Investigations on the Potentials of Novel Technologies for Aircraft Fuel Burn Reduction through Aerostructural Optimisation

Abstract

A physics-based optimisation framework is developed to investigate the potential advantages of novel technologies on the energy efficiency of a midrange passenger aircraft. In particular, the coupled-adjoint aerostructural analysis and optimisation tool FEMWET is modified to study the effects of active flow control at different load cases for conventional and unconventional wing configurations. This multidisciplinary design optimisation (MDO) framework presents the opportunity to optimise the wing considering static aeroelastic effect and, by its gradient-based method, save substantial computational time compared to high-fidelity tools, keeping a satisfying level of accuracy. Two different configurations are analysed: a forward- and backward-swept wing aircraft, developed inside the Cluster of Excellence SE2A (Sustainable and Energy-Efficient Aviation). The forward-swept configuration is sensitive to the aeroelastic stability effect, and the backward configuration is influenced by the aileron constraint. They may lead to a weight increment. Sensitivity studies show the possible role of key parameters on the optimisation results. The highest fuel weight reduction achievable for the two configurations is 5.6% for the forward-swept wing and 9.8% for the backward configuration. Finally, both optimised wings show higher flexibility.

Design of Hybrid-Laminar-Flow-Control Wing and Suction System for Transonic Midrange Aircraft

“…The overall aircraft optimization using DLR F-15 airfoil and assuming a laminar flow length of 60 % on the wing estimates a fuel weight reduction of 9.8 % for the backward swept mid-range aircraft [49]. Compared to this value and accounting for the actual suction power and the system weight, it can be expected that the maximum fuel weight reduction possible for the mid-range aircraft corresponds to 6.9 % for Case I and 8.6 % for Case II.…”