Infiltration and resuspension of dilute particle suspensions in micro cavity flow
Infiltration and resuspension of dilute particle suspensions in micro cavity flow
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DOI：
10.1016/j.powtec.2021.09.066
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发表时间：
2022-01
影响因子：
5.2
通讯作者：
Wenwei Liu;Chaomei Zheng;Chuan-Yu Wu
中科院分区：
文献类型：
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作者：
Wenwei Liu;Chaomei Zheng;Chuan-Yu Wu
本文用格子Boltzmann方法和离散元方法相结合的方法，数值分析了颗粒悬浮物在进入空腔的槽道流中的沉降。本文的工作主要集中在封闭腔中颗粒的捕获和捕获后的颗粒动力学。对颗粒运动的仔细研究揭示了三种不同的动力学行为：i）再悬浮，ii）中心涡的循环和iii）空腔后缘的沉积。系统地研究了流体惯性、颗粒密度和空腔尺寸对入渗和再悬浮行为的影响。结果表明，减小雷诺数、增加空腔长度和深度均能提高捕集效率。然后通过推导经验无量纲捕集数Tp确定了三种不同的捕集效率区域：当Tp < 1时为再悬浮区域，当1 ≤Tp≤ 2.5时为连续循环区域，当Tp> 2.5时为完全捕集区域。
Sedimentation of particle suspensions in a channel flow into a cavity is analysed numerically using a lattice Boltzmann method coupled with a discrete element method. The work focuses on the entrapment of particles inside a confined cavity and the particle dynamics after entrapment. A close examination of the particle motions reveals three distinct dynamic behaviours: i) resuspension, ii) circulation in the central vortex and iii) deposition to the rear edge of the cavity. The effects of fluid inertia, particle density and cavity size on the infiltration and resuspension behaviours are systematically investigated. The results show that decreasing the Reynolds number, and increasing the length and depth of the cavity all lead to an increase in the trap efficiency. Three distinctive regimes with respect to the trap efficiency were then identified by deriving an empirical dimensionless trap numberTp: a resuspension regime whenTp< 1, a continuous circulating regime when 1 ≤Tp≤ 2.5, and a fully trapped regime whenTp> 2.5.