Direct numerical simulation of the turbulent MHD channel flow at low magnetic Reynolds number for electric correlation characteristics

Abstract

Direct numerical simulation (DNS) of incompressible magnetohydrodynamic (MHD) turbulent channel flow has been performed under the low magnetic Reynolds number assumption. The velocity-electric field and electric-electric field correlations were studied in the present work for different magnetic field orientations. The Kenjeres-Hanjalic (K-H) model was validated with the DNS data in a term by term manner. The numerical results showed that the K-H model makes good predictions for most components of the velocity-electric field correlations. The mechanisms of turbulence suppression were also analyzed for different magnetic field orientations utilizing the DNS data and the K-H model. The results revealed that the dissipative MHD source term is responsible for the turbulence suppression for the case of streamwise and spanwise magnetic orientation, while the Lorentz force which speeds up the near-wall fluid and decreases the production term is responsible for the turbulence suppression for the case of the wall normal magnetic orientation.