Study on a Cross-Flow Water Turbine Installed in an Open Channel

Abstract

This study is aimed at development of the extra-low head water turbine for an open channel from a viewpoint of using effectively unused hydropower energies, such as an irrigation channel. Then, paying attention to the cross-flow runner, authors eliminated the casing and tried the application as a water turbine for an open channel. In this paper, water turbine performance, the flow situation characteristics, and the flow in the runner were experimentally investigated about the water turbine. As a result, the following facts became clear. When initial depth of water is shallow, turbine efficiency is high in a low rotation region, and when initial depth of water is deep, turbine efficiency is high in a high rotation region. Unlike the runner in which the cross-flow runner which does not have a bottom plate has a bottom plate, air bubbles do not stagnate between blades to blade. Moreover, winding up of the water by a blade does not arise. Therefore, in a wide range rotation region, an output and turbine efficiency improves substantially.