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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
451

Thermodynamic considerations in devising on external combustion gas turbine engine refuse incinerator

Craig, Gale M. 03 June 2011 (has links)
Study and experiment indicate that, with existing technology, a modified open Brayton cycle can be used to burn common municipal refuse at atmospheric pressure and produce useful power while scrubbing the combustion product gases to remove pollutants.The hot combustion gases pass from a combustor through a turbine to a region below atmospheric pressure where they are scrubbed and cooled by mixing with water spray. The water spray and gas mixture is then exhausted to atmospheric pressure through a compressor.Although current compressor designs are workable in this application, a new design is needed which will have reduced water drag power loss.Ball State UniversityMuncie, IN 47306
452

Raptor Mortality and Behavior at Wind Turbines Along the North Shore of Lake Erie During Autumn Migration 2006-2007

Dance , Kevin January 2011 (has links)
During 2006 and 2007 behavioral observations surveys of raptors were conducted at 12 turbines of a 66-turbine wind farm near Port Burwell, Ontario, Canada. Mortality surveys were conducted at all turbines in the wind farm with additional search effort at the twelve turbines where behavioral monitoring was conducted. The wind farm is located along a significant autumn raptor migration corridor along Lake Erie which is in the area of the Central Flyway. Only one raptor fatality was found each year at the 12 turbines used in the study, with one additional fatality found at the other 54 turbines in the wind facility. The estimated mortality rate for Erie Shore Wind Farm ranged from 0.028 to 0.049 raptor fatalities/MW/autumn. The estimated mortality rate for Erie Shores is at the low end of mortality for North American wind facilities outside of California, and which are not located in known migratory pathways. My findings suggest that the presence of high numbers of migrant raptors passing over a wind facility site does not automatically equate to high collision mortality. Over 5,579 observations of individual raptor passes within 250m of a turbine were recorded. The majority of raptors (73%) passed outside of blade sweep height. The majority of raptors avoided entering the risk zone of operational turbines with 2.92% (n = 159) of raptors observed passing within the risk zone of blade sweep height above ground and 0-40m out from the turbine base. The majority (73%) of raptors that entered the risk zone did so under conditions when risk was reduced due to turbine blade orientation in relation to the raptors’ direction of movement or when the turbine was not operational.
453

The Application of MEMS Microphone Arrays to Aeroacoustic Measurements

Bale, Adam Edward January 2011 (has links)
Aeroacoustic emissions were identified as a primary concern in the public acceptance of wind turbines. A review of literature involving sound localization was undertaken and led to the design of two microphone arrays to identify acoustic sources. A small-scale array composed of 27 sensors was produced with the intention of improving the quality of sound measurements over those made by a single microphone in a small, closed-loop wind tunnel. A large-scale array containing 30 microphones was also implemented to allow for measurements of aeroacoustic emissions from airfoils and rotating wind turbines. To minimize cost and pursue alternative sensor technologies, microelectromechanical microphones were selected for the array sensors and assembled into the arrays on printed circuit boards. Characterization of the microphones was completed using a combination of calibration techniques, primarily in a plane wave tube. Array response to known sources was quantified by analyzing source maps with respect to source location accuracy, beamwidth, and root mean square error. Multiple sources and rotating sources were tested to assess array performance. Following validation with known sources, wind tunnel testing of a 600 watt wind turbine was performed at freestream speeds of 2.5 m/s, 3.5 m/s, 4.5 m/s, and to 5.5 m/s. Significant aeroacoustic emissions were noted from the turbine in the 4.5 m/s and 5.5 m/s cases, with an increase of up to 12 dB over background levels. Source maps from the 5.5 m/s tests revealed that the primary location of aeroacoustic emissions was near the outer radii of the rotor, but not at the tip, and generally moved radially outward with increasing frequency. The azimuthal location of the greatest sound pressure levels was typically found to be between 120º and 130º measured counterclockwise from the upward vertical, coinciding with the predicted location of greatest emissions provided by an analytical model based on dipole directivity and convective amplification. Analysis of the acoustic spectra, turbine operating characteristics, and previous literature suggested that the sound emissions emanated from the trailing edge of the blades.
454

Modeling creep behavior in a directionally solidified nickel base superalloy

Ibanez, Alejandro R. 01 December 2003 (has links)
No description available.
455

Design of Magnetic Flux for a High Speed Generator

Lai, Dong-Yi 13 February 2008 (has links)
none
456

Interactions entre rangées d'aubes et effets de Clocking dans un étage et demi de turbine

Billiard, Nicolas Trebinjac, Isabelle. January 2006 (has links) (PDF)
Thèse de doctorat : sciences. Turbomachines : Ecully, Ecole centrale de Lyon : 2006. Thèse de doctorat : sciences. Turbomachines : Rhode-Saint-Genèse (Belgique), Institut von Karman de dynamique des fluides : 2006. / 158 réf.
457

Interactions entre rangées d'aubes et effets de Clocking dans un étage et demi de turbine

Billiard, Nicolas Trebinjac, Isabelle. January 2006 (has links) (PDF)
Thèse de doctorat : sciences. Turbomachines : Ecully, Ecole centrale de Lyon : 2006. Thèse de doctorat : sciences. Turbomachines : Rhode-Saint-Genèse (Belgique), Institut von Karman de dynamique des fluides : 2006. / 158 réf.
458

Simulation aux grandes échelles de la combustion étagée dans les turbines à gaz et son interaction stabilité-polluants-thermique

Schmitt, Patrick Poinsot, Thierry January 2005 (has links)
Reproduction de : Thèse de doctorat : Dynamique des fluides : Toulouse, INPT : 2005. / Texte en anglais. Titre provenant de l'écran-titre. Bibliogr. 108 réf. Index.
459

Simulations aux grandes échelles

Prière, Céline. Poinsot, Thierry January 2005 (has links)
Reproduction de : Thèse de doctorat : Dynamique des fluides : Toulouse, INPT : 2005. / Titre provenant de l'écran-titre. Bibliogr. 91 réf.
460

Contribution à l'amélioration du couplage thermodynamique entre l'installation de la turbine à gaz et l'installation de la turbine à vapeur dans les centrales électriques à cycles combinés gaz/vapeur

Cenusa, Victor-Eduard Feidt, Michel Benelmir, Riad. Badea, Adrian. January 2004 (has links) (PDF)
Thèse doctorat : Mécanique et Energétique : Nancy 1 : 2004. Thèse doctorat : Mécanique et Energétique : Universitatea politehnica (Bucarest) : 2004. / Thèse soutenue en co-tutelle. Titre provenant de l'écran-titre.

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