Potential and Limitations within Conceptual Aircraft Design for the Optimization of a Flexible Wing with and without Load Alleviation

Abstract

Load alleviation is a technology to increase the fuel efficiency of a commercial aircraft by reducing wing mass. The reduction of aerodynamic loads on the transonic, swept outer wing also enables higher aspect ratio wings for new concepts. Load alleviation has an influence on the optimal wing layout and should therefore be taken into account in the conceptual design. This presentation shows a design process that integrates the relevant disciplines into the overall design through simplified but physically-based models. Surrogate model-based optimizations of the wing shape are carried out, where the target parameter is a combined fuel consumption of relevant study missions. The results show that active load alleviation reduces the wing mass and the direct influence of active load alleviation is span-dependent. For the optimization, the optimum with load alleviation shows a potential of 11.6% fuel burn reduction compared to an initial configuration. Even without load alleviation, significant reductions can be achieved through geometry optimization. The reasons for this and boundary conditions such as roll control with a flexible wing are discussed.