Abstract
A new type of machine that uses a two-phase jet flow has been developed. This machine is known as an aerator, and operates not only an aerating function using the normal two-phase jet flow, but also employs a simple method to carry out an anaerobic operation as well. The economic efficiency of such machines is a key issue, and this along with a high effectiveness is a desirable quality of any aeration machine. To respond to this challenge, it is necessary to gain hydrodynamic understanding of the flow phenomena in the tank, and this knowledge should be applied to an effective simulation method. Even now however, a complete understanding of gas-liquid dynamics in the tank has yet to be gained. Therefore, this study focuses on the flow properties inside the tank induced by the two-phase jet flow during the aeration process. As an underlying process of the flow phenomena whereby the two-phase jet flow falls to the free surface and produces a circulating flow in the tank, we chose to examine the phenomena just after a droplet falls into the gas-liquid interface. This was done in practice by observations using high speed video, experimental modeling, and also by numerical analysis. Subsequently, we could gain insights into the influence of a free-drop onto the gas-liquid surface. This basic data can clarify the mechanism of the flow in the tank, which is induced by the two-phase jet flow, and is detailed in this study.