J056051 Performance and Internal Flow of an Undershot-Type Cross-Flow Water Turbine with Straight Blades

Abstract

An under-shot type cross-flow water turbine does not require a casing for open channels and hence considerable simplification is attained. However, because this water turbine does not have a casing and has free surface, it is believed that the internal flow considerably changes with the rotational speed. In this study, the performance and internal flow of undershot-type cross-flow water turbine with straight blades at a constant flow rate are investigated by an experiment and numerical analysis, and the following facts are clarified. With increase in rotational speed, relative flow angle at the first-stage inlet area is increasing and it at the second-stage inlet area is decreasing.