OPTIMISING TRANSPORT FLYING WINGS

摘要

The research work reported in this paper aims at optimising the planform of a pure flying wing, I.e. with straight leading and trailing edges, conceived as an airliner of the 300 seat class, respecting the 80m wingspan limit. First, the relevant criteria used for design and sizing are discussed, as well as some suitable design constraints. The paper concentrates later into aspect ratio, tapper ratio and Mach number effects. The figures of merit chosen for optimisation are direct operating cost and maximum take-off weight per passenger, for a specified constant range of 10000 km. The optimum aircraft fulfilling all constraints has an aspect ratio of 6.2, carries 277 passengers in three class seating and is near 40 percent more fuel efficient than conventional wide bodies of similar size. By relaxing a secondary constraint the optimum moves to an airplane with 342 seats, aspect ratio of 5.8 and about 11 percent more efficient than the full constrained case.