We present an experimental study of stationary convection in a binary mixture at positive values of a separation ratio. The interplay between the Rayleigh-Bénard and the Sorét mechanisms of instability and the corresponding boundary conditions gives us the possibility to observe a transition from large- to small-scale structures as well as a transition between patterns with different symmetries. We also investigate an influence of lateral boundaries and the cell geometry on the pattern selection.

• Received 27 April 1990

DOI:https://doi.org/10.1103/PhysRevA.43.707