On finite amplitude roll cell disturbances in a fluid layer subjected to heat and mass transfer

Abstract

Abstract The system consists of a thin, transversely infinite horizontal fluid layer initially in mechanical but not thermostatic or speciestatic equilibrium. The top and bottom surfaces of the layer are assumed to be unconstrained, and the stability of the system to buoyancy driven finite amplitude roll cell disturbances is investigated. The system is capable of exhibiting both a subcritical stationary and oscillatory instability. The average vertical transport of heat and mass is computed and it is found that the convective transport associated with a stationary type of instability is much greater then that corresponding to an oscillatory instability.