Shear induced aggregation in liquid suspensions

• Main Authors: Deng,Jiun-Ping, 鄧君屏
• Other Authors: Shiau,Lie-Ding
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/77288998096356858609

碩士 === 長庚大學 === 化工與材料工程研究所 === 93 === The aggregation of an initially well-dispersed suspension of particulates due to shear-induced collision is examined in laminar flow and in turbulent flow. Experiments in laminar flow are conducted by a cone-and-plate device on latex particles suspended in aqueous glycerol while experiments in turbulent flow are conducted by stirred tank. The corresponding shear rate in laminar flow and in turbulent flow is calculated as a function of the stirring rate. The rate of aggregation growth is measured as a function of time for different constant shear rate and suspension compositions. The experimental results show that the aggregate size increases rapidly in the early stage and then gradually reaches an equilibrium value due to the influence of hydrodynamic shear forces. An aggregation model is developed in this work to recover the collision efficiency and the equilibrium aggregate size from the experiment data.