DETACHMENT OF RIGID-LINK FIBERS WITH LINKAGE CONTACT IN A TURBULENT BOUNDARY-LAYER FLOW

Fiber removal with linkage contact in a turbulent boundary layer flow is studied. A rigid-link fiber model which is composed of two ellipsoi ds and one cylindrical link is considered. It is assumed that the fibe r is in contact with the wall by the cylindrical linkage and a spheric al end joint. The onset of rolling and sliding detachments is analyzed to determine the condition for removal of fibers from the surface. Th e hydrodynamic forces and torques acting on the fiber attached to a wa ll, along with the adhesion forces of contact node and linkage, are us ed in the model development. For different adhesion models, the minimu m critical shear velocities for removing fibers of different sizes, or ientations, and thicknesses are evaluated and discussed.