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arXiv · 1601.07697

Simulation of capillary infiltration into packing structures by the Lattice-Boltzmann method for the optimization of ceramic materials

Abstract

In this work we want to simulate with the Lattice-Boltzmann method in 2D the capillary infiltration into porous structures obtained from the packing of particles. The experimental problem motivating our work is the densification of carbon preforms by reactive melt infiltration. The aim is to determine optimization principles for the manufacturing of high-performance ceramics. Simulations are performed for packings with varying structural properties. Our analysis suggests that the observed slow infiltrations can be ascribed to interface dynamics. Pinning represents the primary factor retarding fluid penetration. The mechanism responsible for this phenomenon is analyzed in detail. When surface growth is allowed, it is found that the phenomenon of pinning becomes stronger. Systems trying to reproduce typical experimental conditions are also investigated. It turns out that the standard for accurate simulations is challenging. The primary obstacle to overcome for enhanced accuracy seems to be the over-occurrence of pinning.

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Danilo Sergi, Loris Grossi, Tiziano Leidi, Alberto Ortona. 2016-07-27. Simulation of capillary infiltration into packing structures by the Lattice-Boltzmann method for the optimization of ceramic materials. https://doi.org/10.1080/19942060.2016.1189361

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