Adaptive Airfoil

Abstract

"Adaptive Airfoil" is the title of an EREA project launched in January, 1998 with the participation of CIRA, DLR, FFA (now FOI), INTA and ONERA. The main objective of the project is to demonstrate the feasibility and to quantify the benefits of adaptive wing technology. Of the various ways to achieve wing adaptation, i.e. variable camber, suction/blowing, etc. the addition of surface bumps to the original airfoil geometry is an additional possibility. It has been shown recently that the combination of two bumps located at the position of the sonic line and close to the shock foot respectively leads to remarkable improvements with respect to drag reduction and buffet control. Research work in the field of aerodynamics of supercritical airfoils including dual bump systems has shown that beside of the location of the bumps along the upper wing surface, the fine tuning of shapes, height and their time dependent variations are of importance to successfully achieve the objectives. Numerical as well as experimental investigations have been carried out within the scope of the present project.