Numerical study of two-bucket Savonius wind turbine cluster

The performance of a single Savonius turbine depends on the interaction between the buckets of its rotor. Recent studies also show that interactions between Savonius turbines in a cluster enhance the output power of individual rotors. The purpose of this study is the development of a multi-turbine cluster for construction of efficient patterned vertical axis wind turbine farms. Numerical solutions are performed for a single Savonius turbine, clusters of two turbines in parallel and oblique positions, and triangular clusters of three turbines facing the wind forward and backward. The commercial CFD software FLUENT 14.5 is used for the numerical simulation. The numerical results of the single Savonius turbine are validated against experimental data. Parametric studies are performed to determine the solution domain size, the grid density, and the turbulence model. The two parallel and oblique turbine clusters are simulated to determine the optimum gap distances and setting angles between adjacent turbines for the maximum power coefficient. The numerical results of the two turbine oblique clusters are used to develop an efficient triangular shaped three turbine cluster. The developed three turbine cluster has an average power coefficient up to 34% higher than that of an isolated turbine.