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arXiv · 1903.07244

A Thorough Look at the (In)Stability of Piston-theoretic Beams

Abstract

We consider a beam model representing the transverse deflections of a one dimensional elastic structure immersed in an axial fluid flow. The model includes a nonlinear elastic restoring force, with damping and non-conservative terms provided through the flow effects. Three different configurations are considered: a clamped panel, a hinged panel, and a flag (a cantilever clamped at the leading edge, free at the trailing edge). After providing the functional framework for the dynamics, recent results on well-posedness and long-time behavior of the associated dynamical system for solutions are presented. Having provided this theoretical context, in-depth numerical stability analyses are provided, focusing both at the onset of flow-induced instability (flutter), and qualitative properties of the post-flutter dynamics across configurations. Modal approximations are utilized, as well as finite difference schemes.

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Jason Howell, Katelynn Huneycutt, Justin T. Webster, Spencer Wilder. 2019-03-18. A Thorough Look at the (In)Stability of Piston-theoretic Beams. https://arxiv.org/abs/1903.07244

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