Effect of Temperature and Multichannel Stopper Rod on Bubbles in Water Model of a Steel Continuous Caster

Abstract

Herein, effects of the water temperature and a multichannel stopper rod with various gas hole diameters on the size and distribution of bubbles are investigated using a 0.5‐scale water model of a steel slab continuous casting mold. The breakage ratio of bubbles increases with the increasing of the water temperature. The mean diameter of bubbles decreases from 2.11 to 1.32 mm with the water temperature increasing from 25 to 34 °C. The smaller dynamic viscosity and surface tension of the water at a higher temperature result in large turbulence velocity fluctuation at the bottom of the submerged entry nozzle. The effect of water temperature on the bubble size and distribution can hardly be ignored in the water model experiment. With the increase of the hole diameter of the gas channel (Dh) of the stopper rod, the number of bubbles first decreases to the minimum value atDh = 1.5 mm and then increases, and bubble mean diameters increase, and the horizontal dispersion and penetration depth increase when the bubble diameter is larger than 1 mm. The multichannel stopper rod with the gas hole diameter of 1.5 mm is recommended under the current specific continuous casting condition.