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3D Adaptive Mesh Refinement Simulations of Pellet Injection in Tokamaks (open access)

3D Adaptive Mesh Refinement Simulations of Pellet Injection in Tokamaks

We present results of Adaptive Mesh Refinement (AMR) simulations of the pellet injection process, a proven method of refueling tokamaks. AMR is a computationally efficient way to provide the resolution required to simulate realistic pellet sizes relative to device dimensions. The mathematical model comprises of single-fluid MHD equations with source terms in the continuity equation along with a pellet ablation rate model. The numerical method developed is an explicit unsplit upwinding treatment of the 8-wave formulation, coupled with a MAC projection method to enforce the solenoidal property of the magnetic field. The Chombo framework is used for AMR. The role of the E x B drift in mass redistribution during inside and outside pellet injections is emphasized.
Date: October 20, 2003
Creator: Samtaney, R.; Jardin, S. C.; Colella, P. & Martin, D. F.
Object Type: Report
System: The UNT Digital Library
78th Texas Legislature, Third Called Session, House Bill 24, Chapter 9 (open access)

78th Texas Legislature, Third Called Session, House Bill 24, Chapter 9

Bill introduced by the Texas House of Representatives relating to appropriations to departments and agencies of the state government, including conditions, limitations, rules, and procedures for allocating and expending appropriations.
Date: October 20, 2003
Creator: Texas. Legislature. House of Representatives.
Object Type: Legislative Document
System: The Portal to Texas History
78th Texas Legislature, Third Called Session, House Bill 28, Chapter 10 (open access)

78th Texas Legislature, Third Called Session, House Bill 28, Chapter 10

Bill introduced by the Texas House of Representatives relating to state and local government fiscal management, including various matters related to increasing administrative efficiency in state government; making related appropriations.
Date: October 20, 2003
Creator: Texas. Legislature. House of Representatives.
Object Type: Legislative Document
System: The Portal to Texas History
78th Texas Legislature, Third Called Session, House Bill 37, Chapter 11 (open access)

78th Texas Legislature, Third Called Session, House Bill 37, Chapter 11

Bill introduced by the Texas House of Representatives relating to contracts and grant programs related to the Texas Emissions Reduction Plan; making appropriations.
Date: October 20, 2003
Creator: Texas. Legislature. House of Representatives.
Object Type: Legislative Document
System: The Portal to Texas History
Adaptive low mach number simulations of a premixed turbulent laboratory burner (open access)

Adaptive low mach number simulations of a premixed turbulent laboratory burner

A parallel adaptive low Mach number model is used to study an experimental lean premixed turbulent methane V-flame that is stabilized on a rod spanning the exit plane of a circular nozzle. The fuel is turbulent due to an upstream perforated-plate, and the resulting flame extends downstream of the rod. We present three-dimensional time-dependent simulations of this configuration. The computations incorporate detailed reaction chemistry and transport using a dynamically adaptive block-structured grid algorithm and a time-split integration procedure. Flow field and flame surface statistics are gathered from the experiment and are compared to the computed results.
Date: October 20, 2003
Creator: Day, M.S.; Bell, J.B.; Lijewski, M.J.; Johnson, M.; Cheng, R.K. & Shepherd, I.G.
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 105, No. 185, Ed. 1 Monday, October 20, 2003 (open access)

Altus Times (Altus, Okla.), Vol. 105, No. 185, Ed. 1 Monday, October 20, 2003

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: October 20, 2003
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 112, No. 80, Ed. 1 Monday, October 20, 2003 (open access)

The Alvin Sun (Alvin, Tex.), Vol. 112, No. 80, Ed. 1 Monday, October 20, 2003

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: October 20, 2003
Creator: Schwind, Jim & Holton, Kathleen
Object Type: Newspaper
System: The Portal to Texas History
An Assessment of Energy-Related Career Paths of Senior Industrial Assessment Center Program Alumni (open access)

An Assessment of Energy-Related Career Paths of Senior Industrial Assessment Center Program Alumni

The purpose of this study was to assess the career paths of alumni from the U.S. Department of Energy's Industrial Assessment Center (IAC) program. IAC was originally named the Energy Analysis and Diagnostic Center (EADC) program when it began in association with four schools in 1976. The current IAC program provides funding to 26 engineering colleges, located in centers across the United States, to conduct energy, waste, and productivity assessments for small- to medium-sized manufacturing establishments within their respective regions. Through part-time employment with the university, students receive training and in turn conduct assessments for local manufacturers, under the direct supervision of engineering faculty. Annually, IAC participants conduct over 700 assessments, and each assessment generates recommendations for energy savings, energy cost savings, and waste and productivity cost savings customized for individual clients. An earlier study determined that energy savings could be attributed to alumni of the IAC program who take their IAC experiences with them to the professional workplace. During their careers, the alumni conduct additional energy assessments as well as influence energy efficiency through design, teaching and training, and other activities. Indeed, a significant level of program benefits can be attributed to the alumni. This project addressed such specific …
Date: October 20, 2003
Creator: Martin, M.A.
Object Type: Report
System: The UNT Digital Library
Autonomous Control of Nuclear Power Plants (open access)

Autonomous Control of Nuclear Power Plants

A nuclear reactor is a complex system that requires highly sophisticated controllers to ensure that desired performance and safety can be achieved and maintained during its operations. Higher-demanding operational requirements such as reliability, lower environmental impacts, and improved performance under adverse conditions in nuclear power plants, coupled with the complexity and uncertainty of the models, necessitate the use of an increased level of autonomy in the control methods. In the opinion of many researchers, the tasks involved during nuclear reactor design and operation (e.g., design optimization, transient diagnosis, and core reload optimization) involve important human cognition and decisions that may be more easily achieved with intelligent methods such as expert systems, fuzzy logic, neural networks, and genetic algorithms. Many experts in the field of control systems share the idea that a higher degree of autonomy in control of complex systems such as nuclear plants is more easily achievable through the integration of conventional control systems and the intelligent components. Researchers have investigated the feasibility of the integration of fuzzy logic, neural networks, genetic algorithms, and expert systems with the conventional control methods to achieve higher degrees of autonomy in different aspects of reactor operations such as reactor startup, shutdown in …
Date: October 20, 2003
Creator: Basher, H.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 81, No. 326, Ed. 1 Monday, October 20, 2003 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 81, No. 326, Ed. 1 Monday, October 20, 2003

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: October 20, 2003
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS (open access)

BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

The principal objective of this project is to develop materials technology for use in ultrasupercritical (USC) plant boilers capable of operating with 760 C (1400 F), 35 MPa (5000 psi) steam. This project has established a government/industry consortium to undertake a five-year effort to evaluate and develop of advanced materials that allow the use of advanced steam cycles in coal-based power plants. These advanced cycles, with steam temperatures up to 760 C, will increase the efficiency of coal-fired boilers from an average of 35% efficiency (current domestic fleet) to 47% (HHV). This efficiency increase will enable coal-fired power plants to generate electricity at competitive rates (irrespective of fuel costs) while reducing CO{sub 2} and other fuel-related emissions by as much as 29%. Success in achieving these objectives will support a number of broader goals. First, from a national prospective, the program will identify advanced materials that will make it possible to maintain a cost-competitive, environmentally acceptable coal-based electric generation option. High sulfur coals will specifically benefit in this respect by having these advanced materials evaluated in high-sulfur coal firing conditions and from the significant reductions in waste generation inherent in the increased operational efficiency. Second, from a national prospective, the …
Date: October 20, 2003
Creator: Viswanathan, R.; Coleman, K.; Swindeman, R.W.; Sarver, J.; Blough, J.; Mohn, W. et al.
Object Type: Report
System: The UNT Digital Library
Centrales au gaz et Energies renouvelables: comparer des pommes avec des pommes (open access)

Centrales au gaz et Energies renouvelables: comparer des pommes avec des pommes

The fundamental conclusion that we draw from this analysis is that one should not to base itself blindly on forecasts prices of natural gas when one compare contracts at price fixes with producers of renewable energy with contracts at variable prices with promoters power stations with gas. Indeed, forecasts of the prices of gas do not succeed not to enter the associated costs with the covering of the risk, that they are connected to the negative pressure against the cover, with the CAPM, with costs of transaction or with unspecified combination of three. Thus, insofar as price stability to length term is developed, better way of comparing the two choices would be to have recourse to the data on the prices in the long term natural gas, and not with forecasts of the prices. During three last years at least, the use of these prices in the long term would have besides license to correct a methodological error who, obviously, seem to have supported unduly, and of relatively important way, power stations with natural gas compared to their competitors of renewable energies.
Date: October 20, 2003
Creator: Bolinger, Mark; Wiser, Ryan & Golove, William
Object Type: Report
System: The UNT Digital Library
Coil Tolerance Impact on Plasma Surface Quality for NCSX (open access)

Coil Tolerance Impact on Plasma Surface Quality for NCSX

The successful operation of the National Compact Stellarator Experiment (NCSX) machine will require producing plasma configurations with good flux surfaces, with a minimum volume of the plasma lost to magnetic islands or stochastic regions. The project goal is to achieve good flux surfaces over 90% of the plasma volume. NCSX is a three period device designed to be operated with iota ranging from {approx}0.4 on axis to {approx}0.7 at the edge. The field errors of most concern are those that are resonant with 3/5 and 3/6 modes (for symmetry preserving field errors) and the 1/2 and 2/3 modes (for symmetry breaking field errors). In addition to losses inherent in the physics configuration itself, there will be losses from field errors arising from coil construction and assembly errors. Some of these losses can be recovered through the use of trim coils or correction coils. The impact of coil tolerances on plasma surface quality is evaluated herein for the NCSX design. The methods used in this evaluation are discussed. The ability of the NCSX trim coils to correct for field errors is also examined. The results are used to set coils tolerances for the various coil systems.
Date: October 20, 2003
Creator: Brooks, Art & Reiersen, Wayne
Object Type: Report
System: The UNT Digital Library
A Compact Quasi-axisymmetric Stellarator Reactor (open access)

A Compact Quasi-axisymmetric Stellarator Reactor

We report the progress made in assessing the potential of compact, quasi-axisymmetric stellarators as power-producing reactors. Using an aspect ratio A=4.5 configuration derived from NCSX and optimized with respect to the quasi-axisymmetry and MHD stability in the linear regime as an example, we show that a reactor of 1 GW(e) maybe realizable with a major radius *8 m. This is significantly smaller than the designs of stellarator reactors attempted before. We further show the design of modular coils and discuss the optimization of coil aspect ratios in order to accommodate the blanket for tritium breeding and radiation shielding for coil protection. In addition, we discuss the effects of coil aspect ratio on the peak magnetic field in the coils.
Date: October 20, 2003
Creator: Ku, L. P.
Object Type: Report
System: The UNT Digital Library
Dallas Representative Huelon Harrison Named Chairman of DART Board of Directors (open access)

Dallas Representative Huelon Harrison Named Chairman of DART Board of Directors

News release concerning the election of several DART board members to leadership possessions, including Huelon Harrison as board chairman.
Date: October 20, 2003
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Demonstration of Black Liquor Gasification at Big Island (open access)

Demonstration of Black Liquor Gasification at Big Island

This Technical Progress Report provides an account of the status of the project for the demonstration of Black Liquor Gasification at Georgia-Pacific Corporation's Big Island, VA facility. The report also includes budget information and a milestone schedule. The project to be conducted by G-P is a comprehensive, complete commercial-scale demonstration that is divided into two phases. Phase I is the validation of the project scope and cost estimate. Phase II is project execution, data acquisition and reporting, and consists of procurement of major equipment, construction and start-up of the new system. Phase II also includes operation of the system for a period of time to demonstrate the safe operation and full integration of the energy and chemical recovery systems in a commercial environment. The objective of Phase I is to validate the process design and to engineer viable solutions to any technology gaps. This phase includes engineering and planning for the integration of the full-scale MTCI/StoneChem PulseEnhanced{trademark} black liquor steam-reformer chemical recovery system into G-P's operating pulp and paper mill at Big Island, Virginia. During this phase, the scope and cost estimate will be finalized to confirm the cost of the project and its integration into the existing system at …
Date: October 20, 2003
Creator: DeCarrera, Robert
Object Type: Report
System: The UNT Digital Library
Effect of Anode Dielectric Coating on Hall Thruster Operation (open access)

Effect of Anode Dielectric Coating on Hall Thruster Operation

An interesting phenomenon observed in the near-anode region of a Hall thruster is that the anode fall changes from positive to negative upon removal of the dielectric coating, which is produced on the anode surface during the normal course of Hall thruster operation. The anode fall might affect the thruster lifetime and acceleration efficiency. The effect of the anode coating on the anode fall is studied experimentally using both biased and emissive probes. Measurements of discharge current oscillations indicate that thruster operation is more stable with the coated anode.
Date: October 20, 2003
Creator: Dorf, L.; Raitses, Y.; Fisch, N. J. & Semenov, V.
Object Type: Report
System: The UNT Digital Library
Electromagnetic Weibel Instability in Intense Charged Particle Beams with Large Energy Anisotropy (open access)

Electromagnetic Weibel Instability in Intense Charged Particle Beams with Large Energy Anisotropy

In plasmas with strongly anisotropic distribution functions, collective instabilities may develop if there is sufficient coupling between the transverse and longitudinal degrees of freedom. Our previous numerical and theoretical studies of intense charged particle beams with large temperature anisotropy [E. A. Startsev, R. C. Davidson and H. Qin, PRSTAB, 6, 084401 (2003); Phys. Plasmas 9, 3138 (2002)] demonstrated that a fast, electrostatic, Harris-like instability develops, and saturates nonlinearly, for sufficiently large temperature anisotropy (T{sub {perpendicular}b}/T{sub {parallel}b} >> 1). The total distribution function after saturation, however, is still far from equipartitioned. In this paper the linearized Vlasov-Maxwell equations are used to investigate detailed properties of the transverse electromagnetic Weibel-type instability for a long charge bunch propagating through a cylindrical pipe of radius r{sub w}. The kinetic stability analysis is carried out for azimuthally symmetric perturbations about a two-temperature thermal equilibrium distribution in the smooth-focusing approximation. The most unstable modes are identified, and their eigenfrequencies, radial mode structure and instability thresholds are determined. The stability analysis shows that, although there is free energy available to drive the electromagnetic Weibel instability, the finite transverse geometry of the charged particle beam introduces a large threshold value for the temperature anisotropy ((T{sub {perpendicular}b}/T{sub {parallel}b}){sup Weibel} …
Date: October 20, 2003
Creator: Startsev, Edward A. & Davidson, Ronald C.
Object Type: Report
System: The UNT Digital Library
Experimental and Numerical Investigation of Impinging Jet Flow in Square Ducts Intersecting at 90 Degrees (open access)

Experimental and Numerical Investigation of Impinging Jet Flow in Square Ducts Intersecting at 90 Degrees

An experimental and numerical investigation has been conducted on flow through two square ducts with a 2:1 hydraulic diameter ratio joined at a right angle. Measurements of the velocity field were acquired using a laser Doppler velocimeter at various planar locations throughout the ducts at a nominal Reynolds number of 68,000. Pressure drop measurements were taken for 3 Reynolds numbers between 46,000 and 93,000. Computational fluid dynamics (CFD) analyses were performed using STAR-CD to determine how well the experimental data could be predicted using the k-{var_epsilon}, k-{var_epsilon} RNG, k-{var_epsilon}Chen, k-{var_epsilon} quadratic, k-{omega}, and Spalart-Allmaras models. The results show that there are distinct differences in the CDF results. The standard k-{var_epsilon} model overpredicted the loss coefficient by 4% and underpredicted the exit swirl magnitude by 43%. The best predictor of the swirl decay was found to be the k-{omega} model, which adequately followed the data throughout the entire geometry and underpredicted the exit swirl by 16%. The best overall model was found to be Spalart-Allmaras, which overpredicted the loss coefficient by 2% and underpredicted the exit swirl magnitude by 40%.
Date: October 20, 2003
Creator: Corson, David & Vassallo, Peter
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, October 20, 2003 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, October 20, 2003

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: October 20, 2003
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
[Funeral Program for James Earl Waiters, October 20, 2003] (open access)

[Funeral Program for James Earl Waiters, October 20, 2003]

Funeral program for James Earl Waiters, born January 26, 1954 and died October 13, 2003. The funeral was held October 20, 2003 at St. Paul United Methodist Church, officiated by Rev. Terrence K. Hayes. Funeral arrangements were made through Lewis Funeral Home, and he was buried in Meadowlawn Memorial Park in San Antonio, Texas.
Date: October 20, 2003
Creator: unknown
Object Type: Pamphlet
System: The Portal to Texas History
Government Printing Office: Advancing GPO's Transformation Effort through Strategic Human Capital Management (open access)

Government Printing Office: Advancing GPO's Transformation Effort through Strategic Human Capital Management

A letter report issued by the General Accounting Office with an abstract that begins "The Government Printing Office (GPO) has undertaken the task of transforming itself in response to pressing fiscal and other realities in the 21st century. This report focuses on actions GPO's leaders can take to advance its transformation efforts through strategic human capital management and is a part of GAO's response to a congressional request that GAO conduct a general management review of GPO that focuses on issues related to GPO's management and transformation. GAO plans to address other management topics, including strategic planning and financial management, in a series of reports that may assist GPO in its ongoing transformation efforts."
Date: October 20, 2003
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Implementations of mesh refinement schemes for particle-in-cell plasma simulations (open access)

Implementations of mesh refinement schemes for particle-in-cell plasma simulations

Plasma simulations are often rendered challenging by the disparity of scales in time and in space which must be resolved. When these disparities are in distinctive zones of the simulation region, a method which has proven to be effective in other areas (e.g. fluid dynamics simulations) is the mesh refinement technique. We briefly discuss the challenges posed by coupling this technique with plasma Particle-In-Cell simulations and present two implementations in more detail, with examples.
Date: October 20, 2003
Creator: Vay, J. L.; Colella, P.; Friedman, A.; Grote, D. P.; McCorquodale, P. & Serafini, D. B.
Object Type: Article
System: The UNT Digital Library
Iraq: Summary of U.S. Casualties (open access)

Iraq: Summary of U.S. Casualties

None
Date: October 20, 2003
Creator: unknown
Object Type: Report
System: The UNT Digital Library