Performance Comparison of Three-blade and Four-blade Archimedes Wind Turbines in Low Wind Speed Conditions: A Transient CFD Simulation

The increasing global demand for affordable and clean energy (SDG۷) has intensified research into renewable energy technologies, including wind energy, which presents a promising option for regions characterized by low wind speed conditions, such as Indonesia. The wind energy potential in Indonesia exhibits average wind speeds suitable for small-scale power generation applications, although significant regional variability persists. Archimedes spiral wind turbines (ASWTs), characterized by a helical blade geometry, have been investigated as compact and low-noise wind energy converters capable of operating effectively at low wind speeds while requiring relatively simple maintenance. This study compares the aerodynamic performance of three-blade and four-blade ASWT configurations with pitch angle variations of ۵۰°, ۵۵°, ۶۰°, and ۶۵° under low wind speed conditions using transient computational fluid dynamics (CFD) simulations. The results show that the four-blade configuration with a pitch angle of ۶۰° achieves the highest power coefficient of ۰.۲۶۴۲ at a wind speed of ۳ m/s, corresponding to a rotational speed of ۱۵۳.۷ RPM and a tip speed ratio of ۱.۳۴ under transient operating conditions. This configuration demonstrates higher aerodynamic performance compared to the three-blade turbine across the investigated operating conditions. In addition, medium to high pitch angles are found to provide more favorable aerodynamic characteristics than lower pitch angles under low wind speed operation. These findings indicate that increasing blade number and optimizing pitch angle can enhance the aerodynamic performance of ASWTs under transient operating conditions. The numerical results were further assessed through comparison with experimentally and numerically reported performance ranges for ASWTs available in the literature. These findings provide practical design guidance for the development of small household-scale wind energy systems suitable for low wind speed regions, such as Palembang, Indonesia, supporting cost-effective renewable energy solutions for independent urban and rural electrification.

کلیدواژه ها:

Archimedes wind turbine ، Number of blades ، Pitch angle ، Computational fluid dynamics ، Transient Simulation