A Numerical Investigation on Effects of the Gap Between Plates of Savonius Vertical Axis Wind Turbines With Different Shapes on Their Performance

Present study introduces the vertical gap between the blades of a Savonius rotor’s blades as a parameter that can enhance performance of the rotor. To provide comprehensive concept about application of gap between blades, two different models were tested in different working conditions and working regimes. The study completed by using R.S.M. turbulence model through ANSYS Fluent commercial software package. Utilization of the method was validated by comparing results of a conventional model with experimental data from one of the references. Results of the study proved that application of a proper gap between blades can improve rotor’s moment coefficient by 20 percent; however, the amount of enhancement and optimum gap are associated with the shape of the blade. Results also demonstrated that the application of vertical gap in a Savonius rotor doesn’t contribute to any change in the optimum velocity coefficient.