| Abstract
| - A computer simulation of a section of the interior regionof a liquid chromatographic column is performed. Thedetailed fluid flow profile is provided from a microscopiccalculation of low Reynolds number flow through arandom packed bed of nonporous spherical particles. Thefluid mechanical calculations are performed on a parallelprocessor computer utilizing the lattice Boltzmann technique. Convection, diffusion, and retention in this flowfield are calculated using a stochastic-based algorithm.This computational scheme provides for the ability toreproduce the essential dynamics of the chromatographicprocess from the fundamental considerations of particlegeometry, particle size, flow velocity, solute diffusioncoefficient, and solute retention parameters when retention is utilized. The simulation data are fit to semiempirical models. The best agreement is found for the “coupling” model of Giddings and the four-parameter Knoxmodel. These models are verified over a wide range ofparticle sizes and flow velocities at both low and highvelocity. The simulations appear to capture the essentialdynamics of the chromatographic flow process for nondimensional flow velocities (Péclet number) less than500. Since the same packing geometry is utilized fordifferent particle size studies, the interpretation of theparameter estimates from these models can be extendedto the physical column model. The simulations reportedhere agree very well with a number of experimentsreported previously.
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