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arXiv · 2208.12329

Vorticity Locking and Pressure Dynamics in Finite-Temperature Superfluid Turbulence

Jason Laurie·Andrew W. Baggaley
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Abstract

We present a numerical study of finite-temperature superfluid turbulence using the vortex filament model for superfluid helium. We examine the phenomenon of vorticity locking between the normal and superfluid components across a wide range of temperatures, using two different structures of external normal fluid drive. We show that vorticity locking increases with temperature leading to the superfluid flow being more influenced by the characteristics of the normal fluid. This also results in stronger superfluid polarization and turbulent intermittency. We also examine how these properties influence the pressure field and attempt to verify a long-standing $P_k\propto k^{-7/3}$ theoretical quantum signature within the spatial pressure spectrum.

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Jason Laurie, Andrew W. Baggaley. 2022-08-25. Vorticity Locking and Pressure Dynamics in Finite-Temperature Superfluid Turbulence. https://doi.org/10.1103/physrevfluids.8.054604

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