Title: Bridging ‘Micro-‘ and ‘Macroscopic’ Scales in Wet Granular Dynamics

Abstract: “From sand dunes to Faraday crispation, granular materials (i.e., large agglomerations of macroscopic particles) are ubiquitous in nature, industry and our daily lives with widespread applications from the prediction of natural disasters (e.g. snow avalanches and debris flows) through the enhancement of energy efficiency in industries (e.g. mining, civil engineering) to emerging new technologies (e.g. powder based additive manufacturing, or 3D printing). Due to the energy dissipation at the individual particle level, granular systems are highly dissipative and consequently their stationary states are typically far from thermodynamic equilibrium. Therefore, understanding how the interactions between individual particles influence the collective behavior is crucial in describing granular materials as a continuum.

In this talk, our efforts in deciphering the dynamics of partially wet granular materials (e.g., we sand for sculpturing) will be presented. From single particle bouncing to collective motion, the following questions will be addressed. At the `microscopic’ level of individual particles: How to estimate the energy dissipation associated with the impact of wet particles and consequently predict the coefficient of restitution? Stepping further to ‘macroscopic’ scale, pattern formation scenario in vibrofluidize wet granular layer will be presented and the link to ‘microscopic’ particle-particle interactions will be elucidated. If time allows, I will provide a brief overview of experimental approaches enabling us to ‘see through’ granular materials for investigating granular dynamics.”

Host: Karen Daniels