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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.
111

Development of wind resource assessment methods and application to the Waterloo region

Lam, Vivian January 2013 (has links)
A wind resource assessment of two sites in the Waterloo region, WRESTRC and RIM Park, was conducted using wind speed, wind direction, temperature and pressure data collected from meteorological towers for over two years. The study was undertaken as part of the W3 Wind Energy Project, and the equipment was purchased from NRG Systems and R. M. Young Company. The data was filtered to reduce the effect of icing and tower shadow, and was analyzed using MATLAB software. Based on the mean wind speeds, small wind turbines less than 50 kW in capacity would be appropriate at both sites. Wind speeds tended to be stronger during the winter than the summer, and during the afternoon than the rest of the day. Both sites also exhibited a strong dominant wind direction -- from the northwest. Due to the terrain, the wind shear and turbulence intensity at WRESTRC were moderate when the wind flowed from the dominant direction, but very high from other directions. The wind shear and turbulence intensity at RIM Park were consistently moderate in all directions. Although the terrain seems more complex at WRESTRC, the wind speed distribution and estimated annual energy production were higher at WRESTRC than at RIM Park, which indicates that it is a more viable site. The estimated capacity factors ranged from 9.4% to 22% depending on the hub height, which is not nearly high enough to suggest a commercial wind farm would be viable at either site. A small 5 kW to 15 kW wind turbine in the Waterloo region could offset the electricity usage of an average home. A two-parameter power law model of wind shear was explored and compared with the standard one-parameter model. In terms of goodness-of-fit, the two-parameter model did perform better. But in terms of accuracy of extrapolation, it was not conclusively better or worse than a one-parameter model forced through the known data point closest to the prediction height. The relationship between turbulence intensity and measurement interval was examined. Since atmospheric flow is unsteady, they are not independent. The perceived turbulence intensity was found to increase exponentially with time intervals under 24 hours. Two linear regression-based Measure-Correlate-Predict methods were evaluated using long-term data from a weather station also at WRESTRC. The ordinary least squares method was considered the baseline given its simplicity. The variance ratio method improved upon it by ensuring that the variance of the wind speed distribution at the target site was preserved.
112

Dialectics for wind ensemble

Harman, Brian. January 2006 (has links)
Dialectics is a musical composition for 32-instrument wind ensemble. The materials and models used in the piece are based entirely on the harmonic series and on naturally-occurring acoustical phenomena that are stretched out in time, and that undergo a variety of transformational processes. A dialectic is created between two musical principles, each based in a different manner on the concept of reverberation.
113

Using Mesoscale Meteorological Models to Assess Wind Energy Potential

Green, Michael Paul January 2005 (has links)
As the demand for safe and clean electricity increases, the New Zealand wind energy industry seems poised to expand. Many generating companies have projects in the planning stage and there are likely to be many more potential sites yet to be identified. Reliable wind climate predictions over a wide area and for different heights above grounds are often vital to determine the viability of wind farm projects. This study investigates the use of meteorological mesoscale models to determine the wind and energy resource, particularly in areas of complex terrain. Complex terrain environments are likely to be typical of where New Zealand wind energy developments will take place. Using the prognostic mesoscale meteorological model TAPM (The Air Pollution Model), regions of relatively high mean wind speed were identified for a number of regions, including Banks Peninsula and parts of Canterbury and Otago. The simulations were conducted for a one-year period (2001) and at different heights above ground level. Depending on the resolution of the model calculations, speed-up effects from the forcing of some topographic features were accounted for by this model. Where the modelling was considered reliable, hourly wind data were obtained from grid points within the inner grid and used as input data for the industry-standard wind energy assessment model WAsP (The Wind Atlas Analysis and Application Program). As WAsP is able to account for detailed topography and surface roughness features, wind and energy predictions at a specific site or over a wider area surrounding the site were made. Limitations of both models in complex terrain were identified. These limitations were due to a number of factors, including the grid spacing used for mesoscale model calculations, the complexity of the terrain, and difficulties in modelling some regional scale airflow regimes. Being aware of when and where model limitations are likely to occur is important in being able to overcome and account for them.
114

A wind tunnel study of the velocity field above a model plant canopy

Styles, Julie M. January 1997 (has links) (PDF)
Thesis (B.Sc. (Honours)) - Australian National University, 1997. / Title from title screen (viewed on May 20, 2002). "A thesis submitted in partial fulfilment of the requirements for the Degree of Bachelor of Science (Honours)"--Title screen. Bibliography: p. 64-66. Available full text via the internet.
115

Interference effects on wind loading of a group of tall buildings in close proximity

Zhao, Jianguang. January 2008 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (p. 219-225). Also available in print.
116

Predictive engineering in wind energy a data-mining approach /

Li, Wenyan. Kusiak, Andrew. January 2009 (has links)
Thesis supervisor: Andrew Kusiak. Includes bibliographic references (p. 141-147).
117

Assessment of methods used to investigate the impact of offshore wind farms on seabirds

Brookes, Kate Louise. January 2009 (has links)
Thesis (Ph.D.)--Aberdeen University, 2009. / Title from web page (viewed on Feb. 18, 2010). Includes bibliographical references.
118

Stratifications of upper level winds using height difference and geostrophic vorticity

Snyder, Earl Paul. January 1961 (has links)
Thesis (M.S.)--University of Wisconsin, 1961. / Also published as AFCRL-TN-61-844, and University of Wisconsin Dept. of Meteorology Scientific report no. 5. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 43).
119

Temporal and spatial wind field distribution in Delaware Bay

Haag, Christian. January 2006 (has links)
Thesis (M.E.E.)--University of Delaware, 2006. / Principal faculty advisors: Kenneth E. Barner, Dept. of Electrical and Computer Engineering; and Mohsen Badiey, Dept. of Marine and Earth Studies. Includes bibliographical references.
120

Doubly fed induction generator (DFIG)-based wind power generation system simulation using real-time digital simulator (RTDS) a thesis presented to the faculty of the Graduate School, Tennessee Technological University /

Wang, Ge, January 2009 (has links)
Thesis (M.S.)--Tennessee Technological University, 2009. / Title from title page screen (viewed on June 29, 2010). Bibliography: leaves 147-152.

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