Wake Modeling of Tidal Current Turbine Array

This paper presents the results of a Computational Fluid Dynamics (CFD) model of a two rotors operating in close proximity. The main purpose was to obtain a validated CFD model of scaled twin rotor laboratory turbine and to model how the wake of these two rotors will affect the performance of individual and collective turbines in future array. The results of numerical methods such as CFD are dependent upon selection of mesh size, length of domain to capture the wake and turbulence model. In this paper steady state RANS CFD simulations were performed by utilizing a Rotating Frame of Reference (RFR) model and shear stress transport (SST) closure model for single, Twin rotor, different domain length and mesh sizes. The obtained results were compared with experimental data. Single rotor performance closely resembles the experimental data while that of twin rotor showed a deviation. With changing of domain length and mesh size the performance became close to the experiment but the wake was quite different showing the limitations of utilized turbulence model.