Date of Graduation
1979
Document Type
Dissertation/Thesis
Abstract
A method has been developed to analyze the flow and predict the lifting characteristics of vertical axis wind turbines. Blades are modelled by a number of discrete bound vortices located on the airfoil mean camber line; the wake is modelled by a number of discrete vortices shed from the blade trailing edge. Application of the flow tangency boundary condition and the Kutta condition permit a numerical solution for the strengths of the bound vortices. Blade forces are then determined from potential theory. This vortex model faithfully reflects the important phenomena of flow unsteadiness and wake/blade interaction. Wake details and energy extraction efficiency are analyzed for single and multi-bladed turbines. A comparison of experimental data to analytical predictions shows elose agreement for the maximum power coefficient and the tip speed ratio at which it occurs. A numerical procedure for estimating the theoretical maximum attainable power coefficient suggests that vertical axis turbines may exceed the Betz limit for horizontal axis machines.
Recommended Citation
Migliore, Paul Gerald, "A Free-Vortex Model With Numerical Solution For The Unsteady Lifting Characteristics Of Straight Bladed Darrieus Wind Turbines." (1979). Graduate Theses, Dissertations, and Problem Reports. 9419.
https://researchrepository.wvu.edu/etd/9419