Studies on Cavitation Occurring on the Runner Blade of a Darrieus-Type Water Turbine

抄録

Cavitation tests were carried out on a Darrieus-type cross-flow water turbine, which could be put into practical use for small water power. In the present paper, cavitation phenomena occurring on the Darrieus runner with various blade sections are explained and the characteristics of the incident cavitation coefficient for the attack angles in relative flow around the Darrieus blades are also evaluated with theoretical considerations of the difference between the circular motion of the Darrieus blades and the linear motion of those in a uniform steady flow. As the result, a useful method is proposed for estimating the required net positive suction head (NPSH) of a Darrieus-type water turbine.