The Effect of Laminar Compared to Turbulent Airfoils on the Aeroelastic Assessment of a Long-Range Transport Aircraft Configuration

Abstract

The within the ongoing DLR project LamTA (laminar tailored aircraft) presently developed long-range wide-body transport aircraft is used as reference configuration for this investigation. The planform of the LamTA wing is designed to achieve a long laminar running length together with rear-loaded airfoils to reduce its aerodynamic drag. To investigate the effect of the different airfoil shapes on the structural and aeroelastic characteristics of the aircraft compared to a classical turbulent wing, a second configuration is set up. For the second, so-called 'turbulent' configuration, the main wing airfoils are exchanged with transonic airfoils of the well-known Common-Research-Model (CRM), while the planform and the relative profile thickness distribution along the span is kept the same. In addition, the jig-twist of the turbulent wing is adapted, so that both wings meet the desired flight-twist-distribution. The influence of the different airfoil shapes on the elastic loads and the resulting optimized wing-box mass are shown. Furthermore, the effect of the eventuated change in the spanwise stiffness distribution on the dynamic aeroelastic stability are investigated.