离心萃取器混合区内三相流的CFD-PBM模拟  

CFD-PBM simulation of three-phase flow in the mixing zone of a centrifugal contactor

作　　者：段五华[1] 王澄谦 郑强 DUAN Wuhua;WANG Chengqian;ZHENG Qiang(Institute of Nuclear and New Energy Technology,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学核能与新能源技术研究院,北京100084

出　　处：《流体机械》2021年第11期25-32,共8页Fluid Machinery

基　　金：国家自然科学基金资助项目(21978149)。

摘　　要：为获得环隙式离心萃取器运行时混合区内真实气-液-液三相流流动特性,采用欧拉-欧拉多相流模型和群体平衡模型(PBM),并分别采用模拟软件ANSYS自带的MUSIG和直接正交矩量法(DQMOM)求解群体平衡模型,对Ф70 mm环隙式离心萃取器混合区内气-液-液三相流进行了CFD-PBM模拟研究,以获得气-液-液三相流的相分布和液滴平均直径(d_(32))分布。结果表明,混合区内有机相在两相混合液中分布比较均匀,但在局部地区形成了富有机相区和富水相区;流体的湍流动能和湍动耗散率在自由液面处和转筒外壁处较大,而在混合区旋涡中心处则较小;当两进口水相平均流速均为0.02 m/s,进口有机相体积分数为0.01,转速为1 800~3 600 r/min时,通过MUSIG模拟获得的混合区中气-液-液三相流中有机相的d_(32)为110~150 μm,而通过DQMOM模拟获得的混合区中气-液-液三相流中有机相的d_(32)为50~130 μm,并与试验测得的结果基本一致,且d_(32)随着转速的增大和进口有机相体积分数的减小而减小。In order to obtain the true gas-liquid-liquid three-phase flow characteristics in the mixing zone of the ACC during its operation,the computational fluid dynamic(CFD)-population balance model(PBM) simulation of the gas-liquid-liquid three-phase flow in the mixing zone of a Ф70 mm ACC was carried out to obtain the phase and Sauter mean diameter(d_(32))distributions in the gas-liquid-liquid three-phase flow using the Eulerian-Eulerian multi-phase flow model and PBM.PBM was solved using MUSIG in the simulation software ANSYS and direct quadrature method of moments(DQMOM),respectively.The results show that the organic phase in the mixing zone is uniformly distributed in the mixture of two liquid phases,but there are aqueous-rich regions and organic-rich regions in local areas.Both the turbulent kinetic energy and turbulent dissipation rate of the fluids on the free liquid surface and outer wall of the rotor are larger than those in the vortex center.When mean flow velocities of the two inlet aqueous phases are 0.02 m/s,volume fraction of the inlet organic phase is 0.01,and rotational speed is in the range of 1 800~3 600 r/min,d_(32)of the organic phase in the gas-liquid-liquid three-phase flow of the mixing zone is in the range of 110~150 μm obtained by MUSIG simulation,while d_(32)of the organic phase in the gas-liquid-liquid three-phase flow of the mixing zone is in the range of 50~130 μm obtained by DQMOM simulation,which is basically in agreement with the experimental results.Meanwhile,d_(32)decreases with the increase of the rotational speed and decrease of volume fraction of the inlet organic phase.

关 键 词：环隙式离心萃取器 计算流体力学(CFD) 群体平衡模型(PBM) 气-液-液三相流 

分 类 号：TH138.8[机械工程—机械制造及自动化]