Polymers in Fluid Flows

TL;DR

This paper reviews how flexible polymers affect fluid flows, including phenomena like drag reduction and elastic turbulence, primarily based on numerical simulations over the past two decades.

Contribution

It synthesizes current understanding of polymer-fluid interactions, highlighting mechanisms and explaining experimental observations through numerical simulations.

Findings

Numerical simulations qualitatively explain experimental phenomena.

Disentangling mechanisms underlying polymer effects in flows.

Comparison of different theoretical approaches.

Abstract

The interaction of flexible polymers with fluid flows leads to a number of intriguing phenomena observed in laboratory experiments, namely drag reduction, elastic turbulence and heat transport modification in natural convection, and is one of the most challenging subjects in soft matter physics. In this paper we review our present knowledge on the subject. Our present knowledge is mostly based on direct numerical simulations performed in the last twenty years, which have successfully explained, at least qualitatively, most of the experimental results. Our goal is to disentangle as much as possible the basic mechanisms acting in the system in order to capture the basic features underlying different theoretical approaches and explanations.