THESIS
2015
xvii, 133 pages : illustrations ; 30 cm
Abstract
The hydrodynamic reciprocal theorem for Stokes flow is generalized to incorporate
the Navier slip boundary condition, which can be derived from Onsager's
variational principle of least energy dissipation. The hydrodynamic reciprocal
relations and the Jeffery orbit, both of which arise from the motion of a slippery
anisotropic particle in a simple viscous shear
flow, are investigated theoretically
and numerically using the fluid particle dynamics method [Phys. Rev. Lett.
85, 1338(2000)]. In numerical simulations, the Navier slip boundary condition
is realized via introducing a thin layer of fluid with low viscosity at interfacial
region. For a slippery elliptical particle in a linear shear flow, the hydrodynamic
reciprocal relations between the rotational torque and the shea...[
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The hydrodynamic reciprocal theorem for Stokes flow is generalized to incorporate
the Navier slip boundary condition, which can be derived from Onsager's
variational principle of least energy dissipation. The hydrodynamic reciprocal
relations and the Jeffery orbit, both of which arise from the motion of a slippery
anisotropic particle in a simple viscous shear
flow, are investigated theoretically
and numerically using the fluid particle dynamics method [Phys. Rev. Lett.
85, 1338(2000)]. In numerical simulations, the Navier slip boundary condition
is realized via introducing a thin layer of fluid with low viscosity at interfacial
region. For a slippery elliptical particle in a linear shear flow, the hydrodynamic
reciprocal relations between the rotational torque and the shear stress are studied
and related to the Jeffery orbit, showing that the boundary slip can effectively
enhance the anisotropy of the particle. Physically, by replacing the no-slip
boundary condition with the Navier slip condition at the particle surface, the
cross coupling between the rotational torque and the shear stress is enhanced,
as manifested through a dimensionless parameter in both the hydrodynamic reciprocal
relations and the Jeffery orbit. The connection of the present work to
nematic liquid crystals' constitutive relations is discussed. In addition, simulations
for a circular particle patterned with portions of no-slip and Navier slip are
carried out, showing that the particle possesses an effective anisotropy and follows
the Jeffery orbit as well. This effective anisotropy can be tuned by changing
the ratio of no-slip portion to slip portion.
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