Wicking dynamics in yarns

Area of Science:

• Materials Science
• Physics of Fluids
• Textile Engineering

Background:

• Spontaneous liquid imbibition, or wicking, in porous media like textiles and yarns can exhibit complex behaviors.
• Existing models often fail to capture the unique wicking dynamics observed in yarns.

Purpose of the Study:

• To investigate the underlying mechanisms of step-wise wicking dynamics in yarns.
• To determine the primary factors governing wicking behavior in yarn structures.

Main Methods:

• Utilized fast X-ray tomographic microscopy to visualize pore-scale processes.
• Employed neutron radiography for macroscopic water uptake analysis.
• Developed a semi-empirical pore network model incorporating experimental data.

Main Results:

• Yarn pore networks are characterized by sparse, long, and narrow pores, leading to step-wise uptake.
• Wicking involves rapid pore filling (seconds) interspersed with significant waiting times (minutes) during pore navigation.
• Key wicking events and pore network topology critically influence macroscopic water uptake.

Conclusions:

• Wicking dynamics in yarns are primarily governed by pore-to-pore transition times and the intricate pore network structure.
• Accurate modeling requires consideration of waiting times between pore transitions and the overall network topology.
• Understanding these factors is crucial for explaining and predicting wicking behavior in textile materials.