Drying in a microfluidic chip: experiments and simulations.

Area of Science:

• Physics
• Engineering
• Material Science

Background:

• Drying of porous media is crucial in various industrial processes.
• Understanding fluid dynamics in disordered porous structures is complex.

Purpose of the Study:

• To develop and validate an experimental microfluidic model for drying porous media.
• To compare drying patterns and rates between experiments and a pore-network model under varying disorder levels.

Main Methods:

• Utilized microfluidic cells with pillar arrays to create a porous medium.
• Introduced disorder by randomizing pillar radii.
• Performed horizontal drying experiments excluding gravitational effects.
• Developed a matching two-dimensional pore-network model for simulations.

Main Results:

• Experimental and simulated drying patterns showed good agreement in geometrical features.
• The model initially under-predicted the formation of trapped fluid clusters.
• Drying rates were challenging to reproduce but improved with the inclusion of trapped clusters in the model.

Conclusions:

• The microfluidic pore-network model provides a valuable tool for studying drying in porous media.
• The study highlights the importance of accounting for trapped fluid clusters in drying models.
• The developed methodology is adaptable for various multi-phase flow problems and micro-model development.