Abstract: On the basis of Naiver - Stokes equations and KKKKKKKKKKK - 33333333333 turbulence model, the transient hydrodynamics behavior of liquid jet loop reactor with periodically oscillating operation which is carried out by switching of central and circumambient jet was studied. The flow developing time Tv,1 (operation when injection shifted from circumambient to central inlet), Tv,2(operation when injection shifted from central to circumambient inlet) and the whole oscillating period Tv(the sum of fv,1 and Tv,2) were determined. The effects of liquid injection rate, the height of draft tube and the ratio between the diameters of reactor with draft lube on developing time, oscillating period were also investigated.

摘要： <正>液体喷射单相环流反应器在化学和生化工程中应用较多。有关其流动特性,Blanke已作了较为全面的综述。一般这种反应器的操作采取中心或环隙喷射的定态方式,Douglas和Baird等对反应器的研究认为,传统的定态操作并不能保证过程总处于最佳状态,在某些情况下进行非定态的振荡操作,可能更有利于反应和传递,其中确定合适的振荡周期是实现这一目的的关键。文献[5,6]利用内环流反应器中心气升和环隙气升的周期切换,实现了环流反应器的振荡操作,并较有效地提高了反应器溶氧传质系数。将这种操作方式用于面包酵母的培养,可增加细胞收率。环流反应器振荡操作时流体流动的特点不单表现为流动处于非定态,而且当喷射位置从中心切向环隙或相反时,流体流动方向都要反向变化一次。因此