ChBE Seminar Series: The fluid dynamics of buckled filaments and viscous interfaces
Speaker: Harishankar Manikantan, Assistant Professor, Chemical Engineering; University of California, Davis
Title: The fluid dynamics of buckled filaments and viscous interfaces
Dr. Harishankar Manikantan will present recent efforts in mathematics modeling the unique dynamics of complex particulate fluid flows in two systems. First, he will illustrate the rich and nonlinear dynamics that arise when microscale elastic filaments are subjected to flow. Such an interplay of hydrodynamic, elastic and Brownian forces is central to cytoskeletal portions of the cell, the locomotion of microbes, and mucal transport. Using a combination of theory and simulations, he will illustrate mechanisms behind biopolymer buckling in microfluidic geometries, unique transport patterns of microtubules in motility assays, and collective effects in the sedimentation of a fibrous suspension.
Following this, Dr. Manikantan will describe a different class of multiphase flows — that of surfactant-laden interfaces that are vital to industrial coatings, foams, emulsions and physiological interfaces like lung alveoli and the tear film. In particular, he will describe the unique ways in which a ‘surface viscosity’ might affect some of these flows. He will illustrate toy models — inspired by recent experiments— that result in novel features in interfacial flows with a nontrivial surface viscosity. Interfaces can ‘choke’ if the surface viscosity increases locally with added surfactant, and particles trapped on a mono/bi-layer can segregate or separate solely due to the hydrodynamics of these systems. These models offer unique engineering strategies to stabilize multiphase fluids or phase separate interfacial inclusions.
Harishankar Manikantan received his master's in Theoretical and Applied Mechanics from the University of Illinois at Urbana-Champaign (2012) and Ph.D. in Applied Mechanics from the University of California, San Diego in 2015. After graduation, he worked as a postdoctoral researcher at UC Santa Barbara for three and a half years. Since summer 2019, he has been an assistant professor of chemical engineering at UC Davis. His research interests are complex fluids, soft matter, and the mathematical modeling of microscale transport phenomena.