URANS flow stream in a small VAWT

Abstract

Wind energy is mainly used to generate electricity and more and more with a renewable energy source character. Power production from wind turbines is affected by several conditions like wind speed, turbine speed, turbine design, turbulence, changes of wind direction, 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, parking, 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 VAWT turbines. The turbine has a rotor with three straight blades of symmetrical aerofoil. The paper presents unsteady simulations that have been performed with this turbine .It points up the influence of two different blades geometries for different rotational speeds, different blade stagger angles and different Reynolds numbers related to a wider range of wind speeds.