Soft Matter & Fluid Mechanics
What we do
We describe processes at the nano and micron scales that arise in soft matter & fluid mechanics. This work is usually driven by as yet unexplained experimental results whose fundamental origin we clarify by developing mathematical and computational models; we employ perturbation methods, asymptotic analysis, dynamical systems theory, PDEs etc., we collaborate with experimentalists and we also invent new physical effects not yet met in experiment.
Current directions are in active matter for materials, the life sciences and energy. For instance, flux-charge ion electrokinetics for iontronics applications. Magnetism and magnetic materials for the destruction of malignant cells.
For more action and less talk, visit my research page or my publications page chronologically or by subject.
Academic Experience
Northwestern University, Evanston, IL USA, Research Associate Materials Science & Engineering, Contractor for the Center for Computation & Theory of Soft Materials (working with Monica Olvera de la Cruz)
Imperial College London, London UK, Research Associate in Complex and Multiscale Systems
University of Washington, Seattle WA USA, Postdoctoral Research Associate in Condensed Matter Physics (working with Anton V. Andreev and Boris Z. Spivak)
Northwestern University, Evanston, IL USA, Golovin Assistant Professor of Applied Mathematics (working with Stephen H. Davis)
Career break 2016-2021
Visits
Michigan State University, East Lansing MI USA, Mechanical Engineering (Visiting Thomas J. Pence)
Northwestern University, Applied Mathematics & Engineering Sciences, Evanston IL USA, (Visiting Stephen H. Davis)
University of Washington, Physics, Seattle WA USA, (Visiting Anton V. Andreev and Boris Z. Spivak)
Education
Ph.D (Dec 16, 2011): Applied Mathematics University of Washington, Seattle, WA USA . Thesis description. Advisor. Robert E. O'Malley, Jr. (also working with Anton V. Andreev and Boris Z. Spivak on hydrodynamics and condensed matter field theory).
Part III Applied Mathematics & Theoretical Physics University of Cambridge, Cambridge UK
Selected Publications
'Evanescent and inertial-like waves in rigidly-rotating odd viscous liquids' Journal of Fluid Mechanics, 996: A13 (2024) E.Kirkinis & M. Olvera de la Cruz Cartoons
'Taylor columns and inertial-like waves in a three-dimensional odd viscous liquid' Journal of Fluid Mechanics, 973: A30 , (2023) E.Kirkinis & M. Olvera de la Cruz
"Thermocapillary Migrating Odd Viscous Droplets" Physical Review Letters 131, 198201 (2023) A. Aggarwal, E. Kirkinis, & M. Olvera de la Cruz. Cartoons.
Selected Preprints
'Universal behavior in traveling wave electroosmosis'. A. Shrestha, E.Kirkinis & M. Olvera de la Cruz arXiv:2401.15426 (for a description and a cartoon see here)
'Self-generated electrokinetic flows from active-charged boundary patterns ' A. Shrestha, E.Kirkinis & M. Olvera de la Cruz arXiv:2412.15397 (for a description and a cartoon see here)
Experiment with low frequency rotating magnetic field on a hydrophobic slide; contact lines overcome contact angle hysteresis and become unpinned leading to migration. 'Wobbling and Migrating Ferrofluid Droplets', Communications Physics 7, 385 (2024) Videos
Simulation; Finite element simulations demonstrating the migration of a 2D droplet due to the wobbling motion of the liquid-gas interface. The magnetic field is rotating clockwise at 10 Hz.
Computational model; Droplet migrates in an opposite sense to the orientation of the magnetic field (rotating clockwise)
Experimental method; Migration of the droplet was induced using an external magnetic field of 100 G rotating at 10 Hz.
Experiment: droplet can be induced to travel up or down inclined planes, clean surface impurities, harvest materials, and transport matter to desired locations. Place a small cube of a soft PEGMEA-based hydrogel (cargo) near the droplet at the bottom of a curved Teflon substrate. Droplet climbs uphill with a magnetic field of 125 G rotating counterclockwise at 10 Hz until the droplet overruns the cargo. It pick up and moves the cargo along with it. We then flip the direction of the field rotation to clockwise causing the droplet and cargo to move downhill
Center for Computation & Theory of Soft Materials McCormick School of Engineering & Applied Science, Northwestern University Technological Institute 2145 Sheridan Road, Evanston, IL 60208 USA Email: lastname@northwestern.edu
Throttle-induced stability of roller motion in anisotropic environments
Header Image: Chicago skyline taken from Promontory Point, Lakefront Trail, Chicago, IL 60615, United States of America. Photograph by Eleftherios Kirkinis.