Stability of vertical films of molten glass due to evaporation

Franck Pigeonneau (1) , Helena Kočárková (1) , Florence Rouyer (2)

1 SVI - Surface du Verre et Interfaces
2 navier umr 8205 - Laboratoire Navier

This work presents a theoretical model to study the gravitational drainage of a vertical molten glass film. Surface tension gradient due to the evaporation of sodium oxide from the interfaces is taken into account using a simple model with a surface tension function of the liquid film thickness. A lubrication model is derived taking into account the gradient of surface tension. The final system of equations describing the mass and the momentum conservations is numerically solved by an implicit time solver using a finite difference method at a second order in time and space. The numerical method is compared with a previous results obtained without surface tension gradient. Afterward, the numerical procedure is applied to study a film drainage of molten silica-soda-lime glass. The effect of the surface tension gradient is investigated: it is pointed that with an increase of 0.5 % of the surface tension over the spread of the film which is order of few centimeters, the liquid film reaches an equilibrium thickness in agreement with previous experimental work.

Mots clés: film drainage; Trouton model; molten glass; high viscous fluid; evaporation

Domaines: Génie des procédés; Matériaux; Mécanique [physics.med-ph]; Milieux fluides et réactifs

Franck Pigeonneau, Helena Kočárková, Florence Rouyer. Stability of vertical films of molten glass due to evaporation. International Conference on Multiphase Flow, May 2013, Jeju, South Korea. ⟨hal-01519293⟩