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arXiv · 0910.1747

Bifurcations and chaos in large Prandtl-number Rayleigh-Bénard Convection

Supriyo Paul·Pankaj Wahi·Mahendra K. Verma
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Abstract

A low-dimensional model of large Prandtl-number ($P$) Rayleigh Bénard convection is constructed using some of the important modes of pseudospectral direct numerical simulations. A detailed bifurcation analysis of the low-dimensional model for $P=6.8$ and aspect ratio of $2\sqrt{2}$ reveals a rich instability and chaos picture: steady rolls, time-periodicity, quasiperiodicity, phase locking, chaos, and crisis. Bifurcation analysis also reveals multiple co-existing attractors, and a window with time-periodicity after chaos. The results of the low-dimensional model matches quite closely with some of the past simulations and experimental results where they observe chaos in RBC through quasiperiodicity and phase locking.

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Supriyo Paul, Pankaj Wahi, Mahendra K. Verma. 2009-10-09. Bifurcations and chaos in large Prandtl-number Rayleigh-Bénard Convection. https://arxiv.org/abs/0910.1747

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