Optimization of slot parameters for performance enhancement of slotted Savonius hydrokinetic turbine using Taguchi analysis

Hydrokinetic technology is an innovative approach to generate sustainable energy from river systems by using the kinetic energy of free-flowing water. To utilize such energy hydrokinetic turbines are being employed to harness the kinetic energy from flowing water. In this paper, a CFD study has been carried out to improve the efficiency of the Savonius turbine with the application of proposed slotted blades and validated with the experimental study. Also, this study aims for the optimization of a slotted blade Savonius hydrokinetic turbine (SHT) performance by examining different design parameters and their relationship using the Taguchi method. This study reveals that slot gap (y) has the greatest influence on turbine performance, followed by slot shape factor (epsilon), slot position (f), and tip speed ratio (lambda). lambda ). Moreover, the optimal combination of four parameters for maximising the efficiency of the slotted SHT is y =1.5 mm, epsilon = 0.6, f = 1 % of blade diameter, and lambda = 0.7 based on signal-to-noise (S/N) ratio. At this optimum combination of slotted blade profile, performance of slotted blade SHT increases by 45.19 % compared to conventional SHT. There is a slight difference of 4.16 % between experimental and computational results obtained for optimum Taguchi design.