Computer Simulation Studies on the Effect Overlap Ratio for Savonius Type Vertical Axis Marine Current Turbine

The Ocean has provided a new avenue in the quest for renewable energy. One potentialsource of energy is marine current, which is harnessed using either vertical or horizontal axis turbines.This paper describes a particular type of vertical axis turbine which is suitable for low current velocityapplications. The simulation of Savonius-type turbine, which hitherto has never been proposed formarine current energy application, is presented in this paper. A 3D computational model was builtand analyzed using a Computational Fluid Dynamic analysis using proprietary software. The overlapratio is identified as one of the important factors in Savonius turbine performance. This paperprovides results of the investigation for a range of overlap ratios between 0.1 and 0.6 and it was foundthat the maximum torque can be obtained at overlap ratio of 0.21.