【摘要】 为考察粒子变形特性对粒子DLD运动轨迹的影响,该文结合柔性粒子弹簧模型和浸入边界-格子玻尔兹曼法(IB-LBM),对圆形粒子分离特性的影响进行了数值模拟研究。研究发现,粒子内外黏度比和粒子刚度等物理性状参数可以在一定程度上改变圆形粒子的临界尺寸以及运动模式,决定分离情况的主要因素依然是圆形粒子尺寸。通过考察粒子在分离运动过程中的长径变化和毛细数,研究发现对于圆形粒子,毛细数越小,粒子变形能力越差,粒子的有效尺寸越小,越容易走之字形运动模式。该结论可以加深对圆形粒子DLD分离机制的理解,同时为设计DLD分离装置提供了理论依据。更多还原

【Abstract】 In order to investigate how deformability effects on bead’s trajectory in deterministic lateral displacement(DLD) device, in this paper the beads’ separation process is simulated by combining particle spring model and immersed-boundarylattice-Boltzmann method. It is found that viscosity contrast and particle stiffness can change the beads’ critical sizes as well as traveling mode to some extent. Considering the importance of the bead’s critical size in DLD separation, the change of particle maximum length and capillary number are investigated. The results show that small capillary number leads to less deformability and smaller effective size. The bead with small capillary number tends to go into zigzag mode. This conclusion deepens our understanding towards bead’s DLD separation and provide strong theoretical basis for the design of separating device.更多还原