Flow-Induced Resuspension of Rigid-Link Fibers from Surfaces

Flow-induced removal of curly fibers from surfaces is studied. A generic rigid-link fiber model consisting of a chain of five ellipsoids with different orientations is developed, and used to study fiber resuspension in laminar and turbulent flows. The contact surfaces of the fiber with the wall are modeled as spherical joints. The hydrodynamic forces and torques acting on the ellipsoidal segments as well as the adhesion forces of nodes in contact with the surface are evaluated. Various possible modes of fiber detachment from the surface are identified, and the state of limiting equilibrium are analyzed. The critical velocities for detaching fibers of various sizes, orientations, and filament thicknesses are evaluated and discussed.