Application of a Diffuser Structure to Vertical-Axis Wind Turbines
AbstractThe effects of using a wind acceleration device (wind lens) with vertical-axis wind turbines in wind tunnel experiments were examined. A wind lens consists of a diffuser and flanges, and this study investigated the optimum parameters of their configuration with regard to the power augmentation of the turbines. The wind lens with a flat-panel-type diffuser demonstrated power augmentation by a factor of 2.0 compared with an open wind turbine. An increase from 5° to 20° in the semi-open angle of the diffuser made it possible to generate a 30% high power output over a wide range of tip speed ratios. On that basis, an optimum semi-open angle was determined. For the flat-panel-type diffuser, a recommended diffuser length is the half of the throat width, and its semi-open angle is 20°.The inlet enhanced power augmentation over a wide range of tip speed ratios. The optimum location for the wind lens in the streamwise direction was aligned with the center of the vertical-axis wind turbines. The diffuser with a curved surface was more effective regarding power augmentation than flat-panel-type diffusers. The wind lens with a curved surface diffuser demonstrated power augmentation by a factor of about 2.1 compared with an open wind turbine. Furthermore, it was demonstrated that a two-bladed wind turbine with symmetric NACA0024-type airfoils was most suitable for the incorporation of a wind lens to generate higher power output. View Full-Text
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Watanabe, K.; Takahashi, S.; Ohya, Y. Application of a Diffuser Structure to Vertical-Axis Wind Turbines. Energies 2016, 9, 406.
Watanabe K, Takahashi S, Ohya Y. Application of a Diffuser Structure to Vertical-Axis Wind Turbines. Energies. 2016; 9(6):406.Chicago/Turabian Style
Watanabe, Koichi; Takahashi, Shuhei; Ohya, Yuji. 2016. "Application of a Diffuser Structure to Vertical-Axis Wind Turbines." Energies 9, no. 6: 406.
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