Bubble Behavior in Hg-Air Vertical Bubbling Jets in a Cylindrical Vessel

Abstract

A vertical bubbling jet was generated in a cylindrical mercury bath by injecting air from the bottom through a centric nozzle. Gas holdup α and bubble frequency f_B in the mercury-air vertical bubbling jet were measured by means of an electro-resistivity probe. On the basis of the present and other previously published experimental results, correlations for α, f_B and mean bubble rising velocity [u.gif]_B were derived for bubbling jets with a density ratio ρ_l/ρ_g between 780 and 11 000 as functions of Q_g, d_n, σ and ρ_l/ρ_g, where Q_g is the injected gas flow rate, d_n is the inner diameter of Nozzle, σ is the surface tension of liquid, ρ_l is the density of liquid and ρ_g is the density of gas. These correlations were found to be valid in the vicinity of the nozzle exit where the expansion of gas due to static pressure change was negligible.