Flutter instability of a reconfiguring beam

Reconfiguration refers to static and dynamic aeroelastic deflections of structures to flow that provide benefits, such as reduced aerodynamic drag. Assuming small structural deformations, the linear theory is used predominantly in engineering applications. However, large deformations of the trees and aquatic plants can only be explained through large deformation theory. The aim of this research is to study experimentally and numerically the flutter instability in slender structures which deform with great amplitude. In particular, we extend the reduced order model of Leclercq & de Langre¹ to a RANS coupled with a nonlinear beam model handling large displacements. Since the flutter in such flexible structures arises from the strong interaction of the physics of the fluid and the structure domains, we use a partitioned strongly coupled approach with our in-house structural and fluid solvers. This approach enables us to study flutter and provides insights into the drag reduction mechanisms of flexible structures.

¹Leclercq, T., & de Langre, E. (2018). Reconfiguration of elastic blades in oscillatory flow. J of Fluid Mech.