Bio-Inspired Hybrid Dragonfly–Owl Wind Turbine Blade for Enhanced Energy Harvesting under Low Wind Speed Conditions

Efficient utilization of low-speed wind resources remains a significant challenge for small- and medium-scale wind turbines because of low starting torque, premature flow separation, and aerodynamic losses. This study presents the design and aerodynamic evaluation of a bio-inspired dragonfly–owl wind turbine blade developed to improve energy extraction under low wind speed conditions. The blade combines dragonfly-inspired corrugated surface geometry with owl-inspired leading-edge serrations and trailing-edge fringes, integrating complementary passive flow-control mechanisms within a single blade configuration. A three-dimensional blade model was developed using computer-aided design (CAD) software and investigated using computational fluid dynamics (CFD) under steady-state operating conditions representative of low-speed wind environments. The aerodynamic characteristics of the hybrid blade were compared with those of a conventional blade based on velocity distribution, pressure contours, turbulence intensity, lift coefficient, drag coefficient, lift-to-drag ratio, and power coefficient. The numerical analysis indicated improved airflow attachment and modified vortex development over the biomimetic blade surface, together with improved pressure distribution and reduced wake disturbances. The combined corrugation and serration features enhanced the aerodynamic behavior of the blade by promoting more stable flow structures and delaying flow separation. These effects contributed to improved lift generation and aerodynamic efficiency, thereby indicating enhanced starting and low-speed operating characteristics compared with the conventional configuration. The owl-inspired serrated leading edge also demonstrated potential for mitigating unsteady wake structures and aerodynamic noise. The results indicate that combining dragonfly and owl morphological characteristics can provide an effective flow-control strategy for low-speed wind energy applications. The biomimetic blade offers a promising approach for developing compact, efficient, and environmentally compatible wind turbines for distributed renewable energy generation.