Investigation of a non-conventional blade geometry for enhancing torque generation at low wind speeds

Small-scale wind energy systems operating in regions with low average wind speeds require blade designs capable of maximizing aerodynamic performance under limited flow conditions. This study investigates the torque generation characteristics of a newly developed horizontal-axis wind turbine featuring a non-conventional blade geometry specifically designed for low-speed operation. Two turbine configurations consisting of six and eight blades were numerically evaluated to determine the influence of blade number on torque production. Three-dimensional computational fluid dynamics (CFD) simulations were performed to analyze the aerodynamic behavior of both designs under identical operating conditions. The computational domain was discretized using an unstructured mesh with a maximum mesh size of 5 mm and an element size of 80 mm to ensure adequate solution accuracy while maintaining computational efficiency. Turbulent flow was modeled using the Reynolds-Averaged Navier–Stokes (RANS) approach with the standard k–ε turbulence model. A uniform inlet wind speed of 5 m/s was applied to represent low-wind operating conditions commonly encountered in urban and rural environments. The simulation results revealed distinct differences in the flow field and aerodynamic loading between the two configurations. The eight-blade turbine generated higher torque than the six-blade design, indicating improved aerodynamic energy capture and enhanced rotational performance at low wind speeds. The increased blade count promoted greater interaction with the incoming airflow, leading to more effective momentum transfer and improved torque generation. These findings demonstrate that the proposed non-conventional blade geometry, particularly in the eight-blade configuration, offers a promising approach for improving the performance of low-speed wind turbines and may contribute to more efficient distributed wind energy harvesting in regions with modest wind resources.