Convection in a vertical layer of stratified magnetic fluid

A. A. Bozhko¹ - G. F. Putin¹ - A. S. Sidorov¹ - S. A. Suslov²

¹ Department of General Physics, Perm State National Research University, Perm, Russia
² Department of Mathematics, Swinburne University of Technology, Hawthorn, Victoria, Australia

Abstract
Infrared camera visualisation of convective flows in differentially heated vertical layers with the height-to-thickness ratios of 30 and 62.5 was used to demonstrate the influence of concentration stratification caused by gravitational sedimentation of magnetic particles and aggregates on the structure of convective motion. It is found that when a density gradient is established in an isothermal layer over a period of several weeks prior to the experiment, cellular structures occur after the heating begins. They persist for a significant time even after the magnetic field is applied and vertical thermomagnetic convection rolls appear eventually mixing the fluid. Figs 6, Refs 30.