Performance assessment of savonius hydrokinetic turbine in a sharp 90° channel bend

Abstract

Hydrokinetic technology is a new and competitive source of renewable energy in remote areas. Previous research on the impacts of the presence of this type of turbine have often been conducted in straight channels, and the effect of the presence of a turbine in a channel bend has not been studied yet. This study aims to investigate for the first time the effects of the siting of the Savonius hydrokinetic turbine in an open channel bend on the turbine performance. In addition, two rotation modes of the turbine, including clockwise and counter-clockwise have been investigated. Results showed that the siting of the turbine inside the bend increases the maximum power coefficient from 5 % to 30 % compared to the condition in which the turbine is located in the upstream straight channel. The maximum power coefficient occurred when the turbine was sited in section 90° for fully submerged conditions. In this section, the maximum power coefficient reaches 0.417 and 0.398 for the counter-clockwise and clockwise rotation modes, respectively. It was also observed that the values of the power coefficient in all sections for the counter-clockwise rotation mode of the turbine are higher than those for the clockwise rotation mode of the rotor.