Analysis of Flow Past an Aircraft at High Angle of Attack based on Mode Decomposition

Abstract

Various Reduced-Order Modeling (ROM) techniques have been developed for both flow field analysis and aerodynamic load modeling. Proper Orthogonal Decomposition (POD) and later Dynamic Mode Decomposition (DMD) have been used to extract dominant flow features (modes) and have achieved many successes in flow field analysis. However, most of the studies were conducted for flow past a body with relatively simple geometries, such as cylinder, airfoil, or flat plate. In this study, we conduct DMD and POD analysis on flow over a three-dimensional model of aircraft. The effectiveness of these mode decomposition tools on feature extraction from complex flows are evaluated. Also, various flow field quantities, e.g., Q-criterion, and vorticity magnitude will be used as the variable to conduct DMD and POD analysis, and the modes extracted from these variables are compared and discussed.