A solution-based stall delay model for horizontal-axis wind turbines

This paper presents a solution-based stall delay model to predict rotational effects on horizontal-axis wind turbines. In contrast to conventional stall delay models that correct sectional airfoil data prior to the solution to account for three-dimensional and rotational effects, a novel approach is proposed that corrects sectional airfoil data during the solution process by investigating the spanwise circulation distribution along the blade and other solution-dependent parameters. The wind turbine performance analysis code XTurb-PSU iterates over modified sectional lift and drag data until a converged circulation distribution is obtained. Results obtained show good agreement with measured data along the NREL Phase VI and MEXICO rotor blades at low and high wind speeds.