Dynamics of a spherical particle and the suspending low-Reynolds-number fluid confined by a cubic cav- ity were studied numerically. We calculated the particle's hydrodynamic mobilities along x -, y -, and z- directions at various locations in the cavity. The mobility is largest in the cavity center and decays as the particle becomes closer to no-slip walls. It was found that mobilities in the entire cubic cavity can be determined by a minimal set in a unit tetrahedron therein. Fluid vortices in the cavity induced by the particle motion were observed and analyzed. We also found that the particle can exhibit a drift motion perpendicular to the external force. Magnitude of the drift velocity normalized by the velocity along the direction of the external force depends on particle location and particle-to-cavity sizes ratio. This work forms the basis to understand more complex dynamics in microfluidic applications such as intracellular transport and encapsulation technologies.

Gaofeng Chen;Xikai Jiang

State Key Laboratory of Nonlinear Mechanics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China;School of Engineering Science,University of Chinese Academy of Sciences,Beijing 100049,China

力学快报（英文）

[1]Gaofeng Chen;Xikai Jiang-.Motion of a sphere and the suspending low-Reynolds-number fluid confined in a cubic cavity)[J].力学快报（英文）,2022(04):251-256

suspending

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