Abstract:
The present work concerns the orientation dynamics of anisotropic particles in
viscoelastic °uids. A spheroidal geometry is taken as being representative of an
anisotropic, axisymmetric particle, and the work is an analytical investigation of
the e®ects of weak inertia and viscoelasticity on the orientation of a spheroidal
particle (both prolate and oblate) of an arbitrary aspect ratio in two canonical °ow
situations:
1. A spheroid sedimenting in a quiescent °uid, and
2. A neutrally buoyant spheroid in a simple shear °ow
Applications include sedimentation of muds and slurries, processing of cellulose
¯ber suspensions in the paper and pulp industry, and processing of ¯lled poly-
meric materials (wherein anisotropic clay particles are typically used as cheap ¯ller
materials).
