Sedimentation velocity and potential in concentrated suspensions of charged porous spheres.

摘要: The body-force-driven migration in a homogeneous suspension of polyelectrolyte molecules or charged flocs an electrolyte solution is analyzed. model used for the particle porous sphere which density hydrodynamic frictional segments, and therefore also that fixed charges, constant. effects interactions are taken into account by employing unit cell model. overlap electric double layers adjacent particles allowed relaxation effect layer surrounding each considered. electrokinetic equations govern electrostatic potential profile, ionic concentration (or electrochemical energy) distributions, fluid velocity field inside outside linearized assuming system only slightly distorted from equilibrium. Using regular perturbation method, these solved symmetrically with charges as small parameter. An analytical expression settling obtained balance among its gravitational, electrostatic, forces. A closed-form formula sedimentation identical spheres derived using requirement zero net current. dependence on volume fraction other properties particle-solution found to be quite complicated.