Constitutive Correlations for Mass Transport in Fibrous Media Based on Asymptotic Homogenization

Area of Science:

• Materials Science
• Textile Engineering
• Chemical Engineering

Background:

• Mass transport properties of textiles are critical for various applications.
• Yarn structure, particularly fiber arrangement, significantly influences mass transfer.
• Existing correlations often assume ordered fiber distribution, potentially leading to inaccuracies.

Purpose of the Study:

• To investigate the impact of random fiber ordering on yarn mass transport properties.
• To develop improved correlations for effective diffusivity and permeability.
• To highlight the importance of considering random fiber arrangements for accurate mass transfer prediction in textiles.

Main Methods:

• Generation of random Representative Volume Elements (RVEs) for yarn structures.
• Simulation of mass transport using digital reconstruction and asymptotic homogenization.
• Derivation of new correlations based on porosity and fiber diameter.

Main Results:

• Random ordering leads to significantly lower predicted mass transfer coefficients compared to ordered models, especially at porosities below 0.7.
• The developed correlations accurately predict effective diffusivity and permeability as a function of yarn porosity and fiber dimensions.
• The approach is validated for continuous synthetic filaments with circular cross-sections.

Conclusions:

• Accurate prediction of textile mass transport requires accounting for the random arrangement of fibers within yarns.
• The developed methodology and correlations offer a more realistic estimation of mass transfer properties.
• The approach can be extended to various fiber geometries and textile structures.