Magnetic field in decaying grid turbulence of liquid sodium

V. Noskov¹ - R. Stepanov¹ - P. Frick^{1, 2} - A. Pavlinov¹ - S. Denisov¹

¹ Institute of Continuous Media Mechanics, 1 Acad. Korolyov str., Perm 614013, Russia
² Perm State University, 15 Bukireva str., Perm, Russia

Abstract
For the first time grid-induced turbulence in a spin-down flow of liquid sodium is studied. Grids provide injection of kinetic energy directly into small scales. It is shown that the flow dynamics change dramatically in comparison with the flow in a free channel, where turbulence develops due to the interaction of a large-scale flow with the wall. The evolution of both velocity and magnetic field fluctuations is investigated, showing that the induction effects have a sufficient time to generate a small-scale magnetic field. The contribution of turbulent magnetic diffusivity is estimated to be about 3%. Figs 11, Refs 20.