Effect of turbulence on a Savonius type micro wind turbine

The primary objective of this paper is to investigate the effect of turbulence of a multi-bladed micro vertical axis wind turbine with semi-circular shaped blades in a wind tunnel environment under a range of wind speeds. A 24, 32 and 40-bladed rotor with corresponding distance between 2 subsequent blades of 35 mm, 17.5 mm and 9 mm was initially designed and its power outputs were measured. The turbulence was generated inside the wind tunnel using 3 different passive grids with same blockage area at the inlet. The turbulence intensity was measured at different positions in the wind tunnel from the grid. It was observed that the turbulence intensity increases with the increase of grid size with the same blockage ratio. The result also shows that the power output of a multi-bladed Savonius rotor decreases with the increase of turbulence intensity. (C) 2017 The Authors. Published by Elsevier Ltd.