Motion of vortex ring with tracer particles in superfluid helium

TL;DR

This paper derives equations of motion for vortex rings with tracer particles in superfluid helium to assess how particles influence vortex dynamics, addressing concerns about visualization techniques altering turbulence observations.

Contribution

It introduces a quantitative criterion to evaluate the impact of tracer particles on vortex motion in superfluid helium, enhancing understanding of visualization effects.

Findings

Derived equations of motion for vortex rings with trapped particles

Established a criterion to assess particle influence on vortex dynamics

Applied the criterion to recent experimental data

Abstract

Recent experiments on quantum turbulence in superfluid helium made use of small tracer particles to track the motion of quantized vortices, determine velocity statistics and visualize vortex reconnections. A problem with this visualization technique is that it may change the turbulent flow which it visualizes. To address this problem, we derive and solve the equations of motion of a quantized vortex ring which contains a given number of particles trapped on the vortex core, hence derive a quantitative criterion to determine in which measure small particles trapped in quantized vortices affect vortex motion. Finally we apply the criterion to a recent experiment.