The State-of-the-Art Technology of H-Type Darrieus Wind Turbine Rotors

There has been a resurgence of interest in the development of small-scale vertical-axis wind turbines (VAWTs) in the past few decades as is evident from the plethora of published scientific work. This attention may be attributed to the desperate need for cheaper, cleaner, and off-grid mechanisms for generating electric power. In such hasty scenario, VAWTs are being considered as one of the potential solution for small-scale power generation. Among the VAWTs, H-type Darrieus rotors have undergone extensive exploration. In this review work, an attempt has been made to assemble all the major areas of research done in the field of H-type Darrieus rotor development. These areas include the aerodynamic models, computational fluid dynamics (CFD) methods and turbulence models, self-starting and dynamic stalling behavior, blade-vortex interaction and wake studies, and blade designs and optimization studies, besides topics of special interest like blade curvature effects and skewed flows. Overall, the work gives a comprehensive review of the state-of-the-art technology of the H-type Darrieus rotor. Finally, recommendations have been made for each of the areas keeping in view of the technological development.