Oscillations of free surface of rotating liquid metal in a cylindrical cell

V. Eltishchev - G. Losev - I. Kolesnichenko

Institute of Continuous Media Mechanics, RAS Ural Branch, Perm, Russia

Abstract
This work is concerned with the study of oscillations of the free top surface of liquid metal using an induction level sensor. Liquid metal is contained in a cylindrical cell with electrically conducting walls. A constant electric current of fixed value is passed through the metal from a small area at the bottom of the cell to the side wall, which generates an electrovortex flow. The action of an external uniform axial magnetic field initiates rotation of liquid metal and development of a complex poloidal unsteady flow. It affects the oscillations of the free boundary which were studied using an inductive level sensor. The reliability of the sensor measurements is confirmed by comparison with the data obtained by ultrasonic Doppler velocimeter probes. It turned out that the oscillations occur with two frequencies. Their values increase with the growth of the external magnetic field. Oscillations with a higher frequency were initiated by the azimuthal flow of liquid metal and oscillations with a lower frequency were generated by the poloidal flow. Figs 6, Refs 19.