STATIC AEROELASTIC TAILORING OF A HIGH-ASPECT-RATIO-WING FOR A SAILPLANE WITH A FORWARD MORPHING WING SECTION

A sailplane with a morphing forward wing section allows a promising increase in performance. As a consequence, the morphing forward section leads to a smaller primary structure and reduced torsional stiffness. As the shear center is moved aft the aerodynamic center, an aeroelastic twisting moment is induced on the high-aspect-ratio wing. The layup and fiber angles of the wing shells are optimized to counteract the adverse wing twist by modifying stiffness and applying bending-torsion-coupling. An efficient parametrization and optimization method of the wing skin layup is developed for a finite element shell model of the wing structure. The aerodynamic model utilizes a doublet lattice model, based on an optimized aerodynamic wing design for a morphing wing sailplane. Structural masses and masses for controls, flaps and water ballast are included with discrete mass elements. To solve the static aeroelastic problem and to determine the deflection, NASTRAN SOL144 is used. Load cases for low- and high speed conditions as well as for pull-up manoeuvres are analyzed. Results show that the bending-torsion-coupling effect can have a beneficial or adverse effect depending on the specific load case and aerodynamic configuration.