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arXiv · 1012.2369

Vortex shedding patterns, their competition, and chaos in flow past inline oscillating rectangular cylinders

Srikanth Toppaladoddi·Harish N Dixit·Rao Tatavarti·Rama Govindarajan
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Abstract

The flow past inline oscillating rectangular cylinders is studied numerically at a Reynolds number representative of two-dimensional flow. A symmetric mode, known as S-II, consisting of a pair of oppositely-signed vortices on each side, observed recently in experiments, is obtained computationally. A new symmetric mode, named here as S-III, is also found. At low oscillation amplitudes, the vortex shedding pattern transitions from antisymmetric to symmetric smoothly via a regime of intermediate phase. At higher amplitudes, this intermediate regime is chaotic. The finding of chaos extends and complements the recent work of Perdikaris et al. [1]. Moreover it shows that the chaos results from a competition between antisymmetric and symmetric shedding modes. Rectangular cylinders rather than square are seen to facilitate these observations. A global, and very reliable, measure is used to establish the existence of chaos.

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Srikanth Toppaladoddi, Harish N Dixit, Rao Tatavarti, Rama Govindarajan. 2010-12-10. Vortex shedding patterns, their competition, and chaos in flow past inline oscillating rectangular cylinders. https://arxiv.org/abs/1012.2369

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