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Updated: May 10, 2026
07:06
Methods for the Self-integration of Megamolecular Biopolymers on the Drying Air-LC Interface
Published on: April 7, 2017
Cracking condition of cohesionless porous materials in drying processes
1Research Group of Physics, Division of Natural Sciences, Faculty of Nara Women's University, Nara 630-8506, Japan. kitsune@ki-rin.phys.nara-wu.ac.jp
Summary
Cracking in soft materials during drying is modeled using an invasion percolation model. This study reveals that smaller particles, increased rigidity, and decreased heterogeneity promote cracking in drying processes.
Area of Science:
- Physics
- Materials Science
- Chemical Engineering
Background:
- Drying processes in soft materials like colloidal suspensions and granular pastes often involve air invasion.
- This air invasion typically localizes and forms cracks before bulk drying occurs.
Purpose of the Study:
- To investigate the mechanisms of air invasion and cracking in soft materials during drying.
- To develop a model predicting the conditions under which cracking initiates.
Main Methods:
- Construction of an invasion percolation model on a deformable lattice for cohesionless elastic systems.
- Derivation of a Griffith-like condition for cracking using a dimensionless parameter.
- Numerical validation of the proposed cracking condition.
Main Results:
- A dimensionless parameter characterizes the condition for cracking.
- Cracking becomes easier with smaller constituent particles.
- Increased system rigidity and decreased drying process heterogeneity also promote cracking.
Conclusions:
- The developed model provides a framework for understanding crack initiation in drying soft materials.
- The findings highlight the influence of material properties (particle size, rigidity) and process characteristics (heterogeneity) on crack formation.
- This research offers insights into controlling or preventing cracking during industrial drying operations.
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