Simulating the fluid forces and fluid-elastic instabilities of a clamped–clamped cylinder in turbulent axial flow

Jeroen de Ridder (1) , Olivier Doaré (2, 3) , Joris Degroote (1) , Katrien van Tichelen (4) , Paul Schuurmans (4) , Jan Vierendeels (1)

1 UGENT - Universiteit Gent = Ghent University
2 UME - Unité de Mécanique
3 IMSIA - UMR 9219 - Institut des Sciences de la mécanique et Applications industrielles
4 SCK-CEN - Centre d'Etude de l'Energie Nucléaire

In this article, the fluid forces and the dynamics of a flexible clamped-clamped cylinder in turbulent axial flow are computed numerically. In the presented numerical model, there is no need to tune parameters for each specific case or to obtain coefficients from experiments. The results are compared with the dynamics measured in experiments available in literature. The specific case studied here consists of a silicone cylinder mounted in axial water flow. Computationally it is found that the cylinder loses stability first by buckling. The threshold for buckling is in quantitative agreement with experimental results and weakly-nonlinear theory. At higher flow speed a fluttering motion is predicted, in agreement with experimental results. It is also shown that even a small misalignment between the flow and the structure can have a significant impact on the dynamical behavior. To provide insight in the results of these fluid-structure interaction simulations, forces are computed on rigid inclined and curved cylinders, showing the existence of two different flow regimes. Furthermore it is shown that the inlet turbulence state has a non-negligible effect on these forces and thus on the dynamics of the cylinder.

Mots clés: flow-induced vibrations; fluid-structure interaction; eigenmode; numerical simulation; axial flow

Domaines: Mécanique des fluides [physics.class-ph]; Mécanique des structures [physics.class-ph]

Jeroen de Ridder, Olivier Doaré, Joris Degroote, Katrien van Tichelen, Paul Schuurmans, et al.. Simulating the fluid forces and fluid-elastic instabilities of a clamped–clamped cylinder in turbulent axial flow. Journal of Fluids and Structures, 2015, 55, pp.139-154. ⟨10.1016/j.jfluidstructs.2015.03.001⟩. ⟨hal-01215010⟩