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Global attenuation of structural velocities is one of the most effective approaches in order to reduce noise emitted by shell structures such as a car roof or aircraft fuselage panels. This global reduction can be achieved by the application of passive damping treatments like constraint layer damping on large fractions of the vibrating surface. The main disadvantage of this approach arises from the fact that it leads to increasing total cost and weight of the structure. To overcome this problem, acoustic black holes can be used to create locations with high vibration amplitudes and low bending waves velocity in order to dissipate the energy of structure borne sound by very limited application of damping treatments. Acoustic black holes are funnel shaped thickness reductions that attract sound radiating bending waves and allow a global vibration reduction by an acceptable use of additional damping.

The following paper describes a multidisciplinary approach to design a wing with almost optimal aerodynamic efficiency during the entire cruise flight. Therefore a tight collaboration between structural mechanics and aerodynamics is necessary. Aerodynamic aspects are described here to illustrate the interdisciplinary nature of the design process, but they are not explained very deeply. The paper focuses on structural aspects, e.g. description of the tasks of the wings structural members, their placement within the wing and the modeling of the actual wing structure.