CONTINUOUS MEASUREMENTS OF BUBBLE CHARACT ERISTICS IN A MOLTEN IRON BATH WITH AR GAS BUBBLING

A novel electro-resistivity probe was developed for measuring the bubb le characteristics in a molten iron bath subject to centric bottom Ar gas injection. This probe is able to be continuously used for about tw o hours at a bath temperature of 1250-degrees-C. The radial and vertic al distributions of gas holdup alpha, bubble frequency f(B), bubble ri sing velocity u(B)BAR. and bubble diameter d(B)BAR were measured for t he Ar gas flow rate of 50 and 100cm3/s (at 1250-degrees-C). The Ar gas preheated up to 1250-degrees-C was injected from the bottom nozzle at 1250-degrees-C. The results were compared with empirical correlations derived from cold and hot model experiments. The values of alpha, f(B ) and u(B)BAR measured in the vicinity of bath surface were approximat ed satisfactorily by correlations proposed by the present authors, but they did not agree with the experimental results of Kawakami et al. T he measured values of d(B)BAR were a little smaller than those of Sano et al. and Irons et al.