Driving convection by a temperature gradient or a heat current

Bifurcation properties, stability behavior, dynamics, and the heat transfer of convection structures in a horizontal fluid layer that is driven away from thermal equilibrium by imposing a vertical temperature difference are compared with those resulting from imposing a heat current. In particular oscillatory convection that occurs in binary fluid mixtures in the form of travelling and standing waves is determined numerically for the two different driving mechanisms. Conditions are elucidated under which current driven convection is stable while temperature driven convection is unstable.