Physics Colloquium: Clogging: The self-sabotage of suspensions flows

Prof. Alban Sauret, UC Santa Barbara

Abstract:

From pipes to highways to arteries, stopping the flow is always inconvenient and sometimes dangerous. Clogging can occur whenever a suspension, comprised of discrete particles dispersed in a liquid, flows through a confined geometry. It is a major issue in many engineering systems, such as filtration devices, additive manufacturing, or in bioengineering. In this talk, I will discuss the role of the different clogging mechanisms and our recent efforts to characterize, model, and prevent – or at least delay – the clogging of fluid systems.

First, I will consider clogging by bridging: the formation of a stable arch of particles at a constriction. I will show that clogging by bridging is primarily controlled by the constriction width and the volume fraction of the suspension. Second, I will demonstrate how pulsatile flows can help mitigate clogging by aggregation of colloidal particles when compared to steady flows in microfluidic systems. Finally, I will show new filtration methods for particles of different sizes that rely on interfacial effects and that are less prone to clogging than conventional filters. Even if clogging always occurs in a fluid system, understanding the mechanisms and conditions of clog formation can lead to new design principles and improve the reliability of multiple engineering systems.

Bio: Alban Sauret is an Associate Professor in the Department of Mechanical Engineering at UC Santa Barbara. He graduated with a BS and an MS in Physics from ENS Lyon and earned a Ph.D. in Mechanical Engineering from the University of Aix-Marseille in 2013. He worked as a Postdoctoral Fellow at Princeton University with Howard Stone from 2013 to 2014. He then spent four years as a tenured CNRS Research Scientist in the National Institute of Physics (INP) and a visiting research scholar at NYU Tandon School of Engineering. He joined UC Santa Barbara in 2018. His research lies at the intersection of fluid mechanics and soft matter, as it aims to understand the dynamics of multiphase systems. Alban Sauret was named a Soft Matter Emerging Investigator and elected a UC Regents Junior Faculty Fellow. He has received the NSF CAREER Award in 2020, the APS Milton van Dyke award, and the APS DSOFT Gallery of Soft Matter Award. His research has been featured in various media outlets such as the Los Angeles Times, the Wall Street Journal, and Science Friday.