Analysis of Vertical-Axis Wind-Turbine Clusters Using Condensed Two-Dimensional Velocity Data Obtained from Three-Dimensional Computational Fluid Dynamics

Vertical-axis wind turbine (VAWT) clusters have been investigated extensively owing to their positive aerodynamic interactions. However, accurate predictions of the flow field and power output of each rotor in VAWT clusters using high-fidelity computational fluid dynamics (CFD) remains computationally expensive. In this study, we propose a fast computation method for the flow field and operating state of each rotor of VAWT clusters using temporally and spatially averaged velocity data compressed from an unsteady velocity field obtained via a 3D-CFD simulation of an isolated single rotor. First, the unsteady 3D flow field in the 3D-CFD simulation is time averaged over several revolutions. Next, the temporally averaged velocity is spatially averaged in the vertical direction to obtain spatially compressed data. Based on a previously developed fast computation framework, the wind-farm flow field is constructed using condensed two-dimensional velocity data obtained from a single turbine. The proposed method is applied to three-rotor configurations, and the rotational speeds of the turbines are compared with wind-tunnel measurements. The results show that the proposed method substantially improves prediction accuracy while maintaining a low computational cost. Additionally, it can be used to efficiently design and optimize turbine layouts in VAWT wind farms.