底吹き円筒容器内水-空気系気泡噴流の浮力領域における気泡特性

抄録

The flow field in vertical bubbling jet in a cylindrical vessel with bottom blowing can be divided into four regions. They are named the momentum, transition, buoyancy and surface region from the nozzle exit. In a previous paper, bubble behavior characterized by gas holdup, bubble frequency, bubble rise velocity and so on was clarified for the momentum region in which inertia force of injected gas played an important role. In the present study, bubble behavior in the buoyancy region in which buoyancy force of bubbles governed the flow was investigated by means of two kinds of electro-resistivity probes, a high speed video camera, and a laser Doppler velocimeter. The bubble behavior was not affected by nozzle diameter and bath diameter. Therefore, correlations for gas holdup, bubble frequency and bubble rise velocity were proposed as functions of gas flow rate.