Effect of the System Geometry on the Flow Stability of an Evaporating Liquid

In this paper, we study the exact stationary solution of the Oberbeck–Boussinesq equations describing the joint flow of a viscous heat-conducting liquid and the cocurrent flow of a gas-vapor mixture in a flat horizontal layer. The initial formulation of the problem takes into account mass transfer through the interphase interface due to evaporation, vapor diffusion in the gas phase in the presence of diffusion heat conduction, and a longitudinal temperature gradient at the solid impermeable boundaries of the channel. The effect of the layer thickness of working media on the characteristics of the main flow under conditions of equal thermal load on the channel walls was studied. Based on the linear theory, the stability of the exact solution is studied, typical forms of perturbations and their dynamics are determined with a change in the linear dimensions of a system, and neutral curves and maps of the instability regimes are plotted.