Aerodynamic and Aeroelastic Behavior of Wings in the Presence of Upstream Vortical and Viscous Disturbances
Abstract
We propose an integrated experimental and theoretical research study aimed at improvedunderstanding of the flow physics and fluid-structure interactions of an unsteady airfoil encounteringdifferent types of wakes from upstream disturbances. For the airfoil encountering the wakes, we consider both prescribed motion and flow-induced oscillation due to elasticity of the airfoil support. The degrees of freedom for the airfoil motion will include arbitrary pitch, plunge and flap motions. The wake effects on an airfoil undergoing prescribed motion will be studied in a water tunnel, which provides highly reliable aerodynamic force measurements even for high-intensity motions. The aeroelastic experiments will be carried out in a wind tunnel, which results in realistic fluid-body inertia ratios for aeronautical applications. By using canonical upstream flow disturbances, we plan to separate out the effects of flow-angle perturbations and flow-velocity perturbations to better understand the flow physics of wake effects. A strong emphasis of the research is to use the experimental studies to guide low-order modeling of wake effects and subsequently provide model validation. The aim is to augment an exisiting unsteady airfoil theory that is capable of handling leading-edge vortex shedding, trailing-edge separation, and aeroelastic effects due to elastic supports. Wake effects will be modeled by altering the no-flow-through boundary conditions. Through systematic experimental and theoretical studies, the proposed research effort will provide valuable insight into wake effects along with a low-order modeling approach, thus contributing to practical applications such as close formation flight, store separation, and wake-induced flutter.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 28, 2017
- Source ID
- FA95501710301
Entities
People
- Ashok Gopalarathnam
Organizations
- Air Force Office of Scientific Research
- North Carolina State University
- United States Air Force