Optimization of segmented flaps for in-flight transonic performance enhancement

A 'smart trailing edge' design concept consisting of a segmented flap trailing edge system is studied to determine the potential payoffs for reducing drag at off-design flight conditions. The flap system being developed will employ smooth hinge lines and a new type of electromagnetically driven smart material linear actuator completely embedded in the wing structure. A smart trailing edge system consisting of three independently actuated flap segments is studied. Numerical optimization is carried out to determine the optimum location of the hinge lines and optimum deflections for minimum drag using a full potential solver coupled to an integral boundary layer method. The results of the optimization are checked for validity and flow separation using a Navier-Stokes solver. For all flight conditions, the flap system was shown to reduce drag, indicating promise for the concept. (Author)