Interaction of Elasto-inertial Turbulence and material microstructure – INTER-ET

Introduction

Transport and handling of complex fluids is an important contributor to world energy consumption (10% is estimated to come from pumping suspensions). Improving their mixing and heat transfer is key for new applications from process industry to medicine. A tiny amount of polymers, making the fluid viscoelastic, can completely change its flow, reducing turbulent friction and pumping power by around 70% at large scales, but creating a whole new kind of turbulence at small scales.

Elastic Turbulence

Elastic turbulence has recently received exponentially increasing attention as a promising way to increase mixing and heat transfer at small scales (e.g., lab-on-a-chip applications). It also plays a role in efficient cleaning and storage of fluids in the ground, but can be an undesired source of chaotic flow paths and friction (e.g., cell sorting, blood flow).

Knowledge Gaps

However, large gaps exist in understanding elastic and elasto-inertial turbulence, particularly between conflicting experiments and theories, and the multiscale interactions needed to sustain it.

Project Overview

The INTER-ET proposal will revolutionize the state-of-the-art understanding of elastic fluids turbulence and its interaction with material microstructure through synergetic simulations and experiments that were impossible until now.

Methodology

This will be achieved by our high-fidelity methods that for the first time enabled:

1. Three-dimensional studies of elastoviscoplastic fluid turbulence.
2. Suspensions of tens of thousands of particles.
3. Experimental time-resolved measurements on microscale.

Theoretical Framework

Theories for Newtonian turbulence do not hold for elastic fluids, and there is an urgent need for improved theories and models in wall-bounded turbulence of complex fluids.

Objectives

The INTER-ET proposal aims to: i) Perform the first simulations and experiments of EIT in matching wall-bounded geometries.
ii) Apply methods for direct experimental measurement of time-resolved stress fields and compare with simulations.
iii) Improve microscopic models and predictions of elastic instability and turbulence.