LARGE-SCALE MEASUREMENTS OF THE PHYSICAL CHARACTERISTICS OF ROUND VERTICAL BUBBLE PLUMES IN LIQUIDS

The hydrodynamics of air/water plumes in a large-scale model of a meta llurgical ladle were investigated. The dimensions of the cylindrical v essel were 1600-mm ID and 2250-mm total height. The air was injected t hrough a centered nozzle. Axial and radial profiles of gas concentrati on, bubble frequency, and liquid and gas velocities were measured usin g electrical resistivity probes and a propeller flowmeter. It was foun d that the bubble plume is not at a fixed position but wanders away fr om the vertical vessel axis. This causes difficulties in the measureme nts, and special methods have to be designed to define and deduce repr oducible values for the characteristic plume quantities. In the analys is of the data, the various physical characteristics were related to z 0, the distance from the nozzle where the axial gas concentration is 5 0 pct. The maximum values of the radial profiles are presented in nond imensional correlations.