Contact line motion on heated patterned surfaces

Abstract

We develop a lubrication-type model of contact line motion on a surface patterned by an array of square patches of decreased wettability. The model accounts for evaporation of the liquid due to surface heating, as well as effects of surface tension and disjoining pressure. Stick-slip motion and strong interface deformations are found from the simulations. The height of the capillary ridge becomes spatially nonuniform when the stable contact line travels over the region of decreased wettability. Coupling between the surface pattern and intrinsic contact line instability is investigated. For the weak evaporation limit, the model predictions are compared to previous studies of contact line dynamics under isothermal conditions.

Keywords:

• Contact angle
• disjoining pressure
• evaporation
• surface patterns
• viscous flow

Additional information

Funding

The work on development of the contact line models was supported by the Russian Science Foundation (Project No. 19-19-00695). The work on numerical implementation was funded by RFBR and Novosibirsk region, project number 20-48-540027.