Melting glass furnace mathematical modelling currently includes coupled simulations of electrical boosting, bubbling, flame radiation, etc... Increasing modelling complexity may also result from consideration of unsteady solutions. Different sources of thermoconvective unsteadiness can be considered: pull modification, time variation of bubbling and/or boosting, shift of the temperature profile or, finally, colour change, this paper will present the numerical solutions to the last unsteady coupled mixing problem.
