Hybrid Simulations of Two-Way Coupled Turbulent Magnetohydrodynamic Flows

摘要

We have applied a hybrid approach that combines the transient Reynolds-averaged Navier-Stokes (T-RANS) method for velocity and hydrodynamical turbulence with a direct numerical solving (DNS) of the magnetic induction equation for two-way coupled turbulent magnetohydrodynamic (MHD) flows. An originally developed electromagnetically extended two-equations (k-ε) eddy-viscosity-based model was used for the hydrodynamical turbulence closure. The validation of the hybrid approach was performed by simulating the Riga-dynamo experimental setup, which is characterized by an intermediate value of the magnetic Reynolds number (Re_m ≈ 20) and a very high value of the hydrodynamical Reynolds number (Re ≈ 3.5 × 10~6). Numerical simulations provided all general features of the magnetic saturation regime with the frequency and amplitude of the generated magnetic field in good agreement with available experiments.