Pattern dynamics in a Benard-Marangoni convection experiment

In this paper we report a Benard-Marangoni convection experiment in a small aspect ratio square cell, at a high Rayleigh number. In the time dependent convection regime, low dimensional chaotic behaviour is identified for a variable measured from the pattern. A dynamical system is proposed to model the behaviour of this variable, and predictions induced by this model on the dynamics of the temperature are experimentally verified. The comparison between the experimental data and the one obtained from the model relies on the topological properties (braid type) of unstable periodic orbits.