THERMOCAPILLARY BREAKDOWN OF FALLING LIQUID-FILMS AT HIGH REYNOLDS-NUMBERS

This paper presents a new correlation in which the heat flux required to break a falling liquid film can be determined from the film Reynolds number. The correlation is based on the balance of local forces in the substrate region for high-Reynolds number films. Validation of the correlation required experimental data for breakdown of wavy liquid films at a significantly higher Reynolds number and heat flux than have been presented in the past. These data are also presented in the paper. The results show that the correlation collapses the experimental data for three liquids with widely varying physical properties at film Reynolds numbers at up to about 10(4). This correlation gives one the ability to predict the thermocapillary breakdown of wavy falling films at high Reynolds number, high heat flux, and over a wide range of fluid properties.