DOI: 10.1615/TSFP6
DYNAMO EFFECT IN MHD TURBULENT CHANNEL FLOW
RESUMO
The generation of large-scale magnetic field due to small-scale motion of a conducting fluid, which is called the dynamo action, is important in understanding magnetic fields in astro/geophysical objects and in controlled fusion devices. A large eddy simulation (LES) of magnetohydrodynamic (MHD) turbulent channel flow is carried out and turbulent statistics are obtained to investigate the dynamo effect. It is shown that a streamwise mean magnetic field is generated due to the effect of the turbulent electromotive force. It is suggested that the cross-helicity dynamo effect contributes to the turbulent electromotive force; that is, the electromotive force parallel to the mean vorticity is generated due to the turbulent cross helicity. The dynamo effect is also investigated using the transport equations for the turbulent kinetic and magnetic energies.