Role of Thermocapillary Convection in Rupture of a Falling Liquid Film Heated From Below

The present work is aimed to describe and explain the physical mechanism of the rupture of a liquid film of moderate thickness falling down a heated substrate. Our investigations are based on the experimental data obtained using IR thermography, fiber optical technique as well as theoretical estimation of critical values. We show that thermocapillary convection may be responsible for critical film thickness. By investigating the instability of thermocapillary cells we demonstrate that thermocapillary forces play a dominant role in the first and the second stages of the dry patch formation process.