CFD Simulation of Gas-Liquid Flow in an Internal Loop Airlift Reactor with Different Draft Tubes
气升式内循环反应器的数值模拟和结构参数

An internal loop airlift reactor(ILAR)(1240 mm height,165 mm diameter) with draft tube(590 m in height) has been simulated using computational fluid dynamics with Euler-Euler model.The effects of draft tube(diameter and bottom gap height) on gas holdup and water velocity are studied.The results show that superficial gas velocity,draft tube diameter and bottom gap height of draft tube have a great effect on gas holdup and water superficial velocity,especially in the downcomer of ILAR.With increasing of superficial gas velocity,the gas holdup in ILAR is increased.When the internal diameter ratio of draft tube to reactor,Dt/D,is 058,the gas-liquid circulation is the easiest to come outBut the gas holdup and gas-liquid velocity are low,when the bottom height of draft tube is 30 mm.Moreover,with the tongue angle of gas-liquid separator is increased,the gas holdup in the downcomer is increased.However,when the tongue angle is 45o,the gas-liquid velocity is the largest.