气升式环流反应器流动特性的数值模拟

应用Fluent计算流体力学软件，通过数值模拟的方法考察了气升式环流反应器内导流简直径、导流筒高度、导流筒安装高度以及液相进口速度对反应器内两相流动的影响。计算结果表明：导流简直径增大。液相循环量和上升段气含率均增大；导流筒高度增大，液相循环速度和循环量均增大，但是当导流筒的高径比增加到6．3后，液相循环速度和循环量反而减小；导流筒安装高度增加．液相循环速度及循环量均增大，升液管气含率降低；增加液相的进口速度，虽然上升段的液速有所增加，但是降液管循环液速及循环量基本不受影响。最后计算了反应器内液相速度随进口气速的变化情况，并与实际测量值进行了比较，模拟值和测氨值都表明随着进口气速的增加，液相循环速度随着进口气速的增加而增加．两者呈现良好的一致性。

Numerical Simulation of the Hydrodynamics of the Airlift Loop Reactor

The effects of draft-tuber diameter, height, installing height and the liquid inlet velocity were investigated with the Computational Fluid Dynamic (CFD) simulation. The simulation indicated that the gas-holdup in the riser and liquid circulation increased with the draft-tuber's diameter. Both the liquid velocity and the liquid circulation increased with the draft-tuber's height, but the increasing tendency will be reversed when the height-diameter ratio of draft-tuber reached 6.3. The liquid velocity and liquid circulation go up while the gas hold-up in the riser goes down with the draft-tuber's installing height. The increase of the inlet liquid velocity leads to the increase of superficial liquid velocity in the riser but it has tiny effect on the down-comer. The effect of inlet gas velocity on the liquid velocity was simulated. The result showed that the liquid velocity increased with the inlet gas velocity which corresponded with the experimental value very well.