Investigation of performance gains on a sailplane with morphing wing trailing edge

Abstract

Increasing the performance of a modern sailplane is challenging. Most of the known valid approaches have already been applied in practice. Morphing technology, which could allow to adapt to various flight stages is yet to be applied. An investigation of possible flight performance benefits of such technology is carried out here. Using a genetic algorithm, a morphing trailing edge flap for airfoil HQ-17 is formed for -4° and +12° flap deflections. The performance is evaluated and compared with a regular flap, which shows that for the HQ-17 airfoil, drag could be reduced by up to 36% in comparison with regular flap. To show the advantage of morphing flaps, a hypothetical sailplane wing is modeled and evaluated with morphing and conventional flaps using non-linear LLT method. Results show that incorporation of a morphing flap could extend the flight envelope and increase the L/D ratio by 2-5% trough the full flight speed range.