Experimental investigation on the performance of a hybrid hydrokinetic turbine having straight-bladed Darrieus rotor and helical-bladed Savonius rotor

Abstract

Hydrokinetic turbine is used to harness the kinetic energy of water stream and can be employed for rivers and canals applications. A hybrid hydrokinetic turbine works on the basis of hybrid force (lift force and drag force). It can be Different configurations of hybrid hydrokinetic turbine rotor having straight-bladed Darrieus rotor and helical-bladed Savonius rotor have been modelled under the present study. An experimental study has been carried out to determine the torque developed by different configurations of hybrid hydrokinetic rotors and presented in this paper. The study was carried out for different Reynolds numbers of 1.35x105, 2.24x105 and 3.14x105 corresponding to different water velocities. Based on the experimental study, it is found that the hybrid hydrokinetic turbine rotor having a Savonius helical blade angle of 0°, performed better in comparison to other configurations. The maximum average torque is observed as 0.36 for a hybrid water turbine rotor having Savonius helical angle of 0° corresponding to TSR value of 0.61 and Reynolds number of 1.35x105. The results of this study may be useful to develop a prototype for field study.