Flow Physics Analyses of a Generic Unmanned Combat Aerial Vehicle Configuration

Abstract

Within the NATO Research and Technology Organisation Applied Vehicle Technology (AVT)-161 task group, \ntitled “Assessment of Stability and Control Predictions for NATO Air and Sea Vehicles,” a 53 swept and twisted \nlambda wing with rounded leading edges is considered. In a first step, the symmetric flow conditions are analyzed in \nthis paper in order to understand the corresponding flow physics. Experiments by the task group are used to develop \nproper numerical simulation tools for further applications in the design process of unmanned combat aerial vehicles \nas a part of future air-combat systems. The philosophy of the configuration under consideration is explained. The \nvortical flowfield is simulated using the DLR, German Aerospace Center TAU-Code applied with different \nturbulence models on various computational grids. Finally, a best practice is evaluated for medium and large angles \nof attack. A combination of these numerical results and experimental data lead to a proper understanding of the \ncomplex flow structure. Furthermore, this paper addresses the necessity for the predictability and understanding of \ncontrolled and uncontrolled flow separation, together with the interaction of the corresponding vortex systems in \norder to estimate stability and control issues for the entire flight envelope.