Research on the Aerodynamic Characteristics of Morphing Supercritical Airfoil

Abstract

Morphing vehicle would change aerodynamic configuration in real time with the flight condition changing to keep the best performance in the whole flight envelope, which would result in strong flow unsteadiness and the response problem between flow and the airframe. Aiming at these problem, multiple methods were applied to study how the flow would change during the morphing. Unsteadiness brought by the supercritical airfoil thickness and camber continuous deformation was studied with computational fluid dynamics (CFD). The results show that deformation of airfoil thickness and camber would change the pressure distribution obviously. And the unsteady effect is strong with distinguishable lift and drag hysteresis loops. As the morphing frequency and amplitude increase, the unsteadiness would be strengthened. The unsteady effect resulted from the camber deformation is relatively stronger than that from the thickness deformation. The research show that the unsteadiness come from the hysteresis between the flow structure (location/strength of shock and the boundary separation during) and the airfoil morphing.