搅拌槽内非牛顿流体流动场的数值模拟  

Numerical simulation of non-Newtonian fluid flow in a stirred tank

作　　者：周国忠[1] 聂毅强[1] 包雨云[1] 施力田[1] 王英琛[1] 

机构地区：[1]北京化工大学化学工程学院,北京100029

出　　处：《北京化工大学学报（自然科学版）》2002年第4期4-7,共4页Journal of Beijing University of Chemical Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目 (2 9976 0 0 2);橡塑新材料合成国家工程研究中心基金资助项目

摘　　要：对搅拌槽内非牛顿流体湍流流动的数值研究还很缺乏。文中尝试利用k ε模型计算了假塑性流体羧甲基纤维素钠 (CMC)水溶液在搅拌槽内的三维流动场 ,并与粒子成像测速 (PIV)法测得的实验结果进行了比较。计算结果表明 ,非牛顿流体CMC水溶液的宏观流动场与牛顿流体 (水 )的流动场有较大差异 ,主要是主体流动减弱 ,并在叶端附近形成涡旋流动。主体流动区内的速度分布与PIV测量结果吻合较好。剪切速率在槽内的分布相差较大 ,桨叶附近与槽壁处的剪切速率较大 。Numerical simulation of non Newtonian turbulent flow in a stirred tank is still on an early age and further development is needed. In this paper, the flow field of a shear thinning fluid carboxymethylcellulose(CMC) was simulated using standard k ε model. The results predicted a distinct difference in velocity distribution between a shear thinning fluid and a simple Newtonian fluid(water). The main circulation loop was decreased and a swirl flow was formed at the tip of the impeller. The predicted non Newtonian fluid velocity agreed well with velocity measured by Particle Image Velocimetry(PIV). The simulated shear rate distribution is different in the whole tank and its value near the impeller and tank wall is high.

关 键 词：流动场 非牛顿流体 搅拌槽 湍流流动 数值模拟 流动力学模型 

分 类 号：TQ021.1[化学工程] TQ051.7