抄録
It is anticipated that the dynamical responses to changes of air supply and solid supply become more complicated in an air-lift pump for lifting deep-sea mineral resources. Then it is inevitable to grasp unsteady flow characteristics in air-lift pumps for safety operations of the systems. Therefore, the purpose of this study is to obtain safety operational conditions for air-lift pumps of lifting marine mineral resources such as manganese nodules from deep-sea floor to a mining ship. The numerical method was applied to an air-lift pump of 5, 000 m depth. In this paper, we discuss the unsteady flow characteristics of gas-liquid-solid three-phase flow in beginning and stopping of solid supply, in increasing and reducing of back-pressure, in fluctuating of solid supply, and reducing and returning of air supply from the viewpoint of practical techniques.