Chiral Particles in Taylor-Couette Turbulence

TL;DR

This study explores how chiral particles behave in turbulent Taylor-Couette flow at high Reynolds numbers, revealing flow-dominated dynamics with no significant difference between left- and right-handed particles.

Contribution

First experimental investigation of chiral particle translation and rotation in high Reynolds number turbulent Taylor-Couette flow, analyzing flow-particle interactions and symmetry effects.

Findings

Chiral particles follow Taylor vortices closely.

No difference in rotation dynamics between chiralities.

Flow vorticity governs particle behavior.

Abstract

This work investigates chiral particles, which break mirror symmetry, in turbulent Taylor--Couette flow. These particles generally display a translation-rotation coupling moving through a quiescent fluid. Here we performed experiments using large chiral particles (typical size \unit{5}{mm}) in turbulent Taylor--Couette flow, for Reynolds numbers $9\cdot10^3 \leq \text{Re} \leq 1.5 \cdot 10^5$. The density-matched chiral particles are studied in a dilute regime $(\phi = 1.7 \cdot 10^{-4})$, where their location and orientation are tracked over time to investigate the particle-fluid coupling. We investigate whether the translation-rotation coupling observed at low Reynolds numbers is still observable over the measured high Reynolds numbers, using the tracked location and orientation. Similarly, we verify whether the chiral particles display a preferred location or orientation, and whether the left-handed and right-handed particles show different rotation statistics. The location data show that the chiral particles closely follow the structure of Taylor vortices. Hence, the orientation data and rotation data of the chiral particles are split between the Taylor vortices and particle chiralities. The results show no difference in rotation and orientation dynamics between chiralities. Rather, the particle dynamics are flow-dominated, where the flow vorticity determines the specific particle dynamics.