Resonance and phase solitons in spatially-forced thermal convection (Q1090542)

The competition between external and internal length scales is studied theoretically, on a two-dimensional amplitude evolution model of a fluid layer heated from below. A spatially-periodic excitation is applied to the stress-free, isothermal boundaries at a wavenumber close to the critical wavenumber for the onset of the instability. Near resonance, the large-scale phase dynamics give rise to stationary phase solitons at high Prandtl numbers and propagating sine-Gordon solitons at low Prandtl numbers. The propagating solitons are associated with the external breaking of the Galilean invariance of the problem.