Velocity Distributions of Tracer Particles in Thermal Counterflow in Superfluid $^4$He

TL;DR

This paper models and simulates the behavior of tracer particles in superfluid helium to understand quantum turbulence, successfully matching experimental velocity distribution data.

Contribution

It introduces a coupled dynamics model of particles and vortices in superfluid helium and validates it through numerical simulations that align with experimental results.

Findings

Numerical simulations agree with experimental velocity distributions.

The coupled dynamics model captures key features of particle motion.

Results enhance understanding of quantum turbulence in superfluid helium.

Abstract

Quantum turbulence accompanying thermal counterflow in superfluid $^4$He was recently visualized by the Maryland group, using micron-sized tracer particles of solid hydrogen (J. Phys. Soc. Jpn. {\bf 77}, 111007 (2008)) . In order to understand the observations we formulate the coupled dynamics of fine particles and quantized vortices, in the presence of a relative motion of the normal and superfluid components. Numerical simulations based on this formulation are shown to agree reasonably well with experimental observations of the velocity distributions of the tracer particles in thermal counterflow.