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arXiv · 2204.12999

Velocity circulation intermittency in finite-temperature turbulent superfluid helium

Nicolás P. Müller·Yuan Tang·Wei Guo·Giorgio Krstulovic
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Abstract

We study intermittency of circulation moments in turbulent superfluid helium by using experimental grid turbulence and numerical simulations of the Hall-Vinen-Bekarevich-Khalatnikov model. More precisely, we compute the velocity circulation $\Gamma_r$ in loops of size $r$ laying in the inertial range. For both, experimental and numerical data, the circulation variance shows a clear Kolmogorov scaling $\langle \Gamma_r^2 \rangle \sim r^{8/3}$ in the inertial range, independently of the temperature. Scaling exponents of high-order moments are comparable, within error bars, to previously reported anomalous circulation exponents in classical turbulence and low-temperature quantum turbulence numerical simulations.

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Nicolás P. Müller, Yuan Tang, Wei Guo, Giorgio Krstulovic. 2022-04-27. Velocity circulation intermittency in finite-temperature turbulent superfluid helium. https://arxiv.org/abs/2204.12999

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