Wind in urban areas is extremely complex due to their location in the lower planetary boundary layer, irregular arrangement of buildings and enhanced surface roughness. Vertical axis wind turbines (VAWTs) are used in extracting energy within this environment. However, there is a huge knowledge gap as far as the effect of turbulence on the aerodynamic performance of VAWTs operating in non-uniform wind regimes are concerned. This study used an experimental method to investigate the effect of free stream turbulence intensity on the aerodynamic performance of a VAWT under non-uniform flow operating conditions in a wind tunnel environment. A small-scale Darrieus type VAWT was developed and tested. A wedge mechanism to generate non-uniform conditions was created and the effect of the generated turbulence intensity on the aerodynamic performance of the turbine investigated.

Keywords : Wind Tunnel; VAWT; Turbulence; Power Coefficient; Torque Coefficient.