Numerical study of a circular cylinder effect on the vertical axis savonius water turbine performance at the side of the advancing blade with horizontal distance variations

In this present study, a circular cylinder installation has been performed to increase the conventional savonius performance that has been simulated numerically. Placing a cylinder at the side of the advancing blade has been performed to increase the positive torque and numerical analysis has been performed without and with a circular cylinder. A numerical study has represented by using a 2D analysis of CFD simulation with moving mesh technique. The k-epsilon used is Realizable kepsilon (RKE) by second-order upwind for the discretization method. The numerical simulation uses ANSYS 17.0 software. The first step, the validation is performed by comparing the experimental result with respect to torque coefficient using air fluid. The second step, The fluid has changed into the water fluid and installed a circular cylinder at Y/D of 0.7 kept constant. The parameter X/D has been varied from 0.0 to 2.0 with an increment of 0.5. The best results of the numerical study have been showed that the maximum power coefficient occurs at X/D = 0.5 and the best performance is in about 0.250, increase about 17.31% at a TSR of 0.9.