Dr. Patrick Underhill, Professor & Associate Head
Department of Chemical and Biological Engineering
Rensselaer Polytechnic Institute

Self-assembly and dynamics of particles suspended in fluids

Abstract:
Many simulation techniques exist for the simulation of particles in fluids, ranging from atomistic models for small lengths and fast motions to continuum constitutive equations for large lengths and slow motions. In this talk, I will describe the use of two intermediate-level simulation techniques. The first approach uses vertex models, which divides space into 3D polyhedra (or polygons in 2D thin films). The polyhedra represent packings of squishy particles such as micelles. We have used this model to understand how a liquid disordered system creates an ordered structure when the temperature is quenched. The second approach uses a stochastic field theory. Continuum transport equations keep track of a concentration field of chemicals or particles instead of the positions of every particle. If the number of particles in a region is small enough, fluctuations in concentration can be important. We have used this approach to understand correlations within concentrated electrolytes and phase stability of solutions.

Bio:
Patrick Underhill is Professor and Associate Head of Chemical and Biological Engineering at Rensselaer Polytechnic Institute. He received a B.S. in Chemical Engineering and a B.S. in Physics in 2001 from Washington University, St. Louis. He then received a Ph.D. in Chemical Engineering from MIT in 2006 advised by Patrick Doyle. After postdoctoral research at the University of Wisconsin, Madison with Michael Graham, he began as an Assistant Professor at Rensselaer in 2008. Patrick’s research interests are in theory, simulation, and experiments of complex fluids, especially polymers, colloids, active matter, and combinations of these. In 2013, he received the Arthur B. Metzner Early Career Award from the Society of Rheology. In addition to research, Patrick has received three teaching awards from Rensselaer.