CFD Analysis without Turbulence Models of Aerodynamic Characteristics for Horizontal Axis Wind Turbine

In the design for a wind turbine, the validation of the numerical computation result is almost carried out by the comparisonwith the wind tunnel experiment. However, the Reynolds number of the wind tunnel experiment is low and the flowdoes not become turbulence fully developed on a leading edge of wind turbine blade. Therefore, the transition area fromlaminar to turbulence becomes wide under the conditions, and the separation point is difficult to predict using the turbulencemodels. The prediction precision extremely decreases in the tip speed ratios less than a maximum power point. This studycarries out the unsteady calculation without and with turbulence models for a 3-blades horizontal axis wind turbine. Thevalidation of the calculations is performed by comparing with the experimental results. The power coefficients calculatedwithout turbulence models are in agreement with the experimental data for the high tip speed ratio heiger than 5.