Abstract
Effects of electrolytic bubbles on the IR drop of caustic soda solution in a vertical cell of one meter height were studied under both free and forced convection. Three pairs of Luggin‐Haber probes were positioned near the anode and the cathode to determine the solution IR drop during electrolysis. A sectioned electrode having 10 segments was employed to obtain the current distribution from the bottom to the top of cell. The superficial resistivity of the solution containing gas bubbles agreed well with the Bruggemann equation. The solution IR drop decreased significantly when adequate conditions or cell geometry for solution circulation were provided. The anode‐to‐cathode gap was found to be the most important parameter for reduction of the solution IR drop in a vertical cell.