往復流型二重反転衝動タービン

(可変ピッチ案内羽根による性能改善)

抄録

In a wave energy plant with oscillating water column (OWC), an air turbine is adopted as an energy conversion device. The counter-rotating impulse turbine for wave energy conversion has been proposed by M. E. McCormick in 1978. In a previous study, authors investigated the effect of turbine geometry on the performance, and clarified that the efficiency of this turbine is higher than single rotor impulse turbine in the range of high flow coefficients. In this study, the pitch-controlled guide vanes were installed in order to achieve a further improvement in the performance of a counter-rotating impulse turbine, and the effect of guide vanes on turbine characteristics was investigated by using the computation fluid dynamic (CFD) analyses. As a result, it was found that the effect of the setting angle of the guide vanes has significant influence on the turbine performance, and inlet and outlet setting angle of θi=22.5° and θo=45°, respectively, obtained the better efficiency.