Abstract

A granular material forms a distinct and fascinating phase in physics—sand acts as a fluid as grains flow through your fingers, the fallen grains form a solid heap on the floor or may suspend in the wind like a gas.

The main challenge of studying granular materials is the development of constitutive models valid across scales, from the micro-scale (collisions between individual particles), via the meso-scale (flow structures inside avalanches) to the macro-scale (dunes, heaps, chute flows). When the particles are suspended in a fluid, forming a multiphase flow, physical laws are more complicated with additional influences and feedback effects.

In this presentation, I will introduce novel research on (1) avalanches, where we focus on the particle-particle interaction using photoelasticity, and (2) bedform dynamics, where we explore dune interaction and migration in an aqueous system.