Flow regimes of a liquid film carried away by a gas flow in a flat horizontal channel under isothermal conditions

A three-dimensional mathematical model of the flow of a liquid film carried away by a gas flow in a flat horizontal minichannel under isothermal conditions has been developed. A numerical simulation of the film flow regimes in the evaporative cooling system has been carried out. Dependences of the development of the deformation on the control parameters of motion, such as the Reynolds numbers for liquid and gas, are studied. The hydrodynamic flow regimes found in the experiment were confirmed by the results of numerical simulation. Thus, five different modes were considered: channel flooding, smooth film, two-dimensional waves, three-dimensional waves and film rupture. An analysis of the simulation results showed that the model qualitatively correctly reproduces all the features of the film behaviour in the studied modes. A satisfactory agreement between the calculation and experiment results was obtained in terms of the surface shape and film thickness, as well as in terms of wavelengths and ridge passing frequencies. It is shown that the calculation well reproduces in a whole the beginning of the instability development in a liquid film.