Aeroelastic modeling and analysis of the wing/engine system of a large aircraft

Abstract An aeroelastic model of the wing/engine system of a large commercial aircraft is established. Taking into account the engine inertia force and thrust, static aeroelastic deformation of the wing structure and load distributions including shear force, bending moment and torque are studied. Models of the clean wing and the wing/engine system are compared and effects of chordwise and spanwise locations of the wing-mounted engines on the wing's natural vibration and flutter characteristics are analyzed. The research indicates that the bending moment at the root part of the wing is alleviated by the engine, and the combination of the engine inertia force and thrust will change the torque there remarkably, while not affect the bending and torsion deformations of the wing structure much. The results also show that wing-mounted engines will affect the wing's natural frequency of vibration, consequently having great effects on the flutter characteristics of the wing. Besides the classic wing flutter induced by the coupling of bending and torsion modes, a low-damping flutter type appears from the coupling of engine-pitch mode and the bending and torsion modes of the wing. Variations in chordwise and spanwise position of the wing-mounted engines will change the frequency of the engine-pitch mode, and further affect the low-damping flutter characteristics mentioned above, to which much attention should be paid in engineering application.