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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.
51

Study on the Electromagnetic Type of the Wave Power Conversion System

Tsai, Chih-Hsuan 30 August 2011 (has links)
The wave power converstion system nowadays nearly all have to depend on the converstion of mechanical energy.This way frequently causes unnecessary loss to the power.The costs of maintenance will also be high about the way. Therefore,we bring up a new wave power converstion system according to Faraday's Law.This way is no need to have the turbine.It can be catch the induced current from the generator directly. We use three different types of the PVC tubes as the model of the magnetic field and put into the round magnet.The motion of the round magnet will cause the change of the magnetic field to product the induced current.We install the magnet with the tube on a platform and combine them to be a structure.Different tubes, structure period and structure displasement will cause different effect of the generator.We apply to the data of experiments to find the relationship of the generator, structure period and structure displacement.We also use the neural network to build the model of the relationship. Finally, it will be the basis on the design of the real model in the future.
52

On the use of computational models for wave climate assessment in support of the wave energy industry

Hiles, Clayton E. 02 November 2011 (has links)
Effective, economic extraction of ocean wave energy requires an intimate under- standing of the ocean wave environment. Unfortunately, wave data is typically un- available in the near-shore (<150m depth) areas where most wave energy conversion devices will be deployed. This thesis identities, and where necessary develops, ap- propriate methods and procedures for using near-shore wave modelling software to provide critical wave climate data to the wave energy industry. The geographic focus is on the West Coast of Vancouver Island, an area internationally renowned for its wave energy development potential. The near-shore computational wave modelling packages SWAN and REF/DIF were employed to estimate wave conditions near-shore. These models calculate wave conditions based on the off-shore wave boundary conditions, local bathymetry and optionally, other physical input parameters. Wave boundary condition were sourced from theWaveWatchIII off-shore computational wave model operated by the National Oceanographic and Atmospheric Administration. SWAN has difficulty simulating diffraction (which can be important close to shore), but is formulated such that it is applicable over a wide range of spatial scales. REF/DIF contains a more exact handling of diffraction but is limited by computational expense to areas less than a few hundred square kilometres. For this reason SWAN and REF/DIF may be used in a complementary fashion, where SWAN is used at an intermediary between the global-scale off-shore models and the detailed, small scale computations of REF/DIF. When operating SWAN at this medium scale a number of other environmental factors become important. Using SWAN to model most of Vancouver Island's West Coast (out to the edge of the continental shelf), the sensitivity of wave estimates to various modelling param- eters was explored. Computations were made on an unstructured grid which allowed the grid resolution to vary throughout the domain. A study of grid resolution showed that a resolution close to that of the source bathymetry was the most appropriate. Further studies found that wave estimates were very sensitive to the local wind condi- tions and wave boundary conditions, but not very sensitive to currents or water level variations. Non-stationary computations were shown to be as accurate and more computationally efficient than stationary computations. Based on these findings it is recommended this SWAN model use an unstructured grid, operate in non-stationary mode and include wind forcing. The results from this model may be used directly to select promising wave energy development sites, or as boundary conditions to a more detailed model. A case study of the wave climate of Hesquiaht Sound, British Columbia, Canada (a small sub-region of the medium scale SWAN model) was performed using a high resolution REF/DIF model. REF/DIF was used for this study because presence of a Hesquiaht Peninsula which has several headlands around which diffraction was thought to be important. This study estimates the most probable conditions at a number of near-shore sites on a monthly basis. It was found that throughout the year the off-shore wave power ranges from 7 to 46kW/m. The near-shore typically has 69% of the off-shore power and ranges from 5 to 39kW/m. At the near-shore site located closest to Hot Springs Cove there is on average 13.1kW/m of wave power, a significant amount likely sufficient for wave power development. The methods implemented in this thesis may be used by groups or individuals to assess the wave climate in near-shore regions of the West Coast of Vancouver Island or other regions of the world where wave energy extraction may be promising. It is only with detailed knowledge of the wave climate that we can expect commercial extraction of wave energy to commence. / Graduate
53

Novel design and implementation of a permanent magnet linear tubular generator for ocean wave energy conversion /

Prudell, Joseph H. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 105-106). Also available on the World Wide Web.
54

Towards reliable and survivable ocean wave energy converters /

Brown, Adam C. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 45-48). Also available on the World Wide Web.
55

Investigation and comparison of generators for dynamic operation in ocean buoys /

Schacher, Anthony Clinton. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2005. / Printout. Includes bibliographical references (leaf 89). Also available online.
56

Towards reliable and survivable ocean wave energy converters

Brown, Adam C. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Title from PDF title page (viewed Aug. 22, 2009). Includes bibliographical references (leaves 45-48).
57

Estimating oceanic internal wave energy from seismic reflector slope spectra

Helfrich, L. Cody. January 2008 (has links)
Thesis (M.S.)--University of Wyoming, 2008. / Title from PDF title page (viewed on June 24, 2009). Includes bibliographical references.
58

A linear test bed for characterizing the performance of ocean wave energy converters /

Hogan, Peter M. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 125-126). Also available on the World Wide Web.
59

Harvesting energy from the sea

Leclercq, Mathilde January 2012 (has links)
Every marine energy source presents advantages and disadvantages. For example, they are not atthe same stage of maturity. Tidal range power is fully mature but the limited number of sitesavailable, combined with the large environmental impacts and investment costs limit itsdevelopment. The idea of artificial lagoons that will be offshore tidal range plant could create a newinterest for this technology. But for the moment, no plant of this type has been constructed yet. Tidalstream power is the next mature technology of marine energy after tidal range. Its development willrequire public subsidies but is supposed to be commercial in 2015. Systems are already indemonstration in several countries (UK, France and Canada). Wave power is less mature but it willbenefit from the development of tidal stream power and will probably be commercial in 2020. Somesystems are also in demonstration but challenges seem greater in wave power than in tidal power.Wave power conversion systems have to extract energy from the waves, even the largest ones, butat the same time resist to them. Contrary to tidal stream which has a predictable resource, waves areway less predictable and systems will have to be able to resist and valorize waves. OTEC (OceanThermal Energy Conversion) has been studied for years but it is still not mature. Its development forelectricity production needs technology research to develop cheaper and more compact systems(heat exchangers, pipes…). Air conditioning applications are developing and also require the use ofpipes and heat exchangers. Advances in this utilization could maybe help the development of OTECsystems for electricity production. Osmosis is the less mature and the most challenging technology. Atechnological breakthrough in the membrane could allow a rapid development. This breakthroughwill probably come from other sectors so it is important for the industries to get ready in order todevelop the system as soon as this technological improvement will be made.
60

Optimal design of Hagen-Cockerall raft

Haren, Pierre January 1979 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 120-121. / by Pierre Haren. / M.S.

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