A novel airfoil selection and blade optimization strategy for sustainable small wind turbines under low-Reynolds-number flow
The aerodynamic efficiency of small wind turbines (SWTs) depends strongly on airfoil selection, yet the balance between aerodynamic, structural, and sustainability factors under low-Reynolds-number conditions remains insufficiently explored. This study proposes a sustainability-driven, multi-criteria framework integrating aerodynamic performance, structural reliability, and material efficiency. Thirty airfoils from NACA, Selig, Eppler, and NREL families were analyzed over Re = 100,000–500,000 using an in-house MATLAB viscous panel-based solver coupling potential-flow formulation with viscous boundary-layer and transition corrections. Four criteria—glide ratio, maximum lift coefficient, stall stability, and Material Efficiency Index (MEI)—guided the selection of BW-3, E-216, and SG6041 for genetic-algorithm blade optimization. BEM and aeroelastic simulations, supported by preliminary ULS and FLS checks, identified SG6041 as the best compromise between aerodynamic performance, startup behavior, structural safety, fatigue resistance, and material mass. The framework supports lightweight, sustainable SWT blades using date-palm-fiber composites.