High fidelity physics of fluids and structures for future unmanned air vehicles

As the use of UAVs brings new concepts of air operations, it also brings new critical science issues that need to be identified, studied and understood. We report on a challenge project whose focus is to apply AFRL computational technologies in support of future UAV requirements. A unique, fully nonlinear fluid-structure interaction simulation is documented for a delta wing of moderate sweep that represents the critical physics of future UCAV systems. State-of-the-art LES techniques were used to study natural transition on airfoils because of its criticality for performance of long endurance UAVs. Finally, a systematic study of vortex structures at low Reynolds number was completed to support the conceptual development of micro-UAVs. The second year of this Challenge grant has brought significant contributions to the study of nonlinear, coupled fluid/structures dynamics for future UAV systems.