VAWT with controlled blades : influence of wake of one turbine on power coefficient on the next turbine

Abstract

Power production from wind turbines is affected by several conditions like wind speed, turbine speed, turbine design, turbulence, changes of wind direct ion, wake of previous turbines. These conditions are not always optimal and have negative effects on most turbines. The present wind turbine is a small one which allows to be used on roofs or in gardens to light small areas like publicity boards, parkings, roads or for water pumping, heating... This turbine is less affected by these conditions because the blades combine a rotating movement around each own axis and around the main turbine’ s one. Due to this combination of movements, flow around this turbine is more optimized than classical Darrieus turbines. It has been shown in previous studies that the best configuration was obtained with straight blades, a blade stager angle comprised between 0 and 8 degrees and a range of non-dimensional velocity from 0.4 to 0.6 for a very good power coefficient of about 0.4 in case of one VAWT. The present study points up the influence of the position of each VAWT in a group of three turbines and of the distances between turbines. It deals on global and local performances of these turbines.