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arXiv · 2303.06631

Higher-order statistics and intermittency of a two-fluid HVBK quantum turbulent flow

Zhentong Zhang·Ionut Danaila·Emmanuel Lévêque·Luminita Danaila
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Abstract

The Hall-Vinen-Bekharevich-Khalatnikov (HVBK) model is widely used to numerically study quantum turbulence in superfluid helium. Based on the two-fluid model of Tisza and Landau, the HVBK model describes the normal (viscous) and superfluid (inviscid) components of the flow using two Navier-Stokes type equations, coupled through a mutual friction force term. This feature makes the HVBK model very appealing in applying statistical tools used in classical turbulence to study properties of quantum turbulence. A large body of literature used low-order statistics (spectra, or second-order structure functions in real space) to unravel exchanges between the two fluids at several levels. The novelty in this study is to use a theoretical approach based on first principles to derive transport equations for the third-order moments for each component of velocity.

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Zhentong Zhang, Ionut Danaila, Emmanuel Lévêque, Luminita Danaila. 2023-03-12. Higher-order statistics and intermittency of a two-fluid HVBK quantum turbulent flow. https://doi.org/10.1017/jfm.2023.235

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