流入ノズル付きダリウス形水車の性能に及ぼす側壁隙間とランナ翼枚数の影響

概要

論文の詳細を見る
A ducted Darrieus-type turbine has been proposed for extra-low head hydropower utilization of total head less than 2m. It was clarified in previous paper that in the case of installing a three-bladed runner in the duct with an inlet nozzle, the narrow clearance between the runner pitch circle and side-walls was not necessary for keeping the performance high, which yields no draft tube. Considering that four- or five- bladed runner might be adopted in practical use. the effects of side-wall clearance on the performance of runner with various blade number have to be clarified for higher performance design. In the present paper, turbine performance of three-, four- and five bladed runners are experimentally examined for two kinds of side-wall clearance. Then, it is shown that there is little influence of the casing clearance on the efficiency in the case of installing the inlet nozzle and without deteriorating turbine efficiency the structure of turbine can be simplified by removing the side-wall at the runner section and the draft tube even in the case of four- and five-bladed runner.
ターボ機械協会の論文
2009-04-10