corrosion attributed to a reduced quality of residual fuel. His solution was to coat these components to reduce metal temperature below the threshold of aggressive hot-corrosion and also provide protection. Roy Kamo introduced thermal barrier coatings in his 'Adiabatic Diesel Engine' in the late 70's. Kamo's concept was to eliminate the engine block water cooling system and reduce heat losses. Roy reported significant performance improvements in his thermally insulated engine at the SAE Congress in 1982. Kamo's work stimulates major programs with insulated engines, particularly in Europe. Most of the major diesel engine manufacturers conducted some level of test with insulated combustion chamber components. They initially ran into increased fuel consumption. The German engine consortium had Prof. Woschni of the Technical Institute in Munich. Woschni conducted testing with pistons with air gaps to provide the insulation effects. Woschni indicated the hot walls of the insulated engine created a major increase in heat transfer he refers to as 'convection vive.' Woschni's work was a major factor in the abrupt curtailment of insulated diesel engine work in continental Europe. Ricardo in the UK suggested that combustion should be reoptimized for the hot-wall effects of the insulated combustion chamber and showed under a narrow range of conditions fuel economy could be improved. The Department of Energy has supported thermal barrier coating development for diesel engine applications. In the Clean Diesel - 50 Percent Efficient (CD-50) engine for the year 2000, thermal barrier coatings will be used on piston crowns and possibly other components. The primary purpose of the thermal barrier coatings will be to reduce thermal fatigue as the engine peak cylinder pressure will nearly be doubled. As the coatings result in higher available energy in the exhaust gas, efficiency gains are achieved through use of this energy by turbochargers, turbocompounding or thermoelectric generators.

European research and commercialisation activities in the field of tissue engineering and liver support in world wide competition.

PubMed

Marx, U; Bushnaq, H; Yalcin, E

1998-02-01

Tissue engineering is seen as an interesting field of technology which could improve medical therapy and could also be considered as a commercial opportunity for the European biotechnological industry. Research in the state of the art of science using the MedLine and the Science Citation Index databases, in the patent situation and of the industry dealing with tissue engineering was done. A special method, based on the Science Citation Index Journal Citation Report 1993, for evaluating scientific work was defined. The main countries working in the field of tissue engineering were evaluated in regard to their scientific performance and their patents. The R&D of German industry was investigated as an exemplary European country. Out of all activities, different tissues were rated with respect to the attention received from research and industry and with regard to the frequency in which patents were applied for. USA, Germany and Japan rank first in most tissues, especially liver. After comparing German patents with the German scientific and industrial work, it seems that the potential in German patents and research is underestimated by German industry and inefficiently exploited.

Numerical prediction of turbulent oscillating flow and associated heat transfer

NASA Technical Reports Server (NTRS)

Koehler, W. J.; Patankar, S. V.; Ibele, W. E.

1991-01-01

A crucial point for further development of engines is the optimization of its heat exchangers which operate under oscillatory flow conditions. It has been found that the most important thermodynamic uncertainties in the Stirling engine designs for space power are in the heat transfer between gas and metal in all engine components and in the pressure drop across the heat exchanger components. So far, performance codes cannot predict the power output of a Stirling engine reasonably enough if used for a wide variety of engines. Thus, there is a strong need for better performance codes. However, a performance code is not concerned with the details of the flow. This information must be provided externally. While analytical relationships exist for laminar oscillating flow, there has been hardly any information about transitional and turbulent oscillating flow, which could be introduced into the performance codes. In 1986, a survey by Seume and Simon revealed that most Stirling engine heat exchangers operate in the transitional and turbulent regime. Consequently, research has since focused on the unresolved issue of transitional and turbulent oscillating flow and heat transfer. Since 1988, the University of Minnesota oscillating flow facility has obtained experimental data about transitional and turbulent oscillating flow. However, since the experiments in this field are extremely difficult, lengthy, and expensive, it is advantageous to numerically simulate the flow and heat transfer accurately from first principles. Work done at the University of Minnesota on the development of such a numerical simulation is summarized.

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.

Predicting performance in a first engineering calculus course: implications for interventions

NASA Astrophysics Data System (ADS)

Hieb, Jeffrey L.; Lyle, Keith B.; Ralston, Patricia A. S.; Chariker, Julia

2015-01-01

At the University of Louisville, a large, urban institution in the south-east United States, undergraduate engineering students take their mathematics courses from the school of engineering. In the fall of their freshman year, engineering students take Engineering Analysis I, a calculus-based engineering analysis course. After the first two weeks of the semester, many students end up leaving Engineering Analysis I and moving to a mathematics intervention course. In an effort to retain more students in Engineering Analysis I, the department collaborated with university academic support services to create a summer intervention programme. Students were targeted for the summer programme based on their score on an algebra readiness exam (ARE). In a previous study, the ARE scores were found to be a significant predictor of retention and performance in Engineering Analysis I. This study continues that work, analysing data from students who entered the engineering school in the fall of 2012. The predictive validity of the ARE was verified, and a hierarchical linear regression model was created using math American College Testing (ACT) scores, ARE scores, summer intervention participation, and several metacognitive and motivational factors as measured by subscales of the Motivated Strategies for Learning Questionnaire. In the regression model, ARE score explained an additional 5.1% of the variation in exam performance in Engineering Analysis I beyond math ACT score. Students took the ARE before and after the summer interventions and scores were significantly higher following the intervention. However, intervention participants nonetheless had lower exam scores in Engineering Analysis I. The following factors related to motivation and learning strategies were found to significantly predict exam scores in Engineering Analysis I: time and study environment management, internal goal orientation, and test anxiety. The adjusted R2 for the full model was 0.42, meaning that the model could explain 42% of the variation in Engineering Analysis I exam scores.

Bringing Art, Music, Theater and Dance Students into Earth and Space Science Research Labs: A New Art Prize Science and Engineering Artists-in-Residence Program

NASA Astrophysics Data System (ADS)

Moldwin, M.; Mexicotte, D.

2017-12-01

A new Arts/Lab Student Residence program was developed at the University of Michigan that brings artists into a research lab. Science and Engineering undergraduate and graduate students working in the lab describe their research and allow the artists to shadow them to learn more about the work. The Arts/Lab Student Residencies are designed to be unique and fun, while encouraging interdisciplinary learning and creative production by exposing students to life and work in an alternate discipline's maker space - i.e. the artist in the engineering lab, the engineer in the artist's studio or performance space. Each residency comes with a cash prize and the expectation that a work of some kind will be produced as a response to experience. The Moldwin Prize is designed for an undergraduate student currently enrolled in the Penny W. Stamps School of Art & Design, the Taubman School of Architecture and Urban Planning or the School of Music, Theatre and Dance who is interested in exchange and collaboration with students engaged in research practice in an engineering lab. No previous science or engineering experience is required, although curiosity and a willingness to explore are essential! Students receiving the residency spend 20 hours over 8 weeks (February-April) participating with the undergraduate research team in the lab of Professor Mark Moldwin, which is currently doing work in the areas of space weather (how the Sun influences the space environment of Earth and society) and magnetic sensor development. The resident student artist will gain a greater understanding of research methodologies in the space and climate fields, data visualization and communication techniques, and how the collision of disciplinary knowledge in the arts, engineering and sciences deepens the creative practice and production of each discipline. The student is expected to produce a final work of some kind within their discipline that reflects, builds on, explores, integrates or traces their experience in the residency. This talk will describe the program, the inaugural year's outcomes, and plans to expand the program to other research labs.

Increase of Gas-Turbine Plant Efficiency by Optimizing Operation of Compressors

NASA Astrophysics Data System (ADS)

Matveev, V.; Goriachkin, E.; Volkov, A.

2018-01-01

The article presents optimization method for improving of the working process of axial compressors of gas turbine engines. Developed method allows to perform search for the best geometry of compressor blades automatically by using optimization software IOSO and CFD software NUMECA Fine/Turbo. The calculation of the compressor parameters was performed for work and stall point of its performance map on each optimization step. Study was carried out for seven-stage high-pressure compressor and three-stage low-pressure compressors. As a result of optimization, improvement of efficiency was achieved for all investigated compressors.

Axisymmetric Numerical Modeling of Pulse Detonation Rocket Engines

NASA Technical Reports Server (NTRS)

Morris, Christopher I.

2005-01-01

Pulse detonation rocket engines (PDREs) have generated research interest in recent years as a chemical propulsion system potentially offering improved performance and reduced complexity compared to conventional rocket engines. The detonative mode of combustion employed by these devices offers a thermodynamic advantage over the constant-pressure deflagrative combustion mode used in conventional rocket engines and gas turbines. However, while this theoretical advantage has spurred considerable interest in building PDRE devices, the unsteady blowdown process intrinsic to the PDRE has made realistic estimates of the actual propulsive performance problematic. The recent review article by Kailasanath highlights some of the progress that has been made in comparing the available experimental measurements with analytical and numerical models. In recent work by the author, a quasi-one-dimensional, finite rate chemistry CFD model was utilized to study the gasdynamics and performance characteristics of PDREs over a range of blowdown pressure ratios from 1-1000. Models of this type are computationally inexpensive, and enable first-order parametric studies of the effect of several nozzle and extension geometries on PDRE performance over a wide range of conditions. However, the quasi-one-dimensional approach is limited in that it cannot properly capture the multidimensional blast wave and flow expansion downstream of the PDRE, nor can it resolve nozzle flow separation if present. Moreover, the previous work was limited to single-pulse calculations. In this paper, an axisymmetric finite rate chemistry model is described and utilized to study these issues in greater detail. Example Mach number contour plots showing the multidimensional blast wave and nozzle exhaust plume are shown. The performance results are compared with the quasi-one-dimensional results from the previous paper. Both Euler and Navier-Stokes solutions are calculated in order to determine the effect of viscous effects in the nozzle flowfield. Additionally, comparisons of the model results to performance data from CalTech, as well as experimental flowfield measurements from Stanford University, are also reported.

NASA’s Space Launch System Engine Testing Heats Up

NASA Image and Video Library

2017-05-23

NASA engineers successfully conducted the second in a series of RS-25 flight controller tests on May 23, 2017, for the world’s most-powerful rocket. The 500-second test on the A-1 Test Stand at NASA’s Stennis Space Center in Mississippi marked another milestone toward launch of NASA’s new Space Launch System (SLS) rocket on its inaugural flight, the Exploration Mission-1 (EM-1). The SLS rocket, powered by four RS-25 engines, will provide 2 million pounds of thrust and work in conjunction with two solid rocket boosters. These are former space shuttle main engines, modified to perform at a higher level and with a new controller.

Elementary Education Program for Engineering by Dual System of Workshop and Teaching Program with Practical Subject

NASA Astrophysics Data System (ADS)

Hara, Toshitsugu

Elementary education program for engineering by the dual system combined with workshop program and teaching program with practical subject was discussed. The dual system which consists of several workshop programs and fundamental subjects (such as mathematics, English and physics) with practical material has been performed for the freshmen. The elementary workshop program (primary course) has four workshops and the related lectures. Fundamental subjects are taught with the practical or engineering texts. English subjects are taught by specified teachers who have ever worked in engineering field with English. The dual system was supported by such systems as the center for success initiative and the English education center.

Holographic heat engines

NASA Astrophysics Data System (ADS)

Johnson, Clifford V.

2014-10-01

It is shown that in theories of gravity where the cosmological constant is considered a thermodynamic variable, it is natural to use black holes as heat engines. Two examples are presented in detail using AdS charged black holes as the working substance. We notice that for static black holes, the maximally efficient traditional Carnot engine is also a Stirling engine. The case of negative cosmological constant supplies a natural realization of these engines in terms of the field theory description of the fluids to which they are holographically dual. We first propose a precise picture of how the traditional thermodynamic dictionary of holography is extended when the cosmological constant is dynamical and then conjecture that the engine cycles can be performed by using renormalization group flow. We speculate about the existence of a natural dual field theory counterpart to the gravitational thermodynamic volume.

The Development of Mobile Augmented Reality

DTIC Science & Technology

2012-01-01

working jointly with NRL, performed a domain analysis ( Gabbard et al., 2002) to create a context for usability engineering effort, performed formative...rectangle to provide a background enabled the fastest user performance ( Gabbard et al., 2007). Tracking the user’s head position relative to the real...thank Yohan Baillot, Reinhold Behringer, Blaine Bell, Dennis Brown, Aaron Bryden, Enylton Coelho, Elliot Cooper-Balis, Deborah Hix, Joseph Gabbard

Software Manages Documentation in a Large Test Facility

NASA Technical Reports Server (NTRS)

Gurneck, Joseph M.

2001-01-01

The 3MCS computer program assists and instrumentation engineer in performing the 3 essential functions of design, documentation, and configuration management of measurement and control systems in a large test facility. Services provided by 3MCS are acceptance of input from multiple engineers and technicians working at multiple locations;standardization of drawings;automated cross-referencing; identification of errors;listing of components and resources; downloading of test settings; and provision of information to customers.

Pressure Analysis

NASA Technical Reports Server (NTRS)

1990-01-01

FluiDyne Engineering Corporation, Minneapolis, MN is one of the world's leading companies in design and construction of wind tunnels. In its designing work, FluiDyne uses a computer program called GTRAN. With GTRAN, engineers create a design and test its performance on the computer before actually building a model; should the design fail to meet criteria, the system or any component part can be redesigned and retested on the computer, saving a great deal of time and money.

Space-Based Telescopes for the Actionable Refinement of Ephemeris Systems and Test Engineering

DTIC Science & Technology

2011-12-01

Space Surveillance Network STARE Space-based Telescopes for the Actionable Refinement of Ephemeris STK Satellite Toolkit SV Space Vehicle TAMU...vacuum bake out and visual inspection. Additionally, it is prescribed that these tests be performed in accordance with GSFC-STD-7000, more commonly...environment that a FV will see in orbit. Tools such as Solid Works and NX-Ideas can be used to build CAD models to visually validate engineering

History of the U.S. Army Corps of Engineers Engineering and Support Center, Huntsville 1993-1997

DTIC Science & Technology

1999-06-01

Patrick Moynihan initiated research into a magnetically levitated train ( MAGLEV ), Huntsville Division received the call to help with designs. When...the Missile Defense Data Center. Advanced Technology also performed a number of studies for Ordnance and Explosives Applied Technology and the MAGLEV ...contract had been closed out, and no follow-on work was expected-16 MAGLEV Perhaps the most unusual high-proflle project Huntsville Center

CrossTalk: The Journal of Defense Software Engineering. Volume 20, Number 3, March 2007

DTIC Science & Technology

2007-03-01

Capability Maturity Model ® Integration (CMMI®). CMU Software Engineering Institute <www.sei.cmu.edu/cmmi>. 5. ISO /IEC 27001 :2005. Information Security...international standards bodies – International Organization for Standardi- zation ( ISO ) and International Electro- technical Commission (IEC) – are working on a...number of projects that affect soft- ware security: • The ISO Technical Management Board (TMB) performs strategic planning and coordination for ISO

Systems Engineering Technical Leadership Development Program

DTIC Science & Technology

2012-08-30

technology-based competitive advantage can be part of firm’s business strategy.  Review the Porter Model . Return to Syllabus UNCLASSIFIED 66...Program 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR( S ) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7...PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES) Stevens Institute of Technology,Systems Engineering Research Center,Castle Point on the Hudson,Hoboken,NJ

Operation HARDTACK. Phase 2

DTIC Science & Technology

1959-07-01

Nevada Test Site. ditions, available equipment and material , and late criteria changes requesifd by the partici- "The Nevada tests will e held during...by visory personnel. H&N Field Engineers or the H&N Material TestsResident Engineer. The majority of material tests consisted of 3. Reports and...procurement of material and hol, date of request, date rquired, work to be equipment to be used in the test facilities pro- performed, and site or station

Improving the performance and emission characteristics of a single cylinder diesel engine having reentrant combustion chamber using diesel and Jatropha methyl esters.

PubMed

Premnath, S; Devaradjane, G

2015-11-01

The emissions from the Compression ignition (CI) engines introduce toxicity to the atmosphere. The undesirable carbon deposits from these engines are realized in the nearby static or dynamic systems such as vehicles, inhabitants, etc. The objective of this research work is to improve the performance and emission characteristics of a diesel engine in the modified re-entrant combustion chamber using a diesel and Jatropha methyl ester blend (J20) at three different injection pressures. From the literature, it is revealed that the shape of the combustion chamber and the fuel injection pressure have an impact on the performance and emission parameters of the CI engine. In this work, a re-entrant combustion chamber with three different fuel injection pressures (200, 220 and 240bars) has been used in the place of the conventional hemispherical combustion chamber for diesel and J20. From the experimental results, it is found that the re-entrant chamber improves the brake thermal efficiency of diesel and J20 in all the tested conditions. It is also found that the 20% blend of Jatropha methyl ester showed 4% improvement in the brake thermal efficiency in the re-entrant chamber at the maximum injection pressure. Environmental safety directly relates to the reduction in the undesirable effects on both living and non-living things. Currently environmental pollution is of major concern. Even with the stringent emission norms new methods are required to reduce the harmful effects from automobiles. The toxicity of carbon monoxide (CO) is well known. In the re-entrant combustion chamber, the amount of CO emission is reduced by 26% when compared with the conventional fuel operation of the engine. Moreover, the amount of smoke is reduced by 24% and hydrocarbons (HC) emission by 24%. Thus, the modified re-entrant combustion chamber reduces harmful pollutants such as unburned HC and CO as well as toxic smoke emissions. Copyright © 2015 Elsevier Inc. All rights reserved.

[The aging process and work: a case study in the maintenance engineering division of a public hospital in the city of São Paulo, Brazil].

PubMed

Sato, Andrea Toshye; Barros, Juliana de Oliveira; Jardim, Tatiana de Andrade; Ratier, Ana Paula Pelegrini; Lancman, Selma

2017-11-06

This study aimed to identify and analyze the relations between aging and work. This was a case study in the maintenance engineering division of a high-complexity hospital in the city of São Paulo, Brazil. In September and October 2015, 16 semi-structured interviews were held with the division heads and other workers with a minimum age of 50 years. The data were analyzed with thematic content analysis. Although the workers experienced difficulties resulting from the aging process, these did not prevent them from performing their work activities, since they developed strategies through their knowhow to compensate for their functional losses and/or declines. Still, they felt limited and demotivated due to the poor working conditions, outsourcing of the division, and the prevailing workload organization. Thus, in this division, the working conditions and organization had more impact than the aging process on the individuals' daily work routine.

Understanding safety and production risks in rail engineering planning and protection.

PubMed

Wilson, John R; Ryan, Brendan; Schock, Alex; Ferreira, Pedro; Smith, Stuart; Pitsopoulos, Julia

2009-07-01

Much of the published human factors work on risk is to do with safety and within this is concerned with prediction and analysis of human error and with human reliability assessment. Less has been published on human factors contributions to understanding and managing project, business, engineering and other forms of risk and still less jointly assessing risk to do with broad issues of 'safety' and broad issues of 'production' or 'performance'. This paper contains a general commentary on human factors and assessment of risk of various kinds, in the context of the aims of ergonomics and concerns about being too risk averse. The paper then describes a specific project, in rail engineering, where the notion of a human factors case has been employed to analyse engineering functions and related human factors issues. A human factors issues register for potential system disturbances has been developed, prior to a human factors risk assessment, which jointly covers safety and production (engineering delivery) concerns. The paper concludes with a commentary on the potential relevance of a resilience engineering perspective to understanding rail engineering systems risk. Design, planning and management of complex systems will increasingly have to address the issue of making trade-offs between safety and production, and ergonomics should be central to this. The paper addresses the relevant issues and does so in an under-published domain - rail systems engineering work.

Effect of soot on oil properties and wear of engine components

NASA Astrophysics Data System (ADS)

Green, D. A.; Lewis, R.

2007-09-01

The objective of the work outlined in this paper was to increase the understanding of the wear mechanisms that occur within a soot contaminated contact zone, to help in future development of a predictive wear model to assist in the automotive engine valve train design process. The paper builds on previous work by the author, through testing of different lubricants and increased levels of soot contamination. Wear testing has been carried out using specimens operating under realistic engine conditions, using a reciprocating test-rig specifically designed for this application, where a steel disc is held in a heated bath of oil and a steel ball is attached to a reciprocating arm (replicating a sliding elephant's foot valve train contact). Detailed analysis of the test specimens has been performed using scanning electron microscopy to identify wear features relating to the proposed wear mechanisms. Analysis of worn engine components from durability engine tests has also been carried out for a comparison between specimen tests and engine testing. To assist the understanding of the wear test results obtained, the physical properties of contaminated lubricants were investigated, through viscosity, traction and friction measurements. The results have revealed how varying lubrication conditions change the wear rate of engine components and determine the wear mechanism that dominates in specific situations. Testing has also shown the positive effects of advanced engine lubricants to reduce the amount of wear produced with soot present.

The role of aluminum in slow sand filtration.

PubMed

Weber-Shirk, Monroe L; Chan, Kwok Loon

2007-03-01

Engineering enhancement of slow sand filtration has been an enigma in large part because the mechanisms responsible for particle removal have not been well characterized. The presumed role of biological processes in the filter ripening process nearly precluded the possibility of enhancing filter performance since interventions to enhance biological activity would have required decreasing the quality of the influent water. In previous work, we documented that an acid soluble polymer controls filter performance. The new understanding that particle removal is controlled in large part by physical chemical mechanisms has expanded the possibilities of engineering slow sand filter performance. Herein, we explore the role of naturally occurring aluminum as a ripening agent for slow sand filters and the possibility of using a low dose of alum to improve filter performance or to ripen slow sand filters.

Russian EVA 39.

NASA Image and Video Library

2014-08-18

ISS040E099104 (08/18/2014) --- View of Cosmonaut Oleg Artemyev (blue stripe), Expedition 40 flight engineer outside the International Space Station, taken while performing maintenance work on the Russian segment during the Russian EVA 39 on Aug 18 2014.

iss034e033850

NASA Image and Video Library

2013-01-23

ISS034-E-033850 (23 Jan. 2013) --- Canadian Space Agency astronaut Chris Hadfield, Expedition 34 flight engineer, continues work to remove and replace the Service and Performance Checkout Unit (SPCU) Heat Exchanger inside the Quest airlock of the International Space Station.

Performance of a small compression ignition engine fuelled by liquified petroleum gas

NASA Astrophysics Data System (ADS)

Ambarita, Himsar; Yohanes Setyawan, Eko; Ginting, Sibuk; Naibaho, Waldemar

2017-09-01

In this work, a small air cooled single cylinder of diesel engine with a rated power of 2.5 kW at 3000 rpm is tested in two different modes. In the first mode, the CI engines run on diesel fuel mode. In the second mode, the CI engine run on liquified petroleum gas (LPG) mode. In order to simulate the load, a generator is employed. The load is fixed at 800 W and engine speed varies from 2400 rpm to 3400 rpm. The out power, specific fuel consumption, and brake thermal efficiency resulted from the engine in both modes are compared. The results show that the output power of the CI engine run on LPG fuel is comparable with the engine run on diesel fuel. However, the specific fuel consumption of the CI engine with LPG fuel is higher 17.53% in average in comparison with the CI engine run on diesel fuel. The efficiency of the CI engine with LPG fuel is lower 21.43% in average in comparison with the CI engine run on diesel fuel.

Performance Engineering Research Institute SciDAC-2 Enabling Technologies Institute Final Report

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

Lucas, Robert

2013-04-20

Enhancing the performance of SciDAC applications on petascale systems had high priority within DOE SC at the start of the second phase of the SciDAC program, SciDAC-2, as it continues to do so today. Achieving expected levels of performance on high-end computing (HEC) systems is growing ever more challenging due to enormous scale, increasing architectural complexity, and increasing application complexity. To address these challenges, the University of Southern California?s Information Sciences Institute organized the Performance Engineering Research Institute (PERI). PERI implemented a unified, tripartite research plan encompassing: (1) performance modeling and prediction; (2) automatic performance tuning; and (3) performance engineeringmore » of high profile applications. Within PERI, USC?s primary research activity was automatic tuning (autotuning) of scientific software. This activity was spurred by the strong user preference for automatic tools and was based on previous successful activities such as ATLAS, which automatically tuned components of the LAPACK linear algebra library, and other recent work on autotuning domain-specific libraries. Our other major component was application engagement, to which we devoted approximately 30% of our effort to work directly with SciDAC-2 applications. This report is a summary of the overall results of the USC PERI effort.« less

Effects of Injection Scheme on Rotating Detonation Engine Operation

NASA Astrophysics Data System (ADS)

Chacon, Fabian; Duvall, James; Gamba, Mirko

2017-11-01

In this work, we experimentally investigate the operation and performance characteristics of a rotating detonation engine (RDE) operated with different fuel injection schemes and operating conditions. In particular, we investigate the detonation and operation characteristics produced with an axial flow injector configuration and semi-impinging injector configurations. These are compared to the characteristics produced with a canonical radial injection system (AFRL injector). Each type produces a different flowfield and mixture distribution, leading to a different detonation initiation, injector dynamic response, and combustor pressure rise. By using a combination of diagnostics, we quantify the pressure loses and gains in the system, the ability to maintain detonation over a range of operating points, and the coupling between the detonation and the air/fuel feed lines. We particularly focus on how this coupling affects both the stability and the performance of the detonation wave. This work is supported by the DOE/UTSR program under project DE-FE0025315.

Non-equilibrium assembly of microtubules: from molecules to autonomous chemical robots.

PubMed

Hess, H; Ross, Jennifer L

2017-09-18

Biological systems have evolved to harness non-equilibrium processes from the molecular to the macro scale. It is currently a grand challenge of chemistry, materials science, and engineering to understand and mimic biological systems that have the ability to autonomously sense stimuli, process these inputs, and respond by performing mechanical work. New chemical systems are responding to the challenge and form the basis for future responsive, adaptive, and active materials. In this article, we describe a particular biochemical-biomechanical network based on the microtubule cytoskeletal filament - itself a non-equilibrium chemical system. We trace the non-equilibrium aspects of the system from molecules to networks and describe how the cell uses this system to perform active work in essential processes. Finally, we discuss how microtubule-based engineered systems can serve as testbeds for autonomous chemical robots composed of biological and synthetic components.

A parametric investigation on a solar dish-Stirling system

NASA Astrophysics Data System (ADS)

Gholamalizadeh, Ehsan; Chung, Jae Dong

2018-06-01

The aim of this study is to analyze the performance of a solar dish-Stirling system. A mathematical model for the overall thermal efficiency of the solar-powered high-temperature-differential dish-Stirling engine is described. This model takes into account pressure losses due to fluid friction which is internal to the engine, mechanical friction between the moving parts, actual heat transfer includes the effects of both internal and external irreversibilities of the cycle and finite regeneration processes time. Validation was done through comparison with the actual power output of the "EuroDish" system. Moreover, the effects of dish diameter and working fluid on the performance of the system were studied. An increase of about 7.2% was observed for the power output using hydrogen as the working fluid rather than helium. Also, the focal distance for any diameter of dish was calculated.

A 4-cylinder Stirling engine computer program with dynamic energy equations

NASA Technical Reports Server (NTRS)

Daniele, C. J.; Lorenzo, C. F.

1983-01-01

A computer program for simulating the steady state and transient performance of a four cylinder Stirling engine is presented. The thermodynamic model includes both continuity and energy equations and linear momentum terms (flow resistance). Each working space between the pistons is broken into seven control volumes. Drive dynamics and vehicle load effects are included. The model contains 70 state variables. Also included in the model are piston rod seal leakage effects. The computer program includes a model of a hydrogen supply system, from which hydrogen may be added to the system to accelerate the engine. Flow charts are provided.

Environmental and Mechanical Stability of Environmental Barrier Coated SA Tyrannohex SiC Composites Under Simulated Turbine Engine Environments

NASA Technical Reports Server (NTRS)

Zhu, Dongming; Halbig, Michael Charles; Sing, Mrityunjay

2014-01-01

The environmental stability and thermal gradient cyclic durability performance of SA Tyrannohex composites were investigated for turbine engine component applications. The work has been focused on investigating the combustion rig recession, cyclic thermal stress resistance and thermomechanical low cycle fatigue of uncoated and environmental barrier coated Tyrannohex SiC SA composites in simulated turbine engine combustion water vapor, thermal gradients, and mechanical loading conditions. Flexural strength degradations have been evaluated, and the upper limits of operating temperature conditions for the SA composite material systems are discussed based on the experimental results.

Thermo-Mechanical Cracking in Coated Media with a Cavity by a Moving Asperity Friction.

DTIC Science & Technology

1988-03-01

smmhhEohEEEoh ILL 11 O1-25 *I54 *.Nit III,’M " ’, Ot.S S S S S V S AD-A193 311 L . *M THE UNIVERSITY OF NEW MEXICO COLLEGE OF ENGINEERING BUREAU OF...Mechanical Engineering Department APR 06 IIM 1 University of New Mexico SID Technical Report No. ME-144(88)ONR-233-3 H Work performed under ONR Grant...With A Cavity By A Moving Asperity Friction by Frederick D. Ju and Tsu-Yen Chen Mechanical Engineering Department University of New Mexico Albuquerque

Peregrine Sustainer Motor Development

NASA Technical Reports Server (NTRS)

Brodell, Chuck; Franklin, Philip

2015-01-01

The Peregrine sounding rocket is an in-house NASA design that provides approximately 15 percent better performance than the motor it replaces. The design utilizes common materials and well-characterized architecture to reduce flight issues encountered with the current motors. It engages NASA design, analysts, test engineers and technicians, ballisticians, and systems engineers. The in-house work and collaboration within the government provides flexibility to efficiently accommodate design and program changes as the design matures and enhances the ability to meet schedule milestones. It provides a valuable tool to compare industry costs, develop contracts, and it develops foundational knowledge for the next generation of NASA engineers.

Experimental and artificial neural network based prediction of performance and emission characteristics of DI diesel engine using Calophyllum inophyllum methyl ester at different nozzle opening pressure

NASA Astrophysics Data System (ADS)

Vairamuthu, G.; Thangagiri, B.; Sundarapandian, S.

2018-01-01

The present work investigates the effect of varying Nozzle Opening Pressures (NOP) from 220 bar to 250 bar on performance, emissions and combustion characteristics of Calophyllum inophyllum Methyl Ester (CIME) in a constant speed, Direct Injection (DI) diesel engine using Artificial Neural Network (ANN) approach. An ANN model has been developed to predict a correlation between specific fuel consumption (SFC), brake thermal efficiency (BTE), exhaust gas temperature (EGT), Unburnt hydrocarbon (UBHC), CO, CO2, NOx and smoke density using load, blend (B0 and B100) and NOP as input data. A standard Back-Propagation Algorithm (BPA) for the engine is used in this model. A Multi Layer Perceptron network (MLP) is used for nonlinear mapping between the input and the output parameters. An ANN model can predict the performance of diesel engine and the exhaust emissions with correlation coefficient (R2) in the range of 0.98-1. Mean Relative Errors (MRE) values are in the range of 0.46-5.8%, while the Mean Square Errors (MSE) are found to be very low. It is evident that the ANN models are reliable tools for the prediction of DI diesel engine performance and emissions. The test results show that the optimum NOP is 250 bar with B100.