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Meso-scale machining capabilities and issues

Description: Meso-scale manufacturing processes are bridging the gap between silicon-based MEMS processes and conventional miniature machining. These processes can fabricate two and three-dimensional parts having micron size features in traditional materials such as stainless steels, rare earth magnets, ceramics, and glass. Meso-scale processes that are currently available include, focused ion beam sputtering, micro-milling, micro-turning, excimer laser ablation, femto-second laser ablation, and micro electro discharge machining. These meso-scale processes employ subtractive machining technologies (i.e., material removal), unlike LIGA, which is an additive meso-scale process. Meso-scale processes have different material capabilities and machining performance specifications. Machining performance specifications of interest include minimum feature size, feature tolerance, feature location accuracy, surface finish, and material removal rate. Sandia National Laboratories is developing meso-scale electro-mechanical components, which require meso-scale parts that move relative to one another. The meso-scale parts fabricated by subtractive meso-scale manufacturing processes have unique tribology issues because of the variety of materials and the surface conditions produced by the different meso-scale manufacturing processes.
Date: May 15, 2000
Creator: BENAVIDES,GILBERT L.; ADAMS,DAVID P. & YANG,PIN
Partner: UNT Libraries Government Documents Department

Synthesis and optimization of integrated chemical processes

Description: This is the final technical report for the project titled ''Synthesis and optimization of integrated chemical processes''. Progress is reported on novel algorithms for the computation of all heteroazeotropic compositions present in complex liquid mixtures; the design of novel flexible azeotropic separation processes using middle vessel batch distillation columns; and theory and algorithms for sensitivity analysis and numerical optimization of hybrid discrete/continuous dynamic systems.
Date: April 26, 2002
Creator: Barton, Paul I. & Evans, Lawrence B.
Partner: UNT Libraries Government Documents Department

Characterizing the Effects of High Wind Penetration on a Small Isolated Grid in Arctic Alaska

Description: This paper examines the operating characteristics of the wind-diesel system in Kotzebue, Alaska, operated by Kotzebue Electric Association (KEA). KEA began incorporating wind power into its 100% diesel generating system in 1997 with three 66 kW wind turbines. In 1999, KEA added another seven 66 kW turbines, resulting in the current wind capacity of 660 kW. KEA is in the process of expanding its wind project again and ultimately expects to operate 2-3 MW of wind capacity. With a peak load of approximately 4 MW and a minimum load of approximately 1.6 MW, the wind penetration is significant. KEA is currently experiencing greater than 35% wind penetration, sometimes for several consecutive hours. This paper discusses the observed wind penetration at KEA and evaluates the effects of wind penetration on power quality on the KEA grid.
Date: July 18, 2001
Creator: Randall, G; Vilhauer, R. (Global Energy Concepts, LLC) & Thompson, C. (Thompson Engineering Company)
Partner: UNT Libraries Government Documents Department

A compendium of solar dish/Stirling technology

Description: This report surveys the emerging dish/Stirling technology. It documents -- using consistent terminology the design characteristics of dish concentrators, receivers, and Stirling engines applicable to solar electric power generation. Development status and operating experience for each system and an overview of dish/Stirling technology are also presented. This report enables comparisons of concentrator, receiver, and engine technologies. Specifications and performance data are presented on systems and on components that are in use or that could be used in dish/Stirling systems. This report is organized into two parts: The first part (Chapters 1 through 4) provides an overview of dish/Stirling technology -- the dish/ Stirling components (concentrator, receiver, and engine/alternator), current technology, basic theory, and technology development. The second part (Chapters 5 through 7) provides a detailed survey of the existing dish/Stirling concentrators, receivers, and engine/alternators.
Date: January 1, 1994
Creator: Stine, W. B. & Diver, R. B.
Partner: UNT Libraries Government Documents Department

Graduate Automotive Technology Education (GATE) Program: Center of Automotive Technology Excellence in Advanced Hybrid Vehicle Technology at West Virginia University

Description: This report summarizes the technical and educational achievements of the Graduate Automotive Technology Education (GATE) Center at West Virginia University (WVU), which was created to emphasize Advanced Hybrid Vehicle Technology. The Center has supported the graduate studies of 17 students in the Department of Mechanical and Aerospace Engineering and the Lane Department of Computer Science and Electrical Engineering. These students have addressed topics such as hybrid modeling, construction of a hybrid sport utility vehicle (in conjunction with the FutureTruck program), a MEMS-based sensor, on-board data acquisition for hybrid design optimization, linear engine design and engine emissions. Courses have been developed in Hybrid Vehicle Design, Mobile Source Powerplants, Advanced Vehicle Propulsion, Power Electronics for Automotive Applications and Sensors for Automotive Applications, and have been responsible for 396 hours of graduate student coursework. The GATE program also enhanced the WVU participation in the U.S. Department of Energy Student Design Competitions, in particular FutureTruck and Challenge X. The GATE support for hybrid vehicle technology enhanced understanding of hybrid vehicle design and testing at WVU and encouraged the development of a research agenda in heavy-duty hybrid vehicles. As a result, WVU has now completed three programs in hybrid transit bus emissions characterization, and WVU faculty are leading the Transportation Research Board effort to define life cycle costs for hybrid transit buses. Research and enrollment records show that approximately 100 graduate students have benefited substantially from the hybrid vehicle GATE program at WVU.
Date: December 31, 2006
Creator: Clark, Nigle N.
Partner: UNT Libraries Government Documents Department

Preliminary Scaling and controls Analysis of an FHR-HTSE System Idaho National Laboratory Summer 2013 Final Report

Description: For new nuclear reactor system designs to be approved by regulatory agencies like the Nuclear Regulatory Commission (NRC), the details of system operation must be validated with respect to standards of safety, control, and output. A scaled experiment that replicates certain properties of the system can be used to validate compliance with regulatory standards, while avoiding the prohibitive cost and labor required to develop a fully functional prototype system; therefore, designing such an experiment is of special interest to current efforts to develop hybrid energy systems (HES) that integrate small modular reactors (SMRs), renewable energy systems, and industrial process applications such as hydrogen production and desalination. In addition, a scaled experiment can be an economical method of analyzing the interconnections between HES components and understanding the time constants associated between inter-component energy and information flows. This report discusses the results of a preliminary scaling analysis done for the primary loop of a 300 MWth Fluoride-Salt-Cooled High Temperature Reactor (FHR) that is coupled with a High-Temperature Steam Electrolysis system (HTSE), as well as the basic control logic that governs the primary components and the necessary hardware to achieve optimal functionality. The scaled facility will be a 1 MWth system that uses Dowtherm A as the simulant fluid for Flibe (the coolant of choice for the primary loop of molten salt reactors), and can validate the heat transfer and steady-state operational requirements of the 300 MWth prototype. The scaled facility matches the Prandtl and Reynolds numbers associated with steady-state operation of the FHR-HTSE’s primary loop without having to deal with very high temperatures, flow rates, or power inputs. This will allow the facility to run experiments that analyze various thermophysical and fluid-dynamic properties that characterize reactor operation, such as pressure drops, radial temperature distribution, heat exchanger conditions. The facility also has potential ...
Date: August 1, 2013
Creator: Bragg-Sitton, Shannon; Sabharwall, Piyush & Upadhya, Rohit
Partner: UNT Libraries Government Documents Department

Preliminary Scaling and controls Analysis of an FHR-HTSE System Idaho National Laboratory Summer 2013 Final Report

Description: For new nuclear reactor system designs to be approved by regulatory agencies like the Nuclear Regulatory Commission (NRC), the details of system operation must be validated with respect to standards of safety, control, and output. A scaled experiment that replicates certain properties of the system can be used to validate compliance with regulatory standards, while avoiding the prohibitive cost and labor required to develop a fully functional prototype system; therefore, designing such an experiment is of special interest to current efforts to develop hybrid energy systems (HES) that integrate small modular reactors (SMRs), renewable energy systems, and industrial process applications such as hydrogen production and desalination. In addition, a scaled experiment can be an economical method of analyzing the interconnections between HES components and understanding the time constants associated between inter-component energy and information flows. This report discusses the results of a preliminary scaling analysis done for the primary loop of a 300 MWth Fluoride-Salt-Cooled High Temperature Reactor (FHR) that is coupled with a High-Temperature Steam Electrolysis system (HTSE), as well as the basic control logic that governs the primary components and the necessary hardware to achieve optimal functionality. The scaled facility will be a 1 MWth system that uses Dowtherm A as the simulant fluid for Flibe (the coolant of choice for the primary loop of molten salt reactors), and can validate the heat transfer and steady-state operational requirements of the 300 MWth prototype. The scaled facility matches the Prandtl and Reynolds numbers associated with steady-state operation of the FHR-HTSE’s primary loop without having to deal with very high temperatures, flow rates, or power inputs. This will allow the facility to run experiments that analyze various thermophysical and fluid-dynamic properties that characterize reactor operation, such as pressure drops, radial temperature distribution, heat exchanger conditions. The facility also has potential ...
Date: January 1, 2014
Creator: Bragg-Sitton, Shannon; Sabharwall, Piyush & Upadhya, Rohit
Partner: UNT Libraries Government Documents Department

Track reconstruction in the NAL 30-inch bubble chamber-wide gap spark chamber hybrid system

Description: The authors describe the track reconstruction and bubble chamber/spark chamber hookup software used in the NAL hybrid spectrometer. Results for 15-200 GeV/c tracks are presented. Further details of the physical characteristics of the hybrid system and preliminary physics results are presented in accompanying papers.
Date: January 1, 1973
Partner: UNT Libraries Government Documents Department

Multiple Correlations and High Tranverse Momentum Jets in 147-GeV/c pi- p Interactions

Description: We examine multiparticle correlations in a {pi}{sup -}p experiment at 147 GeV/c performed by the Proportional Hybrid System Consortium. The major aim of this paper is to demonstrate the existence of clusters in our data. We use different statistical algorithms to assemble into clusters the particles in each event which are associated by virtue of small relative angles. We find that these clusters are stable against different choices of metric and/or algorithm, and reproduce the effects previously observed in the data corresponding to clusters. Some of these clusters have properties similar to high p{sub T} jets. A detailed study of these jet-like clusters is described, and comparisons with some counter experiments are discussed.
Date: March 1, 1981
Creator: Brick, D.; Shapiro, A.M.; Widgoff, M.; U., /Brown; Alyea, E.D., Jr.; U., /Indiana et al.
Partner: UNT Libraries Government Documents Department

Hybrid MOSFET/Driver for Ultra-Fast Switching

Description: The ultra-fast switching of power MOSFETs, in about 1ns, is very challenging. This is largely due to the parasitic inductance that is intrinsic to commercial packages used for both MOSFETs and drivers. Parasitic gate and source inductance not only limit the voltage rise time on the MOSFET internal gate structure but can also cause the gate voltage to oscillate. This paper describes a hybrid approach that substantially reduces the parasitic inductance between the driver and MOSFET gate, as well as between the MOSFET source and its external connection. A flip chip assembly is used to directly attach a die-form power MOSFET and driver on a PCB. The parasitic inductances are significantly reduced by eliminating bond wires and minimizing lead length. The experimental results demonstrate ultra-fast switching of the power MOSFET with excellent control of the gate-source voltage.
Date: July 14, 2009
Creator: Tang, T
Partner: UNT Libraries Government Documents Department

The Hybrid Emulsion Detector for MINOS R&D Proposal

Description: The MINOS (Main Injector Neutrino Oscillation Search) experiment is designed to search for neutrino oscillations with a sensitivity significantly greater than has been achieved to date. The phenomenon of neutrino oscillations, whose existence has not been proven convincingly so far, allows neutrinos of one "flavor" (type) to slowly transform themselves into another flavor, and then back again to the original flavor, as they propagate through space or matter. The MINOS experiment is optimized to explore the region of neutrino oscillation "parameter space" suggested by previous investigations of atmospheric neutrinos: the Kamiokande, IMB, Super-Kamiokande and Soudan 2 experiments. The study of oscillations in this region with a neutrino beam from the Main Injector requires measurements of the beam after a very long flight path. This in turn requires an intense neutrino beam and a massive detector in order to have an adequate event rate at a great distance from the source. We propose to enhance significantly the physics capabilities of the MINOS experiment by the addition of a Hybrid Emulsion Detector at Soudan, capable of unambigous identification of the neutrino flavor. Recent developments in emulsion experiments make such a detector possible, although significant technological challenges must be overcome. We propose to initiate an R&D effort to identify major potential problems and to develop practical solutions to them. This proposal is meant to be a summary of the work we feel is needed before a credible conceptual design report can be produced. It summarizes both the tasks that need to be done and new incremental resources that are required to perform them. It is our expectation that various individual institutions (those currently in MINOS and others anticipating joining) will submit separate individual funding requests, to funding agencies in both US and abroad, to provide most of the resources listed in Chapter 5. ...
Date: April 1, 1999
Creator: Adamson, P.; Alexandrov, K. V.; Allison, W. W.M.; Alner, G. J.; Ambats, I.; Anderson, B. et al.
Partner: UNT Libraries Government Documents Department

Test of Proportional Wire Chambers in Hybrid Systems

Description: This is an agreement between the National Accelerator Laboratory and Professor I. Pless of MIT representing the experimenters to provide selected instrumentation for the beam to the 30-inch bubble chamber, and to use the hybrid chamber for an experiment. This document contains an enumeration of the major items needed for the proper execution of Experiment No. 154 as expressed in the proposal for the experiment, subsequent correspondence, and the draft agreement. This agreement covers phases I and II of the experiment. In Phase I the experimenters will design, construct and bring into operation a complete upstream proportional chamber system. This system will tag incident beam particles as to type by correlating the Cerenkov signals furnished by NAL with the proper incoming particle. In addition, the system will measure the position of the incident particle which passed through the momentum slit. The system will contain three proportional wire chambers (3 planes each) which will provide data suitable for defining the incident beam both as to position and angle. The experimenters will furnish the computer, magnetic tape units, programs, and all necessary readout and interface hardware. When the system is installed, debugged, documented and completely functional, it will be turned over to NAL to be operated as a general facility. Phase II of the experiment consists of an exposure of about 20,000 30-inch bubble chamber pictures ({approx}6 beam tracks per picture) correlated with data from a set of proportional wire chambers downstream from the chamber. The experimenters expect to demonstrate the utility of the proportional chamber spectrometer by attempting to analyze every event. They will do this before requesting a major exposure.
Date: June 23, 1971
Creator: Fong, D.G.; Shapiro, A.M.; Widgott, M.; U., /Brown; Ascoli, G.; Eisenstein, B. et al.
Partner: UNT Libraries Government Documents Department

DIRECT FUEL CELL/TURBINE POWER PLANT

Description: In this reporting period, a milestone was achieved by commencement of testing and operation of the sub-scale hybrid direct fuel cell/turbine (DFC/T{reg_sign}) power plant. The operation was initiated subsequent to the completion of the construction of the balance-of-plant (BOP) and implementation of process and control tests of the BOP for the subscale DFC/T hybrid system. The construction efforts consisted of finishing the power plant insulation and completion of the plant instrumentation including the wiring and tubing required for process measurement and control. The preparation work also included the development of procedures for facility shake down, conditioning and load testing of the fuel cell, integration of the microturbine, and fuel cell/gas turbine load tests. At conclusion of the construction, the process and control (PAC) tests of BOP, including the microturbine, were initiated.
Date: May 23, 2003
Creator: Ghezel-Ayagh, Hossein
Partner: UNT Libraries Government Documents Department

Stellarator-Spheromak

Description: A novel concept for magnetic plasma confinement, Stellarator-Spheromak (SSP), is proposed. Numerical analysis with the classical-stellarator-type outboard stellarator windings demonstrates a number of potential advantages of SSP for controlled nuclear fusion. Among the main ones are: simple and compact magnet coil configuration, absence of material structures (e.g. magnet coils or conducting walls) in the center of the torus, high rotational transform, and a possibility of MHD equilibria with very high {beta} (pressure/magnetic pressure) of the confined plasma.
Date: March 1, 1997
Creator: Moroz, P.E.
Partner: UNT Libraries Government Documents Department

Failure analysis for micro-electrical-mechanical systems (MEMS)

Description: Micro-Electrical Mechanical Systems (MEMS) is an emerging technology with demonstrated potential for a wide range of applications including sensors and actuators for medical, industrial, consumer, military, automotive and instrumentation products. Failure analysis (FA) of MEMS is critically needed for the successful design, fabrication, performance analysis and reliability assurance of this new technology. Many devices have been examined using techniques developed for integrated circuit analysis, including optical inspection, scanning laser microscopy (SLM), scanning electron microscopy (SEM), focused ion beam (FIB) techniques, atomic force microscopy (AFM), infrared (IR) microscopy, light emission (LE) microscopy, acoustic microscopy and acoustic emission analysis. For example, the FIB was used to microsection microengines that developed poor performance characteristics. Subsequent SEM analysis clearly demonstrated the absence of wear on gear, hub, and pin joint bearing surfaces, contrary to expectations. Another example involved the use of infrared microscopy for thermal analysis of operating microengines. Hot spots were located, which did not involve the gear or hub, but indicated contact between comb structures which drive microengines. Voltage contrast imaging proved useful on static and operating MEMS in both the SEM and the FIB and identified electrostatic clamping as a potentially significant contributor to failure mechanisms in microengines. This work describes MEMS devices, FA techniques, failure modes, and examples of FA of MEMS.
Date: October 1, 1997
Creator: Peterson, K.A.; Tangyunyong, P. & Barton, D.L.
Partner: UNT Libraries Government Documents Department

Energy storage for hybrid remote power systems

Description: Energy storage can be a cost-effective component of hybrid remote power systems. Storage serves the special role of taking advantage of intermittent renewable power sources. Traditionally this role has been played by lead-acid batteries, which have high life-cycle costs and pose special disposal problems. Hydrogen or zinc-air storage technologies can reduce life-cycle costs and environmental impacts. Using projected data for advanced energy storage technologies, LLNL ran an optimization for a hypothetical Arctic community with a reasonable wind resource (average wind speed 8 m/s). These simulations showed the life-cycle annualized cost of the total energy system (electric plus space heating) might be reduced by nearly 40% simply by adding wind power to the diesel system. An additional 20 to 40% of the wind-diesel cost might be saved by adding hydrogen storage or zinc-air fuel cells to the system. Hydrogen produced by electrolysis of water using intermittent, renewable power provides inexpensive long-term energy storage. Conversion back to electricity with fuel cells can be accomplished with available technology. The advantages of a hydrogen electrolysis/fuel cell system include low life-cycle costs for long term storage, no emissions of concern, quiet operation, high reliability with low maintenance, and flexibility to use hydrogen as a direct fuel (heating, transportation). Disadvantages include high capital costs, relatively low electrical turn-around efficiency, and lack of operating experience in utility settings. Zinc-air fuel cells can lower capital and life-cycle costs compared to hydrogen, with most of the same advantages. Like hydrogen systems, zinc-air technology promises a closed system for long-term storage of energy from intermittent sources. The turn around efficiency is expected to exceed 60%, while use of waste heat can potentially increase overall energy efficiency to over 80%.
Date: March 1, 1998
Creator: Isherwood, W.
Partner: UNT Libraries Government Documents Department

Failure modes in surface micromachined microelectromechanical actuators

Description: In order for the rapidly emerging field of MicroElectroMechanical Systems (MEMS) to meet its extraordinary expectations regarding commercial impact, issues pertaining to how they fail must be understood. The authors identify failure modes common to a broad range of MEMS actuators, including adhesion (stiction) and friction induced failures caused by improper operational methods, mechanical instabilities, and electrical instabilities. Demonstrated methods to mitigate these failure modes include implementing optimized designs, model based operational methods, and chemical surface treatments.
Date: March 1, 1998
Creator: Miller, S.L.; Rodgers, M.S.; LaVigne, G.; Sniegowski, J.J.; Clews, P.; Tanner, D.M. et al.
Partner: UNT Libraries Government Documents Department

Design, fabrication, and certification of advanced modular PV power systems. Final technical progress report

Description: Solar Electric Specialties Company (SES) has completed a two and a half year effort under the auspices of the US Department of Energy (DOE) PVMaT (Photovoltaic Manufacturing Technology) project. Under Phase 4A1 of the project for Product Driven System and Component Technology, the SES contract ``Design, Fabrication and Certification of Advanced Modular PV Power Systems`` had the goal to reduce installed system life cycle costs through development of certified (Underwriters Laboratories or other listing) and standardized prototype products for two of the product lines, MAPPS{trademark} (Modular Autonomous PV Power Supply) and Photogensets{trademark}. MAPPS are small DC systems consisting of Photovoltaic modules, batteries and a charge controller and producing up to about a thousand watt-hours per day. Photogensets are stand-alone AC systems incorporating a generator as backup for the PV in addition to a DC-AC inverter and battery charger. The program tasks for the two-year contract consisted of designing and fabricating prototypes of both a MAPPS and a Photogenset to meet agency listing requirements using modular concepts that would support development of families of products, submitting the prototypes for listing, and performing functionality testing at Sandia and NREL. Both prototypes were candidates for UL (Underwriters Laboratories) listing. The MAPPS was also a candidate for FM (Factory Mutual) approval for hazardous (incendiary gases) locations.
Date: October 1, 1998
Creator: Lambarski, T. & Minyard, G.
Partner: UNT Libraries Government Documents Department

Optimum flywheel sizing for parallel and series hybrid vehicles

Description: Flywheels have the possibility of providing high turnaround efficiency and high specific power output. These characteristics are very important for the successful manufacture of parallel and series hybrid vehicles, which have the potential for providing high fuel economy and very low emissions with range and performance comparable to today`s light-duty vehicles. Flywheels have a high specific power output, but relatively low specific energy output. Therefore, it is of importance to determine energy and power requirements for flywheels applied to light-duty vehicles. Vehicle applications that require an energy storage system with high power and low energy are likely to benefit from a flywheel. In this paper, a vehicle simulation code and a flywheel model are applied to the calculation of optimum flywheel energy storage capacity for a parallel and a series hybrid vehicle. A conventional vehicle is also evaluated as a base-case, to provide an indication of the fuel economy gains that can be obtained with flywheel hybrid vehicles. The results of the analysis indicate that the optimum flywheel energy storage capacity is relatively small. This results in a low weight unit that has a significant power output and high efficiency. Emissions generated by the hybrid vehicles are not calculated, but have the potential of being significantly lower than the emissions from the conventional car.
Date: December 20, 1996
Creator: Aceves, S.M. & Smith, J.R.
Partner: UNT Libraries Government Documents Department

Innovative confinement concepts workshop

Description: The Innovative Confinement Concepts Workshop occurred in California during the week preceding the Second Symposium on Current Trends in International Fusion Research. An informal report was made to the Second Symposium. A summary of the Workshop concluded that some very promising ideas were presented, that innovative concept development is a central element of the restructured US DOE. Fusion Energy Sciences program, and that the Workshop should promote real scientific progress in fusion.
Date: June 1, 1998
Creator: Kirkpatrick, R.C.
Partner: UNT Libraries Government Documents Department