In this talk, I will describe two different examples of how we investigate heterogeneous transport in porous media.
- First, I will describe how we study the drying of shrinkable, granular materials—materials composed of hydrated grains that individually shrink when dried. Prominent examples include clays, soils, biological tissues, foods, and gel coatings. In many cases, these materials crack during drying, critically hindering applications. By combining experiments, discrete-element simulations, and poroelasticity theory, we reveal how grain shrinkability dramatically alters crack evolution during drying—in some cases, even causing cracks to spontaneously self-heal. Our work helps to elucidates the rich physics underlying cracking, and yields new strategies to controlling crack evolution and patterning.
- Second, I will describe how we study bacterial migration in porous media. Diverse applications, ranging from bioremediation to drug delivery, rely on this process; however, how pore-scale confinement alters bacterial motility is unknown. Using a novel experimental platform, we demonstrate that the paradigm of run-and-tumble motility is dramatically altered in a porous medium. Instead, we find a new form of motility in which individual cells are intermittently and transiently trapped as they navigate the pore space; analysis of these dynamics enables prediction of bacterial transport over large length and time scales. Additionally, we show how concentrated populations can collectively migrate through a porous medium—despite being strongly confined. This work thus provides a revised picture of bacterial motility in complex media, with implications for healthcare, agriculture, and bioremediation.
BRIEF ACADEMIC/EMPLOYMENT HISTORY:
Sujit Datta is an Assistant Professor of Chemical and Biological Engineering at Princeton University. He is also Associated Faculty at the Andlinger Center for Energy & the Environment, the Princeton Institute for the Science & Technology of Materials, and the Princeton Environmental Institute. He earned a BA in Mathematics and Physics and an MS in Physics in 2008 from the University of Pennsylvania. He earned his PhD in Physics in 2013 from Harvard, where he studied fluid dynamics and instabilities in porous media and colloidal microcapsules with David Weitz. His postdoctoral training was in Chemical Engineering at Caltech, where he studied the biophysics of the gut with Rustem Ismagilov. He joined Princeton in 2017, where his lab (dattalab.princeton.edu) studies soft and active materials in complex settings, motivated by challenges like clean oil/gas recovery, effective water remediation, and targeted drug delivery. Prof. Datta is the recipient of the LeRoy Apker Award from the American Physical Society, the Andreas Acrivos Award in Fluid Dynamics from the American Physical Society, the ACS Petroleum Research Fund New Investigator Award, the Alfred Rheinstein Faculty Award, and multiple Princeton Engineering Commendations for Outstanding Teaching.
MOST RECENT RESEARCH INTERESTS:
We study soft materials, with a focus on four areas:
(i) Multi-phase flow in porous rocks—how do structural heterogeneities and fluid rheology impact flow behavior?
(ii) Extreme mechanics of soft, porous materials—how can osmotic stresses be used to control deformations in gels?
(iii) Soft matter physics in the body—how do the physico-chemical properties of mucus alter transport through it?
(iv) Emergent behaviors of bacterial communities—how does confinement in porous media alter bacterial behavior?