Forces and torques on spheroidal particles in various types of viscous shear flow By PIERO OLLA
نویسنده
چکیده
The behavior of rigid spheroidal particles in a viscous flow is analysed using a vector spherical harmonics representation of the Stokes equation. This representation allows to clearly separate flow components associated with force, torque and stress. At the same time, it is possible to catalog forces and torques on particles in shear flows, in function of particle shape and shear characteristics, in a very simple way. Various applications have been discussed. The transverse displacement of a spheroidal particle due to the encounter with another particle in a linear shear has been calculated. The corresponding contribution to shear induced transverse diffusivity in suspensions has been obtained as well. The torque on a not fore-aft symmetric particle in a channel flow, has been calculated, and the relevance of this effect to the migration of particles to the middle of narrow ducts has been discussed.
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