Analysis of Incidence of Angle of Attack on Energy Efficiency of a Two-Dimensional Airfoil NACA 1412

The use of airfoils that describe heave and pitching movements simultaneously to extract energy from oncoming fluid, as a turbine, is one of the promising concepts in renewable energy. In this study, the efficiency to extract the energy from the incoming water flow when using a submerged asymmetric airfoil, NACA 1412, is investigated. This moves through a steady laminar regime, (Re = 1100), with forced Heave and Pitching motion. A mapping of efficiencies is constructed hereon for a range of normalized frequencies f* and Pitching angle Ө0 aiming to have a “smooth” surface of energy efficiency. In an earlier investigation, the highest attainable efficiency range stood between 15% and 20%. Nevertheless, in this study, the focus shifts to examining the impact of the effective angle of attack, denoted as α, particularly concerning its effect on efficiency and power extracted. Furthermore, the concept of the feathering parameter χ is employed as an essential prerequisite for the power-extraction regime. The study delves into the investigation of heave amplitude variation with the pitching axis held constant at 33% of the chord length. The ensuing results stemming from the manipulation of these parameters are thoroughly examined, with the aim of achieving an efficiency surpassing 15%. Employing Ansys Fluent as the simulation tool, a dedicated C programming code was formulated and implemented to facilitate oscillatory motion on the airfoil.