Morphing wing design of truss-braced-wing aircraft through aerodynamic shape optimization using the adjoint method

It is still a challenge to evaluate the benefits of the morphing wing concept with a truss-braced wing wing–body–tail configuration. To address this problem, first, a fair baseline configuration is obtained with a multipoint optimization over six flight conditions. Then, three types of morphing wing design are investigated and compared based on the baseline shape. The results indicate that the simplified variable-camber continuous trailing-edge flap system has the smallest and limited benefit, with only a 0.70% weighted aerodynamic efficiency improvement, which may not be sufficient to cover the extra burden of the increased complexity and weight. The trailing-edge morphing design has a larger benefit, with an efficiency improvement of 1.73%, while the full-wing morphing design achieved the greatest benefit, with a 5.79% efficiency improvement, demonstrating the attractive aerodynamic potential and benefits of the truss-braced-wing aircraft. Further discussion on the drag-reduction sources and some design features is also presented.