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arXiv · 1306.3267

Oscillatory instability of fully 3D flow in a cubic diagonally lid-driven cavity

Yuri Feldman
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Abstract

A transition to unsteadiness of a flow inside a cubic diagonally lid-driven cavity with no-slip boundaries is numerically investigated by a series of direct numerical simulations (DNS) performed on 100^3 and 200^3 stretched grids. It is found that the observed oscillatory instability is setting in via a subcritical symmetry-breaking Hopf bifurcation. The instability evolves on two vortices in a coupled manner. Critical values of Reynolds number Recr=2320 and non-dimensional angular oscillating frequency omegacr=0.249 for transition from steady to oscillatory flow are accurately estimated. Characteristic patterns of the 3D oscillatory flow are presented.

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Yuri Feldman. 2013-06-13. Oscillatory instability of fully 3D flow in a cubic diagonally lid-driven cavity. https://doi.org/10.1007/s00162-015-0351-z

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