Radial Turbine with Pitch-Controlled Guide Vanes for Wave Energy Conversion

Abstract

The performance of radial flow turbines having low rotational speed and low noise level, which can be used for wave energy conversion using the oscillating water column (OWC) principle, has been studied by a number of researchers. According to previous studies, the efficiency of radial turbine with fixed guide vanes was not so high because there are large differences between the absolute outlet flow angle and setting angle of the downstream guide vane, and the downstream guide vane doesn't work as a diffuser. In order to develop a high performance radial turbine for wave energy conversion, a radial turbine with pitch-controlled guide vanes has been proposed and manufactured in the study. The presented radial turbine has been investigated experimentally by model testing using an oscillating airflow rig. Then, the experimental results have been compared with those of the conventional radial turbine, i.e., the radial turbine with fixed guide vanes. As a result, the running characteristics of the presented radial turbine under steady and sinusoidal airflow conditions have been clarified. Furthermore, it seems that the presented radial turbine is superior to the conventional radial turbine.