Particle migration in oscillatory torsional flows of concentrated suspensions
Particle migration in oscillatory torsional flows of concentrated suspensions
复制标题
浓悬浮液振荡扭转流中的颗粒迁移
DOI：
10.1122/1.3361668
复制
发表时间：
2010
影响因子：
3.3
通讯作者：
N. Shapley
中科院分区：
文献类型：
--
作者：
Kapil Deshpande;N. Shapley
本文对非胶体球浓悬浮液在平行平板间振荡扭转流中的颗粒迁移行为进行了实验研究。视频成像的径向漂移速度的染色示踪剂颗粒在单分散，0.4散装颗粒体积分数悬浮液在流动演变过程中进行。结合同步流变测量，颗粒跟踪提供了深入了解迁移现象。对于所有的情况下研究，示踪剂颗粒的平均位移每周期是径向向外的，是近似的振荡应变振幅的线性函数，同时也随着振荡的频率在一个接近平方反比的关系。测得的径向迁移速度超过了估计从悬浮平衡连续模型为相应的稳定流，可能是由于增加的微观结构的流动性在振荡流。一般来说，该公司...
This study presents an experimental investigation into particle migration behavior of concentrated suspensions of noncolloidal spheres in oscillatory torsional flows between parallel plates. Video imaging of the radial drift velocity of dyed tracer particles in a monodisperse, 0.4 bulk particle volume fraction suspension was performed during flow evolution. In conjunction with simultaneous rheological measurements, particle tracking provided insight into migration phenomena. For all of the cases studied, the average displacement of the tracer particles per cycle was directed radially outward and was approximately a linear function of the oscillatory strain amplitude while also varying with the frequency of oscillation in a nearly inverse square relationship. The measured radial migration velocity exceeded that estimated from the suspension balance continuum model for a corresponding steady flow, likely due to the increased microstructural mobility developed during oscillatory flow. Generally, the oscillat...