Advanced numerical modelling of a Vertical Axis Wind Turbine through CFD

Vertical Axis Wind Turbines (VAWTs) are a type of wind turbine that is characterized by having a vertical axis of rotation. These wind turbines represent a a promising al- ternative to fossil fuels for the production of energy that is sustainable. For this reason, they have been the subject of many research studies in order to define their performance and improve their design. However, their unique configuration presents some aerodynamic challenges that require innovative solutions. In fact, the vertical-axis configuration involves unique aerodynamic field complications such as the generation of swirling wake and the interaction of the blades with it. Vortices can cause large fluctuations in the velocity and in the direction of flow at the turbine blades, negatively affecting the overall performance of the turbine, resulting in increased drag aerodynamics and a reduction in the lift force generated by the blades. Therefore, a universal method of simulation based on scientific evidence must be adopted. In this context, this thesis work focused on studying the choice of parameters needed for the fluid dynamic study of vertical axis wind turbines. In the text, the results of numerical analyses based on the equations of Unsteady Reynolds- averaged Navier-Stokes (URANS) equations conducted in order to choose the parameters to evaluate the performance of low Tip Speed Ratio (TSR) VAWTs. In order to find the suitable combination of parameters, each one of them was analysed independently and the results are dicussed. Finally, the validation of the results was conducted on a 3D model comparing the outcome with an experimental study.