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2-D Simulations of Drainage Winds and Diffusion Compared to Observations

Description: A vertically integrated dynamical drainage flow model is developed from conservation equations for momentum and mass in a terrain-following coordinate system. Wind fields from the dynamical model drive a Monte Carlo transport and diffusion model. The model needs only topographic data, an Eulerian or Lagrangian time scale and a surface drag coefficient for input data, and can be started with a motionless atmosphere. Model wind and diffusion predictions are compared to observations from the rugge… more
Date: May 29, 2001
Creator: Garrett, A. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A 2-Megawatt load for testing high voltage dc power supplies

Description: A high power water-cooled resistive load, capable of dissipating 2 Megawatts at 95 kilovolts is being designed and built. The load utilizes wirewound resistor elements suspended inside insulating tubing contained within a pressure vessel which is supplied a continuous flow of deionized water for coolant. A sub-system of the load is composed of non-inductive resistor elements in an oil tank. Power tests conducted on various resistor types indicate that dissipation levels as high as 22 times the … more
Date: June 1, 1993
Creator: Horan, D.; Kustom, R.; Ferguson, M. & Primdahl, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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3-D turbulent particle dispersion submodel development. Quarterly progress report No. 1, 5 April--5 July 1991

Description: The lack of a mathematical description of the interactions of fluid turbulence with other physics-chemical processes is a major obstacle in modeling many industrial program. Turbulent two-phase flow is a phenomenon that is of significant practical importance to coal combustion as well as other disciplines. The interactions of fluid turbulence with the particulate phase has yet to be accurately and efficiently modeled for these industrial applications. On 15 May 1991 work was initiated to cover … more
Date: December 31, 1991
Creator: Smith, P. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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3-D turbulent particle dispersion submodel development. Quarterly progress report No. 2, 15 July--15 October 1991

Description: The lack of a mathematical description of the interactions of fluid turbulence with other physics-chemical processes is a major obstacle in modeling many industrial program. Turbulent two-phase flow is a phenomenon that is of significant practical importance to coal combustion as well as other disciplines. The interactions of fluid turbulence with the particulate phase has yet to be accurately and efficiently modeled for these industrial applications. On 15 May 1991 work was initiated to cover … more
Date: December 31, 1991
Creator: Smith, P. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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3-D Turbulent Particle Dispersion Submodel Development. Quarterly Progress Report No. 3, October 15, 1991--January 15, 1992

Description: Many practical combustion processes which use solid particles, liquid droplets, or slurries as fuels introduce these fuels into turbulent environments. Examples include spray combustion, pulverized coal and coal slurry combustion, fluidized beds, sorbent injection, and hazardous waste incineration. The interactions of the condensed phases with turbulent environments have not been well described. Such a description is complicated by the difficulty of describing turbulence in general, even in the… more
Date: September 1, 1994
Creator: Smith, P. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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3-D turbulent particle dispersion submodel development. Quarterly progress report No. 4, January 15, 1992--April 15, 1992

Description: Many practical combustion processes which use solid particles, liquid droplets, or slurries as fuels introduce these fuels into turbulent environments. Examples include spray combustion, pulverized coal and coal slurry combustion, fluidized beds, sorbent injection, and hazardous waste incineration. The interactions of the condensed phases with turbulent environments have not been well described. Such a description is complicated by the difficulty of describing turbulence in general, even in the… more
Date: September 1, 1994
Creator: Smith, P. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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1979 CECAM workshop on transport of fast electrons in laser fusion plasmas. Progress report

Description: Attention is given to three problem areas in laser-driven electron transport: (1) ion-acoustic turbulence as a source of inhibition, (2) the effects of anti E times anti j heating of the thermals, and (3) the possibility of thermal inhibition by thermal electron runaway or trapping.
Date: January 1, 1979
Creator: Mason, R.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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6th International Special Session on Current Trends in Numerical Simulation for Parallel Engineering Environments

Description: In today's world, the use of parallel programming and architectures is essential for simulating practical problems in engineering and related disciplines. Remarkable progress in CPU architecture (multi- and many-core, SMT, transactional memory, virtualization support, etc.), system scalability, and interconnect technology continues to provide new opportunities, as well as new challenges for both system architects and software developers. These trends are paralleled by progress in parallel algor… more
Date: July 9, 2007
Creator: Schulz, M & Trinitis, C
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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8th International Symposium on Transport Phenomena in Combustion

Description: The 8th International Symposium on Transport Phenomena in Combustion will be held in San Francisco, California, U.S.A., July 16-20, 1995, under the auspices of the Pacific Center of Thermal-Fluids Engineering. The purpose of the Symposium is to provide a forum for researchers and practitioners from around the world to present new developments and discuss the state of the art and future directions and priorities in the areas of transport phenomena in combustion. The Symposium is the eighth in a … more
Date: December 31, 1995
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Acceleration of hydrogen ions and conic formation along auroral field lines

Description: Electrostatic ion cyclotron turbulence and the formation of ion conics at low altitudes (approx. = 1500 km) along auroral field lines have been investigated analytically and by plasma numerical simulations. Ion cyclotron waves are assumed to be driven unstable by the up-going cold ionospheric electrons associated with the downward auroral current. When the electron drift speed is comparable to the electron thermal speed, it is found that the large amplitude, e phi/T/sub e/ approx. = 1, coherent… more
Date: May 1, 1982
Creator: Okuda, H. & Ashour-Abdalla, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Accurate Measure by Weight of Liquids in Industry

Description: This research's focus was to build a prototype of a computerized liquid dispensing system. This liquid metering system is based on the concept of altering the representative volume to account for temperature changes in the liquid to be dispensed. This is actualized by using a measuring tank and a temperature compensating displacement plunger. By constantly monitoring the temperature of the liquid, the plunger can be used to increase or decrease the specified volume to more accurately dispense l… more
Date: December 12, 1992
Creator: Muller, M.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Accurate Measure by Weight of Liquids in Industry. Final Report

Description: This research`s focus was to build a prototype of a computerized liquid dispensing system. This liquid metering system is based on the concept of altering the representative volume to account for temperature changes in the liquid to be dispensed. This is actualized by using a measuring tank and a temperature compensating displacement plunger. By constantly monitoring the temperature of the liquid, the plunger can be used to increase or decrease the specified volume to more accurately dispense l… more
Date: December 12, 1992
Creator: Muller, M. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Acoustic agglomeration of power plant fly ash. Final report

Description: The work has shown that acoustic agglomeration at practical acoustic intensities and frequencies is technically and most likely economically viable. The following studies were performed with the listed results: The physics of acoustic agglomeration is complex particularly at the needed high acoustic intensities in the range of 150 to 160 dB and frequencies in the 2500 Hz range. The analytical model which we developed, although not including nonlinear acoustic efforts, agreed with the trends obs… more
Date: January 1, 1982
Creator: Reethof, G. & McDaniel, O.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Acoustic and turbulent agglomeration of sodium aerosols. Quarterly report, January 1, 1977--March 31, 1977

Description: Tests of turbulent and acoustic agglomeration of captive sodium fire aerosols at concentrations of 0.1 to 20 gm/m/sup 3/ were conducted in 90 m/sup 3/ and 0.65 m/sup 3/ vessels to evaluate these mechanisms for direct application air cleaning systems. Aerosol mass concentration decay with time was monitored by sequential filter samples. Turbulence was generated mechanically with a 51 cm diameter centrifugal fan impeller and a reverberant acoustic field was created with an electronic siren. The e… more
Date: April 1, 1977
Creator: Hinds, W.; Mallove, E. F. & First, M. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Acoustic detection of momentum transfer during the abrupt transition from a laminar to a turbulent atmospheric boundary layer

Description: Acoustic sounder measurements of a vertical profile of the abrupt transition from a laminar to a turbulent atmospheric boundary layer were compared with meteorological measurements made at 10 m and 137 m on an instrumented tower. Sounder data show that conditions necessary for onset of the momentum burst phenomenon exist sometime during a clear afternoon when heat flux changes sign and the planetary surface cools. Under these conditions, the lowest part of the atmospheric boundary layer becomes… more
Date: January 1, 1975
Creator: Schubert, J. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Active Control for Statistically Stationary Turbulent PremixedFlame Simulations

Description: The speed of propagation of a premixed turbulent flame correlates with the intensity of the turbulence encountered by the flame. One consequence of this property is that premixed flames in both laboratory experiments and practical combustors require some type of stabilization mechanism to prevent blow-off and flashback. The stabilization devices often introduce a level of geometric complexity that is prohibitive for detailed computational studies of turbulent flame dynamics. Furthermore, the st… more
Date: August 30, 2005
Creator: Bell, J. B.; Day, M. S.; Grcar, J. F. & Lijewski, M. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Active control for turbulent premixed flame simulations

Description: Many turbulent premixed flames of practical interest are statistically stationary. They occur in combustors that have anchoring mechanisms to prevent blow-off and flashback. The stabilization devices often introduce a level of geometric complexity that is prohibitive for detailed computational studies of turbulent flame dynamics. As a result, typical detailed simulations are performed in simplified model configurations such as decaying isotropic turbulence or inflowing turbulence. In these conf… more
Date: March 26, 2004
Creator: Bell, John B.; Day, Marcus S.; Grcar, Joseph F. & Lijewski, Michael J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Active probing of plasma edge turbulence and feedback studies on the Texas Experimental Tokamak (TEXT)

Description: The edge fluctuations play a critical role in the overall tokamak confinement. Experiments on TEXT show that electrostatic fluctuations in the edge plasma are the dominant mechanism for energy and particle transport. The basic mechanisms responsible for the edge turbulence are the subject of ongoing research in fusion devices. To understand the driving forces responsible for edge fluctuations, a novel experiment is underway on TEXT to actively modify the turbulence at the plasma edge by launchi… more
Date: June 1, 1993
Creator: Uckan, T.; Carreras, B. A.; Richards, B.; Bengtson, R. D.; Crockett, D. B.; Gentle, K. W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Active probing of plasma edge turbulence and feedback studies on the Texas Experimental Tokamak (TEXT)

Description: A novel experiment is under way on the Texas Experimental Tokamak (TEXT) to actively modify the turbulence at the plasma edge by launching waves using electrostatic probes in the shadow of the limiter. The experiments are carried out with a wave launching system consisting of two Langmuir probes, which are about 1.8 cm apart in the poloidal direction, with respect to the magnetic field. These probes are operated in the electron side of the (I,V) characteristic. The probe tips are fed separately… more
Date: August 1, 1993
Creator: Uckan, T.; Richards, B. & Bengtson, R. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Adaptive compensation of atmospheric turbulence utilizing an interferometric wave-front sensor and a high-resolution MEMS-based spatial light modulator

Description: Horizontal path correction of optical beam propagation presents a severe challenge to adaptive optics systems due to the short transverse coherence length and the high degree of scintillation incurred by propagation along these paths. The system presented operates with nearly monochromatic light. It does not require a global reconstruction of the phase, thereby eliminating issues with branch points and making its performance relatively unaffected by scintillation. The systems pixel count, 1024,… more
Date: August 12, 2004
Creator: Baker, K.; Stappaerts, E.; Gavel, D.; Tucker, J.; Silva, D.; Wilks, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Adaptive optics instrument for long-range imaging. Final report

Description: The science and history of imaging through a turbulent atmosphere is reviewed in detail. Traditional methods for reducing the effects of turbulence are presented. A simplified method for turbulence reduction called the Sheared Coherent Interferometric Photography (SCIP) method is presented. Implementation of SCIP is discussed along with experimental results. Limitations in the use of this method are discussed along with recommendations for future improvements.
Date: June 1, 1998
Creator: Crawford, Thomas M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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