Dynamic Phase Alignment in Navier-Stokes Turbulence

Abstract

In Navier-Stokes turbulence, energy and helicity injected at large scales are subject to a joint direct cascade, with both quantities exhibiting a spectral scaling $\propto k^{-5/3}$. We demonstrate via direct numerical simulations that the two cascades are compatible due to the existence of a strong scale-dependent phase alignment between velocity and vorticity fluctuations, with the phase alignment angle scaling as $\cos {\alpha }_k\propto k^{-1}$.

References in corpus (4)

• Spectral Modeling of Turbulent Flows and the Role of Helicity
• Inverse cascade of energy in helical turbulence
• Helicity statistics in homogeneous and isotropic turbulence and turbulence models
• A closure theory for the split energy-helicity cascades in homogeneous isotropic homochiral turbulence

Cited by in corpus (1)

• Helical Fluid and (Hall)-MHD Turbulence: a Brief Review