Control of Laminar Boundary-Layer Separation on a Rectangular Wing using Decambering Approach

This paper investigates an improvement of the aerodynamic performance of a rectangular wing by re-designing its camberline to control the laminar separation of its boundary layer. This is experimentally implemented using an Aluminium secondary skin on the wing surface, which aligns itself to the separated boundary layer, such that the flow remains attached to it, which otherwise would have separated on the baseline configuration. The shape of the skin, which is now regarded as the effective flow surface, is essentially a decambered version of the baseline shape of the wing and is predicted numerically using an in-house code based on two linear functions that account for the local deviation of camber by accounting for the difference in coefficients of lift and pitching moments. Aerodynamic characteristics of the effective decambered configurations using numerical analysis, CFD, and wind tunnel experiments are reported. Results indicate that significant improvement in aerodynamic performance can be achieved for laminar separation control through this active flow surface.