Effect of liquid depth on circulation in bubble columns: a visual study

Abstract

A literature review on bubble column circulation is presented. Experimental results for two 2-D bubble columns of different aspect ratios are presented confirming that at low liquid depths the 'Gulf-stream' or 'cooling-tower' pattern is observed. When the liquid depth exceeds the column width, while 'the multiple circulation cell' model was not realised, two staggered rows of vortices which resemble the Karman vortex street was observed. The present work is a visual study of the circulation pattern in comparison with the generally accepted flow patterns.