Direct numerical simulation data of velocity- and vorticity-fluctuations are used to study the Coriolis-induced modulation of spectral-scales, spatiotemporal correlations, and vorticity-dynamics in turbulent channels. Although rotation-induced asymmetry is known, its scale-resolved manifestation and link between spectral-dynamics and local vortex-topology remain unclear. Energy spectra show a spectral shift toward larger scales and increased energy on the anti-cyclonic side, consistent with the emergence of large-scale structures, while energy is suppressed on the cyclonic side. Dissipation becomes asymmetric, but the characteristic small scales of dissipation are nearly unaffected by rotation. Vortex stretching is amplified and shifts toward larger streamwise scales on the anti-cyclonic side, indicating the formation of elongated structures, while the spanwise scales remain nearly unchanged, reflecting anisotropic modulation. Enstrophy production is enhanced and exhibits spectral similarity with viscous dissipation on the anti-cyclonic side, reflecting active small-scale turbulence, while the cyclonic side shows weakened small-scale turbulent activity, consistent with re-laminarization. Spatial two-point correlations reveal large-scale, laminar-like structures with intermittent wall-normal fluctuations on the cyclonic side. Temporal autocorrelations reveal enhanced coherence on the anti-cyclonic side and slowly evolving streamwise structures on the cyclonic side. Quadrant analysis reveals a sustained bursting cycle on the anti-cyclonic side and suppressed turbulence on the cyclonic side. Enstrophy production exhibits intermittent bursts on the anti-cyclonic side, marking regions of strong vorticity amplification.
Singh et al. (Thu,) studied this question.