Aerodynamic performance enhancement of HAWTs via twist angle optimization: A combined critical review and simulation approach

• Meta-analysis of 157 papers on HAWT aerodynamic optimization • Most HAWTs reach Cp = 0.40–0.55; advanced blades up to Cp = 0.64 • CFD shows optimized twist (20.36° root, 11° tip) boosts power by 12.24% • 5 m rotor at 10 m/s yields 5125 W with optimal twist design • Structural insights: thin airfoil AH 7476 maximizes lift but lowers strength This study begins with a comprehensive comparative review of 157 peer-reviewed papers to contextualize the aerodynamic optimization of horizontal-axis wind turbine (HAWT) blades. The meta-analysis reveals that most small- and medium-scale HAWTs achieve a maximum power coefficient (Cp) of 0.4–0.55, with advanced or ducted configurations occasionally reaching up to 0.64. Reported efficiency improvements vary between 5–40%, although some novel approaches demonstrate gains exceeding 70%. Structural innovations such as the use of lightweight composite materials and ply orientation optimization are found to significantly reduce blade weight and deflection. Furthermore, the integration of multi-objective optimization techniques, particularly those combining Blade Element Momentum (BEM) theory with Computational Fluid Dynamics (CFD), has become a common strategy for enhancing both aerodynamic and structural performance. Building on this literature foundation, the current work investigates the effect of varying twist angles at the root and tip of HAWT blades through CFD simulations. Several blade configurations were analyzed to determine their influence on overall aerodynamic efficiency and power output. The results show that optimizing the twist angle, specifically using a 20.36° root twist and an 11° tip twist, can increase power output by up to 12.24% compared to a uniform twist configuration. For a 5-meter diameter rotor operating under 10 m/s wind conditions, this design yields a maximum power output of 5124.67 W. These findings emphasize that selecting the appropriate twist angles at the root and tip is a critical factor in maximizing HAWT performance, reinforcing its role in broader aerodynamic and structural optimization strategies.