On thermocapillary instability of a liquid column with a co-axial gas flow

The thermocapillary flows and their stability in an infinite liquid column surrounded by a co-axial gas layer with a given flow rate are investigated. The gas layer is surrounded by a rigid cylindrical surface, which can move in vertical direction. A constant axial temperature gradient is maintained in the layers. The exact solution describing the stationary flow in the given two-phase system is derived. Possible flow regimes are investigated and linear stability analysis of these regimes is performed. The cases of non-deformable and deformable interface are studied.