Study on Aerodynamic Performance Characteristics for SMART BLADE according to Turbulence Model

Abstract

This study presents an analysis of the aerodynamic performance characteristics of 20 m rotor blades for the NREL CART3 wind turbine within the SMART BLADES and SMART BLADES-2 projects. Three-dimensional Computational Fluid Dynamics (CFD) analysis was conducted to investigate the aerodynamic behavior. The Reynolds Averaged Navier-Stokes (RANS)-based turbulence model was utilized for numerical simulations, and the results were compared with Fraunhofer’s Blade Elementary Momentum Theory (BEMT) results. The aerodynamic performance characteristics of the rotor blades were evaluated using three turbulence models: Spalart Allmaras (S-A), standard k-ω, and Shear Stress Transform (SST) k-ω. The turbulence models demonstrated good agreement with the BEMT results at wind speeds below the rated power. However, under rated power wind speed conditions, the S-A and standard k-ω turbulence models exhibited an underprediction of aerodynamic performance. This discrepancy was attributed to an overestimation of the flow delamination point and recirculation region near the blade hub. Therefore, it is recommended to employ the SST k-ω turbulence model, which accurately captures turbulence phenomena both inside and outside the boundary layer, for rated power speed conditions.