ANALISIS ALIRAN FLUIDA PENGARUH VARIASI DIAMETER SILINDER SIRKULAR DISAMPING ADVANCING BLADE TERHADAP PERFORMA TURBIN AIR SAVONIUS DENGAN KOMBINASI MYRING BLADE.
Savonius vertical axes water turbine is a turbine that can work at low fluid flow speeds but still has a high initial torque. However, the power coefficient possessed by conventional Savonius turbine rotors is the lowest among other turbines. Much research has been done to improve the performance of Savonius turbines, including modification by adding a circular cylinder on the advancing blade side so that the speed of fluid flow towards the advancing blade increases, this makes the positive torque generated by the turbine increase. The method used in this study is numerically computational fluid dynamics (CFD), the test model has a height of 40 mm and a diameter of 40 mm. This model is simulated in an open water channel condition with a cross-sectional size of 1100 mm width and 900 mm height. This simulated current speed is assumed at 0.22 m / s. Modifications were made to the blade using a combination of myring n = 1 and n = 2 and added a circular cylinder next to the advancing blade. Placement of the circular cylinder is simulated at a distance of 20 cm and a distance of 28 cm. Circular cylinder diameter variations are ds / D = 0.2; 0.3; 0.4. The results obtained from this research showed that Savonius water turbine variations with ds / D 0.4 were seen to have the highest increase in performance, the highest increase occurred in TSR 1, which increased by 41,186% of Savonius without a barrier. The increase occurred because there was a fairly dominant attach flow and the pressure on the front side of the advancing blade experienced a substantial increase.