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Contribution to the study of the dislodgment conditions of spheroids from a surface in fluid flow
Summary
Researchers used theoretical fluid mechanics to derive the critical conditions under which prolate and oblate spheroidal particles resting on a surface are dislodged by fluid flow. They found that a rolling mode always occurs first, and that asperity geometry acts as a pivot point governing critical dislodgment conditions, with relevance to understanding how microplastic particles are mobilized in flowing water.
In this Letter, the concept of an asperity acting as a pivot point is used to investigate the critical conditions under which a spheroid resting on a surface is dislodged by fluid flow. The critical conditions are derived for prolate spheroids with the axis of revolution aligned with the flow direction and deduced for a sphere and oblate spheroids with the axis of revolution perpendicular to the surface. It is also found that the rolling mode always occurs first in the considered configuration.
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