Controlling Elastic Turbulence

TL;DR

This paper shows that elastic turbulence in a viscoelastic fluid can be controlled by shear-rate modulations, with turbulence suppressed at high modulation frequencies, and identifies the critical Deborah number for transition.

Contribution

It introduces a numerical study demonstrating control of elastic turbulence via shear-rate modulations in a Taylor-Couette setup, highlighting the transition dynamics.

Findings

Elastic turbulence can be suppressed by fast shear-rate modulations.

The transition from laminar to turbulent flow is supercritical at a critical Deborah number.

Flow resistance in the laminar regime aligns with the linear Maxwell model.

Abstract

We demonstrate through numerical solutions of the Oldroyd-B model in a two-dimensional Taylor-Couette geometry that the onset of elastic turbulence in a viscoelastic fluid can be controlled by imposed shear-rate modulations. While for slow modulations elastic turbulence is still present, it vanishes for fast modulations and a laminar response with the Taylor-Couette base flow is recovered. We find that the transition from the laminar to the turbulent state is supercritical and occurs at a critical Deborah number. In the state diagram of both control parameters, Weissenberg versus Deborah number, we identify the region of elastic turbulence. We also quantify the transition by the flow resistance, which in the laminar regime we can describe within the (linear) Maxwell model.