连续三相喷射环流反应器的实验和数值模拟  

Experimental and numerical simulation on sequential three phase jet-loop reactor

作　　者：高用祥 洪都 成有为[1] 王丽军[1] 李希[1] GAO Yong-xiang;HONG Du;CHENG You-wei;WANG Li-jun;LI Xi(College of Chemical and Biological Engineering,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]浙江大学化学工程与生物工程学院,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2019年第5期997-1005,共9页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(U1361112)

摘　　要：利用Pavlov管和电导探针分别测量含小颗粒(Stokes数小于1.0)的连续气液固三相喷射环流反应器内轴向液速和气体体积分数分布.提出大气泡-小气泡-浆态相三相流体力学模型,以模拟三相喷射环流反应器的流体力学行为,对大气泡相和小气泡相分别考虑尾涡加速和气泡阻碍效应并修正其曳力.对于上升区和下降区,流场模拟结果均与实验结果较吻合.利用模型预测不同固体体积分数下的气体体积分数与轴向液速分布,结果表明,在考虑的固体体积分数范围内,气体体积分数随固体体积分数增加而下降,液体循环速度随固体体积分数增加而略有上升,其原因主要是反应器内平均气泡直径随固体体积分数增加而增大,进而导致气泡浮升速度加大并增强周围流体的加速运动.Distribution of axial liquid velocity and gas volume fraction in a sequential gas-liquid-solid three phase jet-loop reactor containing small particles with Stokes number less than 1.0 were measured by Pavlov tube and conductivity probe, respectively. A large bubble-small bubble-slurry three phase fluid dynamic model, incorporating the respective consideration of wake acceleration and bubble hindrance effect for large and small bubble phases in the modified drag forces, was developed to simulate the hydrodynamics in a three phase jet-loop reactor. The numerical results of flow filed in the riser and downcomer were in good agreement with the experimental results. The model was used to predict the axial liquid velocity and gas volume fraction in different solid volume fractions. Results showed that the gas volume fraction decreased while the liquid circulation velocity increased slightly with the increase of solid volume fraction, under the considered solid volume fraction range. The reason is that the average bubble diameter increases when solid volume fraction rises, which increases the bubble rise velocity and enhances the accelerated movement of the surrounding fluid.

关 键 词：多相流 计算流体力学(CFD) 喷射环流反应器 气体体积分数 轴向液速 

分 类 号：TQ21[化学工程—有机化工]