Abstract : Rayleigh-Bénard convection is studied in a rectangular geometry with a spatial forcing induced in one direction by electric wires. When using fluids of relatively large Prandtl numbers, this forcing allows the existence of a perfect one-dimensional pattern until the onset of bimodal convection. The transition to bidimensional convection is studied for increasing Rayleigh number and reveals the existence of different spatio-temporal regimes depending on the value of the forcing. At the onset of the transition, a stationary pattern is observed for weak forcing, while travelling waves are evidenced for strong forcing. Both behaviours give place to collective oscillations at higher Rayleigh number.
François Daviaud, A Burnol, O Ronsin. Travelling and Standing Waves in a Spatially Forced 2D Convection Experiment . Europhysics Letterss, 1991, 16 (7), pp.667-672. ⟨cea-01374013⟩