Numerical Investigation of Installed Rod Effects in Front of an ASymmetric Blade section of Vertical Axis Wind Trubine

The Darrieus wind turbine is a lift-based vertical axis wind turbine which has been considered because of simplicity in design and its independency from wind direction. In this study, the effect of a rod mounted on the blade leading edge on the aerodynamic performance of the turbine has been investigated, and various parameters such as torque coefficient and power coefficient have been studied. Ansys Fluent software is used to simulate the turbine. Furthermore, two-dimensional computational fluid dynamics method and k-ω SST turbulence model are used. According to the results, the prespce of the rod causes a delay in flow separation and increases the output torque and power of the turbine. This phoenemon in symmetrical blades can increase the torque at high tip speed ratios between 2.5 to 3.5, which results in an increase in the power coefficient. Also using this rod, the generating power increases by 23% at the tip speed ratio of 3.2, and the optimum tip speed ratio is shifted from 2.7 to 3.2, which results in an increase in turbine efficiency. Applying rod on asymmetric blades as opposed to symmetric blades not only improves the low power efficiency but also solves the problem of turbine self-starting Darrieus turbine.