スクリュー型タービン性能の体積排除率効果に関する考察

抄録

Various wind power generators such as propeller, Darrius and Savonius types have been used. The present study proposed the new screw-type wind turbine. As compared to other power generators, the present one become simpler and more portable. By these advantages, the new applications of the wind power systems such as disaster areas and outdoor activities will be expected. The power characteristics of the screw-type wind turbine were clarified by using a Computational Fluid Dynamics (CFD) and a wind tunnel experiment. The CFD and experimental results show that the maximum-efficiency wind speed is about two times of the tip velocity. The angular momentum flow rates in a control planes surrounding the screw-type wind turbine were examined by the CFD. The results show that the angular momentum flow rate to the axial direction contributes to mainly the power coefficient in the wind speeds larger than the tip speed. On the other hands, the angular momentum flow rate to the radial direction becomes negative when the ratio of the tip speed to the wind velocity is high. That is, the energy of the flow to the radial direction was inversely supplied by the wind turbine. It was confirmed that the low velocity on the blade suction surface caused the negative angular momentum flow rate.