Abstract
The results of a computational fluid dynamics (CFD) study of a three bladed horizontal axis tidal turbine (HATT) are presented. The impact of various parameters in geometry build and numerical setup is discussed. All results provided incorporate the Reynolds Averaged Navier Stokes (RANS) Shear Stress Transport (SST) turbulence model. Simulations cover a range of tip speed ratios (TSR = 3.5 - 8) with a blade root angle of 25° and a constant inflow velocity of 1.54 m/s. The resulting power and thrust coefficients, Cp and Ct, are compared to experimental results for validation purposes. The results show a good level of agreement with possible implications of differences discussed herein. Results of a wake mesh convergence study are also provided. Power and thrust results are shown to be relatively independent of wake mesh size, while wake physics are highly dependent. Furthermore, near and far field wake propagation is investigated and discussed. It was found that the numerical domain length of five diameters is insignificant for complete wake recovery capture. The impact of blade tips, blade roots, and turbine support structure on wake turbulence are illustrated.