Polymer Dynamics in Turbulent Flows

Adding even a small amount of dissolved polymer into a fluid can have a dramatic impact on the way it flows. If the flow is turbulent (high-Reynolds-number) to begin with, then the polymer can strongly modify the turbulent eddies and reduce the drag force (in flow through pipes) or even make the flow laminar. Known as the Toms effect, this phenomena is exploited to reduce the pumping costs associated with transporting oil in pipelines. Polymers can also destabilize a low-Reynolds-number steady flow and make it unsteady and chaotic. Such instabilities can produce elastic turbulence, which can greatly increase mixing in microchannels and enhance oil-recovery from underground porous reservoirs.

The source of these viscoelastic phenomena lies in the complex dynamics of individual polymer molecules: depending on the nature of the flow a polymer can get stretched-out by fluid drag forces, or alternatively relax and exert an elastic feedback on to the flow. This project aims to understand these Lagrangian dynamics of polymer molecules in turbulence, wherein the flow field fluctuates rapidly and exerts strong straining forces on the polymers. The project will involve combining brownian dynamics (BD) and computational fluid dynamics (CFD) simulations to explore issues at the frontier of this exciting field.

For more information: https://www.che.iitb.ac.in/group/picardo-group/article/turbulent-transport

Collaborators:

Dario Vincenzi, Univ. Cote D'Azur, Nice, France (https://math.unice.fr/~vincenzi/).

Prabhakar Ranganathan, Monash University, Australia (https://www.monash.edu/engineering/prabhakarranganathan)