Grid superfluid turbulence and intermittency at very low temperature

TL;DR

This paper uses numerical simulations of the Gross-Pitaevskii equation to study turbulence and intermittency in low-temperature superfluid flows, revealing universal statistical features similar to classical fluids.

Contribution

It demonstrates the universality of turbulence statistics in superfluid flows and compares them with classical turbulence, highlighting intermittency and Kolmogorov-like behavior.

Findings

Velocity increments are skewed in turbulent states.

Statistics are universal across different flow types.

Kolmogorov constant close to classical fluids.

Abstract

Low-temperature grid generated turbulence is investigated by using numerical simulations of the Gross-Pitaevskii equation. The statistics of regularized velocity increments are studied. Increments of the incompressible velocity are found to be skewed for turbulent states. Results are later confronted with the (quasi) homogeneous and isotropic Taylor-Green flow, revealing the universality of the statistics. For this flow, the statistics are found to be intermittent and a Kolmogorov constant close to the one of classical fluid is found for the second order structure function.