A comparative analysis of rotating airfoils focusing on aerodynamic performance and airflow patterns through 2D unsteady simulations

The blade section of a wind turbine plays a pivotal role in harnessing the power of the wind to generate clean and renewable energy. Each turbine blade is carefully designed with specific aerodynamic principles in mind, primarily focusing on lift and drag forces. Understanding the intricacies of aerodynamics in this context is crucial for optimizing energy capture and ensuring the overall efficiency of wind power systems. In this context the present paper investigates the aerodynamics of three airfoils named NACA-4412, NACA-23012, and NACA-63415 using numerical simulations performed with Ansys Fluent software, with a specific focus on performance and airflow patterns. Through two-dimensional unsteady simulations, the computational approach thoroughly explores the impact of rotational speeds (ranging from 2 to 16 degrees per second) and a range of Reynolds numbers from 1.25e6 to 2e6. The findings illustrate the dynamic interplay between airflow patterns and operational factors. Variations in velocity magnitude, influenced by rotational speeds and Reynolds numbers, were observed. These variations provided additional insights into flow behavior near the airfoil, including the identification of flow separation regions, as depicted by the velocity vectors. Analysis of lift coefficient values revealed a minimal variation concerning changes in rotational speed, suggesting 8 degrees per second as an appropriate rotational speed for the studied cases. Examination of airfoil aerodynamic coefficient trends highlighted noteworthy findings. Drag coefficient values exhibited an increasing variation over time, with higher values observed in the case of the NACA-63415 airfoil. On the other hand, lift coefficient values displayed an increasing variation reaching a maximum value, followed by a decreasing trend. Notably, the NACA 4412 airfoil demonstrated superior aerodynamic coefficients compared to the other studied airfoils.