Time to flutter of a viscoelastic goland wing
A number of aircraft are manufactured from high-polymer composite materials, for example the Predator drone, micro-aerial vehicles, and larger aircraft contain a significant amount of composite material such as the Boeing 787. The increasing use of polymer composite materials adds a time dimension to existing analyses for flutter of an aircraft lifting surface because polymer composites exhibit a viscoelastic material behaviour, in particular energy dissipation and a memory effect. The derivation of the time to flutter theory uses Lyapunov stability principles to provide a set of conditions for stability of a viscoelastic structure. The conditions contain a time parameter that may be isolated, and represents the time to flutter. A generalization of this theory has a number of ramifications including the existence of a finite time to instability for a viscoelastic structure that is a function of the applied loads and material properties. The theory may be applied in practice using a simplified set of bending-torsion equations and will correctly predict the flutter speed of an elastic Goland wing in subsonic, incompressible flow. The equations also predict the time to flutter at other flight speeds for a viscoelastic Goland wing.
|Conference||56th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference 2015|
Merrett, C. (2015). Time to flutter of a viscoelastic goland wing. Presented at the 56th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference 2015.