title: Chaotic dynamics of a convection roll in a highly confined, vertical, differentially heated fluid layer.
abstract: Direct numerical simulation is used to study the air flow between two vertical plates maintained at different temperatures. The periodic dimensions of the plates are small so as to accommodate only one flow structure, which consists of a convection roll with oblique vorticity braids. At lower Rayleigh numbers, the roll and the braids grow and shrink alternatively following a cyclical process. As the Rayleigh number is increased, the flow becomes temporally chaotic through a period-doubling cascade. Windows corresponding to multiperiodic regimes and interior crises are observed. As the Rayleigh number is further increased, the structure intermittently switches between two vertical positions, which is seen to correspond to an "attractor-merging" crisis. The chaotic flow dynamics are characterized and the corresponding physical mechanisms are identified. We show that some of the flow key features, such as the chaotic oscillation and intermittency, can be captured by a low-order model.
authors: CNRS, LIMSI, UPR3251, BP 133, 91403, Orsay Cedex, France and Universite Pierre et Marie Curie, Paris 06, 4 Place Jussieu, 75252 Paris, Cedex 05, France and Arts et Métiers ParisTech, 2 Boulevard du Ronceray, 49035 Angers Cedex 01, France.
authors: Zhenlan
authors: Z
authors: Gao
authors: CNRS, LIMSI, UPR3251, BP 133, 91403, Orsay Cedex, France.
authors: Berengere
authors: B
authors: Podvin
authors: CNRS, LIMSI, UPR3251, BP 133, 91403, Orsay Cedex, France and Universite Pierre et Marie Curie, Paris 06, 4 Place Jussieu, 75252 Paris, Cedex 05, France.
authors: Anne
authors: A
authors: Sergent
authors: CETHIL, INSA de Lyon, 69621 Villeurbanne Cedex, France.
authors: Shihe
authors: S
authors: Xin