The effect of along blade surface discretization on the Savonius hydrokinetic turbine performance by using Myring formula for n = 1

Abstract

The hydrokinetic turbine is one of the renewable energy without generating emission impacted on environmental. In this work, the numerical simulation is used to investigate the influence of discretization along the blade surface towards the amount of the torque coefficient and power coefficient. This work will be done on Savonius hydrokinetic turbine numerically by using the Myring formula for n equal with 1 having the performance better than the conventional blade. This work will compare the performance among the blade discretization. Firstly, the numerical will be validated with experimental results at TSR of 0.8 and velocity of fluid kept constant at 0.22 m/s. Problem-solving uses Unsteady RANS with moving mesh for the rotating body. The turbulence model uses the Realizable k-epsilon (RKE) enhanced wall treatment with the discretization varied 200, 400, 800 and 1,600. The first layer number is 20 layers on the blade surface. This work obtains the torque coefficient and power coefficient. The results indicate that the increase of discretization on the surface of the blade has improved the accuracy results of the turbine performance by seeing the stability of graphic at 800 and 1,600. This Savonius model of Myring formula can use the number of the layer around 800 towards time efficiency.