Flow Instability Modelling in Air foils Using the k Epsilon Turbulence Model Algorithm

Abstract

It is paramount to understand and predict flow instability over the surface of the air foils to improve performance and stability in aerospace engineering. This study is focused on the investigation of flow instabilities using the k-ε turbulence model; a two-equation turbulence closure approach and one of the most widely used turbulence models. Computational fluid dynamics (CFD) tools were utilized to simulate a boundary layer's separation, transition, and reattachment of an air foil and under a variety of both Reynolds numbers and angles of attack. The features of the k-ε model being robustly solved turbulent kinetic energy and its dissipation rate provide insight into areas of flow instability in both the wake and near wall regions. Validation will be performed against laboratory experimental data to understand the accuracy of the model. The results provide confidence in the robustness of the k-ε in capturing the key instability zones and allow for better optimization in design for air foil applications in both the subsonic and transonic flight regimes.