Role of cohesion in the formation of kink wave fronts in vibrofluidized granular materials

TL;DR

This study investigates how cohesion influences the formation of kink wave fronts in vibrofluidized granular materials, revealing that cohesion enhances wave prominence and affects the conditions for wave emergence.

Contribution

It introduces a numerical analysis of cohesive interactions in granular systems and compares dry and wet granular dynamics to understand wave formation.

Findings

KWF emergence threshold aligns with specific center of mass height fluctuations.

Wet granular layers exhibit more pronounced KWFs due to cohesion.

Cohesion enhances collective motion in granular layers.

Abstract

The formation of kink wave fronts (KWFs) in a quasi-two-dimensional granular system is investigated numerically with a focus on the role of cohesive interactions between individual particles. The cohesive particle-particle interaction is achieved through tuning the velocity-dependent coefficient of restitution, based on an analytical model introduced recently. A comparison with experimental results indicates that the threshold for the emergence of traveling KWFs matches the regime in which the center of mass height of the granular layers fluctuates with a period that triples the vibration period. Further comparisons between dry and wet granular dynamics reveal that KWFs are more pronounced in wet granular layers because of enhanced collective motion induced by cohesion.