A Numerical Simulation of Unsteady Two-phase Gas-Liquid Flow in a Large-scale Air-lift Pump

摘要

It is anticipated that dynamical responses tochanges of air supply become more complicated in a largescaleair-lift pump. Then it is inevitable to grasp unsteady flowcharacteristics in air-lift pumps for safety operations of thesystems. Therefore the purposes of this study are to obtainsafety operational conditions for air-lift pumps of lifting marinemineral resources such as manganese nodules from deep-seafloor to a mining ship. The numerical method was applied to anair-lift pump of 5,000 m depth. In this paper, we discussespecially the unsteady flow characteristics of gas-liquid two-phase flow in beginning and increasing of air supply, inincreasing and reducing of back-pressure, and in stopping of air supply.