Constructal design applied to geometrical analysis of a triangular arrangement of H-Darrieus wind turbines

The work performs a numerical study of a triangular arrangement of three H-Darrieus wind turbines. There are two constraints: areas of turbines and occupation areas of turbines, and two degrees of freedom: ratio between transversal pitch (ST) of downstream rotors and diameter (D) of turbine and, ratio between longitudinal pitch (SL) of upstream and downstream rotors and diameter of turbine. The purposes are to maximize the power coefficient (Cm) and evaluate the effect of arrangement design on the performance. Three ST/D and eight SL/D are considered. Results showed that ST/D = 2.0 presents a higher interaction between the fluid dynamic boundary layer of the rotors, which implies in an oscillating variation in C-m with variation of the ratio SL/D. The effect of SL/D over C-m have other behaviour for the other ratios of ST/D analysed, variating the optimal ratio for each case, showing that optimal SL/D is dependent of ST/D.