Test Master Calendar (OCR)

Abstract:
Erosion is often controlled by unsteady and highly nonuniform flows near surfaces. This situation arises, for example, when a jet or the wake of a moving body interacts with a granular bed. In this talk, we will see how simple laboratory model systems can isolate the mechanisms governing the onset of erosion and grain transport.

In the first part, inspired by the way some fish are able to bury themselves in sand by flapping their fins, we will discuss erosion induced by the flow generated by a disk translating or oscillating near a granular bed. This configuration combines squeeze flow, suction flow, and vortex-ring impact, which together determine the erosion threshold. In the second part, we will turn to cohesive sediments. Using a model granular material with tunable interparticle cohesion, we will consider how cohesion modifies erosion thresholds, crater formation, and particle transport under an impinging turbulent jet. These results can be organized using a cohesive Shields number, which helps connect grain-scale physics to engineering-scale predictions.
 
Bio:
Alban Sauret is Associate Professor and Clark Faculty Fellow in the Department of Mechanical Engineering at the University of Maryland, College Park. His research focuses on fluid mechanics, soft matter, interfacial dynamics, and granular physics, with broad applications in environmental processes, advanced manufacturing, and energy systems. He received his BS, MS, and PhD in Physics in France. Before joining Maryland, he was a postdoctoral researcher at Princeton University, a CNRS research scientist in France, and a faculty member at UC Santa Barbara. His honors include the NSF CAREER Award, the APS Milton van Dyke Award, and the ASME Rising Star of Mechanical Engineering Award. He was also named a Gordon and Betty Moore Foundation Experimental Physics Investigator.