Effect Of Domain Size on 2d and 3d CFD Modeling of a Vertical Axis Wind Turbine

Abstract: Due to the rising pollution in the atmosphere and depleting fossil fuel supplies renewable sources of energy have started to gain popularity in the past few years. The vertical axis wind turbine (VAWT) has some distinct advantages over the conventional horizontal axis wind turbine (HAWT) which include no requirement of yaw control, ease of maintenance, etc., as a result the inclination of the industry towards vertical axis wind turbine (VAWT) is increased in the recent past. The performance of VAWT and its efficiency are investigated in this article using computational fluid dynamics simulation in ANSYS Fluent software. The current study simulates 2D and 3D threebladed VAWT by using unsteady Reynolds-averaged Navier-Stokes (URANS) model. The current study systematically examines the effect of different domain sizes on the VAWT performance (i.e., minimize the effect of blockage and unreliability of the boundary condition) by keeping the blade profile, rotor diameter, chord length and setting angle fixed for the three-bladed VAWT operating at a modest tip speed ratio. The results obtained are validated with the available literature and later the domain size is varied for understanding its effect. It is concluded that the domain size has a significant impact on the numerical results and it is highly essential to opt efficient domain size for obtaining the correct behavior of wind flow pattern.