On the spin-down of rotating MHD flow in an annular gap

B. Mikhailovich¹ - A. Shapiro² - R. Stepanov^{3, 4}

¹ Department of Mechanical Engineering, Ben-Gurion University of the Negev, P.O.B. 653, Beer-Sheva 8410501, Israel
² Physics Department, Shamoon College of Engineering, Bialik St., Beer-Sheva 84100, Israel
³ Institute of Continuous Media Mechanics, 1 Korolyov str., Perm 614013, Russia
⁴ State National Research Polytechnical University of Perm, 29 Komsomolskii ave., Perm 614990, Russia

Abstract
The behavior of azimuthal and radial velocity components of transient and free decaying rotating MHD flow in an annular gap of rectangular cross-section in an axial magnetic field has been studied. Experimental values of the velocity components of the flow were measured using a conductive anemometric system. Analysis of mean and oscillating characteristics was carried out using a continuous wavelet transformation based on the Morlet function. Signal scalograms were plotted and analyzed. It is shown that the dominating azimuthal mode m=1 of the velocity field develops over the whole volume in a transient regime and then decays exponentially with mean flow. Figs 6, Refs 25.