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Study Of The Various Charactertics Of A Helical Vertical Axis Wind Turbine Compared To A Straight Bladed Darrieus Design, Patrick Quinlan

Theses and Dissertations

As the wind energy market continues to expand, the need for a more diverse range of wind turbine technologies becomes increasingly apparent. Horizontal axis wind turbines (HAWT) have become the standard design for wind turbines over the past few decades and have been the go-to design used in wind farms both on land and off-shore. However, in residential and urban environments other types of turbine designs can help expand the reach of wind energy. Specifically, vertical axis wind turbines (VAWT) have shown potential for new applications of wind turbines in areas that are less suitable for typical HAWTs. The most …

Study Of The Various Charactertics Of A Helical Vertical Axis Wind Turbine Compared To A Straight Bladed Darrieus Design, Patrick Quinlan

Theses and Dissertations

As the wind energy market continues to expand, the need for a more diverse range of wind turbine technologies becomes increasingly apparent. Horizontal axis wind turbines (HAWT) have become the standard design for wind turbines over the past few decades and have been the go-to design used in wind farms both on land and off-shore. However, in residential and urban environments other types of turbine designs can help expand the reach of wind energy. Specifically, vertical axis wind turbines (VAWT) have shown potential for new applications of wind turbines in areas that are less suitable for typical HAWTs. The most …

Investigation Of A Novel Turbulence Model And Using Leading-Edge Slots For Improving The Aerodynamic Performance Of Airfoils And Wind Turbines, Saman Beyhaghi

Theses and Dissertations

Because of the problems associated with increase of greenhouse gases, as well as the limited supplies of fossil fuels, the transition to alternate, clean, renewable sources of energy is inevitable. Renewable sources of energy can be used to decrease our need for fossil fuels, thus reducing impact to humans, other species and their habitats. The wind is one of the cleanest forms of energy, and it can be an excellent candidate for producing electrical energy in a more sustainable manner. Vertical- and Horizontal-Axis Wind Turbines (VAWT and HAWT) are two common devices used for harvesting electrical energy from the wind. …

Application Of Reynolds Stress Model Using Direct Modeling And Actuator Disk Approaches For A Small-Scale Wind Turbine, Randall Scott Jackson

Theses and Dissertations

The Reynolds Stress Model (RSM) has been avoided for turbulence closure in CFD simulations of wind turbines, largely due to the computational expense and the high potential for numerical instability. The advantage of using RSM is having access to shear stresses that are not available from two-equation RANS-based closure models like k-e and k-w. Access to the shear stresses will aide in the understanding of how the blade design will affect the wake, particularly in the near-wake region. In this research, the RSM turbulence model has been successfully applied in simulating a three-bladed small-scale wind turbine through a direct-model approach …

Improved Wind Turbine Control Strategies For Maximizing Power Output And Minimizing Power Flicker, Quan Chen

Theses and Dissertations

For reducing the cost of energy (COE) for wind power, controls techniques are important for enhancing energy yield, reducing structural load and improving power quality. This thesis presents the control strategies studies for wind turbine both from the perspectives of both maximizing power output and reducing power flicker and structural load,

First, a self-optimizing robust control scheme is developed with the objective of maximizing the power output of a variable speed wind turbine with doubly-fed induction generator (DFIG) operated in Region 2. Wind power generation can be divided into two stages: conversion from aerodynamic power to rotor (mechanical) power and …

Wind Turbine Controls For Farm And Offshore Operation, Zhongzhou Yang

Theses and Dissertations

Development of advanced control techniques is a critical measure for reducing the cost of energy for wind power generation, in terms of both enhancing energy capture and reducing fatigue load. There are two remarkable trends for wind energy. First, more and more large wind farms are developed in order to reduce the unit-power cost in installation, operation, maintenance and transmission. Second, offshore wind energy has received significant attention when the scarcity of land resource has appeared to be a major bottleneck for next level of wind penetration, especially for Europe and Asia. This dissertation study investigates on several wind turbine …