Harnessing Geometry and Nonlinearity to Shape Particulate Flows

Departments: Mechanical Engineering and Materials Science
Time: Friday, February 17, 2023 - 3:00pm - 4:00pm
Type: Seminar Series
Presenter: Bhargav Rallabandi; Riverside, Assistant Professor. University of California
Room/Office: Room 107
Location:
Mason Lab
9 Hillhouse Avenue
New Haven, CT 06511
United States
See map: Google Maps

Department of Mechanical Engineering and Materials Science Seminar

Bhargav Rallabandi
Assistant Professor
University of California, Riverside

"Harnessing Geometry and Nonlinearity to Shape Particulate Flows"

Abstract: The flow of liquids carrying suspended materials is important in many natural and engineered systems, with examples in microfluidic, biological, and environmental contexts. In this talk, I will discuss how nonlinear interactions between fluid flow, suspended particles and their confining environment can be harnessed to produce a range of useful flow phenomena. In the first part of the talk, I will describe the motion of suspended particles confined by compliant boundaries – the particles create a flow that deforms the boundary, which in turn feeds back onto particle motion. This interaction produces a spontaneous lift of the particles away from the soft surface, which we understand through experiments and theory.  I will then discuss some implications of these effects for the rheometry and tribology of soft materials. In the second half of the talk, I will discuss how oscillatory excitations of a fluid can be rectified to produce powerful steady flows in microfluidic channels. I will show that a nonlinear interplay between viscous and inertial forces can be utilized to sort suspended particles based on their size. Finally, I will discuss recent work demonstrating how the topology of these flows is drastically altered by geometric confinement – in particular, we will see that confining the system along one dimension makes the flow more three-dimensional, not less.

Bio: Bhargav Rallabandi is an Assistant Professor of Mechanical Engineering at the University of California, Riverside. He received his Ph.D. in Theoretical and Applied Mechanics from the University of Illinois at Urbana-Champaign, studying flows driven by oscillating microbubbles. He then joined Princeton University as a postdoctoral researcher, where he worked on fluid-elastic interactions and on the flow of sea ice in straits. His current research interests include interactions of fluid flows with acoustic fields and soft materials, as well as stochastic particle-based models for sea ice dynamics. He is the recipient of a 2020 Hellman Fellowship and a 2022 NSF CAREER award.

February 17 at 3:00pm in Mason 107