Abstract
Abstract
In the present work, the critical aspects of how particles influence the structure of secondary flows are explored. Despite its significance in the manipulation and detection of particles and cells in microfluidic applications, this topic has received limited attention until now. Employing a fluid-structure interaction method, this research examines the two-way coupling between particles and secondary flows at a Reynolds number (Re) of 80, revealing significant insights into the behaviour of particles under such conditions. The investigation explores the intricate relationships between particle transverse migration, rotation, and secondary flow fields, emphasizing how these interactions amplify with both particle size and secondary flow intensity. The findings underscore the critical role of secondary flow vortices in generating drag forces, which in turn influence particle motion. Notably, the study demonstrates that for larger particles (a/H=0.375), the vortex-induced additional force acts repulsively, discouraging their movement along with the secondary flow. Through detailed analysis, this paper elucidates the lateral migration behaviour of particles, their rotational dynamics in response to secondary flows, and the overarching effects of their interactions with secondary flow structures. This research provides insights into the fundamental mechanisms governing particle behaviour in microfluidic environments, offering potential advancements in particle manipulation and detection.