Wet Granular Materials

TL;DR

This paper reviews the mechanical properties of wet granular materials, emphasizing how liquid-induced cohesion alters their behavior, highlighting the importance of this less-studied area in various scientific and industrial contexts.

Contribution

It provides a comprehensive overview of wet granular media's mechanics and identifies open research problems in this emerging field.

Findings

Liquid presence increases cohesion between grains.

Surface angles can exceed 90 degrees in wet granular media.

Open problems suggest directions for future research.

Abstract

Most studies on granular physics have focused on dry granular media, with no liquids between the grains. However, in geology and many real world applications (e.g., food processing, pharmaceuticals, ceramics, civil engineering, constructions, and many industrial applications), liquid is present between the grains. This produces inter-grain cohesion and drastically modifies the mechanical properties of the granular media (e.g., the surface angle can be larger than 90 degrees). Here we present a review of the mechanical properties of wet granular media, with particular emphasis on the effect of cohesion. We also list several open problems that might motivate future studies in this exciting but mostly unexplored field.