Computation of Patterns in Convecting Flows

Rayleigh-Benard convection represents a "simple" flow whose complexity is easily regulated. A Rayleigh-Benard cell consists of a fluid layer confined between two horizontal conductive plates. A temperature gradient can be imposed across the layer by heating the bottom plate and cooling the upper plate. 

When the temperature gradient reaches some critical value, buoyancy forces dominate the dissipative effects of viscosity and thermal conduction. The fluid becomes unstable to the occurrence of convecting rolls that mix the warm fluid near the bottom plate with the cool fluid neat the top plate.