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Effect of thin-film coating on wear in EGR-contaminated oil. (open access)

Effect of thin-film coating on wear in EGR-contaminated oil.

Increased use of higher-efficiency compression ignition direct injection (CIDI) diesel engines instead of today's gasoline engines will result in reduced fuel consumption and greenhouse gases emissions. However, NO{sub x} and particulate exhaust emissions from diesel engines must be significantly reduced due to their possible adverse health effects. Exhaust gas recirculation (EGR) is an effective way to reduce NO{sub x} emissions from diesel engines, but the particulates and acidic exhaust products in the recirculated gas will contaminate engine lubricant oil by increasing the soot content and total acid number (TAN). These factors will increase the wear rate in many critical engine components and seriously compromise engine durability. We have investigated the use of commercially available thin and hard coatings (TiN, TiCN, TiAlN, and CrN) to mitigate the negative effects of EGR on wear. In tests with the four-ball machine according to ASTM D4172, we found that all the four coatings deposited on M-50 steel significantly reduced wear in EGR-contaminated oils when compared with uncoated M50 steel balls.
Date: December 6, 2001
Creator: Ajayi, O. O.; Aldajah, S. H.; Erdemir, A. & Fenske, G. R.
System: The UNT Digital Library
Far-infrared absorption in Sb-doped Ge epilayers near the metal-insulator transition (open access)

Far-infrared absorption in Sb-doped Ge epilayers near the metal-insulator transition

None
Date: December 6, 2001
Creator: Bandaru, Jordana; Beeman, Jeffrey W. & Haller, Eugene E.
System: The UNT Digital Library
The history of LOCA embrittlement criteria. (open access)

The history of LOCA embrittlement criteria.

None
Date: December 6, 2001
Creator: Hache, G. & Chung, H.M.
System: The UNT Digital Library
Performance of amorphous carbon coating in turbocompressor air bearings. (open access)

Performance of amorphous carbon coating in turbocompressor air bearings.

None
Date: December 6, 2001
Creator: Ajayi, O. O.; Woodford, J. B.; Erdemir, A. & Fenske, G. R.
System: The UNT Digital Library
Structural basis of water specific transport through AQP1 water channel (open access)

Structural basis of water specific transport through AQP1 water channel

None
Date: December 6, 2001
Creator: Sui, Haixin; Han, Bong-Gyoon; Lee, John K.; Walian, Peter & Jap, Bing K.
System: The UNT Digital Library
Structure characteristics of ISD coated conductors. (open access)

Structure characteristics of ISD coated conductors.

None
Date: December 6, 2001
Creator: Tang, Y. L.; Miller, D. J.; Ma, B.; Koritala, R. E. & Balachandran, U.
System: The UNT Digital Library
Synchrotron radiation from electron beams in plasma focusing channels (open access)

Synchrotron radiation from electron beams in plasma focusing channels

Spontaneous radiation emitted from relativistic electrons undergoing betatron motion in a plasma focusing channel is analyzed and application to plasma wakefield accelerator experiments and to the ion channel laser (ICL) are discussed. Important similarities and differences between a free electron laser (FEL) and an ICL are delineated. It is shown that the frequency of spontaneous radiation is a strong function of the betatron strength parameter alpha-beta, which plays a similar role to that of the wiggler strength parameter in a conventional FEL. For alpha-beta > 1, radiation is emitted in numerous harmonics. Furthermore, alpha-beta is proportional to the amplitude of the betatron orbit, which varies for every electron in the beam. The radiation spectrum emitted from an electron beam is calculated by averaging the single electron spectrum over the electron distribution. This leads to a frequency broadening of the radiation spectrum, which places serious limits on the possibility of realizing an ICL.
Date: December 6, 2001
Creator: Esarey, E.; Shadwick, B. A.; Catravas, P. & Leemans, W. P.
System: The UNT Digital Library
ADVANCED STEAM GENERATORS (open access)

ADVANCED STEAM GENERATORS

Concerns about climate change have encouraged significant interest in concepts for ultra-low or ''zero''-emissions power generation systems. In some proposed concepts, nitrogen is removed from the combustion air and replaced with another diluent such as carbon dioxide or steam. In this way, formation of nitrogen oxides is prevented, and the exhaust stream can be separated into concentrated CO{sub 2} and steam or water streams. The concentrated CO{sub 2} stream could then serve as input to a CO{sub 2} sequestration process or utilized in some other way. Some of these concepts are illustrated in Figure 1. This project is an investigation of one approach to ''zero'' emission power generation. Oxy-fuel combustion is used with steam as diluent in a power cycle proposed by Clean Energy Systems, Inc. (CES) [1,2]. In oxy-fuel combustion, air separation is used to produce nearly pure oxygen for combustion. In this particular concept, the combustion temperatures are moderated by steam as a diluent. An advantage of this technique is that water in the product stream can be condensed with relative ease, leaving a pure CO{sub 2} stream suitable for sequestration. Because most of the atmospheric nitrogen has been separated from the oxidant, the potential to form any …
Date: November 6, 2001
Creator: Richards, George A.; Casleton, Kent H.; Lewis, Robie E.; Rogers, William A.; Woike, Mark R. & Willis, Brian P.
System: The UNT Digital Library
CHARACTERIZATION OF A RIGID BARRIER FILTER SYSTEM (open access)

CHARACTERIZATION OF A RIGID BARRIER FILTER SYSTEM

A mathematical model is formulated to describe the dynamics of a rigid barrier filter system. Complete with filtration, regeneration and particle re-deposition, this model provides sizing information for new filter systems and diagnostic information for operating filter systems. To turn this model into a practical and smart filter system predictive model, monitoring devices for variables such as real-time particle concentration and size distribution are currently under laboratory development. The program goal is to introduce a smart filter system to supervise its operation and to assure its system reliability. Primarily, a smart filter system will update operating information, sound up malfunction alarms, and provide self-activated measures such as adjusting the cleaning frequency, intensity and back-pulse duration.
Date: November 6, 2001
Creator: Chiang, Ta-Kuan
System: The UNT Digital Library
Circulating Fluid-Bed Technology for Advanced Power Systems (open access)

Circulating Fluid-Bed Technology for Advanced Power Systems

Circulating fluid bed technology offers the advantages of a plug flow, yet well-mixed, and high throughput reactor for power plant applications. The ability to effectively scale these systems in size, geometry, and operating conditions is limited because of the extensive deviation from ideal dilute gas-solids flow behavior (Monazam et al., 2001; Li, 1994). Two fluid computations show promise of accurately simulating the hydrodynamics in the riser circulating fluid bed; however, validation tests for large vessels with materials of interest to the power industry are lacking (Guenther et al., 2002). There is little available data in reactors large enough so that geometry (i.e. entrance, exit, and wall) effects do not dominate the hydrodynamics, yet with sufficiently large particle sizes to allow sufficiently large grid sizes to allow accurate and timely hydrodynamic simulations. To meet this need experimental tests were undertaken with relatively large particles of narrow size distribution in a large enough unit to reduce the contributions of wall effects and light enough to avoid geometry effects. While computational fluid dynamic calculations are capable of generating detailed velocity and density profiles, it is believed that the validation and model development begins with the ability to simulate the global flow regime transitions. …
Date: November 6, 2001
Creator: Shadle, Lawrence J.; Ludlow, J. Christopher; Mei, Joseph S. & Guenther, Christopher
System: The UNT Digital Library
COMPUTATIONAL FLUID DYNAMICS MODELING ANALYSIS OF COMBUSTORS (open access)

COMPUTATIONAL FLUID DYNAMICS MODELING ANALYSIS OF COMBUSTORS

In the current fiscal year FY01, several CFD simulations were conducted to investigate the effects of moisture in biomass/coal, particle injection locations, and flow parameters on carbon burnout and NO{sub x} inside a 150 MW GEEZER industrial boiler. Various simulations were designed to predict the suitability of biomass cofiring in coal combustors, and to explore the possibility of using biomass as a reburning fuel to reduce NO{sub x}. Some additional CFD simulations were also conducted on CERF combustor to examine the combustion characteristics of pulverized coal in enriched O{sub 2}/CO{sub 2} environments. Most of the CFD models available in the literature treat particles to be point masses with uniform temperature inside the particles. This isothermal condition may not be suitable for larger biomass particles. To this end, a stand alone program was developed from the first principles to account for heat conduction from the surface of the particle to its center. It is envisaged that the recently developed non-isothermal stand alone module will be integrated with the Fluent solver during next fiscal year to accurately predict the carbon burnout from larger biomass particles. Anisotropy in heat transfer in radial and axial will be explored using different conductivities in radial and …
Date: November 6, 2001
Creator: Mathur, M. P.; Freeman, Mark & Gera, Dinesh
System: The UNT Digital Library
A Computational Workbench Environment For Virtual Power Plant Simulation (open access)

A Computational Workbench Environment For Virtual Power Plant Simulation

In this paper we describe our progress toward creating a computational workbench for performing virtual simulations of Vision 21 power plants. The workbench provides a framework for incorporating a full complement of models, ranging from simple heat/mass balance reactor models that run in minutes to detailed models that can require several hours to execute. The workbench is being developed using the SCIRun software system. To leverage a broad range of visualization tools the OpenDX visualization package has been interfaced to the workbench. In Year One our efforts have focused on developing a prototype workbench for a conventional pulverized coal fired power plant. The prototype workbench uses a CFD model for the radiant furnace box and reactor models for downstream equipment. In Year Two and Year Three, the focus of the project will be on creating models for gasifier based systems and implementing these models into an improved workbench. In this paper we describe our work effort for Year One and outline our plans for future work. We discuss the models included in the prototype workbench and the software design issues that have been addressed to incorporate such a diverse range of models into a single software environment. In addition, we …
Date: November 6, 2001
Creator: Bockelie, Michael J.; Swensen, David A.; Denison, Martin K. & Sarofim, Adel F.
System: The UNT Digital Library
Development of Foster Wheeler's Vision 21 Partial Gasification Module (open access)

Development of Foster Wheeler's Vision 21 Partial Gasification Module

The US Department of Energy (DOE) has awarded Foster Wheeler Development Corporation a contract to develop a partial gasification module (PGM) that represents a critical element of several potential coal-fired Vision 21 plants. When utilized for electrical power generation, these plants will operate with efficiencies greater than 60% while producing near zero emissions of traditional stack gas pollutants. The new process partially gasifies coal at elevated pressure producing a coal derived syngas and a char residue. The syngas can be used to fuel the most advanced power producing equipment such as solid oxide fuel cells or gas turbines or processed to produce clean liquid fuels or chemicals for industrial users. The char residue is not wasted; it can also be used to generate electricity by fueling boilers that drive the most advanced ultra-supercritical pressure steam turbines. The unique aspect of the process is that it utilizes a pressurized circulating fluidized bed partial gasifier and does not attempt to consume the coal in a single step. To convert all the coal to syngas in a single step requires extremely high temperatures ({approx} 2500 to 2800F) that melt and vaporize the coal and essentially drive all coal ash contaminants into the syngas. …
Date: November 6, 2001
Creator: Robertson, A.
System: The UNT Digital Library
Durable Zinc Oxide-Based Regenerable Sorbents for Desulfurization of Syngas in a Fixed-Bed Reactor (open access)

Durable Zinc Oxide-Based Regenerable Sorbents for Desulfurization of Syngas in a Fixed-Bed Reactor

A fixed-bed regenerable desulfurization sorbent, identified as RVS-land developed by researchers at the U.S. Department of Energy's National Energy Technology Laboratory, was awarded the R&D 100 award in 2000 and is currently offered as a commercial product by Sued-Chemie Inc. An extensive testing program for this sorbent was undertaken which included tests at a wide range of temperatures, pressures and gas compositions both simulated and generated in an actual gasifier for sulfidation and regeneration. This testing has demonstrated that during these desulfurization tests, the RVS-1 sorbent maintained an effluent H2S concentration of <5 ppmv at temperatures from 260 to 600 C (500-1100 F) and pressures of 203-2026 kPa(2 to 20 atm) with a feed containing 1.2 vol% H{sub 2}S. The types of syngas tested ranged from an oxygen-blown Texaco gasifier to biomass-generated syngas. The RVS-1 sorbent has high crush strength and attrition resistance, which, unlike past sorbent formulations, does not decrease with extended testing at actual at operating conditions. The sulfur capacity of the sorbent is roughly 17 to 20 wt.% and also remains constant during extended testing (>25 cycles). In addition to H{sub 2}S, the RVS-1 sorbent has also demonstrated the ability to remove dimethyl sulfide and carbonyl sulfide …
Date: November 6, 2001
Creator: Siriwardane, Ranjani V.; Cicero, Daniel C. (U.S. Department of Energy, National Energy Technology Laboratory, Morgantown); Stiegel, Gary J.; Gupta, Raghubir P. (U.S. Department of Energy, National Energy Technology Laboratory, Pittsburgh) & Turk, Brian S. (Research Triangle Institute)
System: The UNT Digital Library
Fuel Cell/Turbine Ultra High Efficiency Power System (open access)

Fuel Cell/Turbine Ultra High Efficiency Power System

FuelCell Energy, INC. (FCE) is currently involved in the design of ultra high efficiency power plants under a cooperative agreement (DE-FC26-00NT40) managed by the National Energy Technology Laboratory (NETL) as part of the DOE's Vision 21 program. Under this project, FCE is developing a fuel cell/turbine hybrid system that integrates the atmospheric pressure Direct FuelCell{reg_sign} (DFC{reg_sign}) with an unfired Brayton cycle utilizing indirect heat recovery from the power plant. Features of the DFC/T{trademark} system include: high efficiency, minimal emissions, simplicity in design, direct reforming internal to the fuel cell, no pressurization of the fuel cell, independent operating pressure of the fuel cell and turbine, and potential cost competitiveness with existing combined cycle power plants at much smaller sizes. Objectives of the Vision 21 Program include developing power plants that will generate electricity with net efficiencies approaching 75 percent (with natural gas), while producing sulfur and nitrogen oxide emissions of less than 0.01 lb/million BTU. These goals are significant improvements over conventional power plants, which are 35-60 percent efficient and produce emissions of 0.07 to 0.3 lb/million BTU of sulfur and nitrogen oxides. The nitrogen oxide and sulfur emissions from the DFC/T system are anticipated to be better than the Vision …
Date: November 6, 2001
Creator: Hossein, Ghezel-Ayagh
System: The UNT Digital Library
Fuel Flexibility in Gasification (open access)

Fuel Flexibility in Gasification

In order to increase efficiencies of carbonizers, operation at high pressures is needed. In addition, waste biomass fuels of opportunity can be used to offset fossil fuel use. The National Energy Technology Laboratory (NETL) Fluidized Bed Gasifier/Combustor (FBG/C) was used to gasify coal and mixtures of coal and biomass (sawdust) at 425 psig. The purpose of the testing program was to generate steady state operating data for modeling efforts of carbonizers. A test program was completed with a matrix of parameters varied one at a time in order to avoid second order interactions. Variables were: coal feed rate, pressure, and varying mixtures of sawdust and coal types. Coal types were Montana Rosebud subbituminous and Pittsburgh No. 8 bituminous. The sawdust was sanding waste from a furniture manufacturer in upstate New York. Coal was sieved from -14 to +60 mesh and sawdust was sieved to -14 mesh. The FBG/C operates at a nominal 425 psig, but pressures can be lowered. For the tests reported it was operated as a jetting, fluidized bed, ash-agglomerating gasifier. Preheated air and steam are injected into the center of the bottom along with the solid feed that is conveyed with cool air. Fairly stable reactor internal …
Date: November 6, 2001
Creator: McLendon, T. Robert; Pineault, Richard L.; Richardson, Steven W.; Rockey, John M.; Beer, Stephen K. (U.S. DOE National Energy Technology Laboratory); Lui, Alain P. et al.
System: The UNT Digital Library
Fuel-Flexible Gasification-Combustion Technology for Production of Hydrogen and Sequestration-Ready Carbon Dioxide (open access)

Fuel-Flexible Gasification-Combustion Technology for Production of Hydrogen and Sequestration-Ready Carbon Dioxide

Electricity produced from hydrogen in fuel cells can be highly efficient relative to competing technologies and has the potential to be virtually pollution free. Thus, fuel cells may become an ideal solution to this nation's energy needs if one has a satisfactory process for producing hydrogen from available energy resources such as coal, and low-cost alternative feedstocks such as biomass. GE EER is developing an innovative fuel-flexible advanced gasification-combustion (AGC) technology for production of hydrogen for fuel cells or combustion turbines, and a separate stream of sequestration-ready CO2. The AGC module can be integrated into a number of Vision- 21 power systems. It offers increased energy efficiency relative to conventional gasification and combustion systems and near-zero pollution. The R&D on the AGC technology is being conducted under a Vision-21 award from the U.S. DOE NETL with co-funding from GE EER, Southern Illinois University at Carbondale (SIU-C), and the California Energy Commission (CEC). The AGC technology converts coal and air into three separate streams of pure hydrogen, sequestration-ready CO2, and high temperature/pressure oxygen-depleted air to produce electricity in a gas turbine. The three-year program integrates lab-, bench- and pilot-scale studies to demonstrate the AGC concept. Process and kinetic modeling studies as …
Date: November 6, 2001
Creator: Rizeq, George; West, Janice; Frydman, Arnaldo; Subia, Raul; Kumar, Ravi; Zamansky, Vladimir et al.
System: The UNT Digital Library
The Fuel Processing Research Facility - A Platform for the Conduct of Synthesis Gas Technology R&D (open access)

The Fuel Processing Research Facility - A Platform for the Conduct of Synthesis Gas Technology R&D

Vision 21 is the U. S. Department of Energy's initiative to deploy high efficiency, ultraclean co-production coal conversion power plants in the twenty-first century. These plants will consist of power and co-production modules, which are integrated to meet specific power and chemical markets. A variety of fuel gas processing technology issues involving gas separations, cleanup, gas-to-liquid fuels production and chemical synthesis, to mention a few, will be addressed by the program. The overall goal is to effectively eliminate, at competitive costs, environmental concerns associated with the use of fossil fuels for producing electricity and transportation fuels. The Fuel Processing Research Facility (FPRF) was developed as a fuel-flexible platform to address many of these technology needs. The facility utilizes a simplified syngas generator that is capable of producing 2,000 standard cubic feet per hour of 900 degree Celsius and 30 atmosphere synthesis gas that can be tailored to the gas composition of interest. It was built on a ''mid-scale'' level in an attempt to successfully branch the traditionally difficult scale-up from laboratory to pilot scale. When completed, the facility will provide a multi-faceted R&D area for the testing of fuel cells, gas separation technologies, and other gas processing unit operations.
Date: November 6, 2001
Creator: Monahan, Michael J.; Berry, David A.; Gardner, Todd H. & Lyons, K. David
System: The UNT Digital Library
Hot/Warm Gas Cleanup (open access)

Hot/Warm Gas Cleanup

Using regenerable sorbents and transport or fluid-bed contacting, the Gas Process Development Unit (GPDU) at NETL-Morgantown will be used to demonstrate the process feasibility of removing sulfur from coal gasification or other fuel gas streams at temperatures above dew point of the gas. This technology, also known as hot or warm gas desulfurization, is expected to remove sulfur to concentrations lower than conventional systems at comparable cost. The project was constructed under the U.S. Department of Energy (DOE) Integrated Gasification Combined Cycle (IGCC) power system program and is an ''enabling technology'' in the Vision 21 program. The GPDU was designed to be the smallest scale research and development facility capable of providing viable scale-up design data for new integrated transport or fluid-bed desulfurization processes. With the capability to test at process conditions representative of anticipated commercial applications in terms of temperatures, pressures, major compositions, velocities, and sorbent cycling, the unit is expected to generate important information on process control, configuration, and sorbent suitability. In this way, the GPDU fills a strategic role between past/current small-scale testing and large-scale demonstrations. A primary objective of the project is to gain insight into which reactor combination (i.e., both transport, both fluid bed, or …
Date: November 6, 2001
Creator: Bissett, Larry A.
System: The UNT Digital Library
Hydrogen Separation Membranes for Vision 21 Fossil Fuel Plants (open access)

Hydrogen Separation Membranes for Vision 21 Fossil Fuel Plants

Eltron Research and team members CoorsTek, McDermott Technology, Sued Chemie, Argonne National Laboratory, and Oak Ridge National Laboratory are developing an environmentally benign, inexpensive, and efficient method for separating hydrogen from gas mixtures produced during industrial processes, such as coal gasification. This objective is being pursued using dense membranes based in part on Eltron-patented ceramic materials with a demonstrated ability for proton and electron conduction. The technical goals are being addressed by modifying single-phase and composite membrane composition and microstructure to maximize proton and electron conductivity without loss of material stability. Ultimately, these materials must enable hydrogen separation at practical rates under ambient and high-pressure conditions, without deactivation in the presence of feedstream components such as carbon dioxide, water, and sulfur. This project was motivated by the Department of Energy (DOE) National Energy Technology Laboratory (NETL) Vision 21 initiative which seeks to economically eliminate environmental concerns associated with the use of fossil fuels. The proposed technology addresses the DOE Vision 21 initiative in two ways. First, this process offers a relatively inexpensive solution for pure hydrogen separation that can be easily incorporated into Vision 21 fossil fuel plants. Second, this process could reduce the cost of hydrogen, which is a …
Date: November 6, 2001
Creator: Roark, Shane E.; Mackay, Richard & Sammells, Anthony F.
System: The UNT Digital Library
ISO 14001 EMS VALUE PROPOSITION. (open access)

ISO 14001 EMS VALUE PROPOSITION.

The objective of this report is to identify business opportunities and value for Battelle Organizations to undertake IS0 14001 Environmental Management System Implementation and registration to the international standard as a corporate strategic initiative.
Date: November 6, 2001
Creator: BRIGGS,S.L.K.
System: The UNT Digital Library
Numerical Modeling of Left-Handed Metamaterials (open access)

Numerical Modeling of Left-Handed Metamaterials

The EIGER method of moments program with periodic Green's function was used to model a periodic array of strips and split-ring resonators. Left-handed propagation due to negative index of refraction is demonstrated in a frequency band. The effective material parameters versus frequency are extracted from the EIGER solution.
Date: November 6, 2001
Creator: Burke, G J; Champagne, N J & Sharpe, R M
System: The UNT Digital Library
Overview of NETL In-House Vision 21 Activities (open access)

Overview of NETL In-House Vision 21 Activities

The Office of Science and Technology at the National Energy Technology Laboratory, conducts research in support of Department of Energy's Fossil Energy Program. The research is funded through a variety of programs with each program focusing on a particular aspect of fossil energy. Since the Vision 21 Concept is based on the Advanced Power System Programs (Integrated Gasification Combined Cycle, Pressurized Fluid Bed, HIPPS, Advanced Turbine Systems, and Fuel Cells) it is not surprising that much of the research supports the Vision 21 Concept. The research is classified and presented according to ''enabling technologies'' and ''supporting technologies'' as defined by the Vision 21 Program. Enabling technology include fuel flexible gasification, fuel flexible combustion, hydrogen separation from fuel gas, advanced combustion systems, circulating fluid bed technology, and fuel cells. Supporting technologies include development of advanced materials, computer simulations, computation al fluid dynamics modeling, and advanced environmental control. An overview of Vision 21 related research is described, emphasizing recent accomplishments and capabilities.
Date: November 6, 2001
Creator: Wildman, David J.
System: The UNT Digital Library
Overview of the NETL Onsite Fuel Cell R&D Program (open access)

Overview of the NETL Onsite Fuel Cell R&D Program

Onsite fuel cell R&D at the National Energy Technology Laboratory (NETL) has been ongoing since the late 1990's. The objective of the onsite program is to support development efforts of the fuel cell technology-related product lines and conduct fundamental research of advanced fuel cell technology. Of special focus is NETL's new 10-yr, multimillion dollar development program call the Solid State Energy Conversion Alliance (SECA). This program is aimed at developing low-cost mass manufactured solid oxide fuel cell technology for a wide variety of applications. In addition to SECA, there are a variety of other products/programs at NETL that can be supported by the onsite R&D group. Vision 21 is one such program and is the U. S. Department of Energy's initiative to deploy high efficiency, ultra-clean co-production coal conversion power plants in the twenty-first century. These plants will consist of power and coproduction modules, which are integrated to meet specific power and chemical markets. In response to these program initiatives, NETL's onsite R&D group is developing significant capability and focusing current activity on the following areas: (1) High-Temperature Fuel Cell Test & Characterization; (2) Integrated Fuel Processing; (3) Fuel Cell Component and Systems Modeling; and (4) Sensors, Controls, and Instrumentation. …
Date: November 6, 2001
Creator: Berry, David A. & Gemmen, Randall S.
System: The UNT Digital Library