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

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 and
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.