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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.
21

Numerical simulation of local climatic impact of an operating wind turbine

Yang, Yuan, 杨源 January 2012 (has links)
Wind energy is commonly considered to be a clean and environmentally friendly renewable energy resource, as they do not pollute our atmosphere with greenhouse gas, nor do they cause any radioactive problems compared to nuclear energy. However, there are still some environmental impacts due to the installation and operation of the wind turbines that cannot be ignored, such as noise, visual and climatic impact. Especially, the observed local climate change in some wind farm areas has attracted general concern in recent years. Experts suspected that long time operation of wind turbines in an area can cause changes to local precipitation, evaporation of the water on earth surface, and even affect the frequency of drought happening. Nevertheless, we still cannot figure out whether these changes would be caused by wind turbines or not. The target of this study is to investigate the potential local impact of an operating wind turbine by numerical simulation. Because of the big geometric size of commercial wind turbines, experimental method is very limited in this type of study. Numerical simulation using CFD is considered to be a suitable approach and commercial software “FLUENT” is utilized in this study. Firstly, an accurate 3-D numerical wind turbine model was established and the frozen blade method was used to realize the rotation of the wind blades. Before further simulation, a wind-tunnel test has been undertaken by using a scaled physical wind turbine model for validation purpose. The experimental results show good agreement with those predicted by the numerical simulation. This suggested that the computation results were validated and the computational model can be used for further study. In this research, three wind turbine cases, with different typical ambient temperature and surface temperature, were simulated. Characters like wake structure, turbulence intensity and local temperature change was collected and analyzed in each simulated case. The results show that the operating wind turbine can bring obvious velocity deficit in the wake and a strong turbulence intensity enhancement was observed at the top tip because of the rotation. Also, local temperature change was found in the near wake region. The investigation of the local impact of the operating wind turbine is very significant. This study provides a valuable insight into the potential impacts of wind farms on local meteorology, which is rarely studied before. Meanwhile, a more comprehensive study on the effect of a wind farm on the environment is highly recommended. / published_or_final_version / Mechanical Engineering / Master / Master of Philosophy
22

A simulation-based procedure for reliability anaylsis of wind turbines

Saranyasoontorn, Korn 28 August 2008 (has links)
Not available / text
23

Dynamic analysis of high-speed wind-turbine systems.

Duggal, Jatinder Singh. January 1970 (has links)
No description available.
24

Sail aerofoil applied to a vertical-axis wind turbine

Robert, Jean. January 1977 (has links)
No description available.
25

Aerodynamics of Darrieus wing turbine and energy measurements downstream of wind turbine arrays of limited size

Goldenberg, Joachim. January 1980 (has links)
No description available.
26

Performance analysis and life prediction for small wind turbine blades : a wood laminate case study : a thesis /

Nosti, Christopher James, Lemieux, Patrick. January 1900 (has links)
Thesis (M.S.)--California Polytechnic State University, 2009. / Title from PDF title page; viewed on November 5, 2009. Major professor: Patrick Lemieux, Ph.D. "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Mechanical Engineering ." "August 2009." Includes bibliographical references (p. 176-178). Also available on microfiche.
27

Fully coupled dynamic analysis of a floating wind turbine system /

Withee, Jon E. January 1900 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology, 2004. / Available from National Technical Information Service, Springfield, Va., 2004. Includes bibliographical references (150-151).
28

Composite material bend-twist coupling for wind turbine blade applications

Walsh, Justin M. January 2009 (has links)
Thesis (M.S.)--University of Wyoming, 2009. / Title from PDF title page (viewed on June 15, 2010). Includes bibliographical references (p. 103).
29

Wind tunnel blockage corrections : an application to vertical-axis wind turbines /

Ross, Ian J. January 2010 (has links)
Thesis (M.S. in Aerospace Engineering) -- University of Dayton. / Title from PDF t.p. (viewed 06/22/10). Advisor: Aaron Altman. Includes bibliographical references (p. 101-104). Available online via the OhioLINK ETD Center.
30

The aerodynamic control of the V-type vertical axis wind turbine.

Robotham, Antony John. January 1989 (has links)
Thesis (PhD)-Open University. BLDSC no.DX92970.

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