Aerodynamic performance optimisation of an airfoil using with Synthetic Jets Actuation

Abstract

This Bsc thesis presents an analysis of the aerodynamics of the Eppler149 airfoil profile.The Eppler149 is a symmetrical airfoil specifically designed for low Reynolds numbers, making it suitable for small aircraft, drones, and unmanned vehicles. The aim of this thesis is to perform an aerodynamic analysis of the Eppler149 airfoil, at flight conditions of Reynolds 60000, at an angle of attack of 16 degrees, which is considered as post-stall, and it could be particularly relevant for takeoff operations. To conduct the analysis, a structured C-type domain has been designed, using an hybrid mesh structured and unstructured created on gmsh software, and subsequently imported into OpenFOAM, for simulations. Three turbulence models, k-e, k-wSST, and Spalart-Allmaras models, have been examined to determine the most accurate and suitable model for our case. Through a comprehensive evaluation, the Spalart-Allmaras turbulence model has demonstrated the best performance and was selected for further analysis. To improve the aerodynamic behavior of the airfoil, a suction jet has been designed on the extrados surface of the airfoil, at intensities of 0%, 50%, 100% and 150% referenced to Reynolds in flight conditions. This active flow control technique aimed to enhance the performance and efficiency of the airfoil. Furthermore, a comparative study has been conducted by varying the shape of the leading edge to analyze its impact on aerodynamic performance. The findings of this research provide valuable insights into the aerodynamic characteristics of the Eppler149 airfoil at low Reynolds numbers and high angles of attack. The results highlight the effectiveness of the Spalart-Allmaras turbulence model in accurately predicting the flow behavior around the airfoil. The implementation of active flow control through suction demonstrated improvements in the aerodynamic performance of the airfoil, while the investigation of leading-edge variations shed light on their influence on aerodynamic performance.