Optimization of an angle between the deflector plates and its orientation to enhance the energy efficiency of Savonius hydrokinetic turbine for dual rotor configuration.

Many efforts have been made to enhance the hydrokinetic turbines' energy efficiency, extracting the energy from the flowing water in the canal and river. Savonius hydrokinetic turbine is one of the turbines producing mechanical power output using renewable energy sources of flowing water. It has good starting characteristics but has low energy efficiency. In the present investigation, an attempt is made toward the enhancement of the energy efficiency and load-carrying capacity of the Savonius turbine. The two dual-rotor Savonius turbine designs with deflector plates are proposed termed as Dual Rotor with Diverging Deflector Plate (DR-DDP) and Dual Rotor with Converging Deflector Plate (DR-CDP). The investigations are carried out with numerical simulations. The experiments are also performed for the validation of the methodology adopted in the presented numerical simulations. The results indicate the improved performance of the turbine units with both deflector plate designs. The power coefficient with the Savonius turbine unit's investigated design is enhanced from 0.135 of the conventional turbine to 0.16 with DR-DDP, and that up to 0.20 with DR-CDP. [ABSTRACT FROM AUTHOR]