Deposition of Brownian particles in porous media: Modified boundary conditions for the sphere-in-cell model

Modified boundary conditions for solving the convective diffusion equation for Brownian particles as applied in the Happel sphere-in-cell porous medium model are presented. With the modified boundary conditions, the convective diffusion equation correctly predicts the deposition rates of Brownian particles at low Peclet numbers. At moderate and large Peclet numbers, colloid deposition rates are similar to those calculated with existing models.