• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.8
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• pp.693-702
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• 2015

This paper presents the performance characteristics of a Darrieus-type vertical-axis wind turbine (VAWT) with National Advisory Committee for Aeronautics (NACA) airfoil blades. To estimate the optimum shape of the Darrieus-type wind turbine in accordance with various design parameters, we examine the aerodynamic characteristics and separated flow occurring in the vicinity of the blade, the interaction between the flow and blade, and the torque and power characteristics that are derived from it. We consider several parameters (chord length, rotor diameter, pitch angle, and helical angle) to determine the optimum shape design and characteristics of the interaction with the ambient flow. From our results, rotors with high solidity have a high power coefficient in the low tip-speed ratio (TSR) range. On the contrary, in the low TSR range, rotors with low solidity have a high power coefficient. When the pitch angle at which the airfoil is directed inward equals $-2^{\circ}$ and the helical angle equals $0^{\circ}$, the Darrieus-type VAWT generates maximum power.

• The KSFM Journal of Fluid Machinery
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• v.14 no.3
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• pp.45-49
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• 2011

This paper describes the numerical analysis of effect of geometric variation on the straight-bladed vertical axis wind turbine. Geometry variation is performed with pockets on the blades. The results presented in this numerical analysis show the general flow pattern of near the bladed, and azimuth angle variation on stating torque value. It is shown that the pockets makes torque higher about 80%.