Study of electromagnetically driven flows of electrolytes in a cylindrical vessel: Effect of electrical conductivity, magnetic field, and electric current

Abstract

The paper reports on the flow in a cylindrical vessel filled with an electrolyte and driven by a Lorentz force generated by the interaction of a dc current and the magnetic field of a permanent magnet. Using a two-dimensional (2D) particle image velocimetry (PIV) system, we analyze the velocity field in an axial-oriented central plane. In particular, two different electrolytes are used as working fluids: Potassium chloride and Sodium bicarbonate. For each electrolyte, three different values for electric current are explored: 3, 4, and 5 mA; as well as, two different magnets are used. The first magnet partially covers the diameter of the cavity; whereas the second one is larger and three times more intense. Velocity fields obtained for electrolytes and magnets are compared. We found that, the highest the conductivity of the electrolyte, the highest a parameter related to the kinetic energy of the velocity field in the plane. For the square magnet, this parameter increases nearly linear as a function of the current; in contrast, for the rectangular magnet, it slightly decreases. Additionally, 3D numerical simulations are performed using the COMSOL Multiphysics software. The electric scalar potential magnetohydrodynamic (MHD) formulation is implemented to model the flow behavior. The computed numerical results reproduce the main characteristics of the flow.