Abstract: 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 0.58, the gas-liquid circulation is the easiest to come out. But 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.

Key words: internal loop airlift reactor, Euler-Euler model, gas holdup, water velocity

摘要： 采用Euler-Euler双流体模型对内循环反应器(高1240 mm，直径165 mm，导流筒高590 mm)进行数值模拟，考察了表观气速、导流筒结构(导流筒内径比Dt/D，底隙高度)对反应器内上升区、下降区流体力学参数(气含率、液体速度)的影响. 结果显示，表观气速、导流筒内径、底隙高度对反应器气含率、液体速度有很大影响，随表观气速增加，反应器上升区、下降区气含率都增加，导流筒内径比为0.58时更易实现气液循环，底隙高度为30 mm时反应器内下降区气含率、气液速度都最小；气液分离器角度越大，进入下降区的气体越多，当气液分离器角度为45o时，能更好地实现气液循环.

关键词: 内循环反应器, Euler-Euler双流体模型, 气含率, 液速