具有溢流帽结构的旋流器流场特征及分离性能研究

针对普通旋流器运行过程中存在短路流导致溢流跑粗的问题,提出一种溢流帽式旋流器,并对其进行了数值模拟和试验研究。模拟结果表明,相比于普通旋流器,溢流帽式旋流器内空气柱直径减小,能耗降低,离心力场强度更大,流体切向速度增大,轴向速度降低,颗粒参与分离时间长,分离更充分,有利于改善溢流跑粗,提高分离效率。试验结果显示,溢流帽式旋流器-20μm颗粒分级质效率从36.97%增加到42.17%,分级量效率从39.68%增加到45.90%。并且随着溢流帽直径的增大,底流固相产率增大,溢流中粗颗粒含量减少,有效抑制了溢流跑粗现象。

Study on flow field characteristics and separation performance of hydrocyclone with overflow cap structure

In view of the problem of escape of coarse particles in the overflow due to the short-circuit flow,an overflow cap type hydrocyclone was proposed and numerical simulation and experimental research were carried out.The simulation results show that compared with traditional hydrocyclones,the diameter of the air-core in the overflow cap hydrocyclone decreased,the energy consumption was reduced,strength of the centrifugal force was greater,the tangential velocity of the fluid increased,the axial velocity decreased,the particles had long separation time in the hydrocyclone,and the separation was more complete,which is conducive to reducing escape of coarse particles in the overflow and improving separation efficiency.The experimental results show that,by using the overflow cap type hydrocyclone,the qualitative classification efficiency of-20 μm particles increased from 36.97% to 42.17%,and the quantitative classification efficiency of-20 μm particles increased from 39.68% to 45.90%.In addition,with the increase of diameter of the overflow cap,the underflow productive rate increased,the content of coarse particles in the overflow decreased,which verified that the escape of coarse particles mixed in the overflow was effectively restrained.