par Scheid, Benoît 
;Kabov, Oleg ;Minetti, Christophe ;Colinet, Pierre ;Legros, Jean Claude
Editeur scientifique Hahne, E. W. P.;Heidemann, W.;Spindler, K.
Référence (Heidelberg), Proc. 3rd Eur. Thermal-Sci. Conf., Vol. 2, page (651-657)
Publication Publié, 2000
;Kabov, Oleg ;Minetti, Christophe ;Colinet, Pierre ;Legros, Jean Claude Editeur scientifique Hahne, E. W. P.;Heidemann, W.;Spindler, K.
Référence (Heidelberg), Proc. 3rd Eur. Thermal-Sci. Conf., Vol. 2, page (651-657)
Publication Publié, 2000
Publication dans des actes
| Résumé : | The surface thermocapillary effect is studied for a thin liquid film falling on a vertical plate and locally heated, leading to the formation of a horizontal bump. A reflectance-schlieren method was developed to facilitate accurate measurement of the relative film thickness by measuring the slope of the surface. The experiments were performed for two non-evaporative ethyl alcohol aqueous solutions (10% and 25%). A fluid circulation system produced steady films at constant mass flux. Data are presented for film thickness profiles as function of the liquid Reynolds number and the heat flux density. The results show that the reflectance-Schlieren method is totally appropriate for high accuracy measurement and for a large range of surface deformation (up to 3 degrees). Extended analysis is presented for vertical rivulets appearing above a critical heat flux threshold for which the above-mentioned bump becomes unstable. As the deformations become bigger and the flow structure has to be considered in three-dimensions, recommendations are made in order to realise measurements under those new conditions. |
